Cotton leaf curl Kokhran virus in association with Chili leaf curl betasatellite infecting mungbean (Vigna radiata.) and black gram (Vigna mungo.) in Pakistan

In 2016, begomovirus-like symptoms were observed in mungbean (Vigna radiata) and black gram (Vigna mungo) in Pakistan. Symptomatic and asymptomatic leaf samples were collected and total genomic DNA was extracted. Full length begomovirus and betasatellite genomes were PCR amplified and cloned in plasmid pTZ/57RT cloning vector. The cloned molecules were subjected to Sanger sequencing. Based on Sequence Demarcation Tool, the begomovirus clone SR-3 identified in mungbean showed 94.50% highest identity with cotton leaf curl Kokhran virus-Kokhran (CLCuKoV-Ko), while the clone SR-5 isolated from black gram showed 99.7% highest identity with CLCuKoV-Ko. In phylogenetic tree analysis the identified isolates made a lower branch tree with CLCuKoV-Ko. The betasatellite clone SR-79 isolated from black gram showed 97% similarity with chili leaf curl betasatellite (ChLCB) and the betasatellite clone SR-93 isolated from mungbean showed 97.7% similarity with ChLCB. Southern blot analysis also confirmed the presence of CLCuKoV-Ko. This is the first report of CLCuKoV-Ko associated with ChLCB infecting both mungbean and black gram in Pakistan. This presents the new combination of disease complex and increase in host range of this virus species, which shows a real threat to other crops especially legume crops in Pakistan.