ABSTRACT
BACKGROUND: Mungbean yellow mosaic India virus (MYMIV) is a representative of the genus begomovirus/Begomoviridae, which is prevalent in the northern part of Indian subcontinent causing yellow mosaic disease (YMD). This virus is rapidly evolving and breaking the resistance in the advanced lines causing huge economic losses in the pulse production. In this context, the present investigation on characterization of the causal organism of YMD was undertaken METHODS AND RESULTS: A novel recombinant isolate (YMV-BG-BPT) causing YMD was identified from blackgram in Andhra Pradesh, southern peninsular region of India. The association of a bipartite begomovirus with the disease was done by sequence analyses of the cloned full-length genome. The full length genome sequences were submitted in NCBI GenBank with accession numbers MZ235792 (DNA-A) and MZ356197 (DNA-B). The sequence analysis of DNA-A of YMV-BG-BPT showed maximum of 99.12% similarity at nucleotide level with Mungbean yellow mosaic India virus (MYMIV) isolate reported from Tamil Nadu (KC911719), India which is also confirmed by clustering pattern in phylogenic analysis and DNA-B showed 95.79% with Mungbean yellow mosaic virus (MYMV) isolate reported from Tamil Nadu (KP319016) and 95.05% with MYMIV isolate reported from Karnataka (MT027037). The huge variation in DNA-B lead us to suspect a recombination in DNA-B, where a recombination event in the CR, region coding for nuclear shuttle protein and movement protein of DNA B was detected in which MYMV-BG-AP-IND (KF928962) and MYMIV-GG-CH-IND (MN020536) have been identified as major and minor parents, respectively. CONCLUSION: Overall, the present study revealed occurrence of MYMIV with recombinant DNA B component in southern peneinsular India.
Subject(s)
Begomovirus , Begomovirus/genetics , DNA, Recombinant , DNA, Viral/genetics , India , Plant DiseasesABSTRACT
Mungbean yellow mosaic India virus (MYMIV) is one of the most serious commonly occurring yellow mosaic virus (YMV's) group in majority of the pulses especially black gram and green gram in southern India compared to previously reported mungbean yellow mosaic virus. In January 2020 Desmodium laxiflorum and Abelmoscus moschatus showing mosaic symptoms and vein yellowing were collected from Guntur and Prakasam districts respectively in Andhra Pradesh. PCR analysis using MYMIV and betasatellite specific primers gave desired expected amplification from the infected samples of A. moschatus (YMV-ABEL) whereas only MYMIV specific amplification was obtained in D. laxiflorum (YMV-DES). However, no PCR amplification was obtained in respective healthy leaf samples of both plants. Sequence analysis showed that the CP sequence of YMV-ABEL and YMV-DES showed a similarity of 99.19% with MYMIV (KP677496) and 99.75% with MYMIV (JN181003) respectively. The full-length betasatellite (1356 bp) showed highest identity of 90% with bhendi yellow vein mosaic betasatellite (BYVMB) (GU111977). Phylogenetic analysis clustered the test isolates with south Indian isolates of MYMIV whereas the betasatellite sequence clustered with various isolates of BYVMB, tomato leaf curl New Delhi virus betasatellite and okra leaf curl betasatellite reported from India and Pakistan. To the best of our knowledge, this is the first report of a MYMIV in D. laxiflorum and A. moschatus and MYMIV betasatellite complex in A. moschatus.
