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Crop Protection

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My apple has a worm in it...gross! Pests are a natural part of the plant world; however, most consumers would be aghast if they found a pest in their produce. And farmers lose significant amounts of crops to pests each growing season. Your challenge is to select the most effective method of pest control for your crops. You also need to choose wisely so that your crop protection method has the smallest amount of negative impact on the surrounding natural environment. I don’t want to be a pest, but it’s time to start your investigation.

Planning and Carrying Out Investigations

Crop Protection Brochure

Crop Protection Brochure

What is crop protection?

Crop protection is the science of protecting crops from predators, disease, and weeds. Crop protection includes using chemical control, biological pest control, barrier approaches such as bird netting, animal psychology such as techniques to scare predators away, and biotechnology like genetic modification. The goal of crop protection is to produce the maximum amount of food at the highest quality possible. It has been estimated that without crop protection, 40% of the world's food would not exist.

What is a chemical control?

Chemical controls are methods of crop protection that use chemicals. This includes herbicides, insecticides, and fungicides. Herbicides are also known as weed killers. Many herbicides are specifically designed to kill unwanted weeds while not harming the crop that is being harvested. Insecticides are used to kill insects so the insects do not eat and harm the crop. Fungicides kill fungi which can kill crops or reduce the quality of the crops.

What is a biological control?

Biological control is the method of controlling pests by using their natural controls such as predators and diseases. For example, a biological control for insects may be birds that are predators of the insect. Farmers could plant native bushes that provide berries for the birds and introduce other food sources to encourage the birds to live in that area so that they will control the insects. Using natural predators to control pest populations is advantageous in that the predators are adapted to the environment that the pests live in, and they are very cost-effective.

What is an economic threshold?

The economic threshold of a pest is the population density of a pest at which it is economically necessary to invest in some kind of crop protection. If the population density of a pest is below the economic threshold, the farmer would spend more money trying to control the pest than would be saved by having healthy crops. If the population density of a pest is above the economic threshold, the farmer would lose more money due to losses in crops than would be saved by not controlling the pest.

What is pesticide drift?

Pesticide drift is the movement of part of a pesticide to a place other than where it was intended to go. For example, during application, part of a pesticide can get caught in the wind and blow onto crops that were not supposed to receive the pesticide. Runoff from farmland during rainstorms can carry pesticides into water sources. Pesticide drift can cause health problems for people and animals, and it can also cause environmental damage.

What are pollinators?

Pollinators are animals that spread pollen from one plant to another. When a plant receives pollen from another plant of the same species, it can produce seeds and fruits. Without pollinators, plants would not be able to produce seeds and would die out. Examples of pollinators include honey bees, butterflies, and even wasps.

How do insects build resistance to pesticides?

When a population of insects is treated with insecticide, not all of the insects die. Some of them can survive the insecticide because their genes make them resistant to the insecticide. When these insects reproduce, their offspring will have the genetic traits that make them resistant to the insecticide too. Because the insects that do not have these genes are killed and do not have a chance to reproduce, eventually the majority of the population is resistant to the insecticide.
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