Breeding of a middle ripening, white-fleshed peach cultivar ‘Zhongtao 5’

Abstract:The traditional cross breeding is one of the most effective ways to breed new peach cultivars although many new technology occurred. Aiming at white-fleshed peach with round shape, big fruit and good quality, we choose‘Zhaohui’, bred by Horticulture Research Institute, Jiangsu Academy of Agri- cultural Sciences, as female parent and‘Sunfre’, a nectarine cultivar from USA for pollen donation. The pollen which was collected in March 1989 from the male parent‘Sunfre’was used for pollination in the balloom stage of the female parent‘Zhaohui’after artificial emasculation. 50 hybrid fruits were harvested after matured and the stone were cleared and stratificated under 2-7 °C in refrigeration house for about 90 days. When some of the seeds began to germinate, took out and sowed all the seeds in green- house. Finally, 32 hybrid seedlings were obtained. In early April of the next year, the seedlings were planted by 2.0 m × 4.0 m in breeding nursery according to the conventional cultivation management. Three years later, most of the trees began to flower and fruit‘. 89-4-32’, one of the hybrid seedlings, ex- hibited round, sweet and large fruit, accord with our breeding aim. The main economic and agronomic characters were stable, which were prior to the controls in the followed 4 fruited years. In 1996, it was upper-position grafted and evaluation was carried out for several fruiting years. The results showed that the main traits remained stable compared to the mother plant. In 2006, we choosed several orchard for production tests in Henan province. The comprehensive performance was stable and showed strong mar- ket competitiveness. In 2015, the selection was authorized to release and named‘Zhongtao 5’. The fruit of‘Zhongtao 5’is round and the top is flat or dimple, the suture is shallow and the two sides are symmetrical, mature degree is uniform. The fruit is large with average fruit mass of 263 g and the big- gest ones are more than 500 g. The fruit background is light-green or white, with medium fuzz. Mos surface of the fruit is covered with rose-red when ripening. The flesh is white, melting and juicy. The flavour is sweet with light aroma. The anthocyanin near the stone is medium. Soluble solid content is 12.6%-13.9%, total sugar content is 10.9%, total acid content is 0.27%, vitamin C content is 11.56 mg·100 g-1. The eating quality is excellent. The stone is cling, elliptical. The flower type is showy with 5 petals. It is fertile and yield high and stable. In Zhengzhou area, the leaf bud of‘Zhongtao 5’begin to break at the end of February to the beginning of March, and blooms in the late March, lasting 5-7 days. The fruits get into mature period in late July, and the fruit development period is about 120 days. The leaves begin to fall in early November. The growth period is 230 days approximately.