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Yuan P, Huang PC, Martin TK, Chappell TM, Kolomiets MV. Duplicated Copy Number Variant of the Maize 9-Lipoxygenase ZmLOX5 Improves 9,10-KODA-Mediated Resistance to Fall Armyworms. Genes (Basel) 2024; 15:401. [PMID: 38674336 PMCID: PMC11049851 DOI: 10.3390/genes15040401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2024] [Revised: 03/19/2024] [Accepted: 03/22/2024] [Indexed: 04/28/2024] Open
Abstract
Extensive genome structure variations, such as copy number variations (CNVs) and presence/absence variations, are the basis for the remarkable genetic diversity of maize; however, the effect of CNVs on maize herbivory defense remains largely underexplored. Here, we report that the naturally occurring duplication of the maize 9-lipoxygenase gene ZmLOX5 leads to increased resistance of maize to herbivory by fall armyworms (FAWs). Previously, we showed that ZmLOX5-derived oxylipins are required for defense against chewing insect herbivores and identified several inbred lines, including Yu796, that contained duplicated CNVs of ZmLOX5, referred to as Yu796-2×LOX5. To test whether introgression of the Yu796-2×LOX5 locus into a herbivore-susceptible B73 background that contains a single ZmLOX5 gene is a feasible approach to increase resistance, we generated a series of near-isogenic lines that contained either two, one, or zero copies of the Yu796-2×LOX5 locus in the B73 background via six backcrosses (BC6). Droplet digital PCR (ddPCR) confirmed the successful introgression of the Yu796-2×LOX5 locus in B73. The resulting B73-2×LOX5 inbred line displayed increased resistance against FAW, associated with increased expression of ZmLOX5, increased wound-induced production of its primary oxylipin product, the α-ketol, 9-hydroxy-10-oxo-12(Z),15(Z)-octadecadienoic acid (9,10-KODA), and the downstream defense hormones regulated by this molecule, 12-oxo-phytodienoic acid (12-OPDA) and abscisic acid (ABA). Surprisingly, wound-induced JA-Ile production was not increased in B73-2×LOX5, resulting from the increased JA catabolism. Furthermore, B73-2×LOX5 displayed reduced water loss in response to drought stress, likely due to increased ABA and 12-OPDA content. Taken together, this study revealed that the duplicated CNV of ZmLOX5 quantitively contributes to maize antiherbivore defense and presents proof-of-concept evidence that the introgression of naturally occurring duplicated CNVs of a defensive gene into productive but susceptible crop varieties is a feasible breeding approach for enhancing plant resistance to herbivory and tolerance to abiotic stress.
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Affiliation(s)
| | | | | | | | - Michael V. Kolomiets
- Department of Plant Pathology and Microbiology, Texas A&M University, College Station, TX 77840-2132, USA; (P.Y.); (P.-C.H.); (T.K.M.); (T.M.C.)
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2
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McLaughlin CM, Li M, Perryman M, Heymans A, Schneider H, Lasky JR, Sawers RJH. Evidence that variation in root anatomy contributes to local adaptation in Mexican native maize. Evol Appl 2024; 17:e13673. [PMID: 38468714 PMCID: PMC10925829 DOI: 10.1111/eva.13673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Revised: 02/07/2024] [Accepted: 02/22/2024] [Indexed: 03/13/2024] Open
Abstract
Mexican native maize (Zea mays ssp. mays) is adapted to a wide range of climatic and edaphic conditions. Here, we focus specifically on the potential role of root anatomical variation in this adaptation. Given the investment required to characterize root anatomy, we present a machine-learning approach using environmental descriptors to project trait variation from a relatively small training panel onto a larger panel of genotyped and georeferenced Mexican maize accessions. The resulting models defined potential biologically relevant clines across a complex environment that we used subsequently for genotype-environment association. We found evidence of systematic variation in maize root anatomy across Mexico, notably a prevalence of trait combinations favoring a reduction in axial hydraulic conductance in varieties sourced from cooler, drier highland areas. We discuss our results in the context of previously described water-banking strategies and present candidate genes that are associated with both root anatomical and environmental variation. Our strategy is a refinement of standard environmental genome-wide association analysis that is applicable whenever a training set of georeferenced phenotypic data is available.
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Affiliation(s)
- Chloee M. McLaughlin
- Intercollege Graduate Degree Program in Plant BiologyThe Pennsylvania State UniversityUniversity ParkPennsylvaniaUSA
| | - Meng Li
- Department of Plant ScienceThe Pennsylvania State UniversityUniversity ParkPennsylvaniaUSA
| | - Melanie Perryman
- Department of Plant ScienceThe Pennsylvania State UniversityUniversity ParkPennsylvaniaUSA
| | - Adrien Heymans
- Umeå Plant Science Centre, Department of Forest Genetics and Plant PhysiologySwedish University of Agricultural SciencesUmeåSweden
- Earth and Life InstituteUC LouvainLouvain‐la‐NeuveBelgium
| | - Hannah Schneider
- Department of Physiology and Cell BiologyLeibniz Institute for Plant Genetics and Crop Plant Research (IPK)SeelandGermany
| | - Jesse R. Lasky
- Department of BiologyThe Pennsylvania State UniversityUniversity ParkPennsylvaniaUSA
| | - Ruairidh J. H. Sawers
- Department of Plant ScienceThe Pennsylvania State UniversityUniversity ParkPennsylvaniaUSA
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3
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Ren W, Zhao L, Liang J, Wang L, Chen L, Li P, Liu Z, Li X, Zhang Z, Li J, He K, Zhao Z, Ali F, Mi G, Yan J, Zhang F, Chen F, Yuan L, Pan Q. Genome-wide dissection of changes in maize root system architecture during modern breeding. NATURE PLANTS 2022; 8:1408-1422. [PMID: 36396706 DOI: 10.1038/s41477-022-01274-z] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2022] [Accepted: 10/12/2022] [Indexed: 05/12/2023]
Abstract
Appropriate root system architecture (RSA) can improve maize yields in densely planted fields, but little is known about its genetic basis in maize. Here we performed root phenotyping of 14,301 field-grown plants from an association mapping panel to study the genetic architecture of maize RSA. A genome-wide association study identified 81 high-confidence RSA-associated candidate genes and revealed that 28 (24.3%) of known root-related genes were selected during maize domestication and improvement. We found that modern maize breeding has selected for a steeply angled root system. Favourable alleles related to steep root system angle have continuously accumulated over the course of modern breeding, and our data pinpoint the root-related genes that have been selected in different breeding eras. We confirm that two auxin-related genes, ZmRSA3.1 and ZmRSA3.2, contribute to the regulation of root angle and depth in maize. Our genome-wide identification of RSA-associated genes provides new strategies and genetic resources for breeding maize suitable for high-density planting.
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Affiliation(s)
- Wei Ren
- College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, Key Laboratory of Plant-Soil Interactions, Ministry of Education, China Agricultural University, Beijing, China
| | - Longfei Zhao
- College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, Key Laboratory of Plant-Soil Interactions, Ministry of Education, China Agricultural University, Beijing, China
| | - Jiaxing Liang
- College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, Key Laboratory of Plant-Soil Interactions, Ministry of Education, China Agricultural University, Beijing, China
| | - Lifeng Wang
- Cereal Crops Research Institute, Henan Academy of Agricultural Sciences, Zhengzhou, China
| | - Limei Chen
- Center for Crop Functional Genomics and Molecular Breeding, China Agricultural University, Beijing, China
| | - Pengcheng Li
- College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, Key Laboratory of Plant-Soil Interactions, Ministry of Education, China Agricultural University, Beijing, China
- Key Laboratory of Plant Functional Genomics of the Ministry of Education, Yangzhou University, Yangzhou, China
| | - Zhigang Liu
- College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, Key Laboratory of Plant-Soil Interactions, Ministry of Education, China Agricultural University, Beijing, China
| | - Xiaojie Li
- College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, Key Laboratory of Plant-Soil Interactions, Ministry of Education, China Agricultural University, Beijing, China
| | - Zhihai Zhang
- College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, Key Laboratory of Plant-Soil Interactions, Ministry of Education, China Agricultural University, Beijing, China
| | - Jieping Li
- College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, Key Laboratory of Plant-Soil Interactions, Ministry of Education, China Agricultural University, Beijing, China
| | - Kunhui He
- College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, Key Laboratory of Plant-Soil Interactions, Ministry of Education, China Agricultural University, Beijing, China
| | - Zheng Zhao
- College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, Key Laboratory of Plant-Soil Interactions, Ministry of Education, China Agricultural University, Beijing, China
| | - Farhan Ali
- Cereal Crops Research Institute, Pirsabak, Nowshera, Pakistan
| | - Guohua Mi
- College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, Key Laboratory of Plant-Soil Interactions, Ministry of Education, China Agricultural University, Beijing, China
| | - Jianbing Yan
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
| | - Fusuo Zhang
- College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, Key Laboratory of Plant-Soil Interactions, Ministry of Education, China Agricultural University, Beijing, China
| | - Fanjun Chen
- College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, Key Laboratory of Plant-Soil Interactions, Ministry of Education, China Agricultural University, Beijing, China.
- Sanya Institute of China Agricultural University, Sanya, China.
| | - Lixing Yuan
- College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, Key Laboratory of Plant-Soil Interactions, Ministry of Education, China Agricultural University, Beijing, China.
- Center for Crop Functional Genomics and Molecular Breeding, China Agricultural University, Beijing, China.
| | - Qingchun Pan
- College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, Key Laboratory of Plant-Soil Interactions, Ministry of Education, China Agricultural University, Beijing, China.
- Sanya Institute of China Agricultural University, Sanya, China.
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4
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Singh J, van der Knaap E. Unintended Consequences of Plant Domestication. PLANT & CELL PHYSIOLOGY 2022; 63:1573-1583. [PMID: 35715986 DOI: 10.1093/pcp/pcac083] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Revised: 05/12/2022] [Accepted: 06/17/2022] [Indexed: 06/15/2023]
Abstract
Human selection on wild populations mostly favored a common set of plant traits during domestication. This process of direct selection also altered other independent traits that were not directly perceived or desired during crop domestication and improvement. A deeper knowledge of the inadvertent and undesirable phenotypic effects and their underlying genetic causes can help design strategies to mitigate their effects and improve genetic gain in crop plants. We review different factors explaining the negative consequences of plant domestication at the phenotypic and genomic levels. We further describe the genetic causes of undesirable effects that originate from the selection of favorable alleles during plant domestication. In addition, we propose strategies that could be useful in attenuating such effects for crop improvement. With novel -omics and genome-editing tools, it is relatively approachable to understand and manipulate the genetic and biochemical mechanisms responsible for the undesirable phenotypes in domesticated plants.
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Affiliation(s)
- Jugpreet Singh
- Center for Applied Genetic Technologies, 111 Riverbend Road, University of Georgia, Athens, GA 30602, USA
| | - Esther van der Knaap
- Center for Applied Genetic Technologies, 111 Riverbend Road, University of Georgia, Athens, GA 30602, USA
- Institute for Plant Breeding, Genetics and Genomics, 111 Riverbend Road, University of Georgia, Athens, GA 30602, USA
- Department of Horticulture, University of Georgia, Athens, GA 30602, USA
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5
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Genetic Parameters for Selected Traits of Inbred Lines of Maize (Zea mays L.). APPLIED SCIENCES-BASEL 2022. [DOI: 10.3390/app12146961] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
This paper presents an estimation of the parameters connected with the additive (a) effect, additive by additive (aa) epistatic effect, and additive by additive by additive (aaa) interaction gene effect for nine quantitative traits of maize (Zea mays L.) inbred lines. To our knowledge, this is the first report about aaa interaction of maize inbred lines. An analysis was performed on 252 lines derived from Plant Breeding Smolice Ltd. (Smolice, Poland)—Plant Breeding and Acclimatization Institute-National Research Institute Group (151 lines) and Małopolska Plant Breeding Ltd. (Kobierzyce, Poland) (101 lines). The total additive effects were significant for all studied cases. Two-way and three-way significant interactions were found in most analyzed cases with a considerable impact on phenotype. Omitting the inclusion of higher-order interactions effect in quantitative genetics may result in a substantial underestimation of additive QTL effects. Expanding models with that information may also be helpful in future homozygous line crossing projects.
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6
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Johnson JM, Kohler AR, Haus MJ, Hollender CA. Arabidopsis weep mutants exhibit narrow root angles. MICROPUBLICATION BIOLOGY 2022; 2022:10.17912/micropub.biology.000584. [PMID: 35685275 PMCID: PMC9171553 DOI: 10.17912/micropub.biology.000584] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 06/06/2022] [Accepted: 01/01/1970] [Indexed: 11/06/2022]
Abstract
Peach ( Prunus persica ) trees with a mutation in the weep gene exhibit a weeping branch phenotype. In contrast, Arabidopsis ( Arabidopsis thaliana ) weep mutants do not have a shoot architecture phenotype. A recent report revealed that barley ( Hordeum vulgare ) and wheat ( Triticum aestivum ) with mutations in EGT2, a WEEP homolog, have steeper root angles than standard varieties. We investigated the root architecture of three Arabidopsis weep mutant lines. All three lines exhibited steeper root angles and a smaller convex hull area, indicating that the total area explored by the root system is reduced. These results reveal WEEP is important for regulating lateral root angles in a dicot.
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Affiliation(s)
- Joy M Johnson
- Michigan State University Department of Horticulture
| | | | | | - Courtney A Hollender
- Michigan State University Department of Horticulture
,
Correspondence to: Courtney A Hollender (
)
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7
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Abstract
Despite their importance in supplying nutrients, root traits related to maize domestication are scarce. We used laser ablation tomography to characterize the root architecture and anatomy of 5,300-y-old maize specimens recovered from San Marcos (Tehuacán, Mexico), revealing exquisite preservation of their cellular organization. Outer cortical cells contained thick and lignified walls typical of extant maize adapted to hard soils. By contrast, the absence of seminal roots is only found in the maize ancestor, teosinte. Two genes important for seminal root development had mutations that could relate to their absence. Our results indicate that some traits related to drought adaptation were not fully present in the earliest maize from Tehuacán, providing clues to conditions prevailing during early maize cultivation. Efforts to understand the phenotypic transition that gave rise to maize from teosinte have mainly focused on the analysis of aerial organs, with little insights into possible domestication traits affecting the root system. Archeological excavations in San Marcos cave (Tehuacán, Mexico) yielded two well-preserved 5,300 to 4,970 calibrated y B.P. specimens (SM3 and SM11) corresponding to root stalks composed of at least five nodes with multiple nodal roots and, in case, a complete embryonic root system. To characterize in detail their architecture and anatomy, we used laser ablation tomography to reconstruct a three-dimensional segment of their nodal roots and a scutellar node, revealing exquisite preservation of the inner tissue and cell organization and providing reliable morphometric parameters for cellular characteristics of the stele and cortex. Whereas SM3 showed multiple cortical sclerenchyma typical of extant maize, the scutellar node of the SM11 embryonic root system completely lacked seminal roots, an attribute found in extant teosinte and in two specific maize mutants: root with undetectable meristem1 (rum1) and rootless concerning crown and seminal roots (rtcs). Ancient DNA sequences of SM10—a third San Marcos specimen of equivalent age to SM3 and SM11—revealed the presence of mutations in the transcribed sequence of both genes, offering the possibility for some of these mutations to be involved in the lack of seminal roots of the ancient specimens. Our results indicate that the root system of the earliest maize from Tehuacán resembled teosinte in traits important for maize drought adaptation.
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8
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Kunej U, Jakše J, Radišek S, Štajner N. Identification and Characterization of Verticillium nonalfalfae-Responsive MicroRNAs in the Roots of Resistant and Susceptible Hop Cultivars. PLANTS (BASEL, SWITZERLAND) 2021; 10:1883. [PMID: 34579416 PMCID: PMC8471970 DOI: 10.3390/plants10091883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 08/30/2021] [Accepted: 09/09/2021] [Indexed: 11/27/2022]
Abstract
MicroRNAs are 21- to 24-nucleotide-long, non-coding RNA molecules that regulate gene expression at the post-transcriptional level. They can modulate various biological processes, including plant response and resistance to fungal pathogens. Hops are grown for use in the brewing industry and, recently, also for the pharmaceutical industry. Severe Verticillium wilt caused by the phytopathogenic fungus Verticillium nonalfalfae, is the main factor in yield loss in many crops, including hops (Humulus lupulus L.). In our study, we identified 56 known and 43 novel miRNAs and their expression patterns in the roots of susceptible and resistant hop cultivars after inoculation with V. nonalfalfae. In response to inoculation with V. nonalfalfae, we found five known and two novel miRNAs that are differentially expressed in the susceptible cultivar and six known miRNAs in the resistant cultivar. Differentially expressed miRNAs target 49 transcripts involved in protein localization and pigment synthesis in the susceptible cultivar, whereas they are involved in transcription factor regulation and hormone signalling in the resistant cultivar. The results of our study suggest that the susceptible and resistant hop cultivars respond differently to V. nonalfalfae inoculation at the miRNA level and that miRNAs may contribute to the successful defence of the resistant cultivar.
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Affiliation(s)
- Urban Kunej
- Department of Agronomy, Biotechnical Faculty, University of Ljubljana, 1000 Ljubljana, Slovenia; (U.K.); (J.J.)
| | - Jernej Jakše
- Department of Agronomy, Biotechnical Faculty, University of Ljubljana, 1000 Ljubljana, Slovenia; (U.K.); (J.J.)
| | - Sebastjan Radišek
- Plant Protection Department, Slovenian Institute of Hop Research and Brewing, 3310 Žalec, Slovenia;
| | - Nataša Štajner
- Department of Agronomy, Biotechnical Faculty, University of Ljubljana, 1000 Ljubljana, Slovenia; (U.K.); (J.J.)
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9
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Liu Y, Wang W, Yang B, Currey C, Fei SZ. Functional Analysis of the teosinte branched 1 Gene in the Tetraploid Switchgrass ( Panicum virgatum L.) by CRISPR/Cas9-Directed Mutagenesis. FRONTIERS IN PLANT SCIENCE 2020; 11:572193. [PMID: 33101338 PMCID: PMC7546813 DOI: 10.3389/fpls.2020.572193] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2020] [Accepted: 09/03/2020] [Indexed: 05/25/2023]
Abstract
Tillering is an important biomass yield component trait in switchgrass (Panicum virgatum L.). Teosinte branched 1 (tb1)/Branched 1 (BRC1) gene is a known regulator for tillering/branching in several plant species; however, its role on tillering in switchgrass remains unknown. Here, we report physiological and molecular characterization of mutants created by CRISPR/Cas9. We successfully obtained nonchimeric Pvtb1a and Pvtb1b mutants from chimeric T0 mutants using nodal culture. The biallelic Pvtb1a-Pvtb1b mutant plants produced significantly more tillers and higher fresh weight biomass than the wild-type plants. The increased tiller number in the mutant plants resulted primarily from hastened outgrowth of lower axillary buds. Increased tillers were also observed in transgene-free BC1 monoallelic mutants for either Pvtb1a-Pvtb1b or Pvtb1b gene alone, suggesting Pvtb1 genes act in a dosage-dependent manner. Transcriptome analysis showed 831 genes were differentially expressed in the Pvtb1a-Pvtb1b double knockdown mutant. Gene Ontology analysis revealed downregulation of Pvtb1 genes affected multiple biological processes, including transcription, flower development, cell differentiation, and stress/defense responses in edited plants. This study demonstrates that Pvtb1 genes play a pivotal role in tiller production as a negative regulator in switchgrass and provides opportunities for further research aiming to elucidate the molecular pathway regulating tillering in switchgrass.
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Affiliation(s)
- Yang Liu
- Interdepartmental Program in Plant Biology, Iowa State University, Ames, IA, United States
- Department of Horticulture, Iowa State University, Ames, IA, United States
| | - Weiling Wang
- Department of Horticulture, Iowa State University, Ames, IA, United States
- Innovation Center of Rice Cultivation Technology in Yangtze River Valley, Ministry of Agriculture/Key Laboratory of Crop Genetics and Physiology of Jiangsu Province, Yangzhou University, Yangzhou, China
| | - Bing Yang
- Christopher S. Bond Life Sciences Center, Division of Plant Sciences, University of Missouri, Columbia, MO, United States
- Donald Danforth Plant Science Center, St. Louis, MO, United States
| | - Christopher Currey
- Interdepartmental Program in Plant Biology, Iowa State University, Ames, IA, United States
| | - Shui-zhang Fei
- Interdepartmental Program in Plant Biology, Iowa State University, Ames, IA, United States
- Department of Horticulture, Iowa State University, Ames, IA, United States
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10
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Brisson VL, Schmidt JE, Northen TR, Vogel JP, Gaudin ACM. Impacts of Maize Domestication and Breeding on Rhizosphere Microbial Community Recruitment from a Nutrient Depleted Agricultural Soil. Sci Rep 2019; 9:15611. [PMID: 31666614 PMCID: PMC6821752 DOI: 10.1038/s41598-019-52148-y] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Accepted: 10/13/2019] [Indexed: 11/09/2022] Open
Abstract
Maize domestication and breeding have resulted in drastic and well documented changes in aboveground traits, but belowground effects on root system functioning and rhizosphere microbial communities remain poorly understood, despite their critical importance for nutrient and water acquisition. We investigated the rhizosphere microbial community composition and structure of ten Zea mays accessions along an evolutionary transect (two teosinte, three inbred maize lines, and five modern maize hybrids) grown in nutrient depleted soil from a low input agricultural system. Microbial community analysis revealed significant differences in community composition between soil compartments (proximal vs. distal rhizosphere) and between plant genetic groups (teosinte, inbred, and modern hybrid). Only a small portion of the microbial community was differentially selected across plant genetic groups: 3.7% of prokaryotic community members and 4.9% of fungal community members were significantly associated with a specific plant genetic group. Indicator species analysis showed the greatest differentiation between modern hybrids and the other two plant genetic groups. Co-occurrence network analysis revealed that microbial co-occurrence patterns of the inbred maize lines’ rhizosphere were significantly more similar to those of the teosintes than to the modern hybrids. Our results suggest that advances in hybrid development significantly impacted rhizosphere microbial communities and network assembly.
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Affiliation(s)
- Vanessa L Brisson
- Lawrence Berkeley National Laboratory, Berkeley, CA, USA. .,The DOE Joint Genome Institute, Walnut Creek, CA, USA. .,Lawrence Livermore National Laboratory, Livermore, CA, USA.
| | - Jennifer E Schmidt
- Department of Plant Sciences, University of California at Davis, Davis, CA, USA
| | - Trent R Northen
- Lawrence Berkeley National Laboratory, Berkeley, CA, USA.,The DOE Joint Genome Institute, Walnut Creek, CA, USA
| | - John P Vogel
- Lawrence Berkeley National Laboratory, Berkeley, CA, USA.,The DOE Joint Genome Institute, Walnut Creek, CA, USA.,Department of Plant and Microbial Biology, University of California Berkeley, Berkeley, CA, USA
| | - Amélie C M Gaudin
- Lawrence Berkeley National Laboratory, Berkeley, CA, USA.,Department of Plant Sciences, University of California at Davis, Davis, CA, USA
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11
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O'Brien AM, Sawers RJ, Strauss SY, Ross‐Ibarra J. Adaptive phenotypic divergence in an annual grass differs across biotic contexts*. Evolution 2019; 73:2230-2246. [DOI: 10.1111/evo.13818] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Accepted: 06/16/2019] [Indexed: 12/20/2022]
Affiliation(s)
- Anna M. O'Brien
- Center for Population Biology University of California Davis California 95616
- Department of Plant Sciences University of California Davis California 95616
- Department of Evolution and Ecology University of California Davis California 95616
- Department of Ecology and Evolutionary Biology University of Toronto Toronto Ontario M5S 3B2 Canada
| | - Ruairidh J.H. Sawers
- Laboratorio Nacional de Genómica para la Biodiversidad (LANGEBIO) Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV‐IPN) Irapuato 36821 Guanajuato Mexico
| | - Sharon Y. Strauss
- Center for Population Biology University of California Davis California 95616
- Department of Evolution and Ecology University of California Davis California 95616
| | - Jeffrey Ross‐Ibarra
- Center for Population Biology University of California Davis California 95616
- Department of Plant Sciences University of California Davis California 95616
- Department of Evolution and Ecology University of California Davis California 95616
- Genome Center University of California Davis California 95616
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12
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Jia Z, Liu Y, Gruber BD, Neumann K, Kilian B, Graner A, von Wirén N. Genetic Dissection of Root System Architectural Traits in Spring Barley. FRONTIERS IN PLANT SCIENCE 2019; 10:400. [PMID: 31001309 PMCID: PMC6454135 DOI: 10.3389/fpls.2019.00400] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Accepted: 03/18/2019] [Indexed: 05/19/2023]
Abstract
Breeding new crop cultivars with efficient root systems carries great potential to enhance resource use efficiency and plant adaptation to unstable climates. Here, we evaluated the natural variation of root system architectural traits in a diverse spring barley association panel and conducted genome-wide association mapping to identify genomic regions associated with root traits. For six studied traits, root system depth, root spreading angle, seminal root number, total seminal root length, and average seminal root length 1.9- to 4.2-fold variations were recorded. Using a mixed linear model, 55 QTLs were identified cumulatively explaining between 12.1% of the phenotypic variance for seminal root number to 48.1% of the variance for root system depth. Three major QTLs controlling root system depth, root spreading angle and total seminal root length were found on Chr 2H (56.52 cM), Chr 3H (67.92 cM), and Chr 2H (76.20 cM) and explained 12.4%, 18.4%, and 22.2% of the phenotypic variation, respectively. Meta-analysis and allele combination analysis indicated that root system depth and root spreading angle are valuable candidate traits for improving grain yield by pyramiding of favorable alleles.
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Affiliation(s)
- Zhongtao Jia
- Molecular Plant Nutrition, Leibniz Institute of Plant Genetics and Crop Plant Research, Gatersleben, Germany
| | - Ying Liu
- Molecular Plant Nutrition, Leibniz Institute of Plant Genetics and Crop Plant Research, Gatersleben, Germany
| | - Benjamin D. Gruber
- Molecular Plant Nutrition, Leibniz Institute of Plant Genetics and Crop Plant Research, Gatersleben, Germany
| | - Kerstin Neumann
- Genome Diversity, Leibniz Institute of Plant Genetics and Crop Plant Research, Gatersleben, Germany
| | - Benjamin Kilian
- Genome Diversity, Leibniz Institute of Plant Genetics and Crop Plant Research, Gatersleben, Germany
| | - Andreas Graner
- Genome Diversity, Leibniz Institute of Plant Genetics and Crop Plant Research, Gatersleben, Germany
| | - Nicolaus von Wirén
- Molecular Plant Nutrition, Leibniz Institute of Plant Genetics and Crop Plant Research, Gatersleben, Germany
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14
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Diao Y, Zhan J, Zhao Y, Liu L, Liu P, Wei X, Ding Y, Sajjad M, Hu W, Wang P, Ge X. GhTIE1 Regulates Branching Through Modulating the Transcriptional Activity of TCPs in Cotton and Arabidopsis. FRONTIERS IN PLANT SCIENCE 2019; 10:1348. [PMID: 31719830 PMCID: PMC6827420 DOI: 10.3389/fpls.2019.01348] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Accepted: 09/27/2019] [Indexed: 05/22/2023]
Abstract
Transcription factors (TFs) and transcriptional regulators are important switches in transcriptional networks. In recent years, the transcriptional regulator TIE1 (TCP interactor containing EAR motif protein 1) was identified as a nuclear transcriptional repressor which regulates leaf development and controls branch development. However, the function and regulatory network of GhTIE1 has not been studied in cotton. Here, we demonstrated that GhTIE1 is functionally conserved in controlling shoot branching in cotton and Arabidopsis. Overexpression of GhTIE1 in Arabidopsis leads to higher bud vigor and more branches, while silencing GhTIE1 in cotton reduced bud activity and increased branching inhibition. Yeast two-hybrid (Y2H) and bimolecular fluorescence complementation (BiFC) assays showed that GhTIE1 directly interacted with subclass II TCPs (GhBRC1, GhBRC2, and GhTCP13) in vivo and in vitro. Overexpression of GhBRC1, GhBRC2, and GhTCP13 in mutant brc1-2 partially rescued the mutant phenotype and decreased the number of branches, showing that these TCPs are functionally redundant in controlling branching. A transient dual-luciferase reporter assay indicated that GhTIE1 repressed the protein activity of GhBRC1 and GhTCP13, and thereby decreased the expression of their target gene GhHB21. Gene expression level analysis in GhTIE1-overexpressed and silenced plants also proved that GhTIE1 regulated shoot branching via repressing the activity of BRC1, HB21, HB40, and HB53. Our data reveals that shoot branching can be controlled via modulation of the activity of the TIE1 and TCP proteins and provides a theoretical basis for cultivating cotton varieties with ideal plant types.
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Affiliation(s)
- Yangyang Diao
- State Key Laboratory of Cotton Biology, Institute of Cotton Research of Chinese Academy of Agricultural Sciences, Anyang, China
| | - Jingjing Zhan
- State Key Laboratory of Cotton Biology, Institute of Cotton Research of Chinese Academy of Agricultural Sciences, Anyang, China
| | - Yanyan Zhao
- State Key Laboratory of Cotton Biology, Institute of Cotton Research of Chinese Academy of Agricultural Sciences, Anyang, China
| | - Lisen Liu
- State Key Laboratory of Cotton Biology, Institute of Cotton Research of Chinese Academy of Agricultural Sciences, Anyang, China
| | - Peipei Liu
- State Key Laboratory of Cotton Biology (Hebei Base), College of Agronomy, Hebei Agricultural University, Baoding, China
| | - Xi Wei
- State Key Laboratory of Cotton Biology, Institute of Cotton Research of Chinese Academy of Agricultural Sciences, Anyang, China
| | - Yanpeng Ding
- State Key Laboratory of Cotton Biology (Hebei Base), College of Agronomy, Hebei Agricultural University, Baoding, China
| | - Muhammad Sajjad
- State Key Laboratory of Cotton Biology, Institute of Cotton Research of Chinese Academy of Agricultural Sciences, Anyang, China
| | - Wei Hu
- State Key Laboratory of Cotton Biology, Institute of Cotton Research of Chinese Academy of Agricultural Sciences, Anyang, China
| | - Peng Wang
- State Key Laboratory of Cotton Biology, Institute of Cotton Research of Chinese Academy of Agricultural Sciences, Anyang, China
| | - Xiaoyang Ge
- State Key Laboratory of Cotton Biology, Institute of Cotton Research of Chinese Academy of Agricultural Sciences, Anyang, China
- *Correspondence: Xiaoyang Ge,
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15
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Sawers RJH, Ramírez-Flores MR, Olalde-Portugal V, Paszkowski U. The impact of domestication and crop improvement on arbuscular mycorrhizal symbiosis in cereals: insights from genetics and genomics. THE NEW PHYTOLOGIST 2018; 220:1135-1140. [PMID: 29658105 DOI: 10.1111/nph.15152] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Accepted: 02/19/2018] [Indexed: 06/08/2023]
Abstract
Contents Summary 1135 I. Introduction 1135 II. Recruitment of plant metabolites and hormones as signals in AM symbiosis 1136 III. Phytohormones are regulators of AM symbiosis and targets of plant breeding 1137 IV. Variation in host response to AM symbiosis 1137 V. Outlook 1137 Acknowledgements 1139 References 1139 SUMMARY: Cereals (rice, maize, wheat, sorghum and the millets) provide over 50% of the world's caloric intake, a value that rises to > 80% in developing countries. Since domestication, cereals have been under artificial selection, largely directed towards higher yield. Throughout this process, cereals have maintained their capacity to interact with arbuscular mycorrhizal (AM) fungi, beneficial symbionts that associate with the roots of most terrestrial plants. It has been hypothesized that the shift from the wild to cultivation, and above all the last c. 50 years of intensive breeding for high-input farming systems, has reduced the capacity of the major cereal crops to gain full benefit from AM interactions. Recent studies have shed further light on the molecular basis of establishment and functioning of AM symbiosis in cereals, providing insight into where the breeding process might have had an impact. Classic phytohormones, targets of artificial selection during the generation of Green Revolution semi-dwarf varieties, have emerged as important regulators of AM symbiosis. Although there is still much to be learnt about the mechanistic basis of variation in symbiotic outcome, these advances are providing an insight into the role of arbuscular mycorrhiza in agronomic systems.
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Affiliation(s)
- Ruairidh J H Sawers
- Laboratorio Nacional de Genómica para la Biodiversidad/Unidad de Genómica Avanzada, Centro de Investigación y de Estudios Avanzados, Instituto Politécnico Nacional (CINVESTAV-IPN), Irapuato, C.P. 36821, Guanajuato, México
| | - M Rosario Ramírez-Flores
- Departamento de Biotecnología y Bioquímica, Centro de Investigación y de Estudios Avanzados (CINVESTAV-IPN), Irapuato, C.P. 36821, Guanajuato, México
| | - Víctor Olalde-Portugal
- Departamento de Biotecnología y Bioquímica, Centro de Investigación y de Estudios Avanzados (CINVESTAV-IPN), Irapuato, C.P. 36821, Guanajuato, México
| | - Uta Paszkowski
- Department of Plant Sciences, University Cambridge, Cambridge, CB2 3EA, UK
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16
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Stitzer MC, Ross-Ibarra J. Maize domestication and gene interaction. THE NEW PHYTOLOGIST 2018; 220:395-408. [PMID: 30035321 DOI: 10.1111/nph.15350] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Accepted: 06/05/2018] [Indexed: 05/24/2023]
Abstract
Contents Summary 395 I. Introduction 395 II. The genetic basis of maize domestication 396 III. The tempo of maize domestication 401 IV. Genetic interactions and selection during maize domestication 401 V. Gene networks of maize domestication alleles 404 VI. Implications of gene interactions on evolution and selection404 VII. Conclusions 405 Acknowledgements 405 References 405 SUMMARY: Domestication is a tractable system for following evolutionary change. Under domestication, wild populations respond to shifting selective pressures, resulting in adaptation to the new ecological niche of cultivation. Owing to the important role of domesticated crops in human nutrition and agriculture, the ancestry and selection pressures transforming a wild plant into a domesticate have been extensively studied. In Zea mays, morphological, genetic and genomic studies have elucidated how a wild plant, the teosinte Z. mays subsp. parviglumis, was transformed into the domesticate Z. mays subsp. mays. Five major morphological differences distinguish these two subspecies, and careful genetic dissection has pinpointed the molecular changes responsible for several of these traits. But maize domestication was a consequence of more than just five genes, and regions throughout the genome contribute. The impacts of these additional regions are contingent on genetic background, both the interactions between alleles of a single gene and among alleles of the multiple genes that modulate phenotypes. Key genetic interactions include dominance relationships, epistatic interactions and pleiotropic constraint, including how these variants are connected in gene networks. Here, we review the role of gene interactions in generating the dramatic phenotypic evolution seen in the transition from teosinte to maize.
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Affiliation(s)
- Michelle C Stitzer
- Department of Plant Sciences, University of California, Davis, Davis, CA, 95616, USA
- Center for Population Biology, University of California, Davis, Davis, CA, 95616, USA
| | - Jeffrey Ross-Ibarra
- Department of Plant Sciences, University of California, Davis, Davis, CA, 95616, USA
- Center for Population Biology, University of California, Davis, Davis, CA, 95616, USA
- Genome Center, University of California, Davis, Davis, CA, 95616, USA
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17
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Shehata HR, Dumigan C, Watts S, Raizada MN. An endophytic microbe from an unusual volcanic swamp corn seeks and inhabits root hair cells to extract rock phosphate. Sci Rep 2017; 7:13479. [PMID: 29044186 PMCID: PMC5647395 DOI: 10.1038/s41598-017-14080-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Accepted: 10/05/2017] [Indexed: 12/14/2022] Open
Abstract
In the animal microbiome, localization of microbes to specific cell types is well established, but there are few such examples within the plant microbiome which includes endophytes. Endophytes are non-pathogenic microbes that inhabit plants. Root hairs are single cells, equivalent to the nutrient-absorbing intestinal microvilli of animals, used by plants to increase the root surface area for nutrient extraction from soil including phosphorus (P). There has been significant interest in the microbiome of intestinal microvilli but less is known about the root hair microbiome. Here we describe a bacterial endophyte (3F11) from Zea nicaraguensis, a wild corn discovered in a Nicaraguan swamp above rock-P lava flowing from the San Cristobal volcano. Rock-P is insoluble and a major challenge for plants. Following seed coating and germination on insoluble-P, the endophyte colonized epidermal surfaces, ultimately colonizing root hairs intracellularly. The endophyte promoted root hair growth and secreted acids to solubilize rock-P for uptake by a larger root hair surface. The most interesting observation was that a seed-coated endophyte targeted and colonized a critical cell type, root hair cells, consistent with earlier studies. The endophyte maintained its targeting ability in two evolutionary divergent hosts, suggesting that the host recognition machinery is conserved.
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Affiliation(s)
- Hanan R Shehata
- Department of Plant Agriculture, University of Guelph, Guelph, ON, N1G 2W1, Canada
- Department of Microbiology, School of Pharmacy, Mansoura University, Mansoura, Egypt
| | - Christopher Dumigan
- Department of Plant Agriculture, University of Guelph, Guelph, ON, N1G 2W1, Canada
| | - Sophia Watts
- Department of Plant Agriculture, University of Guelph, Guelph, ON, N1G 2W1, Canada
| | - Manish N Raizada
- Department of Plant Agriculture, University of Guelph, Guelph, ON, N1G 2W1, Canada.
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18
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Rellán-Álvarez R, Lobet G, Dinneny JR. Environmental Control of Root System Biology. ANNUAL REVIEW OF PLANT BIOLOGY 2016; 67:619-42. [PMID: 26905656 DOI: 10.1146/annurev-arplant-043015-111848] [Citation(s) in RCA: 87] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The plant root system traverses one of the most complex environments on earth. Understanding how roots support plant life on land requires knowing how soil properties affect the availability of nutrients and water and how roots manipulate the soil environment to optimize acquisition of these resources. Imaging of roots in soil allows the integrated analysis and modeling of environmental interactions occurring at micro- to macroscales. Advances in phenotyping of root systems is driving innovation in cross-platform-compatible methods for data analysis. Root systems acclimate to the environment through architectural changes that act at the root-type level as well as through tissue-specific changes that affect the metabolic needs of the root and the efficiency of nutrient uptake. A molecular understanding of the signaling mechanisms that guide local and systemic signaling is providing insight into the regulatory logic of environmental responses and has identified points where crosstalk between pathways occurs.
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Affiliation(s)
- Rubén Rellán-Álvarez
- Laboratorio Nacional de Genómica para la Biodiversidad (Langebio), Unidad de Genómica Avanzada, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN), Irapuato, Guanajuato 36821, Mexico;
| | - Guillaume Lobet
- PhytoSYSTEMS, University of Liège, 4000 Liège, Belgium;
- Institut für Bio- und Geowissenschaften: Agrosphäre, Forschungszentrum Jülich, D-52425 Jülich, Germany
| | - José R Dinneny
- Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305;
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19
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Topp CN, Bray AL, Ellis NA, Liu Z. How can we harness quantitative genetic variation in crop root systems for agricultural improvement? JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2016; 58:213-25. [PMID: 26911925 DOI: 10.1111/jipb.12470] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Accepted: 02/21/2016] [Indexed: 05/20/2023]
Abstract
Root systems are a black box obscuring a comprehensive understanding of plant function, from the ecosystem scale down to the individual. In particular, a lack of knowledge about the genetic mechanisms and environmental effects that condition root system growth hinders our ability to develop the next generation of crop plants for improved agricultural productivity and sustainability. We discuss how the methods and metrics we use to quantify root systems can affect our ability to understand them, how we can bridge knowledge gaps and accelerate the derivation of structure-function relationships for roots, and why a detailed mechanistic understanding of root growth and function will be important for future agricultural gains.
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Affiliation(s)
| | - Adam L Bray
- Donald Danforth Plant Science Center, Saint Louis, Missouri 63132, USA
| | - Nathanael A Ellis
- Donald Danforth Plant Science Center, Saint Louis, Missouri 63132, USA
| | - Zhengbin Liu
- Donald Danforth Plant Science Center, Saint Louis, Missouri 63132, USA
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20
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Schmidt JE, Bowles TM, Gaudin ACM. Using Ancient Traits to Convert Soil Health into Crop Yield: Impact of Selection on Maize Root and Rhizosphere Function. FRONTIERS IN PLANT SCIENCE 2016; 7:373. [PMID: 27066028 PMCID: PMC4811947 DOI: 10.3389/fpls.2016.00373] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2016] [Accepted: 03/11/2016] [Indexed: 05/21/2023]
Abstract
The effect of domestication and modern breeding on aboveground traits in maize (Zea mays) has been well-characterized, but the impact on root systems and the rhizosphere remain unclear. The transition from wild ecosystems to modern agriculture has focused on selecting traits that yielded the largest aboveground production with increasing levels of crop management and nutrient inputs. Root morphology, anatomy, and ecophysiological processes may have been affected by the substantial environmental and genetic shifts associated with this transition. As a result, root and rhizosphere traits that allow more efficient foraging and uptake in lower synthetic input environments might have been lost. The development of modern maize has led to a shift in microbiome community composition, but questions remain as to the dynamics and drivers of this change during maize evolution and its implications for resource acquisition and agroecosystem functioning under different management practices. Better understanding of how domestication and breeding affected root and rhizosphere microbial traits could inform breeding strategies, facilitate the sourcing of favorable alleles, and open new frontiers to improve resource use efficiency through greater integration of root development and ecophysiology with agroecosystem functioning.
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Affiliation(s)
- Jennifer E. Schmidt
- Department of Plant Sciences, University of California at DavisDavis, CA, USA
| | - Timothy M. Bowles
- Department of Natural Resources and the Environment, University of New HampshireDurham, NH, USA
| | - Amélie C. M. Gaudin
- Department of Plant Sciences, University of California at DavisDavis, CA, USA
- *Correspondence: Amélie C. M. Gaudin
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21
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Goron TL, Bhosekar VK, Shearer CR, Watts S, Raizada MN. Whole plant acclimation responses by finger millet to low nitrogen stress. FRONTIERS IN PLANT SCIENCE 2015; 6:652. [PMID: 26347768 PMCID: PMC4541148 DOI: 10.3389/fpls.2015.00652] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Accepted: 08/06/2015] [Indexed: 05/05/2023]
Abstract
The small grain cereal, finger millet (FM, Eleusine coracana L. Gaertn), is valued by subsistence farmers in India and East Africa as a low-input crop. It is reported by farmers to require no added nitrogen (N), or only residual N, to produce grain. Exact mechanisms underlying the acclimation responses of FM to low N are largely unknown, both above and below ground. In particular, the responses of FM roots and root hairs to N or any other nutrient have not previously been reported. Given its low N requirement, FM also provides a rare opportunity to study long-term responses to N starvation in a cereal species. The objective of this study was to survey the shoot and root morphometric responses of FM, including root hairs, to low N stress. Plants were grown in pails in a semi-hydroponic system on clay containing extremely low background N, supplemented with N or no N. To our surprise, plants grown without deliberately added N grew to maturity, looked relatively normal and produced healthy seed heads. Plants responded to the low N treatment by decreasing shoot, root, and seed head biomass. These declines under low N were associated with decreased shoot tiller number, crown root number, total crown root length and total lateral root length, but with no consistent changes in root hair traits. Changes in tiller and crown root number appeared to coordinate the above and below ground acclimation responses to N. We discuss the remarkable ability of FM to grow to maturity without deliberately added N. The results suggest that FM should be further explored to understand this trait. Our observations are consistent with indigenous knowledge from subsistence farmers in Africa and Asia, where it is reported that this crop can survive extreme environments.
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Affiliation(s)
| | | | | | | | - Manish N. Raizada
- *Correspondence: Manish N. Raizada, Department of Plant Agriculture, University of Guelph, 50 Stone Road East, Guelph, ON N1G 2W1, Canada,
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