PROJECT RESULTS

Application Method of Copper Yield Trials on Spring Wheat

Applicant: 

Kathi Furniss
Pembina Valley Conservation District
Manitou, Manitoba  R0G 1G0  Canada

Table of Contents:

• Background and Objective
• Procedure and Project Activities
• Results and Discussion
• Conclusions

ARDI Project:

#99-290

Project Status:

Completed April, 2002

Background and Objective:

Copper is one of the micronutrients essential for plant growth. In Manitoba, crop response to applied copper is variable. The most responsive crop tends to be wheat, which under deficient situations suffer reduced yield and grain quality. Soils most likely to be deficient in copper are peat soils or sandy textured soils that are low in organic matter with high pH. Occasionally responses are observed on other soils. Soil analysis is suggested to assist in identifying responsive soils.

Guidelines for applying copper are often not clear. A number of application methods and products are presented to growers. The suggested method through Manitoba Agriculture and Food is broadcast and incorporated copper sulphate at 5-10 lb Cu/ac or 1-2 lb Cu/ac as EDTA copper chelate (Manitoba Agriculture and Food, 2001).

The following study was conducted to determine the optimum method of copper application to spring wheat. The various treatments will be evaluated on their economic performance.

Procedure and Project Activities:

Identify Cooperators and Fields

Potential field sites for the study were identified through advance soil testing of many producer fields in the Pilot Mound area. MidWest Laboratories in Calgary determined soil with 0.8 ppm (DTPA extractable) were low in copper, requiring 2.5 lb Cu/ac. The fields were located in the Pilot Mound area and the cooperating producers were Landon Cavers and John Smith. Soils were predominately Carroll clay loam.

Experimental Design

On-farm testing principles employing a RCB design were used in establishing this experiment. Individual treatment plots were the full length of the field and width to accommodate the producers’ field equipment. The plot dimension at the Smith field was 44’ wide by 1788’ long and at the Cavers field was 39’ wide by 2365’ long. The seven treatments were randomized and replicated four times, for a total of 28 plots per field. Headlands around the outside of the field were seeded with three passes of the seeder. Plots were located inside the headlands to avoid field edge effect.

Similar experimental design was used in 2000 and 2001 at both sites for a total of four experiments.

Treatments

Treatments consisted of copper product and application method combinations. Treatments are listed below:

1. Check – control with no copper added.
2. Liquid copper (Stoller 5%) at 2 l/ac to supply 0.26 lb Cu/ac was applied foliarly at the 2-4 leaf stage with a Rogator 854.
3. Liquid copper (Stoller 5%) at 2 l/ac to supply 0.26 lb Cu/ac was applied foliarly at the 6-leaf to flagleaf stage with a Rogator 854.
4. Copper chelate (Ruff’nTuff 5% G) at 6 lb/ac to supply 0.3 lb Cu/ac was applied with the seed in a blend with starter phosphate fertilizer.
5. Liquid copper chelate (Nortrace Copper 7.5% EDTA ) at 2 l/ac to supply 0.41 lb Cu/ac was pre-plant broadcast with a Rogator 854 incorporated to a depth of 2-3 inches.
6. Dry copper chelate (Ruff’nTuff 5% G) at 6 lb/ac to supply 0.3 lb Cu/ac was pre-plant broadcast with a PT Valmar 500 applicator incorporated to a depth of 2-3 inches.
7. Granular copper sulphate (20% Cu) at 10 lb/ac to supply 2.5 lb Cu/ac was pre-plant broadcast with a PT Valmar 500 applicator and incorporated to a depth of 2-3 inches.

The rates were based on the MidWest Laboratory recommendation of 2.5 lb Cu/ac. Many of the chelated and foliar products have reduced rates due to expectations of increased efficiency.

Standard crop production practices were followed for all other aspects of CWRS wheat production.

Production practices and operation timing:

Observations

Copper status of soil was determined prior to application and after harvest in each plot. Eight cores were taken within each plot. Spring sampling was done on April 20, 2000 and May 10, 2001. Post harvest sampling was done September 15, 2000 and September 20, 2001. Copper levels were determined using DTPA extractant by NorWest Laboratories (Winnipeg).

Whole plant harvest from four areas (1 row x 1.0 metre long) of each plot was done at the soft dough kernel stage to determine biomass (done only in 2000). Analysis was conducted by NorWest Laboratories (Winnipeg).

Plants were visually assessed for copper deficiencies at head emergence (July). Flagleafs were sampled from 50 plants per plot to determine copper status of plants. Sampling was done three weeks or more after the last foliar copper application in an attempt to avoid copper fertilizer residue on the leaf.

Combined grain yields were determined with a weigh wagon at the Smith site in 2000, and by combine yield monitor for the other three sites. Grain samples were collected during the combining operation as grain flowed into the grain tank. Grain was analyzed for protein content (Grainspec), grade, test weight, dockage, fusarium-damaged kernels (FDK) and ergot percentage by Delmar Commodities (Mariapolis) in 2000 and Agricore United (Somerset) in 2001. The sprout percentage was also determined in the 2000 studies. Central Testing Labs in Winnipeg determined vomitoxin content as DON concentration of grain.

Data was analyzed using the AGROBASE statistical program using analysis of variance (ANOVA). Data was analyzed across the four-site years and by individual site. Mean separation was done when differences were determined to be significant at the 5% probability level.

Economic analysis was determined with the returns (based on yield and quality changes) and cost of the treatments (product and application).

Results and Discussion:

Complete analysis of measurements is summarized in Table 1 across all four-site years. Individual site analysis is reported in Tables 2-5.

Table 1.  CWRS response to applied copper across 4 site years.

Means in the column followed by the same letter are not significantly different at the 5% probability level.

Where differences were significant at the 10% probability level, they are indicated as 10%.

Table 2.  CWRS response to applied copper at Cavers site in 2000 (0.8 ppm in fall 1999)