Inhibitory effects of certain herbicides on panicles formation and grains production of wild oats in wheat fields.

摘要

The efficacy of clodinafop-propargyl [clodinafop], fenoxaprop-P-ethyl [fenoxaprop-P] and tralkoxydim against wild oats (Avena fatua and A. sterilis) in wheat (cv. Sakha-69) fields was evaluated in Giza, Egypt, during 2000-01 and 2001-02. The herbicides were applied at recommended rates (50, 90 and 238 g a.i./ha, respectively) at 40 and 90 days after sowing (DAS), or at 2-fold the recommended rates (double rates) at 90 DAS. Clodinafop-propargyl, fenoxaprop-P-ethyl and tralkoxydim significantly reduced the number of panicles (by 96.7-99.9, 97.9-99.9 and 60-99%, respectively), number of grains/m2 (98.3-99.9, 97.9-99.9 and 59.7-99.1%) and dry weight (76.9-98.7, 59.7-98.5 and 46.2-95.5%) of wild oats. The most effective treatments were clodinafop-propargyl applied at the recommended rate at 40 DAS and fenoxaprop-P-ethyl applied at the higher rate. The herbicides were more effective in the enhancement of wheat grain yield and yield components (number of spikes, grain weight per spike and 1000-grain weight) when applied at recommended rates. The highest yields were obtained with recommended rates of clodinafop-propargyl, fenoxaprop-P-ethyl and tralkoxydim in 2000-01 (6.49, 6.46 and 6.18 t/ha) and 2001-02 (5.51, 5.39 and 5.14 t/ha)..