Phylum Arthropoda K1 2009

Phylum Arthropoda• Kelas Insecta - jumlah spesies sangat bervariasi - jumlah individu sangat melimpah

- penyebaran sangat luas (di

seluruh dunia)

• Kelas Arachnida : - laba-laba - tungau

• Class Crustacea : jenis udang

• Dll. (centipedes, millipedes, etc.)

Insects vs Arachnids (Mites, Spiders)

Siklus hidup serangga• 1. Metamorfosis sederhana /tidak sempurna : telur – nimfa – imago(dewasa)

• 2. Metamorfosais sempurna : telur – larva- pupa – imago(dewasa)

• 3. Some exceptions• #1 and #2 apply to most agricultural pests

Simple MetamorphosisEgg

Nymphs Adult – has full-size wings, functional reproductive system

Simple MetamorphosisNymphs

InstarInstar

Molt Molt

Simple MetamorphosisEgg

Nymphs Adult – has full-size wings, functional reproductive system

Usually 4-6 instars, resemble adults, smaller size

Same food and environment for nymphs and adults

Complete Metamorphosis

Egg Pupa

Larva – several instars, important feeding stage

Adult – very different from larva

Corn Earworm

Complete Metamorphosis• Life stages are important because ecology, food habits, and management of different stages can be different

• Example: butterflies and moths• Larva – feeds as damaging caterpillar

• Adult – beneficial as plant pollinator

Hubungan tanaman dengan serangga

• Hama (Herbivora)• Recyclers of Organic Materials ( pengurai/ dekomposer)

• Predators, parasites• Pollinators (penyerbuk)

Serangga Herbivora• Apabila secara ekonomi menimbulkan kerugian status HAMA

• Dijumpai berbagai jenis kerusakan : akar, batang, daun, bunga, buah bahkan sampai bahan yang disimpan

HAMA

AKAR : Lundi (Exopholis sp)

BATANG : Penggerek batang kakao (Zeuzera sp.)

Daun : Ulat api (Setora nitens)

Bunga : Heliothis armigera

Buah : Lalat buah (Dacus spp.)

Simpanan : Tribolium sp.

Serangga Detritivora• Serangga yang menguraikan zat organik menjadi senyawa karbon yang lebih sederhana.

• Contoh : Rayap Colembola

Kumbang tanah Kumbang bangkai dll.

Serangga Penyerbuk• Hubungan serangga penyerbuk ini dengan tumbuhan SALING MENGUNTUNGKAN

• Hubungan : - mutualisme - komensalisme - parasitisme

Serangga Karnivora• Karnivora

Karnivora

Predator Parasitoid

PREDATOR

- Membunuh & memangsa banyak hewan dalam satu siklus hidupnya

- Ukuran lebih besar daripada mangsanya

PARASITOID• Parasitoid : serangga yang menumpang pada serangga lain yang menyebabkan kerugian pada inangnya

• Biasanya setiap individu serangga parasitoid hanya memerlukan satu ekor inang dalam satu siklus hidupnya.

Survey of insects – Major groups (orders) of ag pests

or beneficials• Dragonflies• Orthoptera and relatives (mantids, roaches)

• Thrips• True bugs (Hemiptera)• Piercing-sucking insects (Homoptera)• Beetles• Nerve-winged insects (Neuroptera)• Butterflies and moths• Bees, wasps, and ants• Flies• Etc.

Survey of Insects• Dragonflies --- beneficial predators of flying insects

• Praying mantids --- beneficial predators

• Roaches --- recycling in some ag systems

• Grasshoppers, Crickets --- can be serious ag pests

Tawny Mole Cricket

Thrips

Thrips palmi

Thrips• Almost microscopic in size, fringed wings

• Beneficial pollination in flowers

• Most are plant pests• Some carry plant viruses

Virus Vectors• Vector = carrier of virus• Viruses in plants• Transmitted by insects, etc.• Vector feeds on infected plant acquires virus feeds and passes virus to other plants

True Bugs

• Squash bug• Note typical appearance

True Bugs• Piercing-sucking mouthparts• Some important pests, e.g., stink bugs

• Some predators