Assessment of airborne Curvularia propagules in the atmosphere of Havana, Cuba

Even though the presence of Curvularia conidia in the tropical air and the role in respiratory allergy symptoms or plant diseases incidence has been reported, traditional aerobiological investigations usually do not consider their profound study. An aeromycological study of the Curvularia propagules in Havana was conducted during the years 2017 and 2018. Monitoring was carried out by means of volumetric viable and non-viable methodologies. Three types of microscopically identifiable airborne spores (Lunata, Geniculata and Maculans) were identified, according to their distinctive features (conidium shape, pigmentation, number and position of the septa), defined by optical microscopy with 400 x magnification. The spores of Curvularia showed prevalence during rainy months and were predominantly abundant through the daytime. The annual distribution showed the prevalence of the Lunata type, with a diurnal pattern and corroborated through the isolated species since all belonged to this morphological group. The average temperature and relative humidity, as well as the precipitations, correlated positively with the concentrations. The wind speed showed a negative correlation, which indicates that the climatic conditions of the Havana influence the aerobiological dynamics of airborne Curvularia propagules.