Transmission, detection and management of yellow mosaic virus in polebean (Phaseolus vulgaris L.).

摘要

Yellow mosaic of polebean (Phaseolus vulgaris) is widely prevalent in all the seasons in and around Bengaluru. The infected plants develop partial or complete brilliant golden yellow mosaic on leaves, stunted growth, less number of pods with reduced pod size. The rate of transmission of virus with 10 viruliferous whiteflies (Bemisia tabaci) was 100% at 24 h acquisition and inoculation access, and latent period for symptom expression was between 7 to 15 d after inoculation. Single whitefly per plant could transmit the disease up to 40%. The virus could be transmitted to Frenchbean, limabean, ringbean, horsegram and soybean through B. tabaci under laboratory condition. The PCR amplified product of yellow mosaic virus coat protein was approximately 500 bp, confirming it to belong to Begomovirus group. The disease could be effectively managed by integrated module viz., border crop with African tall maize, seed treatment with of imidacloprid 70% WS @ 5.0 g kg-1, use of reflective mulch, spraying of triazophos 40 EC @ 0.175% at 30 d after sowing (DAS) and with thiomethoxam 25WDG @ 0.05% at 45 DAS. The integrated module resulted in reduced disease incidence (7.4%) and whitefly count (1.0), highest yield of 32.2 t ha-1 with cost: benefit ratio of 1:3.17 compared to untreated control recording mean incidence of 33.0%, white fly count 4.73 and 9.70 t ha-1 yield.