土壤盐碱胁迫对春小麦K^+、Na^+选择性吸收的影响

Study on K^+、Na^+ selective absorption of different organs of spring wheat under soil saline sodic stress in different growth season

通过对 2种浓度土壤盐分胁迫下春小麦各品种不同时期各器官 K+、Na+含量以及K+ /Na+的变化及其与抗盐性的关系研究 ,结果表明 ,随土壤盐浓度的升高 ,各品种的产量及各农艺性状值均有所下降 ,但不同品种的下降程度不同。随土壤盐浓度的升高 ,植株中 K+ 、Na+ 含量均有所增加 ,但 K+ 增加的幅度小于 Na+ 的增加幅度 ,因而 K+ /Na+ 呈明显下降趋势 ;在不同土壤盐分胁迫下 ,小麦品种 K+、Na+随生育进程在体内各器官的分配发生动态变化 ,在分蘖期地上部 K+ /Na+ >根部 ,孕穗期各器官 K+ /Na+ 依次为 :幼穗 >旗叶 >茎 >倒 4叶 ,而灌浆期则依次为 :籽粒 >旗叶 >茎 >倒 4叶 ,说明生长旺盛的器官拒 Na+能力强于其它器官 ;不同品种的 K+ 、Na+ 含量及 K+ /Na+ 不同 ,一般抗盐性强的品种在各时期均具较高的K+ /Na+ ,反之则 K+ /Na+ 较低 ;小麦的籽粒产量在一定范围内与其植株地上部各器官的K+ /Na+ 呈一定的正相关 ,其中与分蘖期植株地上部的 K+ /Na+ 及叶 (K+ /Na+ ) /根 (K+ /Na+ )呈极显著正相关 ,而与此时期的 SNa+ K+ 相关性最强 ,r为 - 0 .96 70。因而 ,以分蘖期的K+ /Na+ 尤其是 SNa+ K+ 作为小麦田间抗盐性的指标 ,具有一定的可靠性。

The experiment were conducted to study the relation between salt resistance and the transformation of K + content?Na + content,K /Na + ratio of different spring wheat genotypes under two different soil salt concentration at different stage.The result showed that the yield and the average value of different agronomic characters dropped along with the increasing of soil salt concentration,but different genotypes had different responses.The K + content and Na + content increased while the K +/Na + ratio descended significantly because the increasing scope of K + content was lower than that of Na + content;The distribution of K + content and Na + content in spring wheat genotypes were changed according to different growth season,the K +/Na + ratio of shoot was higher than that of root in tillering stage.In booting stage,the sorting sequence of K +/Na + ratio was young spike,flag leaf>straw>the 4th leaf from top,in grouting stage,K +/Na + ratio of seed was bigger than that of flag leaf while K +/Na + ratio of flag leaf was bigger than that of straw was bigger than that of the 4th leaf from top.The result above showed that the ability of resistant to salt of vigorous organ was stronger than the other organs.In general,salt resistant genotypes had higher K +/Na + ratio.The correlation between the yield of wheat and the K +/Na + ratio was positive at 1% level in certain distance,especially with S Na + K + in tillering stage.The correlation between yield and the leaf (K +/Na +)/root(K +/Na +) was also positive at 5% level.So the K +/Na + ratio in tillering stage,especially S Na + K +,could be treated as salt-resistant index in field experiment.