According to\u00a0Anti-rust Consortium<\/a>The 2025\/2026 soybean crop has 144 reported cases of Asian soybean rust, one of the most severe diseases affecting soybean crops: 88 cases in Paran\u00e1, 44 in Mato Grosso do Sul, 5 in Rio Grande do Sul, 4 in S\u00e3o Paulo, 2 in Santa Catarina, and 1 in Minas Gerais. Comparing this to the same period last year, Paran\u00e1 had registered 41 cases at the beginning of January. Therefore, Paran\u00e1 has double the number of occurrences compared to the previous crop. "The increase in the number of reports does not indicate a loss of control of the disease, but rather that rust has been identified in the region and needs to be managed properly. It is a sign that spores are circulating and that producers need to use fungicides effectively to manage the rust," emphasizes researcher Cl\u00e1udia Godoy, from Embrapa Soja.<\/p>\n According to the researcher, the higher occurrence of reports of Asian soybean rust in southern Brazil is related to the greater survival of volunteer soybean plants during the off-season, the planting window in the region, and disease monitoring. The researcher states that the wetter climate during the winter in the South favors the survival of volunteer soybeans\u2014plants that sprout spontaneously after harvest\u2014and, consequently, of the fungus that causes rust. \u201cWith rainfall in the winter, there is greater survival of volunteer soybeans, in which the fungus ends up surviving,\u201d she explains. \u201cIn the Cerrado, where the winter is drier, this survival is lower,\u201d says the researcher.<\/p>\n Photo: Fernando Dias\/Ascom Seapi<\/p>\n<\/div>\n The sanitary break, a 90-day period during which soybean planting is prohibited, mandates the elimination of soybean plants. \u201cEven so, there is a significant presence of these plants among other crops in the Southern region, which contributes to the maintenance of the disease,\u201d she says. Another factor pointed out by the researcher is the planting window. \u201cStates like Paran\u00e1 begin planting as early as September 1st, as do regions of Paraguay. The earlier the planting, the sooner rust begins to appear, especially when there is proximity to sources of inoculum,\u201d states Cl\u00e1udia.<\/p>\n Furthermore, the high number of reports in the South is also linked to the registration methodology. The data from the Antiferrugem Consortium are counted by municipality, and Paran\u00e1, for example, has a larger number of municipalities compared to other states. \u201cThe registrations are voluntary and depend on the work of technicians and agronomists in the field. And regions with a strong presence of cooperatives, as is the case in Paran\u00e1, end up presenting a higher number of notifications,\u201d explains Cl\u00e1udia.<\/p>\n In the Brazilian Midwest, on the other hand, the harvest is approaching and rust tends to have less impact. \u201cProducers are managing to \u2018escape\u2019 the disease more effectively. However, in this region, other diseases, such as target spot, have greater economic relevance,\u201d Claudia points out.<\/p>\n With the increasing resistance of the Asian soybean rust fungus to fungicides, there is a need to use multi-site products in combination. These fungicides attack the fungus at multiple points in its metabolism simultaneously, therefore, the risk of the fungus developing resistance to them is lower. "This strategy is fundamental to increasing the efficiency of control and prolonging the useful life of available fungicides," he states.<\/p>\n Producers can download the Antiferrugem Consortium app at Google Play and Apple Store<\/em>\u00a0and monitor the data from the Antiferrugem Consortium. The effectiveness of fungicides available on the market can be consulted in the application \u201cClassification of the effectiveness of chemical and biological fungicides: soybean module\u201d on the network's website.\u00a0tropical plant health<\/a>\u00a0(RFT), with information based on cooperative trials of four growing seasons. Technical circulars with detailed trials for Asian soybean rust are available at\u00a0RFT website.<\/a><\/p>\n![](\"https:\/\/i0.wp.com\/opresenterural.com.br\/wp-content\/uploads\/2025\/09\/Sinais-quando-o-fungo-Phakopsora-pachyrhizi-ataca-a-planta-.jpg?resize=300%2C169&ssl=1\")
<\/p>\nGuidelines for producers<\/h4>\n