北京市杨树人工林微生物区系分析

选取107杨、108杨和毛白杨3种杨树人工林,采用分子生物学鉴定方法对人工林中叶面、皮部和土壤中可培养的微生物的数量变化和优势种群动态变化进行分析。结果表明:细菌的数量在107杨与108杨、107杨与毛白杨之间的差异均显著,而在108杨与毛白杨之间的差异不显著;叶面、皮部和土壤的细菌数量差异均显著,107杨夏季和秋季的细菌数量占有优势地位,毛白杨冬季和春季的细菌数量占有优势地位;107杨秋季的细菌数量最高,108杨和毛白杨的较低,季节变化直接影响着细菌数量的变化,是细菌区系变化的主要影响因素;细菌的优势种群以假单胞菌和芽孢杆菌等为主;真菌的数量在107杨与108杨、107杨与毛白杨之间的差异均显著,而在108杨与毛白杨之间的差异不显著,这与细菌的变化规律相似;秋季真菌的数量与其他3季相比差异显著;季节的变化对叶面真菌数量的影响相对较大,而对皮部真菌数量的变化影响相对较小;季节变化对土壤中真菌数量的变化有显著影响,但在春季和秋季差异不大;真菌的优势种群以杨盘二孢菌和棘壳孢等为主,其中棘壳孢在杨树人工林的叶面、皮部和土壤中均占有较高比例,是杨树人工林中真菌的主要类群。

Investigation on Microflora of Poplar Plantations in Beijing

Microflora was investigated by collecting and culturing micro-organisms from the leaves, bark and soil in Populus × euramericana cv. 'Neva', P. × euramericana cv. ' Guariento' and P. tomentosa poplar plantations in this study. Firstly, preliminary results indicated that the total quantity of bacteria in P. × euramericana cv. ' Neva' plantation was remarkably different from that in the P. × euramericana cv. ' Guariento' and the P. tomentosa, and that on difference was found between the latter two. There were significant differences in bacteria quantity from the leaves, bark and the soil. The quantity of bacteria in P. × euramericana cv. ' Neva' plantation was the greatest in summer and autumn, while it in P. tomentosa plantation was the greatest in winter and spring. The total quantity of bacteria was the most in P. × euramericana cv. ' Neva', and more than that in P. × euramericana cv. ' Guariento' and P. tomentosa. The dominant spaces of bacteria were Pseudomonas sp. and Bacillus sp. and so on, which were widely distributed in the four interfaces of the three poplar plantations. Secondly, the variation of the quantity of fungi in the three poplar plantations had the same pattern as bacteria' s. The quantity of fungi was remarkably different between autumn and the other three seasons. The dominant species of fungi were Marssonina sp.,Prenochaeta sp. and Paecilomyces sp. in the poplar plantations.