沙蒿种子萌发对NaCl及聚乙二醇胁迫的响应

目的]研究在盐分以及干旱胁迫条件下沙蒿种子的萌发能力,为沙蒿的人工培育和栽种提供参考依据。方法]以沙蒿种子为试验材料,使用不同浓度的NaCl溶液(0.2%,0.4%,0.6%,0.8%,1.0%,1.2%,1.4%,1.6%,1.8%)和聚乙二醇(PEG)溶液(5%,10%,15%,20%,25%)模拟盐分以及干旱对种子的胁迫条件,测定种子萌发初期的发芽率、发芽势、发芽指数、活力指数。结果]当NaCl浓度≤0.6%时,上述指标与对照组相比未发生显著变化;但当溶液浓度高于这一范围时,各项指标则随浓度升高而显著降低;说明NaCl溶液浓度为0.6%是种子正常萌发的适宜浓度界限。当PEG浓度≤15%时,沙蒿种子的上述指标与对照组相比未发生显著变化;但当PEG浓度高于15%时,种子各项指标与对照组相比则显著降低;说明PEG浓度为15%是种子正常萌发的适宜浓度界限。结论]沙蒿种子对轻、中度的盐分及干旱胁迫表现出耐受性,在含盐量较低的土壤以及轻、中度的干旱环境中仍可正常萌发。

Response of Seed Germination of Artemisia Desertorum to NaCl and Polyethylene Glycol Stress

Objective]The germination ability of Artemisia desertorum seeds under salt and drought stress was investigated to provide a reference for artificial cultivation and planting of A.desertorum.Methods]Using A.desertorum seeds as experimental materials,different concentrations of NaCl solutions(0.2%,0.4%,0.6%,0.8%,1.0%,1.2%,1.4%,1.6%,and 1.8%)and polyethylene glycol(PEG)solutions(5%,10%,15%,20%,and 25%)were applied to simulate salinity and drought stress conditions on seeds.The germination rate,germination potential,germination index,and vigor index were measured in the early stage of seed germination.Results]When the NaCl concentration was≤0.6%,the above-mentioned indices did not change significantly compared with the control group.However,when the solution concentration was higher than this range,the indices decreased significantly with the increase in concentration.The NaCl solution concentration of 0.6%was the most suitable concentration limit for normal seed germination.When the PEG concentration was≤15%,the above indices of A.desertorum seeds did not change significantly compared with the control group.However,when the PEG concentration was higher than 15%,the seed indices decreased significantly compared with the control group.The PEG concentration of 15%was the most suitable concentration limit for normal germination.Conclusion]A.desertorum seeds showed tolerance to mild and moderate salt and drought stress and could still grow normally in low salt content soil and mild and moderate drought environments.