摘要
为了研究盐胁迫条件下营养元素K+、Ca2+和Mg2+对不同自交系玉米耐盐性影响的差异,探讨玉米耐盐胁迫的生理机制,以玉米耐盐自交系81162和8723及盐敏感自交系P138为材料,在盐胁迫条件下(180mmol/L NaCl),提高溶液中Ca2+和Mg2+的含量,比较营养元素K+、Ca2+和Mg2+浓度的变化对不同基因型玉米萌发期和幼苗期耐盐性的影响。结果表明,盐胁迫条件下提高溶液中Ca2+和Mg2+的含量,可显著降低萌发期和幼苗期植株体内Na+含量和Na+/K+、Na+/Ca2+、Na+/Mg2+比,各项萌发指标、生长和生理生化指标都得到明显改善,明显减轻盐胁迫的危害,增强玉米耐盐胁迫能力,且Ca2+处理的效果优于Mg2+处理;提高溶液中K+含量的效果远远小于Ca2+和Mg2+处理,K+对玉米耐盐性的影响相对不明显,不能显著降低植株体内Na+含量和Na+/K+、Na+/Ca2+、Na+/Mg2+比,这也是K+处理对玉米耐盐性影响相对不明显的内在原因。盐胁迫条件下,耐盐自交系(81162和8723)与盐敏感自交系(P138)相比,植株体内有较低的Na+含量和Na+/K+、Na+/Ca2+、Na+/Mg2+比,有较高的K+含量,这些都是耐盐自交系耐盐胁迫能力高于盐敏感自交系的内在原因。因此,K+、Ca2+和Mg2+在植株体内的含量及其与Na+的比值变化都会影响玉米萌发期和幼苗期耐盐性;适当提高玉米生长环境的Ca2+和Mg2+浓度可以明显增强植株耐盐胁迫能力,营养元素Ca2+的效果比Mg2+明显;而K+对玉米耐盐性的影响相对不明显。
Under salt stress,exogenous nutrients（K^＋,Ca^2＋and Mg^2＋）have effect on the salt tolerance of crops,with different salt tolerances between different maize genotypes.In order to further explore the reasons of different salt tolerances between different maize genotypes and to clarify the physiological mechanism of salt tolerance in maize,the salt-tolerant inbred lines 81162 and 8723and the salt-sensitive inbred line P138 were used as experimental objects,to compare the effects of different contents of exogenous nutrients K^＋,Ca^2＋and Mg^2＋on salt tolerance of different maize genotypes at germination and seedling stage.The results showed that under 180mmol/L NaCl stress,when exogenous Ca^2＋and Mg^2＋contents were increased,Na＋content and the ratios of Na＋/K^＋,Na＋/Ca^2＋and Na＋/Mg^2＋in maize plant were obviously reduced at germination and seedling stage,and the indexes related to plant growth,and the physiological and biochemical indexes were clearly improved,meanwhile,the damage of salt stress was obviously reduced,and the salt tolerance of maize was remarkably enhanced at germination and seedling stage,with exogenous Ca^2＋treatments showing better effects compared with Mg^2＋treatments.However,the effects of exogenous K^＋treatments was far smaller than exogenous Ca^2＋and Mg^2＋treatments,and exogenous K^＋treatments could not obviously reduce Na＋content and the ratios of Na＋/K^＋,Na＋/Ca^2＋and Na＋/Mg^2＋,which was the inner reason causing the inapparent effect of K^＋treatments on the salt tolerance of maize.Na＋contents and the ratios of Na＋/K^＋,Na＋/Ca^2＋and Na＋/Mg^2＋in salt-tolerant inbred lines（81162and 8723）were lowerthan those in salt-sensitive inbred line P138 under salt stress,and K^＋contents were higher,which was why the salt tolerance of salt-tolerant inbred lines was higher than that of the salt-sensitive inbred line.Therefore,K^＋,Ca^2＋and Mg^2＋contents and the changes of Na＋/K^＋,Na＋/Ca^2＋and Na＋/Mg^2＋in maize can af
出处
《水土保持学报》
CSCD
北大核心
2015年第4期253-259,共7页
Journal of Soil and Water Conservation
基金
国家自然科学基金项目(31260330,31301333)
教育部博士点基金项目(20126202120001)
甘肃省高等学校科研项目(2013B-037)
