以东祁连山高寒草地矮生嵩草(Kobresia humilis)内生细菌263AG5为研究对象,采用平板对峙法和Salkowski比色法测定其抑菌和分泌植物生长素(IAA)的能力,并利用形态学和分子生物学方法对其进行鉴定.结果表明:263AG5对马铃薯坏疽病菌(Phomafoveata)和炭疽病菌(Colletotrichum coccodes)均有较好的抑制作用,且具有固氮和产IAA的能力,溶磷量为60.52mg·L-1.263AG5菌体杆状,大小为(0.71~1.78)×(0.27~0.48)μm,呈革兰氏阳性,结合16S rDNA基因序列相似性分析鉴定263AG5为莫海威芽孢杆菌(Bacillus mojavensis),该菌具有开发为微生物农药的潜力.
The studies focused on endophytic bacteria 263AG5 from Kobresia humilis in alpine grassland near the Eastern Qilian Mountains.The methods of dual culture and Salkowski colorimetric were used to determine the antagonistic effect and IAA secretion ability of endophytic bacteria.Strain 263AG5 was identified by morphological and molecular biological methods.The results showed that 263AG5 inhibited the pathogenic fungi of potato,such as Phoma foveata and Colletotrichum coccodes,and had the abilities of nitrogen fixation and IAA secretion.The phosphorus solubilizing ability of 263AG5 was 60.52 mg ·L-1.Endophytic bacteria 263AG5 was rod-shaped with a size of (0.71~1.78) × (0.27~0.48) μm,Grampositive.The sequence analyses of 16S rDNA gene showed that 263AG5 was Bacillus mojavensis.Therefore,263AG5 could be developed as microbial fungicide.