Labellum Colors of Oncidium Alliance and Their Flavonoid Composition
The labellum colors of Oncidium alliance were measured by a spectrophotometer,and the relationship between the color parameters and the flavonoid contents were discussed.The flavonoid composition in flowers were analyzed using a high performance liquid chromatography combined with mass spectrometry.The results showed that the labellum colors of Oncidium alliance were mainly distributed in purple and yellow region.The total anthocyanin and flavonoid contents were negatively correlated with lightness L*,and chromatic component b*.Furthermore,there were 5 anthocyanins(were cyanidin and peonidin glycosides) and 23 flavonoid glycosides(the aglycones were luteolin,quercetin,kaempferol,isorhamnetin,and chrysoeriol) were tentatively identified.These flavonoids were not detected in yellow and orange labellum,and they were contributed to the coloration of other Oncidium alliance except for yellow and orange parts.