KEEPING PLANTS HEALTHY

CHAPTER 10

AGRISCIENCE AND TECHNOLOGY

FIVE MAJOR CATEGORIES OF PESTS

• INSECTS

• NEMATODES

• DISEASES

• WEEDS

• RODENTS

CHARACTERISTICS OF INSECTS

• Insects have three pair of legs.

• Insects body is divided into three sections: head, thorax and abdomen.

• The legs and wings, if any, are on the thorax.

• The abdomen usually has no attachments.

TWO TYPES OF MOUTH PARTS

• CHEWING : Bite off, chew and swallow parts of plants; examples include cutworms, bean beetles and armyworms.

• SUCKING : Suck sap from a plant; examples include aphids, chinch bugs, thrips, squash bugs and leafhoppers.

METAMORPHOSIS FOUR STAGES

• 1. EGG• 2. LARVA• 3. PUPA• 4. ADULT• EXAMPLES OF INSECTS WITH

COMPLETE METAMORPHOSIS INCLUDE MOTHS AND BUTTERFLIES, BEETLES AND BOLL WEEVILS.

INCOMPLETE METAMORPHOSIS

• 1. EGG

• 2. NYMPH

• 3. ADULT

• EXAMPLE IS A GRASSHOPPER

WAYS INSECTS ARE BENEFICIAL

• IMPROVE THE SOIL - Allow air to enter the soil or bury decaying parts of plants: ants,wild bees and beetles.

• HELP POLLINATE PLANTS - Spread pollen from plant to plant: bees, butterflies, wasps and beetles.

• DESTROY INSECTS - Attack and destroy harmful insects: lady beetles, dragon flies, wasps and ants.

NEMATODES

• Nematodes are tiny worm-like organisms that live in the soil and attack the roots and stems of plants.

• Accurate identification requires laboratory testing.

• Nematodes are carriers of certain diseases.

MAJOR TYPES OF PLANT DISEASES

• ENVIRONMENTAL

• 1. Nutrient deficiencies

• 2. Damage to plant parts

• 3. Chemical injuries

• 4. Pollution injuries

• 5. Weather

• 6. Naturally-occurring genetic abnormalities

• PARASITIC• 1. Fungi• 2. Bacteria• 3. Viruses

KINDS OF WEEDS

• ANNUALS - Morning glory, cocklebur, pigweed, crabgrass, chickweed and henbit are examples.

• BIENNIALS - Thistle and wild carrot are two examples.

• PERENNIALS - Dandelion, plantain, bermudagrass, poison ivy and johnsongrass are examples.

PROBLEMS THAT WEEDS CAUSE

• Keep plants from growing

• Waste nutrients

• Lower quality of crop

• Make harvesting harder

• Hiding place for insects and disease

• Look bad

RODENTSEXAMPLES OF DAMAGE

• Deer that eat soybean plants growing in a field.

• Raccoon that climb corn stalks and get roasting ears.

• Rabbits that bit off the tender leaves of new bean plants.

• Birds that eat grain from sorghum• Rats that eat fruit growing near the ground

CONDITIONS NEEDED FOR A PEST TO CAUSE PROBLEMS

• A PEST MUST EXIST

• A SUSCEPTIBLE PLANT

• THE RIGHT ENVIRONMENT

WAYS THAT PESTS DAMAGE PLANTS

• Pests chew holes in plants

• Pests attack the vascular system

• Pests attack the fruit

• Pests contaminate products

• Pests rob plants of food

• Pests damage land

HOW DAMAGE AFFECTS THE PRODUCER

• Reduced yields

• Lower quality

• Increased production costs

• Hiding place for pests

• Restrict Marketing

WAYS TO PREVENT PEST PROBLEMS

• Use good seed• Destroy diseased plants• Use the right fertilizer• Disinfect equipment• Use good water • Control animal movement• Use chemicals properly• Use tests to check for pests

MECHANICAL METHODS OF PEST CONTROL

• PLOWING

• MOWING

• MULCHING

CULTURAL PRACTICES

• ROTATE CROPS

• ROGUING

• TRAP CROPPING

• BURNING

• USE RESISTANT VARIETIES

• CLEAN AROUND FIELDS

PESTICIDES

• Chemicals used to control pest.

• Insecticides - controls insects

• Nematocides - controls nematodes

• Fungicides - controls fungi

• Bactericides - used to control bacteria

• Herbicides - used to control weeds

TYPES OF INSECTICIDES

• STOMACH POISONS - Eaten by the insect• CONTACT POISONS - Absorbed through

the insect’s skin.• SYSTEMIC POISONS - Poison is absorbed

by the plant and when insects bites or sucks its juice, it gets poison.

• FUMIGANTS - Enters the insect’s body through the respiratory system.

TYPES OF HERBICIDES

• SELECTIVE HERBICIDES - Will only kill certain kinds of plants.

• NON-SELECTIVE HERBICIDES - Used to kill all vegetation where they are applied.

• TRANSLOCATED HERBICIDES - Absorbed into the plant and moved all through its parts; upset the growth process of weeds.

NON-CHEMICAL MEANS OF CONTROLLING PESTS

• BIOLOGICAL PEST CONTROL - Using living organisms to control pests.

• GENETIC METHODS - Develop crops that are resistant to pests

IPM

• Integrated pest management is a planned process for controlling pests.

• Involves using a blend of pest control techniques in a planned program.

• Field of crops is managed as an ecosystem.

• IPM has fewer adverse effects on the environment.

SAFETY PRACTICES IN PEST CONTROL

• Use only approved pesticides

• Know the pesticide

• Use the pesticide with low toxicity

• Use pesticides only when needed

• Do not contaminate resources

• Wear protective clothing

SAFETY PRACTICES IN PEST CONTROL

• Wash the skin after contact

• Dispose of empty containers properly

• Apply in good weather

• Use the right equipment

• Know the emergency measures