Detailed Explanation of Key Cultivation Techniques for Emerald Pear

Emerald Pear, also known as Zhongli No. 1, was bred by the Zhengzhou Fruit Research Institute of the Chinese Academy of Agricultural Sciences through hybridization between Shinseiki and Zaosu pear. It is one of the early-maturing pear varieties with better overall traits currently available.

I. Characteristics. This pear variety has strong growth vigor, a high germination rate, medium branching ability, and a small branching angle. The leaves are long ovate, flat, with sharp and dense serrations along the leaf margins. It has strong early fruiting ability; high-grafted trees can form flower buds in the same year and bear fruit the following year. It has a high fruit-setting rate and good yielding ability, with a habit of fruit setting on axillary flower buds, and in the full bearing period, short fruit spurs are the main bearing sites. The fruit is large, nearly round or oblate, with an average single fruit weight of about 296 grams and a maximum fruit weight of about 485 grams. The fruit surface is smooth, the fruit dots are medium-large, and the color is emerald green; bagged fruit are yellow-white. The fruit stalk is thick and short, the calyx cavity is shallow, and the calyx segments remain. The flesh is milky white, crisp and tender in texture, with few stone cells, abundant juice, and a sweet taste with slight fragrance; the soluble solids content is 11.8%. In Botou City, Hebei Province, it blooms around April 10 and matures in mid-July.

It has strong stress resistance and disease resistance, and does not have strict requirements for environmental conditions; it is particularly strongly resistant to ring rot, scab, and dry rot. However, in some years, fruit cracking is relatively severe.

II. Management Key Points

1. Training and pruning: For top grafting to replace the canopy on large trees, single-bud side grafting and cleft grafting can be used. The tree shape should maintain the original tree structure; because this variety has strong growth vigor, an open-center tree shape should not be used. In the first winter after top grafting, pruning should be light, and as many branches as possible should be retained. Later, as the canopy expands, excess branches should be gradually removed over 2-4 years. In summer, methods such as branch bending and branch twisting are used to adjust branch angles. For trees just entering the heavy fruiting stage, thinning branches to clear the interior is the main practice; severe and hasty renewal pruning should be avoided to prevent excessive vigor and adverse effects on flower bud formation.

2. Artificial pollination and flower and fruit thinning. Artificial pollination can ensure well-formed fruit shape, large fruit, and good quality. Yali, Huangguan, and Huangjin pears can all be used as pollinizer varieties. Flower thinning is done to save nutrients, exchange flowers for flowers, and achieve high yields year after year; fruit thinning is done to control yield and ensure quality, thereby ensuring benefits. Flower thinning is carried out from inflorescence emergence to full bloom, leaving 1 inflorescence every 20-25 cm and removing all the rest; fruit thinning is completed from late April to mid-May, leaving 1 fruit every 25-30 cm.

3. Fruit bagging. Producing high-quality, premium pear fruit requires fruit bagging. The bagging time is from mid-May to early June, and three-layer paper bags with an inner layer of cotton paper are preferred. Before bagging, an insecticide and fungicide must be sprayed once to prevent pests and diseases from being bagged inside; bag after the spray liquid dries.

4. Reasonable fertilizer and water management. A sufficient supply of fertilizer and water must be ensured. Apply 5000 kg of organic fertilizer, 20 kg of diammonium phosphate, and 25 kg of potassium sulfate per mu as autumn base fertilizer. Before bud break and after fruit harvest, nitrogen fertilizer should be the main topdressing; after flowering and during fruit expansion, compound fertilizer should be the main topdressing, applied 2-3 times. Irrigate thoroughly in combination with fertilization. From after petal fall to before mid-June, ensure sufficient water supply; after late June, irrigate cautiously.

5. Pest and disease control. Before bud break (mid-March), spray the whole orchard once with 5 degrees Baume lime sulfur mixture. During the growing season, spray 8-10 times according to the dynamics of pest and disease occurrence. Generally, fungicides such as polyoxin, Fuxing, Shigao, and Junlimie are used to control bagged fruit black spot disease and black spot disease, and insecticides such as abamectin, imidacloprid, and Lesiben are used to control pear psylla, yellow mealworm, and mango mealybug.