The Efficacy of Ethaboxam as a Soybean Seed Treatment Toward Phytophthora, Phytopythium, and Pythium in Ohio

Abstract

Phytophthora, Phytopythium, and Pythium species that cause early-season seed decay and pre-emergence and post-emergence damping off of soybean are most commonly managed with seed treatments. The phenylamide fungicides metalaxyl and mefenoxam, and ethaboxam are effective toward some but not all species. The primary objective of this study was to evaluate the efficacy of ethaboxam in fungicide mixtures and compare those with other fungicides as seed treatments to protect soybean against Pythium, Phytopythium, and Phytophthora species in both high-disease field environments and laboratory seed plate assays. The second objective was to evaluate these seed treatment mixtures on cultivars that have varying levels and combinations of resistance to these soilborne pathogens. Five of eight environments received adequate precipitation in the 14 days after planting for high levels of seedling disease development and treatment evaluations. Three environments had significantly greater stands, and three had significantly greater yield when ethaboxam was used in the seed treatment mixture compared with treatments containing metalaxyl or mefenoxam alone. Three fungicide formulations significantly reduced disease severity compared with nontreated in the seed plate assay for 17 species. However, the combination of ethaboxam plus metalaxyl in a mixture was more effective than either fungicide alone against some Pythium and Phytopythium species. Overall, our results indicate that the addition of ethaboxam to a fungicide seed treatment is effective in reducing seed rot caused by these pathogens commonly isolated from soybean in Ohio but that these effects can be masked when cultivars with resistance are planted.

Agronomic and efficacy evaluations of oxathiapiprolin as a soybean seed treatment

“…or Pythium sp. (Scott et al, 2020). Plant stands were improved by seed treatment combinations of different fungicides (Gaspar et al, 2014;Hegstad & O'Bryan, 2017).…”

“…Fungicide seed treatments have been shown to provide protection during the vulnerable time period after planting, especially under conditions likely to result in disease development (Dorrance and McClure, 2001;Ellis et al, 2008;Munkvold, 2009;Urrea et al, 2013;Munkvold et al, 2014;Scott et al, 2020). Fungicide-only seed treatments have been found to increase plant stand and final yield performance in locations with moderate to high P. sojae pressure (Bradley, 2008;Dorrance et al, 2009;Dorrance, 2018).…”

“…The integration of multiple disease management approaches including use of cultivars with Rps genes in combination with fungicide seed treatment is strongly recommended when there is a high risk for disease development (Dorrance, 2018). Fungicide seed treatments have been shown to provide protection during the vulnerable time period after planting, especially under conditions likely to result in disease development (Dorrance & McClure, 2001; Ellis et al., 2008; Munkvold, 2009; Munkvold et al., 2014; Scott et al., 2020; Urrea et al., 2013). Fungicide‐only seed treatments have been found to increase plant stand and final yield performance in locations with moderate to high P. sojae pressure (Bradley, 2008; Dorrance, 2018; Dorrance et al., 2009).…”

Plant extract as a strategy for the management of seed pathogens: a critical review

“…Many studies have been conducted to investigate the use of synthetic chemical products for disease management in seeds (Sartori et al, 2020;Scott et al, 2020;Shcherbakova et al, 2021). Nevertheless, studies on plant extracts for disease management are still incipient and further investigations are needed to provide alternative tools to synthetic products that are ecologically viable.…”

Two‐Step Continuous‐Flow Synthesis of Fungicide Metalaxyl through Catalytic C−N Bond‐Formation Processes

“…To reduce the environmental impact associated with pesticide use, harmful processes associated with their manufacture must be minimized and efficient technologies in this field are in high demand. A series of acyl alanine-type pesticides such as metalaxyl (1), benalaxyl (2), furalaxyl (3), and ofurace (4) are common, commercially available phenylamide fungicides (PAFs; Scheme 1(a)). [1] PAFs affect mitosis and cell division in fungi, and are widely used on a preventive basis for plant diseases.…”