The ectomycorrhizal fungus (Paxillus involutus) modulates leaf physiology of poplar towards improved salt tolerance
The ectomycorrhizal fungus (Paxillus involutus) modulates leaf physiology of poplar towards improved salt tolerance
复制标题
DOI：
10.1016/j.envexpbot.2011.04.008
复制
发表时间：
2011-09
影响因子：
5.7
通讯作者：
Zhi-Bin Luo;Ke Li;Y. Gai;Cornelia Göbel;H. Wildhagen;Xiangning Jiang;I. Feussner;H. Rennenberg
中科院分区：
文献类型：
--
作者：
Zhi-Bin Luo;Ke Li;Y. Gai;Cornelia Göbel;H. Wildhagen;Xiangning Jiang;I. Feussner;H. Rennenberg
外生菌根（EM）是土壤真菌和植物根部之间的共生关系。尽管物理相互作用仅发生在根部，但菌根可能会改变整个植物的生理机能，导致宿主对非生物胁迫的反应发生变化。为了阐明盐胁迫下外生菌根真菌对叶片生理和性能的影响，我们分析了白杨杨叶片中营养元素、植物激素、碳水化合物、氨基化合物和脂肪酸的水平。在存在或不存在卷曲柱霉的情况下以及施加或不施加 150 mM NaCl 盐胁迫的情况下栽培杨树。与非外生菌根植物相比，外生菌根植物的叶子表现出更高的光化学量子产率（ΦPSII）、更高的磷和钾浓度、更低的半乳糖浓度、更高的胁迫代谢物γ-氨基丁酸浓度以及更低的不饱和与饱和脂肪酸比率。盐胁迫导致P.×canes叶片失绿和脱落，ΦPSII、K+与Na+比值、9Z-十六碳烯酸、9Z-十八碳烯酸和不饱和与饱和脂肪酸比值降低，ABA、葡萄糖、果糖和一些氨基化合物含量增加。与非菌根植物相比，在盐度下，外生菌根植物的叶片表现出叶片失绿现象减轻、水分状况改善、ΦPSII和K+与Na+比率更高、主要氨基化合物积累更少、不饱和脂肪酸与饱和脂肪酸比率更低。这些结果表明，外生菌根减轻了盐度引起的黑松叶损伤，这可能归因于外生菌根植物叶子中营养状况、渗透压调节和脂肪酸组成的改善。
Ectomycorrhizas (EMs) are mutualistic associations between soil fungi and plant roots. Although the physical interaction occurs only in roots, mycorrhizas may alter the physiology of the whole plant, resulting in changes in host responses to abiotic stress. To elucidate the influence of an ectomycorrhizal fungus on leaf physiology and performance under salt stress, we analysed the levels of nutrient elements, phytohormones, carbohydrates, amino compounds and fatty acids in leaves ofPopulus×canescens.The poplars were cultivated either in the presence or absence ofPaxillus involutusand either with or without salt stress imposed by 150 mM NaCl. Leaves of ectomycorrhizal plants displayed higher quantum yield of photochemistry (ΦPSII), increased concentrations of phosphorus and potassium, decreased concentrations of galactose, increased concentrations of the stress metabolite γ-amino butyric acid and a lower unsaturated-to-saturated fatty acid ratios than those of non-ectomycorrhizal plants. Salt exposure ofP.×canescensled to leaf chlorosis and shedding, decreases inΦPSII, K+-to-Na+ratio, 9Z-hexadecenoic acid, 9Z-octadecenoic acid and unsaturated-to-saturated fatty acid ratio, and increases in ABA, glucose, fructose and some amino compounds. Under salinity leaves of ectomycorrhizal plants showed an alleviation of leaf chlorosis, improved water status, higher ΦPSIIand K+-to-Na+ratio, less accumulation of major amino compounds and lower unsaturated-to-saturated fatty acid ratios than those of non-mycorrhizal plants. These results indicate that ectomycorrhizas attenuate salinity induced injury in leaves ofP.×canescens, which may be ascribed to the improved nutrient status, osmo-regulation and changes in fatty acid composition in leaves of ectomycorrhizal plants.