Gobert Anthony, Plassard Claude
Sol & Environnement, UMR 388, Equipe Rhizosphère et Symbioses, AgroM-INRA, 2 Place Viala, Bâtiment 13, 34060 Montpellier Cedex 01, France.
New Phytol. 2002 May;154(2):509-516. doi: 10.1046/j.1469-8137.2002.00378.x.
• A different NO dependent pattern of NO uptake at low [NO ] (0-0.1 mM) is shown in Pinus pinaster and in the ectomycorrhizal fungus Rhizopogon roseolus. In ectomycorrhizal symbiosis, the fungal pattern is pre-eminent. • Net NO uptake rates were deduced in plant and fungus from solution depletion measurements. Net NO fluxes were estimated at the surface of mycorrhizal and nonmycorrhizal short roots, using NO selective microelectrodes. • In NO starved seedlings, maximum NO uptake rates were reached after 3 d of incubation in 0.05 mM NO . In R. roseolus mycelia, NO uptake rates did not change after withdrawing NO for up to 7 d, or after adding NO for 3 d. Net NO fluxes in nonmycorrhizal short roots were increased twofold by a 3-d exposure to NO whereas in ectomycorrhiza they were similar irrespective of the NO pretreatment, but always higher than the fluxes measured in nonmycorrhizal roots. • Ectomycorrhiza have a greater capacity to use NO than nonmycorrhizal short roots, whatever the NO concentration in the solution. This may give mycorrhizal plants a greater ability to use fluctuating concentrations of NO in the soil solution.
• 辐射松和外生菌根真菌玫瑰红根须腹菌在低[NO]（0 - 0.1 mM）时呈现出不同的依赖NO的NO吸收模式。在外生菌根共生中，真菌模式占主导。
• 通过溶液消耗测量推导出植物和真菌中的净NO吸收速率。使用NO选择性微电极估计菌根和非菌根短根表面的净NO通量。
• 在缺NO的幼苗中，在0.05 mM NO中培养3天后达到最大NO吸收速率。在玫瑰红根须腹菌菌丝体中，去除NO长达7天或添加NO 3天后，NO吸收速率没有变化。非菌根短根中的净NO通量通过3天暴露于NO而增加了两倍，而在外生菌根中，无论NO预处理如何，它们都相似，但总是高于在非菌根根中测量的通量。
• 无论溶液中的NO浓度如何，外生菌根比非菌根短根具有更大的利用NO的能力。这可能使菌根植物具有更大的能力来利用土壤溶液中波动的NO浓度。
