中文摘要：

采用4种方法分别提取和纯化2种典型土壤微生物RNA（水稻土和旱地土）,并对RNA产量和质量进行比较评价.结果表明,方法1用液氮研磨法提取的RNA提取量最高,但需要纯化后才能满足RT-PCR等后续分子生物学要求;方法2用玻璃珠破碎法提取的RNA提取量稍低,但RNA纯度较高,可以直接用于RT-PCR等后续实验;方法3用试剂盒提取的RNA纯度高,但提取量最低,成本高,且对土壤样品有选择性;方法4未能提出供试土壤的微生物RNA.选择RNA提取效果较好的方法1和方法2并应用于3种典型水稻土（紫潮泥、红黄泥、麻沙泥）,结果表明,这2种方法也适合于这3种水稻土微生物RNA的提取.

英文摘要：

Four different methods were evaluated for extracting RNA from microorganisms of a paddy soil and a upland soil,the RNA quality and quantity were examined. The results showed that method 1 applying liquid nitrogen for grinding gave the highest yield but poor purity,and the additional purification was necessary for further RT-PCR. Method 2 using bead beating yielded the RNA with high purity which could be directly used for RT-PCR,but the RNA yield was lower than that of method 1. Method 3 with the commercial soil RNA extraction kit achieved high quality RNA but the lowest yield and had selectivity for soils. Method 4 is not suitable for extracting RNA from the test soils. Method 1 and method 2 with good performances on soil RNA extraction were applied to other three typical paddy soils including purple calcareous clayey soil,reddish yellow loamy soil,granitic sandy soil. The results showed that method 1 and method 2 were suitable for extracting high quality RNA from these samples,so they might be the effective methods of RNA extraction for paddy soils.