HPIPM:Leafhoppers DB
From BugwoodWiki
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Authors: Gary L. Hein & Frank B. Peairs[1]
  Photo by Steve L. Brown, University of Georgia, Bugwood.org |  Photo by Frank Peairs, Colorado State University, Bugwood.org |
The potato leafhopper, Empoasca fabae (Harris), can be a devastating insect on dry beans; however, the leafhopper does not overwinter in the region and must migrate in from the Gulf Coast region. This does not occur regularly, but because of the potential severity of damage from this insect it is important to be familiar with it.
Identification (and life cycle/seasonal history)
The potato leafhopper can be a serious problem in dry beans early in the season. It overwinters in the Gulf Coast region, and migrates into areas of North America in the spring to establish summer populations. Its migration into the High Plains region usually occurs in too low of numbers and too late in the season to cause serious damage. However, in some years significant migration into the region can occur in June to create serious damage to dry beans. Damage potential decreases from east to west in Nebraska, but severe damage has occurred as far west as the Panhandle. The potato leafhopper is a wedge-shaped, lime-green insect with six white spots just behind the head. The nymphs are also lime green, and are most often found on the underside of the bean leaves. The nymphs are easily recognized because of their unusual habit of walking sideways very rapidly when disturbed.
Plant Response and Damage
The leafhopper injects a toxin during feeding that damages the plant and results in leaf discoloration and stunting. Damaged leaves will turn yellow on the edges and tips, and later these areas of the leaf will die and turn brown. Damaged plants also will be stunted and have short internodes. Plants will be slow to recover from damage and may be stunted for the rest of the season.
Management Approaches
The most serious damage from the potato leafhopper will result when beans are infested at an early growth stage. Sampling the beans from emergence through early July should be done to determine if leafhoppers are present. A sweep net can be used to quickly determine the presence of the leafhoppers in the field. If leafhoppers are present, a more specific sampling of individual plants should be done to determine the density of leafhoppers on the plants. Twenty plants across a field should be examined for the presence of leafhoppers and for the number of trifoliates per plant. On seedling (unifoliate) plants, the threshold for treatment is ½ leafhopper per plant. Later, the threshold for treatment is one leafhopper (including nymphs and adults) per trifoliolate.
Product List for Leafhoppers:
| Insecticide | Product per Acre (fl oz. or oz. product) | Preharvest Interval , remarks |
|---|---|---|
| acephate2 | See labels | PHI 14 days; REI 24 hrs. |
| dimethoate1,2 | See labels | 7 day PHI; REI 48 hrs. Do not feed treated vines. |
| endosulfanR,2 | See labels | PHI 3 days; REI 24 hrs. |
| esfenvalerateR,1,2 | See labels | PHI 21 days; REI 12 hrs. Pea and soybean aphids only. |
| gamma-cyhalothrinR,1 | See labels | PHI 21 days; REI 24 hrs. |
| imidacloprid1,2 | See labels | PHI 21 days; REI 12 hrs. |
| lambda-cyhalothrinR,1 | See labels | PHI 21 days; REI 24 hrs. |
| LannateR,1 LV or SP | 8-16 (SP), 24-48 (LV) | PHI 14 days; REI 48 hrs. |
| Penncap-MR | 32 | PHI 15 days; REI 5 days. |
| Mustang MAX ECR,1 | 3.2-4.0 | PHI 21 days; REI 12 hrs. |
| Temik 15GR | 5.0-7.0 lbs | Apply at planting. Potential for groundwater contamination. See label for environmental precautions and restrictions. PHI 90 days; REI 48 hrs. |
| phorate 20GR,2 | 4.5-7.0 oz/1000 row ft | Apply at planting; drill to side of seed, not in contact with seed; PHI 60 days; REI 72 hrs. |
| Cruiser 5FS | 1.28 fl oz/100 lb seed | See treatment directions and precautions on label. |
| Gaucho 480 | 2-4 fl oz/100 lb seed | See treatment directions and precautions on label. |
| RRestricted use pesticide, 1Labeled for chemigation, 2Generic active ingredient, several formulations. | ||
The information herein is supplied with the understanding that no discrimination is intended and that listing of commercial products, necessary to this guide, implies no endorsement by the authors or the Extension Services of Nebraska, Colorado, Wyoming or Montana. Criticism of products or equipment not listed is neither implied nor intended. Due to constantly changing labels, laws and regulations, the Extension Services can assume no liability for the suggested use of chemicals contained herein. Pesticides must be applied legally complying with all label directions and precautions on the pesticide container and any supplemental labeling and rules of state and federal pesticide regulatory agencies. State rules and regulations and special pesticide use allowances may vary from state to state: contact your State Department of Agriculture for the rules, regulations and allowances applicable in your state and locality.
