Farmer Participatory Evaluation of the Potential for Organic Vegetable Production in the Wetlands of Zambia

Abstract

Although wetlands (locally called dambos) are considered extremely vulnerable to poor agricultural practices, rising population pressures have caused their agricultural use to become increasingly important. Intensification of dambo use by way of chemical fertilizer and pesticide applications poses serious challenges to their ecological sustainability. This study evaluated gliricidia (Gliricidia sepium) leafy biomass as a possible alternative to commercial fertilizer, and Tephrosia (Tephrosia vogelii) leaf extract, commercial formulations of neem seed extract (Achook) and Bacillus thuringiensis (Thuricide) as alternatives to chemical pesticides in the production of cabbage in dambos. The study showed that soil fertility management practices can significantly influence the time to harvest the cabbage crop and its yield. Vegetables grown using gliricidia biomass produced significantly higher yields compared with the no-input option. The population density of diamondback moth (Plutella xylostella) larvae, the percentage of plants infested by cabbage webworm (Hellula undalis) and cabbage aphid (Brevocoryne brassicae) was significantly lower in cabbage treated with sprays of Tephrosia leaf extract and Achook. It is concluded that gliricidia leafy biomass as a soil fertility management practice combined with Tephrosia leaf extract and neem seed extract as a crop protection practice could increase the productivity of cabbage and ensure sustainable utilization of dambos.

Keywords

dambos legume biomass biopesticides sustainability

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