1
|
Dar MS, Ahmad M, Yetoo NUN, Bhatt B, Bhat SN, Altaf H, Rafiqee S, Nabi A, Mohiddin FA, Gaafar ARZ, Mansoor S, Shah MD, Mushtaq M. Genetic footprint of population diversity and genetic structure of Venturia inaequalis infecting apple (Malus × domestica Borkh.). 3 Biotech 2023; 13:273. [PMID: 37449250 PMCID: PMC10335993 DOI: 10.1007/s13205-023-03672-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2023] [Accepted: 06/13/2023] [Indexed: 07/18/2023] Open
Abstract
Apple scab instigated by Venturia inaequalis impels remarkable losses to apple fruit production. In an effort to comprehend the key mechanisms of evolutionary potential defining V. inaequalis population, 132 isolates of V. inaequalis from five commercial apple orchards were collected and assayed using 14 microsatellite markers. The average diversity was observed within the individuals of populations based on the Shannon-Wieners index (I) and observed heterozygosity (Ho) was average but considerably lower than expected heterozygosity (He). The genetic differentiation based on FST values was revealed as an average measure of divergence between populations and had varying proportions of gene flow and migration among themselves. Analysis of Molecular Variance (AMOVA) revealed that variance (94%) was dispersed across individuals with a significant (6%) variation between populations from different regions. To examine host specialization within the V. inaequalis population, the assignment approach based on K-means of clustering (an unsupervised machine learning approach), revealed that the clustering method supported three clusters at (K = 3) and three major clusters were also observed in Principle Component Analysis (PCA). Additionally, Nei's genetic distance values, pairwise estimates of genetic differentiation, dendrogram using the neighbor-joining and PCoA revealed the random distribution of V. Inaequalis isolates that depicted a high proportion of genotypic diversity within populations and population genetic structure. Supplementary Information The online version contains supplementary material available at 10.1007/s13205-023-03672-2.
Collapse
Affiliation(s)
- Mohammad Saleem Dar
- Division of Plant Pathology, Faculty of Agriculture, SKUAST-Kashmir, Wadura, Sopore, Jammu and Kashmir 193201 India
| | - Mushtaq Ahmad
- Division of Plant Pathology, Faculty of Horticulture, SKUAST-Kashmir, Shalimar, Srinagar, Jammu and Kashmir 190025 India
| | - Nakeeb-Un-Nisa Yetoo
- Division of Genetics and Plant Breeding, FoA, SKUAST-K, Wadura, Sopore, Jammu and Kashmir 193201 India
| | - Bhagyshree Bhatt
- MS Swaminathan School of Agriculture, Shoolini University of Biotechnology and Management Sciences, Bajhol, Solan, Himachal Pradesh 173229 India
| | - Suhail Nazir Bhat
- Division of Fruit Science, Faculty of Horticulture, SKUAST-Kashmir, Shalimar, Srinagar, Jammu and Kashmir 190025 India
| | - Heena Altaf
- Division of Plant Pathology, Faculty of Agriculture, SKUAST-Kashmir, Wadura, Sopore, Jammu and Kashmir 193201 India
| | - Sumira Rafiqee
- Division of Genetics and Plant Breeding, FoA, SKUAST-K, Wadura, Sopore, Jammu and Kashmir 193201 India
| | - Asha Nabi
- Division of Plant Pathology, Faculty of Agriculture, SKUAST-Kashmir, Wadura, Sopore, Jammu and Kashmir 193201 India
| | - F. A. Mohiddin
- Mountain Research Centre for Field Crops, SKUAST-Kashmir, Khudwani, Kulgam, Jammu and Kashmir 192101 India
| | - Abdel-Rhman Z. Gaafar
- Department of Botany and Microbiology, College of Science, King Saud University, P.O. Box 11451, Riyadh, Saudi Arabia
| | - Sheikh Mansoor
- Department of Plant Resources and Environment, Jeju National University, Jeju, 63243 Republic of Korea
| | - Mehraj D. Shah
- Division of Plant Pathology, Faculty of Horticulture, SKUAST-Kashmir, Shalimar, Srinagar, Jammu and Kashmir 190025 India
| | - Muntazir Mushtaq
- MS Swaminathan School of Agriculture, Shoolini University of Biotechnology and Management Sciences, Bajhol, Solan, Himachal Pradesh 173229 India
| |
Collapse
|
2
|
Lü Z, Hui N, Wang L, Zheng G, Wang S, Li J. Genetic diversity of Venturia inaequalis isolates from the scabs in apple trees in Gansu Province, China, using AFLP markers. PeerJ 2022; 10:e14512. [PMID: 36545382 PMCID: PMC9762247 DOI: 10.7717/peerj.14512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Accepted: 11/14/2022] [Indexed: 12/23/2022] Open
Abstract
Apple scab is a serious disease that restricts the growth of cultivated apples. The objective of this study is to investigate the genetic variations and genetic structure of Venturia inaequalis in Gansu Province, China. 108 isolates of the pathogen V. inaequalis from the Jingning, Lingtai, Jingchuan, Xifeng, Ning and Maiji regions were collected, and their genetic diversity was analyzed using AFLP molecular marker technique. The results showed that genetic diversity was present among the isolates but was not statistically significant. Genetic distance values ranged from 0.0095 to 0.0762. Cluster analysis results showed that the 108 isolates could be divided into two clusters using a similarity coefficient of 0.69. A total of 104 isolates were contained in cluster I while four isolates were contained in Cluster II. From the AMOVA analysis, 98% of variations were observed within the same region, while 2% were observed across different regions. The analysis of population structure showed that 108 isolates had two common ancestors, with the Jingning isolates mainly being derived from the red ancestor. PCoA analysis showed that the Jingning isolates were independent to a certain extent. The different geographical location caused the genetic difference of the isolates. The genetic diversity of apple scab in Gansu Province is greatly aided by this work, which also offers a theoretical foundation for the use of molecular markers in assisted breeding to create novel resistant types.
Collapse
Affiliation(s)
- Zhaolong Lü
- College of Plant Protection, Gansu Agricultural University, Lanzhou, China
- Institute of Plant Protection, Gansu Academy of Agricultural Sciences, Lanzhou, China
| | - Nana Hui
- Institute of Plant Protection, Gansu Academy of Agricultural Sciences, Lanzhou, China
| | - Li Wang
- Institute of Plant Protection, Gansu Academy of Agricultural Sciences, Lanzhou, China
| | - Guo Zheng
- Institute of Plant Protection, Gansu Academy of Agricultural Sciences, Lanzhou, China
| | - Senshan Wang
- College of Plant Protection, Gansu Agricultural University, Lanzhou, China
| | - Jiping Li
- College of Plant Protection, Gansu Agricultural University, Lanzhou, China
- Institute of Plant Protection, Gansu Academy of Agricultural Sciences, Lanzhou, China
| |
Collapse
|
3
|
Sokolova O, Moročko-Bičevska I, Lācis G. Genetic Diversity of Venturia inaequalis in Latvia Revealed by Microsatellite Markers. Pathogens 2022; 11:1165. [PMID: 36297222 PMCID: PMC9611756 DOI: 10.3390/pathogens11101165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 09/30/2022] [Accepted: 10/03/2022] [Indexed: 11/22/2022] Open
Abstract
Apple scab caused by the ascomycete Venturia inaequalis is an economically significant disease worldwide. The annual sexual reproduction of V. inaequalis leads to high variation, changes in the population's genetic structure and adaptations to the changing environment, including overcoming the host's resistance. The objective of this study is to characterise and assess the genetic diversity of V. inaequalis populations in two main apple-growing regions in Latvia. In total, 143 V. inaequalis isolates were collected from Latvia, six reference strains with known virulence were obtained from other countries, and all strains were genotyped by 12 SSR markers. The SSR markers were highly variable and informative, identifying 158 alleles that ranged from two to 29 per locus. The Bayesian clustering identified three genetic lineages among the Latvian isolates that did not correlate to the geographic origin, host genotype, organ (leaves or fruits) from which the pathogen was isolated, time of collection, and type of isolation (single conidium or ascospore). The possible relatedness to virulence was detected when reference strains with known virulence were included in the analysis. Our findings correspond with previous studies demonstrating that V. inaequalis in Europe has a high genetic diversity within populations, but low diversity among the populations.
Collapse
Affiliation(s)
- Olga Sokolova
- Institute of Horticulture, Latvia University of Life Sciences and Technologies, LV-3701 Dobele, Latvia
- Institute of Soil and Plant Sciences, Latvia University of Life Sciences and Technologies, Lielā str. 2, LV-3001 Jelgava, Latvia
| | - Inga Moročko-Bičevska
- Institute of Horticulture, Latvia University of Life Sciences and Technologies, LV-3701 Dobele, Latvia
| | - Gunārs Lācis
- Institute of Horticulture, Latvia University of Life Sciences and Technologies, LV-3701 Dobele, Latvia
| |
Collapse
|
4
|
Bock CH, Frusso E, Zoppolo R, Ortiz ER, Shiller J, Charlton ND, Young CA, Randall JJ. Population Genetic Characteristics and Mating Type Frequency of Venturia effusa from Pecan in South America. PHYTOPATHOLOGY 2022; 112:2224-2235. [PMID: 35596236 DOI: 10.1094/phyto-01-22-0031-r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Scab, caused by the plant-pathogenic fungus Venturia effusa, is a major disease of pecan in South America, resulting in loss of quantity and quality of nut yield. Characteristics of the populations of V. effusa in South America are unknown. We used microsatellites to describe the genetic diversity and population structure of V. effusa in South America, and determined the mating type status of the pathogen. The four hierarchically sampled orchard populations from Argentina (AR), Brazil (BRC and BRS), and Uruguay (UR) had moderate to high genotypic and gene diversity. There was evidence of population differentiation (Fst = 0.196) but the correlation between geographic distance and genetic distance was not statistically significant. Genetic differentiation was minimal between the UR, BRC, and BRS populations, and these populations were more clearly differentiated from the AR population. The MAT1-1 and MAT1-2 mating types occurred in all four orchards and their frequencies did not deviate from the 1:1 ratio expected under random mating; however, multilocus linkage equilibrium was rejected in three of the four populations. The population genetics of South American populations of V. effusa has many similarities to the population genetics of V. effusa previously described in the United States. Characterizing the populations genetics and reproductive systems of V. effusa are important to establish the evolutionary potential of the pathogen and, thus, its adaptability-and can provide a basis for informed approaches to utilizing available host resistance and determining phytosanitary needs.
Collapse
Affiliation(s)
- Clive H Bock
- United States Department of Agriculture-Agriculture Research Service, Southeastern Fruit and Tree Nut Research Lab, 21 Dunbar Road, Byron, GA 31008, U.S.A
| | - Enrique Frusso
- Instituto de Recursos Biológicos, INTA Castelar, Las Cabañas y De Los Reseros s.n., (1686) Hurlingham, Buenos Aires, Argentina
| | - Roberto Zoppolo
- Instituto Nacional de Investigación Agropecuaria - INIA Las Brujas, Ruta 48 - km 10, El Colorado, Canelones, Uruguay, CP 90200
| | - Edson R Ortiz
- Divinut Indústria de Nozes Ltda., Rodovia BR-153, km 375, CEP 96504-800 - Cachoeira do Sul/RS, Brazil
| | | | - Nikki D Charlton
- Noble Research Institute, 2510 Sam Noble Parkway, Ardmore, OK 73401, U.S.A
| | - Carolyn A Young
- Noble Research Institute, 2510 Sam Noble Parkway, Ardmore, OK 73401, U.S.A
- Department of Entomology and Plant Pathology, Oklahoma State University, Stillwater, 74078, U.S.A
| | | |
Collapse
|
5
|
Genetic diversity of Venturia inaequalis isolates (Apple scab) in China and U.K. determined by SSR markers. PLoS One 2021; 16:e0252865. [PMID: 34111167 PMCID: PMC8191898 DOI: 10.1371/journal.pone.0252865] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2020] [Accepted: 05/24/2021] [Indexed: 11/21/2022] Open
Abstract
Apple scab caused by Venturia inaequalis is a serious disease of cultivated apple worldwide. In this study, we collected 132 V. inaequalis isolates from Shaanxi, Gansu, Xinjiang, and the U.K. and analyzed their genetic diversity by using 13 microsatellite markers. Cluster analysis based on population structure and genetic distances suggested high similarity among the four regions. Population differentiation values ranged from 0.044 to 0.155, indicating there is a high level of kinship among the four regions. All isolates could be divided into 5 lineages with a 0.76 similarity coefficient. Among the four regions, Shaanxi had only one lineage, Group II; Gansu had four lineages, Group I, Group II, Group IV, and Group V; Xinjiang had all five lineages, Group I, Group II, Group III, Group IV, and Group V; and the U.K. had three lineages, Group I, Group II and Group IV. High molecular variance was detected for populations in the four regions, with 91% of the variance occurring within the populations and 9% among the populations. Structure analysis there are three common ancestors of these four regions. The results of the present study shed light on the genetic diversity of V. inaequalis in Shaanxi, Gansu and Xinjiang, which will lead to the development of more effective management strategies and new resistant apple cultivars through molecular marker-assisted selection.
Collapse
|
6
|
Dar MS, Padder BA, Ahmad M, Sofi TA, Mir AA, Nabi A, Shah MD. Population structure of Venturia inaequalis, a hemibiotrophic fungus, under different host resistance specificities in the Kashmir valley. Arch Microbiol 2020; 202:2245-2253. [PMID: 32533207 DOI: 10.1007/s00203-020-01950-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Revised: 05/08/2020] [Accepted: 05/11/2020] [Indexed: 11/25/2022]
Abstract
Venturia inaequalis is a notorious fungal pathogen and show classical gene for gene interaction with its apple host. Neutral markers provide clues about history, evolutionary potential, genetic diversity and population structure of V. inaequalis. The genetic diversity and population structure of fungus indicates that the pathogen is highly diverse with the capacity to breach the scab resistance genes. In the present study, we collected 108 V. inaequalis isolates from three apple cultivars differing in Rvi1 resistance gene. Based on the AMOVA, the variation was mostly distributed among the isolates, providing evidence of non-existence of subpopulation in orchards thus founder population is difficult to arise in Kashmir apple orchards. Pair wise genetic differentiation is less due to regular occurrence of gene flow between the populations residing on different orchard as infected material is transported without stringent quarantine measures. Based on principal coordinate analysis and clustering algorithm as implemented in STRUCTURE, we observed admixture between the two subpopulations, which is quite low, suggesting the existence of pre-zygotic and post-zygotic barriers to gene flow and we cannot rule out the existence of other structures shared by accessions belonging to different varieties. Due to the continuous increase in introduction and monoculture of apple varieties, mixed orchard with different host resistance specificities are more suitable for managing the apple scab in Kashmir valley.
Collapse
Affiliation(s)
- M S Dar
- Plant Virology and Molecular Plant Pathology Laboratory, Division of Plant Pathology, SKUAST-Kashmir, Shalimar, Srinagar, 190025, India
| | - Bilal A Padder
- Plant Virology and Molecular Plant Pathology Laboratory, Division of Plant Pathology, SKUAST-Kashmir, Shalimar, Srinagar, 190025, India.
| | - Mushtaq Ahmad
- Plant Virology and Molecular Plant Pathology Laboratory, Division of Plant Pathology, SKUAST-Kashmir, Shalimar, Srinagar, 190025, India
| | - T A Sofi
- Plant Virology and Molecular Plant Pathology Laboratory, Division of Plant Pathology, SKUAST-Kashmir, Shalimar, Srinagar, 190025, India
| | - A A Mir
- Plant Virology and Molecular Plant Pathology Laboratory, Division of Plant Pathology, SKUAST-Kashmir, Shalimar, Srinagar, 190025, India
| | - Asha Nabi
- Division of Plant Pathology, Faculty of Agriculture, SKUAST-K, Sopore, Wadura, 193201, India
| | - M D Shah
- Plant Virology and Molecular Plant Pathology Laboratory, Division of Plant Pathology, SKUAST-Kashmir, Shalimar, Srinagar, 190025, India
| |
Collapse
|
7
|
A Descriptive Study on Attitudes Toward Local Health Resource Allocation: The Case of Chongqing Province in China. HEALTH SCOPE 2019. [DOI: 10.5812/jhealthscope.91737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
8
|
Elucidating genetic variability and population structure in Venturia inaequalis associated with apple scab diseaseusing SSR markers. PLoS One 2019; 14:e0224300. [PMID: 31693681 PMCID: PMC6834240 DOI: 10.1371/journal.pone.0224300] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Accepted: 10/09/2019] [Indexed: 01/20/2023] Open
Abstract
Apple scab caused by Venturia inaequalis Cooke (Wint.) is one the important diseases of trade and industrial significance in apple. In present study variability studies in pathogen isolates were studied, which is one of the most important factors for devising management studies of scab disease in apple. Genetic diversity of 30 Venturia inaequalis isolates from 12 districts of two geographical distinct regions of Jammu and Kashmir was calculated based on the allele frequencies of 28 SSR markers and the internal transcribed spacer (ITS) region of the ribosomal DNA. The ITS based characterized sequences were submitted to NCBI GenBank and accession numbers were sanctioned. Dendrogram showed that all the accessions formed 2 main clusters with various degree of sub clustering within the clusters. Analysis based on SSR study reveals that the heterozygosity ranged from 0.0 and 0.5, with an average value of 0.39. The expected heterozygosis or gene diversity (He) ranged from 0.0 to 0.50 with an average of 0.40. The Fst value ranges from 0 to 0.6 with an average of 0.194. Diversity within each population (HS) values ranging from 0.26 to 0.33. Average differentiation among populations (GST) was 0.11 and populations were isolated by significant distance (r 2 = 0.50, P < 0.01). From the AMOVA analysis, 25% of variation was observed among population, 9% among individuals and 66% within individuals observed in the population. Structure analysis grouped isolates into two populations. Principle coordinate analysis explained variation of 36.6% in population 1, 14.30% in population 2 and 13.10% in population 3(Admixture) with 64.07% as overall cumulative percentage of variation. This indicates that extensive short-distance gene flow occurs in Kashmir region that dispersal over longer distances also appears to occur frequently enough to prevent differentiation due to genetic drift. Also it is evident that Jammu and Kashmir most likely has V. inaequalis subpopulations linked to diverse climatic conditions of the Jammu region compared to the mountainous inland Kashmir region. The results of present study would help to understand the genetic diversity of V. inaequalis from Jammu and Kashmir that would lead in the development of more effective management strategies and development of new resistant cultivars through marker-assisted selection.
Collapse
|
9
|
Mining and characterization of microsatellites from a genome of Venturia carpophila. Mycol Prog 2018. [DOI: 10.1007/s11557-018-1401-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
|
10
|
González-Domínguez E, Armengol J, Rossi V. Biology and Epidemiology of Venturia Species Affecting Fruit Crops: A Review. FRONTIERS IN PLANT SCIENCE 2017; 8:1496. [PMID: 28974954 PMCID: PMC5610699 DOI: 10.3389/fpls.2017.01496] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Accepted: 08/14/2017] [Indexed: 05/19/2023]
Abstract
The fungal genus Venturia Sacc. (anamorph Fusicladium Bonord.) includes plant pathogens that cause substantial economic damage to fruit crops worldwide. Although Venturia inaequalis is considered a model species in plant pathology, other Venturia spp. also cause scab on other fruit trees. Relative to the substantial research that has been conducted on V. inaequalis and apple scab, little research has been conducted on Venturia spp. affecting other fruit trees. In this review, the main characteristics of plant-pathogenic species of Venturia are discussed with special attention to V. inaequalis affecting apple, V. pyrina affecting European pear, V. nashicola affecting Asian pear, V. carpophila affecting peach and almond, Fusicladium oleagineum affecting olive, F. effusum affecting pecan, and F. eriobotryae affecting loquat. This review has two main objectives: (i) to identify the main gaps in our knowledge regarding the biology and epidemiology of Venturia spp. affecting fruit trees; and (ii) to identify similarities and differences among these Venturia spp. in order to improve disease management. A thorough review has been conducted of studies regarding the phylogenetic relationships, host ranges, biologies, and epidemiologies of Venturia spp. A multiple correspondence analysis (CA) has also been performed on the main epidemiological components of these Venturia spp. CA separated the Venturia spp. into two main groups, according to their epidemiological behavior: the first group included V. inaequalis, V. pyrina, V. nashicola, and V. carpophila, the second F. oleagineum and F. eriobotryae, with F. effusum having an intermediate position. This review shows that Venturia spp. affecting fruit trees are highly host-specific, and that important gaps in understanding the life cycle exist for some species, including V. pyrina; gaps include pseudothecia formation, ascospore and conidia germination, and mycelial growth. Considering the epidemiological information reviewed, this paper shows that the use of Mills tables to predict infection periods should be avoided for Venturia spp. other than V. inaequalis.
Collapse
Affiliation(s)
| | - Josep Armengol
- Instituto Agroforestal Mediterráneo, Universitat Politècnica de ValènciaValencia, Spain
| | - Vittorio Rossi
- Department of Sustainable Crop Protection, Università Cattolica del Sacro CuorePiacenza, Italy
| |
Collapse
|
11
|
Koopman TA, Meitz-Hopkins JC, Bester-van der Merwe AE, Tobutt KR, Bester C, Lennox CL. Genetic Diversity and Gene Flow of Four South African Venturia inaequalis (Apple Scab) Populations. PHYTOPATHOLOGY 2017; 107:455-462. [PMID: 27868478 DOI: 10.1094/phyto-07-16-0279-r] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Venturia inaequalis isolates were collected during the 2012/13 and 2013/14 seasons from the four principal apple growing regions of South Africa, Elgin (n = 114), Koue Bokkeveld (n = 126), Lower Langkloof (n = 92), and Upper Langkloof (n = 103). Sequence analysis of the ribosomal internal transcribed spacer (ITS) gene regions and genotyping with six (2012/13) and seven (2013/14) microsatellite (SSR) markers was conducted. A subset of 12 isolates from the individual ITS haplotype groups were sequenced for the translation elongation factor-1 alpha (TEF1) and the large subunit of the RNA polymerases II (RPB1) gene regions. Four haplotypes were found for ITS, whereas all isolates were identical for the TEF1 and RPB1 gene regions. The SSR markers revealed considerable variation with an average gene diversity (H) of 0.675. Multivariate analysis (discriminant analysis of principal components [DAPC]) revealed that the two Langkloof populations clustered together with the Koue Bokkeveld population. The population from the warmer winter region, Elgin, clustered separately from the rest of the populations (ΦPT = 0.076 to 0.116; P ≤ 0.05). Estimates of gene flow showed the highest migration rate from the Koue Bokkeveld, toward the Lower Langkloof (M = 151.1), and the least migration to and from the Elgin region (average M = 42.75). Occasionally, identical genotypes (clones) were detected across seasons in the Koue Bokkeveld and Elgin area, which might contribute to overwintering conidia. From this study, it is evident that South Africa most likely has V. inaequalis subpopulations linked to diverse climatic conditions of the coastal Elgin region compared with the mountainous inland regions of the Koue Bokkeveld and the Langkloof.
Collapse
Affiliation(s)
- T A Koopman
- First, fourth, and fifth authors: Agricultural Research Council Infruitec-Nietvoorbij (Institute of Deciduous Fruit), Private Bag X5026, Stellenbosch 7599, South Africa; first, second, and sixth authors: Fruit and Postharvest Pathology Research Programme, Department of Plant Pathology, Stellenbosch University, Private Bag X1, Matieland, Stellenbosch 7602, South Africa; and third author: Department of Genetics, Stellenbosch University, Private Bag X1, Matieland, Stellenbosch 7602, South Africa
| | - J C Meitz-Hopkins
- First, fourth, and fifth authors: Agricultural Research Council Infruitec-Nietvoorbij (Institute of Deciduous Fruit), Private Bag X5026, Stellenbosch 7599, South Africa; first, second, and sixth authors: Fruit and Postharvest Pathology Research Programme, Department of Plant Pathology, Stellenbosch University, Private Bag X1, Matieland, Stellenbosch 7602, South Africa; and third author: Department of Genetics, Stellenbosch University, Private Bag X1, Matieland, Stellenbosch 7602, South Africa
| | - A E Bester-van der Merwe
- First, fourth, and fifth authors: Agricultural Research Council Infruitec-Nietvoorbij (Institute of Deciduous Fruit), Private Bag X5026, Stellenbosch 7599, South Africa; first, second, and sixth authors: Fruit and Postharvest Pathology Research Programme, Department of Plant Pathology, Stellenbosch University, Private Bag X1, Matieland, Stellenbosch 7602, South Africa; and third author: Department of Genetics, Stellenbosch University, Private Bag X1, Matieland, Stellenbosch 7602, South Africa
| | - K R Tobutt
- First, fourth, and fifth authors: Agricultural Research Council Infruitec-Nietvoorbij (Institute of Deciduous Fruit), Private Bag X5026, Stellenbosch 7599, South Africa; first, second, and sixth authors: Fruit and Postharvest Pathology Research Programme, Department of Plant Pathology, Stellenbosch University, Private Bag X1, Matieland, Stellenbosch 7602, South Africa; and third author: Department of Genetics, Stellenbosch University, Private Bag X1, Matieland, Stellenbosch 7602, South Africa
| | - C Bester
- First, fourth, and fifth authors: Agricultural Research Council Infruitec-Nietvoorbij (Institute of Deciduous Fruit), Private Bag X5026, Stellenbosch 7599, South Africa; first, second, and sixth authors: Fruit and Postharvest Pathology Research Programme, Department of Plant Pathology, Stellenbosch University, Private Bag X1, Matieland, Stellenbosch 7602, South Africa; and third author: Department of Genetics, Stellenbosch University, Private Bag X1, Matieland, Stellenbosch 7602, South Africa
| | - C L Lennox
- First, fourth, and fifth authors: Agricultural Research Council Infruitec-Nietvoorbij (Institute of Deciduous Fruit), Private Bag X5026, Stellenbosch 7599, South Africa; first, second, and sixth authors: Fruit and Postharvest Pathology Research Programme, Department of Plant Pathology, Stellenbosch University, Private Bag X1, Matieland, Stellenbosch 7602, South Africa; and third author: Department of Genetics, Stellenbosch University, Private Bag X1, Matieland, Stellenbosch 7602, South Africa
| |
Collapse
|
12
|
Ebrahimi L, Fotuhifar KB, Javan Nikkhah M, Naghavi MR, Baisakh N. Population Genetic Structure of Apple Scab (Venturia inaequalis (Cooke) G. Winter) in Iran. PLoS One 2016; 11:e0160737. [PMID: 27631622 PMCID: PMC5025049 DOI: 10.1371/journal.pone.0160737] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Accepted: 08/27/2016] [Indexed: 11/19/2022] Open
Abstract
The population genetic structure of 278 Venturia inaequalis isolates, collected from different apple cultivars of eighteen different provinces in Iran, was investigated using 22 polymorphic microsatellite markers. Analysis of molecular variation, Bayesian clustering and Nei's genetic distance analyses based on 88 microsatellite alleles indicated substantial levels of gene flow among the collection sites. Ninety three percent of the variation was observed among the individuals within the populations and only 7% variation was observed among the populations. Structure analysis grouped the isolates into two populations. Maximum number of pathogen genotypes (44) was observed in the North of Iran that grows various different apple cultivars. Investigation on the variation of the pathogen on different cultivars in the North of Iran suggested a significant differentiation of the pathogen populations between wild apple and commercial cultivars. During sampling, varying ranges of scab infection were observed on various apple cultivars in forests, monoculture and mix orchards. Wild type apple (Malus orientalis) along the Caspian Sea Coast had the most infection in comparison with the Iranian endemic and commercial cultivars. Based on the genetic analysis and host tracking scenario of the pathogen, it was presumed that Iran could potentially be the center of origin of V. inaequalis, which requires further detailed studies with isolates collected from different parts of central Asia and world for confirmation.
Collapse
Affiliation(s)
- Leila Ebrahimi
- Department of Plant Pathology, Faculty of Agricultural Sciences and Engineering, College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran
- School of Plant, Environmental and Soil Sciences, Louisiana State University Agricultural Center, Baton Rouge, LA, 70803, United States of America
| | - Khalil-Berdi Fotuhifar
- Department of Plant Pathology, Faculty of Agricultural Sciences and Engineering, College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran
| | - Mohammad Javan Nikkhah
- Department of Plant Pathology, Faculty of Agricultural Sciences and Engineering, College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran
| | - Mohammad-Reza Naghavi
- Department of Biotechnology, Faculty of Agricultural Sciences and Engineering, College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran
| | - Niranjan Baisakh
- School of Plant, Environmental and Soil Sciences, Louisiana State University Agricultural Center, Baton Rouge, LA, 70803, United States of America
| |
Collapse
|
13
|
Bus VG, Rikkerink EH, Caffier V, Durel CE, Plummer KM. Revision of the Nomenclature of the Differential Host-Pathogen Interactions of Venturia inaequalis and Malus. ANNUAL REVIEW OF PHYTOPATHOLOGY 2011; 49:391-413. [PMID: 0 DOI: 10.1146/annurev-phyto-072910-095339] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The apple scab (Venturia inaequalis–Malus) pathosystem was one of the first systems for which Flor's concept of gene-for-gene (GfG) relationships between the host plant and the pathogen was demonstrated. There is a rich resource of host resistance genes present in Malus germplasm that could potentially be marshalled to confer durable resistance against this most important apple disease. A comprehensive understanding of the host-pathogen interactions occurring in this pathosystem is a prerequisite for effectively manipulating these host resistance factors. An accurate means of identification of specific resistance and consistent use of gene nomenclature is critical for this process. A set of universally available, differentially resistant hosts is described, which will be followed by a set of defined pathogen races at a later stage. We review pertinent aspects of the history of apple scab research, describe the current status and future directions of this research, and resolve some outstanding issues.
Collapse
Affiliation(s)
- Vincent G.M. Bus
- The Plant and Food Research Institute of New Zealand, Private Bag 1401, Havelock North 4157, New Zealand
| | - Erik H.A. Rikkerink
- The Plant and Food Research Institute of New Zealand, Private Bag 92169, Auckland 1142, New Zealand
| | - Valérie Caffier
- INRA, UMR77 Pathologie Végétale – PaVé, INRA/ACO/UA, IFR QUASAV, BP 60057, F-49071 Beaucouzé, France
| | - Charles-Eric Durel
- INRA, UMR 1259 Genetics and Horticulture – GenHort, INRA/ACO/UA, IFR QUASAV, BP 60057, F-49071 Beaucouzé, France
| | - Kim M. Plummer
- La Trobe University, Department of Botany, Bundoora, Vic. 3086, Australia
| |
Collapse
|
14
|
Jha G, Thakur K, Thakur P. The Venturia apple pathosystem: pathogenicity mechanisms and plant defense responses. J Biomed Biotechnol 2010; 2009:680160. [PMID: 20150969 PMCID: PMC2817808 DOI: 10.1155/2009/680160] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2009] [Revised: 08/10/2009] [Accepted: 10/29/2009] [Indexed: 11/19/2022] Open
Abstract
Venturia inaequalis is the causal agent of apple scab, a devastating disease of apple. We outline several unique features of this pathogen which are useful for molecular genetics studies intended to understand plant-pathogen interactions. The pathogenicity mechanisms of the pathogen and overview of apple defense responses, monogenic and polygenic resistance, and their utilization in scab resistance breeding programs are also reviewed.
Collapse
Affiliation(s)
- Gopaljee Jha
- Biotechnology Division, Institute of Himalayan Bioresource Technology, Council of Scientific and Industrial Research, Palampur 176061, Himachal Pradesh, India
| | - Karnika Thakur
- Biotechnology Division, Institute of Himalayan Bioresource Technology, Council of Scientific and Industrial Research, Palampur 176061, Himachal Pradesh, India
| | - Priyanka Thakur
- Biotechnology Division, Institute of Himalayan Bioresource Technology, Council of Scientific and Industrial Research, Palampur 176061, Himachal Pradesh, India
| |
Collapse
|
15
|
Gao L, Berrie A, Yang J, Xu X. Within- and between-orchard variability in the sensitivity of Venturia inaequalis to myclobutanil, a DMI fungicide, in the UK. PEST MANAGEMENT SCIENCE 2009; 65:1241-1249. [PMID: 19606427 DOI: 10.1002/ps.1816] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
BACKGROUND Myclobutanil, a demethylation inhibitor (DMI) fungicide, is an important fungicide for controlling apple scab and powdery mildew. Overuse of this fungicide has led to establishment of scab isolates with reduced sensitivity to this fungicide in several countries. Experiments were conducted to determine the sensitivity of the causal agent of apple scab, Venturia inaequalis (Cooke) Winter, to myclobutanil in the UK, in order to assess whether there is a relationship between fungal insensitivity and the number of DMI applications, and establishing whether fungal sensitivity varied greatly within an orchard. RESULTS Reduced sensitivity of V. inaequalis to myclobutanil was positively related linearly to the number of DMI applications. ED(50) values ranged from 0.028 to 1.017 mg L(-1) (average = 0.292) for the baseline population, whereas isolates from two other orchards had much greater ED(50) values, ranging from 0.085 to 5.213 mg L(-1) (average = 1.852). There was significant variation in fungal sensitivity to myclobutanil among fungal isolates from different locations within a single orchard. CONCLUSIONS Spatial spread of insensitive isolates of V. inaequalis to myclobutanil is likely to be limited in distance. Conidia may be an important source of primary inoculum. Myclobutanil should still be effective for most field isolates, but its use should be strategically integrated with other groups of fungicides.
Collapse
Affiliation(s)
- Liqiang Gao
- College of Crop Protection, Northwest A&F University, Yangling, Shaanxi Province, PR China
| | | | | | | |
Collapse
|