David Weiss

Publications (1)2.85 Total impact

• Source

  Available from: Stefan Martens

  Article: Modification of flower color and fragrance by antisense suppression of the flavanone 3-hydroxylase gene

  Amir Zuker, Tzvi Tzfira, Hagit Ben-Meir, Marianna Ovadis, Elena Shklarman, Hanan Itzhaki, Gert Forkmann, Stefan Martens, Inbal Neta-Sharir, David Weiss, Alexander Vainstain
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  ABSTRACT: Anthocyanins are the major pigments contributing to carnation flowercoloration. Most carnation varieties are sterile and hence molecular breedingis an attractive approach to creating novel colors in this commercially importantcrop. Characterization of anthocyanins in the flowers of the modern carnationcv. Eilat revealed that only the orange pelargonidin accumulates, due to a lackof both flavonoid 3prime,5prime-hydroxylase and flavonoid3prime-hydroxylase activities. To modify flower color in cv. Eilat, we usedantisense suppression to block the expression of a gene encoding flavanone3-hydroxylase, a key step in the anthocyanin pathway. The transgenic plantsexhibited flower color modifications ranging from attenuation to complete lossof their original orange/reddish color. In the latter, only traces ofpelargonidin were detected. Dramatic suppression of flavanone 3-hydroxylaselevel/activity in these transgenes was confirmed by northern blot, RT-PCR andenzymatic assays. The new phenotype has been stable for over 4 years ofvegetative propagation. Moreover, transgenic plants with severe colormodification were more fragrant than control plants. GC-MS headspace analysesrevealed that transgenic anti-f3h flowers emit higherlevels of methyl benzoate. The possible interrelation between pathways leadingto anthocyanin and fragrance production is discussed.
  Molecular Breeding 01/2002; 9(1-9):33-41. · 2.85 Impact Factor