Comprehensive assessment of salt tolerance in nine spring maize hybrids across the entire growth period
Salt-alkaline soils are one of the major abiotic factors limiting global crop production, and maize is a moderately salt-sensitive crop. With global warming and the widespread use of drip irrigation, maize cultivation faces severe challenges from saline-alkali stress in arid areas. We used nine spring maize hybrids as experimental materials to measure 24 agronomic and physiological traits at the seedling, flowering, and maturity stages in soil with a total salt content of 0.18%–0.61% and a pH of 9.0–9.2 by depth. Salt tolerance and yield evaluations of the tested maize hybrids were performed using principal component analysis, the membership function method, and GGE biplot analysis. The results identified root-to-shoot ratio, leaf Na+/K+ ratio, shoot dry weight and root Na+/K+ ratio as key traits for selecting hybrids with excellent productivity and stability under saline conditions. Additionally, GGE biplot analysis indicated Dika159 (H7) demonstrated superior productivity and stability in all test environments. These results facilitate the development of salt-tolerant maize germplasm and the breeding of stable and adaptable hybrids for saline-alkaline soils.