Genetic engineering of legumes for abiotic stress tolerance

The Fabaceae or Leguminoseae is a family of flowering plants called legumes which are culturally and economically important plants due to their extraordinary diversity, abundance, medicinal uses, and varied variety of edible vegetables. These plants are also important because legumes help in nitrogen fixation and thus reduce the cost of fertilizers for farmers. However, it was observed in past decades that climate change and anthropogenic activities have created stress-like conditions for various plants. Different kinds of environmental stresses including high/low temperature, salinity, drought, nutrient deficiencies are known to cause considerable losses in crop yield. Because plants are sessile in nature, they have developed a series of complex phenomena to combat a variety of abiotic stresses. Plants deal with abiotic stresses by activation/deactivation of a number of genes involved in different pathways. The gene products which are produced as a result of stress-induced gene expression can provide direct protection against these stresses and others that are responsible for gene expression regulation and signal transduction. Understanding varied stress responses in plants can help in producing better cultivar and improvisation of species. Various techniques such as marker-assisted breeding, tissue culture, somaclonal variations and in vitro mutagenesis, double haploids, wide hybridization, and genetic transformation have been used to reduce some of these constraints. Transgenic techniques are helpful in producing improved germplasm exhibiting tolerance to abiotic stress as well as resistance to various diseases resulting in better crop quality with increased productivity. This chapter focuses on the use of transgenic techniques for abiotic stress tolerance in legumes.