摘要
采用盆栽控制试验,研究了土壤不同NaCl浓度（0（CK）、1‰、2‰、3‰、4‰、5‰和6‰）处理45 d对四季竹叶片脱落率和细胞膜透性以及立竹器官K^＋、Na^＋、Ca^2＋和Cl^-等矿质离子的吸收、运输和分配的影响。结果表明,1‰-2‰NaCl处理对四季竹叶片脱落率和离子渗漏率无显著影响,3‰-6‰NaCl处理显著提高了叶片脱落率和离子渗漏率,四季竹的盐胁迫伤害随土壤盐浓度的增大而加剧。随着Na^＋、Cl^-在四季竹立竹各器官中的显著增加,竹根、竹秆、竹枝K＋含量逐渐下降,Ca^2＋含量变化较小,并且K^＋、Ca^2＋在竹根、竹秆中的向上选择性运输能力逐渐减弱。由于竹叶在低浓度（1‰-2‰）和高浓度（3‰-6‰）盐胁迫下分别对Ca^2＋和K^＋具有较高的选择性吸收能力,随盐浓度的增大,竹叶K＋含量迅速升高,Ca^2＋含量先升高后下降,这对维持竹叶的营养平衡和正常生长具有重要意义。3‰-6‰NaCl处理时,Na^＋、Cl^-在竹叶中的浓度显著高于立竹其他器官,不仅降低了竹叶的渗透势,有利于水分的向上运输,而且四季竹还可以通过叶片脱落的方式降低体内的盐分含量,减轻盐离子毒害。
A pot experiment was conducted to study the salt-adaptation mechanisms of Oligostachyum lubricum under different soil NaCl stress（0（CK）,1‰,2‰,3‰,4‰,5‰ and 6‰） for 45 days,with the parameters leaf abscission rate,leaf cell membrane permeability,and the uptake,transportation,and allocation of K^＋,Na^＋,Ca^2＋ and Cl^-in different organs investigated.Under 1‰-2‰ NaCl stress,the leaf abscission rate and ion leakage had no significant differences with the control;but under 3‰-6‰ NaCl stress,the leaf abscission rate and ion leakage increased significantly,and the damage increased with increasing soil NaCl concentration.Along with the increasing concentrations of Na＋ and Cl-in the organs of O.lubricum,the K^＋ concentration in root,culm,and branch decreased,Ca^2＋ concentration in the three organs changed slightly,and the transportation of K^＋ and Ca^2＋ from root to culm and from culm to branch slowed down gradually.Due to the stronger selective absorption of K^＋ and Ca^2＋ by leaf under 3‰-6‰ and 1‰-2‰ NaCl stress,respectively,the leaf K^＋ concentration increased rapidly with increasing soil NaCl stress while the leaf Ca^2＋ concentration decreased after an initial increase,being of significance for keeping the ion homeostasis in leaf and maintaining the normal growth of seedlings.The significantly higher concentrations of Na＋ and Cl-in leaf than in other organs under 3‰-6‰ NaCl stress reduced the leaf osmotic potential,being conducive to the upward transportation of water,and also,could mitigate the salt toxicity on O.lubricum via leaf abscission.
出处
《生态学杂志》
CAS
CSCD
北大核心
2011年第7期1417-1422,共6页
Chinese Journal of Ecology
基金
林业公益性行业科研专项(201004008)
杭州市重大科技创新项目(20072312A23)
浙江省省院合作项目(2008SY10)资助
关键词
四季竹
盐胁迫
离子平衡
选择性运输系数
Oligostachyum lubricum
salt stress
ion homeostasis
selective transportation index
作者简介
顾大形，男，1984年生，硕士研究生。主要从事植物生态学研究，发表论文5篇。E—mail：gudaxing2008@163．com通讯作者E—mail：cslbamboo@126．com
