pgpr促进作用研究论文翻译

Screening and Identification of strain with ACC deaminase activityAbstract:Many experiments show that, rhizosphere PGPR (plant growth-promoting rhizobacteria) with ACC (1 - aminocyclopropance-1-carboxylic) deaminase activity helps promote plant growth by enhancing resistance against drought, salt, heavy metals and other environmetal stresses. This experiment proposed to screen high - yielding ACC deaminase activity of strains from the rhizosphere of different plants in Nature Reserve of Red-Crown Crane in Sheyang, Jiangsu in order to excavate possible rare microbial resources, on the other hand, provide strains material for the development of microbial agents. Therefore, this study is to formulate the preparation of ACC as the only nitrogen source selection medium, by comparing the growth rate of each strain. 20 representative strains (from 20 operational taxonomic units), with different rhizosphere from Nature Reserve of Red-Crown Crane in Sheyang, Jiangsu were screened. 4 were picked (strain #5, #8, #15 and #17) for rescreening; ACC deaminase activity of each strain was being measured, the strongest strains were tested with a 16S rRNA genome sequencing identification test on the enzyme activities. The results showed that, among the 4 strains which were picked for screening, strain #15 produced the highest ACC deaminase activity, reaching 4.97 μmol / (mg · h), which was significantly higher than strain #5, #8 and #17 (p <0.05), 3.64 μmol / (mg · h), 3.80 μmol / (mg · h) and 2.11 μmol / (mg · h) respectively. A molecular identification was carried out on strain #15, its 16S rRNA genome sequences is 99% similar to a Klebsiella pneumonial, which indicates that the strain is a Klebsiella sp. This study is to provide strain materials for the development of highly effective microbial fertilizer [Keywords] ACC deaminase activity, screening, enzyme assays, identification,The main instruments and equipments,Reagents and method of preparation,Screening of ACC deaminase activity,The standard curve of α-keto acid,ACC deaminase activity of four strains,16S rRNA gene sequence phylogenetic tree of strain #15