Challenges and opportunities for macropropagation technology for Musa spp. among smallholder farmers and small-and medium-scale enterprises

Lack or shortage of healthy and improved planting material is a major constraint to the expansion of banana and plantain production. The situation is made worse by the lack of formal systems for producing and distributing quality planting material, thereby forcing farmers to depend on natural regeneration of plants for their supply. This is usually a very slow process, and produces small amounts of planting material that are likely to be contaminated with soil-borne pathogens such as nematodes. To overcome this constraint, several techniques have been developed to rapidly multiply banana and plantain planting material, including micropropagation under aseptic conditions in the laboratory. While micropropagation techniques can provide large amounts of planting material, they are not adapted to the conditions of smallholder farmers. Therefore, user~friendly techniques that require little technical skill or equipment would prove more attractive to adoption by such farmers. The International Institute of Tropical Agriculture (UTA) has been looking at alternative means of producing planting material for wide~scale distribution of improved banana and plantain cultivars. The alternative methods are classified into two categories: field techniques based on complete or partial decapitation of suckers; and the macropropagation of suckers practised away from the field. Treatment of suckers to reduce the risks of transmitting soil-borne contaminants is strongly recommended and forms an integral component of the dissemination package for smallholder farmers. Macropropagation techniques, although genotype dependent, can produce 8-15 new plants/corm within 15 days, while secondary scarification of newly emerging buds has the potential to further increase the number of plantlets by a factor of 2-3, within the same time frame. Plantlets obtained
through this method have the uniformity of micropropagated seedlings while being less prone to post-establishment factors in the field. This method is simple and cheap, although it requires some minimum investment to set up propagators and weaning facilities, so it is suitable for small- and medium-scale enterprises. However, its utilization is undermined by several factors, the most critical of which are lack of initial capital investment and technical skills.