Biological Control of Pests IELTS Reading Answers

Biological Control of Pests Reading Answers is a useful IELTS Academic Reading practice passage for students who want to improve their reading speed, keyword identification, and answer accuracy. This passage explains how excessive pesticide use affects crops, human health, and the environment, and how biological control can be used as a safer alternative.

In this practice test, you will find IELTS Reading questions based on three common question types: Matching Headings, Sentence Completion, and Multiple Choice Questions. Read the passage carefully, attempt the questions first, and then check the answer key with explanations.

About the Biological Control of Pests Reading Passage

The Biological Control of Pests IELTS Reading passage discusses the harmful effects of synthetic pesticides and introduces biological control as an eco-friendly method of pest management. The passage also talks about pesticide resistance, treadmill syndrome, the role of CIBC, and real examples of biological control used in countries like India, Sri Lanka, and the United States.

This passage is helpful for IELTS aspirants because it improves your ability to locate information, understand scientific vocabulary, and answer different IELTS Reading question formats accurately.

IELTS Reading Passage: Biological Control of Pests

Read the passage below and answer Questions 1–13.

Biological Control of Pests

The excessive use of synthetic chemicals to control pests has become a serious concern for agriculture, the environment, and human health. Although pesticides were originally introduced to protect crops and increase production, their long-term impact has created several problems. The heavy use of pesticides has disturbed the ecological balance and has also resulted in the development of chemical-resistant pests.

According to research by the Food and Agriculture Organisation, more than 300 species of agricultural pests have developed resistance to different chemicals. In addition, over 100 disease-spreading pest species have become highly resistant to commonly used insecticides. This shows that chemical pesticides may provide temporary control, but they do not offer a permanent solution.

One major disadvantage of pesticides is that they kill harmful insects as well as many useful organisms that support crop growth. This creates an imbalance in nature. Agricultural scientists and environmental experts often describe this situation as treadmill syndrome. It means that farmers keep using stronger chemicals, but pests continue to adapt and become more resistant.

The effects of treadmill syndrome were clearly seen in Central America, especially among cotton farmers. During the 1940s, chemical-based intensive agriculture became popular, and farmers started using pesticides frequently to increase crop production. In the 1940s, insecticides were sprayed around eight times in a season. By the mid-1950s, this number had increased to 28 times in one season, which led to the rise of three new chemical-resistant pest varieties.

By the mid-1960s, four more pest varieties had appeared. Farmers were forced to increase pesticide use even further. In some cases, almost 50% of the cost of cotton production was spent on pesticides. Eventually, spraying reached up to 70 times in one season, resulting in another group of genetically stronger insect species.

Today, many pesticide products available in the market are not tested properly. Some of their chemical properties may cause serious health issues such as cancer, genetic mutations, and other harmful effects. Environmental agencies in the United States have warned about the dangers of such chemicals. DDT is one of the most well-known harmful chemicals identified by the United States National Resource Defence Council.

Because of the risks linked with chemical pesticides, biological control has gained attention as a safer and more sustainable method. Biological control uses natural enemies of pests, such as predators, parasites, or pathogens, to control pest populations. Compared to chemical pesticides, this method is cost-effective, long-lasting, less harmful, non-polluting, and self-dispersing.

The Commonwealth Institute of Biological Control, also known as CIBC, is located in Bangalore and has a network of scientific laboratories and local stations across the world. It is an important non-commercial research organisation that works on biological pest control by developing natural predators and parasites. CIBC also acts as an international centre for the exchange of biological agents used in pest control.

CIBC used a seed-feeding weevil from Mexico to control the harmful parthenium weed, which affects agriculture and human health in Australia and India. Similarly, the Regional Research Laboratory in Hyderabad, supported by CIBC, has been experimenting with an Argentinian weevil to control water hyacinth. According to Mrs Kaiser Jamil from RRL, the Argentinian weevil does not harm food plants, while a pair of adult insects can destroy the weed within four to five days.

There are several successful examples of biological control around the world. In Sri Lanka, coconut groves were once affected by leaf-mining hispides, but a larval parasite from Singapore helped stop the pest from spreading. In another case, Neodumetia sangawani, a natural predator from India, successfully controlled the Rhodes grass-scale insect in parts of the United States. In Kerala, scientists from Kerala Agricultural University used a beetle native to Brazil, Neochetina bruchi, to clear a 12-kilometre-long canal from the weed Salvinia molesta, commonly known as “African Payal” in Kerala.

Biological Control of Pests Reading Questions

Questions 1–5: Matching Headings

The reading passage has nine paragraphs. Choose the correct heading for each paragraph from the list of headings below.

Write the correct letter as your answer.

List of Headings

A. Pesticides today
B. Treadmill syndrome and its consequences
C. Introduction to CIBC
D. Examples of biological control around the world
E. India’s contribution to biological pest control

1. Paragraph about RRL and Argentinian weevil
2. Paragraph about harmful pesticide products available today
3. Paragraph about Central American cotton farmers
4. Paragraph about global examples of biological control
5. Paragraph about CIBC and its role

Questions 6–10: Sentence Completion

Complete the sentences below.

Write NO MORE THAN TWO WORDS from the passage for each answer.

6. Spraying reached 70 times in one season and created another group of __________ insect species.
7. __________ was successful in controlling the Rhodes grass-scale insect.
8. Scientists and ecological experts call this situation __________.
9. The Regional Research Laboratory is experimenting with an __________ to control water hyacinth.
10. Biological control is considered good because it is non-polluting and __________.

Questions 11–13: Multiple Choice Questions

Choose the correct letter A, B, C, or D.

11. In Kerala, Salvinia molesta is also known as:

A. African Payal
B. Asian Payal
C. American Payal
D. Indian Payal

12. The beetle native to Brazil was called:

A. Salvinia molesta
B. Neodumetia sangawani
C. Neochetina bruchi
D. None of the above

13. During which period was chemical-oriented intensive agriculture at its best?

A. The 1940s
B. The 1950s
C. The 1960s
D. All of the above

Biological Control of Pests Reading Answers Key

Biological Control of Pests Reading Answers with Explanation

1. E – India’s contribution to biological pest control

The paragraph mentions CIBC’s work with a seed-feeding weevil from Mexico and RRL Hyderabad’s experiment with the Argentinian weevil. This shows India’s role in biological pest control research.

2. A – Pesticides today

The paragraph explains that many pesticide products available today are not properly tested and may cause cancer, mutations, and other health problems.

3. B – Treadmill syndrome and its consequences

The paragraph discusses Central American cotton farmers and how repeated pesticide use led to resistant pests. This is a direct example of treadmill syndrome.

4. D – Examples of biological control around the world

The paragraph gives examples from Sri Lanka, India, the United States, and Kerala. Therefore, the best heading is examples of biological control around the world.

5. C – Introduction to CIBC

The paragraph introduces the Commonwealth Institute of Biological Control, its location, network, and role in biological pest control.

6. Genetically stronger

The passage states that spraying reached 70 times in one season and created another group of genetically stronger insect species.

7. Neodumetia sangawani

The passage says that Neodumetia sangawani, a natural predator from India, controlled the Rhodes grass-scale insect.

8. Treadmill syndrome

The situation where pests become resistant and farmers keep using more chemicals is called treadmill syndrome.

9. Argentinian weevil

The Regional Research Laboratory in Hyderabad was experimenting with an Argentinian weevil to control water hyacinth.

10. Self-dispersing

The passage describes biological control as non-polluting and self-dispersing.

11. A – African Payal

In Kerala, Salvinia molesta is commonly known as African Payal.

12. C – Neochetina bruchi

The beetle native to Brazil is called Neochetina bruchi.

13. A – The 1940s

The passage clearly mentions that chemical-oriented intensive agriculture was at its best during the 1940s.

IELTS Reading Tips for Biological Control of Pests Passage

To solve this passage effectively, first read the questions and underline keywords such as pesticides, CIBC, treadmill syndrome, Argentinian weevil, African Payal, and Neochetina bruchi. These keywords help you locate the correct part of the passage quickly.

For Matching Headings, do not focus only on one word. Read the complete idea of the paragraph and then choose the heading. For Sentence Completion, copy the exact words from the passage and follow the word limit carefully. For Multiple Choice Questions, eliminate the wrong options first and then select the best answer.

Conclusion

The Biological Control of Pests Reading Answers practice test is useful for improving IELTS Reading skills, especially for Matching Headings, Sentence Completion, and Multiple Choice Questions. This passage also helps students understand scientific vocabulary related to agriculture, environment, and pest control.

For better IELTS Reading performance, always practise with a timer, identify keywords, and check your answers with explanations. Regular practice will help you improve accuracy, speed, and confidence in the IELTS Reading test.

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