Increasing Incidence of Cigar End Rot Disease is Compromising Recent Gains in Banana Production in Kenya
Bananas are one of the most important crops for income generation in Central and Eastern Kenya. In these regions, dessert varieties have traditionally been most widely grown with cultivar Gros Michel having dominated until the 1990s, when increasing infection by panama disease (Fusarium oxysporum f.sp cubense) caused a significant decline in orchard productivity. Measures to support recovery of banana farming were initiated with the trust being introduction of the Fusarium resistant Cavedish varieties, predominantly the Giant cavedish types (Grand nain, Williams). Although the adoption rates for these varieties has been modest, largely due to the high cost of tissue cultured seedlings, the cavedish types currently dominate commercially oriented banana orchards. In the recent past increased incidence of cigar end rot has been observed with devastating severity on the cavedish types. The disease has established widely in banana orchards in the mid altitudes regions especially Kiambu, Thika and spreading further in the surrounding districts. Preliminary observations indicate incidence is over 50% (no. of mats diseased) with aggravated severity during warm moist periods. Infected fruits turn grey from the tips resembling burning cigarette. Most commonly infection starts from the youngest fruits where the attached bracts of the male buds may continue to shade the fingers thus creating suitable microclimates in which the pathogen proliferates. Once a bunch has been infected its market value declines drastically since buyers prefer whole bunches that are easier to package for transportation and ripening. Although there is increasing shift to weight based marketing whereby fingers can be detached and sold individually or as a cluster, presentation of produce as a whole bunch commands premium. Infection of fingers at early stages of growth induces premature ripening and creates opening for other organisms that may aggravate the damage. In response to this threat, farmers have been advised to remove the male buds promptly as soon as the last fingers form. Farmers are also increasingly applying fungicides to protect the bunch. Considering that a bunch matures over several weeks, numerous sprays are often required before the bunch can be harvested. This practice has a downside in that the cost of applying fungicides eats into expected profits and further, the presence of fungicide sprays on fruits may turn away potential clients. There is need to include cigar end rot among the priority diseases in research and extension programmes to support sustainable growth and profitability of banana farming in Kenya.