Viabilidade econômica do coletor de esporos no monitoramento do agente causal de ferrugem-asiática da soja (Phakopsora pachyrhizi) para o controle químico da doença

Abstract

Soybean (Glycine max) is one of the main agricultural crops in Brazil, with great economic and social relevance. However, the crop’s productivity is constantly threatened by Asian soybean rust, caused by the fungus Phakopsora pachyrhizi, considered one of the most severe diseases affecting soybean cultivation. This study aimed to evaluate the use and economic feasibility of a spore collector as a monitoring tool for the causal agent of Asian rust, comparing different fungicide application strategies: preventive applications, scheduled applications, applications based on spore detection, and applications triggered by disease symptoms. The experiment was carried out in the experimental area of the Federal University of Technology – Paraná (UTFPR), Pato Branco campus, during the 2024/2025 growing season, using a randomized block design with four treatments and six replications. Productivity and profitability were evaluated considering fungicide costs and soybean market price. The results showed that the treatment based on spore detection achieved the highest average yield and the greatest net profit, outperforming both the calendar-based and symptom-based applications. It is concluded that the use of the spore collector is an efficient and economically viable tool for the rational management of Asian soybean rust, allowing greater precision in fungicide application and contributing to the sustainability of soybean production.