Field population of Spodoptera litura from tomato ( resistant to the majority of the conventional insecticide molecules) were subjected to the in vivo toxicity of spinetoram 12 SC to assess whether cross resistance exists or not. Untreated larvae of both field and laboratory strains showed no mortality during 48 hours of feeding. After 48 hours of feeding on spinetoram 12 SC treated leaves, LC50s of field larvae were 0.28, 0.93, 3.71 and 7.11 ppm for the 2nd, 3rd, 4th and 5th instars of S. litura respectively. However, in the laboratory strain these values were 1.12, 5.86, 36.72 and 91.55 ppm for 2nd, 3rd, 4th and 5th instars of S. litura respectively. Resistance ratio was 0.25, 0.16, 0.10 and 0.08 for the 2nd instar up to the 5th instar of S. litura.

In this experiment a new insecticide molecule, spinetoram 12 SC was taken up to evaluate its antifeedant and repellent activity in laboratory and efficacy in the field with different mode of application against termite control. Laboratory experiments were conducted in Insectary, Agricultural College and Research Institute, Madurai. Field experiments were laid out in Randomized Block Design at farmer's field located in Mandhikanmai village, Kalayarkoil Block, Sivagangai district during 2014-2015 and to study the effect of sett treatment and soil drenching of spinetoram 12 SC with variety CO 86032. At the time of planting, sugarcane setts were treated with various doses of spinetoram 12 SC (90, 120, 150 and 180 g a.i./ha) and covered with soil. After planting in 35 days old sugarcane soil drenching treatment was also effected with the same dose of sett treatment. Imidacloprid 20 SL, Rynaxypyr 20 SC and chlorpyrifos 20 EC were standard checks. The cumulative mean food consumption was minimum 0.71 g, 0.78 g, 1.02 g, 1.23 g, 1.44 g and 1.56 g in various concentrations of spinetoram viz., 360, 300, 240, 180, 120 and 60 ppm, respectively. The highest mean per cent repellent action was noticed in spinetoram 360 ppm and 300 ppm (93.4 and 91.2%, respectively) at 12 HAT. Field experiments were inferred that spinetoram 12 SC 180 and 150 g a.i./ha were significantly effective in minimizing number of termite colony per plot, number of termites per colony and per cent sett damage in both sett treatment and soil drenching methods.

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