METHODS OF BREEDING FOR OIL QUALITY IN RAPE

Abstract

Reciprocal crosses were made between plants of Brassica napus with seed oil containing 40 and 0 per cent erucic acid. Gas liquid chromatographic analysis snowed an erucic acid content of 22 to 24 per cent in the crossed seeds. These results indicate that dominant gene action is absent and that fatty acid composition of the oil is controlled by the developing embryo. Thus the seed on an F₁ plant constitutes an F₂ population.Methods were developed to determine the fatty acid composition of oil from single seeds and from one cotyledon of an embryo. The analysis of a single cotyledon allows the genotype to be determined one generation earlier than if bulk samples are used, and the remainder of the seed may be grown into a normal plant. It is suggested that this half-seed technique may be used to determine the inheritance of other fatty acids in Brassica, and may also be applied to breeding other oil crops where the embryo, rather than the maternal sporophyte, controls the synthesis of fatty acids.