Introduction to the Jinhua No. 4 Pear Variety and Its Main Characteristics

Jinhua No. 4 Pear is a superior strain of Jinhua Pear, native to Jinchuan County, Sichuan Province. Jinhua Pear is a natural seedling of Jinchuan Snow Pear. In 1959, the Sichuan Institute of Pomology and the Jinchuan County Agricultural Bureau discovered it during a survey. After years of evaluation of the mother tree and vegetative progeny, its superior traits were confirmed to be genetically stable, and it was named in 1975. In 1976, the Sichuan Agricultural College, in collaboration with Jinchuan County, carried out bud mutation selection of Jinhua Pear, successively selecting 14 single lines, among which 7624 performed most outstandingly in yield and quality traits, and it was named Jinhua No. 4.

1. Botanical Characteristics

The tree crown is round-headed. Young trees are strongly upright, spreading after fruiting, with thick and sturdy branches. The trunk is grayish-brown, rough-surfaced, with longitudinal fissures. One-year-old branches are yellowish-brown, with large and prominent lenticels, round or oblong, white. Two- to three-year-old branches are brown. Leaves are large, ovate, relatively thick, green, 15.2 cm long and 8.7 cm wide, with acuminate tips, broadly cuneate or rounded bases, sharply serrate margins that are relatively fine and dense, and most spine-like tips curving inward. Petioles are 7.1 cm long and 0.24 cm thick. Young leaves are dark red. Flowers are white, rarely reddish, with nearly round petals. Each inflorescence has 5 to 8 flowers, with a relatively large amount of pollen.

2. Fruit Characteristics

The fruit is very large or extra-large, with an average single-fruit weight of 378.5 g, and the largest reaching 1400 g. The fruit is elliptical or long ovate, with a longitudinal diameter of 10.4 cm and a transverse diameter of 8.4 cm. The skin is yellow, and the fruit surface is smooth with a waxy luster. Fruit dots are medium-large, moderately numerous, round or dot-shaped, yellowish-brown. The fruit stalk is 5.7 cm long and 3.1 mm thick. The stalk cavity is narrow and small, with a small amount of streak russeting around it. Sepals are deciduous; the calyx cavity is medium-wide and medium-deep, with furrows and ridges. The core is small, and the edible rate reaches 84.7%. The flesh is white, relatively fine in texture, crisp and tender, juicy, with few stone cells, and sweet in taste, containing soluble solids of 11.8% to 16.8%, soluble sugars of 10.43%, titratable acid of 0.150%, and vitamin C of 2.7 mg per 100 g, with superior quality. In Xingcheng, Liaoning, the fruit ripens in mid-October. It has strong storage tolerance and can generally be stored until April to May of the following year.

3. Biological Characteristics

(1) Growth habit: The plant has strong growth vigor. A 13-year-old tree is 4 to 6 m tall, with a trunk circumference of 36.8 cm and a crown diameter of 3.5 m x 3.6 m. New shoots average 75.4 cm in length and 0.66 cm in thickness, with internodes 3.8 cm long. Budbreak ability is strong, with a budbreak rate of 87.8%, while branching ability is relatively weak, generally producing 1 to 2 long shoots below the pruning cut.

(2) Fruiting habit: It has strong precocity, generally bearing fruit 2 to 3 years after planting, mainly on spur-type fruiting branches. The proportions of various fruiting branches are: short fruiting branches 53.98%, long fruiting branches 34.51%, and medium fruiting branches 11.51%. The continuous fruiting ability of fruit spurs reaches 39.2%, the fruit-setting rate of inflorescences is 91.6%, and each fruit spur sets 2 to 5 fruits on average. There is no preharvest fruit drop. It has strong high-yield potential; a 13-year-old tree can yield up to 3000 kg per 667 sq m, with relatively stable production.

(3) Phenological period: In Xingcheng, Liaoning, flower buds begin to swell in early April, first bloom occurs from late April to early May, full bloom in early May, and final bloom in mid-May, with a flowering period of 7 to 10 days. Spring shoots stop growing in early June, fruit ripens in mid-October, and leaves fall in mid-November. The fruit development period is 159 days, and the vegetative growth period is 221 days.

(4) Resistance: It has relatively strong adaptability and stress resistance, and can be cultivated in cool semi-dry, warm semi-dry, and warm humid regions. It is relatively cold-tolerant, moisture-tolerant, and drought-resistant. It has strong resistance to scab, leaf spot, rot, and ring rot, but is not resistant to aphids, rust, and pear psylla, so control measures need to be strengthened.

4. Agricultural Technical Characteristics

For large and medium-sized crowns, the modified leader or small-crown modified leader training system should be adopted. Planting density should be determined according to specific conditions; spacing of 2 to 4 m x 4 to 6 m may be used. Young trees should be pruned mainly by light pruning and long-shoot training, with appropriate thinning of crowded branches and competing branches. Summer pruning can open the branch angles through methods such as bending. Fruiting trees can be pruned by renewal pruning, thinning, and dormant shoot training. The crop load should be strictly controlled. Jinhua No. 4 Pear has strong continuous fruiting ability on fruit spurs and a high inflorescence fruit-setting rate, so flower and fruit thinning should be emphasized, leaving a single fruit per inflorescence and spacing fruits about 25 cm apart. Soil, fertilizer, and water management should be strengthened, especially by persisting in applying base fertilizer. According to weather and soil conditions, irrigation should be carried out before flowering, during the rapid shoot growth stage, during fruit enlargement, and before winter freezing. About 1 month before harvest, water should be strictly controlled, which helps increase fruit sugar content. Pollinizer cultivars can include Cangxi Snow Pear, Jinfeng Pear, Wujiuxiang, and others.

5. Suitable Promotion Areas and Development Prospects

Jinhua No. 4 Pear has large fruit and high quality, with high and stable yields. The fruit is storage-tolerant, and its stress resistance and adaptability are both relatively strong, making it suitable for extensive cultivation in white pear production areas.