Vol. 10, Special Issue 12 (2021)

Author(s):
Srinivasaraghavan A, KPS Kushwaha, Vijay N, Shrishti Lingwal and Ram Niwas

Abstract:
Yellow mosaic disease of legumes is known to be caused by four distinct viruses in India, together known as Legume Yellow Mosaic Viruses (LYMV’s). There is a lack of information regarding prevalence, distribution and identity of LYMVs on different legumes in tarai region of India. Present study was carried out in northwestern tarai region of Uttarakhand and adjoining districts of Uttar Pradesh. A roving survey was conducted for over two seasons during 2013 and 2014 to record the disease incidence, severity, vector population etc. The identity of the LYMV was confirmed by subjecting symptomatic samples PCR amplification using specific primer for each LYMV. The coat protein gene was sequenced for representative isolate from each host for phylogenetic analysis. Among the four LYMV’s, only bipartite Mungbean Yellow Mosaic India Virus (MYMIV) was found infecting majority of the Kharif legumes viz., mungbean, urdbean, soybean, pigeon pea and dolichos bean in the region. Among the various weeds suspected, only Gomphrena sessilis with yellowing and vein clearing symptoms was found to have natural infection of MYMIV. Phylogenetic analysis revealed that, all the isolates originating from different locations of tarai region found to have maximum similarity despite being associated with different hosts. Rigorous survey of mungbean and urdbean fields over 70 villages revealed that, the incidence of yellow mosaic disease ranged from 4.30 to 31.20 during 2013 and 4.20 to 31.60 during 2014. The data also revealed that the prevalence of the disease was more in U.S. Nagar during both the years (15.40 and 15.18 during 2013 and 2014 respectively).