National Symposium on Strategic Issues in Plant Pathological Research held at Department of Plant Pathology, CSK HP Krishi Vishvavidayalaya, Palampur on November 24–25, 2011
Biocontrol control of plant disease is gaining importance in recent years as the chemical control creates serious environmental pollution and public health hazards. Search of effective biocontrol agents, in our present study yielded in isolation of indigenous strains of Pseudomonas species from the normal and replant rhizospheric soil of apple and pear orchard of Kullu District (H.P.). Isolates from apple and pear rhizospheric soil were characterized on the basis of their morphological, physiological, biochemical and plant growth promoting activities such as: (a) the ability to produce plant hormone viz. auxins, gibberellins and cytokinins; (b) asymbiotic N2 fixation; (c) solubilization of inorganic phosphate and mineralization of organic phosphate and/or other nutrient and (d) antagonism against phytopathogenic microorganisms by production of siderophore, the synthesis of antibiotics, enzymes, HCN production and production of antifungal metabolites. Identified, bacterial isolates of fluorescent Pseudomonas showed broad spectrum antifungal activity against Fusarium oxysporium, Rhizoctonia solani, Sclerotium, Alternaria, Pythium and Dematophora. In vitro antifungal study revealed that two isolates An-1-kul and An-13-kul showed maximum inhibition against all the test indicator fungi. These two isolates may be used in agricultural and horticultural crops to promote plant growth and biological control alternatives to extensive use of chemical pesticides.
