Introduction and cultivation techniques of Emerald Pear in the area of abandoned Yellow River

1. General situation of introduction sites

Xiangshui County, located in the northeast of Jiangsu Province, is located in the warm monsoon climate zone and belongs to the flood area of the old route of the waste Yellow River. the annual average temperature is 13.9 ℃, the annual precipitation is 912mm, the extreme highest temperature is 38.7 ℃, the extreme lowest temperature is 17 ℃, and the frost-free period is 220 days. the precipitation is mainly concentrated from May to September. The introduction demonstration garden is sandy loam, deep soil layer, medium fertility, good air permeability, PH value of 7.2. 1440 emerald pears were introduced. Three hundred and fifty golden pears were planted in the spring of 2001. the row spacing was 2 × 3 m. Golden pear was used as pollination tree according to 4 ∶ 1.

2. Introduction performance

The main results are as follows: 1. After 6 years of observation, the young trees grow vigorously, the tree posture is upright, the branches are strong, the natural height of 6-year-old trees is more than 4m, the average crown width is 3.1m, the germination rate is 79%, and the branching ability is weak, mainly with short fruit branches. The fruit of long and middle fruit branches is auxiliary, and it is generally not easy to form flower buds in the same year, but it is easy to flower after branch drawing, with a large number of flowers and strong high yield. it begins to flower in the second year after planting, and the average yield per mu is 530kg in the third year, 1260kg in the fourth year, 1960kg in the fifth year, and 2360kg in the sixth year. The fruit is flat and round, with an average single fruit weight of 260g, light green pericarp, small fruit spot, smooth fruit surface, low fruit rate, delicate meat, more fruit juice, medium fruit core, 13.1% soluble solids, sweet taste, few stone cells and high quality.

2. In the phenological period, the emerald pear sprouts in late March, blossoms in the first ten days of April, blossoms in the middle of April, ripens at the end of July and leaves fall in the middle of the month.

3. Adaptive emerald pear has strong adaptability to high temperature and high humidity, and its resistance to scab, ring disease and pear planthopper is significantly higher than that of "Sanshui" pear. The initial fruit stage of emerald pear is easy to crack from fruit expansion to maturity, and the fruit cracking rate is as high as 36%, especially in the case of long drought and rain. with the increase of tree age, the fruit cracking situation decreases year by year, and the fruit cracking rate of 6-year-old trees reaches 7.8%.

3. Main cultivation techniques

The main results are as follows: 1. The planting holes with 1m in length, 1m in width and 0.8m in depth were dug in winter, and the surface work and the subsoil were stacked respectively when digging the hole, and the rotten organic fertilizer 40kg was applied to each hole. The topsoil was under and the subsoil was filled at the top in early spring, and the backfill height exceeded the ground 15cm, and it was planted in early spring next year.

2. Fertilizer and water management 1-year-old 2-year-old young trees apply thin fertilizer frequently, fertilize once after sprouting and spreading leaves, and apply available nitrogen fertilizer urea 0.5kg each time to promote the growth of young trees and rapid crown formation. Application of rotten chicken manure 25kg in autumn, addition of N, P and K compound fertilizer 1kg per plant, application of multi-component compound fertilizer 1~1.5kg during fruit expansion period, application of rotten chicken manure 30kg and multi-component compound fertilizer 1kg per plant at the end of September, timely irrigation after fertilization to promote timely absorption and utilization of fertilizer by fruit trees, timely irrigation should be done in case of drought from sprouting to fruit expansion period. Rain Water should do a good job of drainage in sufficient season in summer and autumn.

3. The upper layer happy shape is adopted in the shaping and pruning, which is mainly done by position, light truncation and thinning. In the young tree stage, except for the truncated central trunk and the extended main branch, the rest of the branches are as long as possible, cut as little as possible, and sparse as many branches as possible. Make use of the valuable overgrown branches and dorsal branches as far as possible, transform and make use of the opening angle of pulling branches, the pulling should be completed by the end of May, the height of the fixed trunk is 0.8m, and 4 main branches are selected in the first layer. 2-3 lateral branches were cultured on each main branch, and the basal angle of the main branch of the young tree reached 70 degrees. The distance between the second layer main branch and the first layer main branch is 1.2m, leaving 2 to 3 main branches, the base angle of the main branch is up to 60 degrees, and the head is happy after the main branch is selected. Pay attention to summer pruning, this tree shape and pruning method can promote the formation of medium and short fruit branches and ensure high yield of early fruit.

4. The fruit setting rate of Lvshu pear is high, with 3-8 fruits per inflorescence and 11 fruits in individual inflorescences, so it must be strictly thinned. In early April, the flower bud scales are loose, and when the flower buds are white, remove the weak flower buds, cut off the upper part of the flower buds, and retain the long leaves of the leaf buds to increase the effective leaf area. After physiological fruit drop, small fruit, pest fruit and erect fruit were removed, only one fruit was left in each inflorescence, fruit spacing was 15~20cm, fruit thinning of 6-year-old tree was completed at the end of April.

5. Pest control in Xiangshui area during the dry season in May, emerald pears are prone to pear planthoppers, aphids and other leaf-eating pests, such as stinging moths, star caterpillars, pear net bugs and other leaf-eating pests. The main pests that damage the fruit are pear bees and pear heart borer, and the diseases are mainly ring disease, brown spot, iron deficiency and zinc deficiency. The disease can be controlled alternately with 50% tuibute 800-fold solution or 50% mancozeb 600-fold solution. Pests can be treated with imidacloprid or aphid pyrethroid pesticides; zinc fertilizer and ferrous sulfate can be applied with zinc deficiency and iron deficiency.