Botanical Institute, University of Basel, Hebelstrasse 1, CH-4056 Basel, Switzerland.
New Phytol. 2010 Jan;185(1):67-82. doi: 10.1111/j.1469-8137.2009.03058.x. Epub 2009 Oct 23.
Arbuscular mycorrhizal (AM) fungi form symbiotic associations with the roots of most plants, thereby mediating nutrient and carbon fluxes, plant performance, and ecosystem dynamics. Although considerable effort has been expended to understand the keystone ecological position of AM symbioses, most studies have been limited in scope to recording organism occurrences and identities, as determined from morphological characters and (mainly) ribosomal sequence markers. In order to overcome these restrictions and circumvent the shortcomings of culture- and phylogeny-based approaches, we propose a shift toward plant and fungal protein-encoding genes as more immediate indicators of mycorrhizal contributions to ecological processes. A number of candidate target genes, involved in the uptake of phosphorus and nitrogen, carbon cycling, and overall metabolic activity, are proposed. We discuss the advantages and disadvantages of future protein-encoding gene marker and current (phylo-) taxonomic approaches for studying the impact of AM fungi on plant growth and ecosystem functioning. Approaches based on protein-encoding genes are expected to open opportunities to advance the mechanistic understanding of ecological roles of mycorrhizas in natural and managed ecosystems.
丛枝菌根 (AM) 真菌与大多数植物的根形成共生关系，从而介导养分和碳通量、植物性能和生态系统动态。尽管人们已经付出了相当大的努力来理解 AM 共生的关键生态地位，但大多数研究的范围仅限于记录生物体的出现和身份，这些生物体是根据形态特征和（主要）核糖体序列标记确定的。为了克服这些限制并避免基于培养和系统发育的方法的缺点，我们建议转向植物和真菌的蛋白质编码基因，作为更直接的指标，表明菌根对生态过程的贡献。提出了一些涉及磷和氮吸收、碳循环和整体代谢活性的候选靶基因。我们讨论了未来蛋白质编码基因标记和当前（系统发育）分类学方法研究 AM 真菌对植物生长和生态系统功能影响的优缺点。基于蛋白质编码基因的方法有望为深入了解菌根在自然和管理生态系统中的生态作用提供机会。
