Ontario Corn Hybrid DON Screening Trials Now Available


The inaugural 2023 Ontario corn hybrid DON screening trial report is available on GoCorn.net at http://www.gocorn.net/OCC_DON_Report_2023_Final_20230212.pdf.

Ontario corn hybrid DON screening trials were initiated by the Ontario Corn Committee in 2019 following high DON levels in the 2018 corn crop. Hybrid susceptibility is one of the greatest factors influencing Gibberella Ear Rot (Figure 1) and DON accumulation in corn (second only to weather), and the greatest factor that can be controlled by agronomic practices (Hooker and Schaafsma, 2005). Ontario growers can reduce DON risks through hybrid selection and management and have asked for DON hybrid testing for many years. 

Figure 1. Gibberella Ear Rot.


Starting in 2019, the Ontario Corn Committee (OCC) refined protocols for testing hybrid sensitivity to DON accumulation with confidence based on an assessed risk. This inaugural report provides a risk assessment of hybrids entered in the 2023 trials, along with a multi‐year assessment on the same hybrids if data were available.

Hybrids were entered voluntarily by seed companies and all hybrids are compared against a “check” hybrid known to be highly sensitive to Gibberella Ear Rot and DON accumulation. Hybrid results are displayed as an index value relative to this high check hybrid (Table 1). This data serves as a relative risk assessment of hybrids that can be used with other information sources (e.g., seed company information, field trial results, etc.) to improve hybrid decisions. See the report for full details.

Table 1. Relative DON risk assessment indices by hybrid relative to susceptible check from 2020‐2023. Hybrids are
sorted by CHU rating. Always use one‐year data with caution. The colour scheme highlights hybrid effects within
column. An index=100 means DON equal to the susceptible check.


A sincere thank you to Dr. Dave Hooker, University of Guelph and Albert Tenuta, OMAFRA for leading this project and for the support from corn hybrid seed companies for voluntarily participating in this trial. Thanks to those who have provided financial support to allow these trials to be conducted (OMAFRA, Canadian Agricultural Partnership and Sustainable Canadian Agricultural Partnership, Grain Farmers of Ontario, Greenfield Ethanol, Ingredion, Ontario Pork, Suncor and participating seed companies including Brevant, Country Farm Seeds, CROPLAN, Dekalb, Maizex Seeds, NK Brand, Pioneer, Pride Seeds and Saatbau)


About the Ontario Corn Committee

The Ontario Corn Committee is made up of representatives from Agriculture and Agri-Food Canada; Ontario Ministry of Agriculture, Food and Rural Affairs; University of Guelph;  Ontario Soil and Crop Improvement Association; Grain Farmers of Ontario; Ontario Agri Business Association; Ontario Certified Crop Advisors and Seeds Canada. Hybrid tests are conducted each year by the following cooperating agencies: University of Guelph, Ridgetown Campus; University of Guelph Plant Agriculture Department; University of Guelph, Winchester Research Station; Kent Ag Research Inc.; and Agriculture and Agri-Food Canada (Ottawa).