Scientific name Akiko pear systemPyrus ussuriensis Maxim., alias perfume pear, heart pear, frozen pear, pear, family Rosaceae pear genus Prus.
The geographical distribution of soft pear belongs to the varieties of the Autumn Pear system. There are 4 cultivated species (systems) of pear trees. They are the white pear system.
Sand chrysanthemum system, autumn chrysanthemum system and Western pear system. The first three systems are all native to China and have a long history of cultivation. 1. White pear system P. bretschneideris representative varieties are: Laiyang in pear, duck pear, snowflake pear, autumn white pear. Long handful of pears, zhongshan crispy pears, Qixia large perfume. Avocado. Golden pear, Jinchuan sydney pear, Korla fragrant pear, winter fruit pear, apple pear. Jinfeng pear. Early crispy pears, etc. It is mainly distributed in Shandong. Hebei and other north China provinces, northwest, Liaoning and Zhuanhe River basin also have a small amount of cultivation, is China's cultivated pears in the wide distribution, the largest number, the best crystalline species.
2. Pear system P. serotina: Cultivars are available. Twenty centuries. New Century. Atago, Toyomizu, Nagashiro, Yukimizu. Kikusui, Kansanyoshi, etc., introduced in recent years, there are varieties of Japanese and Hansha chrysanthemums with gold. Crystal, Huashan. Round yellow. Bright yellow and full of trees. Aiganshui, Nanshui, Jade, Early Golden, Autumn Yellow, New High, Emperor. Li Wang, Sweet Pear, Sweet Spring. Finish the show, like water, etc. It is mainly distributed in the southern provinces south of the Huai River and the Yangtze River Basin.
3. Akiko pear system P. ussuriensisi culti culti have. Kyo white pear. Crispy wood pear, nanguo pear, red nanguo, ann pear (sour pear), face sour pear, flower cover pear, soft pear (perfume pear) and so on. It is mainly distributed in Anshan, Haicheng and Liaoyang areas of Liaoning. Jilin. It is also cultivated in Inner Mongolia and parts of northwest China. Among them, soft children belong to the ancient excellent local varieties of Lanzhou. Cultivated for more than 500 years, it is known as the "Eight Pears" of Longshang (Soft Pear, Winter Fruit Type, Crispy Wood Type, Eight Plague Pear, Pig Head Pear, Qi Pear. Long handful of pears. Apple pear) is the best of the varieties. In 1993, as one of the business cards of Lanzhou's "Famous City of Guaguo", it was rated as "China's Time-honored Brand" by the Ministry of Trade. 4. Western pear system P. cowwnis: Cultivated varieties include pear, red pear, red Cowmys. Early red Cormes, red sweet pear. Red Anjiu. Gourd pears, etc. In recent years, different varieties have been introduced and cultivated in various pear-producing areas in the north.
Morphological characteristics soft pear tree body tall, tree-shaped opening, in the natural growth state, the tree shape is more like a pyramid shape. The main trunk is greyish black, and the perennial branches are grayish brown. The branches are dense. The thin surface droops. Ye Dan is oval, the light sheet is extremely pointed, and the base is truncated or nearly circular. The edges are serrated and serrated. The flowers are white, and 5-to-7 flowers form an umbrella inflorescence. The fruit is nearly spherical , yellow or green with a reddish halo. The flowering period is early to mid-April, and the fruit ripening period is from 10> to November.
The cultivars of the ecological habit pear tree are all light-loving. Hi Wen. Hardy, drought-resistant, waterlogged, salt-tolerant, and more adaptable to the external environment than apples. Areas with minimum temperatures above -25C in winter can safely overwinter. The root system is well developed, the adaptability to the soil is very strong, and the mountainous. Hills, sand barrens, depressions. Both saline and alkaline soils and red soils can grow and bear fruit, and it is advisable to choose flat land with deep soil layer and good drainage or gentle slope mountain to build a garden. Sandy loam soils are preferred. It is particularly resistant, second only to Portugal. Soft children's trees are strong, long lifespan, long economic utilization years, such as Lanzhou Gaoma County Shiyong Town has so far been on the dry field tree age of more than 300 years old pear garden, there are soft pear and other fruit type about 4,000 trees, trunk thick. 3 people hugging. And after hundreds of years of vicissitudes, but the canopy is still lush and dramatic. Living things. The maximum plant yield can reach more than 500 kg. The average plant yields 250 kg, and the total annual output of pears and fruits is about 1000 tons. Soft pears bear fruit early, 4 to 5 years after planting, and enter the fruit hanging period in 8 to 10 years. Mainly short fruit branch results, high fruit set rate, good yield performance, 20 ~ -30 years old tree plant yields about 250 kg, the size of the year is not obvious, and easy to renew and rejuvenate.
The average fruit weight of the soft pear is 127 grams, and the large one can reach more than 300 grams, and the fruit surface is yellow and green when ripe. The green is reddish, the skin is thicker, the flesh is hard, the taste is sour, and there are more stone cells. The storage result is waxy yellow, and after a month the fruit ripens and begins to soften. From yellow to black, the flesh is rigid. The flavor is juicy, cool and sweet. The fruit contained 13.4% soluble solids. Organic acid 0.6%, vitamin C 1.2 mg / 100 g, also rich in sucrose, glucose and other components. The nutritional value is extremely high, and it has clear heat and detoxification, moisturizing and coughing, and raw and refining the pharynx. Cures fever and cough. Disorderly body to get rid of diseases. It is a fruit with both dietary therapy and antidotes, such as reducing fire, curing wind and cold, detoxifying sores, moisturizing the lungs, aiding digestion, and relieving alcohol. A "share of the solstice rate. rule. Aged into ice balls, when eaten, it needs to be placed in a warm place to dissolve, or put into clear water, because the water temperature around the fruit surface drops sharply, after about half an hour, a large ice layer will form around the fruit surface, gently knock off the ice shell, .
The pulp becomes a bag of juice, and the slurry is very much. The taste is sweeter than honey, and rich in wine, tearing the skin when eating, sucking with the mouth, a package of sugary honey juice dissolved in the mouth, fragrant, refreshing. Therefore, soft pears are also called "perfume pears". Soft pears can also be processed as "soft pears. Juice", is a good drink.
Breeding and cultivation
1. Seedling breeding: seedlings are grafted and propagated, and the rootstocks have Du type, mountain pear, bean pear, sand poly, etc.: dwarf anvils Selected 8 series of rootstocks in China such as K9 and KI3. K21. K28. K31 shows strong dwarfing or semi-dwarfing characteristics, strong affinity with pears, and grafting heals well.
(1) Station cultivation: Lanzhou area - generally anti-salinity. Du Fan, who has strong disease resistance, is a rootstock. Due to the developed main root, if the root breaking measures are not taken, there are few well-developed side roots, so in order to promote multiple side roots, Du pear seedlings should take root-breaking treatment when growing to 40 cm high, and at 20 cm at the base of the seedling line spacing in the seedbed row, insert it at a 45" angle with the ground with a "broken root shovel" or straight iron eye to cut off the main root. After the root is broken, it is necessary to water the root in time, topdress and cultivate.
(2) Grafting: grafting can be grafted and budded, and autumn budding is mostly used for a large number of propagated seedlings in production. Because the rootstock and scion formation layers are required to be active during the bud joint, that is, the period when the xylem and phloem are easily separated, the bud joint is better in early and mid-August, and the "T" shaped bud joint or the wood bud joint is mostly used. The ears should be harvested on young trees with strong body and good yield. The grafting part should be appropriately raised during grafting, and it should generally be grafted more than 30 cm from the ground by anvil surgery to prevent the occurrence of black shin disease (dry base wet rot disease). In addition, special attention should be paid to exposing the buds when plastic binding.
(3) Post-pick-up management: (1) Reconnection: 10-15 days after bud picking, check, live buds are fresh, petioles fall at a touch, and unviated ones are patched up in time. (2) Anvil cutting, removal of germination: The seedlings after the buds are cut before germination in early to mid-April of the following year, and the anvil is cut from 0.5 cm on the buds when the anvil is cut, and the binding is lifted. After germination, the germination U that grows on the rootstock should be erased in time to ensure the normal growth of the buds. Pillar of the State. Binding: Soft pear seedlings have the characteristics of twisted growth, easy to length and bend down, so when the bacteria are about 60 cm high, they should stand on a pillar to tie the new shoots, and the binding can also prevent being blown by the wind. (4) Field management. Seedlings grow 2 times in the early stage of growth, mainly nitrogen fertilizer, 10 kg of urea per mu per time, and timely irrigation after application: in the later stage, 0.3 potassium dihydrogen phosphate can be sprayed foliarly for 1 to 2 times, and weeding is carried out in time to ensure the growth of seedlings.
2. Planting and building a garden:
(1) Same-site selection: Soft children gather strong trees, early results, high yield, in order to achieve its high yield, high quality, high efficiency purpose, it is best to choose a high content of soil organic matter when building a group. The soil layer is deep and the transportation is convenient. Build a garden in a place where irrigation is convenient.
(2) Variety selection: Soft pears have a long history of cultivation and more natural variations, including red soft children (red perfume) and sharp soft children. Green skin soft child, hemp skin soft child. Many varieties such as white-skinned soft children, especially white-skinned soft children, have the best quality and the best yield performance, and should be used as the first choice in cultivation.
(3) Pollinator tree configuration: Lanzhou soft child poly into triploid varieties, self-flowering knot strength is not strong. In order to improve the fruit set rate and achieve the purpose of high yield and high quality, when building the garden, it is necessary to configure a pollination tree, you can choose winter fruit pear, Beijing white pear, Hongxiao pear, the configuration ratio is generally in the large area of the use of the determinant formula 4:1 is appropriate, that is, every 4 rows of replanting, with pollination tree I row.
(4) Basal planting: Spring cutting is carried out after soil dissolution and aging until the seedlings germinate. Generally, the row spacing (3~4) bundle X (4~5) meters. Before planting, excavation and colonization are large, and the hole depth is 0.8 to 1 meter. Diameter 0.8 meters, each hole applied 10 kg of decomposed organic fertilizer (sheep manure, etc.) and 2 kg of calcium superphosphate mixed with the upper layer of mature soil and filled into the lower layer of the pit, filled to 2/3 of the time of the solid irrigation, to be underwater seepage after cutting seedlings, the seedlings stand upright in the center of the pit, the root system stretches around, while filling the soil on the side of the seedlings, so that the roots stretch. After planting, watering, after the water is slightly dry, loosen the soil in time and spread mulch film to increase the ground temperature and promote new roots.
3. Shaping trimming:
(1) Basic tree shape: tree shape - generally adopt the middle crown trunk thinning layer: the tree height is 3.5 to 4 meters. The stem height is about 1 meter, the crown diameter is 3 meters, and the whole tree has 6 to 7 main branches. Arranged in three layers. The first layer of main branches 3, the inner distance of the layer 40 cm, the azimuth staggered 120", each main branch cultivates 3 side branches, the first side branch is about 50 circles away from the main trunk, the second side branch is 30 cm away from the first - side branch, the side branches are distributed obliquely on both sides of the main branch, and the upper resulting branch group: 2 main branches in the second layer, and 2 branches are cultivated in each main branch. The spacing between the first layer and the second layer is about 1 meter, and the third layer has 1 to 2 main branches. The spacing between the second and third layers is about 60 cm, and there are no side branches on the main branches of the second and third layers, and various fruiting branches or fruiting branches are born on them. All main branches are angled around 75". This tree structure is simple. Suitable for medium dense planting. Acre cut 56 tree structure.
(2) Pruning in the year of colonization: The finished seedlings should be dried after planting in the spring, that is, they should be shortened at a height of 1.2 meters of the seedlings. The cut F should have more than 8 full bodies, which is called a plastic belt. After the branches are ready, select 4 to 5 long branches in the plastic band. Selected as the central leader branch and the first layer of main branch, all the buds below are erased with the plastic band. When shearing, the branches with strong growth at the top are first selected as the central leadership stem, and the three long branches with uniform distribution and suitable angles are selected as the first main branches. And short shear at the full bud of 50 to 70 cm, pay attention to the main branch shear mouth bud to leave the outer bud.
(3) Pruning in the second year: Still leave the top cut strong branches as the central leading branches, and cut short at 60 cm full of buds. The first layer of the main branch left 50 cm full of outer wood short shear, so that it continues to extend outward to expand the crown, the well on the main branch to select a suitable position of the side branch, leaving about 50 cm long, the rest of the school slowly put the shear, left as a preparatory branch.
(4) Pruning from the third to the early stage of the results: In the pruning technology, we should mainly grasp the four points: (1) The cultivation of the central leadership stem: When pruning every year, we must choose the branches with stronger growth at the top. Continue to cultivate the central leadership stem, cutting the length of 60 cm. The cut is selected in the reverse direction of the previous year's cut. Every year. Allow the center to dry to a curved shape. (2) Continue to cultivate the main and lateral branches: select the main branches and side branches according to the distance between layers, and select the full buds in the main and lateral branches to extend the branches. And leave more branches on the main branch, and control the long branches of the strong straight disciple. Opening angle. At the same time, pay attention to the cultivation of lateral branches, which are at a 45" angle to the main branch and extend in the direction of the main branch. @ Adjust the master-slave relationship: that is, the same layer of the main branch should be thicker than the main branch, and the lower main branch should be thicker than the upper main branch. The main branch should be thicker than the side branches. (4) Timely opening of the main branch angle: when the main branch angle: spend hours, the use of rope pulling, support and other methods. Open the main branch angle to about 75", if the main branch is thick, you can open three saws behind the base of the main branch. Then pull it open with a wire and pad the wire buckle part on the branch. So as not to let the iron ring fall into the cortex. Do not pull into a slingshot shape.
(5) Pruning at the first fruit stage: Soft pears begin to bear fruit 4 to 5 years after planting, and the pruning task in this period is to strengthen the cultivation of fruiting branches on the basis of maintaining the cultivation of bone F branches at all levels, and rationally use the auxiliary nutrient branches. Enter the harvest period as soon as possible. (1) Cultivation of fruit branches: Fruit branches are born on backbone branches at all levels and towards the branches. Result units with more than 2 branches. Small fruiting branches with 2 to 5 branches are divided into small fruiting branches: those with 5 to 15 branches are medium-fruiting branches: large fruiting branches are considered to be large-fruiting branches when there are more than 15 branches. There are three ways to cultivate twig groups: One is the first release and then shrink method, which can cultivate small fruit twigs. The second is the method of continuous release and re-contraction. The long branches with strong growth are continuously slowed for 2 to 3 years, and after the results, they can be retracted and pruned according to their space, and can be cultivated into large and medium-sized fruiting branches. The third is the compulsory surgery method, one is to put the upright branches with room for development. Strong branches, competitive branches. By bending, pulling. press. Circumference and other summer pruning measures, talk and growth. Promote the formation of flowers. This method can cultivate small and medium-sized fruiting branches. (2) Control transformation of auxiliary branches: enter the fruiting period. Some of the auxiliary branches between the layers or on both sides of the main branches have no space to grow, and those who are too dense and spaceless are removed. There is room for the use of retracted or sparse branching methods, to go strong and leave weak, to stay straight and oblique, and transform into middle. Small fruit twig group, thread fruit.
(6) Pruning at the full fruit stage: The shaping task of entering the dry fruit stage has been completed, and the main task is to extend the full fruit period and produce high yields for consecutive years. High quality, therefore, adjust the contradiction between growth and results, improve ventilation and light transmission conditions become the main task of pruning. (1) Maintain a moderate tree posture: its basic criteria are that the canopy periphery is slightly 30 to 40 cm, and the short and medium branches are robust, the whole tree flower buds are full and appropriate, and the ratio of growth branches to fruiting branches is 3:1; the fruiting branches are younger, and the small and medium-sized fruiting branches account for 80%-90%. Focus on the internal adjustment of the resulting branch group. Do the "three sets of branches" pruning, that is, into flower branches. The three types of fruit branches and growth branches each account for 1/3 of the alternating results. Update Rejuvenation. The twig age of the resulting group is maintained at a young state of 3 to 5 years. (2) Change the ordinary wind and light transmission conditions: during the fruiting period, due to the large canopy, it is easy to compete for light. The phenomenon of competing for nutrients, the sexual harmony of light and black deterioration, and the weakening of twigs. Lose the ability to update results, and when trimming, you have to dry the head and be happy. Second, it is necessary to remove the large branches that are too dense in the upper part of the canopy. Strong branches. Third, it is necessary to remove the overly dense branches in the periphery in a timely manner. Strong branches. Four to go back to the group. Remove secondary branches between layers and between main branches. Finally reach the canopy up and down. The light and black are uniform inside and out.
4. Soil fertilizer and water management:
(1) Soil management: Good soil is the basis of abundant production. Only by increasing soil organic matter, improving soil structure, and creating a good environment for root growth and absorption can stable yield be achieved. High yield. Quality purpose. Soil improvement is carried out by two methods: (1) Deep soil layer turning: it can be carried out every autumn when organic fertilizer is applied. Fertilization is carried out by annular furrows under canopy projection, with a depth of about 40 cm, and deep turning with the expansion of the canopy outwards and fertilization every year, which can deepen the root distribution layer. Enhances root growth and absorption. It is also possible to use the autumn garden to spread organic fertilizer on the ground and turn the whole garden deeply. Depth 25 to 30 cm, even ask the surface of the dry rod. Weeds, fallen leaves and organic fertilizers are all turned below the ground, decomposed to form male phytic acid, etc., which has a good effect on improving cold soils. (2) Intercropping and intercropping: Green manure crops such as legumes are planted between orchard rows, which are deeply turned into the soil in summer and autumn, which plays a role in increasing organic matter and improving soil fertility.
(2) Orchard fertilization: (1) base fertilizer; generally applied after the harvest of pears in mid-to-late October to the beginning of November before leaf fall, early application is conducive to root growth and nutrient absorption, improve the level of nutrient storage in tree rest. Lay the foundation for the growth and flowering of new boxes the following year. In the orchard at the peak of the fruiting period, the base fertilizer can be changed to the ditch to be applied to the ground, and the whole garden is turned deeply after application. Water immediately. (2) Topdressing: Mainly according to the characteristics of fertilizer demand at each growth stage of pear trees, timely supplement the required quick-acting fertilizer. Nitrogen fertilizer is mainly used before germination to flowering: nitrogen fertilizer is applied in time during the fruit setting period after flowering, and then an appropriate amount of phosphorus fertilizer is added to solve the contradiction between vegetative growth and reproductive growth: which is large to the flowering division stage is still dominated by nitrogen fertilizer, with phosphorus. Application of potassium fertilizer: Phosphorus and potassium fertilizers are the main ones in the late growth period of the fruit. (8) Topdressing outside the root: 0.3% urea is sprayed in the canopy in stages. 0.3% potassium dichlorophosphate solution.
5. Disease and pest control: the main diseases of soft pears are pear tree black shin disease, pear tree rot disease, etc.: the main insect pests are pear small heartworms. Type wood lice. Red spiders, aphids, etc.
(1) Pear tree black shin disease: that is, dry base wet rot disease. (1) Symptoms and pathogenesis: The disease first occurs on the joint of the grafted part of the base of the trunk. It is manifested by a brownish appearance of pericontal tissue and gradual immersion into the forming layer. First, the diseased area is spotted and the dry diameter becomes thinner. Posterior dry shrinkage depression. Necrosis is formed, and in the later stages, the diseased part and the healthy part produce a rift. After 1 to 2 years of soft pear disease, the branches and leaves appeared in the same year, and the whole tree died. After more than three years of growing trees, the plant gradually weakens and the leaves are small and pale. In autumn, the leaves turn purple-red, the leaves fall off early, the fruit develops slowly, becomes a small berries, and the whole plant dies after 2 to 3 years. High temperature, high humidity is the main condition of the disease. (2) Prevention and control method: A seedlings are selected from disease-resistant Du pear anvils, and the part of the graft building cannot be less than 30 cm. B. The finished seedlings should not be planted too deeply. Be sure to expose the cutting board to the ground more than 30 cm. C. During high temperature periods, it is free to accumulate water in Kepan. D. Remove weeds and keep the base of the trunk dry. E. Avoid main trunk trauma and prevent germs from being infected. F. The garden is built from the wood of the Du Pear Station, and after 1 to 2 years of growth, the soft pear varieties are grafted at the high branch level. G drug prevention and treatment, mainly to scrape the scars, scraping the scars with 843 rehabilitation agents, rot Biqing, 75% bacillus qing 200 times liquid for application, the prevention and control effect is better.
(2) Orange tree chest rot disease: (1) symptoms and pathogenesis; the main cause of the disease is in the main branch, side branch and branch right part of the pear tree. At the beginning of the disease, the lesions are soaked, slightly lowered, and the tissues of the diseased part are soft. Brown juice flows out, there is a fine taste, the later cortex decays, the water loss depression is gradually lost, there are seams at the junction of the diseased part, and finally a black little finger conidia grows, and when the rain is mixed, the pale yellow spore horn is formed. (2) Prevention and control methods: people strengthen the management of technical training and enhance the tree potential. Improves disease resistance. B. Protect the tree body from various mechanical damage and prevent smoke. In the spring, the scars should be scraped in time, and after scraping, apply with 1:3 times liquid of rot biqing or cure rot. Applying twice in spring and summer has a better effect.
(3) Small pear: heart-eating insects: (1) Infestation and occurrence rules: larvae harm soft pears and other pear fruits, mostly from zun, moths at the stem, and go straight to the heart of the fruit after mothing. Later in high humidity conditions, it is blackened and decayed around the borer hole. It is commonly known as "black cream disease" and "bean paste trap". Makes the fruit lose its edible value. Pear trumpetworm occurs in 3 generations per year in Lanzhou, with old mature larvae overwintering under the trunk of pear branches, at the cracks in the root neck, and under the surrounding topsoil. The peak of overwintering adult feathering is in mid-to-late April, and the feathered adults will lay their eggs in peaches. Plum and other fruit trees on the new shoots. After the eggs hatch. The first generation of larvae are infested with fruit or moth plants. The apricot fruit fell off after being injured, and the peach broke after being slightly injured. In mid-June, the second generation of F larvae hatched, mainly endangering apricot fruit, and the worm fruit did not fall off after the moth fruit. In early August, the third generation of larvae hatched, at this time mainly for the pest of pear fruit, after the moth fruit has been endangered until September after the larva mature, the fruit to find my wintering place. The autumn larvae that harm pear fruit have generational overlap, and some underripe larvae are stored with the fruit, resulting in rotten fruit.
(2) Control method: A. Before the overwintering larvae are defruited, the trunk base is slightly tied to break the sack pieces and other soft objects, luring the larvae to overwinter in the lashing, and then burned in a concentrated manner. B. Zero. Early spring: Scrape off the old warp skin thoroughly. And concentrate on burning to eliminate subcutaneous overwintering larvae. C. Peach, Lee. Apricots, pears mixed in the orchard. Spring focuses on grasping peaches. apricot. Control of medium-sized small heartworms on fruit trees such as Plum. generation. The second generation of larvae is the initial stage of pest. The canopy is sprayed with 10% Uranus emulsion 6000 times liquid or 20% extinguishing emulsion 3000 times liquid. D. When the three generations of larvae in the soft season are used as harmful pear fruits, they can spray 50% dauphin emulsion 2000 times liquid. 20% Harvest Chrysanthemum Shield Emulsion 1000 times liquid. Sprayed every 10 days, the drug is connected twice, and the prevention and control effect is better.
(4) Poly wood wind: (1) Damage and occurrence law: mainly adult insects, nymphs suck sap on pear leaves, young shoots, shoots and fruits, when the leaves are seriously damaged, it can lead to leaf fall, and the autumn larvae secrete mucus on the leaves and fruits. A black mold river is formed on the surface. No: but affects the photosynthesis of the leaves. And it makes the quality of the fruit degraded. Yield: The amount is reduced, which directly affects the commodity value of pear fruit. Pear lice occur in Lanzhou for 3 to 4 generations per year, with adults overwintering in deciduous, mottled and bark crevices. Overwintering adults sting early and lay their eggs in late April. Nymphs appear in early May, and concentrate on young leaves as pests, and later generations mostly suck on the back of the leaves, and secrete a little liquid, the generations overlap from July to August, the pear leaves and fruits are the most seriously affected, and the overwintering adult insects appear in September. (2) Prevention and control method: After the leaves of the pear tree fall, the stump leaves and weeds of the pear garden are completely removed and burned in a concentrated manner. B. Scraping off the old bark of the pear tree in early spring, .
Eliminate overwintering adults. C. Pharmaceutical prevention and treatment, mainly grasp the three key periods. First, in early April, the teeth just germinated and did not move, which is the peak period for adult worms to emerge. Spray 5 pomedo stone conjugates can kill insects and eggs in the whole tree: the second is that the pear blossoms appear budding in mid-to-late April, but spray 20% inulin emulsion 3000 times liquid when it is not open, which can take into account other pest control, and the control effect is better: the third is after the soft pear falls, that is, in the first generation of egg hatching in mid-to-late May, spray 20% pyrethroid emulsion £000 times liquid.