连作苦瓜根际土壤酚酸物质与微生物群落结构的互作机制

Continuous cropping obstacle is the bottleneck problem of agricultural sustainable development. The reasons, such as the special climate environment, the shortage of cultivated land resource, the imperfect of cultivation management system, the restriction factors of production environment of Hainan Province, and so on, lead to very serious and increasing problem of the continuous cropping obstacles of bitter gourd. Interaction between phenolic acids and microbial community of rhizosphere soil may be the important reason leading to the continuous cropping obstacle of bitter gourd. Therefore, the rhizosphere soil of continuously cropped bitter gourd will be chose as the research object in this study. The accumulation change of phenolic acids will be analyzed by LC-MS, and the dynamic change of microbial community structure will be analyzed by high throughput sequencing and bioinformatics. Then the interaction between phenolic acids and microbial community structure will be evaluated comprehensively. With the exogenous chemical reference substance of identified phenolic acids and pot experiment, the interaction effects between different concentrations of phenolic acids and soil microbial community structure will be further studied, in order to clarify the mechanism of interaction between phenolic acids and soil microbial community structure. This research will provide theory basis and technical assistance for studying the effective measures of abatement continuous cropping obstacle of bitter gourd, and lay a foundation for remediation the micro-ecology environment of continuous cropped soil.

连作障碍是制约农业可持续发展的瓶颈问题。海南特有的气候环境和短缺的耕地资源以及栽培管理制度的不健全和生产环境的制约等因素使得苦瓜连作障碍十分严重且日益加剧。根际土壤酚酸类物质与微生物群落结构的相互作用可能是导致苦瓜连作障碍的重要原因。因此，本项目以连作苦瓜根际土壤为研究对象，采用液质联用（LC-MS）方法鉴定分析酚酸类物质的累积变化，采用高通量测序和生物信息学相结合的方法分析微生物群落结构的动态变化，综合评价根际土壤酚酸类物质与微生物群落结构的互作关系；选用已鉴定的酚酸类物质的外源化学标准品，采用盆栽试验进一步研究不同浓度的各酚酸类物质与土壤微生物群落结构的互作效应，阐明酚酸类物质与土壤微生物群落结构间的互作机制，为消减苦瓜连作障碍有效措施的研究提供理论依据和技术支持，为修复连作土壤微生态环境奠定基础。

连作障碍是制约农业可持续发展的瓶颈问题。海南特有的气候环境和短缺的耕地资源以及栽培管理制度的不健全和生产环境的制约等因素使得苦瓜连作障碍十分严重且日益加剧。根际土壤酚酸类物质与微生物群落结构的相互作用可能是导致苦瓜连作障碍的重要原因。因此，本项目以连作苦瓜根际土壤为研究对象，采用液质联用（LC-MS）方法鉴定分析酚酸类物质的累积变化，采用高通量测序和生物信息学相结合的方法分析微生物群落结构的动态变化，综合评价根际土壤酚酸类物质与微生物群落结构的互作关系；选用已鉴定的酚酸类物质的外源化学标准品，采用盆栽试验进一步研究不同浓度的各酚酸类物质与土壤微生物群落结构的互作效应，阐明酚酸类物质与土壤微生物群落结构间的互作机制。主要研究结果如下：.1. 根际土壤总酚酸、对羟基苯甲酸和香草酸的含量随着连作茬次的增加显著降低；阿魏酸、苯甲酸和苯丙酸含量呈先升高后降低的变化趋势；水杨酸含量在连作第四茬的时候显著增加；肉桂酸含量在各连作茬次午显著性差异。.2. 连作苦瓜根际土壤多样性和丰富度显著下降，物种组成和群落结构存在显著差异，且趋于单一化。.3. 全面系统的分析了连作苦瓜根际土壤中的酚酸物质（总酚酸、阿魏酸、香草酸、水杨酸、对羟基苯甲酸、苯甲酸、苯丙酸和肉桂酸）与土壤微生物真菌和细菌群落结构及多样性的相关性，明确了二者的显著相关性和互作效应。.4. 通过系列浓度梯度水杨酸处理试验发现，不同浓度的水杨酸对土壤微生物群落结构及物种组成有显著差异，高浓度的水杨酸可降低土壤微生物群落的丰富度和多样性。水杨酸可能通过调控土壤的微生物群落物种组成和多样性，导致蔬菜作物连作障碍现象的发生。.本项目的研究结果可以为消减苦瓜连作障碍有效措施的研究提供理论依据和技术支持，为修复连作土壤微生态环境奠定基础。