| Sumario: | 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.
|
|---|