Physiological classification of drought tolerance in soybean genotypes

BUSTAMANTE OM; POSADA GA; SUAREZ P; ESPINOSA HERLEIN MA; MONTEOLIVA MI; GUZZO MC

Rosario

Congreso; Congreso de la Sociedad de Fisiologia Vegetal 2023; 2023

SAFV

Drought is one of the most limiting environmentalfactors in agriculture. Water deficit reduces plant growth and altersdevelopment, reducing crop yields. Soybean is one of the most important cropsworldwide in grain productivity and sown area. To improve productivity underdrought, it is relevant to identify and characterize tolerant soybeangenotypes. Drought tolerance could manifest in physiological responses, such ashigher relative water content (RWC), fresh and dry biomass accumulation, orbiochemical responses such as higher chlorophylls, proline, or FRAP, or lowerMDA (oxidative damage). This project aimed toclassify soybean genotypes under controlled drought. We evaluated soybean linesfrom EEA Marcos Juárez (INTA), grown in greenhouse, with supplemental light andtemperature control. All plants were well watered until the second trifoliateleaf emerged. Then, half of the plants were subjected to water shortage. Theywere daily monitored until soil moisture reached 30% of soil maximum capacityand kept at that level for one more week, when they were measured andharvested. We found variability in stress responses, with genotypes that keephigher RWC than 70%. Greenness increased under drought for all materials. Wealso found variability in proline, FRAP and chlorophylls.  Funds: INTA-PE-2019-I127,INTA-PD-2023-I084, INTA-PE-2023-I111, PICT 2018-01326.