1Department of Agricultural Entomology, TNAU, Coimbatore, 641003
2Department of Biotechnology, Agricultural College and Research Institute, TNAU, Madurai, 625104
3Department of Agricultural Entomology, Agricultural College & Research Institute, Tamil Nadu Agricultural University (TNAU), Madurai, 625104
*Email: parthasuvi@gmail.com (corresponding author)
Online published on 18 April, 2020.
Bioassays were conducted with neonicotinoids viz., acetamiprid, clothianidin, dinotefuran, imidacloprid, thiacloprid and thiamethoxam on field populations of cotton aphids collected from ten locations of Tamil Nadu. Perambalur population was found to be resistant to all six neonicotinoids with LC50 values of 0.884, 1.718, 1.535 and 0.521 ppm for acetamiprid, imidacloprid, thiamethoxam and thiacloprid, respectively. Aphids from all the locations showed resistance to thiamethoxam with LC50 values in range of 0.034 to 2.184 ppm. No resistance to clothianidin and dinotefuran was found with resistant ratios of 3.00 and 4.56-folds. Hence, clothianidin and dinotefuran could be promoted against aphids in rotation to sustain their efficacy.
Neonicotinoids, acetamiprid, imidacloprid, thiamethoxam, thiacloprid, clothianidin, dinotefuran, Aphis gossypii, leaf-dip bioassay, LC50
