Effect of endophytic Fusarium oxysporum on growth of tissue-cultured banana plants

Abstract

Endophytes which are mutualistic symbiots living asymptomatically within plant tissues have been reported to have beneficial effects on plant growth. In bananas a wide diversity of endophytic fungi have been isolated from healthy plants, where Fusarium oxysporum has been documented as the dominant species. The effects of three endophytic F. oxysporum isolates (V5W2, Emb2.4o and Eny7.11o) originating from Uganda on the growth of tissue-cultured banana plants was evaluated under Kenyan conditions in screenhouse trials. Dessert banana cv. Giant Cavendish and cv. Grand Naine were inoculated with the endophytic isolates two months after weaning and growth evaluated for a period of six months. Plant responses to endophyte treatment was assessed on plant height, girth, number of functional leaves, length and width of the youngest leaf, and shoot and root weights. Improved growth of all parameters was observed for plants inoculated with endophytes when compared to the control plants. Although the differences were not significant, up to 11.3% increase in plant height, 8.3% increase in girth, 7.5% increase in shoot weight and 11.5% increase in root weight resulted for endophyte-inoculated plants when compared to the control plants. The study shows that endophytes may have potential to enhance growth of tissue-cultured banana plants.