2004 CORN ROOTWORM SOIL INSECTICIDE / SEED TREATMENT

EFFICACY AND YIELD EXPERIMENT

 

 

 

 

 

 

University of Nebraska

Agricultural Research and Development Center

Mead, Nebraska

 

 

 

 

 

 

Lance J. Meinke, Jim Brown,

 Laura Campbell, Bill McCormick

 

Department of Entomology

University of Nebraska

Lincoln, Nebraska  68583-0816

           

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Background information pertaining to the experiment conducted at the ARDC, near Mead, Nebraska during 2004.

Background Information - AgronomicBackground Information - Entomology
Experimental DesignEnvironmental Conditions at Planting
Rainfall and Irrigation Root Damage Evaluations

Agronomic

 

            Hybrids:                                     DKC 60-15, DKC-12

            Row Spacing:                             30 inches

            Planting Date:                             23 April 2004

            Planter:                                       Kinze model 2100, 4 row cone

            Planting Depth:                           2 inches

            Application Equipment:               Granular insecticide 

                                                              Planting: planter mounted cone-belt system

                                                              Liquid insecticide

                                                              Planter mounted CO2 pressurized sprayer

            Field Preparation:                       20 April 2004 - disked

            Herbicides Applied:                    23 April 2004: Harness Xtra,  2.5 qt/A, pre emerge

                                                              10 June 2004: 1.0 oz Permit + 0.67 oz Accent / A

            Fertilizer Applied:                    150 lb. N/A applied as NH3, 15 April 2004                                         

            Previous Crop:                           Continuous corn (trap crop)

            Harvest date:                              Hand harvested 100 ft of center two rows per plot, October 2004

 

            Soil Information:                                             

                  Type:                                    Silty clay loam              

                  Ph:                                                6.4                                  

                  CEC:                                          29.4                                 

                  % organic matter:                          2.8                                  

                  % clay:                                       29.05                                

                  % silt:                                         66.67                               

                  % sand:                                        4.28                                

 

            Plant Population:                          There were significant differences (P < 0.05) among treatment

stand count means at harvest. Final stand counts presented in Table 1.

           

            Insecticide History:                      Insecticide free: 1997, 1999, 2001, 2003

                                                               Multiclass soil insecticide trials: 1996, 1998, 2000, 2002

                                                                                                                                                                       

Entomological

 

                  Species present:                     Northern corn rootworm, Diabrotica barberi Smith and Lawrence, and western corn rootworm, D. virgifera virgifera LeConte.  Initial rootworm egg hatch occurred between 22-23 May 2004 (predominantly western corn rootworm).

 

Root Evaluation:                    1-6 (Hills and Peters 1971) and 0-3 root rating scales (J. Oleson, Iowa State University) were used to evaluate larval corn rootworm damage in each treatment.  Five roots per replication were evaluated in each treatment.

 

                  Root Evaluation Date:            14 July 2004

                                                              

 

Experimental Design

 

Design: Randomized complete block design

                                                                    Replicated four times

                                                                    Four-row treatments

                                                                   

            Row Length:                               60 feet

 

            Statistical Analysis:                      Stand Counts, Root Ratings, Yields: Used SAS Mixed Procedure; Protected LSD test was used for mean separation (P < 0.05) .

 

 

Environmental

 

 

            Conditions at planting:

 

                  Air temperature:                                  24EC

                  Wind speed:                                       12 mph at 5 ft height

                  Wind direction:                                   N - NE

                  Soil temperature 2" depth:                   17EC

                  Soil temperature surface:                     27EC

                  Soil moisture, 0-3" depth:                    9 % water (gravimetric method)

                  % cloud cover:                                   70 % cloud cover (high haze)

                  % relative humidity:                             not recorded

                  Residue on surface:                             20% of soil surface covered with crop residue; soil moist, some clods on surface

 

 

 

 

 

 

Rainfall

 
April090.039 inches
 180.039 inches
 200.039 inches
 240.787 inches
Total0.904 inches

 

May010.039 inches
 100.512 inches
 120.039 inches
 130.079 inches
 140.039 inches
 150.039 inches
 160.039 inches
 170.039 inches
 180.118 inches
 221.890 inches
 240.236 inches
 260.157 inches
 291.063 inches
Total4.289 inches

 

June050.236 inches
 122.323 inches
 130.079 inches
 150.118 inches
 180.236 inches
 210.236 inches
 240.039 inches
Total3.267 inches

 

July020.906 inches
 030.236 inches
 050.157 inches
 060.079 inches
 070.354 inches
 080.039 inches
 110.118 inches
 140.236 inches
 220.039 inches
 230.039 inches
 240.039 inches
 290.039 inches
 300.039 inches
Total2.320 inches

 

August080.039 inches
 120.039 inches
 251.496 inches
Total1.574 inches

 

 

 


Irrigation:

 

Sprinkler irrigation was applied periodically as needed.

 

July021.0 inch
 201.0 inch
 211.0 inch
 301.5 inch
   
August170.5 inch

 

 

 

 

 

Table 1.   2004 Corn Rootworm Soil Insecticide / Neonicotinoid

Seed Treatment Efficacy and Yield Experiment

 

University of Nebraska Agricultural Research and Development Center, near Mead, NE

 

 Root Damage Rating, Final Stand, and Lodging + SE

 

 

TreatmentTreatment RateMean Root Rating1
1 - 6 Scale		Mean Root Rating1
0 - 3 Scale		Final Stand2Percentage
Lodging3
MON 863 DKC 60-12
plus Poncho 250		Clothianidin 0.25 mg ai/seed2.25 + 0.2a0.08 + 0.03a143.0 + 6.5a0.0 + 0.0
Isoline DKC 60-15
plus Poncho 1250 and Force 3G		Force 3.0G 0.12 oz ai/1000' T-band
Clothianidin 1.25 mg ai/seed		2.50 + 0.1ab0.14 + 0.01a146.7 + 6.0a0.0 + 0.0
Isoline DKC 60-15
plus Regent 4 SC		0.13 lb ai/A, 5 gpa microtube infurrow application3.15 + 0.3abc0.62 + 0.2ab146.0 + 2.3a1.9 + 1.0
Isoline DKC 60-15
plus Force 3G		Force 3.0G 0.12 oz ai/1000' T-band3.40 + 0.6bc0.85 + 0.6ab149.7 + 3.1a2.6 + 1.0
Isoline DKC 60-15
plus Poncho 1250		Clothianidin 1.25 mg ai/seed3.80 + 0.3cd1.16 + 0.3bc150.5 + 6.3a5.1 + 2.6
Isoline DKC 60-15
plus Poncho 250		Clothianidin 0.25 mg ai/seed4.50 + 0.3de1.75 + 0.2cd149.0 + 5.8a24.5 + 2.9
Isoline DKC 60-15
plus Cruiser 5 FS		Thiamethoxam 1.25 mg ai/seed4.85 + 0.3ef2.06 + 0.2de147.2 + 1.9a29.4 + 8.8
Isoline DKC 60-15
 5.75 + 0.2f2.83 + 0.1e93.5 + 3.0

Planting date: 23 April 2004;  Plot size: four rows x 60 ft per treatment per replication, 4 replications; means within columns followed by the same letter are not significantly different (P > 0.05, Fishers Protected LSD Test).

1 Root evaluation date: 14 July 2004, rated 5 roots per treatment per replication

2 Final stand = number of plants per 100 ft harvested in two center rows of each plot, stands recorded during October 2004

3 Percentage lodging = proportion of final stand leaning >45 degree angle x 100

 

 

 

 

Table 2.   2004 Corn Rootworm Soil Insecticide / Neonicotinoid

Seed Treatment Efficacy and Yield Experiment

University of Nebraska Agricultural Research and Development Center, near Mead, NE

 Yield + SE

TreatmentTreatment RateBulk Yield 1
Per Acre (bushels)		Yield Per 2
Plant (lbs)
Isoline DKC 60-15
plus Poncho 1250 and Force 3G		Force 3.0G 0.12 oz ai/1000' T-band
Clothianidin 1.25 mg ai/seed		217.50 + 8.0 a0.478 + 0.02a
MON 863 DKC 60-12
plus Poncho 250		Clothianidin 0.25 mg ai/seed214.00 + 7.2 a0.482 + 0.01 a
Isoline DKC 60-15
plus Regent 4 SC		0.13 lb ai/A, 5 gpa microtube
infurrow application		209.67 + 4.1a0.462 + 0.01ab
Isoline DKC 60-15
plus Force 3G		Force 3.0G 0.12 oz ai/1000' T-band208.36 + 8.8 a0.448 + 0.02ab
Isoline DKC 60-15
plus Poncho 1250		Clothianidin 1.25 mg ai/seed204.32 + 4.5 a0.438 + 0.01 ab
Isoline DKC 60-15
plus Poncho 250		Clothianidin 0.25 mg ai/seed200.69 + 8.8 a0.432 + 0.01 ab
Isoline DKC 60-15
plus Cruiser 5 FS		Thiamethoxam 1.25 mg ai/seed190.86 + 7.4 a0.416 + 0.01 b
Isoline DKC 60-15
 117.99 + 21.4 b0.313 + 0.04 c

Planting date: 23 April 2004; Plot size: four rows x 60 ft per treatment per replication, 4 replications; means within columns followed by the same letter are not significantly different (P > 0.05, Fishers Protected LSD Test)

1 Bulk yields: hand harvested and shelled middle 50 ft of the two inside rows / plot during October 2004, presented as bushels of corn @ 15.5% moisture

2 Yield per plant = lbs. bulk yield divided by final stand count