关键词: 花色变化, 花色苷, 类黄酮, 鸳鸯茉莉, 大花茄, 茄科植物

Abstract: By way of measuring the flower color phenotype，the pH value，the content of soluble sugar and soluble protein，the enzymatic activity of PAL（phenylalanine ammonia‑lyase） and CHI（halcone isomerase），the content of anthocyanin，flavonoid and carotenoid in six flowering phases of Brunfelsia acuminata and Solanum wrightii，this study explored their color changing mechanism，to provide a theoretical basis for flower color breeding. Results showed that Brunfelsia acuminata and Solanum wrightii displayed similar change trend of increasing first and then decreasing in the content of soluble sugar and soluble protein，the enzymatic activity of CHI，the content of anthocyanin during flowering，
while displayed different change trends in the pH value，the enzymatic activity of PAL，the content of flavonoid and carotenoid. The contents of flavonoid（except initial flowering phase）and anthocyanin（except late full‑bloom phase and end of the flowing phase）of Brunfelsia acuminata were higher than those of Solanum wrightii，and all reached the peak value in the late flower bud phase. Six chromatographic components were detected in the anthocyanin extract of both plants. The a2 and a3 components of Solanum wrightii were identified as cyanidin chloride and petunia chloride，and the b4
component of Brunfelsia acuminate was identified as petunia chloride，and the rest components needed to be further determined. The correlation analysis showed that the chromaticity value indexes（L*，a*，b*，C*and h） were significantly correlated with the content of anthocyanin during flowering process in Brunfelsia acuminata，but not with the content of flavonoid. The chromaticity indexes L*，a*，b*，and C*were significantly correlated with the content of anthocyanin and flavonoid during flowering process in Solanum wrightii. The results indicated that the flower color of Brunfelsia acuminata was connected with the content of anthocyanin，and the flower color change was caused by the decline of anthocyanin content.Some anthocyanin which was synthesized and accumulated during the bud stage degraded under the intense sunlight，resulting in the color fading. However，the flower color of Solanum wrightii was controlled by the content of anthocyanin and flavonoid，the flower color change was not only related to the decline of anthocyanin content，but also to the proportion changes of anthocyanin components.

Key words: Flower color change, Anthocyanin, Flavonoid, Brunfelsia acuminata, Solanum wrightii, Solanaceae