Effect of Altered Date of Sowing and Evaluation of Chemicals and Botanicals on Yellow Vein Mosaic and Bemisia tabaci in Kenaf (Hibiscus cannabinus)

Research trials were conducted in Randomized complete block design (RCBD) at Agricultural Research Station, Amadalavalasa for two consecutive Kharif 2008 and 2009 seasons to study the effect of altered dates of sowing and comparative evaluation of chemicals and botanicals in control of yellow vein mosaic and its vector Bemisia tabaci in kenaf (Hibiscus cannabinus L). Normal dates of sowing on 2/6/2008 and 15/6/2009 recorded significantly lowest average whitefly population with significant reduction in yellow vein mosaic (4.48 and 17.58% respectively) and highest fibre recovery of 23.08 and 16.64 q/ha were observed at harvesting stage in respective years. Thiamethoxam (0.1g/l) spraying significantly reduced whitefly population from 2.33 to 0.63 and 5.76 to 1.36, reduced disease incidence (3.8% and 3.07%) and resulted in recovering significantly highest fibre yield of 22.50 and 23.47 q/ha in respective years. Normal date of sowing (Ist fortnight of June) and subsequent spraying with thiamethoxam (0.1g/l of water) at 50 days after sowing reduced the whitefly population, yellow vein mosaic and increased the fibre yield.