Comprehension : Comprehension

Q 253 / 466

UPSC CSE Prelims 2017

Many farmers use synthetic pesticides to kill infesting insects. The consumption of pesticides in some of the developed countries is touching 3000 grams/hectare. Unfortunately, there are reports that these compounds possess inherent toxicities that endanger the health of the farm operators, consumers and the environment. Synthetic pesticides are generally persistent in environment. Entering in food chain they destroy the microbial diversity and cause ecological imbalance. Their indiscriminate use has resulted in development of resistance among insects to insecticides, upsetting of balance in nature and resurgence of treated populations. Natural pest control using the botanical pesticides is safer to the user and the environment because they break down into harmless compounds within hours or days in the presence of sunlight Plants with pesticidal properties have been in nature for millions of years without any ill or adverse effects on the ecosystem. They are easily decomposed by many microbes common in most soils. They help in the maintenance of biological diversity of predators and the reduction of environmental contamination and human health hazards. Botanical pesticides formulated from plants are biodegradable and their use in crop protection is a practical sustainable alternative.
Which of the following statements is/are correct regarding bio pesticides?

  1. They are not hazardous to human health.
  2. They are persistent in environment.
  3. They are essential .to maintain the biodiversity of any ecosystem.

EXPLANATION

Correct Option (A)

Statement 1 is correct. The passage indicates that natural pest control using botanical pesticides is safer for the user and the environment. It explicitly states that these compounds break down into harmless substances within hours or days, and they contribute to the reduction of human health hazards.

Incorrect Options:

  • Statement 2 is incorrect. The passage clearly states that synthetic pesticides are generally persistent in the environment, whereas botanical pesticides are biodegradable and decompose easily and quickly. Therefore, botanical pesticides are not persistent.
  • Statement 3 is incorrect. While the passage mentions that botanical pesticides help in the maintenance of biological diversity of predators, it does not claim that they are essential for maintaining the biodiversity of any ecosystem. Their role is described as supportive rather than indispensable for overall ecosystem biodiversity.