Adriaensen Kristin, Van Der Lelie Daniël, Van Laere André, Vangronsveld Jaco, Colpaert Jan V
Centre of Environmental Sciences, Environmental Biology Group, Limburgs Universitair Centrum, Universitaire Campus, B-3590 Diepenbeek, Belgium.
Brookhaven National Laboratory, Biology Department, Building 463, Upton, New York 11973-5000, USA.
New Phytol. 2004 Feb;161(2):549-555. doi: 10.1046/j.1469-8137.2003.00941.x. Epub 2003 Dec 1.
• Here we investigated zinc tolerance of ectomycorrhizal Scots pine (Pinus sylvestris) seedlings. An ectomycorrhizal genotype of Suillus bovinus, collected from a Zn-contaminated site and showing adaptive Zn tolerance in vitro, was compared with a nonadapted isolate from a nonpolluted area. • A dose-response experiment was performed. Dynamics of plant and fungal development, and phosphate and ammonium uptake capacity, were assessed under increasing Zn stress. Effects of Zn on transpiration, nutrient content and Zn accumulation were analysed. • Significant Zn-inoculation interaction effects were observed for several responses measured, including uptake rates of phosphate and ammonium; phosphorus, iron and Zn content in shoots; transpiration; biomass of external mycelia; and fungal biomass in roots. • The Zn-tolerant S. bovinus genotype was particularly efficient in protecting pines from Zn stress. The growth of a Zn-sensitive genotype from a normal wild-type population was inhibited at high Zn concentrations, and this isolate could not sustain the pines' acquisition of nutrients. This study shows that well adapted microbial root symbionts are a major component of the survival strategy of trees that colonize contaminated soils.
• 在此，我们研究了外生菌根欧洲赤松（Pinus sylvestris）幼苗的耐锌性。将从锌污染场地采集的、在体外表现出适应性锌耐受性的牛肝菌（Suillus bovinus）外生菌根基因型，与来自未污染地区的非适应性分离株进行了比较。
• 进行了剂量反应实验。在锌胁迫增加的情况下，评估了植物和真菌的发育动态以及磷酸盐和铵的吸收能力。分析了锌对蒸腾作用、养分含量和锌积累的影响。
• 对于所测量的几种反应，包括磷酸盐和铵的吸收速率、茎中的磷、铁和锌含量、蒸腾作用、外部菌丝体的生物量以及根中的真菌生物量，观察到了显著的锌接种交互作用效应。
• 耐锌的牛肝菌基因型在保护松树免受锌胁迫方面特别有效。来自正常野生型群体的锌敏感基因型的生长在高锌浓度下受到抑制，并且这种分离株无法维持松树对养分的获取。这项研究表明，适应性良好的微生物根共生体是在受污染土壤中定殖的树木生存策略的主要组成部分。
