Breeding report of a new middle ripening apple cultivar‘Yueyan’

Abstract: ‘Yueyan’is a new middle ripening red apple cultivar selected from a cross‘Hanfu’and‘San⁃sa’in 2002. After artificial pollination, only 8 hybrid seeds were got in 2003. The seeds were sowed in2004, and 8 seedlings were got.‘S92’was considered as primary selection strains in 2008. It showed ear⁃lier bearing, good color, strong resistance, fruit economic characters outstanding. Regional adaptabilitytesting of the strains at more than ten sites including 10 comprehensive experimental stations of Liaoning,Shandong, Shanxi, Hebei, Sichuang, Yunnan and Xinjiang province from 2010. After seven years continu⁃ous observation on the original tree and regional adaptability testing,‘Yueyan’was examined and ap⁃proved by Liaoning Crop Cultivar Registration Committee in 2014. Trees of‘Yueyan’are vigorous with aspread growth habit. The trunk is smooth with dull grey-brown in color. Color of 1-year-old branch isbrown. The average length of branch is 33.4 cm. Matured leaves are green with slope upward and wraparound. The average length of leafstalk is 3.7 cm. The average length and width of leaf are 9.3 cm and 5.1cm, respectively. There are five flowers on each anthotaxy. Petals are pink white. The diameter of flower is 4.6 cm. The fruit is long-conical. The ground color is yellowish-green. The cover color of the fruits isfresh pink red without bagging. The average weight of fruit is 240 g, the biggest one is up to 309 g. Thefruit shape index is 0.89. The skin is smooth with bright-colored and beautiful. Flesh color is yellowishwhite.Flesh is thin and crisp, juicy, balanced sweet-tart, and aromatic. This variety has 8 to 10 seeds perfruit. Seeds color is yellowish-brown. The content of soluble solid is 13.4%, the content of total sugar is11.5%, the content of total acid is 0.42%, hardness is 8.2 kg·cm^-2. The quality is excellent. The fullbloom date of‘Yueyan’is in early May. The mature date of‘Yueyan’is in early September in XiongyueLiaoning area (east longitude 122°09′, north latitude 40°10′). The fruit development period is about 125 d. The germination rate is high, branching ability is strong. Most bearings came from both axillary flower budand spurs during young trees. The resistance to cold is strong. The resistance to cold in top buds of‘Yueyan’is stronger than that of‘Hanfu’. It is resistant to trunk canker. The fruit has 20 d or so storage-lifeunder room temperature, and also can be refrigerated to the following March. It is suitable for planting inDashiqiao, Yingkou city and southern area. It is early bearing, productive. This variety bear fruits afterplanted in the second years. The ability of yielding was average 30 000 kg·hm-2 in the fifth years. Spacingin the rows and spacing between rows are 2 m × 4 m with vigorous rootstock and 1.5 m × 4 m with dwarfrootstock. The suitable interstocks are‘Gm256’,‘SH’strains,‘Liaozhen 2’etc. The S genetypes wasS1S7. Suitable pollination varieties are chose from‘Fuji’‘Gala’‘Red Chief’‘Golden Delicious’‘Yueyanghong’and‘Hanfu’etc. Tree’s figure should be shaped as thin spindle mode, and the height is con⁃trolled in 3.5 to 4.0 m. Lateral branch sprouts easily in the young tree. It is necessary to open the shootsangle in time to relieve the growth and speed shaping so as to make it early fruit. Renewal the weakbranch groups after harvest to maintain the growth and improve the quality of fruits. High spindle mode isrecommend when use dwarf root-stocks, and keep the tree’s size as followed items: height is 3.0 to 3.5 m,the number of branches is 30 or so, angle of branch is from 110° to 120°, and the ratio of branch thick totrunk thick is from 1∶3 to 1∶5. Pole structure should be used to keep the tree hold to the soil, especially inyoung plant trees. Interstock trees should pay attention to help the branch of center leader. Limited reasonable load was within 45 000-75 000 kg·hm^-2. It should be timely harvest. The fruit of the tree fell on thecrisp if late harvest.