Breeding report of a new Vitis davidii cultivar Xiangci No. 2

Abstract: Xiangci No. 2, a new mid-maturing cultivar of Vitis davidii, was selected through seedling selection in Tongmu town, Zhongfang county, Huaihua City, China. Belonging to the East Asian species of V. davidii, Xiangci No. 2 exhibits bisexual flowers. Thorns are present on the canes and petioles, while young leaves are bright red-brown with sparse short hairs only along the veins on the abaxial surface, devoid of hairs between veins. The first inflorescence emerges at the 3rd to 5th node, predominantly at the 4th node, with 1 to 3 inflorescences per cane, mostly 2. Flowering occurs from late April to early May. Mature leaves are wedge-shaped with three lobes, exhibiting a green color, small size and medium thickness, with convex serrations on both sides of the margin. Winter vines are yellow-brown, with an oval cross-section and moderately dense, fine thorns. Grape clusters are predominantly cylindrical, moderately compact, and mostly without secondary clusters, averaging 136 g per cluster and 19.1 cm in length. Berries are round, with easily separable skin and flesh that adheres to the seeds, enclosing a fleshy sac. The berry shape index is 1.1, with an average berry weight of 2.2 g. Fruit powder is moderately thick, and the skin is thick. Berries start as green, and gradually fade to greenish-pink at maturity. Seeds are brown, lacking external transverse grooves, but displaying a distinct seed hilum. The soluble solids content is 18.5%, and the titratable acidity is 0.20%. In Hunan, Xiangci No. 2 initiates budbreak in early April, enters initial flowering in early May, the berry softens in early August, and matures in late August. The period from budbreak to maturity spans approximately 145 days, with berry setting to maturity taking roughly 105 days, classifying as a mid-season variety. It exhibits strong yield stability and pro-ductivity, with initial fruiting occurring in the second year after planting, yielding 2250-3000 kg·hm^-2 , and an average yield of 6000-9000 kg·hm^-2 in the third year. Fruiting canes emerge from the 2nd to 10th node of the fruiting mother canes. Xiangci No. 2 demonstrates good stress tolerance, strong drought resistance, and moderate tolerance to high temperatures and humidity. It is highly resistant to grape powdery mildew, anthracnose and gray mold but not resistant to downy mildew. It exhibits strong insect resistance but is not resistant to grape phylloxera. The variety is adaptable to various soil types. It is suitable for planting in spring and autumn in grape-producing regions of Hunan, Guizhou, Sichuan, Jiangxi, Fujian, Hubei, Yunnan, Guangdong provinces as well as Guangxi and Chongqing areas.