Location: Genomics and Bioinformatics ResearchTitle: Frequent occurrence of tomato leaf curl New Delhi virus in cotton leaf curl disease affected cotton in Pakistan
|ZAIDI, SYED - National Institute Of Biotechnology And Genetic Engineering (NIBGE)|
|SHAFIQ, MUHAMMAD - National Institute Of Biotechnology And Genetic Engineering (NIBGE)|
|AMIN, IMRAN - National Institute Of Biotechnology And Genetic Engineering (NIBGE)|
|BRIDDON, ROB - National Institute Of Biotechnology And Genetic Engineering (NIBGE)|
|MANSOOR, SHAHID - National Institute Of Biotechnology And Genetic Engineering (NIBGE)|
Submitted to: PLoS ONE
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/29/2016
Publication Date: 5/23/2016
Citation: Zaidi, S.S., Shafiq, M., Amin, I., Scheffler, B.E., Scheffler, J.A., Briddon, R.W., Mansoor, S. 2016. Frequent occurrence of tomato leaf curl New Delhi virus in cotton leaf curl disease affected cotton in Pakistan. PLoS One. doi:10.1371/journal.pone.0155520.
Interpretive Summary: Cotton leaf curl disease (CLCuD) (associated with cotton leaf curl virus) is a serious threat to cotton production in the Indian subcontinent. Already the Burewala strain is having a severe negative impact on cotton production in India and Pakistan. The USDA has classified this virus as one of the top twenty threats to USA agriculture. In this study, plant samples from the major cotton producing area of Pakistan were collected. The samples were examined at the DNA level to detect and classify any viruses in the samples. In the past, CLCuD was predominately associated with the Burewala strain but in this study many of the samples also contained Tomato leaf curl New Delhi virus and associated Multan cotton leaf curl virus alpha and beta satellites. That plants showing CLCuD symptoms can have both viruses and their associated satellites. Anytime related viruses are together there is the opportunity for exchange of genes and the creation of new novel viruses. This finding represents a new challenge for the development and maintenance of cotton varieties resistant to CLCuD.
Technical Abstract: Cotton leaf curl disease (CLCuD) in the Indian subcontinent is associated with several distinct monopartite begomoviruses and DNA satellites. However, only a single begomovirus was associated with breakdown of resistance against CLCuD in previously resistant cotton varieties. The monopartite begomovirus complex in recently collected samples consists of the Burewala strain of Cotton leaf curl Kokhran virus (CLCuKoV), previously shown to be associated with resistance breakdown, where all sequenced clones lacking a full-length transcriptional activator protein (TrAP). It was also found that the majority of recent samples also contained Tomato leaf curl New Delhi virus (ToLCNDV). The satellites associated with this disease complex are Cotton leaf curl Multan alphasatellite and Cotton leaf curl Multan betasatellite (CLCuMB). Real-time PCR quantitative estimation of begomovirus and CLCuMB showed that the levels of betasatellite were approximately double that of begomovirus DNA. The levels of DNA-B accumulated in cotton were lower than DNA-A and betasatellite but were equal to the levels of DNA-B in field infected tomato samples. Our results indicate that the CLCuD complex now consists of both monopartite and bipartite begomoviruses and their associated satellites. These results have important implications on our efforts in generating resistance against the disease complex in cotton.