Contribution made by the carotenoid cleavage dioxygenase 4 gene to yellow colour fade in azalea petals
- 434 Downloads
Carotenoid content, composition, and the expression patterns of carotenoid biosynthesis and cleavage genes during petal development were compared among a yellow-flowered deciduous azalea (Rhododendron japonicum f. flavum), a white-flowered evergreen azalea (‘Miyamasatsuki’), and their progeny, to determine the factors that cause reduction in carotenoid content as the petals of the progeny develop. During the early, green petal flowering stage, total carotenoid contents were 31.27 μg g−1 Fresh Weight (F. W.) in R. japonicum f. flavum, 17.84 μg g−1 F. W. in ‘Miyamasatsuki’, and 42.18 μg g−1 F. W. in their progeny. During subsequent flower development, total carotenoid contents remained similar to the green petal stage for R. japonicum f. flavum. However, the content decreased in ‘Miyamasatsuki’ and their progeny at one day before anthesis, and became less than 3 μg g−1 F. W. during the later stages. The expression levels of PSY and PDS increased significantly in R. japonicum f. flavum than in ‘Miyamasatsuki’ as the flowers developed. Their expressions in the progeny were mid-way between both parents. The expression level of CCD4 was significantly higher in ‘Miyamasatsuki’ and the progeny than in R. japonicum f. flavum for all development stages. This result suggested that the high expression level of CCD4, which was inherited from ‘Miyamasatsuki’, was the main factor controlling the reduction in carotenoid content in the progeny.
KeywordsCarotenoid content CCD4 Fading of petal colour Rhododendron
This work was supported by a Grant-in-Aid for Scientific Research (C) (No. 24580047) from the Japan Society for the Promotion of Science (JSPS).
- Davies BH (1976) The Carotenoids. In: Goodwin TW (ed) The chemistry and biochemistry of plant pigments, vol 2. Academic Press, London, pp 38–165Google Scholar
- Galle FC (1985) Deciduous azaleas. In: Galle FC (ed) azalea. Timber Press, Portland, pp 63–116Google Scholar
- Goodwin TW, Britton G (1988) Distribution and analysis of carotenoids. In: Goodwin TW (ed) Plant pigments. Academic Press, London, pp 62–132Google Scholar
- Noguchi Y (1932) Studies on the species crosses of Japanese Rhododendron. I. On the crossability between various species and the cotyledon colour of F1 seedlings. Japan J Bot 6:103–124Google Scholar
- Santamour FS Jr, Dumuth P (1978) Carotenoid flower pigments in Rhododendron. HortScience 13:461–462Google Scholar
- Spathmann W (1980) Flavonoids and carotenoids of Rhododendron flowers and their significance for the classification of Rhododendron. In: Luteyn JL, O’Brien ME (eds) Contributions toward a classification of rhododendron s. The New York Botanical Garden, New York, pp 247–275Google Scholar
- Yamaguchi S (1986) In-vitro culture of remote hybrid seedlings aiming to breed new yellow flowered evergreen azalea. Plant Cell Incompat Newsl 18:50–51Google Scholar
- Yamazaki T (1996) A revision of the genus Rhododendron in Japan, Taiwan, Korea and Sakhalin. Kokusai Bunken Insatsusha, TokyoGoogle Scholar