rape

Farm and oilseed rape field, Alberta, Canada. The most westerly of the prairie provinces, Alberta's agricultural industry is a mainstay of its economy.

In botany, either of two plant species of the mustard family grown for their seeds, which yield a pungent edible oil. The common turnip is a variety of B. rapa and the swede turnip is a variety of of B. napus. (Genus Brassica rapa and B. napus, family Cruciferae.)

Oilseed rape, or canola, is the world's third most important oilseed crop. Plant breeders developed it from the ‘weed’ rapeseed (B. napus oleifera). The first variety was marketed 1974, and the bright yellow fields of oilseed rape in flower are now a familiar sight in the countryside.

Rape methyl ester provides a renewable replacement for diesel fuel that gives off fewer sooty particles and none of the sulphur dioxide that causes acid rain.

A German study 1995 estimated that yields of oilseed rape in northern Europe had been declining at a rate of 5% a year since 1990. This decline was linked to sulphur deficiency diseases resulting from reductions in sulphur emissions; although acid rain is harmful to plants it does provide necessary sulphur.