Ping CHEN, Jianming LI, Zhenghua JI, Tao LI, Fei ZHAO*

1. Shiyan Science and Technology School, Danjiangkou 442701, China; 2. Hubei Fangling Red Family Farm Co., Ltd., Fang County 442199, China; 3. Shiyan Agricultural Ecological Environmental Protection Station, Shiyan 442099, China

Abstract An excellent individual plant was found from the seedling trees of Chinese cherry (Prunus pseudocerasus), and was grafted onto Hanjiang cherry in 2008, and the new growth was observed to be an excellent line. The clone was established in 2009 and tentatively named as Baliwang. In regional experiment, Baliwang showed the characteristics of large fruit size, bright red fruit color, sweet flavor and long natural fresh-keeping period. It has good commercial properties, high quality, strong resistance to stress and high and stable yield, with great promotion value.

Key words Baliwang, Chinese cherry, Prunus pseudocerasus, New breed

1 Introduction

Cherries (Prunuspseudocerasus) have a beautiful tree shape, beautiful flowers, nutritious fruits and delicious taste, and taste sweet and sour. They are rich in various minerals, sugars, proteins, organic acids, vitamins and other nutrients, and the iron content is especially high, making them popular among consumers. Planting cherries is the preferred project for developing leisure agriculture and building beautiful countryside. Shiyan City, Hubei Province has a large area of cherry planting. According to statistics at the end of 2019, the planting area of cherries in the whole city was 13 900 ha, with an output of nearly 107 000 t, but the proportion of fresh sales was less than 40%, leading to big losses. The main reason lies in the shortcomings of the cherries themselves. The cherry skin is thin and the stalk is easy to fall off. Although cherries are the "first fruit in early spring", they have a short fresh-keeping period, are not suitable for long-distance transportation, and are difficult to sell in different places, which greatly restrict the development of the cherry industry. European sweet cherry (Prunusavium) has thick skin, and its stalk is not easy to fall off, enabling it durable in storage. Although it has been introduced in Shiyan City, Hubei Province, due to its high requirements on climatic conditions, the cultivation response is quite different, and the adaptability is not as good as that of Chinese cherry.

Breeding large-fruited, high-quality and storage-resistant Chinese cherry varieties suitable for regional climate characteristics to fundamentally solve the problem of short sales period in the cherry market is of great practical significance to promote the sustainable development of the cherry industry[1].

2 Breeding process

In 2008, Li Jianming, a villager in Bali Village, Chengguan Town, Fang County, Shiyan City, Hubei Province, found a seed tree in front of his house with red fruits, large fruit size, and a significantly longer fresh-keeping period than the local traditional cherry. In the same year, the branches were plucked and grafted onto Hanjiang cherry, and the next year, fruits were harvested, and they were found to still maintain the characteristics of variation. The morphological characteristics and main economic characters of the fruiting plant were observed and recorded in detail every year, and continuous investigations have found that this strain has large fruit size, good yield, sweet and refreshing taste, and long preservation time. Ultimately, it was selected as an excellent new strain and named Baliwang.

In the fall of 2009, grafting was conducted with Daqingye (large-leaf grass cherry) as rootstock to raise seedlings. The new strain has been planted in Fang County (Chengguan Town), Xiangyang City, Huanggang City and other places successively. Since 2012, the plants start to bear fruits successively in various places, and all of them have performed well and stable. In the distribution area of Chinese cherry, it grows and bears fruit normally, maintains early fruiting, high yield, storability and other characters well, and has a beautiful tree shape and beautiful flowers and fruits, so it is widely praised by the trial area. By 2019, a total of 150 000 plants had been planted, and the planting area reached 267.2 ha, driving the development to a total area of 960 ha, covering Zhangwan, Yunyang, Danjiangkou, Yunxi, Zhuxi, and Fang County in Shiyan City, and radiating Xiangyang, Wuhan, Huanggang and other places.

The basic conditions of the test sites, the phenological period, the yield, and the quality of the fruits are shown in Table 1-4, respectively. With the decrease in latitude, the phenological period gradually shortened. The phenological period in Xiangyang and Huanggang was 3 and 5 d ahead of that in Fang County, respectively. The results of the trials show that after the line was planted, the yield increased steadily, and it entered the full bearing period in the fourth year, and in the sixth year, the output reached 18 000 kg/ha. In production, in order to improve the commodity of the fruits, it is advisable to control the output at 15 000 kg/ha.

Baliwang better maintains the characters of large fruit size, high quality and long shelf life. For the test of shelf life, the fruits were picked when they were ripe with stalks, and naturally spread out indoors (15-25 ℃, 56%-80%) without any treatment, and the quality of the fruits was inspected every day (Table 4).

Table 1 Basic information of regional trial sites

Table 2 Phenological period of Baliwang cherry in the trial sites

Table 3 Yield of Baliwang cherry in the trial tests

Table 4 Fruit quality of Baliwang cherry

3 Main agronomic traits

Through years of trials on excellent individual plants and clones, it is found that the line is a kind of deciduous tree with strong vigor, generally reaching 4-5 m in height. Small trees generally have a central trunk, while the central trunk of large trees is inconspicuous, forming a round crown or oblate crown. Twigs are green and ribbed. The outer bark of twigs is smooth, and gray with lenticels. The leaves are ovate, serrated, rounded at the base and pointed at the apex. The flowers are raceme, with 1-10 flowers, and mostly with 2-5 flowers. The flowers are pink when they do not bloom and turn white when they bloom. Blooming is ahead of leaf spreading. Each flower has 5 petals, with 20-40 stamens and one pistil. The amount of pollen is large, with strong self-pollination capability. The petioles are 0.8-1.5 cm long, with short hairs and 2 glands near the top. The fruits are large, and the average fruit weight is 4 g, with maximum of 6 g. The fruits are red in color, slightly thick in peel, and firm in carpopodiums which are not easy to fall off. The nuclei are small, and the edible part of fruit exceeds 92%. Soluble solids content of fruits ranges from 16.5% to 24.0%. Fruits taste sweet and refreshing. After storing indoors under natural conditions for 5 d, the good fruit rate is still over 95.4%. In normal year, it blooms at the end of February to March, for 10 d. The leaves begin to unfold 5 d after flowering. The fruits ripen from the end of April to the beginning of May. The leaves fall off in December. It is propagated by grafting with Daqingye as the rootstock. The line has the characters of early fruiting and high yield, begins to bear fruit in the 3rdyear, and enters the full bearing period in the 4thyear. The yield per plant is 15-25 kg, and the yield is 18 000 kg/ha in average.

Compared with the control variety, this line has early fruiting and high yield, and the yield per plant increases by 30%. The flavor of the line is sweet and refreshing. The ripening period is 5-7 d later, staggering from the ripening period of local cherries. Under natural conditions, it can be kept for more than 5 d. In terms of storability, shelf life and commodity properties, the line is obviously netter than the control variety. At the same time, other varieties such as Wupi (Sichuan), Wanshouhong (Henan) and Hongfei (Sichuan) introduced to the local area were investigated, and it was observed that the line also has obvious advantages in storage tolerance and resistance to early leaf cast disease.

3.1 Fruit economic traitsThe main economic characters of Baliwang and Hanjiang cherries were determined, and the results are shown in Table 5. The fresh-keeping performance of the fruits in natural conditions was measured, and the good fruit rates of Baliwang, Hanjiang cherry, Wupi, Wanshouhong and Hongfei after stored indoors for 5 d were 95.4%, 35.4%, 86.2%, 24.6% and 35.4%, respectively. The measurement conditions were as follows: picking fruit with carpopodium, placing indoors at room temperature of 15-25 ℃ and relative humidity of 56%-80%, and spreading out naturally.

The results show that various indices of Baliwang cherry were obviously better than the control. Among them, the soluble solids content was 39.3% higher than that of the control, the average fruit weight was 1.8 times that of the control, and the good fruit rate was 2.69 times that of the control, also better than the other varieties. The sugar-acid ratio was 49∶1, and the taste was more preferable.

Table 5 Comparison of fruit quality between Baliwang and Hanjiang cherry

3.2 Botanical charactersYoung shoots are green and ribbed. The outer bark of the branches is smooth, and gray with lenticels, and the lenticels are large and sparse.

The leaves are ovate, rounded at the base, pointed at the apex, and the margin is sharply serrated. The petioles are 0.8-1.5 cm long, with short hairs and 2 glands near the top.

The flowers are raceme, with 1-10 flowers, and mostly with 2-5 flowers. The flowers are pink when they do not bloom and then turn white after blooming. Blooming is ahead of leaf spreading. Each flower has 5 petals, 20-40 stamens, and one pistil, with large amount of pollen and strong self-pollination capability.

The fruits are round, and large (average single fruit weight of 4 g), with red, bright and slightly thick peel, small nucleus, slightly shorter carpopodium, and they are firm and not easy to fall off.

3.3 Phenological periodIn general, flowers start to bloom on March 5, leaves start to spread on March 10, fruits ripen in early May, and leaves fall in November. The phenological period of the varieties is shown in Table 6.

Table 6 Phenological period of Baliwang cherry and the control variety

3.4 Growth and fruiting habitsThe tree has vigorous growth, and the branches are dense, with strong branching ability, generally as high as 4-5 m. In general, small trees have a central trunk, while the central trunk of large trees is inconspicuous, forming a round or oblate crown. The specifications of the crown of a four-year-old tree are 3.5 m × 3.5 m. The fruiting is early, and generally the grafted seedlings can bloom and bear fruit in the 2ndyear. All the long, moderate and short branches can bear fruit, and moderate and short branches are the dominant. After entering the full bearing period, the proportion of bouquet-like fruiting branches increases. The length is less than 5 cm, the internodes are short, and several buds are densely clustered. Except that the terminal bud is leaf bud, the remaining lateral buds are flower buds. The flower buds are of good quality and the fruit setting rate is high. Normal flowers account for 70%. The self-pollination ability is high, and the fruit setting rate is as high as 75% (Table 7-8).

The control variety Hanjiang cherry mainly bears fruit with moderate and short fruiting branches. The short and moderate fruiting branches account for 85%. The main fruiting parts are the 3rd-7thnodes. Fruiting branches are bouquet-shaped. Each fruiting branch bear 1-5 fruits, up to 5 fruits. The 1st-17thnodes of the fruiting branches of Baliwang can all bloom and bear fruit, and the 4th-15thnodes are the dominant, accounting for 70.58% of the total nodes. The branches are bouquet-like, with 4-5 fruits per branch, up to 9 fruits. The fruiting ability of Baliwang was more than 1.5 times that of the control.

Table 7 Growth habits of Baliwang

Table 8 Fruiting branch types of Baliwang

3.5 YieldUnder the experimental management level, the yield per unit area of Baliwang increased significantly compared with the control. After the Baliwang cherry grafted seedlings were planted, the average fruit yield per plant in the third year was 5 kg. In the fourth year, it entered the full bearing period, and the average fruit yield per plant was 15-25 kg. If the plant number is assigned as 630 plants/ha, it can produce 9 450-15 750 kg of fruit. After years of regional tests, it has been proved that this variety has the advantages of storage tolerance, high quality, early and high yield (Table 9). In the production process, in order to stabilize the tree vigor and ensure the quality, the fruits should be thinned appropriately to control the yield per hectare around 18 000 kg.

Table 9 Yield of Baliwang after planting (2013-2019)

3.6 AdaptabilityIn terms of adaptability, the performance of each pilot was stable and consistent, with good growth and fruiting. No drought damage or freezing damage occurred. The variety is resistant to cold, frost, early leaf cast and root knot disease. No serious pests and diseases were found. Only a very small number of fruits cracked during prolonged drought and continuous rain. In short, Baliwang cherry showed good adaptability in the trial areas.

3.7 StorabilityIn terms of storability, the peel of Baliwang cherry is slightly thicker and the carpopodium is firm and not easy to fall off. Under natural conditions, the fresh-keeping period can reach more than 5 d; at low temperature of 4-5 ℃, the fruits can be kept fresh for more than 10 d; and of the temperature is controlled within 0-5 ℃ and the relative air humidity is controlled within 85%-90% with an air-conditioned refrigerator, the shelf life can be prolonged to about 100 d.

4 Main advantages and cultivation precautions

4.1 Main advantages(i) The ripening period is moderate, staggering from the ripening period of the local Hanjiang cherry. Hanjiang cherry ripens in mid to late April, while Baliwang cherry generally ripens in early May.

(ii) The fruits have excellent economic characters. The fruits of this variety are rounded, large and neat. The average single fruit weight is 4 g, and the maximum is 6 g. When ripe, the fruits are full red, and the peel is smooth, bright and beautiful. The edible rate is over 92%. The soluble solids content is 22.1%-24.0%, and the acid content is 6.24 g/L. The juice is rich. The sugar-acid ratio is 49∶1, making the taste sweet and refreshing.

(iii) Early fruiting and high yield. Generally, annual grafted seedlings will bear fruit the following year. The average yield is 5 kg/plant in the third year, and reaches 15-25 kg in the fourth year, showing the character of early fruiting and high yield. The yield was increased by 20%-30% compared to the control.

(iv) Outstanding storability. The fresh-keeping period of Baliwang cherry under natural conditions can reach more than 5 d. Under low-temperature refrigeration, the fruits can be kept for more than 10 d, effectively extending the shelf life and solving the drawbacks of Chinese cherry.

(v) Beautiful flowers and fruits. The tree, flowers and fruits are all beautiful, with high ornamental value.

(vi) Strong stress resistance. The variety has strong anti-freezing and anti-root knot ability. No serious pests and diseases occur during the cultivation process, and it is suitable for ecological cultivation.

4.2 Cultivation precautions(i) Controlling the amount of fruits. This variety is easy to flower, and has a high fruit setting rate. In production, attention should be paid to thinning flowers and fruits to achieve reasonable load, thereby improving fruit quality. (ii) Avoiding waterlogging. When planting in low altitude areas, certain irrigation and drainage conditions are required. (iii) During the ripening period, if it rains continuously or the fruit cracks when overripe, attention should be paid to timely harvesting. Rain-shelter cultivation is recommended in areas with a lot of rain during the ripening period. (iv) In dense or shady conditions, Tuberocephalus momonis is prone to outbreak, and in that case, attention should be paid to timely prevention and control.

5 Key points of cultivation technique

5.1 Transplanting managementGrafting is used for propagation, and the seedlings of Daqingye (large-leaf grass cherry) are used as rootstock[2].

A leeward, sunny slope, hill or small basin with irrigation conditions and an altitude below 1 200 m is chosen for establishing orchard. It is required that the thickness of the active soil layer on hillsides and hills is not less than 50 cm or not less than 50 cm after improvement, the groundwater level in small basins is lower than 120 cm, and the soil pH is 6.0-7.5. The annual sunshine hours are required to be more than 1 500-2 000 h, the annual average temperature is about 15 ℃, the annual rainfall is 700-1 200 mm, and the frost-free period is more than 200 d.

It is better to carry out deep ploughing in the newly established cherry orchard, and the depth of deep ploughing should not be less than 0.5 m. Ridge cultivation is recommended in flat land, gentle slopes and terraces. The width of the ridge surface is 1.0-1.5 m, and the height of the ridges is 0.4-0.5 m. In order to ensure the normal growth of the cherry root system, the terraces should be made high outside and low inside.

Baliwang is mainly planted in autumn and winter, from mid-October to early December. It can also be planted in spring, from late February to early and mid-March, and it is better to be planted before germination. In areas with greater wind damage, windbreaks should be constructed on the main windward side. At a distance of 5-6 m from the cherry planting row, windbreaks should be planted or established artificially, with 2-3 rows, at a plant and row spacing of 1.0 m × 1.0-1.5 m, in a diagonal pattern. The tree species chosen are dominated by arbors with deep root system and tall and compact tree shape, such as poplar, willow and fir. Wide rows of dense planting are advocated. The planting density of terraced gardens with sufficient sunlight should be larger, and vice versa. The planting area should be large. In terraced field, the plant and row spacing can be extended to 3-4 m×4 m, with a density of 630-825 plants/ha; in flat land and gentle slopes, the plant and row spacing is recommended to be 4 m×4-5 m, with 495-630 plants/ha; and in small area planting, the plant and row spacing is recommended to be 3 m×4 m, with 840 plants/ha.

5.2 Reasonable intercroppingIn the sapling stage, in order to improve land utilization and reduce production costs, intercropping legumes or watermelons can be done between rows. Green manure can be planted during the fruiting period, dominated by clover and vetch, and hairy vetch also works well. Clover can be sown in autumn or spring, and it is better to sow in early autumn. Proper early sowing of vetch can improve fresh grass and seed yield, but can’t be too early. Autumn sowing should be done when the average daily temperature drops below 25 ℃, and spring sowing is better when the daily average temperature rises to above 5 ℃. They can be planted with green manure, and mowed in early summer and autumn, and the grass mowed can be mulched around the tree discs. In adult orchard, deep ploughing, hole expansion and hilling can be performed combined with the application of base fertilizer to improve the soil environment, which should be carried out early in autumn and winter to promote root growth.

5.3 Fertilization(i) Base fertilizer. Base fertilizer is applied once a year from mid to late September to before leaf fall. The type of base fertilizer is dominated by organic fertilizer. Considering fertilization rate, 10-20 kg/plant of commercial organic fertilizer is applied for young and early fruiting trees; for big trees at the full bearing period, 30-40 kg/plant (or 15 000-30 000 kg/ha) of organic fertilizer is applied. Annular furrow application is adopted for saplings and trees at the early fruiting stage. The width of the furrows is 30-40 cm, and their depth is about 40 cm. The furrows expand outward year by year. Radial furrow application or hole application is adopted for big fruiting trees. The application depth is recommended to be about 30 cm for young trees and trees in the early fruiting stage, and about 50 cm for trees in the full bearing stage.

(ii) Topdressing. In the early full blooming stage, 0.3% borax and 0.2%-0.4% potassium dihydrogen phosphate are applied outside the roots to promote fertilization and increase fruit setting rate. After the flowers fade, the young fruits begin to develop, and the cores swell, so fertilizer should be applied in time in 4 times. Before flowering, nitrogen and phosphorus fertilizers are used to supplement tree nutrition in time and promote flower bud germination and spring shoot growth; fruit enlargement fertilizers are mainly nitrogen and potassium fertilizers, supplemented by phosphorus fertilizer, to promote fruit expansion, reduce physiological fruit drop, improve fruit quality, and supplement tree nutrition at the same time; before fruit coloring, quick-acting potassium fertilizer is applied, 20-25 d before harvesting; and after fruit picking, quick-acting fertilizer is applied, and compound fertilizer is recommended. For primary fruiting trees, 0.3-0.5 kg of urea and 0.3 kg of potassium dihydrogen phosphate are applied to each plant. For the trees in the full bearing period, 0.6-1.0 kg of urea and 0.6 kg of potassium dihydrogen phosphate, or 1-2 kg of compound fertilizer can be applied to each plant. The primary fruiting trees are mainly fertilized in annular furrows, and for the trees at the full bearing stage, fertilizers are applied in annular furrows or radial furrows, which are about 30 cm deep. For primary fruiting trees, the fertilization depth is slightly small. For foliar fertilization, 0.3% urea and 0.2%-0.4% potassium dihydrogen phosphate is sprayed. The spraying time is generally in the afternoon and evening. Since there is dew in the morning and the temperature is high at noon, spraying is forbidden in that time. When topdressing is conducted outside the roots during flowering, 0.1%-0.2% borax can be added.

5.4 Moisture managementBaliwang cherry should be watered before flowering, during the hard-core stage of the fruit, during the fruit picking stage, and during the flower bud differentiation stage in case of drought. Soil moisture should be maintained at 70%-80% of the maximum water holding capacity in the field. Water should be irrigated when it is below 65%, and drained when it is above 90%. When the leaves are not damp in the early morning, water should be irrigated. When the temperature in summer continues to be above 35 ℃, and the leaves begin to wilt, water should be irrigated immediately. In case of summer drought and autumn drought, it should be irrigated in the early morning or evening.

According to local conditions, furrow irrigation, drip irrigation and sprinkler irrigation can be used.

There are drainage ditches in the orchard. The main drainage ditches are 60-70 cm deep, and the branch drainage ditches are 30-40 cm deep. Drainage is carried out in time after rain. In low-lying orchards prone to flooding, the trees can be earthed up to change to high ridge planting.

5.5 Pruning managementNatural heart shape or modified trunk shape is adopted.

5.5.1Natural heart shape. There is no central leading stem. The stems are 50-60 cm high. There are 3-4 main branches in the whole tree, with an opening angle of 30°-40°. Each main branch is left with 3-5 anticlines or lateral branches, which are alternately arranged. The opening angle of lateral branches is 70°-80°. It is advocated to promote branching by pruning in summer. The lateral branches extend uniaxially. The tree height is 3.0-3.5 m. The crown is round or oblate.

After planting, a 50-60-cm-long stem is remained. In the first winter, the first branch at the top is used as the central branch, and 3 branches with strong growth and uniform distribution are selected at every 5-10 cm downward as the main branches. Each of them is left 50-60 cm long, and the cut is outward. The central branch is left about 60-70 cm long to promote branching, so that the main branches can open up. The other braches below the first main branch and the accessory branches in the shaping belt are left 20-30 cm long according to the growth potential.

In the second year, when the new shoots grow to about 20 cm in length in spring, the plant is pinched to increase lateral branches, nourish the tree body, and promote the early fruiting of sapling. When pruning in winter, the lateral branches on each main branch are reasonably arranged. The first lateral branch should be more than 40 cm away from the trunk, preferably on the anticline side. The lateral branches are left 40 cm long, the extended part of each main branch is left longer than 60 cm, and the extended part of the central trunk, as well as the other branches on it, are not pruned.

In the third year, when the main and lateral branches grow to more than 60 cm in summer, pinching is conducted timely to promote the germination of buds. Accessory branches are utilized to cultivate fruiting branches and the extended parts of the backbone branches. In winter pruning, the central branch is left about 50-70 cm and retracted, and the branches above it are transformed into small and medium-sized fruiting branches.

5.5.2Modified trunk shape. The trunk is 40-50 cm long. The central leading branch maintains the advantages of growth, and above it, there are about 10 uniaxially extended branches arranged in layers or spirals. The angle of the main branches is nearly horizontal. The tree is about 3 m high. At the sapling stage, light pruning and summer pruning are the dominant. Using summer pruning measures such as slow release, pinching, pruning and twisting, the amount of peripheral branches is reduced, the angle of the main branches is opened, the growth potential at the top is eased, and the illumination in the crown is improved to expand the crown rapidly. At the same time, the short branches in the middle and lower parts are well protected to promote the formation of flower buds and the cultivation of fruiting shoots. To prevent the main branches from splitting, the branch with a small opening angle should not be chosen as a main branch, and there should not be too many wounds on the trunk.

After the seedlings are planted, the branch is left 50-70 cm long. In the winter pruning of the first year, the first branch at the top is used as an extension branch of the central trunk, and branches with robust growth and reasonable orientation are selected as main branches every 15-20 cm downwards. The first main branch is not less than 40 cm above the ground, and 3-4 main branches cover 360°. Each main branch should be cut short at 40-50 cm, and the cut is outward. The uppermost extension branch of the central trunk is about 10 cm longer than the main branch when pruned, and the remaining branches are left 20-30 cm long according to the growth potential.

In the second year, when the new shoots grow to a length of about 20 cm in spring, the plant is pinched. In winter, within the horizontal angle between the first main branch and the second main branch on the upper part of the extension branch of the central trunk, the fourth or fifth main branch is cultivated, and at a distance of 15-20 cm, the fifth or sixth main branch is selected. In the same manner, main branches are staggered on the extension branch of the central trunk. The extension branch of the central trunk and the main branches are cut short.

In the third year, in summer, when the extension branch of the central trunk grows to more than 60 cm, the plant is pinched in time to promote the germination of accessory branches, which are utilized to cultivate the extension branch of the central trunk and the new main branches on the upper part. In winter, the central branch is cut short at about 50 cm, and the fourth and fifth, or fifth and sixth main branches are also cut short at the same time.

5.6 Flower and fruit management

5.6.1Flower thinning. The weak branches inside the crown, the flower buds on the overly dense branches, and the weak and deformed flowers on perennial bouquet-like fruiting branches can be thinned out before flowering or at the beginning of flowering.

5.6.2Fruit thinning. In early and mid-April, after the physiological fruit drop is over, small and deformed fruits are thinned out.

5.7 Disease and pest controlBaliwang cherry has strong disease resistance, and even if disease occurs, it is mild, so attention should be paid to prevention. In addition, management should be strengthened, and pruning should be reasonable, to enhance tree vigor, and improve disease resistance. In winter, the orchard should be cleaned, and the plants should be protected well. Before germination in autumn, winter and spring, 3°-5° lime sulfur mixture or 500-800 times dilution of 70% thiophanate-methyl can be sprayed for protection. After fruit picking, Bordeaux mixture is sprayed twice for tree protection from May to June.

The main pests that occur in Baliwang cherry areAphiscitricolaVan der Goot,Phaleraflavescens,Grapholithamolesta,DrosophilamelanogasterandMyzuspersicae. Comprehensive prevention and control measures should be adopted.

5.8 Fruit harvestingAfter the background color of the fruit fades from green, it turns from yellow to red, and when the fruit surface is completely red and shiny, it is ripe, usually around May Day. When harvesting, morning with dew and noon with high temperature are avoided. Fruit is harvested with carpopodium to extend shelf life. Damage from Drosophila melanogaster is prevented.

5.9 Packaging and StorageCarton, plastic box or bamboo basket with local characteristics can be used[3].

At room temperature, the fruit can be stored for 5 d; at a low temperature of 4-5 ℃, the fruit can be kept fresh for 10 d; in air-conditioned refrigerator with temperature around 0 ℃ and relative air humidity of 85%-90%, the fruit can be kept fresh for about 100 d.

5.10 Establish quality management system filesThe quality traceability system for cherry ecological planting and production can be established and improved. In the planting process, the name, source, usage, dosage, and start and end date of use, the prevention and control methods and dosages of diseases and pests, the harvest, transport, storage and sales records are well recorded. All records and materials are organized and archived and kept for more than 3 years.

6 Suitable planting range

Baliwang cherry has a wide range of adaptations. It can grow normally and bear fruit in the distribution areas of Chinese cherries, including hillsides, hills and small basins with annual sunshine hours of 1 500-2 000 h, annual average temperature of

about 15 ℃, annual rainfall of 700-1 200 mm, frost-free period more than 200 d, soil pH of 6.0-7.5, groundwater table not exceeding 120 cm and altitude below 1 200 m.