Identifying and managing plant pest in fruit and vegtables 1

What insect and disease pests affect the growth of fruits and vegetables?. What insect and disease pests affect the growth of fruits and vegetables?. What insect and disease pests affect

Horticulture Science

Lesson 39

Identifying and Managing Plant Pests in

Fruits and Vegetables

Interest Approach

Ask students to describe the “perfect” apple What characteristics do they look for when picking an apple? After students list these traits, ask them to tell you the things that can make an apple undesirable What causes these undesirable characteristics?

Student Learning Objectives

•Identify insect and disease pests of fruits and vegetables.

•Analyze methods of pest management for

fruits and vegetables.

What insect and disease pests affect the growth of

fruits and vegetables?

• Like any other crops, fruits and vegetables have pests

• These pests can impair fruit or vegetable growth and

production

• Damage to fruits and vegetables can be enough to leave

them worthless to the grower.

• Hundreds of insects affect the growth and yield of fruit and vegetable crops.

What insect and disease pests affect the growth of

fruits and vegetables?

• These pests can cause damage in a number of different ways

– The most obvious way insects can affect plants is by

consuming the foliage or fruit

– Result in poor quality and contamination of the edible parts

of the fruit or vegetable crop

– Insects can also do damage by piercing plants and sucking

nutrients from them

– Insects also spread disease

– The consumer generally does not tolerate the presence of

insects on or in fruits or vegetables

– Most products must be free of insect pests to be marketable

What insect and disease pests affect the growth of

fruits and vegetables?

1 Aphids are pear-shaped, soft-bodied, usually

wingless insects

– They are often green or yellowish in color

– Aphids have the ability to reproduce very rapidly

– Astonishingly, they give birth to live young that are born

What insect and disease pests affect the growth of

fruits and vegetables?

2 Cabbage worms attack cabbage, broccoli, lettuce,

and other related crops.

– They are 1-inch-long green cabbage looper or butterfly

larvae

– They eat holes in the leaves and flowers

What insect and disease pests affect the growth of

fruits and vegetables?

3 The Colorado potato beetle is a yellowish

½-inch-long beetle with brown stripes

– It eats potatoes, peppers, tomatoes, and eggplant

What insect and disease pests affect the growth of

fruits and vegetables?

4 Cucumber beetles eat holes in the leaves of

cucumbers, melons, and squash

– They are about ¼ inch in size

– Their bodies are yellowish with black stripes

– They also carry cucurbit wilt disease

What insect and disease pests affect the growth of

fruits and vegetables?

5 The corn earworm is a

What insect and disease pests affect the growth of

fruits and vegetables?

6 The peach tree borer attacks stone tree fruit,

including peaches, plums, nectarines, apricots, and

cherries

– It damages the inner bark from about 12 inches above the

ground to about 3 inches below the ground

– Serious infestations cause individual branches or entire trees

to die

What insect and disease pests affect the growth of

fruits and vegetables?

7 The apple maggot infests apples, plums, and

blueberries

– The adult fly emerges between June and September

– It lays an egg inside the skin of a developing fruit

– The larva tunnels through the flesh of the fruit

What insect and disease pests affect the growth of

fruits and vegetables?

8 The San Jose scale is a pest of apples, pears, peaches,

apricots, plums, and cherries

– The scale feeds on branches, leaves, and fruit

– Infested fruit drops, branches lose vigor and die, and leaves and fruit have a red spotted appearance

What insect and disease pests affect the growth of

fruits and vegetables?

9 The codling moth is a serious pest of the apple

– The larva damages the apple by burrowing into the center of the fruit

– As the larva chews its way inward, it pushes fecal material

through the opening

What insect and disease pests affect the growth of

fruits and vegetables?

10 Plum curculios attack apples, peaches, pears,

plums, and cherries

– Larvae tunnel through the fruit and cause the fruit to drop or rot

What insect and disease pests affect the growth of

fruits and vegetables?

• There are three main causes of fruit and vegetable

diseases

• The pathogens that cause plant disease are fungi,

bacteria, and viruses

• For one of these pathogens to infect a plant, the

environmental conditions must be right, the host plant

must be susceptible, and the pathogen, or the cause of

disease, must be present.

What insect and disease pests affect the growth of

fruits and vegetables?

1 Root and stem rots are caused mostly by Pythium,

Phytophthora, Rhizoctonia, and Fusarium fungi

– When plant roots and stems rot, plant growth becomes

stunted, and the plant wilts easily

– Pythium is one fungus that can cause damping-off

– Damping-off is the early death of seedlings that have

germinated

– More mature plants can also develop root and stem rots as a

result of Pythium, particularly when the growing medium has

poor aeration

– Rhizoctonia causes damping-off, as well as root and stem

rots

What insect and disease pests affect the growth of

fruits and vegetables?

2 Aster yellows is a viral disease of brambles and other

What insect and disease pests affect the growth of

fruits and vegetables?

3 Rusts are fungal diseases of apple, hawthorn, juniper,

and other species.

– Symptoms of rust are bright yellow, orange, orange-red,

reddish-brown, darkbrown, or black powdery raised pustules

on leaves, stems, and fruit

– Leaves may wither and die, and plants may be stunted

What insect and disease pests affect the growth of

fruits and vegetables?

4 Scab is a fungal disease common to crab apples and

apples, but other species are also affected

– Initially, small light brown to olive-green lesions appear on the undersides of leaves

– The spots turn black; the leaves may curl; and if the petioles are infected, the leaves drop

What insect and disease pests affect the growth of

fruits and vegetables?

5 Leaf spots and blights are caused by fungi and

bacteria

– They are common with many vegetables and fruits

– Most leaf spot diseases appear as small, scattered, round to oval dead areas

– The appearance of the lesions varies

What insect and disease pests affect the growth of

fruits and vegetables?

6 Cankers have a variety of causal agents

– A canker is a localized dead area in the cambium and bark of

a branch or trunk

– Cankers may appear sunken, flat, or swollen

– They are typically discolored

– Cankers can enlarge and girdle the stem, resulting in the

death of all tissue beyond the infection

What insect and disease pests affect the growth of

fruits and vegetables?

7 Fireblight is a disease of plants in the rose family,

including apples, pears, and quince

– It is caused by a bacterium

– Flowers, shoots, and branches may be attacked

– Symptoms are leaves that wilt and turn brown, giving the

plant a scorched look

What insect and disease pests affect the growth of

fruits and vegetables?

8 Verticillium wilt is caused by fungi

– It is a vascular disease that infects both woody and

herbaceous plant species

– Leaves on a branch wilt and turn brown, and individual

branches die back

– The sapwood is discolored and has a dark streaking

What insect and disease pests affect the growth of

fruits and vegetables?

9 Botrytis blight is a fungal disease that can attack fruit

crops

– It causes a brown rotting and develops fuzzy, gray mold as it produces spores

– Botrytis is most common when temperatures are between

60° and 70°F, air circulation is poor, and humidity is high

What insect and disease pests affect the growth of

fruits and vegetables?

10 Brown rot is a fungal disease that infects ripening

peaches, nectarines, plums, cherries, and apricots

– Rotted areas are soft and brown

– Blossoms and shoots may also wilt and turn brown

What insect and disease pests affect the growth of

fruits and vegetables?

Slugs are brown to black shell-less snails ranging from ½

inch to more than 1 inch long

– Slugs feed on leaves, flowers, and fruit during the night

Mice and voles are serious pests of apples

– The animals chew the roots, as well as the bark on the trunk

of a tree

– Badly damaged trees die

What methods of pest management are used for

fruits and vegetables?

• Insects, diseases, and weeds can be managed to reduce losses to fruits and vegetables.

• There are a number of general practices that are

employed to manage insect and disease pest problems.

1 Select and grow disease-resistant varieties and

hybrids.

2 Use seed treated with a fungicide to reduce

damping-off.

3 Examine the plants for signs of disease or insect

infestation and address the problem promptly.

What methods of pest management are used for

fruits and vegetables?

• 4 Fertilize the plants properly to promote healthy

growth.

• 5 Use attractant baits to manage slug and snail

populations.

• 6 Mulch the plants to reduce soilborne diseases,

reduce weed problems, and maintain uniform soil

moisture.

• 7 Avoid working in the garden when the plants are wet

– Moisture contributes to the spread of disease

What methods of pest management are used for

fruits and vegetables?

• 8 Remove plant residue that has been infected with

disease and dispose of it.

• 9 Rotate the crops in the garden every year and avoid planting the same type of vegetable in the same

location more than once every three years.

• 10 Eliminate weeds from around fruits and vegetables

– They harbor insects and diseases

– They also compete for nutrients, water, and light

What methods of pest management are used for

fruits and vegetables?

• 11 Remove dead and diseased limbs from fruit trees

– Proper pruning can increase light penetration to the foliage and inhibit disease development

– It can also improve air circulation, thus reducing diseases

• 12 Apply chemical pesticides to manage existing pests when other control methods have failed.

•What insect and disease pests affect the

growth of fruits and vegetables?

•What methods of pest management are used for fruits and vegetables?