napus

Brassica napus, commonly known as rapeseed or canola, is a flowering plant in the mustard family (Brassicaceae). It is an allotetraploid species (2n=38, genomes AACC) formed by hybridization between Brassica rapa (A genome) and Brassica oleracea (C genome). The name napus derives from Latin for turnip. The crop produces oil-rich seeds and is cultivated primarily for its seed oil and meal.

Napus is grown in temperate regions around the world, with major production in Canada, the European Union, China, and India. It is cultivated as winter or spring types; many winter varieties require vernalization to flower. Seeds are harvested for oil, while the meal remaining after oil extraction serves as a high-protein livestock feed. Oil content typically reaches about 40% of seed weight, though this varies with cultivar and growing conditions.

The oil produced is used for cooking and in food products, and canola describes cultivars bred for low erucic acid and low glucosinolate levels, optimized for human consumption. The press cake or meal after oil extraction is an important protein source for cattle, sheep, and swine, and can also be used for fertilizer or animal feed supplements. In some regions, rapeseed oil is processed into biodiesel.

Breeding and cultivation focus on increasing oil content and improving fatty acid composition, cold tolerance, and disease resistance. Hybrid varieties using male-sterility systems are common, and breeding includes conventional methods and, in regulated regions, gene editing or transgenic approaches. Common diseases include blackleg (Leptosphaeria maculans) and sclerotinia stem rot; pests such as flea beetles and aphids are managed through integrated pest management and crop rotation.