East African highland banana production as influenced by nematodes and crop management in Uganda

Abstract

Production loss caused by nematodes in East African highland banana was evaluated at Sendusu, near Kampala in Uganda, 1120 m above sea level. The commonly grown cultivar, Mbwazirume, was grown in nematode-infested and non-infested plots under heavily mulched, clean-weeded and millet-intercropped management regimes. Influence of the different treatments was evaluated over the second to the fourth crop cycle and management was observed to have the greatestinfluence on production. The non-infested heavily mulched plots produced 16.1 tonnes per ha per cycle compared with the clean-weeded and non-infested millet-intercropped plots only 5.6 and 5.3 tonnes per ha per cycle, respectively. Presence of Radopholus similis and Helicotylenchus multicinctus reduced the average production in the well mulched, clean-weeded and millet-intercropped plots by 30%, 32% and 38%, respectively. The nematode-induced loss is a result of a reduction of bunch weight, a reduction of flower production and an increase in plant toppling. When plant toppling occurred on a mat, the chance was highly reduced that this mat produces a harvestable bunch in the following cycle. Damage by the banana weevil, Cosmopolites sordidus, was higher in nematode-infested plants compared with noninfested plants. Itmay be thatin nematode-infested plants, weevil larvae are more successfulin developing or thatadultweevils prefernematodeinfested plants for egg disposal. No interaction between Black Sigatoka and nematode infestation was observed.