Protocol Status
Section Title
Spring Wheat Plant Growth Regulator Use
Trial Information
The purpose of this project is to quantify the impact of using a plant growth regulator on spring wheat.
- The grower will plant a CWRS spring wheat variety.
- The grower will manage their crop as per their normal best management practices.
- The grower will spray a plant growth regulator at the recommended rate at the growth stage timing on 4 strips, alternating with 4 untreated strips.
- Strips should be full length of the field (minimum 1000 ft.) and width to allow for a full “pure” pass with combine header.
- Since 2018, 56 spring wheat PGR trials have been conducted and harvest data collected.
- Two PGRs, Moddus and Manipulator, were utilized in this trial. Manipulator was applied on 47 sites and Moddus on eight sites. An alternative product was also applied to one site.
- Site seeding rates ranged from 90 – 170 lb/ac. All utilized varieties had a lodging rating of good or better.
Results
There was only a statistically significant positive yield response to PGR application at nine (or 16 per cent) of sites. Eight of those sites were sprayed with Manipulator, while one was sprayed with a Kinetin PGR. There was a significantly negative yield response to a PGR application at one site. At the sites with a positive yield response, yields increased on average 3.17 bu/ac. At all sites where a positive significant yield difference was found, the application of a PGR improved returns between $1.43 and $31/ ac, when accounting for product cost only. At sites where no significant yield increases were observed, there was a $17.30/ac loss, when accounting for product cost only.