Techniques of cultivating Sweet Cherry with High quality and High yield

Sweet cherry, also known as big cherry, has been introduced into Yantai by sea from North Korea and Xinjiang by land from Russia from 1880 to 1890. It has been cultivated for more than 100 years. Sweet cherry is mainly distributed in Yantai, Qingdao, Weihai, Taian and Linyi in Shandong, with more varieties such as Na Weng, Da Zi, red cherry and late yellow.

I. Development Prospect and Regional requirements of Sweet Cherry

Sweet cherry compared with Chinese cherry:

① has big fruit, bright color and good taste. Chinese cherry generally weighs 1g to 2g, sweet cherry 5g to 8g, and has strong gloss. Sweet cherry has purple, red and yellow colors, and its soluble solids content, dry matter and sugar content are higher than those of Chinese cherry.

② is resistant to storage and transportation. After 24 hours of storage at room temperature, Chinese cherries can only be browned and then moldy. They can only be sold as soon as they are picked, rotten at the slightest pressure, broken at the slightest shock, and extremely difficult to ship. Sweet cherries are stored at room temperature for 15 days, without discoloration, collapse, mildew, thick and tough skin, light shock without breaking, slightly accumulated and not rotten, so as to facilitate long-distance sales.

③ Chinese cherry fruit is small, difficult to pick, concentrated in ripening period and difficult to organize labor. At the same time, the clump tree shape brings a lot of disadvantages to spraying and fruit picking; sweet cherry fruit is large, tree-shaped and multi-trunk layered, easy to manage flowers and fruits, and the mature fruit is not easy to fall off, which can prolong the market supply cycle.

④ sweet cherry blossoms about 15 days later than Chinese cherry and is not vulnerable to late frost.

Sweet cherries are compared with bulk fruits in the north.

① has early maturity, early listing and significant market value.

② has the advantages of short management time, small investment and high benefit in flowering and fruiting period.

③ fruit ripens before the peak of diseases and insect pests, and few drugs are used in the fruit period, so it is recognized as a safe and non-residual fruit. The market price is 20-40 yuan / kg, and the benefit is obviously higher than that of bulk fruits in the north.

The suitable growth conditions of sweet cherry are as follows: the average annual temperature is 10: 15 ℃, the low temperature period of 7.2 ℃ is more than 1440 hours, the annual sunshine hours are more than 2000 hours, the frost-free period is more than 200 days, and the precipitation is more than 600mm. Sweet cherries can be planted in the coastal areas of the Bohai Sea, the Yellow Sea and the East China Sea, and in the plains, valleys, depressions and gullies of the Yellow River and Yangtze River basins.

Second, high-yield and high-quality cultivation techniques of sweet cherry

1. Cultivated in sandy loam or loam with deep, loose and well-ventilated soil, and on poorly drained and clayey soil, it is easy to cause weak trees and shallow roots. Sweet cherries like light, and the establishment of cherry orchards must be on sunny or semi-sunny slopes with good light conditions. Windbreaks should also be built in areas with strong winds.

2. The variety configuration should be proper, and the sweet cherry can have high and stable yield only if it is matched with good varieties and rootstocks. The rootstock chooses big-leaf Chinese cherry and grinding handle acid to strengthen the root system and improve the wind resistance. The proportion of pollination trees should be 20%-30%, and can be mixed with main varieties in mountainous areas, with 1 pollinated variety for every 3 main varieties and 1 row of pollinated varieties for every 3-4 rows of main varieties in plain areas.

3. The row spacing is 45.5 m × 5 m or 6 m or 7 m, with 218 plants per 667 m. The density of fertile soil is lower and that of barren soil is higher.

4. It is necessary to dig holes or trenches at the predetermined distance between plants, and apply sufficient base fertilizer. Because of the cold, dry and windy winter in North China, autumn seedlings are easy to lose water and dry, so it should be carried out as soon as possible after soil thawing in spring, usually in early March. Hole planting standard: dig a large hole with a depth of 60 cm and a diameter of 100 cm. If you open a trench, dig a ditch of 100 cm in depth and 100 cm in width. Pay attention to placing the topsoil and subsoil separately, and then backfill 20-30cm thick organic matter mixed with topsoil in the planting hole or ditch, such as leaves, straw, weeds or barnyard manure, etc., with feet, and then fill part of the topsoil to about 30 cm from the ground, let the middle slightly higher than around, put the seedlings into the hole (ditch), so that the root system stretch, with filling with shaking seedlings, and with feet, so that the root and soil close. In order to prevent the soil from sinking or being blown down by the wind after watering, it can be fixed with a wooden stick or bamboo pole after planting, and then watered. After water infiltration, a small mound of soil is cultivated at the base of the trunk of the seedling, or covered with 1.2 meters of plastic film, which can play the role of cold and drought resistance and improve the survival rate of seedlings.

5. Sweet cherries have strict requirements for fertilizer and water. When ploughing the orchard in spring, the whole orchard was sprinkled with soil manure and ditched with human manure as basic fertilizer, and chemical fertilizer was applied after fruit harvest from June to July. Sweet cherry should not be fertilized from flowering to fruit harvesting, otherwise it will make the fruit ripening inconsistent and reduce the economic value. It should be noted that the concentrated application of fertilizer in early spring and after fruit harvest, spraying 0.5% urea and 0.5% borax outside the root at the early flowering stage can increase the fruit setting rate by 8% to 14.6%. Sweet cherry is also very strict on water requirements and sensitive to drought and waterlogging. Sweet cherry is an European strain, which requires an ecological environment with abundant rainfall and moist air. Because of its rapid growth, large leaves and high transpiration coefficient, it is necessary to maintain an adequate water supply from flowering to harvest. After blooming in spring, water should be watered for 3 times. The first time after falling flower, the fruit sorghum grain size, the second time when the fruit soybean grain size, during this period the fruit cell division is exuberant, timely watering can promote the fruit vertical diameter growth. The third watering is carried out when the fruit begins to color. At this time, the growth of fruit transverse diameter was accelerated during the period of fruit cell expansion. Satisfying water supply is beneficial to improve yield and quality. Every time you water it, it must be well watered. If the weather is dry and insufficient watering will cause serious fruit drop, resulting in a reduction in yield, if the spring drought is underwatered, the fruit is easy to crack in the later stage of rain, which reduces the economic value of the fruit. Therefore, in the case of drought, we must ensure that "enough water" can be irrigated in order to achieve a bumper harvest.

6. Sweet cherry shaping and pruning. Sweet cherry has strong dryness, rapid growth, strong sprouting power and tall crown, generally more than 4-6 meters. During the period of young trees, the branches grow vigorously and the branch-forming ability is strong. After entering the fruiting stage, the branch-forming ability is gradually weakened, but the demand for light is high. According to these biological characteristics, multi-trunk natural happy shape should be used for shaping and pruning. The method is as follows: after 2-4 scions are split at the base, and before sprouting in late March of the second year, 3-5 similar branches are selected as the trunk of each grafted seedling, and cut and cut at 50 cm above ground. In the future, the annual pruning of the multi-trunk as a multi-trunk extends outward at an angle of 35 degrees, and there is no obvious central leading trunk in the inner chamber, and each trunk leaves two 50-60 cm-long branches each year as extended branches. as the strong dry branches are easy to stand upright, the extended branches should open at an angle of 50 degrees, and the lateral branches extend outward at an angle of 50 degrees, with a length of about 40-50 cm, for the branches below the main branches, lateral branches and extended branches. It is necessary to release the weak branches slowly, cut short the mediocre branches and remove the strong and strong branches. When the young trees grow rapidly, the early maturity of sweet cherry buds can be used to pick the heart for many times to speed up the branches and expand the crown, which is beneficial to early fruiting. Sweet cherry has a natural happy shape with multiple trunks, which can not only form a tree shape 2 or 3 years earlier than that of a single trunk, but also has a large crown and early fruit. Generally, it begins to bear fruit in 4 ~ 5 years, and it can enter the initial full fruit period in 8 ~ 10 years. At the same time, multi-trunk plastic surgery can also prevent the lodging of big trees.

After the sweet cherry enters the fruiting period, it does not need to be pruned. After harvest in June, attention should be paid to removing the dense branches of the inner chamber in order to improve the light conditions of the inner chamber. Removing the new shoots of the same year in the periphery can promote the formation of flower buds and prevent the fruit parts from moving outward, and cut off the dry branches before sprouting in spring.

7. Sweet cherry diseases and insect pests and their control methods. The main diseases of sweet cherry leaves are peach bacterial perforation and round spot, which are serious in the rainy months of July, August and September, which damage branches, leaves, shoots and fruits. If they are not controlled in time, the leaves of the whole tree will fall. It has extremely adverse effects on flower bud formation, tree potential development and flowering and fruit setting in the second year. Therefore, we should pay attention to timely spraying control, spraying 5-degree stone-sulfur mixture before germination in spring to eradicate the spores of overwintering pathogen and control shellfish. 200 times Bordeaux solution was sprayed on the leaves to control the above diseases after harvest in late June and late July.

Sweet cherry branch and trunk glue is a physiological disease. After trunk injury and stimulation, the sap flows out, the branches of the big trees in the full fruit stage flow gum seriously from July to August after harvest, and the red-necked longicorn beetles shed more gum when the damage is serious, because the branches are frozen too early, and when the glue flow is serious, it does great harm to the tree body, so it must be prevented and treated in time according to the cause of the disease. Avoiding injury and irritation of branches is the only way to prevent sweet cherry trees from gumming.

The main pest of sweet cherry is red-necked longicorn beetle. The larvae overwintered in the branches, and the peak period of adult Eclosion was from late June to mid-July, laying eggs in the cracks in the bark of the trunk, and the larvae ate from top to bottom in the xylem of the trunk and big branches. This pest is seriously harmful and difficult to control. It causes glue flow after the trunk is eaten, which seriously weakens the tree potential and can lead to the death of the whole tree.

The prevention and control methods are as follows:

The adults were caught artificially during the emergence period of ① from June to July.

② applied trichlorfon yellow mud on tree trunks and branches in early June to prevent spawning.

③ injected 200x dichlorvos into the wormhole to kill the larvae in the branches.

When insect feces are found in the branches of ④, the newly hatched larvae damaged under the skin should be dug up in time.

⑤ adults have chemotaxis, which can be combined with the control of pear heart borer with sugar and vinegar solution.