Fungicides Boost Yield, Speed Maturity

Crops that received fungicide ripened faster than those without, which is contrary to what is supposed to happen

Brett Casavant farms near Tisdale, Sask., and every year he grapples with the question of whether or not fungicides offer a return on the cost. To try and pin down an anwer, he’s been conducting his own on-farm fungicide trials for the past three years.

Casavant has been comparing the yield data from around forty locations in his wheat fields that were all treated with fungicides, against an untreated test strip in each one. Unfortunately things didn’t go too well with the data collection last fall largely because of the rush to finish harvest in the narrow window that the rains allowed. A software malfunction on one of the combines he was using to do yield mapping didn’t help matters either.

“I haven’t been able to put together a proper analysis on the data,” says Casavant, who emphasizes that any results he has seen from this informal study may not be applicable to other areas, because there are so many variables, such as soil conditions, weather and varieties grown. But he does believe that, based on his three years of findings, the use of a foliar fungicide on all crops has bumped or maintained yield enough to outweigh the additional cost involved.

“I have had some pretty phenomenal returns. I think we averaged an additional return of seven bushels per acre two years ago across our whole farm (because of fungicide use). When we were getting $6 a bushel for our wheat that was $45 an acre for an investment of $10. that’s a pretty good return on investment,” says Casavant.


But Casavant has also been doing a few things differently than most other producers. For example on his wheat crops, rather than applying the fungicide at the leaf stage as recommended, he has been applying it later after the heads have started to emerge. This he believes may have helped improve the yield.

He has also found that crops that received fungicide ripened faster than those without, which is contrary to what is supposed to happen.

“The thought is that disease

makes the crop ripen quicker and kills it earlier and that when you put fungicide on it, it lets the crop reach its full potential. In theory, that should take longer to ripen,” says Casavant. “According to what all the chemical representatives and agrologists tell me, fungicide should make it take longer than it normally would to ripen. But

what we found in our fields was that all our untreated test strips stood out really strong this year because they were not ready to harvest when the rest of the field was. There was quite a noticeable maturity difference where we had kept the plant more healthy with fungicide and it ripened quicker.”

Casavant has based some of his trial on data that came from some previous work done in the late 1990s by the Northeast Agricultural Research Foundation (NARF), which produced similar results to those he has seen, particularly when the fungicides were applied later.

His work has prompted others to also start some independent fungicide trials. Local agronomy consultants, Soil Tech Services set up untreated test strips in barley, wheat, pea and oat crops of about twenty local producers. Although still compiling the results one thing they did observe in many of the plots was a shorter time to maturity, as Casavant had.

“It seemed that a lot of those crops were a little further along where they were sprayed, but then you hear the odd guy who says, ‘Well I think it added four or five more days to maturity, so we will be looking at that a bit more closely,’” says agronomist Damon Brandt of Soil Tech, who will do more trials over the next few years and also compare late and early fungicide applications to see what effect timing has on yield and maturity.

Wheat prices are far from $6 a bushel going into this spring and Casavant admits that, although he pencils in the cost of fungicides every year, that decision comes down to economics in the end.

“We are always going for high value and high yield, but maybe this year there is going to be another consideration because wheat right now is a terrible price. We need more bushels to make it pay,” he says. “If the crop doesn’t look like it has that much of a chance, if it’s dry or something, we might just keep as much money in our pockets as we can.”

It’s not likely, however, that he will be tempted to cut out the fungicide as long as things don’t look too bleak. “It’s hard to make broad statements but I do firmly believe that fungicide has helped us a lot,” says Casavant, “but there are so many variables out there that everyone has to consider for themselves whether they are going to be worth it or not.”

Angela Lovell is a freelance writer based at Manitou, Man.

About the author


Angela Lovell

Angela Lovell is a freelance writer based in Manitou, Manitoba. Visit her website at or follow her on Twitter @angelalovell10.



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