author(s)
Md. Jahangir Alam and Gopal Das

abstract
Buprofezin (Award 40 SC), a chitin synthesis inhibitor (CSI) has been evaluated on the mortality of brown planthopper in the laboratory condition of Department of Entomology, Bangladesh Agricultural University, during the period from April to August, 2014. The mortality was observed using three concentrations viz. 100, 200 and 300 ppm with different application methods like topical, leaf-dip and combination method. The mortality data was observed at 1, 3, 5 and 7 days after treatment (DAT) application. Buprofezin was found to be highly effective against BPH and the mortality was clearly dose and method dependent. The highest mortality (90.55%) was recorded from 300 ppm which was followed by 200 (83.06%) and 100 (43.47%) ppm of Buprofezin respectively. The dose, 100 ppm was found comparatively less effective than rest of the two doses. Among application methods, maximum mortality (90.55%) was found from combination method i.e. when both BPH and rice plants were treated with different concentration of Award 40SC which was followed by leaf-dip (87.32%) and topical (76.70%) application methods respectively. For all application methods, the mortality was found to be insignificant compared to control at 1 DAT but increased significantly at 2 DAT and reached to the highest level at 5 DAT which was persisted at least up to day 7.