长白山地区不同采集土样方式筛菌效率比较

目的对随机采样和田字格定点采样两种取样方式筛菌效率进行比较分析。方法利用随机采样和定点采样两种不同方式,采集了长白山地区的土样,取来自不同植物根际的土样,制成菌悬液后煮沸,涂布无氮平板以分离固氮芽胞杆菌。对分离的菌株进行菌落16S rDNA PCR,从中筛选鉴别巨大芽胞杆菌。结果定点采集土样分离出无晶体芽胞菌和有晶体芽胞菌分别是261株和76株,随机采集土样分离出无晶体芽胞菌和有晶体芽胞菌分别是279株和94株。经16S rDNA法鉴定分离巨大芽胞杆菌共19株。结论随机采样的取土方式与定点采样的取土方式差异度小,两种采集土样的方式在筛菌效率上并未表现出明显差异。

A comparison of bacterial isolation efficiency between two different waysof soil sample collection in Changbai Mountain area in Jilin

Abstract: Objective To compare the efficiency of bacteria screening between random sampling and fixed-area plot sampling. Methods Soil samples were collected from the Changbai Mountain area by using random sampling and fixed-area plot sampling.Bacterial suspensions were made with the soil samples from the roots of different plants, and then spreaded on nitrogen-free plates after boiling to separate nitrogen-fixing bacilli. 16S rDNA PCR was used to identifyBacillus megaterium from the separated bacterial strains. The efficiency of screening by using the samples collected with the two sampling methods were compared. Results 261 strains (with parasporal crystal) and 76 strains (without parasporal crystal) of bacilli were isolated from the samples collected with fixed-area plot sampling method, versus 279 and 94 strains from those collected with random sampling method. 19 strains of Bacillus megaterium were identified by using 16S rDNA. Conclusion There is no significant difference between the two sampling methods in the efficiency of bacteria screening.