Exploration Of Neonicotinoid Resistance Among Cotton Aphid Aphis Gossypii And Its Amelioration

Abstract

Neonicotinoids are the most important chemical class of insecticides, owing to their high newlineefficacy against a wide range of insect pests. As the farmers are frequently using the newlineneonicotinoids against sucking insect pests, there is a possibility of development of resistance. In newlineorder to monitor the level of susceptibility in sucking pests against neonicotinoids, bioassays newlinewere conducted using the field populations collected from ten different locations of Tamil Nadu newlineviz., Aruppukottai, Coimbatore, Dindigul, Madurai, Manamadurai, Perambalur, Srivilliputtur, newlineTirunelveli, Trichy and Tuticorin against six different neonicotinoids viz., acetamiprid, newlineclothianidin, dinotefuran, imidacloprid, thiacloprid and thiamethoxam in Agricultural College newlineand Research Institute, Madurai during 2017. When compared to the susceptible population all newlinethe ten different population showed resistance against all the six neonicotinoids. The A. gossypii newlinecollected from Perambalur were found to be highly resistant to all the neonicotinoids and LC50 newlinevalues of 0.884, 0.311, 0.834, 1.718 and 0.521 ppm for acetamiprid, clothianidin, dinotefuran, newlineimidacloprid and thiacloprid, respectively. The aphid populations collected from Tuticorin also newlineexpressed high resistance against thiamethoxam with LC50 value of 2.184 ppm. Out of six newlineneonicotinoids studied the A. gossypii collected from different locations were relatively less newlineresistant to clothianidin and thiacloprid when compared to the rest of the neonicotinoids and the newlineA. gossypii populations of Tamil Nadu is slow in development resistance to clothianidin and newlinethiacloprid. Hence, clothianidin and thiacloprid shall be used as an alternative in the areas newlinerecorded with resistant aphids. These insecticides shall be recommended to use in rotation to newlineprotect their efficiency against cotton aphids. newlineThe specific activity of Glutathione S-transferase (GST), Mixed function oxidase (MFO) newlineand Carboxylesterase (CarE) was more in Perambalur population with 156.56, 40.14 and 83.50 newlinemoles min-1 mg protein-1, respectivel