Meta-analysis of yield response of foliar fungicide-treated hybrid corn in the United States and Ontario, Canada

Abstract

Background Foliar fungicide applications to corn ( Zea mays L.) occur at one or more application timings ranging from early vegetative growth stages to mid-reproductive stages. Previous studies indicated that fungicide applications are profitable under high disease pressure when applied during the tasseling to silking growth stages. Few comprehensive studies in corn have examined the impact of fungicide applications at an early vegetative growth stage (V6) compared to late application timings (VT) for yield response and return on fungicide investment (ROI) across multiple locations. Objective Compare yield response of fungicide application timing across multiple fungicide classes and calculate the probability of positive ROI. Methods Data were collected specifically for this analysis using a uniform protocol conducted in 13 states in the United States and one province in Canada from 2014–2015. Data were subjected to a primary mixed-model analysis of variance. Subsequent univariate meta-analyses, with and without moderator variables, were performed using standard meta-analytic procedures. Follow-up power and prediction analyses were performed to aid interpretation and development of management recommendations. Results Fungicide application resulted in a range of yield responses from -2,683.0 to 3,230.9 kg/ha relative to the non-treated control, with 68.2% of these responses being positive. Evidence suggests that all three moderator variables tested (application timing, fungicide class, and disease base level), had some effect (α = 0.05) on the absolute difference in yield between fungicide treated and non-treated plots ( ). Application timing influenced , with V6 + VT and the VT application timings resulting in greater yield responses than the V6 application timing alone. Fungicide formulations that combined demethylation inhibitor and quinone outside inhibitor fungicides significantly increased yield response. Conclusion Foliar fungicide applications can increase corn grain yield. To ensure the likelihood of a positive ROI, farmers should focus on applications at VT and use fungicides that include a mix of demethylation inhibitor and quinone outside inhibitor active ingredients.

Effectiveness of fungicides with different modes of action against net blotch disease of two-rowed spring barley

“…Results from a complex study that tested over ten fungicide formulations on maize crops at locations from Canada and United States, indicated that fungicide class had some effect on yield of maize. Formulations based on DMI+QoI contributed significantly to the maize yield (Wise et al, 2019). Strobilurins have been associated with enhancing physiological effects on plants.…”

Fungicide Resistance in Powdery Mildew Fungi

“…A large amount of money is invested annually in fungicide spray programs, and profits are reduced when resistance arises. A recent publication has described, for example, general costs of 45.14 USD/ha for ground application and 51.80 USD/ha for aerial application in corn in the U.S. [ 170 ] or loss of GBP 170 m/year for UK growers to control the cereal eyespot ( Oculimacula yallundae ) during the 1980s [ 171 ]. Moreover, the most common powdery mildew fungi are high-risk pathogens, and as documented in this review, important cases of practical resistance have been reported in several parts of the world, such as Africa, Australia, Brazil, Canada, China, Europe (Austria, Belgium, Czech Republic, Denmark, France, Germany, Greece, Hungary, Italy, Portugal, Scandinavia, Spain and the Netherlands), Egypt, India, Iran, Japan, New Zealand, UK, and the US (California, Georgia, Michigan, New Jersey, New York, North Carolina, Ohio, South Carolina and Virginia).…”

Trends in Agricultural Triazole Fungicide Use in the United States, 1992–2016 and Possible Implications for Antifungal-Resistant Fungi in Human Disease

“…Fungicides have been widely used for centuries to treat plant infections, prevent crop loss, and increase agricultural yield; fungicides are also used to preserve wood and other materials (Morton and Staub 2008;Russell 2005;ECDC 2013;U.S. EPA 2015;Wise et al 2019;Wise and Mueller 2011). Data on global triazole usage are limited, and the United Nations' Food and Agriculture Organization provides data on combined triazole and diazole use, making it difficult to determine the amount of triazole use alone (FAOSTAT 2019).…”