Effect of Alternaria helianthi on disease development, germination and seed quality in sunflower

• Published in: Pak. J. Agri. Engg., Vet. Sci. Vol. 22; no. 1; pp. 26 - 29
• Main Authors: Wagan, K.H. (Sindh Agriculture Univ., Tandojam (Pakistan). Dept. of Plant Pathology), Pathan, M.A. (Sindh Agriculture Univ., Tandojam (Pakistan). Dept. of Plant Pathology), Jiskani, M.M
• Format: Journal Article
• Language: English
• Published: 01.06.2006
• Subjects: ALTERNARIA HELIANTHI; DISEASE CONTROL; FUNGAL DISEASES; FUNGICIDES; GERMINATION; HELIANTHUS ANNUUS; LIPID CONTENT; PATHOGENICITY; PROTEIN CONTENT; SEEDS
• ISSN: 1023-1072

Alternaria helianthi (Hansf.) Tubaki and Nishihara were isolated from infected leaves and seeds of sunflower variety, HO-1. The fungus was identified on its colony characteristics and morphology of conidia. Pathogenicity test of the fungus was conducted on 8-week old plants of sunflower var. HO-1 grown in earthen pots containing steam-sterilized soil. The typical dark circular spots of the fungus were developed on plants, injured before inoculation with spore suspension of the fungus. The spots were greater in number and size on injured plants than on uninjured inoculated plants. The germination and height of plants were significantly reduced grown from inoculated seeds as compared to uninoculated seeds. The sunflower seeds infected with A. helianthi were lower in weight, oil and protein content than healthy seeds. The number of leaf spots developed on inoculated leaves were significantly reduced by spraying the sunflower plants with Vitigran blue followed by Dithane M-45, Liro-Manzeb and Topsin-M.