盐胁迫对青钱柳根部离子分布及幼苗生长的影响  

Effect of NaCl Stress on Ion Distribution in Root and Growth of Cyclocarya paliurus Seedlings

作　　者：姚瑞玲[1] 方升佐[1] 

机构地区：[1]南京林业大学森林资源与环境学院,南京210037

出　　处：《林业科学》2008年第6期66-72,共7页Scientia Silvae Sinicae

基　　金：国家自然科学基金资助项目(30371156);江苏省"高新技术研究计划"项目(BG2006314)资助

摘　　要：在0、1、3和5g·L-1NaCl处理下,采用X-射线微区分析法对安徽黄山、江西九江及云南昆明3个种源青钱柳的幼苗根部离子分布及幼苗生长变化进行分析。结果表明:在3或5g·L-1NaCl胁迫下,根部组织中Na+、Cl-的相对含量增加,K+、Ca2+、Mg2+相对含量降低;随着盐浓度增加,根部表皮和皮层中的Na+含量增加,而Cl-在根部中柱和皮层中的相对含量明显增加,根部组织中的离子失衡,K+/Na+和Ca2+/Na+值减小,Na+/(K++Na++Ca2++Mg2+)值增大;根部组织中K+/Na+值的减小和Cl-的显著增加导致幼苗存活率降低,幼苗叶面积、苗高、地径及生物量增量减少;供试种源幼苗耐盐能力为黄山>昆明>九江,且青钱柳幼苗的耐盐阈值在1g·L-1左右。Ion distribution in the root of Cyclocarya pallurus seedlings of three provenances from Huangshan in Anhui, Jiujiang in Jiangxi and Kunming in Yunnan under 0, 1, 3 and 5 g· L^-1 NaCl stress was measured with the method of X-ray microanalysis. The results showed that under the NaCl stress of 3 and 5 g· L^-1, the relative content of Na^＋ and Cl^- in the root tissues increased, while the relative content of K^＋ , Ca^2 ＋ and Mg^2＋ in the root tissues decreased. With the increasing of salinity, the increase of the relative content of Na^＋ occurred in epidermis and cortex of the root, while the remarkable increase of the relative content of Cl^- occurred in stele and cortex of root. Therefore, the two kinds of ions in root tissues were imbalance. The ratios of K^＋/Na^＋ and Ca^2＋/Na^＋ decreased, and hence Na^＋/（K^＋ ＋ Na^＋ ＋ C^2＋ ＋ Mg^2＋） increased; The decrease in K^＋/Na^＋ ratio and the substantial increase in Cl^- in root tissues would be the factors that reduced the seedling survival and growth in leaf area, height, basal diameter as well as biomass. In preliminary conclusion, the level of salt tolerance of the tested provenances was in an order of Huangshan 〉 Kunming 〉 Jiujiang, and around 1 g· L^-1 was the threshold concentration of salt to which the seedlings were able to tolerate.

关 键 词：盐胁迫 青钱柳 离子分布 根部组织 X-射线微区分析 

分 类 号：S727.34[农业科学—林木遗传育种]