栽培苍术根际土壤微生物变化

目的：观察苍术栽培中根际土壤微生物数量和群落结构的变化规律。方法：稀释平板法测定一至二年生栽培苍术根际区土壤微生物群落细菌、真菌、放线菌总量；提取苍术根际区土壤微生物DNA,使用E. coli的27 f和1 492 r引物扩增16S rDNA,Hinf内切酶酶切,比较一至二年生栽培苍术根际区土壤微生物群落结构的变化。结果：二年生苍术根际区土壤中细菌、真菌、放线菌普遍低于一年生样品,三者分别下降46.14%,49.25%,31.88%,土壤细菌、真菌及放线菌三者的比例改变；所有一至二年生的8个样品扩增后均得到重复性好且稳定清晰的16S rDNA条带,片段长度约为1 500 bp。Hinf酶切后多数样品在1 000 bp附近均出现主带,其他弱带不完全相同。就多数样品而言,一年生与二年生苍术根际区土壤样品的酶切谱带在年间变异大于年内的变异。结论：多年栽培苍术病虫害的发生,可能与其根际区土壤微生物数量和群落结构的改变有关。

Change of microbial community in rhizoma sphere of cultivated Atractylodes lancea

OBJECTIVE: To find the development rules of microbial community in rhizoma sphere of the cultivated Atractylodes lancea. METHOD: Total bacteria, fungi and actinomyces were counted by CFU x g(-1) though dilution plate method. And genomic DNA of microbes were extracted and amplified by primers of E. coli's 27f and 1492r to get the 16S rDNA, then the restriction endonuclease Hinf was used to digest the 16S rDNA. RESULT: Total bacteria, fungi and actinomyces in 2-year old soil were lower than in 1-year old soil, they decreased 46. 14%, 49. 25%, 31.88% respectively and made the ratio of themselves changed. At the same time, all the 8 soil samples got fine 16S rDNA bands, which were about 1500 bp. And the main bands of most of the samples were found at 1000 bp, but the weak bands of each were different although most bands in the same year samples were more similar than in different year ones. CONCLUSION: It is indicated that the change of soil microbial community may has some relation to the continous cropping barrier of A. lancea.