Quinoa drought responses and adaptation

Quinoa thrives under a wide range of soil and climate conditions, from cold and arid areas to wet tropical regions. The adaptability of quinoa to various levels of drought is due to the differentiation of a diversity of ecotypes originating in contrasting agro-environments. Plants display various adaptive strategies to drought stress, from morphological to physiological adaptations that serve a range of responses to water deficit, from avoidance to resistance and tolerance. Plants cope with drought stress by changing and modifying key physiological processes, such as photosynthesis, respiration, water relations and antioxidant and hormone metabolism. Whole-plant responses to drought involve changes in leaf and root growth, in some cases with strong ontogenetic variation. These drought responses at both physiological and morphological levels show intraspecific variation related to ecotypic differentiation. This chapter explores the responses to this abiotic stress and reviews possible mechanisms concurring at both whole plant and tissue level, including recent determinations from architectural, morphological, physiological and molecular perspectives. Quinoa thus represents an invaluable opportunity, both as a potential crop in consideration of present and future climate change challenges, and as an important source of genes with biotechnological applications