以大豆根际土壤样品为研究材料,采用一个气体循环培养体系(持续通氢气装置),在适当的H2、O2和CO2下以H2作为唯一能源分离氢氧化细菌,结果共分离出40余株细菌,对其进行耗氢能力测定,结果显示有20株菌具有氧化氢功能和自养生长能力。对20株氢氧化细菌进行小麦促生试验,筛选出11株具有促生效果的根际促生细菌。采用薄层层析法,对11株氢氧化细菌进行了ACC降解的分析,确定了菌株氏。具有ACC脱氨酶活性,证实ACC脱氨酶是导致大豆根际土壤中氢氧化细菌促进小麦幼苗生长的原因之一。
Mineral salt agar medium (MSA) was used to separate hydrogen-oxidizing bacteria in soybean rhizosphere which were able to utilize hydrogen as sole energy. A gas-cycle incubation system (H2 treatment system) was developed that provided stable H2 exposure rate (4.16 × 10^-5-l. 25 × 10^-4 mol · L^-1) by electrolysis. 40 bacterium strains were isolated by the incubation system,and the capability of uptaking hydrogen of these strains were measured. The results showed that 20 bacterium strains had the ability to uptake hydrogen and grow chemolithoautotrophically. The growth-promoting capability of 20 strains was tested. 11 bacteria strains were proved that they could markedly promote root growth of wheat in different extent. The ability of 11 bacteria strains on using ACC as nitrogen resources were examined through thin layer chromatography analysis. The results showed that the A06 strain could utilize ACC as nitrogen resource, suggested that A06 has ACC deaminase. ACC deaminase is the main reason to promote the growth of wheat according to hydrogen-oxidizing bacteria in soybean rhizosphere.