Selection on pollen for linolenic acid content in rapeseed, Brassica napus L.

In order to enhance the economic value of edible rapeseed oil, an improvement of quality is necessary. Mutagenesis of rapeseed resulted in a low linolenic acid content and a low 'linolenic acid (C18:3) level to linoleic acid (C18:2) level' ratio, that is, the linoleic desaturation ratio (LDR), in the seeds of the Canadian variety 'Stellar'. As an early breeding marker for low linolenic acid content, the pollen fatty acid composition was determined on 80 doubled haploid plants derived from a single F-1 hybrid obtained from a cross between 'Stellar' and a high C18:3 variety 'Drakkar'. Fatty acid analysis on seed and pollen showed that the low C18:3 and the low LDR traits from the 'Stellar' variety were expressed in pollen and in seeds, and that a very close correlation (r = 0.88) existed between seed and pollen for these two trails. Thr inheritance of these traits is controlled by two major genes with additive effects; both in seed and pollen. However. minor genes also appeared to be expressed in pollen and seed. These genes may allow the production of plants with lower C18:3 levels than that of the low linolenic acid content parent. The efficiency of this new tool for early screening in breeding programmes is discussed.