FUSARIUM PROLIFERATUM, THE MAIN CAUSE OF CLOVE ROT DURING STORAGE, REDUCES CLOVE GERMINATION AND CAUSES WILT OF ESTABLISHED GARLIC PLANTS

Abstract

Eight fungal species belonging to six genera, i.e. Aspergillus niger , Aspergillus ochraceus , Botrytis alli , Fusarium oxysporum , Fusarium proliferatum , Penicillium purpurogenum , Rhizopus stolonifer and Stemphylium botryosum , were isolated from decayed garlic cloves. F. proliferatum had the highest frequency of occurrence and was found to be highly pathogenic to garlic cloves. The other fungal species were less frequent and aggressive. Garlic bulbs (cvs Balady and Sides 40) were stored at room temperature and at 5°C for six months after harvest. It was observed that clove rot and its severity increased with time in both cultivars and storage conditions. Rot incidence and severity were highest in cv. Balady at room temperature. In pot experiments, inoculation of garlic cloves with F. proliferatum before planting affected the percentage of plant emergence and severe wilt symptoms developed gradually on the surviving plants. Isolation from selected seedlings showing wilt symptoms yielded the same F. proliferatum that had been used for inoculation. The optimum temperature for F. proliferatum growth was 25°C, maintained for nine days. In in vitro assays Carbendazim had a strong inhibition effect of fungal growth followed by Metalaxyl 8%+Mancozeb 64% and thiophanate-methyl. The bioagents Trichoderma harzianum , T. viride , T. koningii , T. virens and T. album inhibited F. proliferatum growth.