Question

Leaf curling is caused by:

• A. $S{O}_2$
• B. $O_3$
• C. $H_2$S
• D. CO

Answer 1

The correct option is D CO

Carbon monoxide is produced by incomplete oxidation of carbon. Complete oxidation of carbon monoxide will give carbon dioxide. The important sources of these gases are cigarette smoking, automobiles, burning of fuel in houses, industrial plants, power house etc. $C{O}_2$ is also released during respiration of animals and plants. High concentration of carbon monoxide causes leaf curling, reduced leaf size, leaf drop and reduced cellular respiration in the plants.