Development of a warning system for wheat blast caused by Pyricularia grisea

摘要: Wheat (Triticum aestivum L.) blast caused by Pyricularia grisea is a new disease in Brazil and no resistant cultivars are available. The interactions between temperature wetness durations have been used many early warning systems. Hence, growth chamber experiments to assess the effect of different temperatures (10, 15, 20, 25, 30 35oC) duration spike-wetness (0, 5, 10, 30, 35 40 hours) on intensity cultivar BR23 were carried out. Each formed an experiment treatments. highest was observed at 30°C increased as wetting period while lowest occurred 25°C 10 hours spike wetness. Regardless temperature, symptoms when less than but h exceeded 85%. These variations function explained generalized beta model Gompertz model. Disease modeled both resulting equation provided precise description response P. This construct tables that can be predict wheat based obtained field.