INFLUENCE OF TWO FARMING SYSTEMS ON THE PRODUCTIVITY OF WATERMELON

Abstract

The investigation was carried out in 2023-2024 in the experimental field of the Department of Plant Production, Technical University - Varna. The Crimson sweet watermelon variety was cultivated in two farming systems: organic and conventional. In organic farming, two fertilizers are used - compost and Isabion. In the conventional farming were used - YaraMila Complex and N15P15K15 + 11 S. The results show that the total vegetative weight is highest in Compost + Isabion (860 g), followed by the independent application of Isabion (725.3 g), and the index was 476 g for the untreated control.
When comparing the two fertilization systems, the yield is higher in the conventional system (9234 kg/da for YaraMila+Isabion). In the organic system, yields of 5,287 kg/da (Compost+Isabion) and 4,965 kg/da (Isabion) were recorded.
Cucurbit powdery mildew and cotton aphid were observed in watermelon during growing season. Plant protection in organic farming included two applications of fungicide Taegro and insecticide Afitek. In conventional farming was used fungicides Cideli Top and Zoxis, and insecticides Decis and Afinito. The results demonstrated that disease incidence of powdery mildew and density coefficent of cotton aphid were significantly lower after the pesticides application in the two farming systems than the untreated control.