Common Pests in Agriculture: Identification and Control
Common Agricultural Pests
Arthropods grow by molting, eliminating the old cuticle and replacing it with a larger one.
Parasitic Arthropods
| Etiologic Agent | Pulicosis | Scabies | Pediculosis |
|---|---|---|---|
| Etiologic Agent | Pulex irritans (flea) | Sarcoptes scabiei (scabies mite) | Pediculus humanus (louse) |
| Order | Siphonaptera | Mite | Phthiraptera |
| Life Cycle | Egg, larva, pupa, adult | Egg, nymph, adult | Egg, nymph, adult |
| Prevention | Hygiene | Hygiene, stable partners | Hygiene, periodic checks |
| Damage | Transmits bubonic plague | Skin rash, bumps | Itchy scalp |
| Control | Insecticide | Drugs | Treat lice on dry hair |
Scientific Names
- Louse: Pediculus humanus
- Crab louse: Phthirus pubis
- Flea: Pulex irritans
- Brown recluse spider: Loxosceles laeta
- Black widow spider: Latrodectus mactans
- Sytodes globula
Pests of Agricultural Importance in Chile
Damaging Agents
- Disease vectors
- Ecto- or endoparasites
- Inject or deposit toxic substances
- Damage food, cloth, wood, etc.
- Cause nuisance (sound, odor, etc.)
- Damage plants and consumables
- Sap suckers
- Create galleries in roots, stems, leaves, and fruit
- Facilitate pathogen development
- Contaminate stored products
Beneficial Agents
- Produce marketable substances
- Remove organic waste
- Improve soil aeration and add organic matter
- Serve as food for other animals
- Contribute to scientific knowledge and medical treatment
- Pollinate flowers
- Eliminate insect pests
- Destroy weeds
Specific Pest Information
Black Olive Scale (Saissetia oleae)
- Rigid shell with an H-shaped roughness
- Appendix present in immature state
- Parthenogenetic reproduction
- Located in the xylem of the tree
- Feeds on sap
- Excretes honeydew
Fruit Weevil (Pantomorus cervinus)
Adult: Oval, grayish-brown, with ridged elytra. Eggs laid in masses of up to 50, rolled in dried leaves. Larvae are curved, with prominent mouthparts. Found in soil, feeding on roots. Adults bite leaf edges.
Whitefly (Paraleyrodes sp.)
Winged adults covered in white waxy substance. Nymphs have seven pairs of long, stiff wax strands.
Argentine Ant (Linepithema humile)
Small insects (2-3 mm long), reddish-brown with lighter appendages. Do not cause direct plant damage. Feeds on honeydew secreted by pest species, protects pest species from predators.
Hemispherical Scale (Saissetia coffeae)
- Hemispherical, reddish-brown shell
- Smooth and shiny texture
- Located at branch ends
Soft Scale (Coccus hesperidum)
- Slightly convex, oval shape
- Brown or mottled yellow and brown
- Ovoviviparous
- Nymphs are reddish, then almost transparent
Circular Scale (Ceroplastes cirripediformes)
- Oval, convex shape
- Thick, pearl-gray waxy coat with lumps
- 3-5 mm in size
- Oviparous and parthenogenetic
- Juveniles on leaves, then twigs
Pear-shaped Scale (Protopulvinaria pyriformis)
- Triangular, pear-shaped
- Flattened
- Adults yellowish-brown, nymphs almost transparent
- 2.5-3.5 mm in size
- Located on leaf undersides
- All stages present
Mealybug (Pseudococcus calceolariae)
- Oval, reddish-white body
- Moderately abundant waxy powder
- Lateral filaments
- Oviparous
- Eggs in irregular cottony mass
Citrus Mealybug (Planococcus citri)
Female: Oval, covered in white wax, short lateral filaments. Males: Winged. Sexual and parthenogenetic reproduction.
Long-tailed Mealybug (Pseudococcus longispinus)
- Oval body, waxy powder
- Gray dorsal stripe
- Long, thin filaments
- Viviparous
White Cottony Cushion Scale (Aleurothrixus floccosus)
- Winged males and females
- Body covered in white waxy substance
- Females lay eggs on leaf undersides
Green Citrus Aphid (Aphis spiraecola)
Wingless, ovoid, green females (1-2 mm long). Found on young shoots.