2024, Vol. 7, Special Issue 9

author(s)
Jyothirmai Madhavi K, Lal Ahamed M and Prasadarao RDVJ

abstract
In the present study, thrip transmission patterns of Peanut bud necrosis virus (PBNV) and Tobacco streak virus (TSV) isolates of Blackgram and greengram were studied since both the viruses cause similar necrotic symptoms and are transmitted by thrips, the method of transmission and the virus vector relationship vary and hence need different approaches of management practices. Transmission tests with laboratory reared cultures of T. palmi, F. schultzei and S. dorsalis indicated that only T. palmi could transmit PBNV-BG and PBNV-GG to an extent 66.6% and 70% in blackgram cv. LBG-20 50% and 66.6%in greengram cv. K-851 and 60% and 87.5% in cowpea cv. C-152, respectively. F. schultzei and S. dorsalis did not transmit the virus to the test plants. Pollen from both DAC-ELISA tested TSV positive parthenium plants, collected from field (natural infection) and glasshouse (mechanically inoculated with TSV-BG and TSV-GG) produced symptoms typical of TSV on assay host, cowpea cv.C-152 indicating the presence of the virus in the pollen. The results of the thrip assisted pollen transmission experiments with TSV infective pollen showed that TSV-BG, TSV-GG were transmitted by all the four thrip species tested. All ’thrips only’ which were fed on TSV infected leaves and ‘pollen only’ control seedlings remained healthy. Varied percent transmission was observed in blackgram cv. LBG-20, greengram cv. K-851, cowpea cv.C-152, groundnut cv. JL-24, and sunflower cv.PAC-36 with TSV-BG and TSV-GG. All the four thrip species have showed transmissions to all test plants. All test plants that expressed symptoms were positive in DAC-ELISA tests confirming the transmission of TSV.