Magnitude of bud blight disease of tomato caused by Peanut bud necrosis virus (PBNV) in Northern Eastern Karnataka

Abstract

The present study on magnitude and spatial distribution of bud blight disease of tomato caused by Peanut bud necrosis virus in major tomato growing area of North Eastern Karnataka through GPS approach during 2014-15, revealed that disease was found to occur at all the stages of the crop with characteristic symptoms such as necrotic rings with green or yellow hallow spots on leaves, later tip necrosis and die back. Further, presence of longitudinal brown necrotic streaks on petioles, stem and characteristic brown ring and chlorotic ring spots on green and red ripened tomatoes respectively. GPS based survey indicated that the % disease incidence varied from location to location (spatial variation), with the mean incidence ranging from 14.52 to 62.13 per cent. Among the six districts, highest incidence of 62.13 per cent was recorded in Kalaburgi district followed by Raichur, Bidar, Yadgir and Koppal with 60.35, 57.96, 45.68 and 37.13 per cent incidence, respectively and the least disease incidence of 14.52 per cent was recorded in Ballari district. The GPS maps plotted based on PDI scale (0-4) represents high risk areas of the disease in North Eastern Karnataka and higher magnitude of disease was recorded in many of the location surveyed were the tomato fields surrounded by alternate hosts of PBNV. The study signifies PBNV diagnostic symptoms and its prevalence in North Eastern Karnataka