黄河三角洲盐碱土条件下水稻苗期耐盐指标筛选

摘要

本研究选取黄河三角洲地区的盐碱土,将高盐和低盐土按照不同比例配制成试验用土,在水稻两叶一心期,测定供试12个水稻材料的9个与耐盐相关的形态学和生理学指标,并对其苗期耐盐指标进行筛选.结果表明,在0.34％盐浓度下,水稻苗期的株高、干物质积累等受到抑制,不同材料之间的叶绿素含量、丙二醛含量和抗氧化酶活性差异明显.对各性状测定数据为参数的耐盐指数进行主成分分析,提取出两个综合指标,贡献率分别为55.588％和24.054％,累积贡献率为79.642％.根据D值得出海稻86对盐的耐受性最强,其次为盐粳218、日本晴.通过逐步回归分析建立的最优回归方程表明,幼苗鲜重、叶绿素b含量、超氧化物歧化酶活性、丙二醛含量和株高这5项指标对水稻苗期的耐盐性有显著影响,可作为该地区水稻苗期的耐盐鉴定指标.%The saline alkali soil was collected from the Yellow River Delta.On the basis of analyzing the salt content of the above soils,the artificial soils were prepared by mixing high-and low-salt soils at different ratios.Nine morphological and physiological indexes related to saline-alkali tolerance were determined in 12 rice materials at the stage with two leaves and one shoot.The results showed that the plant height and dry matter accumulation of seedlings were inhibited at the salt concentration of 0.34％,and there were obvious differences in chlorophyll content,malondialdehyde content and antioxidant enzyme activities between different rice materials.The principal component analysis was carried out on the salt tolerance indexes,and two comprehensive indexes were extracted with the contribution rate as 55.588％ and 24.054％ respectively;their cumulative contribution rate was 79.642％.Haidao 86 had the greatest tolerance to salt,followed by Yanjing 218 and Nipponbare.The optimal regression equation was established through step regression analysis,and it showed that fresh weight,chlorophyll b content,superoxide dismutase activity,malondialdehyde content and plant height significantly influenced the saline tolerance of rice seedlings,so they could be as the indexes to identify the salt tolerance of rice seedlings.