多胺对盐胁迫下黄瓜(Cucumis sativus L.)幼苗体内K^+、Na^+和Cl^-含量及器官间分布的影响  

Effects of polyamines on K^+,Na^+ and Cl^-contents and distribution in different organs of cucumber (Cucumis sativus L.) seedlings under NaCl stress

作　　者：王素平[1] 贾永霞[1] 郭世荣[1] 周国贤[1] 

机构地区：[1]南京农业大学园艺学院,南京210095

出　　处：《生态学报》2007年第3期1122-1129,共8页Acta Ecologica Sinica

基　　金：国家高等学校博士点科研基金资助项目(20050307031);江苏省农业三项工程资助项目(SX(2005)088)~~

摘　　要：采用营养液水培,选用耐盐性不同的两个黄瓜品种,研究了外源多胺(Put、Spd、Spm)对NaCl胁迫下黄瓜幼苗植株不同器官中K+、Na+和Cl-含量的影响。结果表明,NaCl胁迫后黄瓜植株体内K+含量下降、Na+和Cl-含量升高、K/Na比值降低,耐盐性较弱的“津春2号”体内离子含量变化幅度明显大于耐盐性较强的“长春密刺”;叶面喷施多胺抑制了K+含量的降低,减少了Na+和Cl-的积累,提高了K/Na比值及K+、Na+吸收和运输的选择性,可缓解盐胁迫的伤害,增加生物积累量,且Spd(亚精胺)的作用尤为明显。总之,外源多胺可通过调控盐胁迫下植株体内的离子平衡,提高黄瓜幼苗的耐盐性。The results showed that K^＋ content decreased while Na^＋ and Cl^-contents increased in salt-treated cucumber seedlings, so the ratios of K/Na and Cl/Na all decreased. The difference in K＋, Na＋ and Cl-contents and the K/Na and Cl/Na ratios was greater for the salt susceptible cv. ＇Jinchun No.2’ than for the salt tolerant cv. ＇Changchun Mici’. Sodium ion content increased significantly in all of organs. Furthermore, Na＋ accumulated primarily in lower leaves, rootstem transition zone and stem. The chloride ion at the organ level, which was one of their major salt-tolerance mechanisms. The accumulation of Na^＋ in the leaves and roots relative to the control was greater than that for Cl - indicating that Na^＋ might be the major toxic ion. Cucumber seedlings treated with exogenous polyamines combined with salinity showed higher levels of K^＋ accumulation and lower levels of Na^＋ and Cl^- accumulation compared with the seedlings treated with salt stress only. Among the three kinds of polyamines, Spd and Spm were more effective in inhibiting the accumulation of Na^＋ and reduction of K ^＋ , however, Put was more effective in reducing Cl^ - accumulation. Furthermore, all of the three kinds of exogenous polyamines could increase the ratio of K/Na, improve the absorbing selectivity of K^＋ to Na＋. Exogenous polyamines improved the transporting selectivity of K^＋ to Na^＋ from stem to leaves for both cultivars. In addition, exogenous polyamines enhanced the transporting selectivity of K^＋ to Na^＋ from root to stem of ＇ Changchun Mici ＇. Exogenous polyamines had no significant effect on the transporting selectivity of Cl^ - to Na^＋ from stem of Cl^ - to Na^＋ from root to stem. to leaves, however, they improved the transporting selectivity of Cl^ - to Na^＋ from root to stem. In conclusion, exogenous polyamines could alleviate salt damage to some extent, and enhance the accumulation of biomass. Among the three kinds of polyamines, Spd was the more effective. of cucumber seedl

关 键 词：多胺 盐胁迫 黄瓜 离子 分布 

分 类 号：S642.2[农业科学—蔬菜学]