混合盐碱胁迫对不同种源沙枣幼苗的影响

Effects of Mixed Saline-alkali Stress on Elaeagnus angustifolia Seedlings from Different Provenances

以宁夏银川、甘肃张掖的2年生沙枣幼苗为试材,选定4种盐NaCl、Na_(2)SO_(4)、NaHCO_(3)、Na_(2)CO_(3)组成混合盐碱(体积比为1∶1∶1∶1,pH=9.65),模拟5个盐分梯度(土壤中盐的质量分数分别为:0、0.3%、0.6%、0.9%、1.2%)的土壤环境,观测不同盐分梯度时沙枣的生长、理化性质,对丙二醛质量摩尔浓度、可溶性糖质量分数、可溶性蛋白质量分数、游离脯氨酸质量分数、叶绿素质量分数、抗氧化酶活性及光合参数进行测定,并进行主成分分析,对2种种源沙枣的耐盐碱性进行综合评价。结果表明:混合盐碱胁迫时,宁夏种源沙枣的耐盐阈值为1.138%,甘肃种源沙枣的耐盐阈值为1.001%,在综合评分模型中宁夏种源沙枣的综合得分为1.168,甘肃种源沙枣的综合得分为1.011。宁夏种源沙枣对混合盐碱的耐受能力强于甘肃种源沙枣。

With 2-year-old Elaeagnus angustifolia seedlings in Yinchuan,Ningxia and Zhangye and Gansu,four kinds of salt NaCl,Na_(2)SO_(4),NaHCO_(3)and Na_(2)CO_(3)were selected to form mixed saline-alkali(volume ratio of 1∶1∶1∶1,and pH of 9.65).The soil environment of five salt gradients(the contents of salt of 0%,0.3%,0.6%,0.9%and 1.2%)was simulated,and the growth,physical and chemical properties of E.angustifolia were observed under different salt gradients.The molar contents of malondialdehyde,soluble sugar,soluble protein,free proline,chlorophyll,and the activity of antioxidant enzymes and photosynthetic parameters were determined,and the principal component analysis was carried out to comprehensively evaluate the salt and alkaline tolerance of two kinds of Elaeagnus angustifolia.The results showed that under mixed saline-alkali stress,the salt tolerance thresholds of Ningxia provenance and Gansu provenance were 1.138%and 1.001%,respectively.In the comprehensive scoring model,the comprehensive score of Ningxia provenance and Gansu provenance was 1.168 and 1.011,respectively.The tolerance of Ningxia provenance E.angustifolia to mixed salt and alkali was stronger than that of Gansu provenance E.angustifolia.