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将近年来新建立的分子标记技术——相关序列扩增多态性(sequence-related amplified polymorphism,SRAP)应用于土壤微生物遗传多样性研究。采用22对引物组合对20种植物根际土壤微生物进行了分析,共获得237个扩增位点,其中多态性位点221个,占93.2%。平均每对引物组合的多态位点比例(PPL)、多态信息含量(PIC)、等位基因单体型(Ah)和遗传杂合度(He)分别为93.78%、0.94、18.05和0.92,说明SRAP对根际土壤微生物具有较强的鉴别能力,也反映了本研究中20种不同植物的根际土壤微生物具有丰富的遗传多样性。水稻的2个不同种植地和4个不同发育时期间的根际土壤微生物遗传距离差异极显著,但2个不同水稻品种间的差异不显著。Shannon多样性指数揭示,水稻根际土壤微生物的遗传多样性最低,莴苣的最高。按照非加权类平均法(UPGMA)聚类,在遗传距离0.454的水平上,可将20种植物根际土壤微生物分为三类:第一类是水稻根际土壤微生物,第二类是种植于大棚温室的芹菜根际土壤微生物,第三类为其余18种旱作植物根际土壤微生物。本研究结果证明SRAP是分析土壤微生物遗传多样性的有效手段。
In recent years, the newly established molecular marker technology - related sequence amplified polymorphism (sequence-related amplified polymorphism, SRAP) applied to genetic diversity of soil microorganisms. A total of 237 amplification loci were obtained from 22 rhizosphere soil microbes from 22 plant species, of which 221 were polymorphic (93.2%). The percentage of polymorphic loci (PPL), polymorphism information content (PIC), allele haplotype (Ah) and genetic heterozygosity (He) of each primer combination were 93.78%, 0.94, 18.05 and 0.92, This indicated that SRAP has strong ability to identify rhizosphere soil microorganisms, and also reflects abundant genetic diversity of rhizosphere soil microorganisms of 20 different plants in this study. The genetic distance of rhizosphere soil microorganisms in two different planting areas and four different developmental stages of rice was extremely significant, but there was no significant difference between two different rice cultivars. Shannon diversity index revealed that rice rhizosphere soil microbial genetic diversity of the lowest, the highest lettuce. According to UPGMA clustering, twenty rhizosphere soil microbes of 20 species of plants can be classified into three types at the genetic distance of 0.454: the first type is rhizosphere soil microorganism in rice, the second type is inoculated in Greenhouse greenhouse celery rhizosphere soil microorganisms, the third category for the remaining 18 kinds of dry plant rhizosphere soil microorganisms. The results of this study prove that SRAP is an effective method to analyze the genetic diversity of soil microorganisms.