本文選題：鄂爾多斯 + 烏海　； 參考：《內(nèi)蒙古農(nóng)業(yè)大學(xué)》2017年碩士論文

【摘要】：粘細(xì)菌(Myxobacteria)是一類比較特殊的革蘭氏陰性真細(xì)菌,可以滑行運(yùn)動(dòng),并且具有復(fù)雜多變的形態(tài)發(fā)生和種類多樣的多細(xì)胞行為,能夠通過營(yíng)養(yǎng)細(xì)胞之間生物信號(hào)的相互感應(yīng)與傳遞進(jìn)行滑動(dòng)、群體攝食以及形成特有的子實(shí)體和抗逆粘孢子,具有明顯的社會(huì)性行為。由于粘細(xì)菌可產(chǎn)生豐富且結(jié)構(gòu)新穎、種類多樣、作用機(jī)制獨(dú)特的次級(jí)代謝產(chǎn)物,所以其在抗病原真菌、細(xì)菌、抗病毒、抗腫瘤方面具有巨大的潛在應(yīng)用價(jià)值,是一類有著極大的研究和實(shí)際開發(fā)價(jià)值的微生物類群。本論文的主要目的是開發(fā)新的粘細(xì)菌資源,從而獲得抗馬鈴薯晚疫病活性較高的菌株和次級(jí)代謝產(chǎn)物。本研究按照土壤類型的不同設(shè)計(jì)采樣計(jì)劃,以采集自我國(guó)內(nèi)蒙古自治區(qū)西部鄂爾多斯和烏海地區(qū)的46份土壤樣品為研究對(duì)象,進(jìn)行土壤微生物計(jì)數(shù)、土壤理化性質(zhì)測(cè)定以及土壤粘細(xì)菌的分離純化與鑒定,并對(duì)純化菌株進(jìn)行抗致病疫霉活性分析,對(duì)活性較高的菌株進(jìn)行了發(fā)酵條件的優(yōu)化。內(nèi)蒙古西部鄂爾多斯和烏海地區(qū)微生物數(shù)量偏低,土壤pH呈中性偏堿性,絕大部分土壤存在旱情,土壤肥料含量也普遍較低。從46份土壤樣品中富集分離出粘細(xì)菌191株,純化出102株,分屬5個(gè)屬,11個(gè)種,其分別為:橙色粘球菌、黃色粘球菌、變綠粘球菌、葉柄粘球菌、珊瑚裝珊瑚球菌、大孢珊瑚球菌、弱小珊瑚球菌、Pyxicoccus fallax、Cytobacter Violaceus、深褐孢囊桿菌、過度原囊菌。粘細(xì)菌的分布呈:林地草地耕地荒地。溶細(xì)菌類群、溶纖維素類群及粘細(xì)菌總數(shù)與土壤速效鉀和有機(jī)質(zhì)表現(xiàn)出顯著的相關(guān)性,與有機(jī)質(zhì)的相關(guān)系數(shù)分別達(dá)到0.690、0.543和0.732。72%的供試菌株對(duì)致病疫霉的生長(zhǎng)產(chǎn)生不同程度的拮抗作用。拮抗效果最佳的為菌株E10、E11和E12,其抑菌直徑分別達(dá)到:26、24、24 mm。菌株E10 為弱小珊瑚球菌(Corallococcws exigwows),菌株 E11 為匣狀粘球菌(Pyxidicoccus fallax),菌株E12為珊瑚狀珊瑚球菌(Corallococcus coralloiides)。菌株E10的最適發(fā)酵培養(yǎng)基為MX04(MD1),最適發(fā)酵條件為溫度32 ℃,時(shí)間11 d,鹽度0%;菌株E11的最適發(fā)酵培養(yǎng)基為MX01(VY/2),最適發(fā)酵條件為溫度36℃,時(shí)間11 d,鹽度0.5%;菌株E12的最適發(fā)酵培養(yǎng)基為MX04(MD1),最適發(fā)酵條件為溫度32 ℃,時(shí)間111d,鹽度0%;3株菌發(fā)酵液中拮抗致病疫霉生物活性物質(zhì)均易溶于有機(jī)物,而難溶于水,大孔樹脂可以在粘細(xì)菌的發(fā)酵過程中很好的吸附其產(chǎn)生的次級(jí)代謝產(chǎn)物。該工作的完成為抗馬鈴薯晚疫病生物農(nóng)藥的開發(fā)提供基礎(chǔ)數(shù)據(jù)。
[Abstract]:Myxobacteria (Myxobacteria) is a special class of Gram-negative true bacteria that can glide and have complex morphogenesis and diverse multicellular behavior. It can glide through the mutual induction and transmission of biological signals between vegetative cells, feed on the population, and form special fruiting bodies and endospores, which has obvious social behavior. Because myxobacteria can produce abundant secondary metabolites with novel structure, various species and unique mechanism of action, they have great potential application value in resistant fungi, bacteria, anti-virus and anti-tumor. It is a kind of microorganism that has great research and practical development value. The main purpose of this paper is to develop new myxobacterium resources and to obtain high activity strains and secondary metabolites of potato late blight resistance. In this study, 46 soil samples from Ordos and Wuhai areas of Inner Mongolia Autonomous region were collected according to different soil type sampling plans, and soil microbial count was carried out. The physicochemical properties of soil and the isolation, purification and identification of soil myxobacteria were determined, and the anti-Phytophthora activity of the purified strains was analyzed. The fermentation conditions of the strains with higher activity were optimized. The amount of microbes in Ordos and Wuhai areas in western Inner Mongolia is low, the soil pH is neutral and alkaline, most of the soil exists drought, and the soil fertilizer content is generally low. 191 strains of myxobacteria were isolated from 46 soil samples, and 102 strains, belonging to 5 genera and 11 species, were isolated. Pyxicoccus fallaxa Cytobacter Violaceus, Bacillus fulminatum, Protosporium. The distribution of myxobacteria is as follows: woodland, grassland, cultivated land, wasteland. The number of soluble bacteria, cellulose and myxobacteria were significantly correlated with soil available potassium and organic matter. The correlation coefficient with organic matter reached 0.690%, 0.543% and 0.732.72%, respectively, which had different antagonistic effects on the growth of Phytophthora infestans. The antagonistic effects of E10 E11 and E12 were the best, and the inhibitory diameters of E10 E11 and E12 reached to 24 mm and 24 mm, respectively. Strain E10 was Corallococcws exigwowsm, strain E11 was Pyxidicoccus fallaxa and strain E12 was Corallococcus coralloiideschus. The optimum fermentation medium for strain E10 was MX04MMD1, and the optimum fermentation conditions were temperature 32 鈩，

本文編號(hào)：1976156