Related Experiment Video
Updated: Mar 5, 2026
Bioassays for Monitoring Insecticide Resistance
Published on: December 30, 2010
Relative Susceptibility of Phyllocnistis citrella (Lepidoptera: Gracillariidae) to Commonly Used Insecticides in
Anjitha George1, C N Rao2, Sonali Ghike3
1Scientist, Entomology, ICAR-Central Citrus Research Institute, Nagpur 440033, Maharashtra, India (anjithakitty@gmail.com).
Abstract:
Foliar application of insecticides has been the most commonly followed practice to manage Phyllocnistis citrella Stainton in nurseries and flush leaves in citrus groves. Leaf dip bioassays were conducted against insecticides, viz., acephate 75SP, dimethoate 30EC, abamectin 1.9EC, fenvalerate 20EC, imidacloprid 17.8SL, and thiamethoxam 25WG, and were tested against P. citrella larvae for their susceptibility. Among six insecticides tested on second-instar P. citrella larvae collected from Nagpur mandarin/acid lime cultivars during 2013-2016, abamectin was the most toxic insecticide for the initial year (LC50 values ranged from 20.99 to 49.00 ppm), while dimethoate (LC50 of 36.57-160.95 ppm) and thiamethoxam (39.90-71.96 ppm) were consistently effective against P. citrella larvae for the rest of the period. Resistance ratio (RR) values calculated based on the baseline susceptible culture, viz., abamectin (1.24-2.33), acephate (1.03-2.31), fenvalerate (1.54-3.45), dimethoate(1.28-5.63), imidacloprid (1.29-8.64), and thiamethoxam (1.05-1.80), indicated that the current RR values were in low levels (RR < 10).
