Passage: Agriculture accounts for approximately 5% of Kazakhstan's GDP. Grain, potatoes, grapes, vegetables, melons and livestock are the most important agricultural commodities. Agricultural land occupies more than 846,000 square kilometres (327,000 sq mi). The available agricultural land consists of 205,000 square kilometres (79,000 sq mi) of arable land and 611,000 square kilometres (236,000 sq mi) of pasture and hay land. Over 80% of the country's total area is classified as agricultural land, including almost 70% occupied by pasture. Its arable land has the second highest availability per inhabitant (1.5 hectares).Chief livestock products are dairy products, leather, meat, and wool. The country's major crops include wheat, barley, cotton, and rice. Wheat exports, a major source of hard currency, rank among the leading commodities in Kazakhstan's export trade. In 2003 Kazakhstan harvested 17.6 million tons of grain in gross, 2.8% higher compared to 2002. Kazakhstani agriculture still has many environmental problems from mismanagement during its years in the Soviet Union. Some Kazakh wine is produced in the mountains to the east of Almaty.

Question: What are the major crops grown in Kazakhstan?
wheat, barley, cotton, and rice