From an environmental standpoint, Ontario experienced a perfect storm in 2018 that produced an epidemic of gibberella ear rot in corn and resulting unprecedented DON levels.
Ontario Ministry of Agriculture, Food and Rural Affairs field crop plant pathologist Albert Tenuta compares the conditions that created the classic silk channel infection in corn hybrids to what farmers also witnessed in 2006 — rain for four and five days during silking, as well as high humidity and heavy dews that kept cornfields wet, creating ideal conditions for the fungi.
Like growers, Tenuta is hoping not to see a repeat of the DON epidemic, and has three key management recommendations for 2019. He shares these tips on this episode of RealAgriculture Corn School filmed last week at the Southwest Agricultural Conference at Ridgetown, Ontario.
For starters, growers need to consider ear rot tolerance when selecting hybrids, says Tenuta. He acknowledges that yield is always king when making seed choices, but growers should check with their seed provider and ask for tolerance ratings for their hybrids. He notes that no hybrids are 100 per cent resistant, however, there are those that are more highly susceptible and planting more hybrids is preferable to reducing the number of hybrids planted on your farm — don’t put all your eggs in one basket. (Story continues after video.)
Tenuta also says it’s important for growers to manage western bean cutworm (WBC) and the wounds and openings the pest can create that allow gibberella to infect the plant.
A third consideration is insecticide and fungicide application timing. Targeting an insecticide application at the green silk/silking stage is the best way to prevent WBC ear damage. Also going in with a fungicide application during this stage is a good DON management strategy. Tenuta adds it’s important for growers to remember that fungicide applied at tassel timing is effective for maintaining leaf health and driving yield but it may miss the critical stage for gibberella development inthe classic silk channel infection, like we saw this year.
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