resources Under specific conditions farmers can use most available methods to achieve optimum crop yields .Most of these methods aim at increasing the efficiency on the use of natural resources such as water, land area, nutrients, solar radiation and atmospheric CO2. The reduced availability of land and water because of urbanization and indus-trialization are related to the global population increase. The local changes in the availability of water due to climate change are hard to predict but farmers have demonstrated their ability to respond.The intensity of solar radiation is expected to remain constant,while an increase in atmospheric CO2 is predicted