不同覆土基质微生物结构特征研究及其对双孢蘑菇产量的影响

覆土是影响双孢蘑菇产量、质量和出菇整齐度的重要因子，利用现代分子生态学的方法快速、准确地对不同覆土基质微生物结构特征进行检测，以进一步了解微生物群落与双孢蘑菇相互作用关系。测定了不同覆土的理化特性，应用PCR技术对不同覆土材料提取总DNA，扩增细菌16S rDNA和真菌28S rDNA，运用变性梯度凝胶电泳技术对PCR产物进行分析，研究双孢蘑菇不同覆土基质微生物结构特征。结果表明：不同处理的覆土材料微生物群落的基因具有多样性，其中细菌群落基因多样性存在差异，使用纯泥炭与粉碎稻草处理差异最大，相似性仅为62%；通过真菌28S rDNA变性梯度凝胶电泳结果显示，粉碎稻草处理多样性指数最高，达3.576，但随着泥炭比例的提高，覆土处理中真菌群落的多样性相对减少；栽培试验发现，双孢蘑菇子实体形成量、总产量可能与覆土中的真菌群落多样性呈负相关。

Effects of different casing soil on microbial structure characteristics and yield of Agaricus bisporus

The casing soil is an important factor to affect Agaricus bisporus yield, quality, and fruiting uniformity. By using modern molecular ecology rapid and accurate detection of microbial structural characteristics of different casing soils may further know how the microbial community interacts with mushrooms. Physical and chemical properties of different overburden material were detected, and the total DNA were extracted. The bacterial 16S rDNA and fungal 28S rDNA were amplified and analyzed by denaturing gradient gel electrophoresis to investigate microorganism structural features of different casing soils. The results showed the different treatment of casing soils had genetic diversity of the microbial community. The result of bacterial community analysis showed the greatest difference in genetic diversity between the pure peat casing soils and soil mixed with crushed straw, and the similarity was only 62%. The fungal 28S rDNA denaturing gradient gel electrophoresis analysis showed that the diversity index in the casing soil comprising crushed straw was 3.576, being the highest among all treatments. With the increase of peat proportion in the casing soil, the diversity of fungal communities relatively reduced. Cultivation experiment showed that the amount of Agaricus bisporus fruiting body formation and total yield were negatively correlated with the diversity of fungal communities in the casing soil.