Nguyen H, Calvo Polanco M, Zwiazek J J
Department of Renewable Resources, University of Alberta, 4-42 Earth Sciences Bldg., Edmonton, AB, T6G 2E3, Canada.
Plant Biol (Stuttg). 2006 Sep;8(5):646-52. doi: 10.1055/s-2006-924106. Epub 2006 Jun 1.
Black spruce (PICEA MARIANA), white spruce (PICEA GLAUCA), and jack pine (PINUS BANKSIANA) seedlings were inoculated with HEBELOMA CRUSTULINIFORME or LACCARIA BICOLOR and subjected to NaCl and Na (2)SO (4) treatments. The effects of ectomycorrhizas on salt uptake, growth, gas exchange, and needle necrosis varied depending on the tree and fungal species. In jack pine seedlings, ectomycorrhizal (ECM) fungi reduced shoot and root dry weights and in the ECM white spruce, there was a small increase in dry weights. Sodium chloride treatment reduced net photosynthesis and transpiration rates in the three studied tree species. However, NaCl-treated black spruce and jack pine colonized by H. CRUSTULINIFORME maintained relatively high photosynthetic and transpiration rates and needle necrosis of NaCl-treated black spruce seedlings was reduced by the ECM fungi. Higher concentrations of Na (+) were found in shoots compared with roots of the three examined conifer species. ECM fungi reduced the concentrations of Na (+) mainly in the shoots and this reduction was greater in plants treated with NaCl compared with Na (2)SO (4). Shoots contained generally higher concentrations of Cl (-) compared with roots. In the NaCl-treated black spruce and white spruce, both ECM species significantly reduced Cl (-) concentrations. Our results point to overall greater phytotoxicity of NaCl compared with Na (2)SO (4) and support our earlier findings which demonstrated beneficial effects of ECM fungi for woody plants exposed to NaCl stress.
黑云杉（PICEA MARIANA）、白云杉（PICEA GLAUCA）和短叶松（PINUS BANKSIANA）幼苗接种了硬皮豆马勃（HEBELOMA CRUSTULINIFORME）或双色蜡蘑（LACCARIA BICOLOR），并进行了氯化钠和硫酸钠处理。外生菌根对盐吸收、生长、气体交换和针叶坏死的影响因树种和真菌种类而异。在短叶松幼苗中，外生菌根（ECM）真菌降低了地上部和根部的干重，而在ECM白云杉中，干重略有增加。氯化钠处理降低了三种研究树种的净光合速率和蒸腾速率。然而，接种硬皮豆马勃的经氯化钠处理的黑云杉和短叶松保持了相对较高的光合速率和蒸腾速率，ECM真菌减少了经氯化钠处理的黑云杉幼苗的针叶坏死。在所研究的三种针叶树种中，地上部的钠（Na⁺）浓度高于根部。ECM真菌主要降低了地上部的Na⁺浓度，与硫酸钠处理的植物相比，氯化钠处理的植物中这种降低幅度更大。地上部的氯（Cl⁻）浓度通常高于根部。在经氯化钠处理的黑云杉和白云杉中，两种ECM真菌均显著降低了Cl⁻浓度。我们的结果表明，与硫酸钠相比，氯化钠的总体植物毒性更大，并支持我们早期的研究结果，即ECM真菌对暴露于氯化钠胁迫的木本植物具有有益作用。
