Prameela, H. ANAVEESH, Y. B2017-09-212017-09-212016-08-08TH-11443http://krishikosh.egranth.ac.in/handle/1/5810031645Soybean yellow mosaic virus (SYMV) disease caused by a begomovirus is a major constraint in soybean cultivation in Karnataka. SYMV was successfully transmitted through whitefly (Bemisia tabaci). Hundred per cent virus transmission was obtained by using ten adult whiteflies per plant with 12 hr of acquisition access period (AAP), inoculation access period (IAP) and incubation period. One week old soybean plants were susceptible for SYMV infection. SYMV was successfully transmitted to soybean, horse gram, french bean, pole bean, lima bean, green gram and rice bean. The virus was detected by polymerase chain reaction (PCR) technique using viral coat protein (CP) and movement protein (MP) gene specific primers. PCR product of 1000 and 900 bp sized corresponding to CP and MP genes of the virus were amplified from total DNA obtained from SYMV infected leaf tissue. The nucleotide sequences of the CP and MP genes showed maximum nucleotide identity of 98 per cent and 99 per cent respectively with horse gram yellow mosaic virus (HgYMV) isolates infecting french bean and lima bean. Phylogenetic analysis of the sequences of CP and MP genes of SYMV revealed that virus isolate (GKVK) clustered with HgYMV infecting french bean and lima bean isolates of Bengaluru, which indicate that the virus causing SYMV disease is a strain of HgYMV. Out of forty three genotypes of soybean screened for SYMV under glass house condition, eleven genotypes viz., KDS-378, RKS-118, Bragg, DS-2706, DSb-25, Dsb-23, MAUS-2, DSb-21, DS-2708, DS-2006 and DS-2707 were found moderately resistance to SYMV.ennullThesis