Abstract: An antagonistic endophytic bacteria strain 261MY6,after assessing inhibition zones on nutrient media,was identified as having strain antagonistic ability against Pseudomonas Syirnge which causes bacteria spot on tomatoes. This strain was selected from endophytic bacteria strains that isolated from alpine meadow pasture. Based on morphological,physiological and biochemical analysis,plus16S rDNA and gyrB gene sequence analysis,it was identified as Bacillus amyloliquefaciens. The biological characteristics and functions were evaluated by means of plate sputum method,phosphate solubilizing method,Salkowski method and pot experiment. The strain 261MY6 produced a 1.20 cm diameter inhibition zone,and the potting control effect was 68.71%. It has the functions of dissolving nitrogen fixation,phosphorus solubilization,and IAA-producing ability. It also has a good inhibitory effect on the Stysanus stemonitis,Colletotrichum coccodes,Fusarium avenaceum,Bipolaris sorokiniana,F. oxysporum,Botrytis cinerea,Stysanus stemonitis,F. Solani,and Fusarium sp.. These results suggest that further development and utilization of this endophytic bacteria strain 261MY6 should be undertaken.

Key words: Antagonistic bacteria, Screening, Identification, Biological characteristics, Control effect

摘要： 本研究以番茄丁香假单胞叶斑病菌Pseudomonas syringa为指示菌，采用含菌平板抑菌圈测定法，从高寒草甸牧草内生细菌中筛选获取优良拮抗菌株261MY6，结合形态学、生理生化、16S rDNA及gyrB基因序列分析将其鉴定为解淀粉芽孢杆菌（Bacillus amyloliquefaciens）。通过平板对峙法、溶磷法、Salkowski法及盆栽试验等测定其生物功能及室内盆栽防效。结果表明，菌株261MY6对番茄丁香假单胞叶斑病菌的抑菌圈直径达1.20 cm，盆栽防效达68.71%。具有溶解无机磷、固氮和分泌IAA的功能，对马铃薯褐腐病菌（Stysanus stemonitis）、马铃薯炭疽病菌（Colletotrichum coccodes）、马铃薯枯萎病菌（Fusarium avenaceum）、小麦根腐病菌（Bipolaris sorokiniana）、黄瓜枯萎病菌（F. oxysporum）、番茄灰霉病菌（Botrytis cinerea）、马铃薯褐腐病菌（Stysanus stemonitis）、孜然根腐病菌（F. Solani）和番瓜根腐病菌（Fusarium sp.）有良好抑制作用。该结果为解淀粉芽孢杆菌261MY6进一步开发利用提供了理论依据。

关键词: 拮抗细菌, 筛选, 鉴定, 生物学特性, 防效