The plants and microorganisms in their natural environment are exposed to different abiotic stresses being drought one of the most worrying. The peanut-rhizobium interaction constitutes one of the most interesting alternatives for the development of a sustainable agriculture given the high agronomic value of the legume in Argentina, especially in the province of Córdoba, and the benefits of the biological nitrogen fixation process. However, such interaction may be affected by the occurrence of episodes of drought. Under these conditions, plants accumulate reactive oxygen species generating oxidative stress and activate their antioxidant system. Plants also accumulate compatible solutes, within which proline is of utmost importance since in recent years it has been proposed to be involved in the cellular redox balance. Thus, the aim of our research is currently focused on analyze the proline metabolism role in the redox-mediated stress response in peanut cultivars with differential tolerance to drought. The use of peanut cultivars with differential levels of tolerance to drought stress, the correlation with endogenous proline levels, the use of aminoacid analogues (inhibitors of proline catabolism enzymes) and the application of exogenous proline, will allow to demonstrate the role of the aminoacid in the defense strategy of plants in a crop of regional importance. These studies are expected to optimize crop production, favoring the maintenance of soil resources, and contribute to increase yield in current employed areas or to extend the production to new agricultural areas.