水稻根际促生菌的筛选鉴定及促生能力分析

摘要

Plant growth- promoting rhizobacteria(PGPR)can secrete the growth hormone and promote soil nutrient cycling, thus, is an important germplasm resource of bio-fertilizer. In this study, the PGPR was isolated from the rice rhizosphere. According to 16S rDNA sequences, 10 strains were identifed, including 4 organic phosphorus bacteria(Bacillus pumilus LZP02, Bacillus aryabhattai LZP08, Staphylococcus epidermidis LZP10, Bacillus ginsengisoli LZP05), 3 inorganic phosphorus bacteria(Bacillus megaterium LZP03, Bacillus oryzaecorticis LZP04,Bacillus ginsengisoli LZP07)and 3 potassium bacteria(Bacillus aryabhattai LZP01,Bacillus subtilis LZP06,Bacillus licheniformis LZP09). The results from nutrient conversion analysis showed that Bacillus aryabhattai LZP01 and Bacillus subtilis LZP06 performed better on the potassium releasing ability. Bacillus pumilus LZP02 and Bacillus huizhouensis LZP05 performed better on the function of organic phosphorus. Bacillus megaterium LZP03 and Bacillus ginsengisoli LZP07 performed better on the function of inorganic phosphorus.Further,the hormone secretion capacity was measured for these 6 strains.The results showed that all 6 strains could produce auxin and gibberellin,and had the ability to synthesize iron carrier.Moreover,the results showed that Bacillus megaterium LZP03,Bacillus huizhouensis LZP05 and Bacillus subtilis LZP06 had stronger ability to promote the nutrient conversion and hormone secretion. Systematically,we believe that these three strains have great potential application on microbial fertilizer.%植物根际促生菌(Plant growth-promoting rhizobacteria,PGPR)可分泌植物生长激素,促进土壤养分循环,是生物肥料重要的种质资源.本文从水稻根际土壤分离纯化根际促生菌,进行菌株鉴定,测定其促生能力.经过16S rDNA测序比对,筛选得到解磷菌4株(Bacillus pumilus LZP02,Bacillus aryabhattai LZP08,Staphylococcus epidermidis LZP10,Bacillus ginsengisoli LZP05),溶磷菌3株(Bacillus megaterium LZP03,Bacillus oryzaecorticis LZP04,Bacillus ginsengisoli LZP07),解钾菌3株(Bacillus aryabhattai LZP01, Bacillus subtilis LZP06,Bacillus licheniformis LZP09).养分转化能力测试结果表明,Bacillus aryabhattai LZP01和 Bacillus subtilis LZP06解钾能力较好;Bacillus pumilus LZP02和Bacillus huizhouensis LZP05解磷能力较强;Bacillus megaterium LZP03和Bacillus ginsengisoli LZP07溶磷能力较好.对养分转化能力较强的菌株进行激素分泌能力测定,结果表明6种菌株均能产生生长素、赤霉素,均具有合成铁载体的能力.综合分析菌株养分转化与激素分泌能力发现,Bacillus megaterium LZP03、Bacillus huizhouensis LZP05和Bacillus subtilis LZP06促生能力较强,具有较强的开发利用潜力.研究成果为水稻微生物肥料的开发与生产提供了理论和技术支持.