Q. Among the following, which one is the least water-efficient crop?

Explanation : 

Water Requirements of Various Crops

Sugarcane is considered to be the least water-efficient crop among the options provided: sugarcane, sunflower, pearl millet, and red gram. This is due to the fact that sugarcane is a high water-demanding crop. It requires a significant amount of water for its growth and development compared to the other crops listed.

Sugarcane

Sugarcane is a tropical and subtropical crop that thrives in regions with plenty of sunshine and water. It has a long growing season and needs a substantial amount of water throughout its growth cycle, which can last from 12 to 18 months. Sugarcane is often grown in irrigated settings, and it can consume between 1500 and 2500 millimeters of water during its growing period, depending on the climate and soil conditions.

Sunflower

Sunflower is a crop that is relatively more drought-tolerant than sugarcane. It has a deep root system that allows it to access water from deeper soil layers. While sunflowers do require a fair amount of water, especially during the flowering and seed filling stages, they are generally more water-efficient than sugarcane.

Pearl Millet

Pearl millet is known for its drought tolerance and ability to grow in arid and semi-arid regions with low rainfall. It has a short growing season and can produce grain with much less water than sugarcane. This makes pearl millet a highly water-efficient crop.

Red Gram

Red gram (also known as pigeon pea) is another drought-resistant legume that can be grown in regions with less water availability. It has a deep root system that helps it extract moisture from deep soil layers. Red gram can be cultivated with limited water resources and still produce reasonable yields.