author(s)
Rosevellina Mohanta, Dr. Ranjan Nath, Nitish Kumar Jena and Abinash Mishra

abstract
A field experiment was conducted at Agricultural Farm of Palli-Siksha Bhavan (Institute of Agriculture), Visva-Bharati, Sriniketan, West Bengal during Kharif season, 2018. The present study was initiated with a view to gather some information regarding effect of different dates of sowing and weather parameters on vector whitefly and disease incidence of yellow vein mosaic disease in okra (Abelmoschus esculentus L. Moench) in Birbhum district. Out of five different dates of sowing highest yellow vein disease incidence was recorded in 3^rd date of sowing (11.64) PDI as well as highest vector population 4.75 whiteflies/plant, followed by 2^nd date of sowing 9.82 PDI and 3.55 whiteflies/plant, 4^th date of sowing 7.38 PDI and 3.55 whiteflies/plant. Lowest PDI was observed in 5^th date of sowing 3.38 and 2.35whiteflies/plant followed by 1^st date of sowing 4.99 and 2.95 whiteflies/plant. At last day of observation (90DAS), 5^th and 1^st dates of sowing were found most effective having lowest PDI 12.65 & 15.31 and 3.45 & 3.60 whiteflies/plant respectively. Third date of sowing recorded significantly highest YVMD incidence 24.12 and 5.90 whiteflies/plant. Among all the treatments, 5^th DOS recorded significantly higher yield (65.49q/ha) followed by 1^st DOS (53.67q/ha), 4^th DOS (45.4q/ha), 2^nd DOS (43.92q/ha). While lowest yield (37.25q/ha) was recorded in 3^rd DOS.