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Yield-Busters Trials Work To Separate Fact From Fiction

Separating fact from fiction and myth from legend is not for the faint of heart. It is, however, for those that love statistics. Chris Holzapfel, research manager with the Indian Head Agricultural Research Foundation (IHARF), is one of those people. It’s good news for farmers that he wants to get to the bottom of whether or not new products on the market really deliver results under field conditions. 2010 marked the launch of IHARF’s Yield-busters trials — a purely agricultural take on the popular Mythbusters TV show.

Holzapfel and the IHARF board of directors asked farmers in the area what products or production practices they’d like to see put to the test. Once a topic is chosen, the trials are then replicated at several other Agri-ARM research stations, because while it might be a playful way to promote field trials, make no mistake that these Yield-busters trials are research trials, not just demonstration. All findings are put through full analysis to determine statistical significance of results.

At IHARF’s recent winter meeting, Holzapfel shared some of the findings from two 2010 Yieldbusters trials: the effect of a micronutrient seed primer on several crops and the use of Headline fungicide on flax.

Disease incidence, in this case pasmo of flax, was not apparent at the recommended spray timing, but visual difference were distinct later in the season. A plant from the treated plot at left, and from untreated at right.


It’s not often that clear-cut results stem from a study in the first year, but Holzapfel says the results of applying Headline EC on flax at the recommended spray timing were staggering. At Indian Head and Canora, flax sprayed with Headline yielded 30 per cent higher than the unsprayed check. Results at Swift Current were less impressive, with no significant yield difference between the sprayed and unsprayed plots.

What Holzapfel also found interesting is that disease ratings prior to spraying (in this case, pasmo) were very low. “There weren’t really any visual signs of disease,” he says. Plots were rated for disease incidence 10 days after spraying. There was a subtle visual difference at that point and it became more pronounced as the season went on.

Flax sprayed with Headline EC matured considerably later than the unsprayed plot, an expected outcome but one that farmers should be aware of. “Flax can usually tolerate fall conditions better than many crops anyway, so (later maturity) is not a huge concern,” Holzapfel says. And given the yield increase of 25 to 30 per cent, the risk of some weathering is likely worth it.

While it is only one year of data, the results are staggering. “Based on these results and reports from growers I can say that if you’re in the black soil zone or an area

*Pricesdo notinclude cost of treating seed –actual costs may vary

with high moisture, a fungicide application on flax will likely be profitable,” Holzapfel. “However, while we are certainly excited, 2010 was an exceptional year with much more precipitation than normal at all locations; we really need to continue these trials and see whether or not these results are repeatable.” Another important observation was that the yield responses occurred in the absence of visual symptoms at the time of application; “It was not until about 10 days after the fungicide was applied that differences in disease incidence started to become noticeable.” The trial did not factor in application cost, however, it budgeted for $17 per acre worth of product. With flax estimated at $14 a bushel, it only takes a slight yield increase to add profit. “We saw a 25 per cent yield increase averaged over all three sites,” Holzapfel says, “but it was as high as 30 per cent at Indian Head.” It doesn’t take much for the benefit to far outweigh the cost.


If only all trials were so definitive. Unfortunately that wasn’t the case when Holzapfel turned his attention to a micronutrient seed primer trial. The objective was to evaluate seed-applied micronutrient primers on crop emergence, days to maturity and yield of wheat, canola, pea and lentil (OMEX brand products were used with Zn Primer used on the wheat and canola and Pulse Primer on pea and lentils).

In setting up this particular trial, Holzapfel worked with Western Ag Labs to first determine if zinc could be at all limiting during the growing season (zinc is one of the components of the Omex product). The lab’s modelling software determined that zinc could become limiting during the growing season, based on soil tests and crop use averages (see Table 1).

For this trial, Holzapfel evaluated the micronutrient seed primers at four sites: Indian Head, Canora, Scott and Swift Current, Sask. There was no significant impact on emergence The untreated check (on left) showed significantly higher disease incidence than the treated plot (at right). Maturity in treated plots was delayed.

Micronutrient seed dressing had no significant impact on crop emergence. Three out of four sites did see reduced wheat emergence in treated plots, but researchers hesitate to attribute that to the seed dressing at this time.

rates, except in the case of wheat, where in three out of four sites it was actually negatively impacted. That said, Holzapfel says that plant-stand numbers were still high enough to be considered adequate. “At Indian Head we went from 320 plants per square metre to 275 in the treated plot. That’s still a good plant population that should not have any impact on grain yield,” he says. He also adds that they are not jumping to conclusions to say that the primer caused the observed reduction in wheat populations as variability was high and this is only the first year of the study; this trial will be continued in 2011.

Days to maturity was also unaffected by the Primer, as was yield. “Statistically there were no significant yield differences between treated and untreated plot yields for any of the crops,” Holzapfel says. “But it was also a tough growing season. We were cool and wet, and it is possible that adverse conditions limited yields to extent where could not detect subtle impacts the primers could have had on yield.” This is only one year; a return to more average conditions to test under in 2011 (we hope) should add more insight into results.

Holzapfel says that he was somewhat surprised to see the cost range of the product (per acre) based on crop type. For canola, it’s literally less than a dollar an acre ($0.56/ac.), however because the product would be applied to already treated canola, it would mean added labour and exposure to treated seed if application is done on farm. Peas were the most expensive to treat at $8 an acre (based on a 195 lb./ac. seeding rate); lentil ($4.10) and wheat ($4.95) fell somewhere in the middle. These costs are for product only and do not include the cost of treating.

If you’ve got an idea for the Yield-busters trials, or would like more information the 2010 trials, email Chris Holzapfel at cholzapfel. [email protected] or call the IHARF office at 306-695- 4200.


Contactherat [email protected]


6.5 50 $0.53 $4.10






Rate lb/ac Cost $/ac

120 $4.92

195 $8.00

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