Legumes and Nodule Associated Bacteria Interaction as Key Factor for Abiotic Stresses Impact Mitigation

Abstract

Due to climate change, different soil stresses are increasing continuously and they threat the world food security as they limit crop productivity. Therefore, this chapter aims at integrate information about the interaction between legumes and endophytes which will help to: deep understanding of the endophytes-legume relationship, draw attention to the possibilities to exploit this relationship in soil stress mitigation and unraveling what is need to be addressed in the future. The study reviewed the most recent previous scientific works in the field. For legumes tissue colonization, endophytes almost use the same routs which results in their presence in the same niches. Co-inoculation of these bacteria enhances plant growth directly and indirectly. Some endophytes characterized by stress tolerance which interact with legumes and mitigate the adverse effect of soil stresses like salinity, acidity/alkalinity, drought and heavy metal contamination. To reduce stress and enhance plant growth, legume-associated bacteria produce ACC deaminase and other compounds. The interaction process involves induction and expression of many legume-associated bacteria chromosomal and plasmid genes which indicates that this process is a genetic based. So isolation of stress tolerant legume-associated microbes and identification of the gene related to stress tolerance will aid in production of genetic engineered endophytes adaptive to different stresses. It is concluded that all soil stresses can be addressed by application of stress tolerant endophytes to the soil affected with environmental stresses which is sustainable and low cost approach. To maximize the benefit, searching for indigenous stress tolerant endophytes is recommended.