Haploids in the Improvement of Linaceae and Asteraceae

Abstract

The family Linaceae includes herbs and shrubs. Its genus Linum comprises almost 200 species, which are spread over the temperate and warm temperate region of the northern hemisphere, mostly in Europe and Asia, but also in America. Linseed (syn. flax, Linum usitatissimum) is the only important crop species of the Linaceae. It is one of the oldest cultivated plants, having been grown for about 8,000 years. The crop is adapted to warm and cool temperate climates. It can be used as an oilseed and as a fibre crop. In addition, the seed is traditionally used in therapeutics because of its laxative properties. The oilseed types (linseed or oil flax) compared to fibre types (flax) have shorter and thicker stems with more branches, whereas flax produces fewer capsules and smaller seeds than linseed. The taller flax type is usually cultivated in cool, temperate regions and used for textiles (Luhs and Friedt 1994). The annual global production of flax fibre and tow is about 647,000Mt, with China, Spain, France and the Russian Federation as the major producers (FAO 2003). The production of fibre in the EU-15 countries dropped between 25 and 52% from 2000 to 2001 (EC 2002). The shorter linseed types are mainly grown in the warmer climates. Shorter fibres from the oilseed types are used in the manufacture of fine papers and for industrial fibre products such as the interior panelling of some cars (Berglund 2002). The seed is processed into a variety of diverse products from breads to linseed oil for environmentally friendly paints and concrete preservation to linoleum flooring. Linseed contains oil with a high alpha-linolenic acid (50%) essential for humans but with short shelf life due to autoxidation, a high percentage of dietary fibre, both soluble and insoluble, and the highest content of lignans of all grain crops. It is considered as a healthy food additive. The rapid drying property of the oil to form a natural