生姜茎基腐病病原拮抗细菌的筛选与鉴定

从生姜根际土壤分离得到62个细菌分离物。以姜茎基腐病病原菌(Pythium myriotylum)为指示菌,共选出7株对姜茎基腐病菌有良好拮抗效果的细菌菌株。经过形态学观察、生理生化测定,16S rDNA序列及系统发育分析,结合《常见细菌系统鉴定手册》等,X-11、JK-14、SF-19、SF-23等4株初步鉴定为芽孢杆菌属(Bacillus spp.),JK-19、JK-28、JK-25 3株鉴定为类芽孢杆菌属(Peanibacillus spp.)。SF-19、SF-23、JK-25、JK-19、JK-28、X-11和JK-14的16S rDNA序列的GenBank登录号分别为JQ283970、JQ283971、JQ283972、JQ283973、JQ283974、JQ283975、JQ283976和JQ283977。进一步分析表明,7株拮抗菌对Rhizoctonia solani、Fusarium graminearum、Verticillium dahliae等多种类型的病原真菌有较好的抑制作用;显微观察结果表明,拮抗菌可导致病菌菌丝细胞顶端膨大、菌丝体畸形、分隔增多等变化。

Screening and Identification of Antagonistic Bacteria against Ginger Rhizome Rot Pathogen Pythium myriotylum

Sixty-two bacteria were isolated from the ginger rhizosphere soil and seven showed better antagonistic effects to Pythium myriotylum.According to the results of morphologic characteristics,physiological and biochemical properties and phylogenetic analysis of bacteria 16S rDNA,the strains of X-11,JK-14,SF-19 and SF-23 were preliminary identified as Bacillus spp.,and the strains of JK-19,JK-28 and JK-25 belonged to Peanibacillus spp..The sequences of 16S rDNA of the 7 strains had been submitted to GenBank,and their accession numbers were as follows:SF-19 as JQ283971,SF-23 as JQ283972,JK-25 as JQ283973,JK-19 as JQ283974,JK-28 as JQ283975,X-11 as JQ283976,JK-14 as JQ283977,respectively.All the 7 strains also showed inhibition to Rhizoctonia solani,Fusarium graminearum,Verticillium dahliae and so on.The microscopic examination showed that the antagonistic bacteria could make the hypae cell tip swollen,the mycelia deformed and the compartment increased.