8种豆梨无性系对盐胁迫的生理响应

Physiological Responses of Eight Pyrus Calleryana Decne.Clones to Salt Stress

以豆梨实生苗为试材,采用盆栽试验,浇灌浓度为0(CK)、4、8、12、16‰的NaCl溶液,观测其生理指标(SOD、POD、CAT、APX、H2O2和MDA)变化;再以8个豆梨品系(种)为试材,浇灌浓度为0(CK)、8‰的NaCl溶液,测定其生理指标,评价各品系(种)的耐盐性。结果表明:随着NaCl胁迫增强,豆梨MDA和H2O2有显著升高,随着保护酶系统的启动,代谢中产生的H2O2的含量又逐渐减少,避免了膜脂过氧化,有利于豆梨在较低浓度盐胁迫下正常生长;随着盐处理浓度增加,保护酶SOD、POD、CAT均呈先升高后降低的变化趋势,APX呈先减低后升高变化趋势;用8‰NaCl溶液分别处理各系号,发现与对照相比,各系号各指标变化规律不明显,各系号间有显著差异;采用模糊数学隶属函数法对8个豆梨品系(种)的耐盐能力进行综合排序,发现耐盐能力较强的有m11、m24和sd,j2、j8耐盐能力中等,m21、m10和m12耐盐能力较弱。

Pot experiment was conducted with P.calleryana seedlings as test materials,and NaCl solution with concentration of O(CK),4,8,12,16%o was irrigated to observe the changes of physiological indexes;Then,eight P.calleryana of lines(species)were used as test materials,and NaCl solution with concentration of O(CK)and 8%o was irrigated to measure their physiological indexes and evaluate the salt tolerance of each line(species).The results showed that with the increase of NaCl stress,MDA and H2O2 of P.calleryana increased significantly.With the start of the protective enzyme system,the content of H2O2 produced in metabolism decreased gradually,avoiding membrane lipid peroxidation,which was conducive to the normal growth of P.calleryana under low concentration salt stress;With the increase of salt concentration,the protective enzymes SOD,POD,CAT all increased first and then decreased,and APX decreased first and then increased;It was found that the change rule of each index of each line number was not obvious compared with that of the control group,and there was a significant difference between each line number when each line number was treated with 8%o NaCl solution;The subordination function method of fuzzy mathematics was used to comprehensively rank the salt tolerance of eight P.calleryana lines(species).It was found that the stronger salt tolerance were mll,m24 and sd,the middle salt tolerance was j2 and j8,and the weaker salt tolerance was m21,m10 and m12.