Overall grain production increased throughout the 1970s, peaking in the late 1970s and again in the early 1980s and decreasing somewhat by 1985. Wheat is a staple for most of the population. Bread is the most important single item in the Iranian diet, except in certain parts of the Caspian lowlands where rice is more commonly grown. Wheat and barley are planted on dry-farmed and irrigated lands and on mountain slopes and plains.
Wheat is used almost exclusively for human consumption, and barley is used mainly as animal feed.
Rice is the only crop grown exclusively under irrigation. The long- grain rice of Iran grows primarily in the wet Caspian lowlands in the northern provinces of Gilan and Mazandaran, where heavy rainfall facilitates paddy cultivation. Population growth and the rising standard of living stimulated production of the high-quality rice that could be used for export. Although the Ministry of Agriculture and Rural Development sought to develop rice as an export crop as early as 1977, by the end of that year 326,000 tons of rice had to be imported to meet domestic needs. In 1985 rice imports increased 3 percent over the previous year's 710,000 tons.