Objective:To investigate the inhibition degree of different drought types on seed germination and early seedling growth of Haloxylon ammodendron,with a view to providing scientific support for the efficient cultivation of H.ammodendron seedlings under arid environmental conditions.Methods:Seeds of H.ammodendron were used as materials,PEG was used to simulate soil drought,and NaCl was used to simulate physiological drought.The effects of the two stresses under different isotonic gradients(0,-0.46,-1.38,-2.30,-3.23 Mpa)on the seed germination and early seedling growth of H.ammodendron were studied by determining germination rate,germination potential,germination index,seedling vitality index,seedling growth and seedling root length,root-to-head ratio and other indicators.Results:High concentrations of PEG stress significantly reduced the germination rate,ger-mination potential,germination index,seedling vitality index,seedling length and root length of H.ammodendron,indicating that moderate soil drought could inhibit seed germination and early seedling growth of H.ammodendron.Severe NaCl stress(-3.23 Mpa)significantly reduced germination rate,germination potential and germination index,while seedling vitality index and root-to-head ratio were significantly higher than the control under mild NaCl stress(-0.46 Mpa),indicating that severe physio-logical drought significantly inhibited the germination of H.ammodendron seeds,while mild physio-logical drought promoted the growth of H.ammodendron seedlings at early stage.NaCl stress had higher germination rate,germination potential,germination index,seedling vitality index,seedling length and root-to-head ratio than PEG stress.Conclusion:Soil drought and physiological drought sig-nificantly inhibited seed germination and seedling growth of H.ammodendron,but soil drought inhibi-tion was stronger.H.ammodendron was more suitable for sowing seedlings in arid saline areas where the soil water potential not less than-2.25 Mpa.
NETL
NSTL
万方数据
