Effect of pre- and post-emergence herbicides on weed management, yield and profitability of Indian mustard in northern Haryana

Indian mustard (Brassica juncea (L.) Czern.) is a major oilseed crop in India with diverse industrial applications. However, weed infestation severely constrains crop growth, yield and quality. To evaluate the response of different pre- and post-emergence herbicides, a field experiment was conducted over two consecutive years at Research Farm of the Maharishi Markandeshwar (Deemed to be University) Mullana, Ambala, Haryana. Eleven weed management treatments were laid out in a randomized block design with three replications. The treatments included pendimethalin pre-emergence (PRE) at 750 g ha-1, pendimethalin PRE at 1000 g ha-1 + one hand weeding at 30 DAS, quizalafop-ethyl PRE at 60 g ha-1, quizalafop-ethyl PRE at 60 g ha-1 + one hand-weeding at 30 DAS, clodianafop post emergence (PoE) at 60 g ha-1, oxyfluorfen PRE at 150 g ha-1, oxyfluorfen PRE at 150 g ha-1 + one hand-weeding at 30 DAS, oxadiargyl PRE at 90 g ha-1, oxadiargyl PRE at 90 g ha-1 + one hand-weeding at 30 DAS compared with weed free and weedy check treatments. Among all treatments, the weed-free plot showed the best overall performance. Among herbicidal options, PRE application of oxadiargyl at 90 g ha-1 combined with one hand weeding provided excellent weed control, with the highest weed control efficiency recorded at 30 DAS (75.3 and 67.2 %) and 60 DAS (94.9 and 92.8 %). This treatment also resulted in significantly higher seed yield (1776 and 1393 kg ha-1), stover yield (4977 and 4157 kg ha-1) and harvest index (26.30 and 25.10). The highest gross and net returns, along with B:C ratio (1.92 and 1.62), were recorded with PRE application of oxadiargyl alone, closely followed by its integration with one hand weeding.