MICROPROPAGATION OF TWO BANANAS (MUSA SPP.) VARITIES USING SHOOT EXPLANT FROM GURAGE ZONE, ETHIOPIA

Abstract

The banana (Musa spp.) is one of the most important fruits for production and consumption due to its great nutritional importance. Nearly all banana genotypes are being threatened by bacterial wilt disease due to conventional propagation. Banana propagation rates achieved by tissue culture techniques are much higher than those reported by conventional methods. The objectives of this research were to develop a mass in vitro regeneration protocol for two elite banana dwarf Cavendish and ducase varieties from shoot tip explants. The experiment was laid out in CRD with three replications in factorial arrangement. Sodium hypochlorite (NaOCl) in three concentration levels (1, 2, and 5%) with 70% ethanol was used for surface sterilization. For controlling browning on explants at shoot initiation, explants were aseptically cultured on MS basal medium supplemented with 25mg, 50mg, ascorbic acid, and 1g and 2g of activated charcoal. Then the initiated shoots were transferred to MS basal media supplemented with 2, 2.5, or 3 mg/l of BAP alone and in combination with 0.5 mg/l of Kn. Plantlets were planted on different mixes of soil in (2:1:1). The sterilization experiment showed that 2% NaOCl was found to be effective. The results showed that from levels of antioxidant treatments up to 85%, initiated shoots survived medium containing 2 g/l activated charcoal. The use of 2g AC and 50mg AA as anti-browning agents in the medium for banana explants was suitable for shoot tip culture. On the shoot multiplication, maximum shoots per ex-plant (8.33) were obtained on a medium containing 3 mg/l BAP and 0.5 mg/L KN. The highest increase in root length was observed with the 80 g/l bulla, resulting in 6.90cm on the du case variety. The acclimatization experiment showed 100% plantlet survival in all media mixtures. In this study, among the two cultivars tested, dwarf Cavendish was found to be more responsive to in vitro propagation techniques.