Broad leaf weed management in wheat by pre-emergence and pre-mix post-emergence combinations of herbicides under different irrigation schedule

Abstract

A 2-years study was conducted to assess the impact of irrigation schedule and weed management practices on broad leaf weed (BLW) flora and wheat dry matter production. Experiments were conducted during Rabi season of 2017-18 to 2018-19 at CSAUAT, Kanpur under split-plot design with four replication having four irrigation regimes were assigned to main plots and eight weed management practices were allocated to sub plots. Irrigations at crown root initiation (CRI) and active tillering stage (I1) significantly reduce the density and weight of BLW with highest WCE and crop resistance index (CRI) over other irrigation regimes. However, irrigation at CRI+ jointing+ booting+ flowering+ milking stage (I4) recorded highest weed effectiveness (WE) and dry matter yield (CDMY) followed by irrigation at CRI + active tillering + booting + flowering stage (I3). All the weed management treatments significantly reduced the density and weight of BLW resulted maximum crop dry matter yield over weedy check. Among herbicidal treatments, lowest density, fresh and dry weight of BLW, WE and the highest WCE, CRI, WPI and CDMY was recorded with the application of broadway (carfentrazone ethyl 20% + sulfosulfuron 25%WG) 100 g ha-1 at 35 DAS and it was statistically at par with clodinafop- propagyl 15% + metsulfuron 1% 400 g ha-1 at 35 DAS.