从红树植物根际土壤选择性分离小双孢菌

Selective Isolation of Microbispora from Rhizhosphere Soil of Mangrove Plants

摘要:

从海南文昌采集23种红树植物的根际土壤, 采用GA、HV作为选择性分离培养基, 添加复合维生素、放线菌酮、制霉菌素和重铬酸钾, 结合适当的预处理: 干热120°C 60 min或干热100°C 60 min及1% 氯胺-T处理30 min, 平板稀释涂布法(10-1、10-2、10-3)分离其中的小双孢菌。共分离得到199株放线菌, 通过培养特征及显微形态观察, 发现其中有链霉菌147株、非链霉菌52株。选择7株链霉菌和28株非链霉菌进行了16S rRNA基因序列分析, 结果显示19株菌属于小双孢菌属, 7株属于链霉菌属, 4株属于野野村菌属, 2株属于小单孢菌属, 1株属于链孢囊菌属, 1株属于阿萨诺氏菌属, 1株属于小单孢菌科。结果表明红树林根际土壤中蕴含着丰富的小双孢菌资源。

Abstract:

To selectively isolate Microbispora sp. from mangrove, 23 rhizosphere soils of different mangrove plants were collected in Wenchang, Hainan, China. After pretreatments of dry heat (100°C 60 min or 120°C 60 min) and treatment with Chloramine-T (1%, 30 min at room temperature) for each sample, 100 μL of the 10-1~10-3 dilutions of the resultant suspensions were transferred and spread onto the selective isolation media. GA and HV media were employed as the isolation media that supplemented with 0.5 mg/L multi-vitamin, 50 mg/L~100 mg/L K2Cr2O7, 50 mg/L cycloheximide and 50 mg/L nystatin. One hundred and ninety nine actinomycetes including 147 Streptomyces-like isolates and 52 non-Streptomyces-like isolates were isolated according to their morphology on agar plates and under microscope. Seven Streptomyces-like isolates and 28 non-Streptomyces-like isolates were putatively identified to genus level based on 16S rRNA gene sequence analysis, which belong to Microbispora(19), Streptomyces(7), Nonomuraea(4), Micromonospora(2), Streptosporangium(1), Asanoa(1), and one uncertain genus under Micromonosporaceae. It is found that plenty of Microbispora spp. inhabit in mangrove rhizoshere soil.