Department of Bioproducts and Biosystems Engineering, University of Minnesota, St. Paul, MN 55108, USA.
FEMS Microbiol Ecol. 2012 Jan;79(1):109-17. doi: 10.1111/j.1574-6941.2011.01201.x.
Many wood-degrading fungi colonize specific types of forest trees, but often lack wood specificity in pure culture. This suggests that wood type affects competition among fungi and indirectly influences the soil residues generated. While assessing wood residues is an established science, linking this information to dominant fungal colonizers has proven to be difficult. In the studies presented here, we used isolate-specific quantitative PCR to quantify competitive success between two distinct fungi, Gloeophyllum trabeum and Irpex lacteus, brown and white rot fungi, respectively, colonizing three wood types (birch, pine, oak). Ergosterol (fungal biomass), fungal species-specific DNA copy numbers, mass loss, pH, carbon fractions, and alkali solubility were determined 3 and 8 weeks postinoculation from replicate wood sections. Quantitative PCR analyses indicated that I. lacteus consistently outcompeted G. trabeum, by several orders of magnitude, on all wood types. Consequently, wood residues exhibited distinct characteristics of white rot. Our results show that competitive interactions between fungal species can influence colonization success, and that this can have significant consequences on the outcomes of wood decomposition.
许多木质降解真菌定殖于特定类型的森林树木，但在纯培养中往往缺乏木质特异性。这表明木材类型会影响真菌之间的竞争，并间接地影响产生的土壤残留物。虽然评估木材残留物是一项成熟的科学，但将这些信息与优势真菌定殖者联系起来已被证明是困难的。在本研究中，我们使用分离物特异性定量 PCR 来量化两种不同真菌（Gloeophyllum trabeum 和 Irpex lacteus）在三种木材类型（桦木、松木、橡木）上的竞争成功，这两种真菌分别是棕色和白色腐朽真菌。在接种后 3 和 8 周，从重复的木块上测定麦角固醇（真菌生物量）、真菌种特异性 DNA 拷贝数、质量损失、pH 值、碳分数和碱溶性。定量 PCR 分析表明，在所有木材类型上，I. lacteus 始终对数个数量级地超过 G. trabeum 进行竞争。因此，木材残留物表现出明显的白色腐朽特征。我们的结果表明，真菌种间的竞争相互作用会影响定殖成功，这可能对木材分解的结果产生重大影响。
