Effect of different legumes on nutrient acquisition and soil biological indicators of basmati rice

In order to assess the long-term impact of legume integration on basmati rice, five production systems, viz., Fallow, Basmati rice -wheat- Dhaincha (Sesbania aculeata), Basmati rice-kabuli chickpea- mung bean, Basmati rice- chickpea- mung bean, Basmati rice-berseem-mung bean were evaluated in four times replicated Randomized block design during 2016-23. Results revealed that legume integration significantly enhanced yield-attributing traits such as tillers m-2, panicle density, and grains panicle-1. Among the tested production systems, cultivation of basmati rice-berseem-mung bean system consistently outperformed others, recording 4.5% and ~6.3% higher tillers and grains panicle-1 than basmati rice-chickpea-mung bean, respectively. Grain and straw nutrient concentration (N, P, and K) were also maximized under basmati rice-berseem-mung bean and basmati rice- wheat-dhaincha system. Soil biological indicators showed similar trends, with microbial biomass carbon (MBC) and microbial biomass nitrogen (MBN) being highest under basmati rice-berseem-mung bean, which recorded 205.75 μg g-1 MBC and 19.48 μg g-1 MBN in the 0-15 cm soil layer. Microbial activity decreased with depth but remained consistently higher under legume systems compared to fallow. The findings infrred that integrating berseem or dhaincha in basmati rice-based systems improves yield attributing parameters, grain and straw nutrient content, and soil biological resilience. Thus, berseem inclusion is recommended as a sustainable intensification strategy to ensure long-term basmati rice sustainability in the Indo-Gangetic Plains