Influence of Different Nitrogen Levels and Weed Management Practices on Leaf Area Index of Dry Direct Seeded Rice (Oryza sativa L.) Under Temperate Conditions

Abstract

Dry direct-seeded rice (DDSR) is an increasingly important cultivation method in regions facing water scarcity and labour constraints. Optimizing nitrogen application is instrumental in determining the environmental sustainability and economic feasibility of a farming system, making its management a top priority. In addition, the weed problems in dry direct-seeded rice account for the yield reduction and diminish the market value by reducing the product quality and raising the postharvest cost. Considering this, the present investigation was accomplished at MRCFC, SKUAST-K, Khudwani during Kharif 2022 and 2023. The experiment encircled the employment of four nitrogen levels: 0 kg N ha-1(N0), 60 kg N ha-1 (N1), 120 kg N ha-1 (N2), and 150 kg N ha-1 (N3). Additionally, seven weed management practices were employed encircling Pendimethalin at 1 kg ha-1 (3-4 DAS) + 2,4-D at 0.75 kg ha-1 (20 DAS), penoxsulam at 22.5 g ha-1 (12-15 DAS), Pyrazosulfuron combined with Pretilachlor at 30 g + 0.75 g ha-1 (3-4 DAS), Bensulfuron Methyl combined with Pretilachlor at 30 g + 0.75 g ha-1 (3-4 DAS), and Triafamone combined with Ethoxysulfuron at 40 g + 20 g ha-1 (12-15 DAS). The treatments also included a weedy check and a weed-free control. The experiment was designed in line with the factorial randomized complete block design (RCBD) possessing three replications. The acquired results elucidated a considerable increase in growth attributes such as leaf area index in response to various nitrogen levels as well as weed management approaches. Employment of nitrogen @ 150 kg ha-1 and Triafamone + Ethoxysulfuron (40+20 g ha-1) application, in addition to weed-free treatment, recorded the highest values for Leaf area index during 2022 and 2023.