Diagnosis of diseases in the spray rose (Rosa spp) crop of the Tucán Flowers S.A. marketing company in the municipality of Cogua, Cundinamarca

Abstract

Rose cultivation is important to the Colombian economy as a source of income. However, it is affected by several pathogens, which generate low production yields due to poor flower quality. The main diseases include powdery mildew and downy mildew. To characterize the causative agents of these diseases, a sampling was conducted at the Tucán Flowers marketing company in Cogua, Cundinamarca. This company produces and exports spray roses. The incidence and severity of the diseases and nutritional deficiencies found were evaluated. A total of 540 plants were sampled, corresponding to 0.25% of the three randomly selected significant areas of the crop. The signs and symptoms of each abnormality were observed and recorded. Plant material was then collected to diagnose the causative agent of the diseases using a humidity chamber and direct imprinting. Nutritional deficiencies were determined from literature. The results show a high incidence of powdery mildew at 39.44%, followed by downy mildew at 27.96%; however, the severity percentage is not significant. The causative agents of powdery mildew were identified as Oidium sp. and downy mildew as Peronospora sp. Nutritional deficiencies of potassium, iron, and boron, among others, were also observed.