Description of the Pest
Several species of leafhoppers are found in dry beans, with Empoasca fabae and E. solana being the most common. They are nearly identical morphologically and can only be distinguished by experts. The damage they cause and the treatment guidelines are also nearly identical.
Empoasca leafhoppers are about 0.125 inch (3 mm) long, bright green, wedge-shaped insects. The wingless nymphs (immatures) are also wedge shaped and green. Nymphs can move forward, backward, and side-to-side very quickly when disturbed. Both adults and nymphs are found primarily on the underside of leaves.
Damage
Empoasca leafhoppers pierce plant tissue, suck plant sap, and inject a toxin. This causes a symptom known as hopperburn in which the leaf margins turn yellow, particularly at the leaf tip, followed by necrosis. The entire leaf may turn yellow, resembling many virus or nutrient deficiency symptoms. Leaves may curl down, especially in blackeyes. The presence of adult and immature leafhoppers on the underside of leaves can distinguish leafhopper injury from virus symptoms or nutrient deficiencies.
Management
Start inspecting plants for leafhopper damage during the vegetative growth stage. Often damage may start on one side of a field as an edge effect. Continue monitoring through the flower bud-to-bloom and pod fill stages. Look for plant damage and Empoasca leafhoppers on the undersides of leaves. Examine a minimum of 10 leaves from 10 plants in at least four areas of the field. Measurable thresholds are not available.
| Common name | Amount per acre** | REI‡ | PHI‡ | |
|---|---|---|---|---|
| (Example trade name) | (hours) | (days) | ||
| Not all registered pesticides are listed. The following are ranked with the pesticides having the greatest IPM value listed first—the most effective and least harmful to natural enemies, honey bees , and the environment are at the top of the table. When choosing a pesticide, consider information relating to air and water quality, resistance management, and the pesticide's properties and application timing. Always read the label of the product being used. | ||||
| A. | FLUPYRADIFURONE | 7–10.5 fl oz | 12 | 7 |
| (Sivanto Prime) | ||||
| MODE-OF-ACTION GROUP NUMBER1: 4D | ||||
| B. | DIMETHOATE | |||
| (Dimethoate 2.67) | 0.75–1.5 pt | 48 | 0 | |
| MODE-OF-ACTION GROUP NUMBER1: 1B | ||||
| COMMENTS: Do not feed sprayed vines to livestock. Not registered for use on cowpea. | ||||
| C. | BIFENTHRIN/IMIDACLOPRID | |||
| (Brigadier) | 3.8–5.6 fl oz | 12 | 14 | |
| MODE-OF-ACTION GROUP NUMBER1: 3A/4A | ||||
| COMMENTS: Review and follow the California neonicotinoid regulations effective January 1, 2024. Permissible application rates of this insecticide may be lower than label rates if applying more than one neonicotinoid active ingredients or using more than one application method in the same season. | ||||
| D. | IMIDACLOPRID | |||
| (Admire Pro) | 7–10.5 fl oz (soil), 1.2 fl oz (foliar) | 12 | 21 (soil), 7 (foliar) | |
| MODE-OF-ACTION GROUP NUMBER1: 4A | ||||
| COMMENTS: Review and follow the California neonicotinoid regulations effective January 1, 2024. Permissible application rates of this insecticide may be lower than label rates if applying more than one neonicotinoid active ingredients or using more than one application method in the same season. | ||||
| E. | LAMBDA-CYHALOTHRIN | |||
| (Warrior II with Zeon) | 1.28–1.92 fl oz | 24 | 21 | |
| MODE-OF-ACTION GROUP NUMBER1: 3A | ||||
| COMMENTS: Do not graze livestock in treated areas or harvest vines for forage or hay. | ||||
| F. | ZETA-CYPERMETHRIN | |||
| (Mustang Maxx) | 2.72–4.0 fl oz | 12 | 21 | |
| MODE-OF-ACTION GROUP NUMBER1: 3A | ||||
| G. | BETA-CYFLUTHRIN | |||
| (Baythroid XL) | 0.8–1.6 fl oz | 12 | 7 | |
| MODE-OF-ACTION GROUP NUMBER1: 3A | ||||
| H. | BIFENTHRIN | |||
| (Bifenture EC) | 1.6–6.4 fl oz | 12 | 14 | |
| MODE-OF-ACTION GROUP NUMBER1: 3A | ||||
| ** | Mix with sufficient water to obtain full coverage. |
| ‡ | Restricted entry interval (REI) is the number of hours (unless otherwise noted) from treatment until the treated area can be safely entered without protective clothing. Preharvest interval (PHI) is the number of days from treatment to harvest. In some cases, the REI exceeds the PHI. The longer of two intervals is the minimum time that must elapse before harvest. |
| 1 | Rotate pesticides with a different mode-of-action group number, and do not use products with the same mode-of-action group number more than twice per season to help prevent the development of resistance. For example, the organophosphates have a group number of 1B; pesticides with a 1B group number should be alternated with pesticides that have a group number other than 1B. Mode-of-action group numbers are assigned by IRAC (Insecticide Resistance Action Committee). |