FLAVONOLS ARE NOT ESSENTIAL FOR FERTILIZATION IN ARABIDOPSIS-THALIANA

Flavonols are plant metabolites suggested to serve a vital role in fer tilization of higher plants. Petunia and maize plants mutated in their flavonol biosynthesis are not able to set seed after self-pollination . We have investigated the role of these compounds in Arabidopsis thal iana. Like in all other plant species, high levels of flavonols could be detected in pollen of wild-type A. thaliana. No flavonols were dete cted in reproductive organs of the A. thaliana tt4 mutant in which the chs gene is mutated. Surprisingly, this mutant did set seed after sel f-fertilization and no pollen tube growth aberrations were observed in vivo. The role of flavonols during fertilization of Arabidopsis is di scussed.