黄顶菊入侵对土壤磷细菌多样性的影响

采用选择性培养基和rep-PCR聚类分析等手段,通过盆栽试验,研究了入侵植物黄顶菊对土壤中磷细菌多样性的影响。结果表明,黄顶菊入侵后增加了土壤中无机磷和有机磷细菌的数量,入侵后其数量分别为入侵前的1.17倍和1.08倍。rep-PCR基因指纹分析结果显示,黄顶菊入侵前土壤磷细菌包含19个聚类群,其中无机磷细菌10个聚类群,有机磷细菌9个聚类群;入侵后土壤磷细菌包含22个聚类群,其中无机磷细菌11个聚类群,有机磷细菌11个聚类群。多样性分析结果表明,黄顶菊入侵后土壤中无机磷细菌的丰富度指数、香农-威纳多样性指数分别为11和2.369,高于入侵前的10和2.303;有机磷细菌的丰富度指数、香农-威纳多样性指数分别为11和2.398,高于入侵前的9和2.197,而2种细菌的物种均匀度指数基本不变。本文从土壤微生态学的角度初步探讨了黄顶菊入侵对土壤微生物群落中磷细菌的影响,为进一步研究黄顶菊入侵的地下化感机制和竞争机制提供一定的理论依据。

Effects of Flaveria bidentis Invasion on the Diversity of Phosphorus Bacteria in Soil

Flaveria bidentis is a severe invasive plant in North China. The invasion and spread mechanism of this plant have become research hotspots in recent years. In this paper, the effects of F. bidentis invasion on the diversity of phosphorus bacteria in the soil were studied by selective media separation method and rep-PCR fingerprints cluster analysis. The results showed that the amount of inorganic phosphorus bacteria and organic phosphorus bacteria increased by 1.17 times and 1.08 times, respectively. Based on the rep-PCR fingerprints cluster analysis, the phosphorus bacteria was divided into 19 clusters from the control soil, including 10 inorganic phosphorus bacteria and 9 organic phosphorus bacteria clusters. 22 phosphorus bacteria clusters, including 11 inorganic phosphorus bacteria and 11 organic phosphorus bacteria clusters, were obtained from the soil in which F. bidentis was planted. The indices of diversity, richness and evenness of the two kinds of phosphorus bacteria in F. bidentis invaded soils were all higher than those of non-invaded soils. It was demonstrated that the quantity and variety of phosphorus bacteria in invaded soils were both more abundant. This research preliminarily studied the effects of F. bidentis on phosphorus bacteria and provided certain theoretical basis for demonstrating the microecology mechanism of the invasive plant F. bidentis.