Nitrogen plant-microbial competition

The morphological and physiological dissimilarities between mycorrhizal symbi-o.ses probably determine their success and their distinct patterns in different ecosystems (92). Nitrogen (N) available to both AM and ectomycorrhizal plants should not be regarded as a single pool open to free competition. Specialization of its acquisition and utilization in a given habitat is an important feature of plant and microbial community structure, while the fact that the ability to exploit its sources (and tho.se of other limited nutrients) is not the same in all species may result in niche differentiation (93). If habitat specialization is a reflection of differences between mycorrhizal types, ectomycorrhizal and AM species could cooccur because they exploit different niches in the. same ecosystem. 

Friedel, J.K., Gabel, D. and Stahr, K. 2001. Nitrogen pools and turnover in arable soils under different durations of organic farming II Source-and-sink function of the soil microbial biomass or competition with growing plants Journal of Plant Nutrition and Soil Science-Zeitschriftfur Pflanzenernahrung und Bodenkunde 164 421-429. 

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