Anatomical and biochemical studies of anthocyanidins in flowers of Anagallis monelli L. (Primulaceae) hybrids

Violet, lilac and red flower colors segregated in an F₃ population obtained from hybridizing blue and orange breeding lines of Anagallis monelli at UNH. One individual per color was studied, as well as “true-blue” cultivar ‘Skylover Blue’. Anatomical examination revealed typical petal layout with upper epidermis, loose mesophyll and lower epidermis. Cells in upper and lower epidermis were categorized by their vacuole color. Blue and red individuals had mostly blue and red cells, respectively. Lilac and violet individuals had blue and bicolored (red and blue) cells on both surfaces, and red cells on the lower epidermis only. Violet individuals had more blue cells on the upper epidermis than lilac individuals. Anthocyanidins were determined by HPLC for each petal epidermis. Blue flowers had only malvidin in both petal surfaces, red flowers had mostly delphinidin with traces of malvidin. Lilac and violet flowers had more malvidin than delphinidin. For violet and lilac flowers respectively, 2 and 3% delphinidin in upper petal surfaces result in a reddish tone while in the lower surface 33 and 25% delphinidin result in a red color. pH in upper and lower petal surfaces were significantly different for each individual, which may affect final flower color.