Analysis of the Results of Introduction and Observation Trials of Hongxiangsu Pear

Hongxiangsu pear is a red pear cultivar bred by the Zhengzhou Fruit Research Institute of the Chinese Academy of Agricultural Sciences through hybridization with Korla fragrant pear (Pyrus sinkiangensis) as the female parent and E pear as the male parent. It was introduced to Luan County, Hebei in 2001. Through 6 years of observation, its appearance, quality and economic benefits are all better than local pear cultivars. This cultivar has a brilliant appearance, bears fruit early, is high-yielding, and has strong adaptability; it is relatively resistant to pear scab and pear black spot. It is a very promising new red-skinned, late-maturing, storage-tolerant pear cultivar. The performance of this cultivar locally is described below.

(1) Fruit traits The fruit is long ovoid, with an average single fruit weight of 200.0 g and a maximum fruit weight of 498.0 g. The ground color of the skin is green-yellow, with 2/3 of the sun-exposed side bright red; the fruit surface is clean and smooth, with large lenticels. The flesh is white, tender and fine in texture, with few stone cells, abundant juice, sweet taste and strong aroma; the quality is excellent. It can be stored for 2-3 months at room temperature.

(2) Growth and fruiting habits The growth vigor is moderate, the budbreak rate is high, the branching ability is medium, and the branches within the canopy are slightly sparse. Long branches are prone to forming flower buds after being laid flat, with a high flower formation rate, and it has the habit of fruiting on axillary flower buds. It is early-bearing and high-yielding: flowers can be seen in the 2nd year after planting, and it bears fruit normally in the 3rd year, with an average yield of 8 kg per tree; in the 4th year the average yield is 25 kg per tree, with an average yield of 2000 kg per 667 sq m; in the 5th year it enters full bearing, with a yield of 3000 kg per 667 sq m.

(3) Harvest period Hongxiangsu pear ripens in late September. Only when harvested at the ripe stage can it maintain the cultivar's inherent color, aroma and taste; harvesting early will seriously affect the area and depth of coloration, and will also affect flavor and quality.

(4) Key points of cultivation techniques To increase the number of branches, young trees should have the leaf buds in the middle and lower parts of 1-2-year-old branches notched before early spring budbreak to promote their sprouting and growth into medium and long branches. Notching is carried out 1 mm above the leaf bud, reaching deep into the xylem. Growth regulators such as branch-promoting agents and germination promoters can also be applied to the leaf buds to promote their sprouting and growth. Hongxiangsu pear has a high fruit-setting rate, so flower and fruit thinning should be carried out. If fruit set is left unchecked, it can easily lead to excessive fruit set, small fruit and low commercial value. Flower thinning is carried out from the flower bud separation stage to the petal-fall stage, leaving 1 inflorescence every 15-20 cm, with 2-3 flowers per inflorescence; fruit thinning is carried out 15-25 days after full bloom, first removing deformed fruit and fruit damaged by pests and diseases, leaving 1 fruit per inflorescence. Through flower and fruit thinning and a reasonable crop load, together with strengthened management, the single fruit weight of Hongxiangsu pear can be kept above 230 g with a regular fruit shape.

Because the local day-night temperature difference is small and the altitude is low, Hongxiangsu pear colors poorly under natural conditions. To improve fruit coloration of Hongxiangsu pear, management should maintain good ventilation and light penetration within the canopy, and during the coloring season measures such as leaf removal, fruit turning, laying reflective film, and spraying monopotassium phosphate in July should be adopted to promote coloration. Otherwise only the sun-exposed side of the fruit will be slightly red. Bagging should be done about 20 days after full bloom, and transparent plastic bags must be used; paper bags or no bagging give unsatisfactory coloration and a rough, uneven fruit surface. After the fruit ripens, it can be picked and stored with the bags on.