Population dynamics of leafhopper on cotton genotype and their correlation with weather parameters

Field experiment was conducted to investigate the population fluctuation of leafhopper and impact of abiotic factors on its population in Bt cotton. Incidence of leafhopper started from 24^th Standard Meteorological Week and continued throughout the crop season. It was observed that during 2017 and 2018 leafhopper population attained its peak during 33^rd and 32^nd SMW (3.46 and 2.93 nymphs/leaf) respectively. Leafhopper population was significantly and positively correlated with the morning relative humidity, evening relative humidity and minimum temperature while significantly negatively correlated with maximum temperature. Multiple regression analysis showed that various weather parameters were responsible for 58 to 63% variability in leafhopper population.