Introduction to the new peach cultivar Ruiguang 22

1. Cultivar origin

Ruiguang 22 (90-6-11) was developed by the Institute of Forestry and Pomology, Beijing Academy of Agriculture and Forestry Sciences, in 1990 through sexual hybridization using Liguangte as the female parent and 82-48-12 (Qiuyu x NJN80) as the male parent. It was bred in 2000 and approved by the Beijing Municipal Crop Variety Approval Committee in 2001.

2. Cultivar characteristics

The cultivar has a vigorous tree habit with a semi-spreading tree shape. One-year-old branches are reddish brown on the sunny side and green on the shaded side. Leaves are lanceolate, with the leaf surface slightly concave inward, the leaf tip slightly rolled outward, and the leaf base acutely acute-cuneate; the leaf margin is purely serrate; the nectaries are kidney-shaped, mostly 2 in number. Flowers are rosette-shaped, petals ovate, pink; anthers orange-red, pollen abundant; the inner wall of the calyx tube is orange-yellow. The pistil is higher than the stamens. The fruit is short oval, with an average single fruit weight of 150 g and a maximum fruit weight of 196 g; the fruit apex is round and flat, the suture is shallow, and the stem cavity is moderately deep and wide; the ground color of the skin is yellow, and the fruit surface is nearly entirely covered with a red blush interspersed with fine dots, turning purplish red when fully ripe. The skin is moderately thick, not easy to peel, and the fruit is prone to cracking. The flesh is yellow, the same color as the flesh near the pit with no red; the flesh texture is firm-melting, fine, sweet in flavor, and aromatic. The pit is light brown, large, semi-clinging, and does not crack. The soluble solids content is 11%, Vc 8.09 mg/100 g flesh, soluble sugars 7.39%, organic acids 0.37%, and the sugar-to-acid ratio is about 20:1.

Ruiguang 22 is an early-maturing yellow, deeply red-blushed sweet nectarine. In the Beijing area, it generally buds in late March, reaches full bloom in mid-April, and ripens in early July, with a fruit development period of about 73 days. The average single fruit weight is 150 g, and the maximum fruit weight is 196 g. It is highly productive, with a 3-year-old tree averaging 500 kg per mu, and trees in full fruit stage averaging more than 2000 kg per mu.

3. Key cultivation techniques

(1) Based on the principle of both favoring early high yield and facilitating later management, the three-main-branch open-center training system can be planted at a spacing of 3 x 5 or 4 x 5 m, and the "Y" training system can be planted at a spacing of 2 x 5 m.

(2) Because it matures early, in addition to increasing the application of organic fertilizer in autumn, early fertilizer and water supply should be especially strengthened. Replenish tree nutrition in time before flowering and during the fruit enlargement stage. Before flowering, mainly apply nitrogen fertilizer; during the enlargement stage, use quick-acting nitrogen, phosphorus, and potassium fertilizers in combination to promote fruit enlargement and improve fruit quality.

(3) Young trees grow vigorously, so summer pruning should be strengthened to moderate tree vigor. After entering the fruiting stage, if vigorous vegetative growth occurs, the fruit inside the canopy and on the lower part of the tree will color poorly and have a bland flavor. Therefore, the extension angle of large branches should not be too wide, generally about 60 degrees is suitable, to prevent water sprouts from emerging on the upper side. At the same time, strictly control the development of the main branch leader and vigorous water sprouts inside the canopy, improve ventilation and light penetration, and promote fruit coloring and flower bud differentiation.

(4) Strengthen flower and fruit management. This cultivar has a high fruit-setting rate, so fruit should be thinned reasonably to help increase fruit size and improve quality. Yield should be controlled at 2000 kg/mu. Because insufficient light affects fruit coloring, leaf removal and branch thinning can be used to increase fruit coloring.

(5) In greenhouse cultivation, note that the temperature during the flowering period should not be too high or too low; the day-night temperature is best at 10-20 degrees, and the temperature during the fruit growth period is best between 20-30 degrees. Low temperature or insufficient light will prolong the fruit development period.