Effect of Organic Mulching and Early Post Emergence Herbicides on Weed Dynamics and Growth of Unpuddled Transplanted Rice

Abstract

Field studies were carried out in 2017 and 2018 at Agricultural Research Farm, Banaras Hindu University Varanasi, Uttar Pradesh, India, to evaluate the effect of natural mulching and herbicides on weed dynamics and growth of rice. The experiment was laid out in a split plot design with three mulching treatments viz. no mulching, cover crop of Sesbania followed by green mulch and rice residue mulch (5 t/ ha) in main plots and five weed management treatments, viz. weedy, two hand weeding, post-emergence application of bispyribac Na 25 g/ ha, penoxsulam 30 g/ ha and tank mix bispyribac Na 25 g/ ha + pyrazosulfuron 20 g/ ha at 18 DAT in sub plots. Combination of main plot treatments and sub plot treatment allocated randomly and all the treatment combination were replicated thrice. The study revealed that mulching with Sesbania provided effective control of weeds, recorded significantly higher growth attributes and biological yield as compared to no mulching in both the years. Among weed management treatments two hand weeding resulted significant reduction in density and dry matter of weeds and increased yield which was at par with post-emergence application of penoxsulam 30 g/ha in both the years Treatment combination of surface mulching of Sesbania with two hand weeding recorded significantly higher number of tillers, as compared to other treatment combinations, it was at par with combination of surface mulching with Sesbania and post-emergence application of penoxsulam  30 g/ha and rice straw mulching and post-emergence application of penoxsulam  30 g/ha.