Isolation and characterization of antagonistic bacteria against bacterial leaf spot of Euphorbia pulcherrima.
OBJECTIVE
To investigate the inhibition potential of leaf-associated bacteria against the pathogen of bacterial leaf spot of Euphorbia pulcherrima.


RESULTS
Seven out of 200 bacterial strains were effective antagonists by in vitro screening and the two strains PAB241 and PAB242 significantly reduced the disease incidence and severity as foliar treatments of E. pulcherrima. The two effective strains, PAB241 and PAB242, were both identified as Bacillus amyloliquefaciens by a polyphasic approach including phenotypic feature, carbon source utilization profile, fatty acid methyl esters and analysis of 16S rRNA gene sequence. In addition, the suspensions of B. amyloliquefaciens PAB241 and PAB242 showed antibacterial activities against the pathogen of bacterial leaf spot of E. pulcherrima under different treatments.


CONCLUSIONS
The leaf-associated bacteria, B. amyloliquefaciens PAB241 and PAB242, markedly inhibited the growth of X. axonopodis pv. poinsettiicola under different treatments and protected E. pulcherrima from pathogen infection in growth chamber conditions.


CONCLUSIONS
This is the first study that showed B. amyloliquefaciens from plant leaves was a potential bactericide against bacterial leaf spot of E. pulcherrima.
Li
B
B
Institute of Biotechnology, Zhejiang University, Hangzhou, China. libin0571@hotmail.com
Xu
L H
LH
Lou
M M
MM
Li
F
F
Zhang
Y D
YD
Xie
G L
GL
D000898:Antibiosis; D001407:Bacillus / Q000145:classification / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism*; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D028481:Euphorbia / Q000382:microbiology*; D010802:Phylogeny; D010935:Plant Diseases / Q000382:microbiology*; D018515:Plant Leaves / Q000382:microbiology; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D053532:Xanthomonas axonopodis / Q000254:growth & development*
D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S