Efficacy of Selected Fungicides in Management of Tomato Fungal Diseases

Abstract

Tomato (Solanum lycopersicum L.), known to belong to the Solanaceae family, is considered one of the most important vegetables in the world since the fruits are widely consumed either fresh or processed. However, tomato yields in Uganda are low due to several fungal diseases among other factors like poor agronomic practices. There is not yet any other effective alternative control method to chemicals in control of tomato fungal diseases. However careless or excessive use of pesticides can result in poor control, crop damage and hazards to healthy and environment. The aim of this study was to determine efficacy of newly introduced fungicides in management of tomato fungal diseases. The experiment studied four fungicides i.e. Azoxistrobin, Mancozeb 80% WP, Metalaxyl+Mancozeb and Mancozeb 640g/kg + Cymoxanil 80g/kg against an untreated control. The treatments were laid out in a randomized complete block with three replications. The study was conducted at Makerere University Agricultural Research Institute Kabanyolo (MUARIK). The major fungal diseases studied were late blight, early blight, powdery mildew and downy mildew. Treatments were applied 10 days after planting. Data was collected 15 days after planting and then continued every after two weeks up to harvesting on 10 randomly sampled plants per plot. At harvest, fruit weight was recorded by weighing the fruits obtained per plot using a weighing balance considering three harvesting times. Results showed that Azoxystrobin provided the best control for late blight and early blight, Metalaxyl+Mancozeb and Mancozeb 640g/kg + Cymoxanil 80g/kg controlled powdery mildew and downy mildew respectively better than other treatments. This information is relevant to tomato growers in Uganda who aim at increasing productivity. Further studies are required on efficacy on other crops to provide concrete recommendations.