Characterization of plant-growth promoting diazotrophic bacteria isolated from field grown Chinese cabbage under different fertilization conditions.
Diazotrophic bacteria isolated from the rhizosphere of Chinese cabbage were assessed for other plant growth promoting characteristics viz., production of IAA, ethylene, ACC deaminase, phosphate solubilization, and gnotobiotic root elongation. Their effect on inoculation to Chinese cabbage was also observed under growth chamber conditions. A total of 19 strains that showed higher nitrogenase activity identified by 16S rRNA gene sequence analysis were found to be the members of the genera Pseudomonas and Agrobacterium belonging to alpha- and gamma-Proteobacteria groups. These strains were also efficient in producing IAA and ACC deaminase though they produced low levels of ethylene and no phosphate solubilization. In addition, inoculation of selected diazotrophic bacterial strains significantly increased seedling length, dry weight, and total nitrogen when compared to uninoculated control. The colonization of crop plants by diazotrophic bacteria can be affected by many biotic and abiotic factors, and further studies are oriented towards investigating the factors that could influence the establishment of a selected bacterial community.
Department of Agricultural Chemistry, Chungbuk National University, Cheongju, Chungbuk, 361-763, Republic of Korea.
Woo-Jong
WJ
Yim
Selvaraj
S
Poonguzhali
Munusamy
M
Madhaiyan
Pitchai
P
Palaniappan
M A
MA
Siddikee
Tongmin
T
Sa
D001419:Bacteria / Q000201:enzymology / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism*; D001426:Bacterial Proteins / Q000378:metabolism; D001937:Brassica / Q000254:growth & development / Q000382:microbiology*; D005030:Ethylenes / Q000378:metabolism; D005308:Fertilizers / Q000032:analysis; D007210:Indoleacetic Acids / Q000378:metabolism; D008969:Molecular Sequence Data; D009586:Nitrogen Fixation; D010802:Phylogeny; D010937:Plant Growth Regulators / Q000378:metabolism*; D018517:Plant Roots / Q000254:growth & development / Q000382:microbiology; D012988:Soil Microbiology
D001426:Bacterial Proteins; D005030:Ethylenes; D005308:Fertilizers; D007210:Indoleacetic Acids; D010937:Plant Growth Regulators; C030737:indoleacetic acid; C036216:ethylene