Effect of polymer coating and thiamethoxam seed treatment of mung bean on incidence of flea beetle.

摘要

A study was conducted during kharif 2003 in Karnal, Haryana, India to evaluate the effect of pre-sowing treatment with thiamethoxam 70 WS (0, 5, 10 and 20 g a.i./kg seed) and a seed coating polymer (DiscoAg, 0 and 30 ml/kg seed), alone or in combination, on the incidence of the flea beetle, Phyllotreta sp., on mungbean cv. Pusa vishal. Both polymer and thiamethoxam treatments had no adverse effect on the mungbean stand. Polymer coating alone was not able to mitigate the flea beetle incidence as polymer-treated plants showed 36.4% leaf damage compared with 37.4% leaf damage in untreated plants. In contrast, the insecticide offered a high level of protection from flea beetles, as the leaf damage ranged from 4.9 to 5.4% in thiamethoxam-treated plants compared with 65.4% in untreated plants. Moreover, the effect of the insecticide was apparent up to 4 weeks after sowing. The least flea beetle damage was recorded in the treatment with thiamethoxam at 10 g a.i./kg seed after 2 weeks of sowing, which was at par with thiamethoxam at 5 and 20 g a.i./kg seed..