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DO NOW. So far in our green house we have encountered two different pests. Describe the two and how did we get rid of them?. Mealy Bug. Aphids. Spider Mite. Potato Beetle. You are a farmer and have an infestation of pests eating your crops.
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DO NOW So far in our green house we have encountered two different pests. Describe the two and how did we get rid of them?
Mealy Bug Aphids Spider Mite Potato Beetle
You are a farmer and have an infestation of pests eating your crops. • Which are some means that you might use to save your crop?
Possibilities? • a) chemicals • b) go into the field and start killing the pests manually • c) used their predators to get rid of them
Which kinds of things can a farmer do on a regular basis to catch pests early on?
If the plants are inspected on a regular basis then the number of pests can be controlled. • First control should be nonchemical
Aim: How can farmers get rid of their pests through nonchemical means?
Which is an advantage of using nonchemical means for the removal of pests? • Turn and talk: You know you would like to get rid of your pest but do not want to use chemicals. Name some possibilities.
a) hand collect pests (killing them manually) • b) pruning off diseased limbs • c) biological control
Biological Control • Explain how you think biological control works. • Hint, you know that it does not involve the use of any kinds of chemicals.
Biological Control • Use of a natural enemy of a pest to control its population • Ex: Braconid wasps lay their eggs on the larval (baby) tomato hornworm • The European seven spotted lady beetle eats aphids • Once established, the natural enemy will keep doing its job year after year.
Which might be some possible drawback in using biological control?
Draw Back • The pest control agent must be present in large numbers to be effective • Many brought to where they are needed from places where they are bred in large numbers • You can’t erradicate the pest, not 100% effective. • However it’s good enough. Farmers deal with minor losses.
Disease and insect resistant plants • Many varieties are made so that they are so poisonous to the pest no chemicals are needed. • Better boy tomatos are VFN resistant • Find out what the VFN stands for as HW
Imagine you are a pea aphid As a pea aphid, you can only feed off pea plants. • You have two options, land in a field of pea plants or land in a field with all sorts of crops some of which are pea plants. • Which field would you land on?
How would you use crop rotation and other planting methods to control pests?
Growing multiple types of crops reduces your losses, and reduces the numbers of any one pest • Pests that can’t travel far can only infest one patch of a particular crop if the same types of crops are not planted together. • And pests like fungus or worms that don’t travel can be stopped if farmers don’t grow the same crop in the same place every year
Mealy Bugs • Mealy bugs have small soft white or pink bodies. In addition, they secrete a fluffy white wax which makes the plant leaf or stem look as if tiny bits of cotton are stuck to it. Infected leaves may be covered with small white spots.
Scale insect • Scale are harder to find on a plant. Many look like little bumps on the plant, and you may not realize they are not part of the plant itself. They tend to cluster together on twigs and leaf midveins. Infected plants may develop spotted leaves, branchs dieback, and leaf drop.
Many many different species of scale Adult males have wings and fly around looking for females
Spider mites • Spider mites pierce the plant leaf to extract sap, causing tiny yellow spots on infected leaves. Many spider mites are tiny red mites which are difficult to see without a magnifying glass. Infested plants will develop a bronzed look. The leaves turn brown and fall off. • Spider mites also spin a small webbing on shoot tips and leaf axils.
Whiteflies • Plants infested with whiteflies become yellow and sickly. The leaves show cupping and slower growth. When an infected plant is brushed or moved, the winged adults are easily seen as they fly around. They resemble tiny winged moths.
Aphids • Aphids cluster at the end of new shoots on flower buds, and on the undersides of leaves. • Aphids may be light green, red or black in color. They cause stunted, distorted leaves and plants that grow slowly. • Many aphids are resistant to pesticides. To control a very mild infestation, spray warm soapy water directly on the insects, and then remove the soap with plain water. Destroy heavily infested plants.
Fungus Gnats • The hatched offspring of tiny black flies. The larvae attack plant roots.
Summary: explain what biological control means • HW: read pages 159 -172pages 172 and 173 do 1-10 and 10 B • Due after Christmas vacation • Read The Birds of Killingsworth by Henry Wadsworth Longfellow • What happened to the birds of Killingsworth? • Why were they important biological pest control agents? • What happened to the town’s crops? • http://www.hwlongfellow.org/poems_poem.php?pid=2047