Morphological and cultural characterization of Alternaria alternata (Fr.) Keissler blight of gerbera (Gerbera jamesonii H. Bolus ex J.D. Hook)

Abstract

Fungal blights are among the major concern for limiting the cultivation and production of many ornamental and flowering plants. Gerbera is an important cut flower with great export potential. However, it is infected by many pathogens in the protected cultivation. The severe infection of fungal blight caused by Alternaria alternata (Fr.) Keissler was observed in the polyhouse condition. Hence, in this study, critical morphological and cultural studies were done to understand the pathogen behaviour. The fungus A. alternata produced profuse mycelium on Potato Dextrose Agar (PDA) with an average width of 4.42 ?m in diameter, conidiophores, conidia and intercalary chlamydospores measured as 42.26 x 4.29 ?m, 47.16 x 13.49 ?m and 7.22 ?m in diameter, respectively. The synthetic media viz., Leonions’s agar, Glucose-peptone agar and Sabourand’s agar and non-synthetic media, Oat meal agar and PDA were excellent for the mycelial growth and conidial production of A. alternata.