Flower colour and flavonoid pigments composition of the petals in ornamental peach cultivars obtained by crossing with Prunus mira

Abstract

Ornamental peaches are flowering trees with petals ranging from white and pale pink to purple red colour. Prunus mira is often used in breeding programs as a donor of powdery mildew and leaf curl resistance. It also impacts on other traits including flower colour. The aim of our work was to study the composition of the flavonoid pigments in flowers of 5 parents and 4 new ornamental peach cultivars, originated from P. mira. The pigments were extracted with acid alcohol from fresh petals and were detected by HPLC analysis. P. mira is characterized by white petals with a pale purple nuance. Hybrids from crosses of P. mira and cultivars with purple red and purple pink flowers petals have lighter petal colour than the parental cultivars. Hybrids from crosses of P. mira and albiflorum cultivars have a light purple pink flower. Chromatographic analysis demonstrated 12 glycosides cyanides and peonidin in different combinations and also 8 glycosides kaempferol and quercetin in the petal samples. Among coloured trees, the highest amount of flavonols (114 mg g‑1) and the lowest amount of anthocyanins (0.46 mg g(‑1)) were found in P. mira flowers. In contrast, in P. persica 'Manifiс' purple red flowers only 16 mg g(‑1) of anthocyanins and 2.5 mg g(‑1) of flavonols were detected. Much more flavonols (55-88 mg g(-1)) and a little anthocyanins (1.2-3.4 mg g(-1)) are accumulated in purple pink flowers of hybrid cultivars 'Lel', 'Mirafic' and 'Zhisele'. This trend is saved in crosses with a white flower parent, and that is why 'Solveig' hybrid petals are light purple pink. The diversity of colour shades is probably due to different proportions of cyanides and peonidin glycosides. Thus, the use of P. mira in breeding programs provides opportunities for creating cultivars with new shades of flower colour and higher resistance against fungal diseases.