A field study was planted on April 29 at the NDSU Langdon Research Extension Center located in Langdon, ND. The trial experimental design was a randomized complete block with four replications. Plots were seven rows spaced at six inch row spacing and a row length of 20 feet trimmed to 15 feet for harvest. The variety ‘Vantage’ was seeded at a rate of 1.2 million pure live seeds/a. An untreated border plot was planted between treated plots to minimize interference from spray drift. The previous crop was hrsw. Huskie Complete (1 pt/a) + Prowl H20 (2.7 pt/a) were used to control weeds. The plots were inoculated by spreading corn spawn inoculum at boot stage (Feekes 9-10) at a rate of 286g/plot. Supplemental moisture was provided by running overhead irrigation from Feekes 10.5 to 11.25 at the rate of one hour per day to provide a conducive environment for Fusarium Head Blight (FHB) development. Fungicides were applied with a CO2 backpack sprayer equipped with a three nozzle boom (XR8001) operated at 40 psi delivering a water volume of 10 GPA. Fungicide application was made at Feekes 10.51 (10% flowering) on July 9 (wind speed 12 MPH, 75O F at 2:30pm).
Percent FHB incidence (INC) was calculated by counting the number of heads showing FHB symptoms from 50 randomly selected heads, excluding the two outer rows. FHB severity (SEV) was rated using a 0-100% scale from those same heads. FHB index (FHBI) was calculated using the formula FHBI=(SEV*INC)/100. Plots were harvested on August 21 with a plot combine. Yield and test weight were determined. Statistical analysis was done using SAS. Fisher’s least significant difference (LSD) was used to compare means at P≤0.05.
Results
The lowest FHB incidence and severity was with Caramba at 13.5 fl oz/a while the highest FHB incidence and severity was with the untreated check. Prosaro at 6.5 fl oz/a had the lowest FHB index and the untreated check had the highest.
The treatments Caramba at 13.5 fl oz/a and Prosaro at 6.5 fl oz/a had the highest yields while the lowest yield was in the untreated check.
Table 1. Fungicide treatment effects on Fusarium head blight and yield of ‘Vantage’ spring wheat, Langdon 2015.
| Rate of | Application | | | | |
|---|
| Application | Timing | Fusarium Head Blight | Yield |
Treatment | (fl oz/a) | (Feekes) | % Incidence | % Severity | Index | (bu/a) |
Tebustar + NIS | 4.0 | 10.51 | 39 | 39 | 15.6 | 37.5 |
Muscle 3.6F + NIS | 4.0 | 10.51 | 46 | 35 | 15.8 | 38.9 |
Orius + NIS | 4.0 | 10.51 | 45 | 35 | 15.6 | 38.0 |
Aproach Prima | 6.8 | 10.51 | 37 | 28 | 10.3 | 43.3 |
Aproach + NIS | 12.0 | 10.51 | 44 | 27 | 12.2 | 44.4 |
Untreated Check | -- | -- | 55 | 41 | 22.7 | 32.6 |
Prosaro + NIS | 8.2 | 10.51 | 48 | 33 | 15.2 | 41.2 |
Caramba + NIS | 13.5 | 10.51 | 23 | 9 | 10.8 | 47.1 |
Onset + NIS | 4.0 | 10.51 | 50 | 32 | 15.6 | 41.1 |
Prosaro + NIS | 6.5 | 10.51 | 36 | 26 | 9.2 | 46.9 |
Caramba + NIS | 17.0 | 10.51 | 39 | 21 | 9.3 | 43.6 |
Toledo + NIS | 4.0 | 10.51 | 40 | 27 | 10.9 | 39.7 |
Teagro + Prosaro | 5.2 | 10.51 | 40 | 28 | 11.3 | 40.7 |
Monsoon + NIS | 4.0 | 10.51 | 46 | 32 | 14.8 | 38.3 |
Trial Mean | | | 42 | 30 | 13.5 | 40.9 |
C.V. % | | | 39.6 | 29.3 | 52.1 | 9.2 |
LSD 5% | | | 17.1 | 12.4 | 10.0 | 5.4 |
All treatments were applied with NIS @ 0.125% v/v.
Acknowledgements: This trial was funded by Andrew Friskop through USWB Scab Initiative.
