Unit 15 Pests and Pesticides

1 Introduction

1.1 Read the text title and hypothesize what the text is about. Write down your hypothesis.

1.2 What do you know concerning this issue? List your ideas in the table left column “I know

I know that...	I have learnt that...

1.3 If you know answers to these questions write them down in the space given after each question.

1	What do you know about pests?
2	What did ancient people use to protect their crops?
3	Can you name the pesticide benefits?
4	Do pesticides effect on human body?
5	What actions can suppress both weeds and insect pests?
6	Can we avoid using toxic pesticides?
7	How can we protect ourselves from annoying pests?

4. Circle in the list the words and expressions you know. Write down their translation in the table and calculate the percentage of your lexical competence.

1	pest organisms		9	disturbed area
2	disease-causing		10	to food field
3	succession		11	livestock strain
4	protective clothing		12	accidental exposure
5	annoying creature		13	to protect smb.
6	sulfur ointments		14	behavioural changes
7	food supplies		15	to interfere with
8	pesticides		16	natural poisons

Foreign Language University Training

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odem chemical pesticides have saved millions of human lives by killing disease-causing insects and by increasing food supplies. Without modern chemical pesticides we would lose immense amounts of agricultural products, building supplies, historical artifacts, works of art, and other important materials. Our lives would be much less comfortable and convenient as well. But we must understand what these pesticides are doing and use them judiciously. We will study the major types of pests and pesticides and some of the benefits and problems involved in our battle against pests.

What Are Pests and Pesticides?

A pest is something of someone that annoys us, detracts from some resource that we value, or interferes with a pursuit that we enjoy. Of the millions of species of organisms only about one hundred plants, animals, fungi, and microbes cause 90 percent ’ of all crop damage worldwide! Insects tend to be the most frequent pests, in part because they make up at least three-quarters of all species on the earth. Most pest organisms tend to be generalists, opportunistic species that reproduce rapidly, migrate quickly into disturbed areas, and are pioneers in ecological succession. They compete aggressively against more specialized endemic species and can often take over a biotic community, especially where humans have disrupted natural conditions and created an opening into which they can slip.

Early Pest Controls

Using chemicals to control pests may well have been among our earliest forms of technology. People in every culture have known that salt, smoke, and insect- repelling plants can keep away bothersome organisms and preserve food. The Sumerians controlled insects and mites with sulfur 5,000 years ago. Chinese texts that are 2,500 years old describe mercury and arsenic compounds used to control body lice and other pests. Greeks and Romans used oil sprays, ash and sulfur ointments, lime, and other natural materials to protect themselves, their livestock, and their crops from a variety of pests.