Evaluating Horticultural Practices for Sustainable Tomato Production in Kamuli, Uganda

Tomatoes are a source of income and contribute to food security for small-landholder farmers in Uganda, including the Kamuli District. Evaluation of sustainable production practices is needed to improve farmers’ livelihoods. Four treatments and their objectives were included in the study; 1) evaluate three tomato cultivars (Heinz 1370, Nuru F1, and MT 56) for disease resistance and potential yield, 2) quantify any effect of pesticide applications on tomato yield, 3) compare staking practices’ impact on disease occurrence, and 4) evaluate the influence of mulching on disease occurrence and yield. The experimental design was a randomized complete block design with a factorial and split-plot arrangement of treatments during two growing seasons of 2013. Total and marketable number of fruit, marketable fruit weight, gross margin, and disease severity were measured for each treatment.  Disease severity was assessed using the area under the disease progress curve.  In season one, results indicated that disease-resistant cultivar MT 56, in combination with pesticide application and soil mulch, provided the greatest marketable fruit number and marketable fruit weight, and all treatments had a positive gross margin.  In season two, a combination of ‘Nuru F1’, pesticides and mulch produced the greatest total and marketable fruit number, and fruit weight.  A combination of ‘MT 56’, no pesticide application, and no mulch was the only treatment with positive gross margin in the second season.  Applying pesticides reduced disease severity of early blight, Alternaria solani, for all cultivars in season one and for Heinz 1370 and Nuru F1 in season two, but did not affect disease severity for MT 56 in the second season. Using soil mulch reduced the severity of early blight disease, but decreased the gross margin when purchased. Staking did not affect yield or disease severity of plants and decreased the gross margin.  Based on these results, we recommend tomato growers produce ‘MT 56’.  Applying pesticides according to label recommendations and using soil mulch may increase yields and protect tomato plants and fruits from A. solani depending on cultivar and season.  The availability of ‘MT 56’ tomato seed makes implementing the recommended cultivar, MT 56, difficult.  Follow-up studies are being conducted to analyze the tomato seed value chain in Uganda to understand the availability of superior cultivars and hybrids.