title: Involvement of secondary metabolites and extracellular lytic enzymes produced by Pseudomonas fluorescens in inhibition of Rhizoctonia solani, the rice sheath blight pathogen.
abstract: Fourteen strains of Pseudomonas fluorescens isolated from rhizosphere soil of rice were tested for their antagonistic effect towards Rhizoctonia solani, the rice sheath blight fungus. Among them, PfMDU2 was the most effective in inhibiting mycelial growth of R. solani in vitro. Production of chitinase, beta-1,3-glucanase, siderophores, salicylic acid (SA) and hydrogen cyanide (HCN) by P. fluorescens strains was evaluated. The highest beta-1,3-glucanase activity, siderophore production, SA production and HCN production were recorded with PfMDU2. A significant relationship between the antagonistic potential of P. fluorescens against R. solani and its level of beta-1,3-glucanase, SA and HCN was observed.
authors.affiliation: Department of Plant Pathology, Agricultural College and Research Institute, Tamil Nadu Agricultural University, Madurai 625104, Tamil Nadu, India.
authors.forename: M
authors.initials: M
authors.lastname: Nagarajkumar
authors.forename: R
authors.initials: R
authors.lastname: Bhaskaran
authors.forename: R
authors.initials: R
authors.lastname: Velazhahan
mesh_terms: D000898:Antibiosis; D000935:Antifungal Agents / Q000378:metabolism / Q000494:pharmacology; D002688:Chitinases / Q000378:metabolism / Q000494:pharmacology; D004798:Enzymes / Q000378:metabolism / Q000494:pharmacology*; D043326:Glucan 1,3-beta-Glucosidase / Q000378:metabolism / Q000494:pharmacology; D006856:Hydrogen Cyanide / Q000378:metabolism / Q000494:pharmacology; D025282:Mycelium / Q000187:drug effects / Q000254:growth & development; D010572:Pest Control, Biological / Q000379:methods; D011551:Pseudomonas fluorescens / Q000201:enzymology / Q000302:isolation & purification / Q000378:metabolism*; D012232:Rhizoctonia / Q000187:drug effects* / Q000254:growth & development*; D020156:Salicylic Acid / Q000378:metabolism / Q000494:pharmacology; D017262:Siderophores / Q000032:analysis / Q000378:metabolism / Q000494:pharmacology; D012988:Soil Microbiology
chemical_list: D000935:Antifungal Agents; D004798:Enzymes; D017262:Siderophores; D006856:Hydrogen Cyanide; D002688:Chitinases; D043326:Glucan 1,3-beta-Glucosidase; D020156:Salicylic Acid