Plant growth-promoting potential of endophytic bacteria isolated from roots of coastal sand dune plants.
Endophytic bacteria associated with the roots of coastal sand dune plants were isolated, taxonomically characterized, and tested for their plant growth-promoting activities. Ninety-one endophytic bacterial isolates were collected and assigned to 17 different genera of 6 major bacterial phyla based on partial 16S rDNA sequence analyses. Gammaproteobacteria represented the majority of the isolates (65.9%), and members of Pseudomonas constituted 49.5% of the total isolates. When testing for antagonism towards plant pathogenic fungi, 25 strains were antagonistic towards Rhizoctonia solani, 57 strains were antagonistic towards Pythium ultimum, 53 strains were antagonistic towards Fusarium oxysporum, and 41 strains were antagonistic towards Botrytis cinerea. Seven strains were shown to produce indole acetic acid (IAA), 33 to produce siderophores, 23 to produce protease, 37 to produce pectinase, and 38 to produce chitinase. The broadest spectra of activities were observed among the Pseudomonas strains, indicating outstanding plant growth-promoting potential. The isolates from C. kobomugi and M. sibirica also exhibited good plant growth-promoting potential. The correlations among individual plant growth-promoting activities were examined using phi coefficients, and the resulting data indicated that the production of protease, pectinase, chitinase, and siderophores was highly related.
Department of Microbiology, Chungnam National University, Daejeon 305-764, Korea.
Dong-Sung
DS
Shin
Myung Soo
MS
Park
Sera
S
Jung
Myoung Sook
MS
Lee
Kang Hyun
KH
Lee
Kyung Sook
KS
Bae
Seung Bum
SB
Kim
D000898:Antibiosis; D001419:Bacteria / Q000145:classification* / Q000302:isolation & purification*; D018407:Bacterial Physiological Phenomena; D002688:Chitinases / Q000096:biosynthesis; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D005658:Fungi / Q000254:growth & development; D007210:Indoleacetic Acids / Q000378:metabolism; D010447:Peptide Hydrolases / Q000096:biosynthesis; D010802:Phylogeny; D018517:Plant Roots / Q000382:microbiology*; D010944:Plants / Q000382:microbiology*; D011096:Polygalacturonase / Q000096:biosynthesis; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D012689:Sequence Homology, Nucleic Acid; D017262:Siderophores / Q000096:biosynthesis
D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D007210:Indoleacetic Acids; D012336:RNA, Ribosomal, 16S; D017262:Siderophores; C030737:indoleacetic acid; D002688:Chitinases; D011096:Polygalacturonase; D010447:Peptide Hydrolases