The Prairie Giants Crop Report

Field observations at your fingertips

June 15, 2021

Taylor Kurtenbach

Welcome to the Prairie Giants Crop Report! We’ll be breaking down our observations from the field into a concise, semi-regular report.

Plant Growth Regulators (PGRs) in Cereals
Cereals are looking good, and sprayers are rolling! On average, 50% of wheat, 25% of barley and 20% of oats are sprayed. Cereal staging ranges, but on average wheat is around 5 leaf. The wheat seemed slow out of the ground, focussing on below ground growth/rooting down in dry conditions, but now with the rain and sunshine it has really jumped. With the recent rains we have also started getting questions about plant growth regulators in cereals!

Plant growth regulators (PGRs) are synthetic compounds that mimic naturally occurring hormones to alter plant growth and development[1]. In cereal crops, they are used to shorten plants and thicken stems to reduce lodging.  

Manipulator and Moddus (new for 2021!) are two different plant growth regulators. Both products inhibit gibberellin production, the hormone responsible for shoot elongation, resulting in shorter, thicker stems. Moddus (active ingredient trinexapac-ethyl) works quicker, whereas Manipulator (active ingredient chlormequat-chloride) remains in the plant longer. They are both registered in wheat, barley and oats, but effectiveness varies. Manipulator is most responsive in wheat[2;] Moddus is most responsive in barley and oats. 
Active IngredientChlormequat-chloride
Registered CropsWheat*, barley, oatsWheat, barley*, oats*
Application Rates
(single app.)
Wheat: 14 – 20 acres/jug
Barley: 11 acres/jug
Oats: 14 acres/jug
Wheat: 30 acres/jug
Barley: 24 acres/jug
Oats: 30 acres/jug
Application TimingBBCH 30 – 39BBCH 30 – 39

*most responsive


There are different application rates registered depending on the crop and application timing. Both products can be applied as a single or split application, as well as having the flexibility to be tank mixed with herbicide and fungicide. When applying with herbicides, precaution should be taken to avoid crop injury. Talk to us to figure out the best application rate, timing and tank mix partners that will work for your farm! 

So, when should you use a PGR?! In conditions of high moisture and high fertility where lodging is a concern. They should not be applied in stressful conditions such as drought, water-logged soils and cool temperatures. Applying in these conditions can lead to crop injury. PGR’s goal is to reduce lodging, aid in harvestability and protect grain quality. It does not always result in a direct yield gain. Interested in using a PGR? Talk to the crew at Prairie Giants!  

[1] Strydhorst, S. 2014. "Plant Growth Regulators: What Agronomists Need to Know." University of Manitoba. [Online] Available:
[2] Canterra Seeds. 2018. "Everything Cereal Growers Need to Know About Plant Growth Regulators." Canterra Seeds. [Online] Available: 

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