Herbicidal weed management in groundnut (Arachis hypogaea) and its residual effect on succeeding wheat (Triticum aestivum) crop

A field experiment was carried out at Mandore, Jodhpur, Rajasthan, during the rainy (kharif) and winter (rabi) seasons of 201718 and 201819, to study the herbicidal weed management in groundnut (Arachis hypogea L.) and its residual effect on succeeding wheat (Triticum aestivum L.) crop in the western Rajasthan. The experiment was laid out in a randomized block design with 14 treatments and replicated thrice. Weed-free (2 hand-weedings) treatment recorded significantly higher pod yield over rest of the treatments. Among the herbicidal treatments, pendimethalin 30 EC + imazethapyr 2 EC @ 1,000 g/ha pre-emergence (PE) treatment (T5) led to the lowest weed density, weed biomass, and achieved the maximum weed-control efficiency. This T5 treatment was statistically significant over the T4 (pendimethalin 30 EC + imazethapyr 2 EC @ 750 g/ha PE), T12 [sodium aciflourfen 16.5% + clodinafop propargyl 8% @ 200 g/ha post-emergence (PoE)] and T11 (sodium aciflourfen 16.5% + clodinafop propargyl 8% @ 180g/ha PoE) in relation to pod yield. Our results also revealed that application of pendimethalin 30 EC + imazethapyr 2 EC @ 1000 g/ha PE enhanced the cropping system gross returns, net returns and benefit:cost (B:C) ratio over the control. But showed equal economic feasibility with pendimethalin 30 EC + imazethapyr 2 EC @ 750 g/ha PE, sodium aciflourfen 16.5% + clodinafop propargyl 8% @ 200 g/ha PoE and sodium aciflourfen 16.5% + clodinafop propargyl 8% @ 180 g/ha PoE. Imazethapyr + imazamox (pre-mix) @ 70 g/ha PoE also effectively controlled the weed in groundnut and found statically at par with above treatments. Residual effect of different concentrations of herbicide was not observed in succeeding wheat in groundnutwheat cropping system.