Genetic transformation of the astaxanthin biosynthetic genes bkt and crtR-B into apple tree to increase photooxidation resistance

•Astaxanthin biosynthetic genes bkt and crtR-B were transformed into ‘Brookfield Gala’ apple.•Novel ketocarotenoids including astaxanthin and canthaxanthin were synthesized and accumulated in transgenic apple plants.•Transgenic plants with pink color have hither antioxidant activity and stronger photooxidation resistance compared to wide-type lines.