Efficacy of different commercial product oxadiazon and pyrazosulfuron-ethyl on rice and associated weeds in dry season rice cultivation.

摘要

Due to shortage of labor using herbicides is an alternative, effective and economic system of weed management. An experiment was conducted on dry season at Bangladesh Rice Research Institute farm Gazipur (92 degrees 41'E longitude and 20 degrees 34'N latitude), Bangladesh during January-May, 2009 to find out the efficacy of different post emergence herbicide and select cost effective herbicide as weed control option. There were ten different weed control treatments viz. T1=Zealus 10 WP at 125 g ha-1, T2=Amaraj 10 WP at 150 g ha-1, T3=Siniron 10WP at 187 g ha-1, T4=Herbikill 10 WP at 150 g ha-1, T5=Res Q 25 EC at 1.2 L ha-1, T6=Remover 10 WP at 187 g ha-1, T7=Safety 10 WP at 200 g ha-1, T8=Laser 10 WP at 125 g ha-1, T9=Three hand weeding at 15, 30 and 45 DAT and T10=Weedy check. There were 8 different weed species infested the field among which Scirpus maritimsu followed by Echinochloa crusgalli was the most dominated weed in terms of weed density and importance value. Among the treatments T6 gave the lowest weed population, weed dry weight and weed index and highest weed control efficiency. The yield and the yield contributing characters (no. of panicles m-2, no. of grains panicle-1, grain and straw yield) were influenced according to the effectiveness of the treatments. Herbicidal treatment T6 produced similar yield as hand weeding (T9) but weeding cost of T6 was almost one-sixth of T9. Maximum marginal return rate with T6 suggested that this herbicidal treatment could be used as an alternative tool when labor is a limiting factor in dry season rice cultivation.