本文關(guān)鍵詞：二甲戊靈降解菌的篩選及降解效果評(píng)價(jià)　出處：《石河子大學(xué)》2017年碩士論文　論文類型：學(xué)位論文

  更多相關(guān)文章： 二甲戊靈 降解菌 沙雷氏菌 假單胞菌 培養(yǎng)基 土壤

【摘要】：二甲戊靈是二硝基苯胺類選擇性土壤處理除草劑,在新疆普遍應(yīng)用于棉田進(jìn)行土壤處理,二甲戊靈的大量施用嚴(yán)重毀壞了土壤中的微生物系統(tǒng),影響土壤質(zhì)量。本研究利用土壤中多樣的微生物類群、采用富集培養(yǎng)的方法,定向篩選新疆棉田土壤中二甲戊靈的高效降解細(xì)菌,研究其降解特征,探索其降解條件和降解效率,為新疆棉田二甲戊靈污染土壤的治理與修復(fù)提供理論基礎(chǔ)和技術(shù)支持。1.采用富集培養(yǎng)法從新疆的棉田土壤中篩選二甲戊靈高效降解菌株,經(jīng)平板法初篩獲得9株高度耐受且具備降解能力的細(xì)菌菌株,采用氣相色譜法對(duì)其降解能力進(jìn)行檢測(cè),確定了2株高效降解菌,命名為JY-2和JY-5,3 d內(nèi)對(duì)200 mg/L二甲戊靈的降解效率在70%以上,9 d內(nèi)對(duì)500 mg/L二甲戊靈的降解效率達(dá)90%以上;2.通過(guò)常規(guī)形態(tài)學(xué)鑒定和16S rDNA序列分析對(duì)其鑒定,鑒定的結(jié)果為:菌株JY-2為沙雷氏菌(Serratia sp.),菌株JY-5為假單胞菌(Pseudomonas sp.);3.在培養(yǎng)基環(huán)境中,研究了降解菌株的降解條件。該2株細(xì)菌能夠在二甲戊靈作為唯一碳源的無(wú)機(jī)鹽培養(yǎng)基中生長(zhǎng),在蔗糖濃度0.5%、接種量體積10%、初始二甲戊靈濃度200 mg/L、pH 7.0、溫度30℃培養(yǎng)環(huán)境中振蕩培養(yǎng)3 d,二甲戊靈的降解率分別可達(dá)83.34%和82.79%;4.以細(xì)菌JY-2和JY-5為供試菌株,實(shí)驗(yàn)室條件下,研究其對(duì)二甲戊靈污染土壤的修復(fù)作用及其影響因素,結(jié)果表明,二甲戊靈的降解率與接種量呈正相關(guān),其中,細(xì)菌JY-2或JY-5的接種量為10%(0.6×109 cfu·g-1土)時(shí),對(duì)土壤中200 mg/kg二甲戊靈15 d后降解率可達(dá)66.18%和65.66%,低于此濃度,降解菌的降解作用較弱;此外,土壤溫度及含水量對(duì)菌株降解也產(chǎn)生了顯著的影響,研究表明,土壤中適宜的降解溫度為30℃,含水量為600 g/kg;5.采用生物法對(duì)菌株的降解效率進(jìn)行驗(yàn)證,藥劑處理組玉米和棉花出苗率為33.33%和71.11%,投入二甲戊靈降解菌后,土壤中二甲戊靈濃度降低,玉米出苗率提高到55.56%和67.78%,棉花出苗率增加到88.89%和91.11%,均差異顯著。接種細(xì)菌JY-2和JY-5可不同程度減輕土壤中二甲戊靈對(duì)玉米和棉花的生長(zhǎng)抑制作用,具有一定的土壤修復(fù)能力。
[Abstract]:Penicillin is a selective herbicide for soil treatment of dinitroaniline, which is widely used in cotton fields in Xinjiang for soil treatment. The extensive application of penicillin has seriously destroyed the microbial system in soil. In this study, we used a variety of soil microbial groups, using enrichment culture method, targeted screening of high-efficient degradation bacteria in Xinjiang cotton field soil, and studied its degradation characteristics. To explore the degradation conditions and degradation efficiency. To provide theoretical and technical support for the treatment and remediation of the contaminated soil in Xinjiang cotton field. 1. Screening the high-efficient degrading strains of penicillin from cotton soil in Xinjiang by enrichment culture method. Nine strains of bacteria with high tolerance and biodegradability were obtained by plate method. The biodegradability of 9 strains was detected by gas chromatography, and two strains of highly efficient biodegradable bacteria were identified, named JY-2 and JY-5. In 3 days, the degradation efficiency of 200 mg/L dimethylpentalin was more than 70% and the degradation efficiency of 500 mg/L dimethyl pentyl reached more than 90% in 9 days. 2. The results of routine morphological identification and 16s rDNA sequence analysis showed that the strain JY-2 was Serratia Shareh sp.). The strain JY-5 was Pseudomonas sp. 3. The degradation conditions of the degrading strains were studied in the medium environment. The two strains were able to grow in the inorganic salt medium with dimethylpentalin as the sole carbon source and the sucrose concentration was 0.5%. The inoculation volume was 10: 10, the initial concentration of dimethylpentalin was 200 mg / L ~ (-1) pH 7.0, the temperature was 30 鈩，

本文編號(hào)：1423260