“It is a kharif crop which is grown in areas of 40- 50 cm annual rainfall. It is rarely irrigated and seldom grown in areas with annual rainfall of more than 100
cm. The ideal temperature for it is 25°C -30°C. Bright sunshine after light showers is very useful in the early stages of growth. It can be grown on poor light sandy soils and upland gravely soils. It is mainly grown in Rajasthan” In the above paragraph, which crop of the following is described?