ABSTRACT

Allelochemicals exuded by Stellera chamaejasme into the soil environment could be an important factor which might contribute to its competitive behavior in nature. We aimed to explore the interactions between the allelochemicals, soil enzyme activities, environmental factors and rhizosphere bacterial communities which might contribute to the plant’s invasiveness. The composition and abundance of rhizosphere soil bacteria communities were examined in five locations in the northern Tibetan Plateau. Actinobacteria and Proteobacteria were dominant in all rhizosphere soil samples and were similar among the bacterial communities. The contents of Actinobacteria showed positive correlations with neochamaejasmin B and mesoneochamaejasmin A, and negative correlations with chamaechromone and 7-methoxylneochaejasmin A. The Principle component analysis (PCA) and Redundancy analysis (RDA) revealed that Streptomycetales activity correlated with the content of neochamaejasmin B and mesoneochamaejasmin A, and Frankiales activity appeared to relate to chamaechromone and 7-methoxylneochaejasmin A. Enzyme activities and environmental factors correlated with the presence of rhizosphere soil bacterial communities. These results suggest that the allelochemicals, soil enzyme activities and the environment, to some extent, affect the composition and diversity of rhizosphere soil bacterial communities. The results provide a better understanding of the allelopathy of S. chamaejasme and its broad ecological adaptability.

摘要

Stellera chamaejasme渗出的化感化学品进入土壤环境可能是一个重要因素，可能有助于其在自然界中的竞争行为。我们旨在探讨化感化学物质，土壤酶活性，环境因素和根际细菌群落之间的相互作用，这些相互作用可能有助于植物的入侵。在青藏高原北部的五个地方检查了根际土壤细菌群落的组成和丰度。放线菌和变形杆菌在所有根际土壤样品中均占优势，并且在细菌群落中相似。放线菌的含量与新chamaejasmin B和mesoneochamaejasmin A呈正相关，与chamaechromone和7-甲氧基新奇茉莉A呈负相关。主成分分析（PCA）和冗余分析（RDA）表明，链霉菌的活性与新chaseejasmin B和mesoneochamaejasmin A的含量相关，而Frankiales的活性似乎与chamaechromone和7-甲氧基neochaejasmin A有关。酶的活性和环境因子与根际土壤细菌群落的存在。这些结果表明，化感物质，土壤酶活性和环境在一定程度上影响根际土壤细菌群落的组成和多样性。结果提供了更好的了解化感作用 酶活性和环境因素与根际土壤细菌群落的存在有关。这些结果表明，化感物质，土壤酶活性和环境在一定程度上影响根际土壤细菌群落的组成和多样性。结果提供了更好的了解化感作用 酶活性和环境因素与根际土壤细菌群落的存在有关。这些结果表明，化感物质，土壤酶活性和环境在一定程度上影响根际土壤细菌群落的组成和多样性。结果提供了更好的了解化感作用沙门氏菌及其广泛的生态适应性。