Assessment of cross-resistance in South American tomato moth, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae)

Abstract

Laboratory experiments were carried out to assess the development of cross resistance in selected resistant populations of South American tomato moth, Tuta absoluta. Insecticidal bioassays were carried for the different field population (G1) viz., Bangalore, Madurai, Salem and Kolar to assess the resistance status. The resistance population from the bioassay were further subjected to different insecticides (flubendiamide39.35SC, indoxacarb14.5SC, cyantraniliprole10.25SC, emamectin benzoate 5SG, spinosad 45SC and spinetoram11.1SC) to determine development ofcross resistance if any. From the study, flubendiamide resistance Bangalore population showed positive cross resistance to cyantraniliprole and spinosad. Cyantraniliprole resistance population from Madurai and Salem showed cross resistance to indoxacarb, flubendiamide and emamectin benzoate, and Kolar indoxacarb population to flubendiamide, cyantraniliprole and emamectin benzoate. The result from the present study thus suggests proper rotation of the insecticides with different modes of action to prevent resistance development in T. absoluta.