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Title: Molecular insight into cotton leaf curl geminivirus disease resistance in cultivated cotton ( Gossypium hirsutum )
Summary

Cultivated cotton (Gossypium hirsutum) is the most important fibre crop in the world. Cotton leaf curl disease (CLCuD) is the major limiting factor and a threat to textile industry in India and Pakistan. All the local cotton cultivars exhibit moderate to no resistance againstCLCuD. In this study, we evaluated an exotic cotton accession Mac7 as a resistance source toCLCuD by challenging it with viruliferous whiteflies and performingqPCRto evaluate the presence/absence and relative titre ofCLCuD‐associated geminiviruses/betasatellites. The results indicated that replication of pathogenicity determinant betasatellite is significantly attenuated in Mac7 and probably responsible for resistance phenotype. Afterwards, to decipher the genetic basis ofCLCuD resistance in Mac7, we performedRNAsequencing onCLCuD‐infested Mac7 and validatedRNA‐Seq data withqPCRon 24 independent genes. We performed co‐expression network and pathway analysis for regulation of geminivirus/betasatellite‐interacting genes. We identified nine novel modules with 52 hubs of highly connected genes in network topology within the co‐expression network. Analysis of these hubs indicated the differential regulation of auxin stimulus and cellular localization pathways in response toCLCuD. We also analysed the differential regulation of geminivirus/betasatellite‐interacting genes in Mac7. We further performed the functional validation of selected candidate genes via virus‐induced gene silencing (VIGS). Finally, we evaluated the genomic context of resistance responsive genes and found that these genes are not specific to A or D sub‐genomes ofG. hirsutum. These results have important implications in understandingCLCuD resistance mechanism and developing a durable resistance in cultivated cotton.

 
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NSF-PAR ID:
10458743
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
Plant Biotechnology Journal
Volume:
18
Issue:
3
ISSN:
1467-7644
Page Range / eLocation ID:
p. 691-706
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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