Abstract
Rain agriculture of cereal crops is submitted on a high level of risk and uncertainty especially in the relative importance of agricultural areas which depend upon such a type of irrigation. Acreage productivity undo rain production conditions is full of risks due to the difference of rain full and its distribution. Therefore, the research tries to measure the type of the relation between Barely and Wheat crops production from one side and the level of rain fall through the stages of plant growth from another for the period 1980-2000 in Nineveh province. This quantity limit has its own importance directly upon food product and Iraqi food security. Depending upon the hypothesis which says that there is a strong relation between the ratios of rainfall and the productivity of both Wheat and Barely. There is also another strong relation between rain distribution upon the main stages of plant growth and the productivity of acreage for both crops .Econometric and analytical results have confirmed that there is a significant relation between rainfall and the productivity of both Wheat and Barely crops as a dependent variance. Also, there is a variation in relative importance for the relation between dependent variance and the distributional nature of rains during the stages of plant growth for the two crops of the study.
