2023: Insecticide Seed Treatments for Flea Beetle Control in Spring Canola
(Research Report, Langdon REC, December 2023)Materials and Methods
The trial was conducted at three different locations; NDSU Campus Agronomy farm in Fargo, Langdon REC in Langdon, and North Central REC in Minot. In Table 1, the planting dates, trial design, seeding rates and other information for LREC are summarized.
Table 1. Location, experiment and agronomic information.
Langdon | |
|---|---|
| Trial Latitude (LLC) | 48.750036 |
| Trial Longitude (LLC) | -98.333301 |
| Canola Variety | DKTFLL 21 SC |
| Previous Crop | HRSW |
| Planting Date | May 22 |
| Emergence Date | May 28 |
| Plot Size | 3.5 ft x 20 ft |
| Row Spacing | 6 inches |
| Seeding Depth | 0.75 inch |
| Seeding Rate | 14 seeds/ft2 |
| Experimental Design | RCBD, 4 reps |
| Harvest Date | September 18 |
Seed treatment efficacy was examined for control of crucifer and striped flea beetles in spring canola. Treatments, rates and active ingredients are listed in Table 2. Dekalb DKTFLL 21 SC canola seed was treated prior to planting. Two neonicotinoid seed treatments, Helix Vibrance (thiamethoxam) and Prosper Evergol (clothianidin) were tested alone and in combination with three rates of either Lumiderm or Fortenza (cyantraniliprole). Prosper Evergol also was tested in combination with two rates of Buteo Start (flupyradifurone) and in combination with the commercial rates of Lumiderm. In addition to testing seed treatment efficacy, we tested a single foliar application of bifenthrin at 2.6 fl oz per acre in combination with certain seed treatments (Treatments 6, 11 and 15) and compared these to the seed treatments alone. We attempted to make applications at the nominal threshold of 20 to 25% defoliation (approximately a rating of 2 on the 0-6 scale). At Langdon, the foliar application to Treatment 11 was made on June 1 at 4 days after emergence (DAE), to Treatment 6 on June 2 at 5 DAE, and to Treatment 15 on June 9 at 12 DAE. Foliar applications were made with a hand boom using TeeJeet 11015 flat fan nozzles at 40 PSI and a carrier volume of 20 GPA.
Plots were rated for flea beetle feeding injury using the 0-6 scale developed by Dr. Janet Knodel, with 0 = no feeding and 6 = dead plant. Within each plot, 10 randomly selected seedlings were rated. For analysis, the 10 ratings were averaged for a single rating value per plot. Feeding injury was rated at 3, 7, 10 and 14 DAE. Plant stand was measured after the last injury ratings were made by counting the number of live plants in three square feet at two locations within each plot, and calculating the number of plants per square foot. Plots were harvested at maturity by swathing prior to combining. Yield, percent moisture content, and test weight were collected via the onboard weigh systems on the plot combines. Yields were adjusted to 10% standard grain moisture. All data were analyzed using the GLM procedure in SAS version 9.4 statistical software. Fisher’s LSD (P<0.05) was used to test for significance among treatment means. Sampling activities, dates and crop stages for the Langdon trial are given in Table 3.
Table 2. Treatments, active ingredients and rates used in the trial.
Treatment No. | Treatment Name | Product Rate(s) | Active Ingredient(s) | AI Rate(s) |
|---|---|---|---|---|
1 | Fungicide Check |
|
|
|
2 | Helix Vibrance | 23 fl oz/cwt | Thiamethoxam | 400 g/100 kg |
3 | Helix Vibrance Fortenza1,2 | 23 fl oz/cwt 10.2 fl oz/cwt | Thiamethoxam Cyantraniliprole | 400 g/100 kg 400 g/100 kg |
4 | Helix Vibrance Fortenza1 | 23 fl oz/cwt 15.4 fl oz/cwt | Thiamethoxam Cyantraniliprole | 400 g/100 kg 600 g/100 kg |
5 | Helix Vibrance Fortenza1 | 23 fl oz/cwt 20.5 fl oz/cwt | Thiamethoxam Cyantraniliprole | 400 g/100 kg 800 g/100 kg |
6 | Helix Vibrance Fortenza1,2 Brigade 2EC | 23 fl oz/cwt 10.2 fl oz/cwt 2.6 fl oz/acre | Thiamethoxam Cyantraniliprole Bifenthrin | 400 g/100 kg 400 g/100 kg 18.4 g/acre |
7 | Prosper Evergol | 21.5 fl oz/cwt | Clothianidin | 400 g/100 kg |
8 | Prosper Evergol Lumiderm2 | 21.5 fl oz/cwt 9.8 fl oz/cwt | Clothianidin Cyantraniliprole | 400 g/100 kg 400 g/100 kg |
9 | Prosper Evergol Lumiderm | 21.5 fl oz/cwt 14.8 fl oz/cwt | Clothianidin Cyantraniliprole | 400 g/100 kg 600 g/100 kg |
10 | Prosper Evergol Fortenza1 | 21.5 fl oz/cwt 20.5 fl oz/cwt | Clothianidin Cyantraniliprole | 400 g/100 kg 800 g/100 kg |
11 | Prosper Evergol Lumiderm2 Brigade 2EC | 21.5 fl oz/cwt 9.8 fl oz/cwt 2.6 fl oz/acre | Clothianidin Cyantraniliprole Bifenthrin | 400 g/100 kg 400 g/100 kg 18.4 g/acre |
12 | Prosper Evergol Buteo Start3 | 21.5 fl oz/cwt 9.6 fl oz/cwt | Clothianidin Flupyradifurone | 400 g/100 kg 300 g/100 kg |
13 | Prosper Evergol Buteo Start | 21.5 fl oz/cwt 16 fl oz/cwt | Clothianidin Flupyradifurone | 400 g/100 kg 500 g/100 kg |
14 | Prosper Evergol Lumiderm2 Buteo Start3 | 21.5 fl oz/cwt 9.8 fl oz/cwt 9.6 fl oz/cwt | Clothianidin Cyantraniliprole Flupyradifurone | 400 g/100 kg 400 g/100 kg 300 g/100 kg |
15 | Prosper Evergol Buteo Start3 Brigade 2EC | 21.5 fl oz/cwt 9.6 fl oz/cwt 2.6 fl oz/acre | Clothianidin Flupyradifurone Bifenthrin | 400 g/100 kg 300 g/100 kg 18.4 g/acre |
1Fortenza substituted for Lumiderm, rate(s) adjusted to match Lumiderm cyantraniliprole concentration.
2Commercial Lumiderm rate when used in combination with a neonicotinoid.
3Commercial Buteo Start rate when used in combination with a neonicotinoid.
Results
Treatment means for response variables from the Langdon location are presented in Table 4 (data from Fargo and Minot locations is available in a detailed report available at the LREC website). Flea beetle density and feeding pressure at Langdon was moderately high. Both crucifer and striped flea beetles were present with crucifer flea beetles being the dominant species. While some significant differences exist among treatments and locations due to differences in flea beetle species and densities, and sampling timing among locations, we feel we can make valid inferences about treatment performance as a whole by combining the data from all locations (Table 5, Figure 1).
Table 3. Sampling activities, sampling dates, and crop stages.
| Langdon | ||
|---|---|---|---|
Activity | Date | DAE | Crop Stage |
Injury Rating 1 | May 31 | 3 DAE | Cotyledon |
Injury Rating 2 | June 4 | 7 DAE | 1-leaf |
Canopy Cover 1 | --- | --- | --- |
Injury Rating 3 | June 7 | 10 DAE | 2-leaf |
Canopy Cover 2 | --- | --- | --- |
Injury Rating 4 | June 11 | 14 DAE | 3-leaf |
Canopy Cover 3 | --- | --- | --- |
Stand Counts | June 12 | 15 DAE | 3-leaf |
There were no significant differences for flea beetle injury, canopy cover and yield between Helix Vibrance and Prosper Evergol when used alone, or in combination with different rates of cyantraniliprole (Lumiderm / Fortenza). Increasing cyantraniliprole rates above the commercially available rate decreased flea beetle injury and increased yield, but the treatment means were not significantly different except for an increase in yield for Helix Vibrance + Fortenza at 20.5 fl oz/cwt at Langdon. Prosper Evergol combined with Buteo Start resulted in significantly less flea beetle injury and significantly higher yields compared to the neonicotinoids alone and in combination with all rates of cyantraniliprole (Lumiderm / Fortenza), except for yield when a neonicotinoid was combined with the 800 g ai/100 kg cyantraniliprole rate (Lumiderm / Fortenza). Increasing the Buteo Start rate did not give any improvement over the commercially available rate, nor did adding cyantranilprole (Lumiderm / Fortenza) to Buteo Start.
A single foliar application of Brigade 2EC at 2.6 fl oz/acre at the nominal threshold of 20 to 25% defoliation, in combination with a neonicotinoid plus the commercially available rates of cyantraniliprole or Buteo Start, generally resulted in significantly higher yields and lower flea beetle injury compared to all treatments without Brigade 2EC, except for treatments containing Prosper Evergol and Buteo Start, and Helix Vibrance plus Fortenza at 20.5 fl oz/cwt (yield only).
The addition of cyantraniliprole at the commercial rate of 400 g ai/100 kg to either neonicotinoid resulted in less flea beetle injury at 3 DAE compared to using a neonicotinoid alone, but not at 7 DAE or beyond. Nor did the addition of the commercial cyantraniliprole rate result in significantly higher yield compared to the neonicotinoids alone. The addition of Buteo Start at the commercial rate of 300 g ai/100 kg to Prosper Evergol resulted in significantly less flea beetle injury compared to neonicotinoids alone or in combination with cyantraniliprole at the commercial rate, and also resulted in significantly higher yield. The addition of cyantraniliprole to the Prosper Evergol/Buteo Start mix did not have a significant effect.
Using our yield results for treatments across locations, we constructed the following table to calculate profitability based on different commercially available seed treatment scenarios with and without a foliar insecticide application (Table 6). This assumes a canola market value of $28.10/cwt, a seed treatment cost of $8.00/acre/product, and a foliar insecticide application cost of $11.12/acre for a generic bifenthrin product at 2.6 fl oz/acre.
Conclusion
Based on our results, we recommend that canola producers take the following steps to maximize yield potential by protecting seedlings and maximizing seedling health through at least the 4 to 6 leaf growth stage.
- Use a base seed treatment of either Helix Vibrance (thiamethoxam) or Prosper Evergol (clothianidin) and combine with either Lumiderm or Fortenza (cyantraniliprole) at 400 g ai/100 kg or Buteo Start (flupyradifurone) at 300 g ai/100 kg.
- Scout for flea beetle injury frequently, especially from 3 DAE through 21 DAE.
- Budget for a foliar application of insecticide at highest labeled rate when defoliation is above 20 to 25% defoliation (Economic Threshold).
- Apply foliar insecticide quickly when above the Economic Threshold of 20 to 25% defoliation.
- A good weed control program will help seedling vigor and growth.
- Proper fertility, including sulfur, will help seedling vigor and growth.
Acknowledgements
We would like to thank the Northern Canola Growers Association and our field workers, Joslin Forness and Miro Herrera Grant. We also appreciate the untreated canola seed supplied by Jim Johnson of Star Specialty Seeds.
Table 4. Treatment means for flea beetle injury, plant stand, test weight, and grain yield at Langdon, 2023.
Trt. No. | Treatment | Injury 3 DAE | Injury 7 DAE | Injury 10 DAE | Injury 14 DAE | Plant Stand (plants/ft2) | Test Weight (lbs/bu) | Grain Yield (lbs/acre) |
|---|---|---|---|---|---|---|---|---|
1 | Fungicide Check | 4.5 a | 5.2 a | 4.8 a | 4.9 a | 3.8 d | 51.4 bc | 2,236.5 f |
2 | Helix Vibrance @ 23 | 1.5 bcd | 4.1 bc | 4.6 ab | 4.5 ab | 7.7 abc | 51.7 abc | 2,578.2 ef |
3 | Helix Vibrance @ 23 Fortenza @ 10.2 | 1 cde | 3.4 b-e | 4 c | 4.1 bc | 8.5 abc | 51.7 abc | 2,963.7 b-e |
4 | Helix Vibrance @ 23 Fortenza @ 15.4 | 0.9 c-f | 3.1 de | 3.9 c | 4.2 bc | 7.6 abc | 51.6 abc | 2,969.1 b-e |
5 | Helix Vibrance @ 23 Fortenza @ 20.5 | 0.8 def | 2.6 e | 4 c | 4.2 abc | 9.3 ab | 52 ab | 3,255.5 a-d |
6 | Helix Vibrance @ 23 Fortenza @ 10.2 Brigade 2EC @ 2.6 | 0.9 c-f | 1.8 f | 2.3 de | 3.1 de | 8.4 abc | 52 ab | 3,622.9 a |
7 | Prosper Evergol @ 21.5 | 2.3 b | 4.2 c | 4.3 ab | 4.5 ab | 7.3 bc | 51.4 bc | 2,728 ef |
8 | Prosper Evergol @ 21.5 Lumiderm @ 9.8 | 1.7 bc | 3.7 bcd | 4.1 bc | 4.7 ab | 7.1 bc | 51.6 abc | 2,839.1 de |
9 | Prosper Evergol @ 21.5 Lumiderm @ 14.8 | 1.2 cd | 3.8 bcd | 4 c | 4.3 ab | 9.9 a | 52.1 a | 3,014.4 b-e |
10 | Prosper Evergol @ 21.5 Fortenza @ 20.5 | 0.9 c-f | 3.3 cde | 4 c | 4.4 ab | 8.5 abc | 51.8 ab | 2,936.1 cde |
11 | Prosper Evergol @ 21.5 Lumiderm @ 9.8 Brigade 2EC @ 2.6 | 1.1 cd | 1.6 fg | 2.5 de | 2.8 e | 8.4 abc | 51.4 abc | 3,383.6 abc |
12 | Prosper Evergol @ 21.5 Buteo Start @ 9.6 | 0.3 ef | 1.2 fg | 2.8 d | 3.4 de | 7 c | 51.8 ab | 3,369.4 abc |
13 | Prosper Evergol @ 21.5 Buteo Start @ 16 | 0.1 f | 0.9 g | 2.1 e | 2.9 de | 8.3 abc | 51.1 c | 3,486.8 ab |
14 | Prosper Evergol @ 21.5 Lumiderm @ 9.8 Buteo Start @ 9.6 | 0.3 ef | 1.4 fg | 2.8 d | 3.6 cd | 7.6 abc | 51.9 ab | 3,655.3 a |
15 | Prosper Evergol @ 21.5 Buteo Start @ 9.6 Brigade 2EC @ 2.6 | 0.2 ef | 1.2 fg | 2.6 de | 3 de | 7.5 bc | 51 c | 3,386 abc |
F-value | 14.16 | 20.59 | 20.15 | 8.93 | 2.82 | 1.80 | 4.79 | |
P-value | <0.0001 | <0.0001 | <0.0001 | <0.0001 | 0.0047 | 0.0721 | <0.0001 | |
LSD | 0.82 | 0.84 | 0.57 | 0.68 | 2.32 | 0.67 | 526.84 |
Means within a column that share the same letter are not significantly different (P<0.05).
Table 5. Treatment means for flea beetle injury, canopy cover, plant stand, test weight, and grain yield across locations, 2023.
Trt. No. | Treatment | Injury 3 DAE | Injury 7 DAE | Injury 10 DAE | Injury 14 DAE | Canopy 7 DAE | Canopy 10 DAE | Canopy 14 DAE | Plant Stand (plants/ft2) | Test Weight (lbs/bu) | Grain Yield (lbs/acre) |
|---|---|---|---|---|---|---|---|---|---|---|---|
1 | Fungicide Check | 4.1 a | 4.4 a | 4.3 a | 3.8 a | 4.9 a | 14.9 c | 41.1 c | 6.7 e | 52.1 e | 1762.9 d |
2 | Helix Vibrance @ 23 | 2.4 bc | 3.6 b | 3.8 b | 3.3 b | 5.3 a | 26.7 ab | 53.1 ab | 9.4 bcd | 52.3 b-e | 2195.1 c |
3 | Helix Vibrance @ 23 Fortenza @ 10.2 | 1.5 e | 3 bcd | 3.2 cde | 3 bcd | 6 a | 23.4 ab | 49.6 b | 10.2 abc | 52.6 a-e | 2374.6 c |
4 | Helix Vibrance @ 23 Fortenza @ 15.4 | 1.6 de | 2.8 cd | 3.1 cde | 3.2 b | 5.8 a | 26.8 ab | 54.2 ab | 9.2 cd | 52.5 a-e | 2394.1 c |
5 | Helix Vibrance @ 23 Fortenza @ 20.5 | 1.3 ef | 2.5 de | 3.2 cd | 3.2 bcd | 6.4 a | 23.7 ab | 52.8 ab | 10.3 abc | 52.9 a | 2632.2 ab |
6 | Helix Vibrance @ 23 Fortenza @ 10.2 Brigade 2EC @ 2.6 | 1.4 ef | 2 ef | 1.9 gh | 2.4 fg | 6.1 a | 23.8 ab | 54.6 ab | 10 a-d | 52.8 ab | 2841.4 a |
7 | Prosper Evergol @ 21.5 | 2.8 b | 3.5 bc | 3.8 ab | 3.3 b | 4.7 a | 21.8 b | 49.8 b | 8.9 d | 52.2 de | 2281.4 c |
8 | Prosper Evergol @ 21.5 Lumiderm @ 9.8 | 2 cd | 3.3 bc | 3.4 bc | 3.3 b | 6.1 a | 25.5 ab | 54.4 ab | 9.4 bcd | 52.4 b-e | 2347 c |
9 | Prosper Evergol @ 21.5 Lumiderm @ 14.8 | 1.6 de | 3.2 bc | 3.2 cde | 3.1 bcd | 6.9 a | 27.8 ab | 54.9 ab | 10.6 a | 52.7 abc | 2382.2 c |
10 | Prosper Evergol @ 21.5 Fortenza @ 20.5 | 1.6 de | 3.1 bcd | 3 cde | 3.2 bc | 5.5 a | 27.3 ab | 54.3 ab | 9.7 a-d | 52.5 a-e | 2416.6 bc |
11 | Prosper Evergol @ 21.5 Lumiderm @ 9.8 Brigade 2EC @ 2.6 | 1.5 e | 2 ef | 2 gh | 2.1 gh | 7.1 a | 26.1 ab | 56.2 a | 10.4 ab | 52.7 abc | 2830.5 a |
12 | Prosper Evergol @ 21.5 Buteo Start @ 9.6 | 1.2 ef | 1.7 f | 2.9 de | 2.8 de | 6.4 a | 24.5 ab | 54.2 ab | 9.3 bcd | 52.8 abc | 2638.9 ab |
13 | Prosper Evergol @ 21.5 Buteo Start @ 16 | 0.6 g | 1.4 f | 2.3 fg | 2.6 ef | 6.4 a | 27.3 ab | 54.9 ab | 10 a-d | 52.3 cde | 2668.6 a |
14 | Prosper Evergol @ 21.5 Lumiderm @ 9.8 Buteo Start @ 9.6 | 0.9 fg | 1.7 f | 2.8 ef | 2.8 cde | 6 a | 29.2 a | 55.8 a | 9.8 a-d | 52.6 a-d | 2732.6 a |
15 | Prosper Evergol @ 21.5 Buteo Start @ 9.6 Brigade 2EC @ 2.6 | 0.9 fg | 1.5 f | 1.9 h | 2 h | 6 a | 28.2 ab | 57.7 a | 9.6 a-d | 52.4 b-e | 2849.2 a |
F-value | 23.19 | 14.20 | 19.23 | 13.74 | 1.60 | 2.08 | 3.56 | 5.18 | 1.97 | 13.43 | |
P-value | <0.0001 | <0.0001 | <0.0001 | <0.0001 | 0.12 | 0.02 | <0.0001 | <0.0001 | 0.03 | <0.0001 | |
LSD | 0.51 | 0.67 | 0.45 | 0.37 | NS | 6.82 | 5.90 | 1.13 | 0.45 | 225.09 |
Means within a column that share the same letter are not significantly different (P<0.05).
Table 6. Crop market values when using different insecticide seed treatment and foliar insecticide application options.
| Market Value | Yield | Crop Value | ST Cost | Foliar Cost | Total Cost | Net |
|---|---|---|---|---|---|---|---|
Treatment | (USD/cwt) | (lbs/acre) | (USD/acre) | (USD/acre) | (USD/acre) | (USD/acre) | (USD/acre) |
| Fungicide Check | $28.10 | 1,762.9 | $495.37 | $- | $- | $- | $495.37 |
| Helix Vibrance1 | $28.10 | 2,195.1 | $616.82 | $8.00 | $- | $8.00 | $608.82 |
Helix Vibrance1 Fortenza3 | $28.10 | 2,374.6 | $667.26 | $16.00 | $- | $16.00 | $651.26 |
Helix Vibrance1 Fortenza3 Bifenthrin5 | $28.10 | 2,841.4 | $798.43 | $16.00 | $11.12 | $27.12 | $771.31 |
| Prosper Evergol2 | $28.10 | 2,281.4 | $641.07 | $8.00 | $- | $8.00 | $633.07 |
Prosper Evergol2 Lumiderm3 | $28.10 | 2,347 | $659.51 | $16.00 | $- | $16.00 | $643.51 |
Prosper Evergol2 Lumiderm3 Bifenthrin5 | $28.10 | 2,830.5 | $795.37 | $16.00 | $11.12 | $27.12 | $768.25 |
Prosper Evergol2 Buteo Start4 | $28.10 | 2,638.9 | $741.53 | $16.00 | $- | $16.00 | $725.53 |
Prosper Evergol2 Buteo Start4 Bifenthrin5 | $28.10 | 2,849.2 | $800.63 | $16.00 | $11.12 | $27.12 | $773.51 |
1Helix Vibrance at 23 fl oz/cwt (thiamethoxam at 400 g ai/100 kg)
2Prosper Evergol at 21.5 fl oz/cwt (clothianidin at 400 g ai/100 kg)
3Fortenza at 10.2 fl oz/cwt or Lumiderm at 9.8 fl oz/cwt (cyantraniliprole at 400 g ai/100 kg)
4Buteo Start at 9.6 fl oz/cwt (flupyradifurone at 300 g ai/100 kg)
5Bifenthrin 2EC at 2.6 fl oz/acre
Figure 1. Treatment means for flea beetle injury and yield across ND locations, 2023.
