Foliar fungicides can account for a large portion of the yield gap in winter wheat (Triticum aestivum L.); however, their impacts on yield have been inconsistent in rainfed environments. We compiled a database of replicated field experiments and producer-reported fungicide and yield data from commercial fields to quantify the effects of fungicide application on winter wheat yield and yield stability. The database of field experiments (i.e., canopy level) included 56 non-inoculated environments spanning 12 growing seasons in eight Kansas locations, and was restricted to field experiments with direct comparisons between a foliar fungicide between Zadoks 40–55 and a side-by-side untreated control, resulting in 393 mean yield comparisons resulting from 3226 yield observations. The producer survey included genotype and fungicide management data from 654 commercial Kansas wheat fields cultivated across three growing seasons. Grain yield and weather conditions in the experimental and producer-reported database were similar, with seasonal precipitation ranging from ˜150 to 1035 mm and average grain yield of ˜3900 kg ha⁻¹ with a ˜7000 kg ha⁻¹ range. Foliar fungicide application resulted in 7.8 % average yield gain in the canopy-level data, ranging from −27 % to +97 %. Yield differences due to fungicide were strongly related to precipitation and to the ratio of precipitation and reference evapotranspiration (WS:WD) during the spring in the experimental data. Grain yield responsiveness to fungicide associated with the responsiveness of green canopy cover, kernel weight, biomass, and harvest index. Analysis of covariance suggested that grain yield usually decreased with increases in disease susceptibility in the absence of foliar fungicides; however, yield-disease relationships were either neutral or positive in the presence of fungicides. Average yield gain for resistant varieties was ˜166 kg ha⁻¹ (5.6 %), which was lower than for intermediate (˜199 kg ha⁻¹; 6.9 %) or susceptible genotypes (˜598 kg ha⁻¹; 16.9 %). Foliar fungicides increased yield stability across genotypes at the canopy level and at the commercial field level. In the commercial-field level data, 53 % of the fields received foliar fungicide, with higher frequency in growing seasons with greater WS:WD (which were also higher yielding). The use of foliar fungicides was associated with improved yields and interacted with genotype’s resistance level to stripe rust and with growing seasons’ WS:WD. This work quantified and explained the yield benefits of foliar fungicide, and characterized its dependency on genotype-specific disease resistance and environmental conditions both at the canopy- and commercial field-levels.

叶面杀菌剂可以解释冬小麦（Triticum aestivum ）产量差距的很大一部分L.); 然而，在雨养环境中，它们对产量的影响并不一致。我们编制了一个包含重复田间试验和生产商报告的来自商业田地的杀菌剂和产量数据的数据库，以量化杀菌剂应用对冬小麦产量和产量稳定性的影响。田间试验数据库（即冠层水平）包括堪萨斯州 8 个地点 12 个生长季节的 56 个未接种环境，仅限于田间试验，直接比较 Zadoks 40-55 和并排的叶面杀菌剂侧未处理的对照，从 3226 个产量观察结果产生 393 个平均产量比较。生产者调查包括来自在三个生长季节种植的 654 个商业堪萨斯麦田的基因型和杀菌剂管理数据。^-1具有～7000 kg ha ^-1范围。在冠层水平数据中，叶面杀菌剂施用导致 7.8% 的平均产量增加，范围从 -27% 到 +97%。杀菌剂导致的产量差异与实验数据中春季的降水量以及降水量与参考蒸散量 (WS:WD) 的比率密切相关。谷物产量对杀真菌剂的响应与绿色冠层、谷粒重量、生物量和收获指数的响应相关。协方差分析表明，在没有叶面杀菌剂的情况下，谷物产量通常随着病害易感性的增加而下降；然而，在存在杀菌剂的情况下，产量与病害的关系要么是中性的，要么是积极的。抗性品种的平均增产为~166 kg ha ^-1(5.6 %)，低于中间基因型 (~ 199 kg ha ^-1 ; 6.9 %) 或易感基因型 (~598 kg ha ^-1; 16.9%)。叶面杀菌剂在冠层水平和商业田间水平上提高了基因型的产量稳定性。在商业田地水平数据中，53% 的田地接受了叶面杀菌剂，在 WS:WD 较大的生长季节频率较高（产量也较高）。叶面杀菌剂的使用与产量的提高有关，并与基因型对条锈病的抗性水平和生长季节的 WS:WD 相互作用。这项工作量化并解释了叶面杀菌剂的产量优势，并表征了其在冠层和商业田间水平对基因型特异性抗病性和环境条件的依赖性。