Due to the importance of Brazil as one of the main world soybean producers and providers, studies to understand the yield reducing factors are of major. Asian soybean rust (ASR) is one of the main reducing factors affecting soybean production. Thus, this study simulated the ASR effects in 24 locations in three Brazilian producing mega-regions, considering different sowing dates, from 15 Sept to 25 Nov for the South and Central mega-regions, and from 05 Oct to 15 Dec for the North mega-region for a historical series of 31 years (1988–2018). Still, we also evaluated the effects of El Niño Southern Oscillation (ENSO) events on disease severity and hence on soybean yield. The approach used in the present study was based on the combination of two models: a disease development model (DDM) for estimating ASR severity, and the process-based crop simulation model (CSM) DSSAT-CROPGRO-Soybean for yield estimation. We compared the yields of affected soybean crops by ASR with disease-free crop yields (ΔY_ASR). On average, the ASR reduced soybean yield between 13 and 33%, with the Central mega-region being the most affected by ASR, followed by North and South mega-regions. ENOS events affected ASR severity, which in turn impacted soybean yields. In the South mega-region, El Niño showed higher impacts on disease than La Niña and Neutral events. In contrast, La Niña and Neutral events impacted more the soybean yield in the North, whereas in the Central mega-region there was no evidence of ENOS impacts on ASR severity and soybean yields.

由于巴西作为世界主要大豆生产商和供应商之一的重要性，了解减产因素的研究具有重要意义。亚洲大豆锈病（ASR）是影响大豆产量的主要减产因素之一。因此，本研究模拟了巴西三个大产区 24 个地点的 ASR 效应，考虑到不同的播种日期，南部和中部大产区为 9 月 15 日至 11 月 25 日，北部大产区为 10 月 5 日至 12 月 15 日。 -区域为 31 年的历史系列（1988-2018）。尽管如此，我们还评估了厄尔尼诺南方涛动 (ENSO) 事件对疾病严重程度以及大豆产量的影响。本研究中使用的方法基于两种模型的组合：用于估计 ASR 严重程度的疾病发展模型 (DDM)，和基于过程的作物模拟模型 (CSM) DSSAT-CROPGRO-Soybean 用于产量估算。我们将 ASR 受影响大豆作物的产量与无病作物产量 (ΔY_ASR）。平均而言，ASR 将大豆产量降低了 13% 至 33%，其中中部大区受 ASR 影响最大，其次是北部和南部大区。ENOS 事件影响了 ASR 的严重程度，进而影响了大豆产量。在南方大区域，厄尔尼诺现象对疾病的影响比拉尼娜和中性事件要大。相比之下，拉尼娜和中性事件对北方大豆产量的影响更大，而在中部大型地区，没有证据表明 ENOS 对 ASR 严重程度和大豆产量产生影响。