Antifungal activity of plant extracts against Fusarium oxysporum – the cause of corm-rot disease of Gladiolus

Fusarium oxysporum f.sp. gladioli (Massey) Snyd. & Hans. was isolated from diseased corms of gladiolus (Gladiolus grandiflorus sect. Blandus) cv. Aarti. Antifungal activity of different concentrations (2, 4, 6 and 8% w/v) of leaf extracts of wheat (Triticum aestivum L.), maize (Zea mays L.), sunflower (Helianthus annus L.), chilies (Capsicum annum L.), onion (Allium cepa L.) and marigold (Tagetes erectus L.) was evaluated against in vitro growth of F. oxysporum. Extract of marigold, sunflower and chilies were found highly effective where all the employed extract concentrations significantly reduced fungal biomass by 54-79%, 33-85% and 45-57%, respectively. In case of onion, only the highest concentration of the extract i.e. 8% significantly suppressed fungal biomass by 73%.