Coupled Shifts in Ectomycorrhizal Communities and Plant Uptake of Organic Nitrogen Along a Soil Gradient: An Isotopic Perspective
Coupled Shifts in Ectomycorrhizal Communities and Plant Uptake of Organic Nitrogen Along a Soil Gradient: An Isotopic Perspective
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外生菌根群落与植物吸收有机氮沿土壤梯度的耦合变化：同位素视角
DOI：
10.1007/s10021-021-00628-6
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发表时间：
2021
期刊：
影响因子：
3.7
通讯作者：
Upchurch, Rima A.
中科院分区：
文献类型：
--
作者：
Pellitier, Peter T.;Zak, Donald R.;Argiroff, William A.;Upchurch, Rima A.
植物与互惠外生菌根(ECM)真菌结合可直接获得土壤有机质(N-SOM)中的氮(N)。然而，在田间条件下，N-SOM对植物生长的贡献仍然很少受到限制。我们验证了这样一种假设，即在低无机氮土壤中，ECM群落沿土壤无机氮梯度的周转调节了植物对N-SOM的依赖，而在无机氮丰富的土壤中，ECM群落主要吸收无机N。我们量化了Q的δ15N。利用分子测序技术研究了海藻群落、与N-觅食相关的形态特征以及聚集型孢子果δ15N。为了支持我们的假设，我们记录了随着土壤无机氮供应的增加，根和叶δ15N的逐渐丰富；随着无机氮供应的增加，绿叶的−在5.95到0.16‰之间。低无机氮土壤中的细胞外基质群落主要是Cortinarius属，其他形成菌丝形态的真菌可能参与了N-SOM的获取；这些群落的孢子果皮估计丰富了(+ 4‰)，进一步支持了真菌N-SOM的获取。相反，生长在高无机氮土壤中的树木拥有不同的群落，其形态特征与无机氮的获取和孢子果的枯竭(+ 0.5‰)有关。总之，我们的结果与在觅食成本和N-SOM对植物生长的贡献方面的明显权衡是一致的，并证明了细胞外基质群落组成、真菌N-觅食潜力和叶片δ15N之间的联系。ECM群落的功能特征代表了植物养分觅食策略灵活性的机制基础。我们得出结论，N-SOM对植物生长的贡献可能取决于ECM群落组成和当地土壤养分的有效性。
Plants associating with mutualistic ectomycorrhizal (ECM) fungi may directly obtain nitrogen (N) bound in soil organic matter (N-SOM). However, the contribution of N-SOM to plant growth under field conditions remains poorly constrained. We tested the hypothesis that turnover in ECM communities along soil inorganic N gradients mediates a functional transition from plant reliance on N-SOM in low inorganic N soils, to primarily inorganic N uptake in inorganic N-rich condition soils. We quantified the δ15N ofQ. rubrafoliage and roots, organic and inorganic soil N pools, and used molecular sequencing to characterize ECM communities, morpho-traits associated with N-foraging, and a community aggregated sporocarp δ15N. In support of our hypothesis, we document the progressive enrichment of root and foliar δ15N with increasing soil inorganic N supply; green leaves ranged from − 5.95 to 0.16‰ as the supply of inorganic N increased. ECM communities inhabiting low inorganic N soils were dominated by the genusCortinarius, and other fungi forming hyphal morphologies putatively involved in N-SOM acquisition; sporocarp estimates from these communities were enriched (+ 4‰), further supporting fungal N-SOM acquisition. In contrast, trees occurring in high inorganic N soils hosted distinct communities with morpho-traits associated with inorganic N acquisition and depleted sporocarps (+ 0.5‰). Together, our results are consistent with apparent tradeoffs in the foraging cost and contribution of N-SOM to plant growth and demonstrate linkages between ECM community composition, fungal N-foraging potential and foliar δ15N. The functional characteristics of ECM communities represent a mechanistic basis for flexibility in plant nutrient foraging strategies. We conclude that the contribution of N-SOM to plant growth is likely contingent on ECM community composition and local soil nutrient availability.
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影响因子：
2.6
作者：
Christian N;Bever JD
通讯作者：
Bever JD
影响因子：
2.2
作者：
D. Zak;K. Pregitzer;G. Host
通讯作者：
G. Host
DOI：
10.1073/pnas.1906655116
发表时间：
2019-11-12
影响因子：
11.1
作者：
Averill, Colin;Bhatnagar, Jennifer M.;Kivlin, Stephanie N.
通讯作者：
Kivlin, Stephanie N.
影响因子：
30.8
作者：
Kohler, Annegret;Kuo, Alan;Martin, Francis
通讯作者：
Martin, Francis
影响因子：
11
作者：
Bodeker, Inga T. M.;Nygren, Cajsa M. R.;Lindahl, Bjorn D.
通讯作者：
Lindahl, Bjorn D.