环境微生物对大豆根瘤菌USDA110结瘤的影响
毕业论文关键词：大豆根瘤；内生细菌；16S rDNA；促生；匹配结瘤
The Effect to the USDA110 of Endogenous Bacteria from Root Nodule
Abstract：During the synaptic formation of nitrogen-fixing symbiont between legumes and rhizobia，the typical featureis the formation of root nodules and/or stem nodules induced by specific microsymbiont. Except for rhizobia，inside the root nodules there are various endogenous bacteria that have relation to rhizobial symbiotic, nitrogen fixation been isolated and the general coexistence of rhizobia with the bacteria in the same root nodule is ubiquitously objective phenomena. And existed in the root nodules were not able to induce the plants into morbidity. However very little of their ecological role have been aware of. This research took the 219 types of soybean nodules as samples，the control group was set up, and the experimental group was inoculated with the rhizobia USDA110, the DNA of the two samples was extracted and the bacterial community was analyzed .Then isolating endophytes by plate streaking. 16S rDNA sequence analysis were applied to explore the bacterias which have plant growth promoting characteristics.
Key words: soybean nodule；endophytic bacteria；16S rDNA；plant growth promotion；matching of nodulation
目 录
摘要 3
关键词 3
Abstract 3
Key words 3
引言 3
一 大豆根瘤内生细菌的分离及对USDA110结瘤的影响 5
1 材料与方法 5
1．1 供试材料 5
1．1．1 菌株 5
1．1．2 培养基及培养条件 5
1．1．3 大豆品种 6
1．2 实验方法 10
1．2．1 种子催芽 10
1．2．2 土壤中结瘤实验 10
1．2．3 DNA 的提取 11
1．2．4 挑选出16菌的16S DNA PCR扩增 11
1．1．5 内生细菌与USDA110的联合接种 11
2 结果与分析 11
2．1 总16S rDNA分析 11
2. 1. 1细菌群落结构在目水平上旳变化 11
2. 1. 2 细菌群落结构在属水平上的变化 13
2. 2 对分离的16个菌株的分析 14
2. 3 根瘤内生细菌对USDA110结瘤的影响 14
3 讨论 15
二 USDA110与大豆品种匹配性的研究 16
1 材料与方法 16
1．1 供试材料 16
1．1．1 菌株 16
1．1．2 培养基及培养条件 16
1．1．3 大豆品种 16
1．2 实验方法 16
1．2．1 种子催芽 16
1．2．2 花盆消毒 16