ABSTRACT
With the aim of studying the epidemiology of Botrytis leaf blight, caused by Botrytis squamosa in the region of Alto Vale do Itajaí, Santa Catarina State, Brazil, an assay was conducted with naturally infected plants in 2017 and 2018 growing seasons. Every seven days, for 10 weeks, the population of conidia in the air was quantified, the environmental conditions were recorded and the severity in plants was evaluated. Even in an environment favorable to the disease, its onset occurred five weeks after sowing. The epidemic started one week after the first detection of inoculum in the air in 2018. The disease progress was represented by the Gompertz model y=0.51830*(exp(-5.95660*exp(-0.47392*x))). Fresh biomass production of seedlings was 1.68 and 2.8 grams per plant in the respective evaluation years. This epidemiological study can provide information about the beginning of the epidemic and will be useful in the validation of a forecasting system for Botrytis leaf blight in onion.
Keywords
Allium cepa; epidemiology; Botrystis squamosa
