Co-existence of Mungbean yellow mosaic India virus with Cowpea mild mottle virus on soybean (Glycine max.) in North-East India

Abstract Soybean (Glycine max. L.) plants with virus-like systemic mosaic and mottling symptoms were observed in both experimental and commercial fields in Assam State, India. Begomo and Carlaviruses are the most destructive viruses infecting legume crops in India. A diagnostic survey was carried out to assess the prevalence of major viruses in soybean growing tracts of Assam and North-East India. Infected plants showing severe mosaic, mottling, and crinkling of leaves were collected. Molecular indexing was performed using reverse transcription polymerase chain reaction (RT-PCR) with a coat protein gene-specific primer of Begomovirus (Mungbean yellow mosaic virus) and a Carlavirus degenerate primer corresponding to the coat protein gene. Apparently, amplifications were seen for both Begomovirus and Carlavirus infections alone and in combination. According to the sequence analysis, the combination infections in soybean are caused by the Mungbean yellow mosaic virus (MYMIV) and the Cowpea mild mottle virus (CPMMV). This is the first molecular report of the co-existence of the Mungbean yellow mosaic India virus strain and the Cowpea mild mottle Carlavirus on soybean in N.E. India and India.