Cotton fleahoppers (Pseudatomoscelis seriatus) are small plant-feeding insects that are significant pests in cotton production. These insects feed on developing buds and squares, causing them to drop prematurely. This early-season damage can have a major impact on crop yield, making fleahoppers an important pest for growers to monitor and manage.
Fleahoppers are particularly problematic during the early stages of cotton development when plants are producing their first fruiting structures. Because these structures are essential for yield, damage at this stage can result in significant economic losses.
These pests are highly mobile and can move between host plants, including weeds and other crops. This mobility allows populations to build quickly and spread across fields.
The “Square-Dropping” Hemipteran: Cotton Fleahopper
The Cotton Fleahopper (Pseudatomoscelis seriatus) is a high-priority agricultural pest found throughout the Southern United States, particularly in the Texas Cotton Belt. This insect is a critical threat during the 100% early squaring stage of cotton growth. Its feeding on young flower buds (squares) causes them to abort and drop, which can delay the harvest and reduce the final yield of the crop.
Technical Identification: Diagnostic Markers
- Phenotype (Adult): Characterized by an oval, flattened, light-green body (approx. 3mm). A primary diagnostic key is the minute black spots covering the upper surface and the four black spots on the rear margin of the forewings.
- Nymph Phenotype: The nymphs resemble the adults but are wingless and paler green. They possess prominent red eyes and are highly active, moving with a rapid, scurrying gait when disturbed.
- Host Transition: In the United States, they overwinter as eggs in native weeds like horsemint and woolly croton. As these weeds dry out, the fleahoppers migrate to young cotton fields.
Infestation Impact: Square Abortion and Terminal Distortion
The primary impact of the Cotton Fleahopper is the injection of digestive enzymes into tender plant tissue and the loss of early fruiting bodies.
- Blast and Drop: As fleahoppers pierce the young squares to feed, the plant reacts to the salivary enzymes by forming an abscission layer. This severs the bud, causing it to turn brown and drop (blasting).
- Terminal Damage: Feeding on the terminal bud can destroy the apical dominance of the plant. This results in crazy cotton, characterized by excessive vegetative branching and reduced fruit set.
- Economic Threshold: A loss of more than 10-15% of early squares indicates a critical need for national management intervention.
Management & Control Strategies
Management of Cotton Fleahoppers in U.S. cotton production focuses on weed sanitation and precise population monitoring.
| Strategy | Technical Specification | Operational Benefit |
|---|---|---|
| Vegetation Management | 100% Eliminating alternative hosts (Croton/Horsemint) near fields | Removes the overwintering reservoir; prevents the migration into cotton crops. |
| Visual Plant Inspection | Checking terminal buds of 100 plants per field | Provides accurate population density data; prevents unnecessary chemical use.. |
| Biological Conservation | Protecting Big-eyed bugs and Spiders | These national predators provide biological suppression of nymphs; helps maintain ecosystem balance. |
- Monitoring: Use a beat cloth or sweep net during the first three weeks of squaring. Finding 15 to 25 fleahoppers per 100 plants justifies a management action
- Technical Tip: Once the U.S. cotton plant has successfully set its early bolls, it becomes less susceptible to “noxious” fleahopper damage. Early-season vigilance is the key to protecting yield potential.
Identification
Adults are small, pale green insects about 1/8 inch long. They move quickly and may jump when disturbed.
Nymphs resemble smaller versions of adults but lack wings.
Signs include square drop, damaged buds, and reduced fruiting.
Life Cycle
Eggs are laid on host plants. Nymphs feed and develop before becoming adults.
Multiple generations occur each growing season.
Damage and Impact
Feeding causes buds to drop, reducing yield potential. Early infestations are especially damaging.
Crop losses can be significant if populations are not controlled.
Prevention and Control
Monitoring populations is essential. Managing weeds reduces alternate hosts.
Targeted treatments may be used when thresholds are reached.
An Integrated Pest Management approach is recommended.