自毒物质对羟基苯甲酸降解细菌ZH2的分离与应用

自毒物质是造成植物连作障碍的主要因子,研究旨在筛选能够降解土壤中自毒物质的细菌。采用选择性分离方法从土壤中筛选自毒物质对羟基苯甲酸降解菌;结合形态特征、生理生化特征和16S rRNA测序鉴定菌种;采用紫外分光光度法测定菌株降解对羟基苯甲酸能力,并通过盆栽实验验证解毒效果。结果表明,分离到1株有降解对羟基苯甲酸能力的菌株,编号ZH2,经鉴定为绿针假单胞菌(Pseudomonas chlororaphis)。在纯培养条件下,当对羟基苯甲酸浓度为5 mg/mL时,ZH2能在培养72 h时将其降解97%。盆栽条件下,当基质中对羟基苯甲酸浓度为10 mg/g时,ZH2能有效缓解对羟基苯甲酸对黄瓜的生长抑制作用。该研究从土壤中分离到能够降解对羟基苯甲酸的绿针假单胞菌,具有应用于连作障碍防控的潜在价值。

An Autotoxicity p-Hydroxybenzoic Acid-degrading Strain ZH2: Isolation and Application

Autotoxicity is the main factor causing obstacles to continuous cropping plants. The aim of the study is to screen bacteria from soil which can degrade autotoxicity. A selective screening method was used to screen p-Hydroxybenzoic acid (PHBA) degradation bacterium. Bacterial species were identified by combining the morphological characteristics, physiological and biochemical characteristics and 16S rRNA sequencing results. The ability of the strain to degrade PHBA was determined by ultraviolet spectrophotometry. The effect of detoxification was verified by a pot experiment of cucumber. The results showed that one degradation strain (No. ZH2) was isolated and identified as Pseudomonas chlororaphis. On the condition of pure culture, ZH2 could degrade 97% at 72 h under 5 mg/mL PHBA concentration. In potted conditions, when the concentration of PHBA in the substrate was 10 mg/g, ZH2 could effectively alleviate the growth inhibition of PHBA on cucumber. We report a Pseudomonas chlororaphis strain screened from soil can degrade PHBA, it has the potential value of controlling continuous cropping obstacles.