Field efficacy trial of 24% wettable powder combined with carbaryl and pymetrozine against rice plant hopper

From 2009 to 2010,the field efficacy trials of 24% wettable powder combined with carbaryl and pymetrozine on rice plant hopper were conducted in Panyu,Guangzhou.The result indicated that 24% wettable powder combined with carbaryl and pymetrozine,at the dose of 110,140 and 170 g/667m2,had good control effect against rice plant hopper,which had long lasting but bad fast-acting effect.After 1 day,3 days,7 days,the control effects ranged from 64% to 71%,75% to 84% and 80% to 95%,respectively,during the years of 2009 to 2010.In production,the reference dose of 24% wettable powder combined with carbaryl and pymetrozine on rice plant hopper was 110～140 g/667m2.