Sweet cherry out-of-season delayed cultivation method suitable for southern regions

Abstract

The invention relates to the technical field of sweet cherry planting in the southern region, in particular to a sweet cherry out-of-season delayed cultivation method suitable for the southern region. The method comprises the steps that a high-temperature-resistant sweet cherry variety is selected, temperature and humidity are regulated and controlled through an anti-season cultivation greenhouse by means of an intelligent environment control system, and the optimal conditions of different growth stages are ensured. The temperature is controlled to be 2-4 DEG C through refrigeration and shading in the dormancy period, the temperature is increased to 10-20 DEG C in the germination period, the appropriate temperature of 12-25 DEG C is maintained in the flowering period, the light supplementing technology and natural light are combined in the young fruit period, and the temperature is controlled to be 18-28 DEG C in the mature period. According to the method, the mature period of the sweet cherries is delayed to July to August, the cultivation efficiency and the fruit quality are improved through remote monitoring and intelligent management, and the anti-season fruit market requirements are met.

Description

Technical Field

[0001] The invention relates to the technical field of sweet cherry planting in southern regions, and in particular to a sweet cherry off-season delayed cultivation method suitable for southern regions. Background Art

[0002] Sweet cherry (Prunus avium L.), also known as big cherry and cherry, belongs to the deciduous fruit tree of the genus Prunus, subgenus Prunus, Rosaceae. Domestic sweet cherries are mainly cultivated in the north, and the maturity period is concentrated in March-June. Domestic sweet cherries sold in the rest of the month are relatively rare. Due to the warm and humid climate in the south, especially the high temperature and heavy rain in summer, sweet cherry has been one of the fastest growing fruit trees in recent years. There are many problems that need to be solved in the cultivation process. The Chinese invention patent application (publication number: CN104885841A, CN104920134A, CN104838935A) and the Chinese invention patent application applied by the applicant (publication number: CN107182683A, publication date: 2017-09-22) disclose a planting method for planting sweet cherries in warm areas in the south, realizing the planting of sweet cherries in the south.

[0003] The cultivation area of ​​sweet cherries has gradually expanded in southern regions such as Zhejiang, and they are mostly produced by sheltering from rain and shading. The fruit maturity period is generally in May, and the fruit maturity period can be advanced to April through early cultivation. As applied for by the applicant, the Chinese invention patent application (publication number: CN114931058A, publication date: 2022-08-23) is a cultivation method for promoting the early maturity of sweet cherries in southern regions by regulating temperature and humidity. Through the facility film covering and heating bud and flower promotion regulation technology, under the condition that the required cold amount meets its own dormancy needs, reasonable temperature regulation is carried out during the budding period and the fruit color change period to promote early germination and early maturity, change its growth and development cycle, and promote the early listing of fruits. The same sweet cherry variety can mature in mid-to-late March, which is 30-40 days earlier than the ordinary rain shelter and shade cultivation, greatly improving the economic benefits.

[0004] At present, the off-season cultivation of sweet cherries mainly promotes early cultivation by "raising temperature to promote early cultivation", and there are few studies on off-season delayed cultivation by "lowering temperature to delay". There are no sweet cherries that mature in July and August in southern regions such as Zhejiang. The off-season delayed cultivation of sweet cherries in southern regions faces many problems, among which the problem of high temperature in summer is particularly prominent, which not only restricts the off-season cultivation of sweet cherries, but also has an adverse effect on rain shelter and shade cultivation. In July 2024, the average temperature in Taizhou, Zhejiang was 29.85℃, the highest temperature was 38.90℃, and the lowest temperature was 25.70℃. The high temperature environment outside seriously restricted the off-season cultivation of sweet cherries. Therefore, "external shading and internal light supplementation" is one of the effective ways to solve the high temperature problem during the fruit ripening period in southern China. With the continuous improvement of sweet cherry cultivation technology, off-season delayed cultivation has gradually come into people's view, and problems such as the regulation of environmental conditions for off-season cultivation of sweet cherries need to be further resolved. Summary of the invention

[0005] In view of the deficiencies in the prior art, the present invention provides a method for off-season delayed cultivation of sweet cherries suitable for southern regions. The method ensures the efficient growth of sweet cherries in an off-season environment and improves the fruit quality to meet market demand through scientific environmental control equipment and supplementary lighting technology.

[0006] In order to achieve the above-mentioned purpose, the present invention adopts the following technical solutions:

[0007] A method for delayed cultivation of sweet cherries in off-season suitable for southern regions, the method comprising the following steps:

[0008] 1) Select sweet cherry varieties that are grown in the southern region and are suitable for growing in the southern region and are resistant to high temperatures;

[0009] 2) Off-season cultivation greenhouses, with light-shielding rubber-plastic insulation cotton covering the outside of the greenhouse, and intelligent artificial environment control units inside the greenhouse to regulate temperature and humidity in the off-season cultivation greenhouse;

[0010] 3) The dormant period is from April to May. The plants are refrigerated and dormant. The temperature in the greenhouse is controlled at 2-4°C and no light is seen.

[0011] 4) During the budding period in May, gradually increase the temperature, turn on the insulation cotton, and control the temperature in the greenhouse at 10-20℃;

[0012] 5) During the flowering period from May to June, simulate the normal temperature in spring and control the temperature in the greenhouse at 12-25℃;

[0013] 6) During the young fruit stage from mid-June to early July, the temperature in the greenhouse was controlled at 15-25℃, and supplementary lights and natural light were used for photosynthesis; the supplementary lights used were Zhongkexicai supplementary lights, with a red-blue light ratio of 1.8, and 1m×0.75m high-density supplementary lights were used for supplementary lighting. The supplementary lights were 20cm to 80cm away from the leaves. During the supplementary period, the temperature of the off-season cultivation greenhouse was controlled in the range of 20℃ to 25℃; the lighting duration was controlled to be 15-18 hours per day, and the supplementary lights were automatically turned on when the natural light was lower than 930Lux;

[0014] 7) During the maturity period from July to August, the temperature in the greenhouse should be controlled at 18-28℃;

[0015] 8) After harvesting in September and October, the refrigerator does not need to be turned on, the insulation cotton is opened, all greenhouse films are opened, normal management is carried out, and fertilizer and water management is strengthened.

[0016] Preferably, the high temperature resistant sweet cherry varieties are "Qi Zao" or "Mei Zao".

[0017] As the preferred choice, "Qizao" is a 5-year-old KGB tree shape, and "Meizao" is a 4-year-old tall and slender spindle tree shape.

[0018] Preferably, during the young fruit stage, the temperature in the "Qi Zao" off-season cultivation greenhouse is regulated at 20°C, and the temperature in the "Mei Zao" off-season cultivation greenhouse is regulated at 25°C.

[0019] Preferably, the off-season cultivation greenhouse is a single arch shed with a length of 40m and a width of 11m, and the outside of the shed is covered with 5cm thick rubber-plastic insulation cotton.

[0020] As a preferred choice, the power of Zhongke Xicai fill light is: 60W, the main wavelength is: 699.0nm, the luminous flux is: 4030.42 1m, and the fill light time is from 6:00 to 22:00 every day.

[0021] Preferably, the installation height of the fill light is 40 cm to 120 cm, and it is arranged in a staggered manner according to the different tree shapes to ensure the uniformity of sweet cherry photosynthesis.

[0022] Preferably, fertilization management includes applying urea, potassium dihydrogen phosphate and trace element fertilizers, supplementing nutrients in stages to ensure the improvement of leaf photosynthetic efficiency and fruit quality.

[0023] As a preferred option, remote monitoring devices are used to monitor the temperature, humidity and light intensity in the greenhouse in real time to ensure that the growth environment of sweet cherries is always in the best condition.

[0024] Preferably, ripe fruits can be obtained from July to August through off-season cultivation methods.

[0025] The present invention adopts the above-mentioned technical solution to provide a method for delayed cultivation of sweet cherries in the off-season suitable for the southern region. Aiming at the hot and humid climate conditions in the south, the invention realizes efficient off-season production of sweet cherries through multi-step temperature, humidity and light control, and delays the fruit maturity period to July to August. The method has the following significant technical effects:

[0026] 1. Efficient environmental control: Through the intelligent artificial environment control system, combined with light-shielding rubber and plastic insulation cotton, the temperature and humidity in the greenhouse are precisely controlled. Especially during the dormant and budding periods, by precisely adjusting the temperature, maintaining a low temperature of 2°C to 4°C and a lightless environment, the sweet cherries are successfully forced to enter the dormant period and effectively break the dormancy. This control avoids the adverse effects of high temperatures in the south on dormancy and budding, and ensures that sweet cherries grow and develop within a suitable temperature range.

[0027] 2. Optimization effect of combining supplementary lighting with natural light: From the young fruit stage to the fruit maturity stage, the use of Zhongkexicai supplementary lighting (red-blue light ratio 1.8) combined with natural light has achieved the optimization of light supplementation in the greenhouse. This supplementary lighting technology supplements 15 to 18 hours of light per day from June to July, ensuring the stable photosynthesis of sweet cherries, increasing the net photosynthetic rate, and significantly promoting the development and quality of the fruit. Through the reasonable arrangement of high-density supplementary lighting (1m×0.75m), the light evenly covers the tree crown, avoiding insufficient or excessive light concentration.

[0028] 3. Improved fruit quality and yield: The present invention maintains a suitable temperature of 20°C to 25°C during the young fruit stage and the mature stage, ensuring that the sweet cherry fruit expands and accumulates sugar at the optimal temperature. Experiments have shown that this method effectively increases the soluble solid content of the fruit, increases the weight of a single fruit, and significantly improves the appearance and taste of the fruit, thereby increasing the commercial value.

[0029] 4. Extending the harvest period and improving market value: Through precise temperature, humidity and light management, the present invention delays the ripening period of sweet cherries to July or August, breaking the traditional seasonal restrictions, extending the supply cycle of sweet cherries, and filling the gap in the market supply of sweet cherries in summer. This delayed cultivation method provides growers in the southern region with broader market prospects and economic benefits.

[0030] 5. Intelligent monitoring and energy-saving effect: Through the remote monitoring system, the temperature, humidity and light intensity are adjusted in real time. The present invention realizes the intelligent management of the sweet cherry cultivation process, reduces manual intervention, and significantly improves the cultivation efficiency. At the same time, during the non-critical growth period, such as September to October, by opening the greenhouse film and insulation cotton, natural cooling and ventilation management, energy consumption is reduced, and energy saving and environmental protection are achieved.

[0031] In summary, the present invention significantly improves the growth efficiency, fruit quality and economic benefits of sweet cherries in off-season delayed cultivation in southern China through a number of innovative temperature, humidity and light control technologies, and has broad application prospects. DETAILED DESCRIPTION

[0032] The following is a clear and complete description of the technical solutions in the embodiments of the present invention in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] Example 1: Off-season delayed cultivation method for sweet cherries in southern China

[0034] 1. Variety selection

[0035] In this embodiment, the sweet cherry varieties "Qizao" and "Meizao" suitable for the high temperature climate conditions in the southern region are selected. "Qizao" is suitable for 5-year-old KGB tree cultivation, while "Meizao" is suitable for 4-year-old tall spindle tree cultivation. These two varieties have strong tolerance to high temperature environments and can meet the needs of off-season cultivation in the southern region.

[0036] 2. Greenhouse structure and environmental control

[0037] The off-season cultivation greenhouse adopts a single arch structure, which is 40 meters long and 11 meters wide. The outside is covered with 5 cm thick rubber-plastic insulation cotton to ensure the stability of temperature control inside the greenhouse. The greenhouse uses an intelligent artificial environment control unit to create an environment suitable for the growth of sweet cherries through precise control of temperature and humidity, especially to ensure the off-season temperature requirements.

[0038] 3. Dormant period management (April-May)

[0039] During the dormant period from April to May, refrigeration equipment is used to control the temperature in the greenhouse at 2°C to 4°C, and the greenhouse is kept in a dark environment to simulate the natural dormant conditions in winter. The low temperature and dark environment effectively break the dormant period of sweet cherries and avoid the adverse effects of high temperature on the dormancy of sweet cherries.

[0040] 4. Management during the budding period (May)

[0041] After entering the budding period in May, gradually increase the temperature in the greenhouse, open the insulation cotton, and control the temperature between 10℃ and 20℃ to simulate the temperature change process in the natural environment, so as to promote the smooth germination of sweet cherries and the beginning of growth and development.

[0042] 5. Flowering period management (May-June)

[0043] During the flowering period from May to June, the temperature in the greenhouse is controlled between 12℃ and 25℃ to simulate the temperature conditions in spring to ensure the normal opening and pollination of flowers. At this time, the temperature of the greenhouse needs to be dynamically controlled to cope with external climate changes and ensure the smooth completion of the flowering period.

[0044] 6. Management during the young fruit stage (mid-June to early July)

[0045] During the young fruit stage from mid-June to early July, the temperature in the greenhouse is controlled at 20℃ to 25℃. The temperature is adjusted according to the different varieties. For example, the temperature of the "Qizao" variety is maintained at 20℃, and the temperature of the "Meizao" variety is maintained at 25℃. At this stage, supplementary lighting is particularly important. Zhongke Xicai supplementary lighting is used, with a red and blue light ratio of 1.8. The installation distance of the lamp is 20cm to 80cm, and it is combined with natural light for photosynthesis. The daily supplementary lighting duration is 15 to 18 hours. When the external light intensity is lower than 930Lux, the supplementary light is automatically turned on to ensure sufficient light to promote the healthy growth of the fruit.

[0046] 7. Management during the maturity period (July-August)

[0047] During the fruit ripening period from July to August, the temperature in the greenhouse is controlled between 18℃ and 28℃ to ensure that the fruit matures at the most suitable temperature. At the same time, light is continuously added to ensure that the fruit accumulates enough sugar during photosynthesis, thus improving the quality and taste of the fruit.

[0048] 8. Post-harvest management (September-October)

[0049] From September to October, after the fruit is harvested, there is no need to turn on the refrigeration equipment. At this time, the insulation cotton is opened, the greenhouse film is completely uncovered, and normal natural management is carried out. During this stage, fertilizer and water management are strengthened to prepare for the cultivation of sweet cherries in the next season.

[0050] 9. Fill light configuration and fertilization management

[0051] The installation height of the supplementary light is reasonably arranged according to the tree shape, ranging from 40cm to 120cm, to ensure that the light evenly covers the entire crown. In terms of fertilization management, urea, potassium dihydrogen phosphate and trace element fertilizers are used to supplement nutrients in stages. Topdressing is carried out before flowering, during the young fruit stage and during the fruit ripening stage to ensure the improvement of leaf photosynthetic efficiency and fruit quality.

[0052] 10. Remote monitoring and automated management

[0053] The temperature, humidity and light intensity in the greenhouse are monitored in real time through remote monitoring instruments. The intelligent system automatically adjusts the temperature, humidity and light intensity in the greenhouse according to environmental data to ensure that the sweet cherry growth environment is always in the best condition. The system also significantly reduces the complexity of manual operations and improves management efficiency.

[0054] Through the above implementation scheme, the off-season delayed cultivation of sweet cherries has achieved remarkable results in the southern region. The experimental results show that by adopting the cultivation method of the present invention, the fruits of sweet cherries can mature smoothly from July to August, and the single fruit weight, soluble solid content and fruit hardness are significantly improved. Especially in the process of temperature and light regulation from the young fruit stage to the mature stage, the fruit quality of sweet cherries is stable, the taste is sweet, and the market competitiveness is significantly enhanced.

[0055] Test example

[0056] In order to verify the effectiveness of the off-season delayed cultivation method of sweet cherries in the southern region of the present invention, the applicant conducted the following experiments.

[0057] 1. Materials and methods

[0058] 1.1 Test materials

[0059] This study was conducted in an off-season greenhouse where temperature and light are controlled by artificial intelligence at Taizhou Academy of Agricultural Sciences. Sweet cherry varieties "Qizao" and "Meizao" were used as test materials. "Qizao" is a 5-year-old KGB tree shape, and "Meizao" is a 4-year-old tall spindle tree shape. The tree vigor and conventional management are consistent. The conventional management method refers to the Chinese invention patent CN201710524755.5. The off-season cultivation greenhouse is a single arch shed with a length of 40m and a width of 11m. The outside of the shed is covered with 5cm thick rubber-plastic insulation cotton. The temperature and humidity are controlled by two 10KW rated power big cherry intelligent artificial environment control units (Zhengjin Environmental Technology Co., Ltd.) in the greenhouse. Three different fill lights, ordinary fill lights, Zhongkexicai fill lights, and full-spectrum plant fill lights, were used for fill light experiments. Among them, the big cherry intelligent artificial environment control unit and fill lights can be automatically operated by setting temperature and light thresholds.

[0060] Ordinary fill light: 60W, white light. Zhongkexicai fill light: 60W, main wavelength: 699.0nm, luminous flux: 4030.421m, red light to blue light ratio (R / B): 1.8. Full spectrum plant fill light: 60W, main wavelength: 699.4nm, luminous flux: 3042.681m, red light to blue light ratio (R / B): 2.5. During the measurement of photosynthesis, the rubber and plastic insulation cotton outside the greenhouse was not turned on, there was no natural light inside the greenhouse, and only the fill light provided artificial light. Fill light treatment time: 1m×1.5m low-density fill light or 1m×0.75m high-density fill light from mid-June to early July. The fill light fill light time is 6:00-22:00. During this period, when the external natural light is lower than 930Lux, the fill light automatically controls to turn on the fill light. The insulation cotton is manually turned on at 7 o'clock and turned off at 17 o'clock. The total effective light duration is 16 hours per day. Pengyun remote monitoring instrument S21A is used to collect air temperature, soil temperature, light intensity, etc. in the greenhouse every 5 minutes.

[0061] 1.2 Test methods

[0062] 1.2.1 Effect of different temperatures on the synthetic efficiency of sweet cherry supplementary lighting

[0063] Four treatments, T1-T4 (the set temperature thresholds are 10℃, 15℃, 20℃, and 25℃, respectively), were set up, and the LI-6400X portable photosynthetic instrument was used to measure the net photosynthetic rate (Pn), stomatal conductance (Cond), intercellular CO2 concentration (Ci), transpiration rate (Tr) and other indicators of "Qizao" and "Meizao" under different temperature treatment conditions. Three plants were randomly selected for each treatment, and three mature leaves in the middle of the new shoots were selected from each plant in different directions for measurement. The photosynthesis of the leaves was measured at a distance of 80cm from the light source (light intensity 2595.93Lux). The supplementary lights were installed at a density of 1m×0.75m. The measurement times of T1-T4 were around 9:20, 11:00, 13:00, and 14:00, respectively. During this period, the greenhouse rubber-plastic insulation cotton was not turned on, and the temperature rose slowly and naturally.

[0064] 1.2.2 Effects of different light quality supplementary lighting on photosynthesis of sweet cherry

[0065] Three treatments, M1-M3 (ordinary fill light, Zhongkexicai fill light, and full-spectrum plant fill light, respectively), were set up. The LI-6400X portable photosynthetic instrument was used to measure the parameters of sweet cherry net photosynthetic rate (Pn), stomatal conductance (Cond), intercellular CO2 concentration (Ci), and transpiration rate (Tr) under variable light intensity conditions. Three plants were randomly selected for each treatment, and three mature leaves in the middle of the new shoots were selected from each plant in different directions for measurement. The photosynthesis of the leaves at a distance of 80 cm from the light source was measured. During the measurement of photosynthesis, the rubber-plastic insulation cotton was not turned on, there was no natural light inside the greenhouse, and only the fill light provided artificial light. The ambient temperature in the greenhouse was 20°C during the measurement. The fill light was installed at a density of 1m×0.75m.

[0066] 1.2.3 Effects of different distances of supplementary lighting on photosynthesis of sweet cherry

[0067] Four treatments were set up, N1-N4 (20cm, 40cm, 80cm, and 120cm from the light source, respectively). The LI-6400X portable photosynthetic instrument was used to measure the parameters of sweet cherry leaves at different distances from the supplementary light at 20℃, including net photosynthetic rate (Pn), stomatal conductance (Cond), intercellular CO2 concentration (Ci), and transpiration rate (Tr). The supplementary light was a Zhongkexicai supplementary light, which was installed at a density of 1m×1.5m. Three plants were randomly selected for each treatment, and three mature leaves in the middle of the new shoots were selected from each plant in different directions for measurement. The results were repeated three times and the average value was taken. During the measurement of photosynthesis, the rubber-plastic insulation cotton was not turned on, there was no natural light inside the greenhouse, and only the supplementary light provided artificial light. The ambient temperature in the greenhouse was 20℃ during the measurement.

[0068] 1.2.4 Effects of different density supplementary lighting on photosynthesis of sweet cherry

[0069] Two treatments, S1 and S2, were set up, with supplementary lights installed at densities of 1m×1.5m and 1m×0.75m, respectively. The LI-6400X portable photosynthetic instrument was used to measure the effects of different densities of supplementary lights on the net photosynthetic rate (Pn), stomatal conductance (Cond), intercellular CO2 concentration (Ci), transpiration rate (Tr) and other parameters of sweet cherry under variable light intensity conditions. The supplementary lights were Zhongke Xicai supplementary lights (60W), and the measurement temperature was 20℃. Three plants were randomly selected for each treatment, and three mature leaves in the middle of the new shoots were selected from each plant in different directions for measurement. The results were repeated three times and the average value was taken. During the measurement of photosynthesis, the rubber-plastic insulation cotton was not turned on, there was no natural light inside the greenhouse, and only the supplementary lights provided artificial light.

[0070] 1.2.5 Effects of different lighting treatments on sweet cherry fruit quality

[0071] Three different treatments were set up: P1-P3 ordinary fill light, Zhongkexicai fill light, and full-spectrum fill light. 30-40 fully mature sweet cherry fruits were randomly picked to measure important indicators such as single fruit weight and soluble solid content. The mass of the fruit was randomly weighed using a 1 / 1000 electronic balance. The hardness of the fruit was measured directly with the peel using a GY-1 hardness meter. The total soluble solids, total acid, and solid-acid ratio were measured using a Japanese Atuo fruit sugar and acid tester. With reference to the "Cherry Germplasm Resource Description Specifications and Data Standards", the flavor and taste of the fruit were evaluated, and the sourness and sweetness of the fruit were intuitively evaluated.

[0072] 1.3 Statistical analysis

[0073] The data were statistically processed using Microsoft Office Excel 2007, and the variance analysis of the results of the one-way randomized block experiment was performed using STST software.

[0074] 2. Results and Analysis

[0075] 2.1 Effect of different temperatures on the synthetic efficiency of sweet cherry supplementary lighting

[0076] As can be seen from Table 1, the air temperature in the greenhouse is not much different from the set temperature threshold of each treatment, that is, the air temperature in the greenhouse can be maintained at the required test temperature during the test. Through the study of the air temperature, leaf temperature, and calculated leaf temperature parameters of the photosynthetic instrument sample room, it was found that under the low temperature treatment of 10°C, the leaf temperatures of "Qizao" and "Meizao" exceeded 15°C; as the temperature increased, the leaf temperatures of "Qizao" and "Meizao" gradually increased, and the leaf temperatures of "Meizao" were slightly higher than "Qizao", and ordinary fill lights and Zhongke Rare Lighting showed the same pattern. In summary, the leaf temperature gradually increased with the increase of the outside temperature and the leaf temperature was always higher than the ambient temperature. When the outside temperature was lower than 15°C, in order to maintain the normal growth of the tree, the leaf temperature would not decrease with the decrease of the ambient temperature.

[0077] Table 1 Effects of different temperature treatments on sweet cherry leaf temperature

[0078]

[0079]

[0080] As can be seen from Table 2, temperature has a great influence on the photosynthesis of sweet cherry. The net photosynthetic rate of "Qizao" reached the maximum value when the temperature was 20℃, and the net photosynthetic rate of "Meizao" reached the maximum value at 25℃. The ordinary supplementary light and Zhongkexicai supplementary light showed the same rule. With the continuous increase of the temperature of T2-T4 leaves, the stomatal conductance and transpiration rate of "Qizao" and "Meizao" showed a trend of gradually increasing. When the temperature was 25℃, the stomatal conductance and transpiration rate were the maximum. The ordinary supplementary light and Zhongkexicai supplementary light showed the same rule. In summary, temperature has a great influence on the photosynthesis of sweet cherry. Sweet cherry leaves need certain temperature conditions for photosynthesis. When the air temperature is lower than 15℃, some sweet cherry leaves may not produce effective photosynthesis. "Qizao" has the maximum photosynthesis when it is treated at 20℃, and "Meizao" has the maximum photosynthesis at 25℃.

[0081] Table 2 Effects of different temperature treatments on photosynthesis of sweet cherry

[0082]

[0083]

[0084] 2.2 Effects of different supplementary lighting treatments on photosynthesis of sweet cherries in greenhouses

[0085] As can be seen from Table 3, there are certain differences in the light intensity measured by different fill-in lights. The light intensity measured by the Pengyun remote monitoring instrument S21A is the highest for the Zhongke Xicai fill-in light, and the weakest for the full-spectrum fill-in light. The internal and external light intensities of the leaf chamber measured by the LI-6400X portable photosynthesis instrument also show that the Zhongke Xicai fill-in light has the highest light intensity. "Qizao" and "Meizao" both showed the highest net photosynthetic rate under the Zhongke Xicai fill-in light, and the lowest intercellular CO2 concentration. Under the same power conditions, the light quality of ordinary fill-in lights is white light, that of Zhongke Xicai fill-in lights is red and blue light, and that of full-spectrum plant fill-in lights is biased towards white light. In summary, different fill-in lights have a great influence on the photosynthesis of sweet cherries. Comprehensive evaluation shows that the Zhongke Xicai fill-in light has the best fill-in effect.

[0086] Table 3 Effects of different supplementary lighting on photosynthesis of sweet cherry

[0087]

[0088] 2.3 Effects of different distances of supplementary lighting on photosynthesis of sweet cherries in greenhouses

[0089] It can be seen from Table 4 that different distances of supplementary light have a great influence on the photosynthesis of sweet cherry. Among them, the light intensity inside the leaf chamber of "Meizao" is the highest at a distance of 15 cm from the supplementary light, which is 423.66 μmol m -2 s -1, at this time, the net photosynthetic rate is the largest; at a distance of 120cm from the supplementary light, the light intensity is only 5.42% of that at 15cm, and the net photosynthetic rate gradually decreases as the distance increases. "Qizao" shows the same rule. At 20cm, the light intensity inside the leaf chamber is the largest, and the net photosynthetic rate, stomatal conductance, and transpiration rate are all the largest. At 120cm, the light intensity inside the leaf chamber is the weakest, the net photosynthetic rate is the lowest, and the intercellular CO2 concentration is the highest. In summary, different distances of supplementary light have a great influence on the photosynthesis of sweet cherries. The closer the distance to the supplementary light, the greater the light intensity, the higher the net photosynthetic rate, and the better the supplementary light effect. However, if the distance is too close, the high temperature of the supplementary light will burn the leaves. Therefore, the distance between the supplementary light and the leaves should be 20cm-80cm.

[0090] Table 4 Effects of different supplementary lighting on the photosynthetic rate of sweet cherry

[0091]

[0092] 2.4 Effects of different density supplementary lighting on photosynthesis of sweet cherries in greenhouses

[0093] As can be seen from Table 5, different densities of supplementary lights have a great influence on the light intensity and photosynthesis of sweet cherries in the greenhouse. The light intensity of a 1m×1.5m supplementary light at the same distance is only about 50% of that of a 1m×0.75m one. The net photosynthetic rate of "Qizao" and "Meizao" under low-density supplementary lights is almost 0. The increase in the density of supplementary lights significantly increases the net photosynthetic rate of sweet cherries. Under low-density supplementary lights, the intercellular CO2 concentration and transpiration rate are relatively high, and the leaf temperature is higher than that under high-density conditions. In summary, the density of supplementary lights will affect the photosynthesis of sweet cherries. Increasing the density of supplementary lights can effectively enhance the photosynthesis of sweet cherries. The KGB tree-shaped "Qizao" has the best supplementary lighting efficiency when a 1m×0.75m density supplementary light is installed.

[0094] Table 5 Effects of different supplementary light densities on the photosynthetic rate of sweet cherry

[0095]

[0096]

[0097] 2.5 Effects of different lighting treatments on the quality of sweet cherry fruits in greenhouses

[0098] As can be seen from Table 6, different supplementary lighting treatments have a great impact on the quality of sweet cherry fruit. The single fruit weight of "Qizao" and "Meizao" is the largest under the Zhongkexicai supplementary lighting; the soluble solid content is also the largest under the rare earth supplementary lighting, among which the soluble solid content of Qizao can reach 20.05%; compared with the control, the rare earth supplementary lighting treatment can reduce the total acid content and increase the fruit solid-acid ratio. In summary, the Zhongkexicai supplementary lighting has the best comprehensive effect, and the fruit quality is better than the control and full-spectrum supplementary lighting treatments.

[0099] Table 6 Effects of different supplementary lighting on sweet cherry fruit quality

[0100]

[0101] 3. Conclusion

[0102] The present invention studies the temperature of sweet cherry leaves under different temperature conditions and finds that when the leaves are in a low temperature environment of 10°C, the leaves still maintain a temperature of more than 15°C. It is difficult for sweet cherries to grow normally in a low temperature environment for a long time. Sweet cherry leaves require certain temperature conditions for photosynthesis. The photosynthesis of sweet cherries "Qizao" and "Meizao" under 10°C low temperature treatment conditions is lower than that of other treatments. The net photosynthetic rate of "Qizao" reaches a maximum value at 20°C. As the temperature further increases, although the leaf temperature, stomatal conductance, transpiration rate, etc. all increase to varying degrees, its net photosynthetic rate decreases to a certain extent, which may be caused by its strong respiration. Sweet cherry photosynthesis is affected by many factors such as temperature, light intensity, stomatal conductance, CO2 concentration, etc. The net photosynthetic rate of "Meizao" reaches a maximum value at 25°C. From a low temperature environment of 10°C to 25°C, its net photosynthetic rate increases with the increase of temperature. Treatments T1-T4 were all dark conditions and supplemented with ordinary fill lights and Zhongkexicai fill lights. The light intensity was weaker than natural light. Studies have shown that under 10℃ low temperature treatment conditions, there is a certain degree of net photosynthetic rate, and its photosynthesis gradually increases with the continuous increase in temperature. If the temperature continues to rise, it will strengthen respiration, resulting in a continuous decrease in net photosynthetic rate. The above research can provide a certain reference for temperature control in off-season cultivation of sweet cherries, that is, "Qizao" has stronger adaptability to low temperature and weak light, and "Qizao" can be maintained at 20℃ at night; "Meizao" is more suitable for medium and high temperature management, and Meizao can be maintained at 25℃ at night.

[0103] Through the study of three different light quality fill-in lamps, the present invention found that the Zhongkexicai fill-in lamp has the highest fill-in efficiency among the three fill-in lamps. Its light intensity can reach 3060Lux at a distance of 80cm from the light source. At this time, the net photosynthetic rate of "Qizao" can reach 4.46μmol CO2 m -2 s -1. Compared with red and blue monochromatic light, the appropriate ratio of red to blue light can effectively promote the leaf development of plants and improve photosynthetic capacity. In this experiment, the net photosynthetic rate of sweet cherry was the highest when the red to blue light ratio (R / B) of Zhongkexicai supplementary light was 1.8. Due to the heavy rainfall and short light duration in spring and summer in southern China, the light in the greenhouse is often low and the humidity is high. The application of supplementary lights can not only effectively supplement light, but also reduce the humidity in the greenhouse to a certain extent, solving the problem of sweet cherry cracking rate in southern China.

[0104] Studies have shown that as the height of the supplementary light increases, the light intensity decreases. During the experiment, it was also found that the distance of the supplementary light would have a great impact on the light intensity and net photosynthetic rate of sweet cherries. The net photosynthetic rate of "Qizao" is close to 0 when the supplementary light distance is 100cm, and the net photosynthetic rate of "Meizao" is negative at 100cm. If the supplementary light distance is too close, it will cause high temperature burns to the leaves of sweet cherries. Therefore, the supplementary light distance of off-season sweet cherries should be ≤100cm, so as to produce an effective supplementary light effect. Generally speaking, the supplementary light of fruits and vegetables is 30cm-120cm away from the leaf surface, and the distance between the lights is 3m. However, previous experimental studies have shown that the net photosynthetic rate is lower under different temperatures and light quality conditions when the supplementary light density is low (1m×1.5m). Therefore, appropriately increasing the supplementary light density (1m×0.75m) is an effective way to promote photosynthesis of sweet cherries. After years of observation and experimentation, the KGB tree shape is one of the tree shapes suitable for cultivation in the southern region. In this experiment, the density of the supplementary light is more suitable at 1m×0.75m. In the experiment, the light intensity on the upper and bottom parts of the tall and slender spindle-shaped "Meizao" tree is relatively weak, and it is more appropriate to arrange the supplementary light in a staggered manner.

[0105] The present invention found that the fruit quality of off-season sweet cherries has been greatly improved, and the soluble solids content of "Qizao" exceeds that of conventional cultivation. Different light quality supplementary lighting will have a great impact on the quality of the fruit. In the present invention, the fruit quality of the Zhongke Xicai supplementary lighting lamp with a red light to blue light ratio (R / B) of 1.8 is the best, with high soluble solids content, low total acid content, rich fruit flavor, and significantly higher quality than ordinary supplementary lighting. Sweet cherry cultivation in the southern region faces many problems, among which the high temperature problem in summer is particularly prominent, which not only limits the off-season cultivation of sweet cherries, but also has an adverse effect on rain shelter and shade cultivation. "External shading and internal supplementary lighting" is an effective way to solve the high temperature problem during the fruit ripening period in the southern region.

[0106] The above is a description of the embodiments of the present invention. Through the above description of the disclosed embodiments, professionals and technicians in the field can implement or use the present invention. Various modifications to these embodiments will be apparent to professionals and technicians in the field. The general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown in this article, but will conform to the widest range consistent with the principles and novelties disclosed herein.

Claims

1. A method for delayed cultivation of sweet cherries in off-season suitable for southern regions, characterized in that: The method comprises the following steps: 1) Choose sweet cherry varieties that are suitable for growing in the southern region and are resistant to high temperatures; 2) Off-season cultivation greenhouses, with light-shielding rubber-plastic insulation cotton covering the outside of the greenhouse, and intelligent artificial environment control units inside the greenhouse to regulate temperature and humidity in the off-season cultivation greenhouse; 3) During the dormant period from April to May, the plants are cooled and dormant, and the temperature in the greenhouse is controlled at 2-4°C without light; 4) During the budding period in May, gradually increase the temperature, turn on the heat insulation cotton, and control the temperature in the greenhouse at 10-20℃; 5) During the flowering period from May to June, simulate the normal temperature in spring and control the temperature in the greenhouse at 12-25℃; 6) During the young fruit stage from mid-June to early July, the temperature in the greenhouse was controlled at 20-25℃, and supplementary lights and natural light were used for photosynthesis; the supplementary lights used were Zhongkexicai supplementary lights, with a red-blue light ratio of 1.8, and 1 m×0.75 m high-density supplementary lights were used for supplementary lighting. The supplementary lights were 20cm to 80cm away from the leaves. During the supplementary period, the temperature of the off-season cultivation greenhouse was controlled in the range of 20℃ to 25℃; the lighting duration was controlled to be 15-18 hours per day, and the supplementary lights were automatically turned on when the natural light was lower than 930 Lux; 7) During the maturity period from July to August, the temperature in the greenhouse should be controlled at 18-28℃; 8) After harvesting in September and October, the refrigerator does not need to be turned on, the insulation cotton is opened, all greenhouse films are opened, normal management is carried out, and fertilizer and water management is strengthened.

2. The method according to claim 1, characterized in that: The sweet cherry varieties that can withstand high temperatures are "Qizao" or "Meizao".

3. The method according to claim 2, characterized in that "Qizao" is a 5-year-old KGB tree shape, and "Meizao" is a 4-year-old tall and slender spindle tree shape.

4. The method according to claim 2, characterized in that: During the young fruit stage, the temperature in the "Qizao" off-season cultivation greenhouse is regulated at 20℃, and the temperature in the "Meizao" off-season cultivation greenhouse is regulated at 25℃.

5. The method according to claim 1, characterized in that The method according to claim 1 is characterized in that the off-season cultivation greenhouse is a single arch shed with a length of 40 m and a width of 11 m, and the outside of the shed is covered with 5 cm thick rubber-plastic insulation cotton.

6. The method according to claim 1, characterized in that The power of Zhongkexicai fill-in light is 60 W, the main wavelength is 699.0nm, the luminous flux is 4030.42 1m, and the fill-in light time is from 6:00 to 22:00 every day.

7. The method according to claim 1, characterized in that The installation height of the fill light is 40 cm to 120 cm, and it is arranged in a staggered manner according to the different tree shapes to ensure the uniformity of sweet cherry photosynthesis.

8. The method according to claim 1, characterized in that Fertilization management includes applying urea, potassium dihydrogen phosphate and trace element fertilizers, supplementing nutrients in stages to ensure the improvement of leaf photosynthetic efficiency and fruit quality.

9. The method according to claim 1, characterized in that: Real-time monitoring of the temperature, humidity and light intensity in the greenhouse is carried out through remote monitoring instruments to ensure that the growth environment of sweet cherries is always in the best condition.

10. The method according to claim 1, characterized in that Through off-season cultivation methods, ripe fruits can be obtained in July and August.

Images