To screen salt-tolerant Medicago sativa L. germplasm， 43 alfalfa hybrid F₂ materials were treated with four NaCl concentrations （0%， 0.3%， 0.6%， and 1.2%）. Agronomic traits， including germination potential， germination rate， fresh weight， shoot length， and root length， were measured， and key physiological indicators such as proline and malondialdehyde were analysed. Principal component analysis， membership function method， and cluster analysis were used to comprehensively evaluate salt tolerance at the germination stage. The results indicated that 0.6% NaCl was suitable for screening salt tolerance at this stage. Germination rate， root length， shoot length， and relative proline content （R-Pro） were identified as core indicators for evaluation. Seven highly salt-tolerant materials—GW141， GD131， GZ21， GW71， GD111， GD171， and GD301—were selected， which exhibited both agronomic advantages （“high germination rate and strong root development”） and physiological resistance （“strong osmotic adjustment and weak membrane lipid peroxidation”） under salt stress， providing valuable candidates for salt-tolerant breeding and saline-alkali soil improvement.

Alfalfa  /  Salt stress  /  Germination stage  /  Salt tolerance  /  Physiological indicators  /  Comprehensive evaluation  /  Germplasm screening