Stubby-root nematodes are ectoparasites that live entirely in the soil and feed on root tips.
Damage: They are important pests of potato because they transmit Tobacco rattle virus (TRV), which is the causal agent of corky ringspot disease. Symptoms of corky ringspot include internal brown arcs, rings, or blotches inside the tuber, and arc-shaped lesions on the tuber surface. Stubby-root nematodes rarely damage potatoes without the virus, but they can cause significant stunting of more susceptible plants like onions.
Control: The treatment threshold is upon detection of the nematode when corky ringspot is a concern, but it is often set at 200 or more nematodes per 100 cc soil in fields that are not infested with TRV.
| Stage of Development: Planting to Pre-emergence | ||||||
|---|---|---|---|---|---|---|
| Pesticide | MOA1 | Efficacy2 | Rate per Acre3 | REI4 | PHI5 | Notes |
| Vydate C-LV oxamyl | 1A | G | 2.1-4.25 pt | 48 h | 7 d | Start with an in-furrow application at planting and follow with foliar applications via chemigation. The in-furrow application is optional but is recommended to risk-averse growers and when following alfalfa. Corky ringspot may not be controlled if nematodes are not suppressed prior to tuber initiation. |
1Mode of action. NC = not classified..
2 Efficacy ratings denote the relative ability of a pesticide to control its target. The ratings are E = excellent, G = good, F = fair/suppression; P = poor, and ND = no data. Efficacy ratings are based on the inherent toxicity of the pesticide against its target, the likelihood that the target will contact or ingest the product as applied, duration of impact on the target, and undesired effects, such as negative impacts on natural enemies that could lead to future pest outbreaks.
3 Rate per acre per application. Refer to the product label for maximum use rate per season.
4 Reentry interval.
5The minimum pre-harvest interval. Some products do not list PHI.
Note: always read and follow the directions on the pesticide label.
| Stage of Development: Emergence to Row Closure | ||||||
|---|---|---|---|---|---|---|
| Pesticide | MOA1 | Efficacy2 | Rate per Acre3 | REI4 | PHI5 | Notes |
| Vydate C-LV oxamyl | 1A | G | 2.1 pt | 48 h | 7 d | Apply the first foliar treatment of 2.1 pints/A via chemigation at crop emergence. Follow with three applications of 2.1 pints/A on 14-day intervals. Stubby root nematodes must be suppressed prior to tuber initiation to control corky ringspot. |
1Mode of action. NC = not classified..
2 Efficacy ratings denote the relative ability of a pesticide to control its target. The ratings are E = excellent, G = good, F = fair/suppression; P = poor, and ND = no data. Efficacy ratings are based on the inherent toxicity of the pesticide against its target, the likelihood that the target will contact or ingest the product as applied, duration of impact on the target, and undesired effects, such as negative impacts on natural enemies that could lead to future pest outbreaks.
3 Rate per acre per application. Refer to the product label for maximum use rate per season.
4 Reentry interval.
5The minimum pre-harvest interval. Some products do not list PHI.
Note: always read and follow the directions on the pesticide label.
| Stage of Development: Fall Field Preparation | ||||||
|---|---|---|---|---|---|---|
| Pesticide | MOA1 | Efficacy2 | Rate per Acre3 | REI4 | PHI5 | Notes |
| Telone II dichloropropene | 11 | E-G | 20-25 gal | 5 d | Use 20 gal/A for mineral soil or 25 gal/A for muck. Shank-in at 18-inch depth or more. Soil temperature must be between 40°F and 80°F. | |
1Mode of action. NC = not classified..
2 Efficacy ratings denote the relative ability of a pesticide to control its target. The ratings are E = excellent, G = good, F = fair/suppression; P = poor, and ND = no data. Efficacy ratings are based on the inherent toxicity of the pesticide against its target, the likelihood that the target will contact or ingest the product as applied, duration of impact on the target, and undesired effects, such as negative impacts on natural enemies that could lead to future pest outbreaks.
3 Rate per acre per application. Refer to the product label for maximum use rate per season.
4 Reentry interval.
5The minimum pre-harvest interval. Some products do not list PHI.
Note: always read and follow the directions on the pesticide label.
| Stage of Development: Preplant | ||||||
|---|---|---|---|---|---|---|
| Pesticide | MOA1 | Efficacy2 | Rate per Acre3 | REI4 | PHI5 | Notes |
| Telone II dichloropropene | 11 | E-G | 20-25 gal | 5 d | Use 20 gal/A for mineral soil or 25 gal/A for muck. Shank-in at 18-inch depth or more. Soil temperature must be between 40°F and 80°F. | |
1Mode of action. NC = not classified..
2 Efficacy ratings denote the relative ability of a pesticide to control its target. The ratings are E = excellent, G = good, F = fair/suppression; P = poor, and ND = no data. Efficacy ratings are based on the inherent toxicity of the pesticide against its target, the likelihood that the target will contact or ingest the product as applied, duration of impact on the target, and undesired effects, such as negative impacts on natural enemies that could lead to future pest outbreaks.
3 Rate per acre per application. Refer to the product label for maximum use rate per season.
4 Reentry interval.
5The minimum pre-harvest interval. Some products do not list PHI.
Note: always read and follow the directions on the pesticide label.
