College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, Fujian, P. R. China.
Key Laboratory of Biopesticide and Chemical Biology, Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou 350002, Fujian, P. R. China.
Sci Rep. 2016 May 24;6:26601. doi: 10.1038/srep26601.
Under consecutive monoculture, the biomass and quality of Pseudostellaria heterophylla declines significantly. In this study, a three-year field experiment was conducted to identify typical growth inhibition effects caused by extended monoculturing of P. heterophylla. Deep pyrosequencing was used to examine changes in the structure and composition of soil fungal community along a three-year gradient of monoculture. The results revealed a distinct separation between the newly planted plot and the two-year, three-year monocultured plots. The Shannon and Simpson diversity indices were significantly higher in the two-year and three-year monoculture soils than in the newly planted soil. Consecutive monoculture of this plant led to a significant increase in relative abundance of Fusarium, Trichocladium and Myrothecium and Simplicillium, etc., but a significant decrease in the relative abundance of Penicillium. Quantitative PCR analysis confirmed a significant increase in Fusarium oxysporum, an agent known to cause wilt and rot disease of P. heterophylla. Furthermore, phenolic acid mixture at a ratio similar to that found in the rhizosphere could promote mycelial growth of pathogenic F. oxysporum. Overall, this study demonstrated that consecutive monoculture of P. heterophylla can alter the fungal community in the rhizosphere, including enrichment of host-specific pathogenic fungi at the expense of plant-beneficial fungi.
在连续的单一种植下，三叶半夏的生物量和质量显著下降。本研究通过三年田间试验，鉴定了三叶半夏长期单一种植引起的典型生长抑制效应。通过深度焦磷酸测序，研究了在三叶半夏连续单一种植三年的梯度上，土壤真菌群落结构和组成的变化。结果表明，新种植区与两年和三年单种区明显分离。两年和三年单种土壤的 Shannon 和 Simpson 多样性指数显著高于新种植土壤。连续单一种植这种植物会导致镰孢菌、 Trichocladium 和 Myrothecium 等的相对丰度显著增加，而青霉菌的相对丰度显著降低。定量 PCR 分析证实，引起三叶半夏萎蔫和腐烂病的病原菌尖孢镰刀菌的丰度显著增加。此外，与根际中发现的比例相似的酚酸混合物可以促进致病尖孢镰刀菌的菌丝生长。总的来说，本研究表明，三叶半夏的连续单一种植会改变根际中的真菌群落，包括以牺牲植物有益真菌为代价，富集宿主特异性的致病真菌。
