The objective of this work was to analyze the genome of flax (Linum usitatissimum L.) using molecular marker techniques. For this purpose, AFLP-markers, RAPD- and ISSR-markers were chosen. Two recombinant inbred populations, derived from the crosses [Szegedi62 x Atalante] and [Viking x McGregor-E1747] were used for mapping. The resulted linkage maps were used then as a basis for mapping quantitative trait loci (QTLs) for the fatty acid pattern in the linseed oil via the composite interval mapping method. (1) The genetic diversity of the parental lines of the RI-population as well as of a sortiment of modern fibre-flax and oilseed cultivars was estimated on molecular level using RAPD-markers. The results demonstrate a relatively close relationship among the fibre-flax cultivars. In contrast, the oilseed cultivars were characterized by larger genetic distances. (2) For the RI-population I [Szegedi62 x Atalante], a molecular linkage map was calculated. This linkage map includes 139 marker loci located on 16 linkage groups with an average spacing of 6.9 cM. (3) Another linkage map was calculated for the RI-population II [Viking x McGregor-E1747]. Here, 118 AFLP marker loci were mapped, which are coupled in 17 linkage groups with an average spacing of 6.4 cM. (4) No clustering of markers was observed in any of the linkage maps. (5) A consensus linkage map containing 4 consensus linkage groups was designed. The average spacing of loci in these linkage groups was 4.1 cM. (6) The contents of the saturated fatty acids, palmetic acid (C16:0) and stearic acid (C18:0), as well as the contents of the unsaturated fatty acids, oleic acid (C18:1), linolic acid (C18:2) and linoleic acid (C18:3) in the seed oil, were estimated in both RI-populations by gas chromatography. (7) The contribution of these traits in the RI-populations and the correlations with each other were analyzed. In both populations a significant correlation between the relative content of stearic acid and the relative content of oleic acid was observed. The same was found for the relative contents of linolic and linoleic acid. (8) For all traits, several QTLs were estimated in both RI-populations. Some of these QTLs explain up to 60% of the total phenotypic variance in the respective fatty acid content. (9) A correlation between the QTLs for the traits relative content of linolic acid in the seed oil and relative content of linoleic acid in the seed oil was observed in population II [Viking x McGregor-E1747]. (10) Both, positive as well as negative, transgression effects were detected for each trait. Furthermore, several QTLs showed pleiotropic effects concerning different traits. The establishment of molecular marker techniques, and the development of molecular linkage maps is the first and unalterable step for the map based cloning of single genes. The localization and mapping of QTLs for the fatty acid pattern in the seed oil allows a direct application of the here presented linkage maps for marker assisted selection in linseed breeding. Furthermore, the availability of new oilseed cultivars, designed for the specific industrial demand, may allow an increased economy of flax cultivation.
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The objective of this work was to analyze the genome of flax (Linum usitatissimum L.) using molecular marker techniques. For this purpose, AFLP-markers, RAPD- and ISSR-markers were chosen. Two recombinant inbred populations, derived from the crosses [Szegedi62 x Atalante] and [Viking x McGregor-E1747] were used for mapping. The resulted linkage maps were used then as a basis for mapping quantitative trait loci (QTLs) for the fatty acid pattern in the linseed oil via the composite interval mappin...
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