钾抑制盐生植物生长的生理基础研究

THE PHYSIOLOGICAL BASIS OF GROWTH INHIBITION OF HALOPHYTES BY POTASSIUM

盐生植物碱蓬（Ｓｕａｅｄａ ｓａｌｓａ）、中亚滨藜（Ａｔｒｉｐｌｅｘ ｃｅｎｔｒａｌａｓｉａｔｉｃａ）和补血草（Ｌｉｍ ｏｎｉｕｍ ｂｉ－ｃｏｌｏｒ）幼苗用不同浓度ＫＣｌ和等渗的ＮａＣｌ处理，结果表明，１００—５００ 和１００—４００ ｍ ｍ ｏｌ／ＬＫＣｌ对它们的有机干重和净光合率产生明显抑制作用，证明Ｋ＋ 可抑制盐生植物生长并与光合速率降低有关。１００—４００ ｍ ｍ ｏｌ／ＬＫＣｌ降低幼苗Ｎａ＋ 而增大Ｋ＋ 含量，对细胞渗透势和渗透调节能力基本不起作用，证明Ｋ＋ 抑制生长与植物体渗透调节物质Ｎａ＋ 不足以及高浓度的Ｋ＋ 对细胞产生毒害有关。还证明盐胁迫使生长和光合速率降低与叶片含糖量无直接关系。另外。

Salt dilution halophyte Suaeda salsa, salt secretory halophytes Atriplex centralasiatica and Limonium bicolor were treated with different concentrations of KCl and isosmotic NaCl. It was found that the organic dry weight and net photosynthetic rate of these plants were inhibited by 100—500 and 100—400 mmol/L KCl respectively, indicating the existance of a relationship between the growth inhibition by K + and the decrease of photosynthesis in halophytes. After treatment with 100—400 mmol/L KCl, the content of K + increased while that of Na + decreased, but there were no change in osmotic potential and ability of osmotic adjustment. It proved that growth inhibition by K + was related to Na + deficiency in osmotic adjustment and the toxic effect of high K + on cells. Further there was no direct relation between the decrease of growth and photosynthesys and the content of sugars in leaves. Moreover, the inhibition of ATPase activity by high K + concentration was probably related to growth inhibition.