Department of Entomology, College of Agriculture G B Pant university of Agriculture and Technology, Pantnagar-263145
* Correspondence: Krish Vigyan Kendra, P G College, Ghazipur, UP
Online published on 15 October, 2011.
The F1 progeny of T. castaneum samples collected from four urain markets of India showed high resistance ratio io deltamethrin, highest from Ludhiana (9.55) followed by Kanpur (7.57), Varanasi (6.36) and lowest from Hyderabad (5.23). Similar trend in resistance was observed for chlorpyriphos-methyl ranging from 8.46 fold from Ludhiana to 2.05 fold from Hyderabad. This ratio for Varanasi and Kanpur were comparable being 5.20 and 5.33 fold, resppctively. Strikingly, very high resistance (28.4) was recorded to fenvalerate from Ludhiana with not much from other three locations (<1.7 fold). The results suggested lower to medium resistance in all insect samples to deltamethrin and chlorpyriphos methyl, the highest values being recorded from Ludhiana for all the three insecticides.
Toxicity, Tribolium castaneum, insecticide desistasce
