Objective:       

To evaluate winter wheat height response to the application of different commercial plant growth regulators.

Materials and Methods:

Lodging is a recurring problem in winter wheat production, and is largely a function of plant height.  This study was designed to determine the effect of plant growth regulators on reducing crop height, and in turn, percent lodging. 

Results:

The study was established as a randomized complete block with three replications.  Yellowstone winter wheat was planted at 80 lb/A in 7 inch rows on September 29, 2014.  Treatments were applied the following spring. Palisade and Cerone were applied at the two node and flag leaf stage of growth, respectively, either alone or as sequential applications. Palisade was applied at 10.5 oz/A and 14.4 oz/A, while Cerone was applied at 0.5 pt/A and 1.0 pt/A.

The application of plant growth regulators had a significant effect on lodging yet had no significant effect on height. Lodging averaged 12.2% and ranged from 0.0% to 58.0 percent. All treatments afforded a significant reduction in lodging compared to the control.  However, there were no significant differences among PGR treatments.

Summary:       

Plant growth regulators were effective at reducing lodging.  However, the degree of lodging did not impact winter wheat yields.

 

Table 1. Materials and Methods - Effect of PGRs on Winter Wheat   
Seeding Date: 9/29/2014 Harvest Date: 7/30/2015
Julian Date: 272 Julian Date: 211
Seeding Rate: 80 lbs/A Soil Type: Creston SiL
Previous Crop: Canola Soil Test: 29-10-158
Tillage: Conventional Fertilizer: 9-40-10, 0-0-62,130-0-0 TD
Irrigation: None Herbicide: Huskie Complete 13.7 oz/A

 

 

Table 2. Agronomic data from the effects of PGRs on winter wheat yield and quality          
      HD HT LOD YLD¹ PRO² TWT¹ TKW¹ FN
Treatment Rate Julian in % bu/A % lb/bu g sec
Check                153 40.7 58.0 143.5 11.5 60.3 39.3 409.4
Cerone 0.5 pt/A 153 39.7 0.0 156.6 11.3 61.1 38.6 428.5
Cerone 1.0 pt/A 152 38.7 0.0 142.4 11.2 61.3 39.1 432.2
Palisade 10.5 fl oz/A 153 40.3 20.7 143.7 11.1 60.7 39.9 421.9
Palisade 14.4 floz/A 153 41.0 0.0 152.8 11.2 61.4 38.8 425.0
Palisade 10.5 fl oz/A 152 40.3 6.7 152.2 11.7 60.9 37.6 431.3
+ Cerone 0.5 pt/A                
Palisade 14.4 fl oz/A 152 39.3 0.0 143.9 11.3 61.0 38.9 430.7
+ Cerone 1 pt/A                
Mean   153 40.0 12.2 147.9 11.3 61.0 38.9 425.6
CV   0.4 3.2 167.9 4.9 5.8 1.0 3.2 4.8
LSD   ns ns 36.4 ns ns ns ns ns
Pr>F   0.6596 0.3697 0.0359 0.1606 0.9449 0.3849 0.4958 0.8246
HD: heading date, HT: height, LOD: lodging, YLD: yield, PRO: protein, TWT: test weight, TKW: thousand kernel weight, FN: falling number, ns: nonsignificant          

¹adjusted to 13% moisture

²adjusted to 12% moisture