Seasonal Incidence of Leaf Hopper on Okra in Correlation with Abiotic Factors and Evaluation of Some Neonicotinoid Insecticides Against Okra Leaf Hopper

Abstract

Leaf hopper infestation was recorded during first and second week of July but its population build-up starts from third week of July (2. 51 leaf hoppers/3 leaves), the first peak population was recorded during second week of august (12. 78 leaf hoppers/3 leaves) and it reached its highest peak during first week of September and recorded maximum leaf hoppers population (16. 45 leaf hoppers/3 leaves) respectively. Maximum temperature was positively correlated (r=+0. 129) and rainfall was negatively correlated (r= - 0. 095) with a leaf hopper population. In respect of comparing the efficacy of neonicotinoid insecticides against leaf hopper population acetamiprid 20% SP@ 40 g. a. i. /ha was recorded as the most effective insecticidal treatment which recorded lowest leaf hopper population/plant (3. 01 leaf hopper/3 leaves) along with 81. 27 % protection over control which was followed by thiamethoxam and imidacloprid, dimethoate and aseptate 77. 71 %, 76. 43%, 69. 56% and 67. 10% protection over control respectively. Acetamiprid also recorded highest marketable yield (113. 35 q/ha), followed by imidacloprid (110. 54 q/ha), thiamethoxam (109. 02 q/ha).