Alleviation of weed stress in wheat (Triticum aestivum) through herbicides andtheir combinations

摘要

A field experiment was conducted during the winter (rabl) seasons of 2012-13 and 2013-14 at Udaipur (Rajasthan), to study the effect of 12 different herbicide combinations to control complex weed flora in wheat (Triti-cum aestivum L.) crop. Pooled data of 2 years experimentation indicated that the application of various herbicide combinations significantly reduced density and biomass of complex weed flora. The yield attributes, viz. plant height, effective tillers, days to heading; days to maturity and 1,000-seed weight were significantly influenced by application of various herbicide combinations. The application of herbicides increased the yield, harvest index and monetary income of wheat crop compared to weedy check, although maximum grain yieldwas recorded under weed free plots. Amongst the herbicides, application of sulfosulfuron + metsulfuron @ 30 + 2 g a.i./ha rsulted in higher number of effective tillers (485.8/m2), the maximum grain yield (5.29 t/ha), harvest index (37.9%), net returns (I.Rs 79,480/ha) and benefit: cost ratio (3.06), which was superior to rest of the treatments, as the same treatment caused significant reduction in weed density (6.65/m2) and weed biomass (6.24 g/m~2). Two-year study indicates that application of a ready-mixed herbicide (sirifosulfuron + metsulfuron) @ 32 g a.i/ha was best for weed-control, higher yield and net returns from wheat in southern plain zone of Rajasthan.