Seed Coating in Direct Seeded Rice: An Innovative and Sustainable Approach to Enhance Grain Yield and Weed Management under Submerged Conditions

Dry direct-seeded rice is an alternative cropping technique that should require less water and labor than the classical method of transplanted-flooded rice. Weed competition is the major biological constraint in this resource-conserving production technique reducing the crop yield by 30–80%. This study evaluated the effects of different seed coating treatments on the performance of dry direct seeded rice under field conditions. The seed coating treatments used were preliminarily optimized under lab conditions. The rice seeds were coated with sodium lauryl sulphate (20:1), calcium peroxide (CaO2 ) (20:6), alginate (20:6), and plant growth promoting bacteria Bacillus sp. KS-54 (20:6 g:mL) on a dry weight basis. Among treatments, seed coating with CaO2 resulted in higher field emergence (85%) and suppressed the fresh and dry biomass of weeds at 15 and 35 days after sowing which subsequently improved the seedling growth of direct seeded rice followed by other treatments and the control. Rice seeds coated with CaO2 and Bacillus sp. KS-54 were effective at enhancing morphological, yield and yield related attributes as compared to other treatments and the control under field conditions. The better morphological attributes and yield of rice plants raised from seeds coated with CaO2 and Bacillus sp. KS-54 were associated with higher concentrations of reducing sugars and enhanced antioxidant enzymes activities.