Climate Change Impacts on Legume Physiology and Ecosystem Dynamics: A Multifaceted Perspective

As valuable sources of plant-based protein, leguminous vegetables (grain legumes) are essential for global food security and contribute to body growth and development in humans as well as animals. Climate change is a major challenge for agriculture development that creates major problems for the growth and development of plants. However, legume productivity is threatened by climate change factors, including rising temperatures, shifting precipitation patterns, increased atmospheric carbon dioxide levels, intensified extreme events, and altered pest/pathogen activity. This review synthesizes approximately 136 studies to assess the climate effects on major legume crops. Under all the global emissions trajectories, the mean temperatures are projected to rise beyond the optimal legume growing thresholds by 2050, carrying yield reductions between 10 and 49% for beans, soybeans, cowpeas, and lentils without adaptation measures. The elevated carbon dioxide may transiently enhance the yields up to 18%, but the benefits dramatically decline above 550 ppm and cannot offset the other climate impacts. Altered rainfall along with recurrent drought and heat waves are also expected to decrease the legume crop yields, seed quality, and soil nitrogen levels worldwide. Furthermore, the proliferation of legume pests and fungal diseases poses significant risks, amplified by climate shifts in 84% of the reviewed studies. These multifaceted impacts threaten the productivity gains in leguminous vegetables essential to sustainably meeting the global protein demand. Realizing resilience will require the accelerated development of heat/drought-tolerant legume varieties, enhanced climate-informed agronomic practices, strong policy interventions, and social safety nets explicitly supporting legume producers, in addition to the policies/steps that governments are taking to address the challenges of the climate crisis. This review highlights the essential adaptations and mechanisms required for legume crops to thrive and fulfill their significant roles in global nutrition. It explores how these crops can be improved to better withstand the environmental stresses, enhance their nutritional profiles, and increase their yields. Additionally, the review discusses the importance of legumes in sustainable agriculture and food security, emphasizing their potential to address the future challenges in feeding the growing global population. By focusing on these critical aspects, the review aims to underscore the importance of legumes in ensuring a healthy and sustainable food supply.