Sesbania brown manuring improves soil health, productivity, and profitability of post-rice bread wheat and chickpea

Abstract

Summary Continuous rotation of rice with wheat in rice–wheat system has resulted in stagnant yields and reduced profit margins while deteriorating the soil health. Legume incorporation in existing rice–wheat rotations might be a viable option to improve soil health and productivity. We investigated the influence of puddled transplanted flooded rice and direct-seeded rice on weed dynamics, soil health, productivity, and profitability of post-rice wheat and chickpea grown under zero tillage and conventional tillage. The previous direct-seeded rice crop was either sown alone or intercropped with sesbania as brown manure. The experiment comprised different rice–wheat and rice–chickpea systems which had been in place for two years: with and without rice residue retention. The initial soil analysis indicated that the plots with sesbania brown manuring in direct-seeded rice had the lowest soil bulk density (17.2%) and highest soil porosity (19.3%). Zero tillage in wheat or chickpea in the plots previously cultivated with co-culture of sesbania and direct-seeded rice increased total soil organic carbon by 13–22% in both years. The plots with sesbania brown manuring in direct-seeded rice followed by zero till or conventional till wheat and the plots with direct-seeded rice followed by zero till wheat with rice residue retention recorded the greater concentrations of total nitrogen, available phosphorus, and exchangeable potassium. Zero tillage in wheat and chickpea in post-rice sesbania brown manuring plots produced 41% and 43% more grain yield than those in the puddled transplanted flooded rice with conventional tillage and had the highest profitability. Overall, the rice–chickpea systems had better soil health and profitability than rice–wheat cropping systems. In conclusion, direct-seeded rice intercropped with sesbania followed by wheat and chickpea under zero tillage suppressed weed flora and improved soil physical properties, nutrient availability, productivity, and profitability.