Biological control of Physalis divericata L. by plant pathogens in Lorestan province

To obtain pathogenic fungal isolates from Physalis divericata L., the plants showing the symptoms of fungal diseases were collected from different areas in Lorestan and were transported to the laboratory in year 2009. The samples, after surface disinfection, were cultured on PDA and V-8 media. Based on fungi keys identification, two species including Alternaria alternata and Fusarium sp. were identified. The pathogenicity and virulence of identified fungal pathogens at 105, 106, 107 and 108 spores per mL of distilled water were tested on Physalis divericata at different growth stages (cotyledon, 4, 6 and 9-11 leaf). Host range tests were conducted on beans, corn, sugar beets and soybeans under greenhouse conditions. Results showed that Alternaria alternata isolate A6 induced more severe disease than other Alternaria isolates and Fusarium sp. Physalis divericata was more sensitive to Alternaria alternata isolate A6 at 6 leaf-stage, especially at 108 spore per ml distilled water. Non of the target crops showed any symptoms due to inoculation by Alternaria alternata isolate A6.