【作者】 吴艳萍；

【导师】 王国栋；

【作者基本信息】 西北农林科技大学 ， 生物物理学， 2009， 硕士

【摘要】 本研究从分子生物学角度鉴定了链霉菌菌株CM19;并从物理,化学和生物学参数方面研究了该菌株对小麦秸秆堆腐进程的影响。表明接种链霉菌对小麦秸秆堆腐过程的含水量,pH和C/N,酶活性和微生物群落变化的影响,得到以下主要结论:1.链霉菌菌株CM19的分子生物学鉴定:通过稀释涂布平板分离得到菌株,液体培养菌丝体,提取菌丝DNA,聚合酶链式反应扩增核DNA内部转录间隔区序列,进行测序,比对结果显示该菌株为Streptomyces thermovulgaris,标记为Streptomyces thermovulgaris CM19。2.链霉菌接种对小麦秸秆腐解过程温度、pH、含水量、C/N和电导率的影响:堆腐过程受到很多环境因素的影响。探讨了接种链霉菌对堆体温度pH、含水量、C/N和电导率变化的影响。结果表明,链霉菌对小麦秸秆堆腐产生显著影响。整个堆肥过程含水率呈下降趋势,接菌使得堆体含水量提高。接种链霉菌可以加速堆体温度的升高,整个过程中平均温度为44.66℃和39.55℃,接菌处理比不接菌处理高12.93%。整个堆腐过程接菌处理总的C/N为213.71,而不接菌的处理为284.03。接菌处理比不接菌处理高出33.33%。接链霉菌CM19可以提高堆体的电导率,在堆腐第15d时,接菌处理的电导率达到最大值,而且整个过程接菌处理的电导率均高于不接菌处理。可见,接链霉菌可以提高堆体中的离子浓度,从而加速堆腐进程。3.链霉菌接种对小麦秸秆堆肥进程微生物群落和酶活性的影响:进一步研究微生物菌剂在农业废弃物资源化利用中的作用及其生物学机理。采用稀释涂布平板法、BIOLOG法和分光光度法,研究了小麦秸秆堆肥体系中接种链霉菌(Streptomyces thermovulgaris)后,堆体中微生物群落结构及酶活性的动态变化。在整个堆肥过程中,接种(+M)和不接种(-M)处理的细菌和放线菌数量呈现高-低-高的趋势,真菌数量呈现一直降低的趋势。接种链霉菌菌剂,改变了堆体中细菌群落结构组成,堆体细菌总代谢活性和细菌群落多样性均增加,主成分分析显示,在整个堆肥过程,不接菌(-M)处理堆体细菌群落结构典型变量值的变异很小,而接菌(+M)的变异较大。整个堆肥过程,接菌处理(+M)的蔗糖酶活性比不接菌处理(-M)高50.07%,蛋白酶活性高21.63%。接种链霉菌(S. thermovulgaris)菌剂能够促进细菌数量的增加,可以提高堆体蔗糖酶和蛋白酶活性,但是接种处理(+M)堆体中细菌群落稳定性低于不接菌处理(-M)。更多还原

【Abstract】 This study investigated the effects of Streptomyces thermovulgaris inoculation chemical, physical, biology perimeters, such as temperature, pH, water content, EC, C/N, enzyme activity, and microbial community diversity. The strain was identified by molecular method. The mainly results are follows:1. Identification of strain CM19 by molecular method-rDNA-ITS. Medium culture method was employed to isolate fungi strain, and the strain CM19 was identified by rDNA- ITS sequence in the study. After analyzing the data got from sequence and NCBI. The strain was belonging to Streptomyces thermovulgaris, CM19.2. Effect of Streptomyces thermovulgaris inoculation on temperature, pH, water content, EC, and C/N during the wheat straw composting process. The process of composting was influenced by many environmental factors, such as temperature, pH, water content, EC, and C/N. This study investigated the effects of inoculation Streptomyces thermovulgaris on composting process of wheat straw. The results shown that inoculation Streptomyces thermovulgaris could strongly influence the composting process. Briefly, inoculation can improve water content of the wheat straw in the whole composting process, which compared with the non-inoculation treatment. The average temperatures of the two treatments were 44.66℃and 39.55℃, respectively. The C/N value of inoculation treatment was 213.71, higher than non-inoculation treatment by 33.33%. EC values reached peak value in 15 d, and the inoculation treatment was higher than non-inoculation. Therefore, inoculation can improve composting process.3. Effects of Streptomyces thermovulgaris on microbial community and enzyme activity during wheat straw composting process. In order to assess the role and biology mechanism of microbial in agricultural waste utilization, microbial cultural, BIOLOG and spectrophotometry method were employed to investigate the effects of Streptomyces thermovulgaris on microbial community and enzyme activity during wheat straw composting process. The trends of the number of bacteria and antionmies were high-low-high, and the number of fungi decreases during the composting process. Bacteria community structure was changed after incubating S. thermovulgaris agent. AWCD and bacteria community diversity were increased, respectively. Principal component analyses indicated that the variation of inoculation treatment (+M) were larger than non-inoculation treatment (-M) thought out the composting process. Sucrose enzyme activity and protein enzyme activity of inoculation treatment (+M) were higher than non-inoculation treatment (-M) for 50.07% and 21.63%, respectively. The number of bacteria, sucrose enzyme activity and protein enzyme activity were improved after inoculating S.thermovulgaris agent, however, the stability of bacteria community in inoculation treatment (+M) was lower than that of non-inoculation treatment(-M).更多还原