Resistance of Banana Seedlings (Musa acuminata spp. banksii and M. acuminata spp. breviformis) to Fusarium Wilt Disease

Fusarium wilt of banana which is also known as Panama disease caused by Fusarium oxysporum f. sp. cubense (Foc), is a soilborne systemic disease which occludes host vascular system. There is a method to screen Fusarium wilt in banana seedling with double-tray technique under greenhouse condition. The aim of this research was to evaluate banana seedlings resistance to Fusarium wilt disease. We used two cultivars of banana seedlings, Musa acuminata spp. banksii and M. acuminata spp. breviformis in this experiment. Two-months-old seedling (10-15 cm tall) were suitable for differential disease symptom expression, and gave similar results to field evaluations. Seedlings with vigorous root systems were gently removed from the growth tray and were immersed in Foc spores suspension for two hours with a wide range of concentrations in spores/ml (7x10, 7x102. 7x103, 7x104, 7x105, 7x106). Each treatment was replicated five times and this experiment was observed for 28 days. Evalution of disease severity on 28th day was based on the Leaf Symptom Index (LSI) and Rhizome Discolorization Index (RDI). M. acuminata spp. banksii showed foliage and rhizome symptoms at inoculum concentrations higher than 7x10 spores/ml, with the highest DSI scales for LSI was 3.8 and DSI scales for RDI was 6.0 at concentrations 7x104 spores/ml. M. acuminata spp. breviformis showed those symptom at inoculum concentrations higher than 7x103 spores/ml, with the highest DSI scales for LSI was 5.0 and DSI scales for RDI was 8.0 at concentrations 7x106 spores/ml. Keywords Double-tray technique, Fusarium wilt, M. acuminata spp. banksii, M. acuminata spp. breviformis, resistance. Proceeding Iboc 2014: Biotechnology, Agriculture and Food Technology. 2015. II. 156-161