太子参为石竹科多年生草本植物,以根部入药,药用价值高,市场需求大,但其栽培过程中存在严重的连作障碍问题,连作导致产量品质严重下降,病虫害猖獗,探索太子参连作障碍形成的机制及其消减措施意义重大.本研究以广泛栽培的“柘参2号”为试验材料,采用土壤农化分析、高效液相色谱(HPLC)分析、荧光定量PCR(qPCR)等技术对不同连作年限或不同消减措施下太子参根际土壤的主要养分、酚酸含量动态及特异菌群变化进行分析.结果显示:太子参连作导致产量显著下降,与正茬相比产量下降达43.5%,而水旱轮作和微生物菌肥处理可不同程度缓解其障碍效应.太子参连作土壤主要养分(如速效氮、速效磷、速效钾、全钾)未降反升,但导致土壤酸化.HPLC分析表明,太子参连作下或者随生长时期的推进,土壤酚酸类物质并未表现出明显的积累效应,膨大中期和收获期重茬土壤中大部分酚酸含量甚至低于正茬土壤.进一步荧光定量PCR分析发现,太子参连作导致前期分离筛选到的几类病原菌(如尖孢镰刀菌、踝节霉菌、Kosakonia sacchari)的绝对含量显著上升,而水旱轮作和微生物菌肥处理可有效降低3类病原菌的含量,改善微生态结构.综上认为,太子参连作障碍的发生并非由土壤养分匮乏或者酚酸持续积累直接造成,可能主要与连作下土传病原微生物的大量繁殖爆发有关,本研究结果为深入揭示太子参连作障碍的形成机制及消减修复机制提供了理论依据. Pseudostellaria heterophylla is a perennial herb of Caryophyllaceae, root medicine, high medicinal value, market demand, but there is a serious problem of continuous cropping obstacle in the process of cultivation. Continuous cropping lead to a serious decline in yield and quality, rampant pests and diseases, to explore the formation of heterophylla heterophylla And its abatement measures are of great significance.In this study, widely cultivated “Shen 2” as test material, using soil agronomic analysis, high performance liquid chromatography (HPLC) analysis, quantitative PCR (qPCR) and other techniques The results showed that the production of Pseudostellaria heterophylla reduced significantly, and the yield decreased by 43.5% compared with that of the continuous cropping. %, While the rotation and micro-organism fertilizer treatment could alleviate the obstacle effect to some extent.Pseudospavounensis did not rise but increased the main nutrients of soil (such as available nitrogen, available phosphorus, available potassium and total potassium), but caused soil acidification.HPLC The analysis showed that the soil phenolic acids did not show obvious accumulation effect under the continuous or prolonged growth of Pseudostellaria heterophylla, Some phenolic acids were even lower than that of positive soil.Further quantitative PCR analysis showed that the absolute content of several pathogenic bacteria (such as Fusarium oxysporum, Kosakonia sacchari) that were isolated and screened by Pseudostellaria heterophylla was significantly increased, However, the rotation and microbial fertilization could effectively reduce the content of three kinds of pathogenic bacteria and improve the micro-ecological structure.In summary, the occurrence of continuous heterosis in P. heterophylla was not directly caused by the lack of soil nutrients or the continuous accumulation of phenolic acids, The results of this study provide a theoretical basis for further revealing the formation mechanism of Coptis chinensis continuous cropping obstacle and the mechanism of abatement and repair.