Feizixiao anti-season in-vitro flowering method for alpine rhododendron

Abstract

The invention relates to an anti-season in-vitro flowering method of Rhododendron lapponicum 'Feizixiao', which comprises the following steps of: catalyzing branch cutting anti-season flowering of Rhododendron lapponicum 'Feizixiao' through pretreatment, collection, refrigeration and culture, and determining the flowering time of Rhododendron lapponicum 'Feizixiao' according to indexes such as time required from warehouse-out to flowering, branch openness, inflorescence openness, inflorescence size, single flower size, vase life and the like. And the optimal method for Feizixiao branch cutting in-vitro anti-season flowering of the alpine rhododendron is determined. The Feizixiao branch cutting in-vitro anti-season flowering method for the Rhododendron lapponicum is simple to operate and easy to implement, a new application form is provided for the Rhododendron lapponicum, and the variety of winter woody cut flowers in China is enriched.

Description

Technical Field

[0001] This invention relates to the field of plant cultivation technology, specifically to a method for off-season detached flowering of the alpine rhododendron 'Guifei Zuijiu'. Background Technology

[0002] alpine rhododendron ( Rhododendron Rhododendron (L.) is a world-renowned woody ornamental plant and one of my country's ten famous flowers. With people's increasing pursuit of a beautiful life, potted alpine rhododendrons are flourishing in the domestic flower market as New Year's flowers. In recent years, cut flowers of domestically bred alpine rhododendron varieties such as 'Guifei Zuijiu', 'Kunshang Chuhong', and 'Baochai' have begun to appear in the domestic market as niche cut flowers and have received a good response. As is well known, Yunnan is the largest production, trading, and export base for cut flowers in China and even Asia. Developing and industrializing alpine rhododendron cut flower technology will greatly promote the innovative and high-quality development of Yunnan's cut flower industry, especially its distinctive cut flower industry.

[0003] Currently, cut branches of self-bred varieties such as 'Guifei Zuijiu' (meaning "Drunken Concubine") alpine rhododendrons are sold during their natural flowering period, March and April, with no winter-flowering cut branches yet available. While winter is the peak season for cut flower sales as the year draws to a close, climate factors limit the variety of available species, especially woody flowering plants. Developing a method for off-season, detached flowering of the 'Guifei Zuijiu' alpine rhododendron would not only increase the variety of winter woody cut flowers but also broaden the application of Lunar New Year-end alpine rhododendrons.

[0004] The flower buds of alpine rhododendrons are dormant in winter, and breaking this dormancy to induce normal flowering is a key technical challenge in this field. Existing off-season forcing techniques for alpine rhododendrons typically involve potted plants (Liu Xiaoqing, Su Jiale, Li Chang, et al. Comparative study on the flowering effects of alpine rhododendron varieties during the Spring Festival [J]. Jiangsu Agricultural Sciences, 2013, 41(09): 167-168), but off-season forcing treatment using cut branches has not yet been observed. Unlike forcing flowering of potted plants, cut branches lose the nutrient supply from the mother plant after being removed from the plant, which leads to limited physiological functions, resulting in failure to flower or abnormal flowering and a shorter lifespan.

[0005] Therefore, finding a practical method for off-season flowering of dormant rhododendron cuttings is a key issue to be addressed in the field of winter cut rhododendron flowers. Summary of the Invention

[0006] To overcome the problems existing in the background technology, this application provides a method for off-season detached flowering of alpine rhododendron 'Guifei Zuijiu'. Through techniques such as flower branch cultivation, pruning, cold storage, and heating, off-season detached flowering of alpine rhododendron 'Guifei Zuijiu' cut branches is achieved. The operation is simple and easy to implement, and it can provide a new variety for the winter cut flower market.

[0007] To achieve the above objectives, the present invention is implemented through the following technical solution: The method for off-season detached flowering of the alpine rhododendron 'Guifei Zuijiu' includes the following specific steps: (1) Pretreatment: Select plants and perform maintenance and light management from February to October; (2) Collection: In October-November, cut flower branches with flower buds from the pretreated plants and disinfect them; (3) Refrigeration: Insert the disinfected flower branches into clean water and refrigerate them at 7°C in the dark for 35-42 days; (4) Cultivation: Take out the flower branches after cold storage cultivation, insert them into a container containing preservative, and cultivate them at a temperature of 23℃, light intensity of 1500 lx, light duration of 14 h / day, and humidity of 70%-90% until flowering. The preservative is: 1.50 g / L sucrose + 350 mg / L 8-HQC.

[0008] Further optimization is made by the following step (1): the plant is a 2-gallon potted alpine rhododendron that is growing well without pests or diseases, has a growth period of more than 3 years, and has reached the flowering period.

[0009] Further preferably, in step (1), the maintenance management method includes: (1) In early February, select plants with a ground diameter of 1.2-1.5cm, retain 2 primary branches on each plant and pinch off the tips; (2) In early April, retain two new shoots on each primary branch, wherein the new shoots are longer than 20 cm and thicker than 0.6 cm; (3) During the period from mid-April to early May, spray the flower bud induction solution once every 10 days. When spraying, make sure that the front and back of the leaves are evenly moist but not dripping. The flower bud induction solution is prepared by dissolving 0.1 g / L of acetamiprid and 1 g / L of potassium dihydrogen phosphate in water.

[0010] Further preferred, in step (1), the light management method includes: during the period from August to October, the plants are shaded using a shading net with a shading rate of 50% from 12:00 to 17:00 every day, and are given full light treatment during the rest of the time.

[0011] Further preferred, in step (2), the diameter of the flower bud is 1.80-2.10cm; the length of the flower branch is 35cm and the thickness is 0.90-1.20cm.

[0012] Further preferred, in step (2), the cutting method is to retain only 3-5 leaves below the top of the flower branch, and remove the axillary buds below the petiole of the flower branch and the dormant buds below the flower bud.

[0013] Further preferred, in step (2), the disinfection method is to soak the flower branches in a thiophanate-methyl aqueous solution for 30 minutes, wherein the mass concentration of the thiophanate-methyl aqueous solution is 1-1.25 g / L.

[0014] Further preferred, in step (3), the amount of clean water used is 100-400 mL.

[0015] Further preferred, in step (4), the amount of the preservative is such that it submerges the cut of the flower branch by 5 cm.

[0016] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application.

[0017] The beneficial effects of this invention are: 1. This application provides a method for off-season in vitro flowering of the alpine rhododendron 'Guifei Zuijiu'. This method involves taking dormant cuttings in autumn, subjecting them to cold storage and specific cultivation to induce flowering. The entire in vitro flowering method is simple to operate and easy to implement, enabling the off-season supply of alpine rhododendron cut flowers. This not only enriches the variety of woody cut flowers available in winter but also provides a new form of Lunar New Year product for the alpine rhododendron industry, increasing the added value of products for alpine rhododendron producers and promoting the industrial application of newly bred alpine rhododendron varieties.

[0018] 2. This application effectively improved the inflorescence, branch opening degree, and single flower size of dormant rhododendron cut branches by controlling the temperature and time of cold storage, and extended the vase life of the cut flowers. This is because appropriate cold storage time can promote the enhancement of amylase activity in the flower branches, promote the hydrolysis of starch into soluble sugars, and increase soluble proteins, thereby promoting the rhododendron cut branches to break dormancy and enter the flowering stage.

[0019] 3. This application demonstrates that immersing flower branches in clean water for wet storage significantly enhances the ornamental value of alpine rhododendron cut flowers. This is because cut branches undergo a series of aging-related physiological changes after harvesting, such as water imbalance, nutrient degradation, and cell disintegration. Water metabolism is crucial, and normal turgor pressure is essential for cells to maintain normal life activities. High water tension is fundamental for flower bud opening, and maintaining flower freshness also depends on a good water balance. Under wet storage conditions, the flower branches absorb water throughout the process, providing better cell turgor pressure for the flowers and maintaining the water balance of the branches. This, in turn, allows alpine rhododendron cut flowers to maintain good cut flower quality and ornamental value.

[0020] 4. This application significantly improved the inflorescence opening and color saturation of alpine rhododendron cut flowers by controlling the temperature and light during the flower branch cultivation period. This is because suitable temperature selection is conducive to starch decomposition and soluble sugar degradation inside the cut branches, accelerating dormancy breaking and improving flowering quality. At the same time, the alpine rhododendron 'Guifei Zuijiu' is a yellow-flowered variety, and 14 hours of light treatment can ensure the accumulation of carotenoids in the flowers, thus better maintaining its varietal characteristics.

[0021] 5. This application utilizes a specific preservative combination: 1.50 g / L sucrose + 350 mg / L 8-HQC, which significantly extends the cut flower life of the alpine rhododendron 'Guifei Zuijiu', achieving a vase life of 21±2 days. This is because sugar is an important nutrient in cut flowers. After being absorbed into the cut flower, sucrose is broken down into glucose and fructose, becoming a respiratory substrate and structural component of the plant. Simultaneously, sucrose can enter the flower along the vascular bundles, increasing the flower's osmotic concentration, improving water absorption capacity, and keeping the petals swollen. It also maintains the semi-permeability of the cell membrane, delaying the penetration of ions and water, thus contributing to extended lifespan and preserving petal color. 8-HQC, as a bactericide, readily binds to metal ions, removing iron and copper ions from bacteria, thereby exerting an antibacterial effect. It also lowers the pH of the water, promoting water absorption by the flowers. Attached Figure Description

[0022] Figure 1 This is a comparative example 4 of the application, showing the effect of cold storage and flower induction of alpine rhododendron cuttings; Note: 1. Front (top) and top (bottom) views of dormant cut branches flowering at 15℃; 2. Front (top) and top (bottom) views of dormant cut branches flowering at 23 / 15℃; 3. Front (top) and top (bottom) views of dormant cut branches flowering at 23℃.

[0023] Figure 2 This is a comparison image of the effect of cold storage and flower induction of alpine rhododendron cuttings in Example 5 of this application; Note: 1. Dormant cut branches that receive 8 hours of light will flower; 2. Dormant cut branches that receive 14 hours of light will flower. Detailed Implementation

[0024] To make the objectives, technical solutions, and beneficial effects of the present invention clearer, the preferred embodiments of the present invention will be described in detail below to facilitate understanding by those skilled in the art.

[0025] As a novel type of cut flower, there are very few reports on the cutting techniques of alpine rhododendrons. The only existing research focuses on the effects of different harvesting periods and preservatives on the vase arrangement of alpine rhododendron 'XXL' cut branches under natural flowering conditions (Jie Weijia, Song Jie, Peng Luchun, et al. Effects of different harvesting periods and preservatives on the vase arrangement of alpine rhododendron 'XXL' cut branches [J]. Shanxi Agricultural Sciences, 2024, 52(06):115-121). This study determined that the budding stage of alpine rhododendron 'XXL' under natural flowering conditions is the optimal harvesting period for cut branches. However, no research on the preservation of cut branches of other alpine rhododendron varieties has been found.

[0026] This invention provides a method for off-season detached flowering of the alpine rhododendron 'Guifei Zuijiu', which enables dormant alpine rhododendron cut branches to flower detached in winter. This not only provides a new variety for the winter woody cut flower market but also offers a new product form for the development of the alpine rhododendron industry and effectively promotes the industrial application of self-bred new varieties.

[0027] Unless otherwise specified, all reagents and materials used in the following examples were purchased from the market.

[0028] Example 1: (1) Pretreatment: Select robust, disease-free, and flowering 2-gallon potted alpine rhododendron 'Guifei Zuijiu' plants (this alpine rhododendron variety can be obtained from the Yunnan Academy of Agricultural Sciences Flower Research Institute) as materials. In early February, select plants with a ground diameter of 1.2-1.5 cm, retain two primary branches on each plant and pinch off the tips. In early April, retain two new shoots with a length greater than 20 cm and a diameter greater than 0.6 cm on each primary branch, and remove excess branches. From mid-April to early May, spray every 10 days. The flower bud induction solution should be applied once, ensuring that both sides of the leaves are evenly moistened without dripping. The flower bud induction solution is prepared by dissolving 0.1 g / L of paclobutrazol (produced by Sichuan Runer Technology Co., Ltd., with an effective ingredient content of 5%) and 1 g / L of potassium dihydrogen phosphate (produced by Sichuan Runer Technology Co., Ltd., with an effective ingredient content greater than 98%) in water. From August to October, the plants should be shaded with a 50% shade net from 12:00 to 17:00 daily. Unless otherwise specified, the plants should be exposed to full sunlight during other times. (2)Collection: On October 20, 2023, 48 dormant flower branches with flower buds of 'Drunken Concubine' were cut. The length of the cut branches was 35 cm, the thickness of the branches was 0.90 cm, the diameter of the flower buds was 1.80 cm. Excess leaves on the flower branches of each variety were removed, only 3 - 5 leaves below the top of the flower branch were retained, and the axillary buds under the petioles of the flower leaves and the dormant buds under the flower buds were removed. The flower branches were soaked in an aqueous solution of thiophanate-methyl (produced by Ruihua Bio-Agriculture Co., Ltd., Tangshan City, Hebei Province, with an active ingredient of 65%) for 30 minutes. The mass concentration of the thiophanate-methyl aqueous solution was 1.25 g / L. Then the flower branches were taken out and air-dried to complete the disinfection treatment; (3)Cold storage: The disinfected flower branches were inserted individually into a conical flask containing 150 mL of clear water, and then placed in a cold cabinet (produced by Zhejiang Xingxing Cold Chain Integration Co., Ltd., model LGC - 1500FS3), and cultured for 35 d at 7℃ under dark conditions; (4)Cultivation: On November 23, 2023, the dormant flower branches after cold storage cultivation were taken out. The flower branches were inserted individually into a conical flask containing a preservative, and it was ensured that 5 cm above the cut of the flower branch was immersed in the preservative. The preservative was: 1.50 g / L sucrose + 350 mg / L 8 - HQC. The flower branches were cultured in an artificial climate incubator (produced by BINDER GmbH, Germany, model KBWF720) at a temperature of 23℃, a light intensity of 1500 lx, a light duration of 14 h / day, and a humidity of 70% - 90% until they bloomed; (5)Vase - inserting: The flower branches were taken out from the artificial climate incubator and vase - inserted for daily maintenance and viewing.

[0029] The soluble sugar content and starch content of the leaves of the dormant cut branches of Rhododendron lapponicum 'Drunken Concubine' after pretreatment were within the range of 50 - 80 mg / g, which could provide sufficient nutrition for the subsequent in vitro flowering of the dormant cut branches. In addition, as shown in Table 1, there were significant differences in the vase - inserting life and branch opening degree between the flowering trait indexes of the dormant cut branches of 'Drunken Concubine' treated by the method of this embodiment and natural flower branches, but there were no significant differences in the inflorescence opening degree, inflorescence size and single - flower size between them and natural flower branches, indicating that using this method could make the dormant cut branches achieve a better flowering effect.

[0030] Table I Comparison of the off - season in vitro flowering technology of the dormant cut branches of Rhododendron lapponicum 'Drunken Concubine' and its natural flowering traits Note: Time from removal from storage to flowering (d) = Time for the first flower to open - Time removed from the freezer; Vase life (d) = Time for the last flower to wither - Time for the first flower to open; Branch opening rate (%) = Number of flowering branches / Total number of branches in the experiment × 100%; Inflorescence opening rate (%) = Number of flowers open on a single inflorescence / Total number of flowers in the inflorescence × 100%; Inflorescence size (cm) = Width of inflorescence opening on a single branch (cm); Single flower size (cm) = Width of flower opening (cm); The same letter between data of the same trait indicates no significant difference (P > 0.05), and different letters indicate significant differences (P < 0.05).

[0031] Comparative Example 1: (Temperature control for refrigerated cuttlefish) In this comparative example, dormant cuttings of the alpine rhododendron 'Guifei Zuijiu' were stored at 15°C and 7°C for 35 days, respectively, with all other conditions being consistent with the steps in Example 1.

[0032] As shown in Table 2, the branch opening degree, inflorescence opening degree, inflorescence size, and single flower size of dormant cuttings refrigerated at 7℃ were significantly better than those refrigerated at 15℃. The vase life was also as high as 15 days, far exceeding the 7 days of refrigeration at 15℃. Low-temperature treatment can hydrolyze starch and accumulate soluble sugars in dormant rhododendron cuttings. 15℃ is the average temperature in Yunnan from October to November. The experimental results show that this temperature is insufficient to meet the low-temperature requirements of dormant cuttings. The 7℃ low-temperature treatment, compared to 15℃, resulted in the accumulation of more soluble sugars, which can promote better subsequent flowering of the rhododendron cuttings.

[0033] Table 2. Effects of different refrigeration temperatures on off-season in vitro flowering of dormant cut branches of Rhododendron 'Guifei Zuijiu'. Note: Data with the same letter for the same trait indicate no significant difference (P>0.05), while data with different letters indicate significant differences (P<0.05).

[0034] Comparative Example 2: (Comparison of refrigeration time for cuttlefish) In this comparative example, cut branches of the alpine rhododendron 'Guifei Zuijiu' were refrigerated in a refrigerator at 7°C for 28 days, 35 days, and 42 days, with all other conditions being the same as in Example 1.

[0035] As shown in Table 3, there were no significant differences in any of the indicators between the two treatments when the cut branches were cold-stored for 35 days and 42 days. However, the cut branches cold-stored for 35 days and 42 days showed significantly better results in all indicators except for vase life compared to those cold-stored for 28 days. Although the vase life of the alpine rhododendron cut flowers was 21 days after 28 days of cold storage, which was significantly higher than the other two treatments, its inflorescence opening rate was only 71.75%, resulting in uneven flowering and a lack of ornamental value.

[0036] Therefore, cuttings of the alpine rhododendron 'Guifei Zuijiu' should be refrigerated at 7℃ for 35-42 days to achieve a more balanced state in terms of both aesthetic appeal and vase life.

[0037] Table 3. Effects of different refrigeration times on off-season in vitro flowering of dormant cut branches of Rhododendron 'Guifei Zuijiu' Note: Data with the same letter for the same trait indicate no significant difference (P>0.05), while data with different letters indicate significant differences (P<0.05).

[0038] Comparative Example 3: (Comparison of refrigeration methods for cuttlefish) In this comparative example, dormant cuttings of the alpine rhododendron 'Guifei Zuijiu' were divided into two portions. One portion was subjected to dry storage treatment, i.e., the dormant cuttings were wrapped in styrofoam and placed in a plastic bag and tied tightly. The other portion was subjected to wet storage treatment, i.e., the dormant cuttings were placed in a triangular conical flask containing 150 mL of water. All other conditions were the same as in Example 1.

[0039] After cutting and harvesting, branches undergo a series of aging-related physiological changes, such as water imbalance, nutrient degradation, and cell disintegration, with water metabolism being crucial. Normal turgor pressure is essential for cells to maintain normal life activities, and high water tension is the basis for flower bud opening. Maintaining freshness also depends on a good water balance.

[0040] As shown in Table 4, the fresh weight change rate of dormant cut branches treated with wet storage was -1.37%, while that of dormant cut branches treated with dry storage was -12.34%. The fresh weight of dormant cut branches treated with wet storage was significantly higher than that of those treated with dry storage, indicating that the former had a significantly better effect on maintaining turgor pressure than the latter.

[0041] In terms of flowering, the dormant cut branches treated with moist storage showed significantly higher rates of branch opening, inflorescence opening, inflorescence size, and individual flower size compared to those treated with dry storage, indicating that moist storage is crucial for the normal flowering of alpine rhododendron cut branches. Regarding vase life, the inflorescences of dry storage flowered at different times, and although the overall vase life was 18 days, significantly longer than the 15 days of moist storage, it lacked visual appeal. Therefore, moist storage is more beneficial for promoting flowering of dormant alpine rhododendron cut branches.

[0042] Table 4. Effects of different refrigeration methods on off-season in vitro flowering of dormant cut branches of Rhododendron 'Guifei Zuijiu' Note: Fresh weight change rate (%) at the time of leaving the warehouse = (fresh weight of cut branches at the time of leaving the warehouse - fresh weight of cut branches at the time of entering the warehouse) / fresh weight of cut branches at the time of entering the warehouse × 100%; the same letter between data of the same trait indicates no significant difference (P>0.05), and different letters indicate significant difference (P<0.05).

[0043] Comparative Example 4: (Control of flower branch cultivation temperature) In this comparative example, dormant cuttings of the alpine rhododendron 'Guifei Zuijiu' were cultured at 15℃ (24h / d), 23℃ (12h / d) / 15℃ (12h / d), and 23℃ (24h / d), respectively, with all other conditions being consistent with the steps in Example 1.

[0044] As shown in Table 5 and Figure 1 As shown, at a temperature of 23℃, the inflorescence opening degree of rhododendron cuttings was the highest, the single flower was the largest, and the time required from removal from storage to flowering was the shortest. Temperature plays an important role in plant growth; increasing the temperature is beneficial for plants to continuously synthesize cytokinins and transport them upwards, thereby breaking dormancy earlier and promoting growth. For detached dormant rhododendron cuttings, higher temperatures are conducive to starch decomposition and soluble sugar degradation, accelerating dormancy breaking and improving flowering quality. Therefore, the temperature condition of 23℃ selected in this application is a better treatment method for cultivating rhododendron cuttings.

[0045] Table 5. Effects of different cultivation temperatures on off-season in vitro flowering of dormant cut branches of Rhododendron 'Guifei Zuijiu'. Note: Data with the same letter for the same trait indicate no significant difference (P>0.05), while data with different letters indicate significant differences (P<0.05).

[0046] Comparative Example 5: (Comparison of light duration for flower branch cultivation) This comparative example involves cultivating dormant cuttings of the alpine rhododendron 'Guifei Zuijiu' under light durations of 8 h / day and 14 h / day, respectively, with all other conditions being consistent with the steps in Example 1.

[0047] As shown in Table 6 and Figure 2 As shown, there were no significant differences in inflorescence opening degree, inflorescence size, and single flower size between the two treatments. However, under a light treatment of 14 h / day, the flower color saturation of cut branches of the alpine rhododendron 'Guifei Zuijiu' was significantly higher than that under a light treatment of 8 h / day. The study indicates that carotenoids are one of the basic substances responsible for the yellow to red color of petals and play an important role in flower color formation. Under low light conditions, the accumulation of carotenoids in petals decreases, leading to a paler flower color. The alpine rhododendron 'Guifei Zuijiu' is a yellow-flowered variety, and a light treatment of 14 h / day effectively preserved its varietal characteristics.

[0048] Table 6. Effects of different light durations on off-season in vitro flowering of dormant cut branches of the alpine rhododendron 'Guifei Zuijiu' Note: Data with the same letter for the same trait indicate no significant difference (P>0.05), while data with different letters indicate significant differences (P<0.05).

[0049] Comparative Example 6: (Screening of Preservatives) This comparative example involved cultivating dormant cuttings of the alpine rhododendron 'Guifei Zuijiu' in different preservatives. All preservative combinations are shown in Table 9, and other conditions were consistent with those in Example 1.

[0050] Based on flowering quality indicators such as vase life (d), number of flowers (flowers), inflorescence size (cm), and single flower size (cm), an analytic hierarchy process (AHP) was constructed to determine the weight of each indicator (see Table 7). Then, each treatment was scored (P) according to the trait grading criteria (see Table 8). The score (C) of each indicator was multiplied by the corresponding weight (W) to calculate the comprehensive trait score (P') of each preservative solution.

[0051] Table 7 Weight values ​​of various traits of flowering on cut branches of Rhododendron alpineum Note: Number of flowers (flowers) = Number of flowers in a single inflorescence.

[0052] Table 8. Grading Criteria for Flowering Characteristics of Rhododendron Cut Branches Table 9. Comparison of vase arrangement effects of Rhododendron 'Guifei Zuijiu' under different preservative treatments Note: 8-HQC: 8-hydroxyquinoline citrate; CA: citric acid.

[0053] Table 9 shows that different preservative formulations significantly affected the vase life of cut branches of the alpine rhododendron 'Guifei Zuijiu'. In terms of vase life, cut branches treated with T8, T16, T14, T9, and T10 all exhibited good vase life, reaching 21 days. Considering flowering quality factors such as the number of flowers, inflorescence size, and individual flower size, treatment T8 was the best, followed by T16. Therefore, this application selected treatment T8, i.e., 1.50 g / L sucrose + 350 mg / L 8-HQC, as the preservative formulation.

[0054] The various embodiments of this application have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical application, or improvement of the technology in the market, or to enable others skilled in the art to understand the embodiments disclosed herein.

Claims

1. A method for off-season detached flowering of the alpine rhododendron 'Guifei Zuijiu', characterized in that, The method includes the following steps: (1) Pretreatment: Select plants and perform maintenance and light management from February to October; (2) Collection: In October-November, cut flower branches with flower buds from the pretreated plants and disinfect them; (3) Refrigeration: Insert the disinfected flower branches into clean water and refrigerate them at 7°C in the dark for 35-42 days; (4) Cultivation: Take out the flower branches after cold storage cultivation, insert them into a container containing preservative, and cultivate them at a temperature of 23℃, light intensity of 1500 lx, light duration of 14 h / day, and humidity of 70%-90% until flowering. The preservative is: 1.50 g / L sucrose + 350 mg / L 8-HQC.

2. The method according to claim 1, characterized in that, In step (1), the plant is a 2-gallon potted alpine rhododendron that is growing well without pests or diseases, has a growth period of more than 3 years, and has reached the flowering period.

3. The method according to claim 1, characterized in that, In step (1), the maintenance and management method includes: (1) In early February, select plants with a ground diameter of 1.2-1.5cm, retain 2 primary branches on each plant and pinch off the tips; (2) In early April, retain two new shoots on each primary branch, wherein the new shoots are longer than 20 cm and thicker than 0.6 cm; (3) During the period from mid-April to early May, spray the flower bud induction solution once every 10 days. When spraying, make sure that the front and back of the leaves are evenly moist but not dripping. The flower bud induction solution is prepared by dissolving 0.1 g / L of acetamiprid and 1 g / L of potassium dihydrogen phosphate in water.

4. The method according to claim 1, characterized in that, In step (1), the light management method includes: from August to October, the plants are shaded using a shading net with a shading rate of 50% during the period from 12:00 to 17:00 every day, and are given full light treatment during the rest of the time.

5. The method according to claim 1, characterized in that, In step (2), the diameter of the flower bud is 1.80-2.10cm; the length of the flower branch is 35cm and the thickness is 0.90-1.20cm.

6. The method according to claim 1, characterized in that, In step (2), the cutting method is to retain only 3-5 leaves below the top of the flower branch, and remove the axillary buds below the petiole of the flower branch and the dormant buds below the flower bud.

7. The method according to claim 1, characterized in that, In step (2), the disinfection method is to soak the flower branches in a thiophanate-methyl aqueous solution for 30 minutes, wherein the mass concentration of the thiophanate-methyl aqueous solution is 1-1.25 g / L.

8. The method according to claim 1, characterized in that, In step (3), the amount of clean water used is 100-400 mL.

9. The method according to claim 1, characterized in that, In step (4), the amount of preservative used is such that it submerges the cut of the flower branch by 5 cm.

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