Thomas R. Malthus (1798) has reasoned that the population increasing in geometric progression cannot be fed by agricultural systems since food production increases in arithmetic progression. Hence, the population will be limited to the carrying capacity of land by means of epidemic, war and famine.
The population of the world (as well as in Nepal) has been increasing day by day. The population of the world is projected to surpass 7.5 billion in 2015 A.D. Unfortunately, food production, as it depends on the vagaries of monsoon, low level of input and management, is lagging behind the population. The total production has not increased much and the volume of the world export shows a declining trend. What is more ominous is that the densely populated Africa and South-Asia are showing the symptoms of deteriorating agriculture and ecology. In Nepal also similar situation has seen. Food insecurity and scarcity has been increasing.
In the many parts of the world given the complexities in topography, climate and land holdings, adoption of modern technology is nearly impossible. The topography varies from plains to higher mountains, deserts to coastal areas. Climate and soil varies greatly over short distances and has resulted in numerous microclimatic packets having different capabilities. These all sorts of variations have been hindering the crop production and promoting food problems in the world.