Upland rice: phenotypic diversity for drought tolerance

ABSTRACT: Upland rice is cultivated mostly in Latin America and Africa by small farmers areas with risk of dry spells. This study evaluated morphophysiological mechanisms upland associated to drought adaptation. A set 25 genotypes were grown a plant phenotyping platform during 2015 2017 under regular irrigation water restriction. We traits shoots (vegetative structures growth, gas exchange, use efficiency, carboxylation status) roots (length, surface area, volume diameter), as well agronomic (grain yield its components). There was reduction grain up 54 % 58 2017, respectively, deficit. Five the best performances both treatments applied recommended rice-breeding program: Bico Ganga, BRS Esmeralda, BRSMG Curinga, Guarani, Rabo de Burro. In this study, tolerance concerned high capacity save leaves, low leaf potential, ability reduce vegetative structures, photosynthetic capacity, improved absorb from drying soil, either osmotic adjustment or additional investment into root system. Therefore, we concluded that different secondary contributed should be along improve efficiency breeding selection.