101
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Barchenger DW, Lamour KH, Bosland PW. Challenges and Strategies for Breeding Resistance in Capsicum annuum to the Multifarious Pathogen, Phytophthora capsici. FRONTIERS IN PLANT SCIENCE 2018; 9:628. [PMID: 29868083 PMCID: PMC5962783 DOI: 10.3389/fpls.2018.00628] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2017] [Accepted: 04/20/2018] [Indexed: 05/20/2023]
Abstract
Phytophthora capsici is the most devastating pathogen for chile pepper production worldwide and current management strategies are not effective. The population structure of the pathogen is highly variable and few sources of widely applicable host resistance have been identified. Recent genomic advancements in the host and the pathogen provide important insights into the difficulties reported by epidemiological and physiological studies published over the past century. This review highlights important challenges unique to this complex pathosystem and suggests strategies for resistance breeding to help limit losses associated with P. capsici.
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Affiliation(s)
- Derek W. Barchenger
- Department of Plant and Environmental Sciences, New Mexico State University, Las Cruces, NM, United States
| | - Kurt H. Lamour
- Department of Entomology and Plant Pathology, The University of Tennessee, Knoxville, Knoxville, TN, United States
| | - Paul W. Bosland
- Department of Plant and Environmental Sciences, New Mexico State University, Las Cruces, NM, United States
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102
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Ma D, Zhu J, He L, Cui K, Mu W, Liu F. Baseline Sensitivity and Control Efficacy of Tetramycin Against Phytophthora capsici Isolates in China. PLANT DISEASE 2018; 102:863-868. [PMID: 30673383 DOI: 10.1094/pdis-09-17-1396-re] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Tetramycin is a new biopesticide that combines high-level and broad-spectrum fungicidal activity, low toxicity, and environmental safety. In this study, 90 Phytophthora capsici isolates obtained from various regions in southern China were characterized for their baseline sensitivity to tetramycin. The protective and curative activities of tetramycin against P. capsici were determined on leaves of pepper, and the control efficacy of tetramycin in greenhouse experiments was also determined. Compared with mycelial growth, the formation of sporangia and the discharge of zoospores were inhibited by lower concentrations of tetramycin, approximately 5 µg ml-1 on V8 media. The frequency distribution curves for the tetramycin sensitivity were unimodal, with mean values for the fungicide concentration that reduced mycelial growth, sporangia formation, and zoospore discharge by 50% compared with the control of 1.18 ± 0.91, 0.64 ± 0.42, and 0.63 ± 0.30 µg ml-1, respectively. In addition, no correlation was observed between tetramycin and other fungicides tested, including mandipropamid, azoxystrobin, mefenoxam, fluazinam, fluopicolide, and famoxadone. Tetramycin exhibited both protective and curative effects against P. capsici in vitro, and its protective activity was better than its curative activity. In greenhouse experiments, tetramycin concentration of 60 and 90 µg ml-1 provided a protective control efficacy of 47.1 to 56.4% and curative efficacy of 43.3 to 52.7%. These results demonstrated that tetramycin could serve as an excellent alternative fungicide to control Phytophthora blight of pepper.
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Affiliation(s)
- Dicheng Ma
- College of Plant Protection, Shandong Agricultural University, Shandong Provincial Key Laboratory for Biology of Vegetable Diseases and Insect Pests, Tai'an, Shandong 271018, P.R. China
| | - Jiamei Zhu
- College of Plant Protection, Shandong Agricultural University, Shandong Provincial Key Laboratory for Biology of Vegetable Diseases and Insect Pests, Tai'an, Shandong 271018, P.R. China
| | - Leiming He
- College of Plant Protection, Shandong Agricultural University, Shandong Provincial Key Laboratory for Biology of Vegetable Diseases and Insect Pests, Tai'an, Shandong 271018, P.R. China
| | - Kaidi Cui
- College of Plant Protection, Shandong Agricultural University, Shandong Provincial Key Laboratory for Biology of Vegetable Diseases and Insect Pests, Tai'an, Shandong 271018, P.R. China
| | - Wei Mu
- College of Plant Protection, Shandong Agricultural University, Shandong Provincial Key Laboratory for Biology of Vegetable Diseases and Insect Pests, Tai'an, Shandong 271018, P.R. China
| | - Feng Liu
- College of Plant Protection, Shandong Agricultural University, Shandong Provincial Key Laboratory for Biology of Vegetable Diseases and Insect Pests, Tai'an, Shandong 271018, P.R. China
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103
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Ju Y, Son KH, Jin C, Hwang BS, Park DJ, Kim CJ. Statistical optimization of culture medium for improved production of antimicrobial compound by Streptomyces rimosus AG-P1441. Food Sci Biotechnol 2018; 27:581-590. [PMID: 30263783 PMCID: PMC6049630 DOI: 10.1007/s10068-017-0257-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Revised: 10/29/2017] [Accepted: 11/09/2017] [Indexed: 11/25/2022] Open
Abstract
The nutritional requirements for antimicrobial activity of Streptomyces rimosus AG-P1441 were optimized using statistically-based experimental designs at a flask level. Based on a one-factor-at-a-time (OFAT) approach, glucose, corn starch and soybean meal were identified as the carbon and nitrogen sources having a significant effect on antimicrobial productivity. As a result of investigating the effect of glucose concentration, the highest antimicrobial activity was observed at 3% concentration. Response surface methodology (RSM) was then applied to optimize the growth medium components (corn starch, soybean meal, MgCl2 and glutamate). Antimicrobial productivity increased sharply when the medium consisted of 3% glucose, 3.5% corn starch, 2.5% soybean meal, 1.2 mM MgCl2 and 5.9 mM glutamate. The fermentation using optimized culture medium in a 5-L bioreactor allowed a significant increase in antimicrobial activity, evaluated by the paper disc assay, revealed a 29 mm inhibition zone diameter against Phytophthora capsici.
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Affiliation(s)
- Yoonjung Ju
- Industrial Biomaterial Research Center, Korea Research Institute of Bioscience and Biotechnology, 125 Gwahak-ro, Yuseong-gu, Daejeon, 34141 Korea
| | - Kwang-Hee Son
- Industrial Biomaterial Research Center, Korea Research Institute of Bioscience and Biotechnology, 125 Gwahak-ro, Yuseong-gu, Daejeon, 34141 Korea
| | - Chunzhi Jin
- Industrial Biomaterial Research Center, Korea Research Institute of Bioscience and Biotechnology, 125 Gwahak-ro, Yuseong-gu, Daejeon, 34141 Korea
- University of Science and Technology, 217 Gajeong-ro, Yuseong-gu, Daejeon, 34113 Korea
| | - Byung Soon Hwang
- Industrial Biomaterial Research Center, Korea Research Institute of Bioscience and Biotechnology, 125 Gwahak-ro, Yuseong-gu, Daejeon, 34141 Korea
| | - Dong-Jin Park
- Industrial Biomaterial Research Center, Korea Research Institute of Bioscience and Biotechnology, 125 Gwahak-ro, Yuseong-gu, Daejeon, 34141 Korea
| | - Chang-Jin Kim
- Industrial Biomaterial Research Center, Korea Research Institute of Bioscience and Biotechnology, 125 Gwahak-ro, Yuseong-gu, Daejeon, 34141 Korea
- University of Science and Technology, 217 Gajeong-ro, Yuseong-gu, Daejeon, 34113 Korea
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104
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Khalaf EM, Raizada MN. Bacterial Seed Endophytes of Domesticated Cucurbits Antagonize Fungal and Oomycete Pathogens Including Powdery Mildew. Front Microbiol 2018; 9:42. [PMID: 29459850 PMCID: PMC5807410 DOI: 10.3389/fmicb.2018.00042] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2017] [Accepted: 01/09/2018] [Indexed: 01/28/2023] Open
Abstract
The cucurbit vegetables, including cucumbers, melons and pumpkins, have been cultivated for thousands of years without fungicides. However, their seed germination stage is prone to be infected by soil-borne fungal and oomycete pathogens. Endophytes are symbionts that reside inside plant tissues including seeds. Seed endophytes are founders of the juvenile plant microbiome and can promote host defense at seed germination and later stages. We previously isolated 169 bacterial endophytes associated with seeds of diverse cultivated cucurbits. We hypothesized that these endophytes can antagonize major fungal and oomycete pathogens. Here we tested the endophytes for in vitro antagonism (dual culture assays) against important soil-borne pathogens (Rhizoctonia solani, Fusarium graminearum, Phytophthora capsici, Pythium aphanideratum). The endophytes were also assayed in planta (leaf disk and detached leaf bioassays) for antagonism against a foliar pathogen of global importance, Podosphaera fuliginea, the causative agent of cucurbit powdery mildew. The endophytes were further tested in vitro for secretion of volatile organic compounds (VOCs) known to induce plant defense. Extracellular ribonuclease activity was also tested, as a subset of pathogenesis-related (PR) proteins of plant hosts implicated in suppression of fungal pathogens, displays ribonuclease activity. An unexpected majority of the endophytes (70%, 118/169) exhibited antagonism to the five phytopathogens, of which 68% (50/73) of in vitro antagonists belong to the genera Bacillus and Paenibacillus. All Lactococcus and Pantoea endophytes exhibited anti-oomycete activity. However, amongst the most effective inoculants against Podosphaera fuliginea were Pediococcus and Pantoea endophytes. Interestingly, 67% (113/169) of endophytes emitted host defense inducing VOCs (acetoin/diacetyl) and 62% (104/169) secreted extracellular ribonucleases in vitro, respectively. These results show that seeds of cultivated cucurbits package microbes with significant disease-suppression potential. As seeds can act as vectors for genetic transmission of endophytes across host generations, it is interesting to hypothesize whether humans, when selecting seeds of healthy hosts, may have inadvertently selected for disease-suppressing seed endophytes. As the majority of pathogen-suppressing endophytes belong to Bacillus and Paenibacillus, and since Bacilli are widely used as commercial biocontrol agents of vegetables, we propose that these agents are mimicking the ecological niche established by their endophytic cousins.
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Affiliation(s)
- Eman M. Khalaf
- Department of Plant Agriculture, University of Guelph, Guelph, ON, Canada
- Department of Microbiology and Immunology, Faculty of Pharmacy, Damanhour University, Damanhour, Egypt
| | - Manish N. Raizada
- Department of Plant Agriculture, University of Guelph, Guelph, ON, Canada
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105
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Kousik CS, Ikerd JL, Turechek WW. Development of Phytophthora Fruit Rot Caused by Phytophthora capsici on Resistant and Susceptible Watermelon Fruit of Different Ages. PLANT DISEASE 2018; 102:370-374. [PMID: 30673515 DOI: 10.1094/pdis-06-17-0898-re] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Watermelon is an important crop grown in 44 states in the United States. Phytophthora fruit rot caused by Phytophthora capsici is a serious disease in the southeastern U.S.A., where over 50% of the watermelons are produced. The disease has resulted in severe losses to watermelon growers, especially in Georgia, South Carolina, and North Carolina during the past few years. Several fruit rot-resistant watermelon germplasm lines have been developed for use in breeding programs. To evaluate the development of Phytophthora fruit rot on fruit of different ages, plants of fruit rot-resistant and susceptible lines were planted at weekly intervals for five consecutive weeks in experiments conducted over three years (2011 to 2013). Flowers were routinely inspected and hand pollinated to ensure having fruit of different ages. In each year, different aged fruit were harvested on the same day and inoculated with a 5-mm agar plug from an actively growing colony of P. capsici. Inoculated fruit were maintained in a room set to conditions conducive for disease development (>95% relative humidity, 26 ± 2°C). After 5 days, lesion diameter and intensity of sporulation was recorded for each fruit. Lesion diameter and sporulation intensity were significantly greater on fruit of susceptible lines compared with resistant lines. Fruit age did not have an effect on either measurement on susceptible (Sugar Baby) or resistant lines (PI 560020 and PI 595203). Our results showed that resistance to Phytophthora fruit rot in watermelon was not correlated with fruit age.
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Affiliation(s)
- Chandrasekar S Kousik
- United States Department of Agriculture, Agricultural Research Service, U.S. Vegetable Laboratory, 2700 Savannah Highway, Charleston, SC 29414
| | - Jennifer L Ikerd
- United States Department of Agriculture, Agricultural Research Service, U.S. Vegetable Laboratory, 2700 Savannah Highway, Charleston, SC 29414
| | - William W Turechek
- United States Department of Agriculture, Agricultural Research Service, U.S. Horticultural Research Laboratory, Fort Pierce, FL 34945
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106
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Simamora AV, Paap T, Howard K, Stukely MJC, Hardy GESJ, Burgess TI. Phytophthora Contamination in a Nursery and Its Potential Dispersal into the Natural Environment. PLANT DISEASE 2018; 102:132-139. [PMID: 30673463 DOI: 10.1094/pdis-05-17-0689-re] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
A detailed site investigation of a eucalypt nursery suffering disease losses revealed the causal agent to be Phytophthora boodjera. The pathogen was detected in vegetation surrounding the nursery production area, including the lawn, under the production benches during the growing season, and, most importantly, from plant debris in used trays. However, it was not found in the container substrate, water supplies, or production equipment or on the workers themselves. The sterilization methods used by the nursery were shown to be ineffective, indicating that a more rigorous method was required. Boiling trays for 15 min or steaming at 65°C for 60 min eradicated P. boodjera. This pathogen was more pathogenic to the eucalypts tested in their early seedling stage than P. cinnamomi. Tracing of out-planting to revegetation sites showed that P. boodjera was able to spread into the environment. Dispersal via out-planting to native vegetation may affect seedling recruitment and drive long-term shifts in native plant species. Inadequate nursery hygiene increases the risk of an outbreak and can limit the success of biosecurity efforts as well as damage conservation efforts.
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Affiliation(s)
- Agnes V Simamora
- Centre for Phytophthora Science and Management, School of Veterinary and Life Sciences, Murdoch University, Perth, WA, 6150, Australia; and Faculty of Agriculture, University of Nusa Cendana, Kupang, Indonesia
| | - Trudy Paap
- Centre for Phytophthora Science and Management, School of Veterinary and Life Sciences, Murdoch University
| | - Kay Howard
- Centre for Phytophthora Science and Management, School of Veterinary and Life Sciences, Murdoch University
| | - Michael J C Stukely
- Science and Conservation Division, Department of Parks and Wildlife, Bentley Delivery Centre, WA 6983, Australia
| | - Giles E St J Hardy
- Centre for Phytophthora Science and Management, School of Veterinary and Life Sciences, Murdoch University
| | - Treena I Burgess
- Centre for Phytophthora Science and Management, School of Veterinary and Life Sciences, Murdoch University
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107
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Kim S, Park J, Yeom SI, Kim YM, Seo E, Kim KT, Kim MS, Lee JM, Cheong K, Shin HS, Kim SB, Han K, Lee J, Park M, Lee HA, Lee HY, Lee Y, Oh S, Lee JH, Choi E, Choi E, Lee SE, Jeon J, Kim H, Choi G, Song H, Lee J, Lee SC, Kwon JK, Lee HY, Koo N, Hong Y, Kim RW, Kang WH, Huh JH, Kang BC, Yang TJ, Lee YH, Bennetzen JL, Choi D. New reference genome sequences of hot pepper reveal the massive evolution of plant disease-resistance genes by retroduplication. Genome Biol 2017; 18:210. [PMID: 29089032 DOI: 10.1007/s13580-019-00157-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Revised: 06/19/2019] [Accepted: 10/06/2017] [Indexed: 05/24/2023] Open
Abstract
BACKGROUND Transposable elements are major evolutionary forces which can cause new genome structure and species diversification. The role of transposable elements in the expansion of nucleotide-binding and leucine-rich-repeat proteins (NLRs), the major disease-resistance gene families, has been unexplored in plants. RESULTS We report two high-quality de novo genomes (Capsicum baccatum and C. chinense) and an improved reference genome (C. annuum) for peppers. Dynamic genome rearrangements involving translocations among chromosomes 3, 5, and 9 were detected in comparison between C. baccatum and the two other peppers. The amplification of athila LTR-retrotransposons, members of the gypsy superfamily, led to genome expansion in C. baccatum. In-depth genome-wide comparison of genes and repeats unveiled that the copy numbers of NLRs were greatly increased by LTR-retrotransposon-mediated retroduplication. Moreover, retroduplicated NLRs are abundant across the angiosperms and, in most cases, are lineage-specific. CONCLUSIONS Our study reveals that retroduplication has played key roles for the massive emergence of NLR genes including functional disease-resistance genes in pepper plants.
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Affiliation(s)
- Seungill Kim
- Department of Plant Science, Plant Genomics and Breeding Institute, Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul, 08826, South Korea
| | - Jieun Park
- Department of Plant Science, Plant Genomics and Breeding Institute, Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul, 08826, South Korea
- Interdisciplinary Program in Agricultural Genomics, Seoul National University, Seoul, 08826, South Korea
| | - Seon-In Yeom
- Department of Agricultural Plant Science, Institute of Agriculture & Life Science, Gyeongsang National University, Jinju, 52828, South Korea
| | - Yong-Min Kim
- Korean Bioinformation Center, Korea Research Institute of Bioscience and Biotechnology, Daejon, 34141, South Korea
| | - Eunyoung Seo
- Department of Plant Science, Plant Genomics and Breeding Institute, Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul, 08826, South Korea
| | - Ki-Tae Kim
- Department of Agricultural Biotechnology, Seoul National University, Seoul, 08826, South Korea
| | - Myung-Shin Kim
- Department of Plant Science, Plant Genomics and Breeding Institute, Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul, 08826, South Korea
| | - Je Min Lee
- Department of Horticultural Science, Kyungpook National University, Daegu, 41566, South Korea
| | - Kyeongchae Cheong
- Interdisciplinary Program in Agricultural Genomics, Seoul National University, Seoul, 08826, South Korea
- Department of Agricultural Biotechnology, Seoul National University, Seoul, 08826, South Korea
| | - Ho-Sub Shin
- Department of Plant Science, Plant Genomics and Breeding Institute, Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul, 08826, South Korea
| | - Saet-Byul Kim
- Department of Plant Science, Plant Genomics and Breeding Institute, Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul, 08826, South Korea
| | - Koeun Han
- Department of Plant Science, Plant Genomics and Breeding Institute, Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul, 08826, South Korea
- Vegetable Breeding Research Center, Seoul National University, Seoul, 08826, South Korea
| | - Jundae Lee
- Department of Horticulture, Chonbuk National University, Jeonju, 54896, South Korea
| | - Minkyu Park
- Department of Genetics, University of Georgia, Athens, GA, 30602-7223, USA
| | - Hyun-Ah Lee
- Department of Plant Science, Plant Genomics and Breeding Institute, Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul, 08826, South Korea
| | - Hye-Young Lee
- Department of Plant Science, Plant Genomics and Breeding Institute, Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul, 08826, South Korea
| | - Youngsill Lee
- Department of Plant Science, Plant Genomics and Breeding Institute, Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul, 08826, South Korea
| | - Soohyun Oh
- Department of Plant Science, Plant Genomics and Breeding Institute, Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul, 08826, South Korea
| | - Joo Hyun Lee
- Department of Plant Science, Plant Genomics and Breeding Institute, Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul, 08826, South Korea
| | - Eunhye Choi
- Department of Plant Science, Plant Genomics and Breeding Institute, Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul, 08826, South Korea
| | - Eunbi Choi
- Department of Plant Science, Plant Genomics and Breeding Institute, Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul, 08826, South Korea
| | - So Eui Lee
- Department of Plant Science, Plant Genomics and Breeding Institute, Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul, 08826, South Korea
| | - Jongbum Jeon
- Interdisciplinary Program in Agricultural Genomics, Seoul National University, Seoul, 08826, South Korea
| | - Hyunbin Kim
- Interdisciplinary Program in Agricultural Genomics, Seoul National University, Seoul, 08826, South Korea
| | - Gobong Choi
- Interdisciplinary Program in Agricultural Genomics, Seoul National University, Seoul, 08826, South Korea
| | - Hyeunjeong Song
- Interdisciplinary Program in Agricultural Genomics, Seoul National University, Seoul, 08826, South Korea
| | - JunKi Lee
- Department of Plant Science, Plant Genomics and Breeding Institute, Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul, 08826, South Korea
| | - Sang-Choon Lee
- Department of Plant Science, Plant Genomics and Breeding Institute, Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul, 08826, South Korea
| | - Jin-Kyung Kwon
- Department of Plant Science, Plant Genomics and Breeding Institute, Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul, 08826, South Korea
- Vegetable Breeding Research Center, Seoul National University, Seoul, 08826, South Korea
| | - Hea-Young Lee
- Department of Plant Science, Plant Genomics and Breeding Institute, Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul, 08826, South Korea
- Vegetable Breeding Research Center, Seoul National University, Seoul, 08826, South Korea
| | - Namjin Koo
- Korean Bioinformation Center, Korea Research Institute of Bioscience and Biotechnology, Daejon, 34141, South Korea
| | - Yunji Hong
- Korean Bioinformation Center, Korea Research Institute of Bioscience and Biotechnology, Daejon, 34141, South Korea
| | - Ryan W Kim
- Korean Bioinformation Center, Korea Research Institute of Bioscience and Biotechnology, Daejon, 34141, South Korea
| | - Won-Hee Kang
- Department of Agricultural Plant Science, Institute of Agriculture & Life Science, Gyeongsang National University, Jinju, 52828, South Korea
| | - Jin Hoe Huh
- Department of Plant Science, Plant Genomics and Breeding Institute, Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul, 08826, South Korea
| | - Byoung-Cheorl Kang
- Department of Plant Science, Plant Genomics and Breeding Institute, Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul, 08826, South Korea
- Vegetable Breeding Research Center, Seoul National University, Seoul, 08826, South Korea
| | - Tae-Jin Yang
- Department of Plant Science, Plant Genomics and Breeding Institute, Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul, 08826, South Korea
| | - Yong-Hwan Lee
- Interdisciplinary Program in Agricultural Genomics, Seoul National University, Seoul, 08826, South Korea
- Department of Agricultural Biotechnology, Seoul National University, Seoul, 08826, South Korea
| | | | - Doil Choi
- Department of Plant Science, Plant Genomics and Breeding Institute, Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul, 08826, South Korea.
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108
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Genetic diversity of Phytophthora capsici recovered from Massachusetts between 1997 and 2014. Mycol Prog 2017. [DOI: 10.1007/s11557-017-1334-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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109
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Barchenger DW, Lamour KH, Sheu ZM, Shrestha S, Kumar S, Lin SW, Burlakoti R, Bosland PW. Intra- and Intergenomic variation of Ploidy and Clonality characterize Phytophthora capsici on Capsicum sp. in Taiwan. Mycol Prog 2017. [DOI: 10.1007/s11557-017-1330-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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110
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Liu X, Ouyang C, Wang Q, Li Y, Yan D, Yang D, Fang W, Cao A, Guo M. Effects of oil extracts of Eupatorium adenophorum on Phytophthora capsici and other plant pathogenic fungi in vitro. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2017; 140:90-96. [PMID: 28755701 DOI: 10.1016/j.pestbp.2017.06.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 06/19/2017] [Accepted: 06/23/2017] [Indexed: 06/07/2023]
Abstract
The antifungal activity of oils extracted from Eupatorium adenophorum was tested against five phytopathogens in vitro. Oil extracts inhibited the mycelial growth of Phytophthora capsici which causes phytophthora blight in pepper. The minimum inhibitory concentration of oils against P. capsici was 500μg/ml after 7days incubation. At the ultrastructural level, oil extracts caused complete disorganization of intracellular organelles, cytoplasm depletion, disruption of cytoplasmic membranes and the cell wall. Membrane permeability increased with the increasing concentration of oil extracts. These results suggested that these oil extracts exhibited multiple modes of action including disruption of the cell membrane system. Furthermore, oil extracts combined with synthetic fungicides synergistically inhibited mycelial growth of P. capsici, which creates the possibility of reducing fungicide concentration needed to successfully control phytophthora blight in commercial pepper production. This study's use of multiple methods of analysis has increased our understanding of the mode of action of E. adenophorum oil extracts against P. capsici.
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Affiliation(s)
- Xiaoman Liu
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Canbin Ouyang
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Qiuxia Wang
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yuan Li
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Dongdong Yan
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Dongsheng Yang
- Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Wensheng Fang
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Aocheng Cao
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China.
| | - Meixia Guo
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
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111
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Krasnow CS, Hammerschmidt R, Hausbeck MK. Characteristics of Resistance to Phytophthora Root and Crown Rot in Cucurbita pepo. PLANT DISEASE 2017; 101:659-665. [PMID: 30678567 DOI: 10.1094/pdis-06-16-0867-re] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Root and crown rot incited by Phytophthora capsici causes considerable annual losses in squash-producing regions in the United States. 'Spineless Perfection' zucchini and 'Cougar' straightneck squash (Cucurbita pepo L.), partially resistant and susceptible to root and crown rot, respectively, were investigated for differences in root and crown physical factors and the histology of crown infection by P. capsici. The pH and titratable acidity of healthy root and crown tissue from tissue extracts were not significantly different between cultivars (P = 0.05). Crude fiber content (%) of blended and oven-dried root and crown tissue from healthy plants was similar between cultivars. However, dry matter (%) was highest for Cougar (P = 0.05). Colonies of P. capsici grown from mycelial plugs in root exudates collected from each cultivar were similar in diameter. Whole mounts and histological sections of healthy and infected crown tissue revealed that vascular bundles and metaxylem vessels were more abundant in crowns of Spineless Perfection than Cougar. Twelve to 48 h post inoculation (hpi), mycelia in the crown of each cultivar was limited to the cortex and hypodermal tissue. By 72 hpi, hyphae were observed in the cortex and endodermal tissue of Cougar and were concentrated in the phloem and parenchyma cells surrounding vascular bundles. Mycelia were limited to the outer cortex in Spineless Perfection. Mycelia and occluding material were present in the majority of metaxylem vessels of Cougar but not Spineless Perfection at 92 hpi; dissolution of parenchyma cells surrounding vascular bundles was apparent in Cougar. The vascular occlusions observed in Cougar may be responsible for plant wilting, a common disease symptom. Additional straightneck, crookneck, scallop, and acorn squash (C. pepo ssp. ovifera), and zucchini, marrow, and pumpkin (C. pepo ssp. pepo) cultivars were evaluated in a greenhouse study for resistance to root and crown rot. Cucurbita pepo ssp. ovifera cultivars were significantly more susceptible than C. pepo ssp. pepo to root and crown rot (P < 0.0001). Growing C. pepo ssp. pepo cultivars may be beneficial in an integrated Phytophthora management program.
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Affiliation(s)
- Charles S Krasnow
- Department of Plant, Soil, and Microbial Sciences, Michigan State University, East Lansing 48824
| | - Raymond Hammerschmidt
- Department of Plant, Soil, and Microbial Sciences, Michigan State University, East Lansing 48824
| | - Mary K Hausbeck
- Department of Plant, Soil, and Microbial Sciences, Michigan State University, East Lansing 48824
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Jeong JJ, Lee DW, Park B, Sang MK, Choi IG, Kim KD. Chryseobacterium cucumeris sp. nov., an endophyte isolated from cucumber (Cucumis sativus L.) root, and emended description of Chryseobacterium arthrosphaerae. Int J Syst Evol Microbiol 2017; 67:610-616. [PMID: 27902284 DOI: 10.1099/ijsem.0.001670] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The Gram-stain-negative, yellow-pigmented, rod-shaped bacterial strain GSE06T, isolated from the surface-sterilized root of a cucumber plant grown in a field in Gunsan, Korea, was characterized by not only cultural and morphological features but also physiological, biochemical and molecular analyses. Phylogenetic analyses based on 16S rRNA gene sequences revealed that strain GSE06T was most closely related to species of the genus Chryseobacterium. Furthermore, strain GSE06T exhibited the highest sequence similarities with the type strains Chryseobacterium indologenes ATCC 29897T (98.9 %), Chryseobacterium gleum ATCC 35910T (98.8 %), Chryseobacterium arthrosphaerae CC-VM-7T (98.7 %), Chryseobacterium contaminans C26T (98.5 %), Chryseobacterium artocarpi UTM-3T (98.3 %), and Chryseobacterium gallinarum 100T (97.9 %). Average nucleotide identity values between genome sequences of strain GSE06T and the above-mentioned reference strains ranged from 81.2 to 86.9 %, which were lower than the threshold of 95 % (corresponding to a DNA-DNA reassociation value of 70 %). The DNA G+C content of strain GSE06T was 36.1 mol%; the predominant respiratory quinone of the strain was MK-6. The major fatty acids were iso-C15 : 0, summed feature 9 (iso-C17 : 1ω9c), summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) and iso-C17 : 0 3-OH. The major polar lipids were phosphatidylethanolamine, three aminolipids, one aminophospholipid, four glycolipids and one unidentified lipid. These results of phenotypic and genotypic characteristics could differentiate strain GSE06T from closely related type strains belonging to the genus Chryseobacterium. Thus, strain GSE06T is proposed as a representative of a novel species in the genus Chryseobacterium, Chryseobacterium cucumeris sp. nov. The type strain is GSE06T (=KACC 18798T=JCM 31422T).
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Affiliation(s)
- Jin-Ju Jeong
- Laboratory of Plant Disease and Biocontrol, College of Life Sciences and Biotechnology, Korea University, Seoul 02841, Republic of Korea
| | - Dong Wan Lee
- Department of Biosystems and Biotechnology, Korea University, Seoul 02841, Republic of Korea
| | - Byeonghyeok Park
- Department of Biotechnology, Korea University, Seoul 02841, Republic of Korea
| | - Mee Kyung Sang
- Present address: Division of Agricultural Microbiology, National Academy of Agricultural Science, Rural Development Administration, Jeonju 55365, Republic of Korea.,Laboratory of Plant Disease and Biocontrol, College of Life Sciences and Biotechnology, Korea University, Seoul 02841, Republic of Korea
| | - In-Geol Choi
- Department of Biotechnology, Korea University, Seoul 02841, Republic of Korea
| | - Ki Deok Kim
- Laboratory of Plant Disease and Biocontrol, College of Life Sciences and Biotechnology, Korea University, Seoul 02841, Republic of Korea
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113
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Pang Z, Srivastava V, Liu X, Bulone V. Quantitative proteomics links metabolic pathways to specific developmental stages of the plant-pathogenic oomycete Phytophthora capsici. MOLECULAR PLANT PATHOLOGY 2017; 18:378-390. [PMID: 27019332 PMCID: PMC6638298 DOI: 10.1111/mpp.12406] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Revised: 03/21/2016] [Accepted: 03/24/2016] [Indexed: 05/16/2023]
Abstract
The oomycete Phytophthora capsici is a plant pathogen responsible for important losses to vegetable production worldwide. Its asexual reproduction plays an important role in the rapid propagation and spread of the disease in the field. A global proteomics study was conducted to compare two key asexual life stages of P. capsici, i.e. the mycelium and cysts, to identify stage-specific biochemical processes. A total of 1200 proteins was identified using qualitative and quantitative proteomics. The transcript abundance of some of the enriched proteins was also analysed by quantitative real-time polymerase chain reaction. Seventy-three proteins exhibited different levels of abundance between the mycelium and cysts. The proteins enriched in the mycelium are mainly associated with glycolysis, the tricarboxylic acid (or citric acid) cycle and the pentose phosphate pathway, providing the energy required for the biosynthesis of cellular building blocks and hyphal growth. In contrast, the proteins that are predominant in cysts are essentially involved in fatty acid degradation, suggesting that the early infection stage of the pathogen relies primarily on fatty acid degradation for energy production. The data provide a better understanding of P. capsici biology and suggest potential metabolic targets at the two different developmental stages for disease control.
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Affiliation(s)
- Zhili Pang
- Department of Plant Pathology, College of Agriculture and BiotechnologyChina Agricultural UniversityBeijing100193China
- Division of GlycoscienceRoyal Institute of Technology (KTH), AlbaNova University CentreStockholmSE‐10691Sweden
| | - Vaibhav Srivastava
- Division of GlycoscienceRoyal Institute of Technology (KTH), AlbaNova University CentreStockholmSE‐10691Sweden
| | - Xili Liu
- Department of Plant Pathology, College of Agriculture and BiotechnologyChina Agricultural UniversityBeijing100193China
| | - Vincent Bulone
- Division of GlycoscienceRoyal Institute of Technology (KTH), AlbaNova University CentreStockholmSE‐10691Sweden
- Australian Research Council Centre of Excellence in Plant Cell Walls, School of Agriculture, Food and WineUniversity of Adelaide, Waite CampusUrrbraeSA5064Australia
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114
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Carlson MO, Gazave E, Gore MA, Smart CD. Temporal Genetic Dynamics of an Experimental, Biparental Field Population of Phytophthora capsici. Front Genet 2017; 8:26. [PMID: 28348576 PMCID: PMC5347166 DOI: 10.3389/fgene.2017.00026] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Accepted: 02/20/2017] [Indexed: 01/01/2023] Open
Abstract
Defining the contributions of dispersal, reproductive mode, and mating system to the population structure of a pathogenic organism is essential to estimating its evolutionary potential. After introduction of the devastating plant pathogen, Phytophthora capsici, into a grower's field, a lack of aerial spore dispersal restricts migration. Once established, coexistence of both mating types results in formation of overwintering recombinant oospores, engendering persistent pathogen populations. To mimic these conditions, in 2008, we inoculated a field with two P. capsici isolates of opposite mating type. We analyzed pathogenic isolates collected in 2009-2013 from this experimental population, using genome-wide single-nucleotide polymorphism markers. By tracking heterozygosity across years, we show that the population underwent a generational shift; transitioning from exclusively F1 in 2009-2010, to multi-generational in 2011, and ultimately all inbred in 2012-2013. Survival of F1 oospores, characterized by heterozygosity excess, coupled with a low rate of selfing, delayed declines in heterozygosity due to inbreeding and attainment of equilibrium genotypic frequencies. Large allele and haplotype frequency changes in specific genomic regions accompanied the generational shift, representing putative signatures of selection. Finally, we identified an approximately 1.6 Mb region associated with mating type determination, constituting the first detailed genomic analysis of a mating type region (MTR) in Phytophthora. Segregation patterns in the MTR exhibited tropes of sex-linkage, where maintenance of allele frequency differences between isolates of opposite mating type was associated with elevated heterozygosity despite inbreeding. Characterizing the trajectory of this experimental system provides key insights into the processes driving persistent, sexual pathogen populations.
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Affiliation(s)
- Maryn O. Carlson
- Plant Pathology and Plant-Microbe Biology Section, School of Integrative Plant Science, Cornell UniversityGeneva, NY, USA
- Plant Breeding and Genetics Section, School of Integrative Plant Science, Cornell UniversityIthaca, NY, USA
| | - Elodie Gazave
- Plant Breeding and Genetics Section, School of Integrative Plant Science, Cornell UniversityIthaca, NY, USA
| | - Michael A. Gore
- Plant Breeding and Genetics Section, School of Integrative Plant Science, Cornell UniversityIthaca, NY, USA
| | - Christine D. Smart
- Plant Pathology and Plant-Microbe Biology Section, School of Integrative Plant Science, Cornell UniversityGeneva, NY, USA
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115
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Vega-Arreguín JC, Shimada-Beltrán H, Sevillano-Serrano J, Moffett P. Non-host Plant Resistance against Phytophthora capsici Is Mediated in Part by Members of the I2 R Gene Family in Nicotiana spp. FRONTIERS IN PLANT SCIENCE 2017; 8:205. [PMID: 28261255 PMCID: PMC5309224 DOI: 10.3389/fpls.2017.00205] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Accepted: 02/03/2017] [Indexed: 05/29/2023]
Abstract
The identification of host genes associated with resistance to Phytophthora capsici is crucial to developing strategies of control against this oomycete pathogen. Since there are few sources of resistance to P. capsici in crop plants, non-host plants represent a promising source of resistance genes as well as excellent models to study P. capsici - plant interactions. We have previously shown that non-host resistance to P. capsici in Nicotiana spp. is mediated by the recognition of a specific P. capsici effector protein, PcAvr3a1 in a manner that suggests the involvement of a cognate disease resistance (R) genes. Here, we have used virus-induced gene silencing (VIGS) and transgenic tobacco plants expressing dsRNA in Nicotiana spp. to identify candidate R genes that mediate non-host resistance to P. capsici. Silencing of members of the I2 multigene family in the partially resistant plant N. edwardsonii and in the resistant N. tabacum resulted in compromised resistance to P. capsici. VIGS of two other components required for R gene-mediated resistance, EDS1 and SGT1, also enhanced susceptibility to P. capsici in N. edwardsonii, as well as in the susceptible plants N. benthamiana and N. clevelandii. The silencing of I2 family members in N. tabacum also compromised the recognition of PcAvr3a1. These results indicate that in this case, non-host resistance is mediated by the same components normally associated with race-specific resistance.
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Affiliation(s)
- Julio C. Vega-Arreguín
- Boyce Thompson Institute for Plant Research, IthacaNY, USA
- Laboratorio de Ciencias Agrogenómicas, Escuela Nacional de Estudios Superiores – León, Universidad Nacional Autónoma de MexicoLeón, Mexico
| | - Harumi Shimada-Beltrán
- Laboratorio de Ciencias Agrogenómicas, Escuela Nacional de Estudios Superiores – León, Universidad Nacional Autónoma de MexicoLeón, Mexico
| | - Jacobo Sevillano-Serrano
- Laboratorio de Ciencias Agrogenómicas, Escuela Nacional de Estudios Superiores – León, Universidad Nacional Autónoma de MexicoLeón, Mexico
| | - Peter Moffett
- Boyce Thompson Institute for Plant Research, IthacaNY, USA
- Département de Biologie, Faculté des Sciences, Université de Sherbrooke, SherbrookeQC, Canada
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116
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Gobena D, Roig J, Galmarini C, Hulvey J, Lamour K. Genetic diversity ofPhytophthora capsiciisolates from pepper and pumpkin in Argentina. Mycologia 2017; 104:102-7. [DOI: 10.3852/11-147] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Daniel Gobena
- Genome Science and Technology Graduate Program, University of Tennessee, Knoxville, Tennessee
| | | | | | - Jon Hulvey
- Department of Plant, Soil, and Insect Sciences, University of Massachusetts, Amherst, Massachusetts
| | - Kurt Lamour
- Department of Entomology and Plant Pathology, University of Tennessee, Knoxville Tennessee
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117
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Wang XW, Guo LY, Han M, Shan K. Diversity, evolution and expression profiles of histone acetyltransferases and deacetylases in oomycetes. BMC Genomics 2016; 17:927. [PMID: 27852223 PMCID: PMC5112689 DOI: 10.1186/s12864-016-3285-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Accepted: 11/09/2016] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Oomycetes are a group of fungus-like eukaryotes with diverse microorganisms living in marine, freshwater and terrestrial environments. Many of them are important pathogens of plants and animals, causing severe economic losses. Based on previous study, gene expression in eukaryotic cells is regulated by epigenetic mechanisms such as DNA methylation and histone modification. However, little is known about epigenetic mechanisms of oomycetes. RESULTS In this study, we investigated the candidate genes in regulating histone acetylation in oomycetes genomes through bioinformatics approaches and identified a group of diverse histone acetyltransferases (HATs) and histone deacetylases (HDACs), along with three putative novel HATs. Phylogenetic analyses suggested that most of these oomycetes HATs and HDACs derived from distinct evolutionary ancestors. Phylogenetic based analysis revealed the complex and distinct patterns of duplications and losses of HATs and HDACs in oomycetes. Moreover, gene expression analysis unveiled the specific expression patterns of the 33 HATs and 11 HDACs of Phytophthora infestans during the stages of development, infection and stress response. CONCLUSIONS In this study, we reveal the structure, diversity and the phylogeny of HATs and HDACs of oomycetes. By analyzing the expression data, we provide an overview of the specific biological stages of these genes involved. Our datasets provide useful inputs to help explore the epigenetic mechanisms and the relationship between genomes and phenotypes of oomycetes.
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Affiliation(s)
- Xiao-Wen Wang
- Department of Plant Pathology and the Ministry of Agriculture Key Laboratory for Plant Pathology, China Agricultural University, Beijing, 100193, China
| | - Li-Yun Guo
- Department of Plant Pathology and the Ministry of Agriculture Key Laboratory for Plant Pathology, China Agricultural University, Beijing, 100193, China.
| | - Miao Han
- Department of Plant Pathology and the Ministry of Agriculture Key Laboratory for Plant Pathology, China Agricultural University, Beijing, 100193, China
| | - Kun Shan
- Department of Plant Pathology and the Ministry of Agriculture Key Laboratory for Plant Pathology, China Agricultural University, Beijing, 100193, China
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118
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Jeon S, Krasnow CS, Kirby CK, Granke LL, Hausbeck MK, Zhang W. Transport and Retention of Phytophthora capsici Zoospores in Saturated Porous Media. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2016; 50:9270-9278. [PMID: 27517718 DOI: 10.1021/acs.est.6b01784] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Phytophthora capsici is an important plant pathogen capable of infecting several major vegetable crops. Water-induced P. capsici transport is considered to be a significant contributor to disease outbreaks and subsequent crop loss. However, little is known about factors controlling P. capsici zoospore transport in porous media, thus impeding our understanding of their environmental dispersal and development of filtration techniques for contaminated irrigation water. This study investigated the transport and retention of P. capsici zoospores in saturated columns packed with iron-oxide-coated sand (IOCS) or uncoated sand in Na(+) or Ca(2+) background solution at pH 7.7 ± 0.5 or 4.0 ± 0.3, in combination with XDLVO interaction energy calculations and microscopic visualizations. Significantly more encysted zoospores were retained in IOCS than in uncoated sand, and at pH 4.0 than at pH 7.7, which likely resulted from increased electrostatic attraction between zoospores and grain surface. At pH 7.7, up to 99% and 96% of the encysted zoospores were removed in IOCS and uncoated sand, respectively, due to a combination of strong surface attachment, pore straining, and adhesive interactions. Motile biflagellate zoospores were more readily transported than encysted zoospores, thus posing a greater dispersal and infection risk. This study has broad implications in environmental transport of Phytophthora zoospores in natural soils as well as in cost-effective engineered filtration systems.
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Affiliation(s)
| | | | | | - Leah L Granke
- Crop Protection Discovery, Dow AgroSciences , Indianapolis, Indiana 46268, United States
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119
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Wu D, Navet N, Liu Y, Uchida J, Tian M. Establishment of a simple and efficient Agrobacterium-mediated transformation system for Phytophthora palmivora. BMC Microbiol 2016; 16:204. [PMID: 27599726 PMCID: PMC5012004 DOI: 10.1186/s12866-016-0825-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2016] [Accepted: 08/30/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND As an agriculturally important oomycete genus, Phytophthora contains a large number of destructive plant pathogens that severely threaten agricultural production and natural ecosystems. Among them is the broad host range pathogen P. palmivora, which infects many economically important plant species. An essential way to dissect their pathogenesis mechanisms is genetic modification of candidate genes, which requires effective transformation systems. Four methods were developed for transformation of Phytophthora spp., including PEG(polyethylene glycol)/CaCl2 mediated protoplast transformation, electroporation of zoospores, microprojectile bombardment and Agrobacterium-mediated transformation (AMT). Among them, AMT has many advantages over the other methods such as easy handling and mainly generating single-copy integration in the genome. An AMT method previously reported for P. infestans and P. palmivora has barely been used in oomycete research due to low success and low reproducibility. RESULTS In this study, we report a simple and efficient AMT system for P. palmivora. Using this system, we were able to reproducibly generate over 40 transformants using zoospores collected from culture grown in a single 100 mm-diameter petri dish. The generated GFP transformants constitutively expressed GFP readily detectable using a fluorescence microscope. All of the transformants tested using Southern blot analysis contained a single-copy T-DNA insertion. CONCLUSIONS This system is highly effective and reproducible for transformation of P. palmivora and expected to be adaptable for transformation of additional Phytophthora spp. and other oomycetes. Its establishment will greatly accelerate their functional genomic studies.
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Affiliation(s)
- Dongliang Wu
- Department of Plant and Environmental Protection Sciences, University of Hawaii at Manoa, 3190 Maile Way, St. John 317, Honolulu, HI 96822 USA
| | - Natasha Navet
- Department of Plant and Environmental Protection Sciences, University of Hawaii at Manoa, 3190 Maile Way, St. John 317, Honolulu, HI 96822 USA
| | - Yingchao Liu
- Department of Plant and Environmental Protection Sciences, University of Hawaii at Manoa, 3190 Maile Way, St. John 317, Honolulu, HI 96822 USA
- Present Address: College of Plant Protection, Agricultural University of Hebei, Baoding, China
| | - Janice Uchida
- Department of Plant and Environmental Protection Sciences, University of Hawaii at Manoa, 3190 Maile Way, St. John 317, Honolulu, HI 96822 USA
| | - Miaoying Tian
- Department of Plant and Environmental Protection Sciences, University of Hawaii at Manoa, 3190 Maile Way, St. John 317, Honolulu, HI 96822 USA
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120
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Qu T, Grey TL, Csinos AS, Ji P. Translocation of Oxathiapiprolin in Bell Pepper Plants and Systemic Protection of Plants Against Phytophthora Blight. PLANT DISEASE 2016; 100:1931-1936. [PMID: 30682987 DOI: 10.1094/pdis-03-16-0370-re] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Production of bell pepper is seriously affected by Phytophthora capsici, the causal agent of Phytophthora blight. Limited approaches are available for effective management of the disease. Oxathiapiprolin is a fungicide recently registered in the United States that suppressed P. capsici and reduced Phytophthora blight on bell pepper significantly in our previous studies. It is unknown whether oxathiapiprolin translocates in bell pepper plants systemically after application. Experiments were conducted to determine uptake of oxathiapiprolin by bell pepper plants and its systemic movement in the plant. Quantification of oxathiapiprolin in plant tissues was conducted by high-performance liquid chromatography (HPLC) that detected the compound sensitively and selectively. Percentage of recovery of oxathiapiprolin from plant tissues was calculated by comparing the quantities in plant tissues determined by HPLC with known quantities of the compound added to the plant tissues. Recovery rates of oxathiapiprolin from pepper plant tissues ranged from 87.0 to 119.3%. When oxathiapiprolin was applied to roots of bell pepper plants grown in hydroculture, the compound was detected in the root within 4 h and in the cotyledon, first true leaf, and second true leaf within 8 h. It was detectable in the top new leaf 48 h after application to the root. In greenhouse studies with bell pepper plants grown in pots, oxathiapiprolin was applied as a soil drench at 100 and 400 μg/ml. The compound was detected in the root within 3 days and in the stem and first true leaf within 6 days when applied at 100 μg/ml. It was detected in the root, stem, first true leaf, and top new leaf within 3 days when applied at 400 μg/ml. Phytophthora blight on pepper foliage was significantly reduced when oxathiapiprolin was applied as a soil drench at 100 or 400 μg/ml under greenhouse conditions. This is the first report indicating systemic movement of oxathiapiprolin in pepper plants that provides useful information for designing fungicide application programs for effective management of the disease.
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Affiliation(s)
- Tianli Qu
- Chemistry and Pharmacy College, Qingdao Agricultural University, Shandong 266109, China; and Department of Plant Pathology, University of Georgia, Tifton 31794
| | - Timothy L Grey
- Department of Crop and Soil Sciences, University of Georgia
| | | | - Pingsheng Ji
- Department of Plant Pathology, University of Georgia, Tifton 31794
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121
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Wang Y, Sun Y, Zhang Y, Zhang X, Feng J. Antifungal Activity and Biochemical Response of Cuminic Acid against Phytophthora capsici Leonian. Molecules 2016; 21:E756. [PMID: 27294911 PMCID: PMC6274175 DOI: 10.3390/molecules21060756] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Revised: 06/03/2016] [Accepted: 06/06/2016] [Indexed: 11/26/2022] Open
Abstract
Phytophthora blight of pepper caused by Phytophthora capsici Leonian is a destructive disease throughout the world. Cuminic acid, extracted from the seed of Cuminum cyminum L., belongs to the benzoic acid chemical class. In this study, the sensitivity and biochemical response of P. capsici to cuminic acid was determined. The mean EC50 (50% effective concentration) values for cuminic acid in inhibiting mycelial growth and zoospore germination of the 54 studied P. capsici isolates were 14.54 ± 5.23 μg/mL and 6.97 ± 2.82 μg/mL, respectively. After treatment with cuminic acid, mycelial morphology, sporangium formation and mycelial respiration were significantly influenced; cell membrane permeability and DNA content increased markedly, but pyruvic acid content, adenosine triphosphate (ATP) content, and ATPase activity decreased compared with the untreated control. In pot experiments, cuminic acid exhibited both protective and curative activity. Importantly, POD and PAL activity of the pepper leaves increased after being treated with cuminic acid. These indicated that cuminic acid not only showed antifungal activity, but also could improve the defense capacity of the plants. All the results suggested that cuminic acid exhibits the potential to be developed as a new phytochemical fungicide, and this information increases our understanding of the mechanism of action of cuminic acid against Phytophthora capsici.
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Affiliation(s)
- Yong Wang
- Research and Development Center of Biorational Pesticides, Northwest A & F University, Yangling 712100, China.
| | - Yang Sun
- Research and Development Center of Biorational Pesticides, Northwest A & F University, Yangling 712100, China.
| | - Ying Zhang
- Research and Development Center of Biorational Pesticides, Northwest A & F University, Yangling 712100, China.
| | - Xing Zhang
- Research and Development Center of Biorational Pesticides, Northwest A & F University, Yangling 712100, China.
| | - Juntao Feng
- Research and Development Center of Biorational Pesticides, Northwest A & F University, Yangling 712100, China.
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122
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Miao J, Cai M, Dong X, Liu L, Lin D, Zhang C, Pang Z, Liu X. Resistance Assessment for Oxathiapiprolin in Phytophthora capsici and the Detection of a Point Mutation (G769W) in PcORP1 that Confers Resistance. Front Microbiol 2016; 7:615. [PMID: 27199944 PMCID: PMC4850160 DOI: 10.3389/fmicb.2016.00615] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Accepted: 04/14/2016] [Indexed: 01/07/2023] Open
Abstract
The potential for oxathiapiprolin resistance in Phytophthora capsici was evaluated. The baseline sensitivities of 175 isolates to oxathiapiprolin were initially determinated and found to conform to a unimodal curve with a mean EC50 value of 5.61 × 10(-4) μg/ml. Twelve stable oxathiapiprolin-resistant mutants were generated by fungicide adaptation in two sensitive isolates, LP3 and HNJZ10. The fitness of the LP3-mutants was found to be similar to or better than that of the parental isolate LP3, while the HNJZ10-mutants were found to have lost the capacity to produce zoospores. Taken together these results suggest that the risk of P. capsici developing resistance to oxathiapiprolin is moderate. Comparison of the PcORP1 genes in the LP3-mutants and wild-type parental isolate, which encode the target protein of oxathiapiprolin, revealed that a heterozygous mutation caused the amino acid substitution G769W. Transformation and expression of the mutated PcORP1-769W allele in the sensitive wild-type isolate BYA5 confirmed that the mutation in PcORP1 was responsible for the observed oxathiapiprolin resistance. Finally diagnostic tests including As-PCR and CAPs were developed to detect the oxathiapiprolin resistance resulting from the G769W point mutation in field populations of P. capsici.
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Affiliation(s)
| | | | | | | | | | | | | | - Xili Liu
- Department of Plant Pathology, China Agricultural UniversityBeijing, China
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Jeong JJ, Park H, Park BH, Mannaa M, Sang MK, Choi IG, Kim KD. Draft Genome Sequence of a Biocontrol Rhizobacterium, Chryseobacterium kwangjuense Strain KJ1R5, Isolated from Pepper (Capsicum annuum). GENOME ANNOUNCEMENTS 2016; 4:e00301-16. [PMID: 27103726 PMCID: PMC4841141 DOI: 10.1128/genomea.00301-16] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Accepted: 03/02/2016] [Indexed: 12/04/2022]
Abstract
Strain KJ1R5 of the rhizobacterium ITALIC! Chryseobacterium kwangjuenseis an effective biocontrol agent against Phytophthora blight of pepper caused by a destructive soilborne oomycete, ITALIC! Phytophthora capsici Here, we present the draft genome sequence of strain KJ1R5, which contains genes related to biocontrol, plant growth promotion, and environmental stress adaptation.
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Affiliation(s)
- Jin-Ju Jeong
- Laboratory of Plant Disease and Biocontrol, College of Life Sciences and Biotechnology, Korea University, Seoul, Republic of Korea
| | - Hongjae Park
- Department of Biotechnology, Korea University, Seoul, Republic of Korea
| | - Byeong Hyeok Park
- Department of Biotechnology, Korea University, Seoul, Republic of Korea
| | - Mohamed Mannaa
- Laboratory of Plant Disease and Biocontrol, College of Life Sciences and Biotechnology, Korea University, Seoul, Republic of Korea
| | - Mee Kyung Sang
- Laboratory of Plant Disease and Biocontrol, College of Life Sciences and Biotechnology, Korea University, Seoul, Republic of Korea Division of Agricultural Microbiology, National Academy of Agricultural Science, Rural Development Administration, Jeonju, Republic of Korea
| | - In-Geol Choi
- Department of Biotechnology, Korea University, Seoul, Republic of Korea
| | - Ki Deok Kim
- Laboratory of Plant Disease and Biocontrol, College of Life Sciences and Biotechnology, Korea University, Seoul, Republic of Korea
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124
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Zhang HX, Jin JH, He YM, Lu BY, Li DW, Chai WG, Khan A, Gong ZH. Genome-Wide Identification and Analysis of the SBP-Box Family Genes under Phytophthora capsici Stress in Pepper (Capsicum annuum L.). FRONTIERS IN PLANT SCIENCE 2016; 7:504. [PMID: 27148327 PMCID: PMC4832253 DOI: 10.3389/fpls.2016.00504] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Accepted: 03/29/2016] [Indexed: 05/05/2023]
Abstract
SQUAMOSA promoter binding protein (SBP)-box genes encode plant-specific transcription factors that are extensively involved in many physiological and biochemical processes, including growth, development, and signal transduction. However, pepper (Capsicum annuum L.) SBP-box family genes have not been well characterized. We investigated SBP-box family genes in the pepper genome and characterized these genes across both compatible and incompatible strain of Phytophthora capsici, and also under different hormone treatments. The results indicated that total 15 members were identified and distributed on seven chromosomes of pepper. Phylogenetic analysis showed that SBP-box genes of pepper can be classified into six groups. In addition, duplication analysis within pepper genome, as well as between pepper and Arabidopsis genomes demonstrated that there are four pairs of homology of SBP-box genes in the pepper genome and 10 pairs between pepper and Arabidopsis genomes. Tissue-specific expression analysis of the CaSBP genes demonstrated their diverse spatiotemporal expression patterns. The expression profiles were similarly analyzed following exposure to P. capsici inoculation and hormone treatments. It was shown that nine of the CaSBP genes (CaSBP01, 02, 03, 04, 05, 06, 11, 12, and 13) exhibited a dramatic up-regulation after compatible HX-9 strain (P. capsici) inoculation, while CaSBP09 and CaSBP15 were down-regulated. In case of PC strain (P. capsici) infection six of the CaSBP genes (CaSBP02, 05, 06, 11, 12, and 13) were arose while CaSBP14 was down regulated. Furthermore, Salicylic acid, Methyl jasmonate and their biosynthesis inhibitors treatment indicated that some of the CaSBP genes are potentially involved in these hormone regulation pathways. This genome-wide identification, as well as characterization of evolutionary relationships and expression profiles of the pepper CaSBP genes, will help to improve pepper stress tolerance in the future.
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Affiliation(s)
- Huai-Xia Zhang
- College of Horticulture, Northwest A&F UniversityYangling, China
| | - Jing-Hao Jin
- College of Horticulture, Northwest A&F UniversityYangling, China
| | - Yu-Mei He
- College of Horticulture, Northwest A&F UniversityYangling, China
| | - Bo-Ya Lu
- College of Horticulture, Northwest A&F UniversityYangling, China
| | - Da-Wei Li
- College of Horticulture, Northwest A&F UniversityYangling, China
| | - Wei-Guo Chai
- Institute of Vegetables, Hangzhou Academy of Agricultural SciencesHangzhou, China
| | - Abid Khan
- College of Horticulture, Northwest A&F UniversityYangling, China
| | - Zhen-Hui Gong
- College of Horticulture, Northwest A&F UniversityYangling, China
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125
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Pang Z, Chen L, Mu W, Liu L, Liu X. Insights into the adaptive response of the plant-pathogenic oomycete Phytophthora capsici to the fungicide flumorph. Sci Rep 2016; 6:24103. [PMID: 27050922 PMCID: PMC4822174 DOI: 10.1038/srep24103] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Accepted: 03/21/2016] [Indexed: 01/11/2023] Open
Abstract
Phytophthora capsici is an important oomycete plant pathogen that causes significant losses worldwide. The carboxylic acid amide fungicide flumorph has shown excellent activity against oomycete plant pathogens. Despite its potential, there remains concern that the sexual reproduction of oomycete pathogens, which results in genetic recombination, could result in the rapid development of resistance to flumorph. The current study utilized an iTRAQ (isobaric tags for relative and absolute quantitation) based method to compare differences between the proteome of the parental P. capsici isolate PCAS1 and its sexual progeny S2-838, which exhibits significant resistance to flumorph. A total of 2396 individual proteins were identified, of these, 181 were considered to be associated with the adaptive response of P. capsici to flumorph. The subsequent bioinformatic analysis revealed that the adaptive response of P. capsici to flumorph was complex and regulated by multiple mechanisms, including utilising carbohydrate from the host environment to compensate for the cell wall stress induced by flumorph, a shift in energy generation, decreased amino acids biosynthesis, and elevated levels of proteins associated with the pathogen's response to stimulus and transmembrane transport. Moreover, the results of the study provided crucial data that could provide the basis for early monitoring of flumorph resistance in field populations of P. capsici.
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Affiliation(s)
- Zhili Pang
- Department of Plant Pathology, College of Agriculture and Biotechnology, China Agricultural University, Beijing, P. R. China
| | - Lei Chen
- Department of Plant Pathology, College of Agriculture and Biotechnology, China Agricultural University, Beijing, P. R. China
- College of Forestry, Beijing Forestry University, Beijing, P. R. China
| | - Wenjun Mu
- Department of Plant Pathology, College of Agriculture and Biotechnology, China Agricultural University, Beijing, P. R. China
- Zhengzhou Tobacco Research Institute of CNTC, P. R. China
| | - Li Liu
- Department of Plant Pathology, College of Agriculture and Biotechnology, China Agricultural University, Beijing, P. R. China
| | - Xili Liu
- Department of Plant Pathology, College of Agriculture and Biotechnology, China Agricultural University, Beijing, P. R. China
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126
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Quesada-Ocampo LM, Vargas AM, Naegele RP, Francis DM, Hausbeck MK. Resistance to Crown and Root Rot Caused by Phytophthora capsici in a Tomato Advanced Backcross of Solanum habrochaites and Solanum lycopersicum. PLANT DISEASE 2016; 100:829-835. [PMID: 30688608 DOI: 10.1094/pdis-08-15-0888-re] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Phytophthora capsici causes devastating disease on many vegetable crops, including tomato and other solanaceous species. Solanum habrochaites accession LA407, a wild relative of cultivated tomato, has shown complete resistance to four P. capsici isolates from Michigan cucurbitaceous and solanaceous crops in a previous study. Greenhouse experiments were conducted to evaluate 62 lines of a tomato inbred backcross population between LA407 and the cultivated tomato 'Hunt 100' and 'Peto 95-43' for resistance to two highly virulent P. capsici isolates. Roots of 6-week-old seedlings were inoculated with each of two P. capsici isolates and maintained in the greenhouse. Plants were evaluated for wilting and plant death three times per week for 5 weeks. Significant differences were observed in disease response among the inbred tomato lines. Most lines evaluated were susceptible to P. capsici isolate 12889 but resistant to isolate OP97; 24 tomato lines were resistant to both isolates. Heritability of Phytophthora root rot resistance was high in this population. Polymorphic molecular markers located in genes related to resistance and defense responses were identified and added to a genetic map previously generated for the population. Resistant lines and polymorphic markers identified in this study are a valuable resource for development of tomato varieties resistant to P. capsici.
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Affiliation(s)
- L M Quesada-Ocampo
- Department of Plant Pathology, North Carolina State University, Raleigh 27695
| | - A M Vargas
- Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing 48824
| | - R P Naegele
- Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing 48824
| | - D M Francis
- Department of Horticulture and Crop Science, Ohio Agricultural Research and Development Center, Wooster 44691
| | - M K Hausbeck
- Department of Plant, Soil and Microbial Sciences, Michigan State University
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127
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Xu X, Chao J, Cheng X, Wang R, Sun B, Wang H, Luo S, Xu X, Wu T, Li Y. Mapping of a Novel Race Specific Resistance Gene to Phytophthora Root Rot of Pepper (Capsicum annuum) Using Bulked Segregant Analysis Combined with Specific Length Amplified Fragment Sequencing Strategy. PLoS One 2016; 11:e0151401. [PMID: 26992080 PMCID: PMC4798474 DOI: 10.1371/journal.pone.0151401] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Accepted: 02/26/2016] [Indexed: 11/19/2022] Open
Abstract
Phytophthora root rot caused by Phytophthora capsici (P. capsici) is a serious limitation to pepper production in Southern China, with high temperature and humidity. Mapping PRR resistance genes can provide linked DNA markers for breeding PRR resistant varieties by molecular marker-assisted selection (MAS). Two BC1 populations and an F2 population derived from a cross between P. capsici-resistant accession, Criollo de Morelos 334 (CM334) and P. capsici-susceptible accession, New Mexico Capsicum Accession 10399 (NMCA10399) were used to investigate the genetic characteristics of PRR resistance. PRR resistance to isolate Byl4 (race 3) was controlled by a single dominant gene, PhR10, that was mapped to an interval of 16.39Mb at the end of the long arm of chromosome 10. Integration of bulked segregant analysis (BSA) and Specific Length Amplified Fragment sequencing (SLAF-seq) provided an efficient genetic mapping strategy. Ten polymorphic Simple Sequence Repeat (SSR) markers were found within this region and used to screen the genotypes of 636 BC1 plants, delimiting PhR10 to a 2.57 Mb interval between markers P52-11-21 (1.5 cM away) and P52-11-41 (1.1 cM). A total of 163 genes were annotated within this region and 31 were predicted to be associated with disease resistance. PhR10 is a novel race specific gene for PRR, and this paper describes linked SSR markers suitable for marker-assisted selection of PRR resistant varieties, also laying a foundation for cloning the resistance gene.
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Affiliation(s)
- Xiaomei Xu
- Vegetable Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, China
- Guangdong Key Lab for New Technology Research of Vegetables, Guangzhou, China
| | - Juan Chao
- Vegetable Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, China
- Guangdong Key Lab for New Technology Research of Vegetables, Guangzhou, China
| | - Xueli Cheng
- Vegetable Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, China
- Guangdong Key Lab for New Technology Research of Vegetables, Guangzhou, China
| | - Rui Wang
- Vegetable Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, China
- Guangdong Key Lab for New Technology Research of Vegetables, Guangzhou, China
| | - Baojuan Sun
- Vegetable Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, China
- Guangdong Key Lab for New Technology Research of Vegetables, Guangzhou, China
| | - Hengming Wang
- Vegetable Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, China
| | - Shaobo Luo
- Vegetable Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, China
- Guangdong Key Lab for New Technology Research of Vegetables, Guangzhou, China
| | - Xiaowan Xu
- Vegetable Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, China
| | - Tingquan Wu
- Vegetable Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, China
- Guangdong Key Lab for New Technology Research of Vegetables, Guangzhou, China
| | - Ying Li
- Vegetable Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, China
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128
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Islam S, Akanda AM, Prova A, Islam MT, Hossain MM. Isolation and Identification of Plant Growth Promoting Rhizobacteria from Cucumber Rhizosphere and Their Effect on Plant Growth Promotion and Disease Suppression. Front Microbiol 2016; 6:1360. [PMID: 26869996 PMCID: PMC4735380 DOI: 10.3389/fmicb.2015.01360] [Citation(s) in RCA: 126] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2015] [Accepted: 11/16/2015] [Indexed: 01/31/2023] Open
Abstract
Plant growth promoting rhizobacteria (PGPR) are the rhizosphere bacteria that may be utilized to augment plant growth and suppress plant diseases. The objectives of this study were to identify and characterize PGPR indigenous to cucumber rhizosphere in Bangladesh, and to evaluate their ability to suppress Phytophthora crown rot in cucumber. A total of 66 isolates were isolated, out of which 10 (PPB1, PPB2, PPB3, PPB4, PPB5, PPB8, PPB9, PPB10, PPB11, and PPB12) were selected based on their in vitro plant growth promoting attributes and antagonism of phytopathogens. Phylogenetic analysis of 16S rRNA sequences identified these isolates as new strains of Pseudomonas stutzeri, Bacillus subtilis, Stenotrophomonas maltophilia, and Bacillus amyloliquefaciens. The selected isolates produced high levels (26.78-51.28 μg mL(-1)) of indole-3-acetic acid, while significant acetylene reduction activities (1.79-4.9 μmole C2H4 mg(-1) protein h(-1)) were observed in eight isolates. Cucumber plants grown from seeds that were treated with these PGPR strains displayed significantly higher levels of germination, seedling vigour, growth, and N content in root and shoot tissue compared to non-treated control plants. All selected isolates were able to successfully colonize the cucumber roots. Moreover, treating cucumber seeds with these isolates significantly suppressed Phytophthora crown rot caused by Phytophthora capsici, and characteristic morphological alterations in P. capsici hyphae that grew toward PGPR colonies were observed. Since these PGPR inoculants exhibited multiple traits beneficial to the host plants, they may be applied in the development of new, safe, and effective seed treatments as an alternative to chemical fungicides.
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Affiliation(s)
- Shaikhul Islam
- Department of Plant Pathology, EXIM Bank Agricultural UniversityChapainawabganj, Bangladesh
| | - Abdul M. Akanda
- Department of Plant Pathology, EXIM Bank Agricultural UniversityChapainawabganj, Bangladesh
| | - Ananya Prova
- Department of Plant Pathology, EXIM Bank Agricultural UniversityChapainawabganj, Bangladesh
| | - Md. T. Islam
- Department of Biotechnology, Bangabandhu Sheikh Mujibur Rahman Agricultural UniversityGazipur, Bangladesh
| | - Md. M. Hossain
- Department of Plant Pathology, Bangabandhu Sheikh Mujibur Rahman Agricultural UniversityGazipur, Bangladesh
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129
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Amini J, Farhang V, Javadi T, Nazemi J. Antifungal Effect of Plant Essential Oils on Controlling Phytophthora Species. THE PLANT PATHOLOGY JOURNAL 2016; 32:16-24. [PMID: 26889111 PMCID: PMC4755671 DOI: 10.5423/ppj.oa.05.2015.0091] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Revised: 09/20/2015] [Accepted: 09/23/2015] [Indexed: 05/20/2023]
Abstract
In this study, antifungal activity of essential oils of Cymbopogon citratus and Ocimum basilicum and two fungicides Mancozeb and Metalaxyl-Mancozeb in six different concentrations were investigated for controlling three species of Phytophthora, including P. capsici, P. drechsleri and P. melonis on pepper, cucumber and melon under in vitro and greenhouse conditions, respectively. Under the in vitro condition, the median effective concen- tration (EC50) values (ppm) of plant essential oils and fungicides were measured. In greenhouse, soil infested with Phytophthora species was treated by adding 50 ml of essential oils and fungicides (100 ppm). Disease severity was determined after 28 days. Among two tested plant essential oils, C. citratus had the lowest EC50 values for inhibition of the mycelial growth of P. capsici (31.473), P. melonis (33.097) and P. drechsleri (69.112), respectively. The mean EC50 values for Metalaxyl-Mancozeb on these pathogens were 20.87, 20.06 and 17.70, respectively. Chemical analysis of plant essential oils by GC-MS showed that, among 42 compounds identified from C. citratus, two compounds β-geranial (α-citral) (39.16%) and z-citral (30.95%) were the most abundant. Under the greenhouse condition, Metalaxyl-Mancozeb caused the greatest reduction in disease severity, 84.2%, 86.8% and 92.1% on melon, cucumber, and pepper, respectively. The C. citratus essential oil reduced disease severity from 47.4% to 60.5% compared to the untreated control (p≤0.05). Essential oils of O. basilicum had the lowest effects on the pathogens under in vitro and greenhouse conditions. These results show that essential oils may contribute to the development of new antifungal agents to protect the crops from Phytophthora diseases.
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Affiliation(s)
- Jahanshir Amini
- Department of Plant Protection, Agriculture Faculty, University of Kurdistan, P. O. Box 416, Sanandaj,
Iran
| | - Vahid Farhang
- Department of Plant Protection, Agriculture Faculty, University of Kurdistan, P. O. Box 416, Sanandaj,
Iran
| | - Taimoor Javadi
- Department of Horticulture, Agriculture Faculty, University of Kurdistan, Sanandaj,
Iran
| | - Javad Nazemi
- Department of Plant Protection, Agriculture Faculty, University of Kurdistan, P. O. Box 416, Sanandaj,
Iran
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130
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Castro-Rocha A, Shrestha S, Lyon B, Grimaldo-Pantoja GL, Flores-Marges JP, Valero-Galván J, Aguirre-Ramírez M, Osuna-Ávila P, Gómez-Dorantes N, Ávila-Quezada G, de Jesús Luna-Ruíz J, Rodríguez-Alvarado G, Fernández-Pavía SP, Lamour K. An initial assessment of genetic diversity for Phytophthora capsici in northern and central Mexico. Mycol Prog 2016. [DOI: 10.1007/s11557-016-1157-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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131
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Jin JH, Zhang HX, Tan JY, Yan MJ, Li DW, Khan A, Gong ZH. A New Ethylene-Responsive Factor CaPTI1 Gene of Pepper (Capsicum annuum L.) Involved in the Regulation of Defense Response to Phytophthora capsici. FRONTIERS IN PLANT SCIENCE 2016; 6:1217. [PMID: 26779241 PMCID: PMC4705296 DOI: 10.3389/fpls.2015.01217] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Accepted: 12/17/2015] [Indexed: 05/18/2023]
Abstract
Ethylene-responsive factors (ERF) are usually considered to play diverse roles in plant response to biotic and abiotic stresses. In this study, an ERF gene CaPTI1 was isolated from pepper transcriptome database. CaPTI1 contains an open reading frame (ORF) of 543 bp, which encodes a putative polypeptide of 180 amino acids with a theoretical molecular weight of 20.30 kDa. Results of expression profile showed that CaPTI1 had a highest expression level in roots and this gene could not only response to the infection of Phytophthora capsici and the stresses of cold and drought, but also be induced by the signaling molecule (salicylic acid, Methyl Jasmonate, Ethephon, and hydogen peroxide). Furthermore, virus-induce gene silencing (VIGS) of CaPTI1 in pepper weakened the defense response significantly by reducing the expression of defense related genes CaPR1, CaDEF1 and CaSAR82 and also the root activity. These results suggested that CaPTI1 is involved in the regulation of defense response to P. capsici in pepper.
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Affiliation(s)
| | | | | | | | | | | | - Zhen-Hui Gong
- College of Horticulture, Northwest A&F UniversityYangling, China
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132
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Zohara F, Akanda MAM, Paul NC, Rahman M, Islam MT. Inhibitory effects of Pseudomonas spp. on plant pathogen Phytophthora capsici in vitro and in planta. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2016. [DOI: 10.1016/j.bcab.2015.12.009] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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133
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Enzenbacher TB, Naegele RP, Hausbeck MK. Susceptibility of Greenhouse Ornamentals to Phytophthora capsici and P. tropicalis. PLANT DISEASE 2015; 99:1808-1815. [PMID: 30699517 DOI: 10.1094/pdis-03-15-0333-re] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The susceptibility of fabaceous (Lupinus and Lathyrus spp.) and solanaceous (Calibrachoa, Browallia, Nicotiana, Nierembergia, and Petunia spp.) ornamental plants compared with straightneck squash (Cucurbita pepo) inoculated with Phytophthora capsici and P. tropicalis was investigated in greenhouse studies. Four P. capsici isolates and one P. tropicalis isolate were evaluated. Flowering tobacco (Nicotiana × sanderae), sweet pea (Lathyrus latifolius), lupine (Lupinus polyphyllus), squash, and million bells (Calibrachoa × hybrida) were susceptible to P. capsici and P. tropicalis. Bush violet (Browallia speciosa) and cup flower (Nierembergia scoparia) were not susceptible to either pathogen. Petunia (Petunia × hybrida) was susceptible to P. capsici but not P. tropicalis. Area under the plant growth curve (AUPGC) was also affected in some susceptible plants. AUPGC was significantly different in inoculated plants compared with the untreated controls of Nicotiana and Calibrachoa. In addition, six Calibrachoa cultivars were evaluated for susceptibility to P. capsici and P. tropicalis in a separate experiment. Although all Calibrachoa cultivars were susceptible to P. capsici and P. tropicalis, 'Celebration Purple Star' displayed limited disease following inoculation with either pathogen. Calibrachoa 'Cabaret' and 'Can-Can' inoculated with P. capsici or P. tropicalis displayed significant differences in AUPGC compared with the uninoculated controls. 'Callie', 'Million Bells Cherry Pink', and 'Superbells' had significantly reduced AUPGC compared with the controls when inoculated with P. tropicalis but not P. capsici. These results expand the host range of P. capsici to include Calibrachoa spp., L. polyphyllus, and Lathyrus latifolius, and P. tropicalis to include L. latifolius, Nicotiana spp., and straightneck squash.
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Affiliation(s)
- T B Enzenbacher
- Department of Plant, Soil, and Microbial Sciences, Michigan State University, East Lansing 48824
| | - R P Naegele
- Department of Plant, Soil, and Microbial Sciences, Michigan State University, East Lansing 48824
| | - M K Hausbeck
- Department of Plant, Soil, and Microbial Sciences, Michigan State University, East Lansing 48824
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134
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Krasnow CS, Hausbeck MK. Pathogenicity of Phytophthora capsici to Brassica Vegetable Crops and Biofumigation Cover Crops (Brassica spp.). PLANT DISEASE 2015; 99:1721-1726. [PMID: 30699519 DOI: 10.1094/pdis-03-15-0271-re] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The soilborne oomycete Phytophthora capsici causes root, crown, and fruit rot of many vegetable crops in the Cucurbitaceae and Solanaceae families. P. capsici is a persistent problem in vegetable fields due to long-lived oospores that survive in soil and resist weathering and degradation. Vegetable crops in the Brassicaceae family have been considered nonhosts of P. capsici and are planted as rotational crops in infested fields. Brassica spp. are also grown as biofumigation cover crops to reduce inoculum levels of P. capsici and other soilborne pathogens, and this use has increased concurrent with restrictions on soil fumigation. Oriental mustard (Brassica juncea), oilseed rape (B. napus), and oilseed radish (Raphanus sativus var. oleiferus) contain high levels of glucosinolates and are widely recommended for biofumigation and as cover crops. The objective of this study was to evaluate vegetables and biofumigation cover crops in the Brassicaceae family for susceptibility to P. capsici. Brassica spp. used as vegetable crops and for biofumigation were grown in P. capsici-infested potting soil in the greenhouse and disease incidence and severity were recorded. In greenhouse trials, infection by the pathogen reduced the fresh weight of all Brassica spp. tested and resulted in plant death of 44% of plants of B. juncea 'Pacific Gold'. P. capsici isolates exhibited differences in virulence (P < 0.0001), and were reisolated from the roots of all Brassica spp. included in the study. The biofumigation cover crop Pacific Gold mustard may not reduce populations of P. capsici in soil and, instead, may sustain or increase pathogen levels. Further research is necessary to test this possibility under field conditions.
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Affiliation(s)
- Charles S Krasnow
- Department of Plant, Soil, and Microbial Sciences, Michigan State University, East Lansing, 48824
| | - Mary K Hausbeck
- Department of Plant, Soil, and Microbial Sciences, Michigan State University, East Lansing, 48824
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135
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Ando K, Carr KM, Colle M, Mansfeld BN, Grumet R. Exocarp Properties and Transcriptomic Analysis of Cucumber (Cucumis sativus) Fruit Expressing Age-Related Resistance to Phytophthora capsici. PLoS One 2015; 10:e0142133. [PMID: 26528543 PMCID: PMC4631441 DOI: 10.1371/journal.pone.0142133] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Accepted: 10/16/2015] [Indexed: 12/03/2022] Open
Abstract
Very young cucumber (Cucumis sativus) fruit are highly susceptible to infection by the oomycete pathogen, Phytophthora capsici. As the fruit complete exponential growth, at approximately 10-12 days post pollination (dpp), they transition to resistance. The development of age-related resistance (ARR) is increasingly recognized as an important defense against pathogens, however, underlying mechanisms are largely unknown. Peel sections from cucumber fruit harvested at 8 dpp (susceptible) and 16 dpp (resistant) showed equivalent responses to inoculation as did whole fruit, indicating that the fruit surface plays an important role in defense against P. capsici. Exocarp from 16 dpp fruit had thicker cuticles, and methanolic extracts of peel tissue inhibited growth of P. capsici in vitro, suggesting physical or chemical components to the ARR. Transcripts specifically expressed in the peel vs. pericarp showed functional differentiation. Transcripts predominantly expressed in the peel were consistent with fruit surface associated functions including photosynthesis, cuticle production, response to the environment, and defense. Peel-specific transcripts that exhibited increased expression in 16 dpp fruit relative to 8 dpp fruit, were highly enriched (P<0.0001) for response to stress, signal transduction, and extracellular and transport functions. Specific transcripts included genes associated with potential physical barriers (i.e., cuticle), chemical defenses (flavonoid biosynthesis), oxidative stress, penetration defense, and molecular pattern (MAMP)-triggered or effector-triggered (R-gene mediated) pathways. The developmentally regulated changes in gene expression between peels from susceptible- and resistant- age fruits suggest programming for increased defense as the organ reaches full size.
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Affiliation(s)
- Kaori Ando
- Program in Plant Breeding, Genetics and Biotechnology, Michigan State University, East Lansing, MI, 48824, United States of America
| | - Kevin M. Carr
- Research Technology Support Facility, Michigan State University, East Lansing, MI, United States of America
| | - Marivi Colle
- Program in Plant Breeding, Genetics and Biotechnology, Michigan State University, East Lansing, MI, 48824, United States of America
| | - Ben N. Mansfeld
- Program in Plant Breeding, Genetics and Biotechnology, Michigan State University, East Lansing, MI, 48824, United States of America
| | - Rebecca Grumet
- Program in Plant Breeding, Genetics and Biotechnology, Michigan State University, East Lansing, MI, 48824, United States of America
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136
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Jiang L, Wang H, Xu H, Qiao K, Xia X, Wang K. Transportation behaviour of fluopicolide and its control effect against Phytophthora capsici in greenhouse tomatoes after soil application. PEST MANAGEMENT SCIENCE 2015; 71:1008-1014. [PMID: 25132333 DOI: 10.1002/ps.3879] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2014] [Revised: 07/14/2014] [Accepted: 08/07/2014] [Indexed: 06/03/2023]
Abstract
BACKGROUND Fluopicolide, a novel benzamide fungicide, was registered for control of oomycete pathogens, including Phytophthora capsici. In this study, fluopicolide (5% SC) was applied in soil at rates of 1.5, 3 and 6 L ha(-1) [the normal (ND), double (DD) and quadruple dosages (QD) respectively] to investigate its transportation behaviour and control efficiency on tomato blight as a soil treatment agent. RESULTS The results showed that fluopicolide applied to soil could be absorbed by tomato roots and then transplanted to stems and leaves. It could exist in tomato roots for more than 30 days, and in leaves and stems until day 20 after application. The decline in fluopicolide in soil was in accordance with a first-order dynamics equation, with half-lives of 5.33, 4.75 and 5.42 days for the ND, DD and QD treatments respectively. The control efficiencies of fluopicolide were better with soil application than with spraying application, and the inhibition ratios were 93.02, 97.67 and 100 on day 21 for the ND, DD and QD treatments respectively. CONCLUSION Soil application of fluopicolide could control P. capsici in greenhouse tomatoes with high efficiency and long persistence.
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Affiliation(s)
- Lili Jiang
- Department of Plant Protection, Shandong Agricultural University, Tai'an, Shandong, China
| | - Hongyan Wang
- Cotton Research Centre, Shandong Academy of Agricultural Sciences, Ji'nan, Shandong, China
| | - Hui Xu
- Shandong United Pesticide Industry Co. Ltd, Ji'nan, Shandong, China
| | - Kang Qiao
- Department of Plant Protection, Shandong Agricultural University, Tai'an, Shandong, China
| | - Xiaoming Xia
- Department of Plant Protection, Shandong Agricultural University, Tai'an, Shandong, China
| | - Kaiyun Wang
- Department of Plant Protection, Shandong Agricultural University, Tai'an, Shandong, China
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137
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Pang Z, Chen L, Miao J, Wang Z, Bulone V, Liu X. Proteomic profile of the plant-pathogenic oomycete Phytophthora capsici
in response to the fungicide pyrimorph. Proteomics 2015; 15:2972-82. [DOI: 10.1002/pmic.201400502] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2014] [Revised: 03/01/2015] [Accepted: 04/21/2015] [Indexed: 11/10/2022]
Affiliation(s)
- Zhili Pang
- Department of Plant Pathology; College of Agriculture and Biotechnology, China Agricultural University; Beijing P. R. China
- Division of Glycoscience; Royal Institute of Technology (KTH), AlbaNova University Centre; Stockholm Sweden
| | - Lei Chen
- Department of Plant Pathology; College of Agriculture and Biotechnology, China Agricultural University; Beijing P. R. China
- College of Forestry; Beijing Forestry University; Beijing P. R. China
| | - Jianqiang Miao
- Department of Plant Pathology; College of Agriculture and Biotechnology, China Agricultural University; Beijing P. R. China
| | - Zhiwen Wang
- Department of Plant Pathology; College of Agriculture and Biotechnology, China Agricultural University; Beijing P. R. China
| | - Vincent Bulone
- Division of Glycoscience; Royal Institute of Technology (KTH), AlbaNova University Centre; Stockholm Sweden
- Australian Research Council Centre of Excellence in Plant Cell Walls; School of Agriculture, Food and Wine, University of Adelaide; Waite Campus Glen Osmond South Australia Australia
| | - Xili Liu
- Department of Plant Pathology; College of Agriculture and Biotechnology, China Agricultural University; Beijing P. R. China
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138
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Kamoun S, Furzer O, Jones JDG, Judelson HS, Ali GS, Dalio RJD, Roy SG, Schena L, Zambounis A, Panabières F, Cahill D, Ruocco M, Figueiredo A, Chen XR, Hulvey J, Stam R, Lamour K, Gijzen M, Tyler BM, Grünwald NJ, Mukhtar MS, Tomé DFA, Tör M, Van Den Ackerveken G, McDowell J, Daayf F, Fry WE, Lindqvist-Kreuze H, Meijer HJG, Petre B, Ristaino J, Yoshida K, Birch PRJ, Govers F. The Top 10 oomycete pathogens in molecular plant pathology. MOLECULAR PLANT PATHOLOGY 2015; 16:413-34. [PMID: 25178392 PMCID: PMC6638381 DOI: 10.1111/mpp.12190] [Citation(s) in RCA: 474] [Impact Index Per Article: 52.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Oomycetes form a deep lineage of eukaryotic organisms that includes a large number of plant pathogens which threaten natural and managed ecosystems. We undertook a survey to query the community for their ranking of plant-pathogenic oomycete species based on scientific and economic importance. In total, we received 263 votes from 62 scientists in 15 countries for a total of 33 species. The Top 10 species and their ranking are: (1) Phytophthora infestans; (2, tied) Hyaloperonospora arabidopsidis; (2, tied) Phytophthora ramorum; (4) Phytophthora sojae; (5) Phytophthora capsici; (6) Plasmopara viticola; (7) Phytophthora cinnamomi; (8, tied) Phytophthora parasitica; (8, tied) Pythium ultimum; and (10) Albugo candida. This article provides an introduction to these 10 taxa and a snapshot of current research. We hope that the list will serve as a benchmark for future trends in oomycete research.
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Affiliation(s)
- Sophien Kamoun
- The Sainsbury Laboratory, Norwich Research Park, Norwich, NR4 7UH, UK
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139
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Boiteux J, Soto Vargas C, Pizzuolo P, Lucero G, Silva MF. Phenolic characterization and antimicrobial activity of folk medicinal plant extracts for their applications in olive production. Electrophoresis 2015; 35:1709-18. [PMID: 24668423 DOI: 10.1002/elps.201300562] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2013] [Revised: 02/25/2014] [Accepted: 03/19/2014] [Indexed: 12/12/2022]
Abstract
Phytophthora spp is important in plant pathology due to the importance of the diseases it causes. In olive trees, severe damages are caused by the disease known as "dry branch" occasioned by Phytophthora nicotianae, P. citrophthora and P. palmivora. Much effort has been made to find efficient methods of control, with a low negative impact on environment. In this regard, treatment with plant extracts is a valid strategy. The aims of the present study are (i) to determine the polyphenol composition of extracts of Thymus vulgaris, Origanum vulgare, Matricaria recutita, and Larrea divaricata by CZE, (ii) correlate the analytical composition of these extracts with the inhibition on the mycelial growth, and (iii) determine the individual antimicrobial activity of the most active ingredients. A simple methodology was developed for the determination of catechin, naringenin, cinnamic acid, syringic acid, chlorogenic acid, apigenin, vanillic acid, luteolin, quercetin, and caffeic acid in plant extracts by CZE. The extraction of phenolic compounds in extract was performed by a miniaturized solid phase extraction using a home-made minicolumn packed with suitable filtering material (C18 , 50 mg). The optimized analyses conditions were: 30 mM boric acid buffer, pH 9.50; capillary, 57 cm full length, 50 cm effective length, 75 μm id, hydrodynamic injection 30 mbar, 2 s; 25 kV; 25°C, detection by UV absorbance at 290 nm. Sample results suggest that phenolic composition seems to have a great influence on inhibition of pathogens. The highest inhibitions of mycelial growth were observed for cinnamic acid and naringenin.
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Affiliation(s)
- Joana Boiteux
- Instituto de Biología Agrícola de Mendoza (IBAM-CONICET), Facultad de Ciencias Agrarias, Universidad Nacional de Cuyo, Mendoza, Argentina
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140
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Yang CH, Lin MJ, Su HJ, Ko WH. Multiple resistance-activating substances produced by Humicola phialophoroides isolated from soil for control of Phytophthora blight of pepper. BOTANICAL STUDIES 2014; 55:40. [PMID: 28510968 PMCID: PMC5432772 DOI: 10.1186/1999-3110-55-40] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2012] [Accepted: 03/03/2014] [Indexed: 06/01/2023]
Abstract
BACKGROUND Microorganisms capable of utilizing vegetable tissues for multiplication in soil were isolated, cultivated in liquid medium prepared from the same vegetable tissues, and tested for ability to activate resistance in pepper leaves against Phytophthora blight caused by Phytophthora capsici. RESULTS Among the 121 microorganisms isolated, a fungus Humicola phialophoroides showed distinct ability to produce substances capable of activating resistance. The resistance-activating substances produced by H. phialophoroides were mostly retained in the mycelium, and were readily extracted from the mycelium powder with polar solvents. The extract was not inhibitory to zoospore germination or germ tube growth of P. capsici. In pepper leaves, the extract took only about 12 h to activate resistance against P. capsici. After activation, washing treated leaf surface with water did not have much effect on the resistance expression. In addition to being able to move from the upper leaf surface to lower leaf surface, the resistance-activating substances were capable of moving 5 mm acropetally and 10 mm basipetally in pepper leaves, Chromatography of the extract on silica gel column suggests that there are probably more than three components in the extract with resistance-activating ability. The resistance-activating activity of the mycelium extract was not affected by treatment with either cation or anion exchange resins, indicating that none of the active components have positive or negative charges on their molecules. CONCLUSION Results show that H. phialophoroides is capable of producing multiple resistance-activating substances which are mostly retained in the mycelium. The study also indicates that none of the active components have positive or negative charges on their molecules.
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Affiliation(s)
- Ching-Hui Yang
- Department of Plant Pathology, National Chung Hsing University, Taichung, Taiwan
| | - Mei-Ju Lin
- Department of Plant Pathology, National Chung Hsing University, Taichung, Taiwan
| | - Huey-Jen Su
- Department of Nursing, Meiho University, Neipu, Pingtung Taiwan
| | - Wen-Hsiung Ko
- Department of Plant Pathology, National Chung Hsing University, Taichung, Taiwan
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141
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Vega-Arreguín JC, Jalloh A, Bos JI, Moffett P. Recognition of an Avr3a homologue plays a major role in mediating nonhost resistance to Phytophthora capsici in Nicotiana species. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2014; 27:770-80. [PMID: 24725207 DOI: 10.1094/mpmi-01-14-0014-r] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Nonhost resistance is a commonly occurring phenomenon wherein all accessions or cultivars of a plant species are resistant to all strains of a pathogen species and is likely the manifestation of multiple molecular mechanisms. Phytophthora capsici is a soil-borne oomycete that causes Phytophthora blight disease in many solanaceous and cucurbitaceous plants worldwide. Interest in P. capsici has increased considerably with the sequencing of its genome and its increasing occurrence in multiple crops. However, molecular interactions between P. capsici and both its hosts and its nonhosts are poorly defined. We show here that tobacco (Nicotiana tabacum) acts like a nonhost for P. capsici and responds to P. capsici infection with a hypersensitive response (HR). Furthermore, we have found that a P. capsici Avr3a-like gene (PcAvr3a1) encoding a putative RXLR effector protein produces a HR upon transient expression in tobacco and several other Nicotiana species. This HR response correlated with resistance in 19 of 23 Nicotiana species and accessions tested, and knock-down of PcAvr3a1 expression by host-induced gene silencing allowed infection of resistant tobacco. Our results suggest that many Nicotiana species have the capacity to recognize PcAvr3a1 via the products of endogenous disease resistance (R) genes and that this R gene-mediated response is a major component of nonhost resistance to P. capsici.
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142
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Naegele RP, Ashrafi H, Hill TA, Chin-Wo SR, Van Deynze AE, Hausbeck MK. QTL mapping of fruit rot resistance to the plant pathogen Phytophthora capsici in a recombinant inbred line Capsicum annuum population. PHYTOPATHOLOGY 2014; 104:479-483. [PMID: 24168044 DOI: 10.1094/phyto-05-13-0143-r] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Phytophthora capsici is an important pepper (Capsicum annuum) pathogen causing fruit and root rot, and foliar blight in field and greenhouse production. Previously, an F6 recombinant inbred line population was evaluated for fruit rot susceptibility. Continuous variation among lines and partial and isolate-specific resistance were found. In this study, Phytophthora fruit rot resistance was mapped in the same F6 population between Criollo del Morelos 334 (CM334), a landrace from Mexico, and 'Early Jalapeno' using a high-density genetic map. Isolate-specific resistance was mapped independently in 63 of the lines evaluated and the two parents. Heritability of the resistance for each isolate at 3 and 5 days postinoculation (dpi) was high (h(2) = 0.63 to 0.68 and 0.74 to 0.83, respectively). Significant additive and epistatic quantitative trait loci (QTL) were identified for resistance to isolates OP97 and 13709 (3 and 5 dpi) and 12889 (3 dpi only). Mapping of fruit traits showed potential linkage with few disease resistance QTL. The partial fruit rot resistance from CM334 suggests that this may not be an ideal source for fruit rot resistance in pepper.
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143
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Pang Z, Shao J, Hu J, Chen L, Wang Z, Qin Z, Liu X. Competition between pyrimorph-sensitive and pyrimorph-resistant isolates of Phytophthora capsici. PHYTOPATHOLOGY 2014; 104:269-274. [PMID: 24093920 DOI: 10.1094/phyto-07-13-0185-r] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Phytophthora capsici causes significant losses to vegetable production worldwide. Pyrimorph, a new carboxylic acid amide fungicide, has been registered to control P. capsici in China. A mutation (Q1077K) in cellulose synthase 3 has been reported to confer resistance to pyrimorph. In this study, we measured the competition between pyrimorph-resistant and pyrimorph-sensitive isolates of P. capsici. Mixed zoospore suspensions of resistant (R) and sensitive (S) isolates at five ratios (1R:9S, 3R:7S, 5R:5S, 7R:3S, and 9R:1S) were applied to carrot agar in vitro test (with five successive transfers) and to the soil surface around pepper plants in planta test (with 10 successive disease cycles). The proportion of resistant isolates was measured by a conventional assay in which single zoospore isolates recovered after transfers or disease cycles were grown on agar medium with a discriminatory concentration of pyrimorph. The results were then compared with those of a real-time polymerase chain reaction (PCR)-based method developed here, the results were similar. Both assays showed that the competitive ability of the resistant isolates was similar to or less than that of the sensitive isolates. The real-time PCR assay developed will be useful for high-throughput analysis and monitoring the development of pyrimorph resistance in field populations of P. capsici.
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144
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Bi Y, Chen L, Cai M, Zhu S, Pang Z, Liu X. Two non-target recessive genes confer resistance to the anti-oomycete microtubule inhibitor zoxamide in Phytophthora capsici. PLoS One 2014; 9:e89336. [PMID: 24586697 PMCID: PMC3930715 DOI: 10.1371/journal.pone.0089336] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Accepted: 01/20/2014] [Indexed: 01/21/2023] Open
Abstract
This study characterized isolates of P. capsici that had developed a novel mechanism of resistance to zoxamide, which altered the minimum inhibition concentration (MIC) but not the EC50. Molecular analysis revealed that the β-tubulin gene of the resistant isolates contained no mutations and was expressed at the same level as in zoxamide-sensitive isolates. This suggested that P. capsici had developed a novel non-target-site-based resistance to zoxamide. Analysis of the segregation ratio of zoxamide-resistance in the sexual progeny of the sensitive isolates PCAS1 and PCAS2 indicated that the resistance to zoxamide was controlled by one or more recessive nuclear genes. Furthermore, the segregation of resistance in the F1, F2, and BC1 progeny was in accordance with the theoretical ratios of the χ(2) test (P>0.05), which suggested that the resistance to zoxamide was controlled by two recessive genes, and that resistance to zoxamide occurred when at least one pair of these alleles was homozygous. This implies that the risk of zoxamide-resistance in P. capsici is low to moderate. Nevertheless this potential for resistance should be monitored closely, especially if two compatible mating types co-exist in the same field.
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Affiliation(s)
- Yang Bi
- Department of Plant Pathology, China Agricultural University, Beijing, China
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Lei Chen
- Department of Plant Pathology, China Agricultural University, Beijing, China
- College of Forestry, Beijing Forestry University, Beijing, China
| | - Meng Cai
- Department of Plant Pathology, China Agricultural University, Beijing, China
| | - Shusheng Zhu
- Key Laboratory of Agro-Biodiversity and Pest Management of Education Ministry of China, Yunnan Agricultural University, Kunming, Yunnan, China
| | - Zhili Pang
- Department of Plant Pathology, China Agricultural University, Beijing, China
| | - Xili Liu
- Department of Plant Pathology, China Agricultural University, Beijing, China
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145
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Tareq FS, Lee MA, Lee HS, Lee YJ, Lee JS, Hasan CM, Islam MT, Shin HJ. Gageotetrins A–C, Noncytotoxic Antimicrobial Linear Lipopeptides from a Marine Bacterium Bacillus subtilis. Org Lett 2014; 16:928-31. [DOI: 10.1021/ol403657r] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Fakir Shahidullah Tareq
- Department
of Marine Biotechnology, University of Science and Technology, Republic of Korea
- Marine
Natural Products Laboratory, Korea Institute of Ocean Science and Technology, Republic of Korea
| | - Min Ah Lee
- Marine
Natural Products Laboratory, Korea Institute of Ocean Science and Technology, Republic of Korea
| | - Hyi-Seung Lee
- Marine
Natural Products Laboratory, Korea Institute of Ocean Science and Technology, Republic of Korea
| | - Yeon-Ju Lee
- Marine
Natural Products Laboratory, Korea Institute of Ocean Science and Technology, Republic of Korea
| | - Jong Seok Lee
- Marine
Natural Products Laboratory, Korea Institute of Ocean Science and Technology, Republic of Korea
| | - Choudhury M. Hasan
- Department
of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Dhaka, Bangladesh
| | - Md. Tofazzal Islam
- Department
of Biotechnology, Bangabandhu Sheikh Muzibur Rahman Agricultural University, Dhaka, Bangladesh
| | - Hee Jae Shin
- Department
of Marine Biotechnology, University of Science and Technology, Republic of Korea
- Marine
Natural Products Laboratory, Korea Institute of Ocean Science and Technology, Republic of Korea
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146
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Chowdappa P, Madhura S, Kumar BJN, Kumar SPM, Hema KR. Phytophthora boehmeriae Revealed as the Dominant Pathogen Responsible for Severe Foliar Blight of Capsicum annuum in South India. PLANT DISEASE 2014; 98:90-98. [PMID: 30708597 DOI: 10.1094/pdis-06-13-0601-re] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Prior to 2011, foliar blight was not reported as a serious threat to hot pepper cultivation in India. During the June-to-January cropping season of 2011 and 2012, severe foliar blight epidemics were observed in Karnataka and Tamil Nadu states of India. In all, 52 Phytophthora isolates, recovered from blight-affected leaf tissues of hot pepper from different localities in Karnataka and Tamil Nadu states between 2011 and 2012, were identified: 43 isolates as P. boehmeriae and 9 isolates as P. capsici, based on morphology, a similarity search of internal transcribed spacer sequences at GenBank, polymerase chain reaction (PCR) restriction fragment length polymorphism patterns, and species-specific PCR using PC1/PC2 and PB1/PB2 primer pairs. The isolates were further assessed for metalaxyl sensitivity and aggressiveness on hot pepper. All isolates of P. boehmeriae were metalaxyl sensitive while P. capsici isolates were intermediate in sensitivity. P. boehmeriae isolates were highly aggressive and produced significantly (P < 0.01) larger lesion than those of P. capsici isolates. Thus, emergence of P. boehmeriae was responsible for severe leaf blight epidemics on hot pepper in South India, although it is not serious pathogen on any crop in any part of the world. These results have epidemiological and management implications for the production of hot pepper in India.
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Affiliation(s)
- P Chowdappa
- Indian Institute of Horticultural Research, Hesaraghatta Lake Post, Bangalore-560 089, India
| | - S Madhura
- Indian Institute of Horticultural Research, Hesaraghatta Lake Post, Bangalore-560 089, India
| | - B J Nirmal Kumar
- Indian Institute of Horticultural Research, Hesaraghatta Lake Post, Bangalore-560 089, India
| | - S P Mohan Kumar
- Indian Institute of Horticultural Research, Hesaraghatta Lake Post, Bangalore-560 089, India
| | - K R Hema
- Indian Institute of Horticultural Research, Hesaraghatta Lake Post, Bangalore-560 089, India
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147
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Hu J, Diao Y, Zhou Y, Lin D, Bi Y, Pang Z, Trout Fryxell R, Liu X, Lamour K. Loss of heterozygosity drives clonal diversity of Phytophthora capsici in China. PLoS One 2013; 8:e82691. [PMID: 24349339 PMCID: PMC3861455 DOI: 10.1371/journal.pone.0082691] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2013] [Accepted: 11/05/2013] [Indexed: 11/24/2022] Open
Abstract
Phytophthora capsici causes significant loss to pepper (Capsicum annum) in China and our goal was to develop single nucleotide polymorphism (SNP) markers for P. capsici and characterize genetic diversity nationwide. Eighteen isolates of P. capsici from locations worldwide were re-sequenced and candidate nuclear and mitochondrial SNPs identified. From 2006 to 2012, 276 isolates of P. capsici were recovered from 136 locations in 27 provinces and genotyped using 45 nuclear and 2 mitochondrial SNPs. There were two main mitochondrial haplotypes and 95 multi-locus genotypes (MLGs) identified. Genetic diversity was geographically structured with a high level of genotypic diversity in the north and on Hainan Island in the south, suggesting outcrossing contributes to diversity in these areas. The remaining areas of China are dominated by four clonal lineages that share mitochondrial haplotypes, are almost exclusively the A1 or A2 mating type and appear to exhibit extensive diversity based on loss of heterozygosity (LOH). Analysis of SNPs directly from infected peppers confirmed LOH in field populations. One clonal lineage is dominant throughout much of the country. The overall implications for long-lived genetically diverse clonal lineages amidst a widely dispersed sexual population are discussed.
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Affiliation(s)
- Jian Hu
- Department of Plant Pathology, College of Agriculture and Biotechnology, China Agricultural University, Beijing, China
- Department of Entomology and Plant Pathology, University of Tennessee, Knoxville, Tennessee, United States of America
| | - Yongzhao Diao
- Department of Plant Pathology, College of Agriculture and Biotechnology, China Agricultural University, Beijing, China
| | - Yuxin Zhou
- Department of Entomology and Plant Pathology, University of Tennessee, Knoxville, Tennessee, United States of America
| | - Dong Lin
- Department of Plant Pathology, College of Agriculture and Biotechnology, China Agricultural University, Beijing, China
| | - Yang Bi
- Department of Plant Pathology, College of Agriculture and Biotechnology, China Agricultural University, Beijing, China
| | - Zhili Pang
- Department of Plant Pathology, College of Agriculture and Biotechnology, China Agricultural University, Beijing, China
| | - Rebecca Trout Fryxell
- Department of Entomology and Plant Pathology, University of Tennessee, Knoxville, Tennessee, United States of America
| | - Xili Liu
- Department of Plant Pathology, College of Agriculture and Biotechnology, China Agricultural University, Beijing, China
| | - Kurt Lamour
- Department of Entomology and Plant Pathology, University of Tennessee, Knoxville, Tennessee, United States of America
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148
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Capsicum annuum homeobox 1 (CaHB1) is a nuclear factor that has roles in plant development, salt tolerance, and pathogen defense. Biochem Biophys Res Commun 2013; 442:116-21. [DOI: 10.1016/j.bbrc.2013.11.019] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Accepted: 11/05/2013] [Indexed: 11/19/2022]
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149
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Özyilmaz Ü, Benlioglu K. Enhanced biological control of phytophthora blight of pepper by biosurfactant-producing pseudomonas. THE PLANT PATHOLOGY JOURNAL 2013; 29:418-26. [PMID: 25288970 PMCID: PMC4174822 DOI: 10.5423/ppj.oa.11.2012.0176] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2013] [Revised: 05/03/2013] [Accepted: 05/20/2013] [Indexed: 05/25/2023]
Abstract
Pseudomonas isolates from different crop plants were screened for in vitro growth inhibition of Phytophthora capsici and production of biosurfactant. Two in vivo experiments were performed to determine the efficacy of selected Pseudomonas strains against Phytophthora blight of pepper by comparing two fungicide treatments [acibenzolar-S-methyl (ASM) and ASM + mefenoxam]. Bacterial isolates were applied by soil drenching (1 × 10(9) cells/ml), ASM (0.1 μg a.i./ml) and ASM + mefenoxam (0.2 mg product/ml) were applied by foliar spraying, and P. capsici inoculum was incorporated into the pot soil three days after treatments. In the first experiment, four Pseudomonas strains resulted in significant reduction from 48.4 to 61.3% in Phytophthora blight severity. In the second experiment, bacterial treatments combining with olive oil (5 mL per plant) significantly enhanced biological control activity, resulting in a reduction of disease level ranging from 56.8 to 81.1%. ASM + mefenoxam was the most effective treatment while ASM alone was less effective in both bioassays. These results indicate that our Pseudomonas fluorescens strains (6L10, 6ba6 and 3ss9) that have biosurfactant-producing abilities are effective against P. capsici on pepper, and enhanced disease suppression could be achieved when they were used in combination with olive oil.
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Affiliation(s)
- Ümit Özyilmaz
- Adnan Menderes University, Faculty of Agriculture, Plant Protection Dept. 09100/Aydin, Turkey
| | - Kemal Benlioglu
- Adnan Menderes University, Faculty of Agriculture, Plant Protection Dept. 09100/Aydin, Turkey
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Babadoost M, Pavon C. Survival of Oospores of Phytophthora capsici in Soil. PLANT DISEASE 2013; 97:1478-1483. [PMID: 30708464 DOI: 10.1094/pdis-12-12-1123-re] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
This study assessed survival of Phytophthora capsici oospores in soil in Illinois. Soils differing in texture and other characteristics were collected from four Illinois Counties (Champaign, Gallatin, Madison, and Tazewell), equilibrated to -0.3 MPa, and infested with oospores of P. capsici at a density of 5 × 103 oospores/g of dry soil. Samples (25 g) of the infested soil were placed in 15-μm mesh polyester bags, which were sealed and placed at 2-, 10-, and 25-cm depths in 15.3-cm-diameter PVC tubes containing the same field soil as the infested bags. Tubes were buried vertically in the ground at the University of Illinois Vegetable Research Farm in Champaign in October 2004. Soil samples were assayed for recovery and germination of oospores 1 day and 3, 6, 12, 24, 30, 36, and 48 months after incorporation of oospores into the soil. Overall, the percentage of oospore recovery and the percentage of germination of oospores were not affected significantly by soil source and burial depth but both the oospore recovery and oospore germination were significantly (P = 0.001) affected by the duration of oospore burial. The rate of oospore recovery from soil samples was 61.06, 16.69, 10.28, 1.05, 0.30, 0.06, 0.05, and 0.004% after 1 day and 3, 6, 12, 24, 30, 36, and 48 months, respectively, following incorporation of oospores into the soil; and mean oospore germination was 47.17, 30.53, 21.33, 15.64, 7.42, 2.67, 2.61, and 0.00%, respectively. Survival of P. capsici oospores was compared in soil samples stored in a laboratory at 22°C versus on the soil surface or buried 2, 10, or 25 cm deep in a field. Oospores were recovered 1, 3, 6, 12, and 24 months after incorporation for both storage locations. The percentage of oospores recovered from samples stored in the laboratory was significantly (P = 0.004) greater than recovery from samples stored in the field, regardless of the depth of burial. Twenty-four months after incorporation of oospores, 26.52% of oospores were recovered from soil samples in the laboratory, whereas only 0.12% of oospores were recovered from soil samples in the field. Overall, the percentages of germination of oospores recovered from samples in the laboratory and field over 24 months were not significantly different. In both experiments, germinated oospores produced mycelia, sporangia, and zoospores, and were virulent on 'California Wonder' bell pepper. This study showed that oospores of P. capsici can survive and remain virulent in Illinois soils for more than 36 months but oospores were no longer viable after 48 months in soil in a field environment.
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Affiliation(s)
- M Babadoost
- Department of Crop Sciences, University of Illinois, Urbana 61801
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- Department of Crop Sciences, University of Illinois, Urbana 61801
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