Objective:               

To examine the phytotoxicity of herbicide treatments on winter wheat

Summary:

This experiment was utilized a randomized complete block design (factorial combination of variety and herbicides). The six winter wheat varieties were paired with two different herbicide treatments: 1) 2x the recommended rate of Beyond herbicide with MSO and 2) Husky Complete herbicide) in three replications. The herbicides were applied on May 4th, 2018. The first and second phytotoxicity ratings were done on May 18th and June 1st, respectively.  Table 1 summarizes detailed management information.

The nursery was planted in the fall of 2017.  Phytotoxicity ratings were conducted to document loss of green pigmentation. During the first and second rating, no observable tissue discoloration was observed. The 2x rate of Beyond herbicide caused no observable plant death on this site among the varieties tested (Table 2).

Table 1. Management information   
Seeding date: 9/26/2017 Harvest date: 8/1/2018
Julian date: 269 Julian date: 213
Seeding rate: 25 plants/ft2 Soil nutrient residual (lb/A): 172-8-178 (Fall, 2017)
Previous crop:  Spring wheat (Egan)  Nutrient fertilizer applied (lb/A):  9-42-60 (Fall)
5-45-0 (Spring)
Tillage:  conventional  Herbicide:  Beyond

Husky complete

 

 Table 2. Effect of herbicide on phytotoxicity and agronomic performance
Treatment  Variety  HD Crop injury  HT LOD YLD1 PRO2 TWT1 TKW FN
Julian 5/18 6/1 in % bu/A % lb/bu g seconds
2X rate Beyond + MSO MTCS1601 157 0 0 35 0 91.6 13 59.4 39.4 444.7
  Clearstone 159 0 0 38.8 0 90.6 11.5 59.3 40.9 445.8
  MTCL1732 159 0 0 31.8 0 80.5 11.3 59 34.5 429.5
  MTCL1834 155 0 0 34.8 0 87.1 12.7 60.8 39 493.9
  MTCL1835 156 0 0 35.3 0 75.6 12.1 60 37.1 400.3
  MTCL1737 160 0 0 31.5 0 80.6 11.3 57.9 31.4 406
Husky Complete MTCS1601 154 0 0 38.3 0 109.5 13.2 59.9 41.4 444.1
  Clearstone 159 0 0 41.6 0 104 11.6 56.1 40.3 434.9
  MTCL1732 158 0 0 31.3 0 93.1 11.3 58.7 37.9 405.2
  MTCL1834 156 0 0 33.8 0 83 12.9 61.1 36.7 481.4
  MTCL1835 157 0 0 36 0 83.3 12.1 61 38.1 393.1
  MTCL1737 159 0 0 32.1 0 65 11.9 57.9 31.6 438
  Mean 158 0 0 35 0 87 12.1 59.3 37.3 435
  CV 1 0 0 8.5 0 11 5.6 2.1 8.2 7
  LSD 1.4 ns ns 3.1 ns 17.6 0.4 1.6 1.9 18
  Pr>F <.0001 ns ns <.0001 ns 0.0299 <.0001 0.001 <.0001 <.0001
YLD: yield, PRO: protein, TWT: test weight, TKW: thousand kernel weight, HT: plant height, LOD: lodging, HD: heading, and FN: falling number           
ns: non-significant at alpha = 0.05           
1 Adjusted to 13% protein           
2 Adjusted to 12% protein