Innovative approaches of brown manuring induction as a strategic path to harmonize ecosystems and leveraging agricultural sustainability

Global agriculture faces mounting pressure to sustain crop productivity while reducing dependence on synthetic inputs and minimising environmental harm. Brown manuring (BM) is a zero-tillage variant of green manuring in which a cover crop, grown alongside the main crop, is chemically desiccated at the flowering stage using a selective herbicide, typically 2,4-dichlorophenoxyacetic acid (2,4-D). Unlike conventional green manuring, BM does not require mechanical incorporation of plant material into the soil, thereby preserving soil structure and reducing labour costs. Upon desiccation, the standing biomass decomposes in situ, releasing N (up to 35–40 kg N ha −1 from leguminous species such as Sesbania spp. and Crotalaria juncea ), P and K, while improving soil organic carbon content, microbial biomass, and water-holding capacity. BM has been shown to suppress weed populations by 40–94% through light interception, allelopathic effects, and surface mulch formation, thereby reducing dependence on chemical herbicides. When integrated with recommended nutrient management, BM has delivered crop yield improvements of 13–38% in rice, maize, and sugarcane systems. Additional benefits include reductions in greenhouse gas emissions particularly methane by 28–61% when leguminous cover crops are used, alongside improved energy-use efficiency under no-tillage conditions. Despite these well-documented advantages, most existing studies are short-term and site-specific, which limits the broader applicability of findings. Long-term, multi-location field trials are therefore needed to comprehensively assess BM’s sustained effects on soil health, disease suppression, and farm-level economic returns across diverse agro-ecosystems. This review consolidates current evidence and highlights priority research areas to support wider adoption of BM within sustainable crop production systems.