A rapid microbioassay for discovery of antagonistic bacteria for Phytophthora parasitica var. nicotianae.
Phytopathology
; 102(3): 267-71, 2012 Mar.
Article
in En
| MEDLINE
| ID: mdl-22046969
ABSTRACT
A simple, rapid, small-scale microbioassay for infection of tobacco seedlings by Phytophthora parasitica var. nicotianae was developed here. This assay uses tobacco seedlings cultivated in petri dishes for a standardized method for quantitation of initial zoospore inocula and high-throughput screening of antagonistic bacteria. Zoospore inocula between 10(2) to 10(5) spores per petri dish were inoculated on 14-day-old tobacco seedlings for the susceptibility test. The optimum inocula was established to be ten thousand zoospores. One hundred and fifty pure culture bacteria with different pigments, growth rates, and morphologies were isolated from rhizosphere soil of tobacco and screened for protective ability against tobacco black shank. Fifteen bacteria presented high activity against P. parasitica on tobacco seedlings. They were identified by Biolog GEN III MicroPlate and distributed as Bacillus amyloliquefaciens, B. licheniformis, Paenibacillus pabuli, B. atrophaeus, B. subtilis, B. pumilus, and B. endophyticus, respectively. Four antagonists chosen randomly from the 15 bacteria all exhibited the same 100% protective activity in planta as that in the petri dishes. This microassay proved to be a rapid, reproducible, and efficient method for screening of potential biological agents or microorganisms and may be useful for studying mechanisms of infection and control of Phytophthora spp. under hydroponic conditions.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Phytophthora
/
Soil Microbiology
/
Bacillus
/
Nicotiana
/
Biological Assay
/
Paenibacillus
Language:
En
Journal:
Phytopathology
Journal subject:
BOTANICA
Year:
2012
Type:
Article