title: Influence of mineral amendment on disease suppressive activity of Pseudomonas fluorescens to Fusarium wilt of chickpea.
abstract: Fusarium wilt caused by Fusarium oxysporum f. sp. ciceri causes considerable yield loss of chickpea. Pseudomonas fluorescens4-92 (Pf4-92) strain can suppress the disease. Amendment of zinc EDTA and copper EDTA could not suppress the disease significantly when used alone; however, they significantly suppressed the disease in presence of Pf4-92. In vitro observation showed that at 40, 30 and 20microgml(-1) concentrations of these minerals, i.e. Zn, Cu and Zn plus Cu, respectively, completely repressed the production of the phytotoxin, fusaric acid (FA). FA concentration (0.5microgml(-1)) has been shown to suppress the production of 2,4-diacetylphloroglucinol (DAPG) by Pf4-92, and DAPG, salicylic acid, pyochelin and pyoluteorin production was enhanced by these mineral amendments. In rockwool bioassays, Zn, Cu and Zn plus Cu amendments reduced FA production and enhanced DAPG production. This study demonstrates that Zn and Cu enhance biocontrol activity by reducing FA produced by the pathogen, F. oxysporum f. sp. ciceri.
authors.affiliation: National Bureau of Agriculturally Important Microorganisms (NBAIM), Kushmaur, Mau 275 101, Uttar Pradesh, India. ratulsaikia@yahoo.com
authors.forename: Ratul
authors.initials: R
authors.lastname: Saikia
authors.forename: Saju
authors.initials: S
authors.lastname: Varghese
authors.forename: Bhim Pratap
authors.initials: BP
authors.lastname: Singh
authors.forename: Dilip K
authors.initials: DK
authors.lastname: Arora
mesh_terms: D000898:Antibiosis / Q000187:drug effects*; D029863:Cicer / Q000254:growth & development / Q000382:microbiology*; D003300:Copper / Q000494:pharmacology; D005669:Fusaric Acid / Q000037:antagonists & inhibitors / Q000378:metabolism / Q000494:pharmacology; D005670:Fusarium / Q000254:growth & development / Q000378:metabolism* / Q000472:pathogenicity; D008903:Minerals / Q000494:pharmacology*; D010636:Phenols / Q000378:metabolism; D010696:Phloroglucinol / Q000031:analogs & derivatives / Q000037:antagonists & inhibitors / Q000378:metabolism; D010935:Plant Diseases / Q000382:microbiology*; D011551:Pseudomonas fluorescens / Q000378:metabolism*; D011758:Pyrroles / Q000378:metabolism; D020156:Salicylic Acid / Q000378:metabolism; D013844:Thiazoles / Q000378:metabolism; D015032:Zinc / Q000494:pharmacology
chemical_list: D008903:Minerals; D010636:Phenols; D011758:Pyrroles; D013844:Thiazoles; C095503:pyoluteorin; C025316:pyochelin; D003300:Copper; C059817:2,4-diacetylphloroglucinol; D010696:Phloroglucinol; D015032:Zinc; D005669:Fusaric Acid; D020156:Salicylic Acid