How To Control The Garden Pests Aphids
All About Aphids:
To combat an enemy you must first know your enemy. An Aphid is a slow-moving, tiny, soft-bodied insect that comes in a wide variety of colors. Some Aphids can be almost colorless. Aphids have antennae with 4 to 6 segments. Their feeding mouth part is called stylets, which is enclosed in a tiny sheath called a rostrum. Aphids have thin, long legs that have two joints and two claws called tarsi.
Aphids have defensive mechanisms. One such defense is a pair of cornicles, or abdominal tubes which excrete tiny droplets of fast-hardening fluid which contains triacylglycerois, otherwise known as cornicle wax. Other types of aphids can produce other defensive mechanisms.
Aphids have a "sort-of" tail called a cauda above their rectal area. They also have two compound eyes, and an ocular tubercle fixated behind and slightly above each eye which is made up of three lenses.
Sometimes when a plant becomes over-crowed or in poor condition, some aphids will produce a winged offspring called alates, that come fly to other sources of plants and foods.
Aphids are known world-wide, but thrive most in temperate zones. They can travel far distances, usually by passive usage of the wind.
Aphids feed on plants by sucking out all their fluids. Aphids can and will multiply quickly, especially in very hot and humid weather. If a plant is healthy and well-fed they should survive a brief encounter with these tiny pests. However, don't overfeed your plants, or you may increase aphids.
Two or three or three good hosings of water should usually get rid of a small aphid infestation. A large infestation that wont seem to go away needs a little more attention. A good solution is a supply of aphid predators such as ladybugs or parasitic wasps, which can be bought from mail-order nurseries or follow the links below.
For more severe infestations outdoors, spray with malathion. If using malathion on food crops you must wait before harvesting them. Check the label for the number of days of use. For indoor plants, wash the plant with insecticidal soap or spray them with resmethrin.
Remember, wrapping the base of a plant with aluminum foil will discourage aphids.
Plants with aphid damage can have several symptoms including decreased growth, yellowing, curled leaves, wilting, mottled leaves, browning, and unfortunate death. The removal of sap in the plants causes a loss of vigour, and the saliva from the aphid is extremely toxic to plants. Also, aphids tend to transmit disease-causing organisms such as plant viruses to plants.
The Life Cycle of a Green Apple Aphid
- A, adult female (sexually active)
- B, adult male
- C, young female
- D, female laying an egg
- E, eggs, turn from a color of green to black once laid
History of Aphids:
It is thought that aphids appeared over 280 millions years ago in the early Permian periods. It is thought that they fed upon plants like Cycadophyta and Cordaitales. A fossil, the oldest one known, is of the species Triassoaphis Cubitus from the triassic. The species number was small but greatly increased when angiosperms appeared 160 some million years ago. With angiospersms aphids were able to specialize. Cornicles did not show until the Cretaceous period.