Breeding report of a new late-maturing sweet cherry cultivar Fujin

Fujin is a new late-maturing sweet cherry cultivar bred by the cross of Wanhongzhu × Rainier at the Yantai Academy of Agricultural Sciences. The breeding work started in 2003, and the seedlings were obtained through sowing in late March 2004. These seedlings were subsequently planted in the cherry hybrid nursery of Zhifu District, Yantai Academy of Agricultural Sciences in 2005. In 2007, the hybrid seedlings began to bear fruit, and the breeding code of 03-6-12 was identified as a superior line. In 2008, the superior line was grafted onto Daqingye rootstock, and it was planted in the sweet cherry selection nursery of Yantai Academy of Agricultural Sciences. The tree began to bear fruit in 2012, showing strong trees, large fruits, and entered the fruiting season from 2014 to 2016, with excellent comprehensive traits. In February 2017, it received approval from the Forest Variety Approval Committee of Shandong, and named Fujin, with a certificate number of Lu S- SV- PA- 018- 2016. The tree’s growth characteristics are as follows: it is moderately vigorous and semi-open in shape, with a height of 3.3 meters at 8th year and a trunk circumference of 64 centimeters. Its annual branches are light brown, with an average length of 50.5 centimeters and a pitch of 2.65 centimeters. The leaves are green, long elliptic, and have coarsely serrated margins. The nectar glands on leaf blade are small, kidney- shaped, and light red in color, mostly 2, opposite or oblique. The corolla is white, with a round petal shape, overlapping position, and a pistil stigma situated slightly lower than the stamen. The fruit of Fujin exhibits a kidney- shaped morphology, characterized by a concave top, with the average weight of 11.7 g, and a maximum weight of 15.9 g per fruit. The fruit stalk is of medium length, measuring 2.70 cm. The fruit’s base is yellow, while the surface is bright red. The flesh of the fruit is light yellow, and the juice is yellow-white. The flesh is hard and crispy, with a sweet flavor. The fruit is fresh and possesses excellenteating quality. The fruit’s soluble solids content (w) is 22.5%, and its edibility rate is 95.1%. Fujin exhibits high budbreak rate and branching capacity, resulting in an early substantial yield. The types of fruiting branches is notable, with the bouquet-like fruiting branches contributing to the most yield. The yield of 5-year-old trees is 867.6 kg·666.7 m-2 , and the yield of 8-year-old trees is 1 261.6 kg·666.7 m-2 . The fruit growth period is approximately 72 days, and it matures in the middle and late June in Yantai. The tree demonstrates resistance to low temperatures in winter and strong frost resistance during the flowering period. In the context of cultivation, the planting spacing is (2-2.5) m×4 m, and the pollination varieties include Hongdeng, Van and Santina. To mitigate the adverse effects of precipitation and low temperatures, it is advisable to construct appropriate facilities.