Résumé
Legumes rank third in world crop production, and abiotic stress is the major constraint to crop productivity. Biotechnological applications including all “omics” have been the direct and potential approaches for improving abiotic stress tolerance in grain legumes and requires knowledge of stress response at molecular level, which includes gene expression to protein or metabolite and its phenotypic effects. Genome‐wide expression profiling studies have been carried out in the legumes to identify the candidate genes and regulatory networks among abiotic stress responses. Among the grain legumes, although soybean has been more intensively studied, more recently, sensitive and tolerant varieties of chickpea and peanut have been characterized under abiotic stress conditions. Nevertheless, proteomic studies in response to abiotic stress in legumes are still very limited with only Medicago truncatula and soybean protein reference maps available. Some of the major QTL controlling abiotic stress tolerance in legumes have been mapped for a major QTL for salt tolerance in soybean and drought tolerance‐related traits in peanut. Although, Agrobacterium‐mediated gene transfer has been reported in all the major legume crops, so far only one legume, that is, soybean, has been commercialized. Transgenic technologies for improved abiotic stress tolerance involving regulatory genes have proved more efficient than using single or multiple functional genes involved in stress tolerance. Hence, the current advances in “omics” technologies and availability of the genome sequences of model legumes and soybean offer great potential to improve the stress tolerance of the legume crops. This chapter attempts to provide a detailed discussion about the different “omics” approaches and their applications for abiotic stress research on major legumes.