Vol. 10, Issue 11 (2021)

Author(s):
Y Rajasekhar, B Swathi, N Hari Satyanarayana, P Amarajyothi and PV Padmavathi

Abstract:
Field trials were conducted at Agricultural Research Station, Amadalavalasa for six consecutive years during Kharif2015-16, 2016-17, 2017-18, 2018-19, 2019-20 and 2020-21 to assess the seasonal incidence of sucking pests and semiloopers in mesta crop. Insect pests, mealybugs and semiloopers were the dominant pests of Mesta Cropas their activity lasted throughout the crop growth period with peak population levels (26.67% incidence and 43.33% leaf damage, respectively) observed at 37^th and 26^th standard weeks, respectively. The activity of aphids was observed from 28^thstandard week attaining peak (8.05 no./plant) during 34^thstandard week. The incidence of whitefly and leafhopper continued throughout the crop growth period with whitefly had two peaks at 28^th standard week (0.70 no./ plant) and38^th standard week (0.78 no./ plant) and leafhoppers attained its high incidence (0.72 no./plant) during 26^th standard week. Among the various weather parameters, maximum temperature exerted significant positive influence on leafhoppers (r = 0.589**)and semiloopers (r= 0.638**) and aphid population showed significant positive association (r= 0.484*) with minimum temperature. Morning relative humidity had a significant positive influence on the leafhopper (r= 0.454*) and mealybug population (r= 0.731). Both evening relative humidity and rainfall exerted positive influence on mealybug, which is significant. The multiple linear regression analysis indicated that the total influence of all the weather variables viz., maximum and minimum temperatures, morning and evening relative humidities, and rainfall accounted for 55.3, 66.0, 74.3, 72.8and 56.9per cent variation in aphid, whitefly leafhopper, mealybug and semilooper populations, respectively.