糖浸种对盐胁迫玉米种子萌发和幼苗生长的影响

Effects of Sugar Immersion on Seed Germination and Seedling Growth of Maize under Salt Stress

以耐盐玉米品种伟科702和盐敏感玉米品种蠡玉16为试验材料,在150 mmol·L^(-1) NaCl胁迫下,采用不同浓度(5、10、15 g·L^(-1))外源糖(葡萄糖、果糖、蔗糖、壳聚糖、海藻糖)浸种处理,分析外源糖对玉米种子发芽指标、幼苗生长、叶绿素含量、SOD活性、POD活性和MDA含量的影响。结果表明,外源糖处理后两个品种的发芽势、发芽率、最终发芽率、发芽指数、生物量、叶绿素含量、SOD活性和POD活性均显著增大,且随着糖浓度的增加呈先升高后下降的趋势,浓度为10 g·L^(-1)时最高;平均发芽时间和MDA含量减小,且随着糖浓度的增加呈先下降后上升的趋势,浓度为10 g·L^(-1)时最低。不同糖处理间比较,果糖处理的各项指标显著优于其他糖处理。因此,外源糖浸种能有效改善盐胁迫下玉米幼苗生长状况,10 g·L^(-1)果糖的改善效果最好。

In this study,the salt-tolerant maize variety Weike 702 and salt-sensitive maize variety Liyu 16 were used as experimental materials to investigate the effects of exogenous sugar on seed germination index,seedling growth,chlorophyll content,SOD activity,POD activity and MDA content of maize were analyzed.The maize seeds were soaked with exogenous sugars(glucose,fructose,sucrose,chitosan and trehalose)at different concentrations(5,10,15 g·L^(-1))under 150 mmol·L^(-1) NaCl stress.The results showed that the germination potential,germination rate,final germination rate,germination index,biomass,chlorophyll content,SOD and POD activities of the two varieties increased significantly after treatment with exogenous sugar,and increased first and then decreased with the increase of sugar concentration,with the highest concentration being 10 g·L^(-1)).The average germination time and MDA content decreased,and decreased first and then increased with the increase of sugar concentration,and reached the lowest when the concentration was 10 g·L^(-1).Compared with other sugar treatments,the indexes of fructose treatment were significantly better than other sugar treatments.Therefore,soaking seeds with exogenous sugar could effectively improve the growth of maize seedlings under salt stress,and 10 g·L^(-1) fructose has the best improvement effect.