中国农业科学 ›› 2009, Vol. 42 ›› Issue (5): 1631-1638 .doi: 10.3864/j.issn.0578-1752.2009.05.016

• 植物保护 • 上一篇    下一篇

与桃树再植病相关的根际微生物的分离鉴定及相互作用

  

  1. 北京农学院植物科学技术学院
  • 收稿日期:2008-06-17 修回日期:2008-09-05 出版日期:2009-05-10 发布日期:2009-05-10
  • 通讯作者: 马焕普

Isolation, Identification and Interaction of Rhizosphere Microorganisms Involved in Peach Replant Diseases

  1. 北京农学院植物科学技术学院
  • Received:2008-06-17 Revised:2008-09-05 Online:2009-05-10 Published:2009-05-10
  • Contact: MA Huan-pu

摘要:

【目的】研究桃树再植病与根际微生物的关系。【方法】以Mфller氰化钾培养基为选择培养基进行桃根际微生物的筛选,采用16S rDNA 序列分析并结合生物学特性对所获菌株进行鉴定,并通过温室盆栽试验对所获拮抗菌的生防效果进行初步观察。【结果】从桃根际土壤中分离筛选出3株能以扁桃苷为碳源产生氢化氰(HCN)的细菌(CN-X4、CN-X9、CN-X17)和3株分别能对上述细菌有不同抑制作用的放线菌(CN-G2、CN-G3、CN-G5)。鉴定结果表明菌株CN-X4、CN-X17均为农杆菌属中的根癌农杆菌(Agrobacterium tumefaciens),但分属不同的变种;菌株CN-X9为假单胞杆菌(Pseudomonas sp.),菌株CN-G2和CN-G5分别为细黄链霉菌(Streptomyces microflavus)、淡紫灰链霉菌(Streptomyces lavendulae),菌株CN-G3可能是灰色链霉菌(Streptomyces griseus)的近缘种;拮抗菌盆栽生防效果显著。【结论】桃根际不仅存在能以扁桃苷为碳源并产生HCN的细菌而且同时存在与其相拮抗的耐氰放线菌,根际微生物区系平衡的破坏是导致再植病的关键因素之一。

关键词: 桃, 再植病, 细菌, 拮抗菌

Abstract:

【Objective】 The objective of this study is to explain the relation of peach replant diseases and rhizosphere microorganisms. 【Method】Peach rhizosphere microorganisms were isolated with Mфller Potassium Cyanide Medium. The isolated strains were identified by 16S rDNA sequences and biological characterization. Biocontrol effect were observed in pot trials initially.【Result】 Three bacteria strains (CN-X4, CN-X9, CN-X17) which could utilize amygdalin as carbon source and produce hydrocyanic acid were separated from peach rhizophere soil, and three rhizosphere actinomyces strains(CN-G2, CN-G3, CN-G5)were also isolated, and show different antagonistic effect on the three bacterial strains by plate bacteriostasis assays. Strain CN-X4 and strain CN-X17 were identified as Agrobacterium tumefaciens, but they were different subspecies. Strains CN-X9, CN-G2 and CN-G5 were proved to belong to Pseudomonas sp, Streptomyces microflavus, Streptomyces lavendulae, respectively. Strain CN-G3 may be close or similar to a species of Streptomyces griseus. Biocontrol effect was significant in pot trials. 【Conclusion】 There were not only bacteria which could utilize amygdalin as carbon source and produce hydrocyanic acid but also actinomyces which had antagonistic effect on the bacteria in peach rhizosphere. The unbalance of the rhizosphere microorganisms is considered as a crucial factor for peach replant diseases occurrence.

Key words: peach, replant disease, bacteria, antagonists