Enhancing Dissemination of Soil and Water Research Outputs of SADC Universities
The study was conducted to evaluate effects of conservational tillage on vegetable production on the northeastern part of Uluguru Mountains in Tanzania. Six treatments such as control conservational tillage; conservational tillage with manure; conservational tillage with insitu composting; control traditional tillage; traditional terrace with manure and traditional tillage with in situ composting were examined. Nutrient levels were determined from soil before and after harvest and from plant samples after harvest. Soil losses were assessed by collecting runoff using polyethylene troughs for each treatment. Analysis of variance and Multiple range test (P=0.05) was done to test the effect of the treatments. The differences (P=0.05) on soil loss, plant nutrient status and vegetable yield were observed. All conservational treatments gave high fresh yield (4.3–44.7 ton/ha), high nutrient retention (N% 0.11–0.14, P% 5.17– 16.33, K% 0.33-0.36) and experienced low soil losses (0.49, 0.54 to 0.65 ton/ha/season). While the opposite was true for traditional treatments lower fresh yield (0.9–13.9 ton/ha), low nutrient retention (N% 0.10–0.11, P% 0.91–4.00 and K% 0.29–0.32) and high soil losses (0.54, 0.83 to 1.26 ton/ha/season) at P=0.05. It was concluded from this study that the conservational tillage for vegetable production on sloping land ranging from 20 to 80 percent was the best practice resulting in increased crop yield, nutrient uptake, plant nutrient retention, and reduced soil loss.