论文部分内容阅读
【目的】筛选能够耐受苹果根系自毒物质根皮苷的细菌,研究不同种植年限苹果(Malus Mill.)根际可培养根皮苷耐受菌的微生物群落组成及多样性,旨在为筛选高效根皮苷降解菌、一定程度上了解苹果连作障碍机制并克服或减轻其造成的损失提供科学依据。【方法】以根皮苷为唯一碳源,筛选不同种植年限的根皮苷耐受细菌,通过ARDRA酶切聚类(Amplified r DNA restriction analysis)和16S r RNA基因序列分析确定分离的根皮苷耐受菌的分类地位,并利用生物信息学分析根皮苷耐受菌群落结构、多样性及与理化因子的关系。【结果】从种植年限为3、8、15、20和25年的苹果砧木山荆子[Malus baccata(Linn.)Borkh.]根际土壤中共分离103株根皮苷耐受菌,并在65%的相似水平上分成18个类群,分属于13个属,其优势菌分别为芽孢杆菌属(Bacillus)、假单胞菌属(Pseudomonas)和新鞘脂杆菌属(Novosphingobium)。分析发现种植年限为3年的根际土壤中分离的根皮苷耐受菌的物种丰富度最高,种植年限为15、20和25年的根际土壤中分离的根皮苷耐受菌的物种组成相似,且不同种植年限土壤的理化因子与根皮苷耐受菌的群落组成具有一定的相关性(P<0.05)。冗余分析(Redundancy analysis,RDA)表明阿魏酸是影响群落结构的重要因子。【结论】不同种植年限苹果根际土壤中根皮苷耐受菌种类多样性丰富,其群落组成与土壤理化因子具有一定相关性,阿魏酸是影响根皮苷耐受菌群落结构的重要环境因子。研究结果可为探讨缓解苹果连作障碍的途径提供基础资料。
【Objective】 The objective of this study was to screen for bacteria that could tolerate phlorizin, an autotoxic material of apple root, to study the microbial community composition and diversity of cultivated phlorizin tolerant rhizosphere in different planting years of apple (Malus Mill.), Highly efficient phlorizin degradation of bacteria, to some extent understand the mechanism of continuous cropping obstacles and to overcome or mitigate its losses provide a scientific basis. 【Method】 Phloridin-resistant bacteria were screened for different planting years with phloridzin as the sole carbon source. The isolated phlorizin was determined by Amplified r DNA restriction analysis and 16S rRNA gene sequence analysis. Tolerant bacteria taxonomic status, and bioinformatics analysis of phlorizin tolerance bacteria community structure, diversity and the relationship between physical and chemical factors. 【Result】 A total of 103 phlorizin tolerant bacteria were isolated from rhizosphere soils of apple rootstocks Malus baccata (Linn.) Borkh. Which were planted for 3, 8, 15, 20 and 25 years. % Of the similar level is divided into 18 groups, belonging to 13 genera, the dominant bacteria were Bacillus, Pseudomonas (Pseudomonas) and the new Phosphorus genus (Novosphingobium). It was found that the species rich in phlorizin-tolerant bacteria isolated from rhizosphere soil with the planting years of 3 years had the highest species richness, the species of phlorizin-tolerant bacteria isolated from the rhizosphere soil with the planting years of 15, 20 and 25 years The physical and chemical factors of soil with different planting years were related to the composition of phlorizin tolerant bacteria (P <0.05). Redundancy analysis (RDA) showed that ferulic acid was an important factor affecting community structure. 【Conclusion】 There is a rich diversity of phlorizin tolerance bacteria in rhizosphere soil of different planting years, and the community composition has some correlation with soil physico-chemical factors. Ferulic acid is an important environmental factor affecting the structure of phorbol-tolerant bacteria . The results provide the basic information for exploring the ways to alleviate the cropping obstacle in apple.