Summary

The cultivated species of sunflower is a native of America that was taken to Spain from Central America before the middle of the sixteenth century. It was being grown by Indians for food and for hair oil. Improved varieties had been developed in Europe before 1600.In recent years, the world's cultivated area had been steadily increasing. This is mainly the result of the breeding of dwarf high yielding hybrids that also facilitate mechanization. Another reason is the emphasis given to polyunsaturated acids for human consumption. Sunflower belongs to the genus Helianthus of the Compositae family. The inflorescences of the plants of this family are heads in which the fertile flowers are aggregated and bordered by rays, the corollas of sterile flower.The genus Helianthus includes 67 annual and perennial species. The cultivated sunflower is an annual plant with the scientific name of Helianthus annuus. It is an erect, unbranched, coarse annual, with a distinctive large, golden head, the seeds of which are often eaten and are commonly crushed for oil production.In Southern European countries a total of 2.66 million hectares of sunflower are grown each year. Annual sunflower seed production is equal to 3.92 million tons with an average seed yield of 1473 kg/ha. However, there are very large productivity differences among the various Southern European countries. These are related to the soil type, but mainly to climatic conditions in each country as well as to the availability of irrigation in the different areas. If we assume an average 50% oil content in the case of sunflower seeds, oil production ranges from as low as 280 kg/ha in Portugal to 1349 kg/ha in Italy, with an average overall yield of 738 kg/ha.

Full document