Breeding report of a new early-ripening and yellow- fleshed peach cultivar Jinchun

Abstract: Jinchun is a new early- ripening and yellow- fleshed peach cultivar derived from the cross seedlings between Jinxiu (peach) and Huyou 018 (nectarine) in 1999 at the Fruit Experimental Station, Shanghai Academy of Agricultural Sciences. It was initially selected as an excellent individual plant in 2004 for its good taste. After regional adaptability testing at an orchard in Zhuanghang town in Shanghai over eleven years from 2007 to 2018, it was finally selected in 2018 for its good quality. In 2018, a certificate issued by the Shanghai City Committee for Forest Variety Validation was obtained. The leaf of this cultivar is 17.62 cm long and 3.61 cm wide. It has rose-type flower with pink petal and fuchsia anther, which contains lots of fertile pollen. Blooming dates normally vary between late March and early April depending on different years, and the flowering period usually lasts 8-10 days in Shanghai. Fruit shape is ovate, and the fruit shape index is about 1.06-1.12. The average weight of fruit is around 161-176 g, with the maximum weight being 323 g. Background color of fruit is yellow and it is covered about 50% red blush on the skin surface. Its flesh is yellow, fine textured and juicy, the flesh of ripe fruit is easy to be separated from skin, and the firmness of mature fruit with skin is about 6-8 kg·cm-2 at harvest. Its stone is clingstone, and each stone contains only one seed. The average soluble solids content of mature fruit is about 10.2%-11.4%, the flesh tastes sweet and fragrant, and fruit quality is excellent. The fruit matures in mid-June in Shanghai area, and fruits are harvested from June 10 to 15 in recent years. The fruit development period is 78-82 d, and it ripens 8-10 d earlier than the cultivar of Jinxiang. Fruit storage capacity is medium, storage life at 0 ℃ is around 3 weeks and shelf life at room temperature is around 1 week. This cultivar can be planted alone without other pollinizer cultivar, and the spacing depends on planting density and cultivation objective. Good drainage and irrigation condi-tions in the orchard are necessary for plant growth and fruit production, and quantity of manures and chemical fertilizers could be applied base on the required yield. Although it can reach high yield by selfpollination, in order to improve fruit size and maintain suitable tree vigor, fruit thinning is necessary for this cultivar. It should be pruned at both dormant and growing seasons in Shanghai. Tree shape could be controlled by pruning, and three-limb open-center system, Y system and pillar system are suitable for this cultivar. Bud break rate and branching ability of this cultivar are normally medium, and it has good resistance to fruit disease and pest, waterlog, high temperature and high humidity. This cultivar can be grown in Shanghai, Jiangsu, Zhejiang, Anhui, Shandong and Fujian areas, where the yield is suggested to be controlled at 18.0-22.5 t·hm-2