1) One hole has many kinds, and two plants are grafted. Measures to protect seedlings per plant to ensure garden cleanliness. When sowing, sow 5 ~ 7 seeds with a diameter of 50 cm according to the standard. After the emergence of seedlings, select the seedlings with strong growth and graft them at the intermediate seedling stage. Generally, two plants can be left in each planting hole.
2) Picking the core for many times, limiting elongation and growth, promoting growth and thickening, and facilitating grafting in the same year. Generally, when the seedling grows to about 30 cm, it is necessary to remove the nucleus 1 time in time to limit the growth of the seedling and promote its growth, which is beneficial to grafting in the same year.
3) fertilizer and water attack hard to promote strong seedlings. Sufficient base fertilizer should be applied before sowing. Generally, 667m2 (mu) should be applied with more than 5000 ㎏ organic fertilizer. When the seedlings grow to about 15 cm, topdressing 50 g of urea at each point, ditching 30 cm around the seedlings, and watering 1 time according to the weather and soil moisture. When the height of the seedlings is 30 cm, topdressing urea100g at each point, and watering properly. After the grafting survived, in mid-August, each hole was applied with organic fertilizer of about 12 ㎏, calcium superphosphate of 0.5 ㎏, 1 ㎏ plant ash and urea of 50 g. In the second spring flowering period, the plants were applied with about 7.5 ㎏ organic fertilizer, 50 g urea and 1㎏ oil residue, and were given water according to soil moisture. From May to June, the supply of water and nitrogen fertilizer should be restricted and squatting seedlings should be implemented.
4) Strengthen summer pruning to promote early flowering and early fruiting. In the year of cutting the anvil, all branches should be left behind, so as to make nutrition and promote the growth of roots. Pull branches in summer to cultivate tree shape; In winter, except the main branch, no other branches will move. In the summer of the following year, the redundant branches below the plastic belt were cut off, and the backbone branches and inner branches were transformed into branches by technical measures such as twisting tips, removing cores and taking branches, which promoted the formation of flower buds and was conducive to early flowering and early fruiting. Future pruning management will be carried out as usual. The young trees of Zaosu pear grow vigorously, with high germination rate and weak branching ability, which are suitable for close planting and take the road of increasing production in groups. Due to the large crown and long life of pear trees, 56 pear trees should be planted every 667 ㎡ (mu), and the row spacing should be 3 mX 4 m.
Zaosu pear is an insect-borne flower with low self-pollination rate and many fruit shapes. Therefore, attention should be paid to the selection of pollinated varieties in cultivation. Apple pear is the main pollination variety in Gansu province, and the ratio of Zaosu pear to Apple pear is 8: 1. Covering cultivation in Shatian can effectively reduce the evaporation loss of soil water, improve the utilization rate of natural precipitation, effectively alleviate the inhibition of water shortage on the growth and fruiting of fruit trees and promote the robust growth of fruit trees. Shatian mulching can also increase the temperature difference, effectively increase the accumulation of sugar in fruit and promote the improvement of fruit quality. The technical points are as follows:
1) coated with cotton sand. Before sand covering, the land should be leveled to make the sand covering uniform. The thickness of sand cover is generally 10 ~ 15 cm. When the thickness is insufficient, the sand cover should be increased every year, and the thickness should be kept at 10 ~ 15 cm. There are tree tray mulching, planting row mulching and whole garden mulching in production, and the whole garden mulching has the best effect.
2) Water winter water, and then apply base fertilizer. Covering Shatian with ordinary natural precipitation can meet the needs of fruit tree growth. However, in late autumn and early winter, when the soil freezes at midnight, 1 water should be poured to make the trees overwinter safely. Pay attention to the base fertilizer when covering Sha Tin. About 90% of the annual fertilization amount should be combined with autumn ploughing or spring ploughing every year. Generally, 6000 ~ 7000 ㎏ organic fertilizer, 30 ~ 40 ㎏ diammonium phosphate and 50 ㎏ potassium sulfate should be applied to 67 ㎏ (mu). The general operation procedure is to sand up first, then spread the fertilizer evenly on the surface, then plough, flatten and cover the sand.
3) Strengthen tree management to make trees full. Covered cultivation in Shatian is beneficial to the formation of flower buds and the fruit trees are strong but not prosperous because the temperature rises rapidly in spring and the spring shoots grow vigorously. In cultivation, the tree should be spindle-shaped. Pay attention to pulling branches during the growing season, erase the buds on the back in time, and carve buds at the missing branches in spring to ensure the fullness of the tree and improve the fruit-bearing ability. Zaosu pear is a big fruit, with an average fruit weight of 200 ~ 250 g. Due to different branches and parts of the fruit, the fruit size is irregular in production, which affects the commercialization. Zaosu pear has strong germination ability, low branching rate and easy to form short fruit branches. The flower buds of Zaosu pear are mainly planted at the top of short and medium branches, with full flower buds at the top, many flowers, high fruit setting rate, good fruit quality and consistent fruit size. In the same inflorescence, the lateral flowers bloom first. Under the same conditions, the flowers that bloom first have good quality, high fruit setting rate and large fruit. Therefore, attention should be paid to thinning flowers and fruits in production. When thinning flowers, we should pay attention to the short branches of the top flower buds, and the marginal flowers are the main ones in an inflorescence, and the fruit spacing is 20 ~ 25 cm. Under the premise that short and medium fruit branches can ensure the yield, try to leave as few or no axillary buds as possible.
Zaosu pear has persistent sepals, so attention should be paid to artificial calyx removal in production. Generally, it is more appropriate to remove calyx after flowering 10 d (day), too late will damage the pulp.
Bagging can keep the fruit surface smooth, reduce the pollution of the fruit surface, help to produce high-grade fruit and improve the commercialization of Zaosu pear, which has been widely used in Gansu production. Gansu Zaosu pear is best bagged in late May. If bagging is too early, the fruit will become smaller, and it should be done about 30 d (day) after flowering. Mancozeb and chlorpyrifos 1 time should be carefully sprayed before bagging, and bagging should be completed within 7 days after spraying. When picking fruits, take the bags with you. When packaging, remove the bags to keep the surface of the fruits clean and prevent water loss. The harvest of pear fruit mainly depends on the variety, the characteristics of the variety, the maturity and use of the fruit and the climate. The fruit is harvested too early, the fruit is immature, the yield is low, the quality is poor, and it is not resistant to storage; If it is harvested too late, the pulp of some varieties of western pears is soft or fluffy, which is not resistant to storage and transportation. Crispy pear is a yellow variety, which is yellow or yellowish brown on the copper-green or green-brown background of fruit surface. When the fruit stalk is easily separated from the fruit surface, it is the suitable harvest time. If it is thick yellow or translucent yellow, it is overripe. The suitable harvest period of Pucheng crisp pear is in the middle and late September.
When determining the harvest time, we must also consider the specific use of the fruit. Fresh fruits for local consumption can be harvested near full maturity. In foreign transportation, distance and transportation conditions should be considered, and the long-distance harvest should be earlier than the short-distance harvest. Good transportation conditions and the use of refrigerated trucks can be harvested later than ordinary transportation conditions. Long-term storage requires harvesting at moderate maturity. If strong winds of 6-7 or above are predicted near the harvest time, ripe, easy-to-fall and windward fruits should be harvested to reduce losses. Crispy pear has large water content and thin skin. When picking, special attention should be paid to handling with care to avoid bumping, stabbing and scratching the fruit. Also prevent picking and breaking fruit branches. The order of picking fruits should be from bottom to top, from outside to inside, so as not to hurt the fruits. When picking fruit, hold the bottom of the fruit with your hands, press your thumb and forefinger on the fruit handle, and lift it up, and the fruit handle will be separated from the fruit branches. When picking double fruits, one hand holds all the fruits, and the other hand picks one fruit first, and then another fruit to prevent the fruit from falling. Pay attention to protect the fruit handle.
The picked fruits should be handled with care, and baskets, baskets and cages should not contain too much fruit. The bottom and periphery of fruit picking baskets, fruit picking cages and fruit baskets should be covered with small bags or sacks, wrapping paper, etc. Not suitable for harvesting in rainy days, foggy days and wet open air. When picking fruits in rainy days, put them in a well-ventilated place and dry them as soon as possible. In addition, be careful not to expose the harvested fruit. Generally, soil holes are used for storage, and mechanical refrigeration storage can be used if conditions permit. The suitable storage temperature of crisp pear is-1 ~ 3℃ and the relative humidity is 90 ~ 95%. Pears can't be put in the same warehouse with other fruits because of the large amount of ethylene released, so as not to affect the storage effect.
1. Carton stacking and storage. Open the selected and graded fruit pads into cartons, each box is 10 kg of fruit; You can also wrap each fruit in glossy paper and box it. If it is a bagged pear, you can put it directly in the box. When stacking cartons, ventilation channels and working channels should be left to make the temperature and gas concentration inside and outside the stack close. This method is simple, effective and widely used.
Plastic bags are stored in small packages. When the storage capacity is small, we can use polyethylene film bags with a thickness of 0.04 ~ 0.06 mm to directly pack the fruits into bags, each bag is 15 kg. After filling, they will not be juxtaposed, but will overlap each other, leaving a certain gap and discharging vertically.
3. Modified atmosphere storage. Crispy pears used for controlled atmosphere storage should be picked early and stored in cold storage with gradually decreasing temperature. The gas component oxygen should be kept at 12% ~ 13%, and carbon dioxide should be lower than 1%.
4. Packaging and storage of microporous membrane. Microporous film is a new type of fresh-keeping film for fruits and vegetables. Its O2/CO2 ratio is greater than that of ordinary plastic bags. It can release high-concentration CO2 gas accumulated during storage of pear fruits, prevent physiological diseases of the fruits, and has multiple functions of regulating qi and keeping moisture. When in use, it can be lined with paper boxes or plastic boxes, and then bundled and packaged.
What are the main problems and preventive measures in storage?
1. Dry consumption of pears and warehouse humidity. Pear fruit has high water content, and water loss during storage is one of the main problems. In order to reduce water loss, it is necessary to increase the humidity of the storage room. Sprinkle water on the ground or hang wet grass curtains around the warehouse wall and ventilation pipes. When cartons are stacked and stored, plastic sheets can also be covered at the stacking place to reduce water loss in ventilation.
2. Carbon dioxide accumulation and ventilation. Pear is extremely sensitive to carbon dioxide, and when it is higher than 2%, it will cause diseases such as core and pulp browning. Therefore, strengthening ventilation and reducing the accumulation of harmful gases such as carbon dioxide and ethylene are also the technical keys to the storage and preservation of crisp pears. During storage, ventilation should be increased in the early and late stages, that is, ventilation 1 ~ 2 hours a day in the early and late stages, and ventilation every two days in the middle stage, with ventilation 1 ~ 2 hours each time. Dry lime can also be put in a breathable bag and put directly into the warehouse to absorb carbon dioxide in the environment. (2) Ventilation and heat insulation vehicle
The insulated car is a kind of car body with only heat insulation function, and there is no refrigeration and heating equipment in the car. During the transportation of goods, the heat exchange between the inside and outside of the car is mainly reduced by the thermal insulation function of the car body with good thermal insulation performance, so as to ensure that the temperature fluctuation of goods during transportation does not exceed the allowable range. This kind of vehicle has the advantages of less investment, less energy consumption and money saving. It is more economical and practical to transport apples with a ventilated and heat-insulated car transformed from an iced refrigerator car, and auxiliary measures such as adding ice in the car can improve the transportation effect.
(2) refrigerated trucks
Railway refrigerated transportation can be transported quickly and with high quality by means of refrigeration, heat preservation, cold prevention, heating and ventilation. The characteristics of refrigerated trucks are: the body is insulated and sealed, and there is a cooling device in the car, which can keep the temperature inside the car lower than the temperature outside the car in warm seasons. In cold season, refrigerated trucks can also be used for transportation without cooling and heat preservation or transportation with heating, so as to keep the temperature inside the car higher than that outside the car.
At present, China's refrigerated trucks include refrigerated trucks with ice, mechanical refrigerated trucks and frozen plate refrigerated trucks.
(3) containers
Container transportation is a developing transportation mode in the world today, which not only saves manpower and time, but also ensures product quality and realizes door-to-door service. This is a great innovation of modern transportation.
On the basis of the container, adding insulation layer and refrigeration and heating equipment can keep the temperature of fresh apples. On the basis of refrigerated container, the airtight layer is added to change the gas composition in the container (reducing O2 concentration and increasing CO2 concentration), which is the refrigerated modified atmosphere container. To control the gas composition, the air in the box can be adjusted by air conditioners in stations and docks, or a liquid nitrogen tank can be installed in the box to release nitrogen instead of the air in the box, so as to achieve the purpose of reducing oxygen. Compared with refrigerated containers, refrigerated modified atmosphere containers can keep the fresh quality of goods.