盐-旱胁迫下苦豆子种子萌发和幼苗生长的响应特征OA

To clarify the tolerance range of Sophora alopecuroides during early growth stages under salt and drought stresses,we investigated the response characteristics of seed germination and seedling growth using seeds and seedlings from the Kashgar Prefecture,Xinjiang,by setting NaCl gradients and NaCl×PEG composite gradients.The results showed that the response of S.alopecuroides to salt-drought stress exhibited significant stage-specific differentiation.Seed germination was highly sensitive to salinity,with 100 mmol·L-1 NaCl identi-fied as the critical concentration for germination inhibition.Under combined stress,the combination of high salin-ity and high PEG concentration severely suppressed germination.Seedlings demonstrated a broader tolerance range,maintaining steady growth at 50 mmol·L-1 NaCl.However,the tolerance ceiling was observed at 100 mmol·L-1 NaCl+40%PEG,beyond which root growth and biomass decreased significantly.Comprehensive anal-ysis indicated that salinity is the primary factor limiting the early growth of S.alopecuroides,while severe drought(40%PEG)synergistically amplifies the deleterious effects of ion toxicity.These findings define the physiological tolerance thresholds during the early life history of S.alopecuroides,providing quantitative evi-dence for seed-based restoration and ecological recovery in arid regions.