The association of phytoecdysteroids with flowering in fat hen,Chenopodium album,and other members of the Chenopodiaceae

Very high concentrations of ecdysteroid are associated with flowering inChenopodium album. Highest concentrations are found in anthers, but significant levels are also found in the stamens, carpels and sepals. In contrast, pollen contains only low levels. The ecdysteroid profile is the same in anthers as in whole-plant extracts, with 20-hydroxyecdysone and polypodine B predominating. The results for flowers ofC. album are compared with the patterns determined for other chenopods (C. capitatum, C. polyspermum, C. anthelminticum, C. giganteum, C. quinoa andC. foliosum). The significance of these findings for plant-insect interactions and the relationship to the mode of plant pollination are discussed.