Dec 15, 2022

Alert System Identifies Soybean Rust in Southern Brazil

Author: Michael Cordonnier/Soybean & Corn Advisor, Inc.

Asian soybean rust, (Phakopsora pachyrhizi) is the most destructive fungal disease afflicting Brazilian soybeans, so Brazilian producers are on constant alert for the presence of the disease in their area. The best indication of a potential outbreak of the disease is the presence of rust spores in an area.

The first cases of soybean rust in commercial soybean fields were confirmed over the last two weeks in the state of Parana. The state of Parana has installed more than 200 spore-collecting devices strategically located throughout the state to monitor the presence of rust spores. The system has identified soybean rust spores in 17 locations primarily in western Parana.

The first spores were detected on October 28. The director of the collection program indicated that this is earlier than last year and he attributes it to a more humid climate during the winter period. Frequent rains and higher levels of humidity favors the development of rust as the soybean plants begin flowering.

Soybean rust infections in Brazil are monitored by the Rust Alert System (Rede Alert Ferrugem) of the Antirust Consortium (Consorcio Antiferrugem) which is run by Embrapa. Consorcio Antiferrugem is the central gathering mechanism monitoring the disease in all the Brazilian states

The goal of the system is to monitor the presence of rust spores and alert producers when chemical controls should be applied. There is no cure for soybean rust, so it is important that timely preventative measures be taken the moment that the disease arrives in an area.

The alert system also helps farmers save time and money by not applying control measures if the disease is not present in their area. It can also help farmers by not letting the disease get a head start resulting in lower yields.