Comprehension : Comprehension

Q 392 / 466

UPSC CSE Prelims 2012

Chemical pesticides lose their role in sustainable agriculture if the pests evolve resistance. The evolution of pesticide resistance is simply natural selection in action. It is almost certain to occur when vast numbers of a genetically variable population are killed. One or a few individuals may be unusually resistant (perhaps because they possess an enzyme that can detoxify the pesticide). If the pesticide is applied repeatedly, each successive generation of the pest will contain a larger proportion of resistant individuals Pests typically have a high intrinsic rate of reproduction, and so few individuals in one generation may give rise to hundreds or thousands in the next, and resistance spreads very rapidly in a population.

This problem was often ignored in the past, even though the first case of DDT (dichloro diphenyltrichloroethane) resistance was reported early as 1946. There is exponential increase in the numbers of m vertebrates that have evolved resistance and in the number of pesticides against which resistance has evolved. Resistance has been recorded in every family of arthropod pests (including dipterans such as mosquitoes and house flies, as well as beetles, moths, wasps, fleas, Lice and mites) as well as well as in weeds and plant pathogens, Take the Alabama leaf-worm, a moth pest of cotton, as an example. It has developed resistance in one or more regions of the world to Aldrin, DDT, dieldrin, endrin, lindane and toxaphene.

If chemical pesticides brought nothing but, problem-if their use was intrinsically and acutely unsustainable — then they would already have fallen out of widespread use. This has not happened. Instead, their rate of production has increased rapidly. The ratio of cost of benefit for the individual agricultural producer has remained in favour of pesticide use. In the USA insecticides have been estimated to benefit the agricultural products to the tune of around $5 for every $1 spent.

Moreover, in many poorer countries, the prospect of imminent mass starvation, or of an epidemic disease, are so frightening that the social and health cost of using pesticides have to be ignored. In general, the use of pesticides is justified by objective measures such as lives saved, ‘economic efficiency of food production’’ and total food produced. In these very fundamental senses, their use may be described as sustainable. In practice, sustainability depends on continually developing new pesticides that keep at least one step ahead of the pests pesticides that are less persistent, biodegradable and more accurately targeted all the pests.

Why is the use of chemical pesticides generally justified by giving the examples of poor and developing countries?

  1. Developed countries can afford to do away with use of pesticides by adapting to organic farming, but it is imperative for poor and developing countries to use chemical pesticides.
  2. In poor and developing countries, pesticides address the problem of epidemic diseases of crops and eases the food problem.
  3. The social and health costs of pesticides use are generally ignored in poor and developing countries.

Which of the statements given above is/are correct?

EXPLANATION

Correct Option (c)

Statement 2 is correct. The passage explicitly states that in many poorer countries, the prospect of "imminent mass starvation, or of an epidemic disease" is so severe that the use of pesticides is justified. This directly indicates that pesticides address the problem of epidemic diseases affecting crops and contribute to easing food scarcity, thereby saving lives and ensuring food production.

Incorrect Options:

Statement 1 is incorrect. The passage does not provide any information regarding developed countries' ability to transition to organic farming or their imperative to use chemical pesticides. This assertion is an external assumption not supported by the provided text.

Statement 3 is incorrect. The passage mentions that in "many poorer countries," the social and health costs of pesticide use "have to be ignored" due to the overwhelming threat of starvation or disease. While this describes a consequence or a condition under which pesticides are used, the primary justification, as presented in the text, is the prevention of mass starvation and epidemic diseases (as captured in Statement 2), rather than the act of ignoring costs itself being the justification. The ignoring of costs is a result of prioritizing food security and disease control.