Abstract: By adopting microbiological culture method and terminal restriction fragment length polymorphism (T-RFLP) technique, this paper analyzed the effects of Pseudostellariae heterophylla continuous cropping on the microbial community structure in the rhizosphere soil. Compared with the rotation system of P. heterophylla-rice-P. heterophylla, the P.heterophylla continuous cropping led to a significant decrease of the amounts of bacteria and aerobic nitrogen-fixing bacteria in rhizospheric soil, but increased the amounts of fungi, actinomycetes, and anaerobic cellulose-decomposing bacteria significantly. No significant change was observed in the amount of nitrifying bacteria. Under P.heterophylla continuous cropping, soil bacterial species (genus) had a slight decrease, in which, the pathogenic and nosogenetic bacteria species (genus) increased, and some Streptomyces genus (species) with antagonistic function were found. The fungi species (genus) had an increasing trend, but none of the plant pathogenic fungi species (genus) was observed.

Key words: Larix chinensis population, Spatial distribution, Clustering pattern type, Scale