不同外源物质对盐碱胁迫下紫苏种子萌发、幼苗生长及生理的影响

Effects of Different Exogenous Substances on Seed Germination and Seedling Growth and Physiology of Perilla frutescens under Saline-alkali Stress

为筛选出促进盐碱胁迫下紫苏种子萌发和幼苗生长的最佳外源物质及其处理浓度,本试验以紫苏种子为材料,研究不同浓度的氯化钙(CaCl_(2))、褪黑素(Melatonin,MT)、赤霉素(Gibberellin,GA)浸种24h对盐碱胁迫下紫苏种子萌发和幼苗生长的影响。结果表明:3种外源物质浸种处理均能够有效缓解紫苏受到的盐碱胁迫,促进种子萌发、幼苗生长,提高抗氧化酶活性。CaCl_(2),MT,GA缓解盐碱胁迫的最佳浓度分别为10mmol·L^(-1),100μmol·L^(-1),50 mg·L^(-1),其中,50mg·L^(-1)GA对促进种子萌发效果最佳,100μmol·L^(-1)MT对促进幼苗胚根伸长和抗氧化酶SOD,CAT,POD活性升高效果最佳,而促进幼苗胚芽伸长和鲜重增加的最佳处理为300mg·L^(-1)GA。利用隶属函数综合评价得出,50mg·L^(-1)GA浸种24h是盐碱胁迫下促进紫苏种子萌发和幼苗生长的最佳处理方法。

In order to screen out the best exogenous substances and the optimal concentration to promote Perilla frutescens seed germination and seedling growth under salt-alkali stress,we studied the effects of different concentrations of calcium chloride(CaCl_(2)),Melatonin(MT)and Gibberellin(GA)on Perilla frutescens seed germination and seedling growth under salt-alkali stress.The results showed that these exogenous substances could effectively alleviate the saline-alkali stress on Perilla frutescens,promote seed germination and seedling growth,and improve the activity of antioxidant enzymes.The optimal concentrations of CaCl_(2),MT and GA were 10mmol·L^(-1),100μmol·L^(-1)and 50mg·L^(-1),respectively.50mg·L^(-1)GA had the best effect on seed germination,100μmol·L-1 MT had the best effect on promoting radicle elongation,superoxide dismutase activity,catalase activity and peroxidase activity,while the best treatment for promoting elongation and fresh weight of seedlings was 300 mg·L^(-1)GA.By comprehensive evaluation of membership function,it was concluded that 50mg·L^(-1)GA soaking for 24hwas the best treatment method to promote the seed germination and seedling growth of Perilla frutescens under saline-alkali stress.