Genetics and breeding of oilseed crops

Abstract

Breeding of oilseeds focuses on 3 prime objectives: 1) Selection and breeding needed for the introduction of an established oilseed crop to a new area; 2) oil quantity and quality; and 3) meal quantity and quality. One obvious way of increasing the quantity of both oil and meal is to increase yielding ability of cultivars. Oil content has been increased by reducing the thickness of the ovary wall, where the latter is part of the harvest, and/or the seed coat. Usually, increases in oil content achieved in this way are accompanied by an increase in protein content. Oil quality is measured primarily by fatty acid composition, the ideal fatty acid composition depending on the use of the oil. In rapeseed and mustard species the quality of the oil for edible use has been greatly improved by removing the erucic and eicosenoic acids. In sajflower 2 types of oil are available commercially, one with high levels (75–80%) of linoleic acid and another with high levels (75-80%) of oleic acid, the 2 types having different uses. An added component of oil quality is stability of fatty acid composition over a range of environments. Oilseed meals have been improved by increasing protein content, by changing the amino acid profile of the protein, and by reducing levels of toxic compounds.