Cultivation Techniques for the High-Quality Mid-Season Pear 'Huangjin'

Variety Characteristics The Huangjin pear was bred in South Korea by crossing '20th Century' and 'Niitaka', and is one of South Korea's main pear cultivars. It was introduced to China in 1997. The fruit is oblate, with a single fruit weight of over 350 grams and a maximum fruit weight of 500 grams; at maturity the skin is yellow-green, turning golden yellow after a short period of storage. The skin is extremely clean (bagged fruit is golden yellow at maturity and appears translucent), the lenticels are large and sparse, the flesh is slightly soft and juicy, white in color, with very few stone cells, an edible rate of 95%, and a sugar content of up to 14.70 degrees. The flavor is sweet with aroma, unique in flavor and of excellent quality. The fruit ripens in the Jinan area in early to mid-September. It stores fairly well, with the flavor unchanged after 2 months of cold storage. This cultivar sells very well in Southeast Asian markets at extremely high prices, making it a mid-season cultivar with great development potential. This cultivar bears fruit early and has good productivity, fruiting mainly on spurs and axillary flower buds. Young trees bear fruit in 2 years and reach high yield in 3-4 years; top-grafted trees can reach a maximum yield of 60 kg per tree in the second year.

Planting and Orchard Establishment This cultivar is highly adaptable, tolerant of poor soil, relatively drought-resistant and cold-resistant, grows well when cultivated on mountain slopes, hills and plains, and is suitable for cultivation in various regions. Before planting, deep plowing and soil improvement should be carried out along with the application of high-quality farmyard manure, and then planting trenches should be dug in preparation for planting; high-quality vigorous seedlings should be selected, with a spacing of 2 m x 3 m to 4 m; planting can be done in either spring or autumn, but spring planting is preferable. To ensure high quality and high yield, cultivars such as 'Niitaka' and 'Fengchan' should be planted as pollinators, with pollinizer trees configured at a ratio of 6-8:1.

Fertilizer and Water Management Huangjin pear orchards should focus on building up soil fertility. In autumn, base fertilizer should be applied together with deep plowing and soil improvement. Base fertilizer should be applied early, generally completed before the end of October, at 3000-4000 kg of farmyard manure per mu; topdressing is generally carried out 3-4 times a year, at the following times: before bud break, after flowering, and during fruit enlargement. Nitrogen fertilizer should be the main fertilizer in the early stage, and compound fertilizer in the later stage; foliar topdressing should be carried out together with pesticide spraying, with nitrogen in the early stage, phosphorus and potassium in the middle stage, potassium before fruit harvest, and appropriate nitrogen supplementation after harvest. Irrigation should focus on the periods before flowering, after flowering and during fruit enlargement, and can be combined with fertilizer application and irrigation, while paying attention to waterlogging prevention and water control before harvest.

Flower and Fruit Management The flower and fruit management measures for Huangjin pear mainly include flower and fruit thinning and bagging. Flower and fruit thinning should be carried out from the inflorescence separation stage to the initial flowering stage, generally leaving 1 inflorescence every 20-25 cm and removing all other inflorescences; fruit thinning begins 1 week after petal fall and is completed within 1 month, leaving more fruit on vigorous trees and fewer on weak trees; bagging cultivation is basically the same as for apples, except that the bags do not need to be removed before harvest, and the paper bags can be harvested together with the fruit.

Training and Pruning The ideal tree form for Huangjin pear is the modified spindle shape. Young trees should be pruned lightly and left to grow, with attention to combining summer pruning with winter pruning; for 1-3 year old trees, as many nurse branches as possible should be retained, and in summer flower formation should be promoted through techniques such as leaving branches unpruned and bending them, and pinching, with the characteristic method being repeated pinching of strong vigorous new shoots; during pruning, attention should be paid to controlling through the selection and retention of branches.

Pest and Disease Control Huangjin pear is relatively resistant to pests and diseases. The main pests and diseases include pear scab, pear rust, and pear psylla. Control should adhere to the principle of prevention first and integrated control. On the basis of strengthening management and improving tree resistance, biological and low-residue pesticides should be sprayed for control: (1) before bud break, spray 5 degrees Baume lime sulfur mixture; (2) before flower bud swelling, spray insecticides such as 2.50% Baode EC at 2000 times; (3) during the young fruit stage, spray 200 times Bordeaux mixture at double strength; after early to mid-June, switch to spraying pesticides such as carbendazim.