Mycorrhiza and Tissue-Culture Banana Production

Bananas and plantains are widely grown in tropical countries by smallholder farmers who depend on them for their livelihood. In Kenya the crop is harvested throughout the year and ensures food and income security thus playing an important role in poverty alleviation. In recent years there has been a rapid decline in banana production, due mainly to declining soil fertility, pests and diseases, drought and poor planting materials. In vitro tissue cultured (TC) bananas are increasingly replacing conventional planting material which provide disease-free quality plants, but which are also free of beneficial microbes such as arbuscular mycorrhizal fungi (AMF). A two-factor experiment comprising of nine banana cultivars and five treatments was laid out in RCBD. Plants were inoculated at the hardening stage. Three destructive harvests were done at 8, 18 and 22 weeks after transplanting. Plant growth parameters were recorded, assessment of mycorrhizal colonization and plant shoot nutrient done at each harvest. Treatment effects were tested using GLM with GENSTAT version 8. Means were separated by Fisher's test (p <= 0.05). Banana plantlets inoculated with Glomus spp. performed better than those inoculated with Gi. albida and the non-mycorrhized plants in all growth parameters. Variations in cultivar response to AMF spp. were observed. Response to inoculation depends on both the plant and AMF spp. The increase in colonization by the Glomus spp. resulted into these plants absorbing more nutrients from the rhizosphere hence improving the nutrient status of these plants. Bananas are dependent on mycorrhizas hence their inoculation at the hardening stage may improve banana adaptation in harsh environments resulting in increased banana production hence poverty alleviation.