What are the characteristics of the new peach cultivar Ziqi?

'Ziqi' (see color photo on inside back cover) is a new ornamental peach cultivar selected from seedlings by the authors in 2000 after subjecting open-pollinated seeds of 'Ziyetao' (purple-leaf peach) to 1 radiation treatment. After 6 years of regional trials, the cultivar's overall ornamental traits are excellent and stable. Compared with its female parent 'Ziyetao', its flowering period is 8-12 d earlier, making it an early-flowering cultivar; its flower color is bright and vivid, its flower diameter is larger, its flowering is dense, and its leaf color is purplish red. In 2006, it passed the on-site acceptance organized by the State Forestry Administration and obtained plant variety rights. Cultivar characteristics

The tree is vigorous, with a semi-spreading habit, and strong bud-break and branching ability. The trunk bark is grayish brown, with numerous lenticels. A 6-year-old tree is 4.5 m tall, with a trunk circumference of 44.6 cm. One-year-old branches are hairless, glossy, and purplish red on the sunny side. Leaves are long elliptic-lanceolate, (9.1±0.59) cm long and (3.2±0.45) cm wide, smaller than those of the female parent. The leaf surface is flat, the leaf tip is acuminate, the leaf base is cuneate, and the leaf margin is serrate. The leaf color is dark purplish red in spring and slightly fades in summer. The petiole is thick and sturdy, about 1 cm long, usually with 2-4 reniform glands. The flower is plum-blossom-shaped and bright pink, with a pedicel 0.3-0.5 cm long and a flower diameter of 3.9-4.4 cm, double, with purplish brown sepals, 1 whorl, 5 in number, externally covered with white hairs, long ovate. Petals number 12-18, spoon-shaped. Stamens number 29-36, with both filaments and anthers red, and the basal stamens slightly petaloid. There is 1 ovary, which can develop into fruit. The fruit is round-spherical, with a rounded tip, longitudinal diameter (3.09±0.55) cm, transverse diameter (3.06±0.43) cm, densely pubescent, with a shallow suture, symmetrical on both sides, green skin, and a red blush on the sunny side. The flesh is white, crisp, with little juice, a small amount of fiber, free-stone, aromatic, and sweet-sour. It flowers early and has a long flowering period. In Tai'an, Shandong, the first flowers open in late March, earlier than the female parent, and the flowering period is 18-21 d. Flower density is high; on 1-year-old long branches, the flower density is (6.38±1.58) flowers/din, greater than that of the female parent. The flower color is lighter than that of the female parent (Royal Horticultural Society Color Chart 62B; its female parent is 59D), creating a strong contrast with the leaves and giving a good ornamental effect. Key cultivation techniques

According to the distribution of its female parent and combined with the ecological regionalization of the United States Department of Agriculture (USDA), 'Ziqi' can be cultivated in zones 5-9 in our country. Because the tree vigor is somewhat excessive and the tree habit is upright, attention should be paid to summer pruning, moderately opening the branch angles to control excessive vigor, moderating tree vigor, and promoting flower bud formation. This cultivar has no particular sensitivity to adverse environmental injury or pests and diseases.