Abstract:

【Objective】To explore the effects of salt and drought stress on Allium mongolicum Regel seed germination，and to provide references for the study of artificial cultivation and stress tolerance of Allium mongolicum Regel.【Methods】Taking Allium mongolicum Regel seeds as test material，different concentrations of NaCl and Na₂SO₄ neutral salt mix solution and PEG-6000 solution were used to simulate salt and drought stress. The germination rate，germination potential，germination index and vitality index were tested. The functional equation created by the relative germination rate and each treatment concentration was used to determine the seed tolerance.【Results】Allium mongolicum Regel seeds germination indicators gradually decreased as salt and drought stress increased，and the initial germination time delayed. When the salt concentration was 75 mmol/L and 150 mmol/L，seeds germination time delayed to the day 3 and day 5，respectively，and the germination rate fell to 23.33% and 12.66%，respectively. When the concentration of PEG-6000 was 15% and 20%，the seeds germination time delayed to day 3 and day 4，respectively，and germination rate fell to 38.66% and 25.33%，respectively. The salt tolerance and drought resistance semi-lethal osmotic potentials were -0.20 MPa and -3.80 MPa，and the salt tolerance and drought resistance limit osmotic potentials were -0.60 MPa and -7.38 MPa，respectively.【Conclusion】The seeds germination of Allium mongolicum Regel was not significantly suppressed under mild drought stress，with drought tolerance limit osmotic potential of -7.38 MPa. Low-permeability salt solution significantly inhibited Allium mongolicum Regel seed germination，with salt tolerance limit osmotic potential of -0.60 MPa.

Key words: Allium mongolicum Regel seeds, Salt stress, Drought stress, Germination