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A gene for flower colour fading in Petunia hybrida
P de Vlaming1, J E van Eekeres, H Wiering
1Department of Genetics and Plantphysiology, Universiteit van Amsterdam, Amsterdam, the Netherlands.
Abstract:
Full coloured Petunia hybrida flowers lose their colour and become completely white if the gene Fa is dominant. This gene is only expressed in mutants with the pH gene Ph4 homozygous recessive. It is shown by genetical experiments that the fading is restricted to the 3-rutinosido(p-coumaroyl)-5glucoside glycosylation pattern of anthocyanins. The 3-glucosides and 3-rutinosides show a weak fading only.
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