ABSTRACT
During the 20th century, particularly in the second half; agricultural products have increased remarkably to meet the requirements of the growing population of the world, which has reached the point of explosion. To meet the requirements sufficiently, some of the crops have gone into oblivion. The increase of a product is possible by two means. The first is to increase the area, which is under cultivation and the other is to increase the production in a unit-area (7). Although both these factors have been used in the last century to increase production, the share of yield increment has operated more than the share of increasing the area under cultivation. Take the example of India. In the year 1960 the production of wheat was about 400 kg per hectare but in the year 2000 each hectare of land produced 2400 kg (6). This means that the growth in yield has increased six fold during the last forty years. Not only in India, but also at the world level during the second half of the 20th century the area under cultivation of wheat has increased from 180 million hectares to 230 million hectares. This means that there has been an increase of 30% in areas under wheat cultivation, where as in the
same duration the operation of the growth of the wheat production has increased by 150% in every unit area, which has reached from 1000 to 2500 kgs per hectare. The production of wheat also in this duration has increased from 200 million tones to 600 million tones (6).
