Post on 24-May-2018
transcript
Entomology For Master
Gardeners
Molly Greenwood
Spring 2017
Extent and Economic Importance
○ Major form of higher life
○ Attack all stages of all species
○ Damage equals harvest
○ Beneficial aspects
Beneficial Aspects○ Pollination
○ Predators / Parasites
○ Human food
○ Biological control agents
○ Nutrient recycling
○ Insect products: honey, wax, shellac, dye
○ Conservation biology
○ Art and literature
○ Ecotourism- butterfly farms / exhibits
Population Dynamics○ Insects have high reproductive potential
○ Can migrate; move with plants
○ Population limited by:
○ Environmental resistance
○ Host plant resistance
○ “if you build it, they will come”
○ Exotic (non-native) insects
Movement and Spread○ Adults have wings & legs
○ Adults can migrate
○ Larvae have legs
○ Larvae can walk
○ Larvae can move with wind
Concept of a Pest○ Interfere with objectives
○ Insects play vital ecological roles
○ 1% of insects are pests
○ Learn to live with damage- economic threshold
Diagnosing Insect Pest Problems
○ Recognize limitations
○ Most “sick” plants are abiotic
○ Identify the plant
○ Note the symptoms
○ Look for broad patterns
○ Within plant (leaf vs. fruit)
○ Across plant (spot vs. all plants)
○ Collect specimens
Pest Managment○ Integrated Pest Management
○ Legislative Control
○ Physical/Mechanical Control
○ Cultural Control
○ Biological Control
○ Chemical Control
IPM○ Integrate all approaches to manage pest
○ Pest ID
○ Detection, monitoring models
○ Know insect biology
○ Ecologically sound
Legislative Control○ Quarantine
○ State regulation- noxious weeds
○ Public education critical
Physical Control○ Insect removal/habitat destruction
○ Sanitation/salvage
○ Firewood in direct sun
○ Physical barriers- cutworms
○ Mass trapping
○ Trap trees
Cultural Control○ Crop rotation
○ Green manure fallow
○ Genetic resistance
○ Conventional resistant varieties
○ GMO’s
Biological Control○ Ecologically best strategy
○ Life history knowledge critical○ Classical vs. Bio. insect pest suppression○ Bio control agents
○ Vertebrate predators
○ Invertebrate predators
○ Invertebrate parasites
○ Pathogenic microorganisms ○ Ex. Virus, bacteria (Bt), fungi, nematodes
Chemical Control○ Limitations: ecological, cost, hazard
○ Follow label-legal document
○ Pay attention to pre-harvest interval
○ Federal regulation of residual tolerance
○ Pesticide applicator certification
Characteristics of Insects○ Arthropods: exoskeleton, jointed appendages
○ Adult Insects:
○ Head, thorax, abdomen
○ 1pair antennae
○ 3 pair legs
○ 2 pair of wings Head
Thorax
Abdomen
1. Head:
Sensory Organa) Paired appendages
(antennae)b) Mouthparts
2. Thorax:
Locomotion
3. Abdomen:
Reproductive and Digestive
Arthropods (Phylum Arthropoda: also include trilobites, horseshoe crabs,
spiders, crustaceans, millipedes, centipedes)Insects are all in the HEXAPODA (class)
Body with three distinct regions: head, thorax, and abdomen
Head
Thorax
Abdomen
Insect Classification
Insect Classification
Insect Classification
Taxonomic Classification○ Common level: Order and Family
○ Basis for classification
○ Mouthparts
○ Type of wings
○ Type of metamorphosis
• Prolegs
• Thoracic legs
Prolegs
Thoracic legs
Insect Relatives○ Spiders, mites, ticks, centipedes, millipedes,
sowbugs, snails, slugs
○ Bugs vs. “bugs”
Insect Growth and Development
○ Metamorphosis
○ Shed exoskeleton (molting)
○ Stages
○ Egg
○ Larva/nymph
○ Pupa
○ Adult
○ Instars
○ Metamorphosis
Insect Growth and Development
○ Gradual: ○ Egg-nymph-adult
○ Nymph similar to adult
○ Ex. Aphids, scales, grasshoppers
○ Complete:○ Egg-larva-pupa-adult
○ Larva does damage
○ Stages occur in different habitats
○ Ex. Beetles, butterflies, flies
Insect Feeding/Mouthparts○ Chewing
○ Hard mandibles
○ Holes, tunnels, partial eaten leaves
○ Sucking
○ Straw (stylet), probosis
○ Curling, stunting, mottling, galls
○ Phytotoxic necrosis
Piercing/sopping
Common Insect Orders○ Coleoptera: beetles, weevils
○ Dermaptera: earwigs
○ Diptera: flies, mosquitoes, gnats, midges
○ Hemiptera: true bugs
○ Homoptera: aphids, scales, leafhoppers, cicadas, whiteflies, mealy bugs
○ Hymenoptera: bees, wasps, ants, sawflies
○ Isoptera: termites
Coleoptera: beetles, weevils
Attributes: 400,000 species, hard front wings, beneficial and pest species, adults and larvae may feed on same host
Complete Chewing
Dermaptera: earwigs
Attributes: front wings thickened, pest or beneficial (aphid predator), nocturnal, hide during the day
Gradual Chewing
Diptera: flies, mosquitoes
Attributes: larvae legless, adults soft bodied, compound eye, one pair of wings, haltere, disease vectors, pest and beneficial
Complete Larvae: chewing/hooksAdult: sponging, piercing
Hemiptera: true bugs
Attributes: nymphs resemble adults, many plant feeding pests, triangle on back, some predators, some disease vectors (Chagas disease)
Gradual Piercing, sucking
Homoptera: aphids, leaf hoppers, white flies, scales
Attributes: small soft bodied insects, unwinged forms, attack many vegetables, multiple generations, parthenogenesis, some disease vectors (CTV), greenhouse pests
Gradual Sucking
Hymenoptera: bees, wasps, ants, sawflies
Attributes: legless larvae, adult stinger, two pair of membranous wings, ants with narrow waist, many species, pollinators, parasites, predators, sawflies are important defoliators, many species social
Complete Chewing
Isoptera: termites
Attributes: soft bodied insects, winged or wingless, colonies occur in ground or in wood, drywood and subterranean termites, caste system, social
Gradual Chewing
Lepidoptera: moths, butterflies
Attributes: caterpillars, adults have two pairs of scaled wings, many defoliators, adults feed on nectar, adults pollinate, basis for ecotourism
Complete Larvae: chewing Adults: sucking
Neuroptera: lacewings, antlions
Attributes: adults have 2 pairs of membranous wings, wings held rooflike, many species are predators
Complete Chewing
Orthoptera: grasshoppers, crickets, mantids, cockroaches
Attributes: hard bodied adult, two pair of wings, front wings are hard, adults and nymphs cause damage, moderate pests
Gradual Chewing
Siphonaptera: fleas
Attributes: wingless insects, live as ectoparasites on birds and mammals, body is laterally flattened, often jumping, important disease vectors, include plague and typhus
Complete Sucking
Thysanoptera: thrips
Attributes: adults are minute soft bodied, two pairs of long wings, many feed on plants and especially flowers, cause cosmetic damage to fruit, some disease transmission
Gradual Sucking
Common Insect Orders Continued
○ Lepidoptera: moths, butterflies
○ Neuroptera: lacewings, antlions
○ Odonata: dragonflies, damselflies
○ Orthoptera: grasshoppers, crickets, mantids, cockroaches
○ Siphonaptera: fleas
○ Thysanoptera: thrips
○ Thysanura: siverfish, firebrats