Weed Management in Legume Crops-Current Advances, Challenges and Future Perspectives: A Review

Abstract

Weeds are a serious limitation to legume crop productivity worldwide. This review brings together Indian and international literature on weed flora, critical period of weed competition (CPWC), cultural, mechanical, chemical, biological and integrated weed management (IWM) strategies in legume crops, with special emphasis on the impact on rhizobial nodulation and biological nitrogen fixation (BNF), herbicide resistance, bioherbicides, climate change interactions, emerging herbicide-tolerant cultivars and precision agriculture technologies. Yield losses have been reported to be as high as 25% in short-duration Indian legume crops, 85% in Mediterranean chickpeas and as high as 91% in North American row crops under season-long weed competition. The review incorporates substantial evidence from Indian Journal of Agronomy, Indian Journal of Weed Science and Journal of Food Legumes, together with international literature from Australia, Canada, the USA, Brazil, the Mediterranean region and Africa. Herbicide options are evaluated for effectiveness, timing, crop safety and nodulation effects and dedicated sections on herbicide resistance and weed-flora change, bioherbicides, climate change effects on weed behaviour and herbicide effectiveness, herbicide-tolerant cultivar development and precision technologies, with clear knowledge gaps and future research priorities. Integrated weed management (IWM) that integrates cultural, chemical, biological and precision technologies stands out as the most sustainable approach to protect legume yield and nitrogen fixation under new climatic conditions.