Evaluation of thiamethoxam 70% WS as seed treatment against early sucking pests of tomato
The present investigation was carried out at Vegetable Research Centre, G. B. Pant University of Agriculture and Technology, Pantnagar, Uttarakhand during the 2013 and 2014 to evaluate the effectiveness of thiamethoxam, used as seed treatment against the sucking insects of tomato. The seed treatment with thiamethoxam protected tomato seedlings from aphids and thrips at the early season from the onset of seed planting. There was a fast initial effect against the pests then gradually decreased to reach a moderate effect. Data revealed that Thiamethoxam 70% WS @ 4.2 g a.i./kg of seed showed the significant pest reduction followed by Thiamethoxam 70% WS @ 3.85 g a.i./kg of seed. Highest yield was recorded by Thiamethoxam 70% WS @ 4.2 g a.i./kg of seed (28.25 t/ha) closely followed by Thiamethoxam 70% WS @ 3.85 g a.i./kg of seed (25.00 t/ha) as compared to untreated check (20.91t/ha). Percent increase in yield over control was highest (35.10%) in Thiamethoxam 70% WS @ 4.2 g a.i./kg of seed followed by Thiamethoxam 70% WS @ 3.85 g a.i./kg of seed (19.56%). The percent reductions of predators by Thiamethoxam, used as seed treatment, in both the seasons ranged from 1.65- 2.58% which was very minimum. Hence, it was concluded that the seed treatment of tomato with Thiamethoxam 70% WS @ 4.20 g a.i/kg of seed reduced the early season insect-pests (aphid and thrips) and had very less effect of natural enemies population ascompared to control and also increased the fruit yield significantly than other treatments.