Decision support system for late blight in tomato and potato

The most destructive tomato and potato disease is late blight, caused by Phytophthora infestans. Late blight causes damage through reduction in productivity when the pathogen attacks and destroys the crop. It is also the cause of increasing production costs, because it requires frequent fungicidal sprays. Consequently, there is also the exposure of crop workers, consumers and the environment to chemicals. The aim of this project is to develop a sensing system to assist in decision making about the best time to apply fungicides. A sensor prototype was assembled using temperature, humidity and pluviometer sensors attached to bluetooth development kits. The initial hardware prototype was assembled using a development kit, and the communication protocol between the sensor and the application was defined. The application was developed based on the Blitecast forecasting system, where the first forecast is given according to the severity identified over a period that precedes the current date. From the moment the first positive prediction of the disease is identified, a recommendation for fungicide application is generated. The system was validated in laboratory and field tests. The prototype was installed next to two commercial tomato greenhouses and the data were compared to those of the current management's. During the cultivation period the producer made 7 preventive applications without verifying whether the disease was present or not. For the same period, the system recommended 3 applications, showing a difference of the saving of 4 applications. The prototype proved to be feasible in the first phase. We started the second phase, in which we are manufacturing the sensor to be evaluated for tomato and potato. The expected result is a quick and easy disease management system that will assist producers to decide the best time to start disease control. It can avoid unnecessary sprays, reducing costs for the producer and reducing the risks of severe epidemics and environmental pollution.