• Kiviharju, E.
• Oksman-Caldentey, Kirsi-Marja
• Ritala, Anneli
• Suortti, Tapani
• Nuutila, Anna-Maria
• Hietaniemi, V.
• Pietilä, L.
• Manninen, O.
• Tanhuanpää, P.
• Kalendar, R.
• Schulman, A.

Abstract

Oat (Avena sativa L.) products lower the bloodcholesterol level, arisk factor in heart diseases.Moreover, Beta-glucan also helps to normalizethepostprandial blood glucose level and reduces the risk ofcolon cancer.These health benefits are mainly associatedwith high levels of mixed-linked(1,3)-(1,4)-Beta-D-glucan, a dietary fiber of which themain part issoluble. The amount of Beta-glucan isdependent on the genotype and thus canbe increased bycultivar breeding. In this study, modern biotechnologytoolswere applied in order to breed high Beta-glucan oatcultivars for food andprocessing purposes.To understand the inheritance of Beta-glucan content inoat and to enable DNA-marker-assisted selection in oatcultivar breeding, agenetic linkage map was constructedfor a Nordic oat cross. An Aslak xMatilda mappingpopulation of 137 totally homozygous DH-lines wasproducedby anther culture. The linkage map consisted ofover 600 PCR-basedDNA-markers, includingmicrosatellites, RAPDs, REMAPs, ISSRs, SRAPs andAFLPs.The QTL analysis showed two QTLs associated withBeta-glucan content.Together they explained about 37% ofthe variation in the DH lines. In bothchromosomalregions alleles from Aslak had a favorable effect onBeta-glucancontent. On the basis of the results, markerstightly linked to the genesthemselves may be developedfor DNA-marker assisted selection of highBeta-glucancontent containing oat breeding lines. QTLs were locatedalsofor other traits of interest. Another aim was tomodify the Beta-glucancontent of Finnish oat cultivarsthrough genetic engineering. Embryogeniccell cultureswere started from mature embryos of oat cultivars Aslak,Veli,and Kolbu. A microbial 1,3-Beta-glucan synthase wastransferred to oat celllines by particle bombardment andtransgenic plants were regenerated. Theexpression of themicrobial gene in transgenic cell cultures wasdemonstrated by semi-quantitative RT-PCR. The1,3-1,4-beta-glucan amountswere reduced and themolecular weight of the mixed-linked Beta-glucandifferedin some transgenic seed lines when compared tonon-transgeniccontrol seeds. The analyses of1,3-beta-glucan contents of transgenic celllines andseeds is ongoing. A basis exists for modifying oatBeta-glucancontents through genetic engineering.

Topics

• impedance spectroscopy