温度与盐胁迫对盐生草种子发芽特性和幼苗生长的影响

Effects of Temperature and Salinity on Seed Germination and Young Seedling Growth of Halogeton glomeratus

目的:探讨温度与盐胁迫及其交互作用对盐生草种子发芽及幼苗生长的影响。方法:设置20/5℃、25/10℃、30/15℃和35/20℃四组温度条件与0、50、100、200、300、400、600 mmol·L^(-1)七组NaCl胁迫处理,研究不同条件下盐生草种子发芽与早期幼苗生长的差异及特征。结果:盐分、温度均显著地影响了盐生草种子的发芽率、发芽速率、发芽势,以及幼苗的芽长与根长,其中,盐分的影响较温度更大。盐生草种子发芽率在30/15℃和35/20℃下最大,显著高于20/5℃或25/10℃(P<0.05);在30/15℃下,随着盐分增加,盐生草幼苗芽长和根长均表现为先增大后减小的趋势,表明该温度下,50 mmol·L^(-1)盐分可以促进盐生草幼苗的生长;其它温度条件下,随着盐分增加,盐生草幼苗根长均随着盐分增加而减小。结论:30/15℃为盐生草种子发芽时期的适宜温度,且该温度促进了盐生草种子发芽的耐盐性。

Objective:In order to explore the effects of temperature,salinity stress and their interaction on seed germination and seedling growth of Halogeton glomeratus.Methods:20/5℃,25/10℃,30/15℃and 35/20℃and 0,50,100,200,300,400 and 600 mmol·L^(-1) NaCl concentrations were set to study the differences and characteristics of seed germination and early seedling growth of H.glomeratus under different treatments.Results:Two-way ANOVA showed that salt,temperature and their interaction signifi‐cantly affected the germination percent,germination rate,germination potential,seedling bud length and root system of H.glomeratus seeds,among which salt had a greater impact on germination percent,germination rate,germination potential,seedling bud length and root system,while temperature had a smaller impact on these indicators.The germination percent of H.glomeratus seeds was the highest at 30/15℃and 35/20℃,which was significantly higher than20/5℃and 25/10℃(P<0.05);At 30/15℃,with the increase of salinity,the bud length and root length of H.glomeratus seedlings in‐creased first and then decreased,indicating that 50 mmol·L^(-1) salinity promoted the growth of H.glomera-tus seedlings more significantly at this temperature.However,at other temperatures,the root length of H.glomeratus seedlings decreased with the increase of salinity.Conclusion:30/15℃was the appropriate temperature for the germination period of H.glomeratus seeds,and the appropriate temperature promoted the salinity tolerance of H.glomeratus seeds.