Changes

In the first half of the 20th century, Russian breeders improved the oil content, and choosed a cultivar-type with small stem and medium-sized head. Russian cultivars began spreading to western Europe. It is said that Hitler invaded the Soviet Union partly to have access to sunflower oil, because Germany eagerly needed cooking oil.

In the second half of the 20th century, Europe (and particularly France) began investing in research in "metropolitan" oil crops, as it could no longer rely on tropical oils. In 1969, at the Clermont-Ferrand INRA research station, the French Patrice Leclercq discovered a cytoplasmic male-sterility character by crossing a sunflower with ''Helianthus petiolaris'' Nuttall. This was the key event allowing an easy production of F1 hybrid seeds. This character is now used worldwide, and the world crop of sunflower has doubled. It has also come back to North America as a commercial crop, which it was not previously.