Method for year-round propagation of jujube tissue culture seedlings by cuttings and rapid seedling formation, flowering and fruiting

Abstract

The present invention relates to the technical field of fruit tree cultivation, and discloses a method for year-round propagation of jujube tissue culture seedlings by cuttings and rapid seedling formation, flowering and fruiting. The method comprises the following steps: culturing the tissue culture seedlings with a culture medium, removing the unrooted jujube tissue culture seedlings for cuttings, transplanting the surviving tissue culture seedling cuttings, managing water and fertilizer, temperature, humidity and light, and applying exogenous growth regulators, promoting the rapid growth of the tissue culture seedling cuttings into large seedlings and flowering and fruiting, taking the large jujube seedlings for hanging cuttings to obtain second-generation tissue culture seedling cuttings, and taking the second-generation cuttings for hanging cuttings to obtain third-generation tissue culture seedling cuttings. The present invention can enable the "jujube tissue culture seedlings" to take root and survive directly in the substrate without the process of rooting and hardening the seedlings in the culture medium, and quickly form seedlings, flowering and fruiting, avoiding a series of problems such as the strict requirements for field hardening of traditional tissue culture seedlings and a low seedling survival rate, and achieving rapid and efficient seedling formation; and can enable the "jujube tissue culture seedlings" cuttings to bloom and fruit in the same year, shortening the breeding period. This invention is of great significance for accelerating the breeding process of jujube trees and provides support for the acquisition of asexual seedlings and rootstocks.

Description

Technical Field

[0001] The invention relates to the technical field of fruit tree cultivation, in particular to a method for year-round propagation of jujube tissue culture seedlings through cuttings and rapid seedling formation, flowering and fruiting. Background Art

[0002] Jujube, a major fruit tree native to my country, is one of the country's five dominant economic forest species and a vital source of income for nearly 20 million farmers. The development of the jujube industry has significantly promoted rural revitalization and boosted my country's socioeconomic growth. Jujube trees primarily reproduce through sexual (seed) and asexual propagation. Seed propagation produces robust, adaptable trees, but seed propagation can easily lead to plant variation. Therefore, to maintain high quality, asexual propagation methods, including cuttings, grafting, and tissue culture, are often used in jujube production.

[0003] Jujube tissue culture technology faces a series of challenges in practical production, including rooting difficulties, low transplant survival rates, and difficulty sterilizing explants, hindering its practical application. Cuttings, also known as cuttings, are a widely used asexual propagation method. The specific procedure involves cutting plant stems, leaves, roots, buds, and other organs, soaking them in plant growth regulators (auxins), and allowing them to root and plant, creating independent new plants. However, this method suffers from a low seedling success rate and a long cycle from tissue culture seedlings to flowering and fruiting, hindering both the breeding process of jujube trees and the efficiency of obtaining clones and rootstocks.

[0004] Therefore, it is necessary to provide a method for year-round propagation of jujube tissue culture seedlings by cuttings and rapid seedling formation, flowering and fruiting. The method utilizes jujube cutting technology to establish a technical system from tissue culture seedling cutting rooting to rapid seedling formation and then to tissue culture seedling flowering and fruiting, which is of great significance for improving production efficiency, cultivating asexual seedlings and early high-quality stable asexual rootstocks. Summary of the Invention

[0005] The present invention aims to provide a method for year-round propagation of jujube tissue culture seedlings by cuttings and rapid seedling formation, flowering and fruiting. The method cultivates complete jujube seedlings by cutting unrooted jujube tissue culture seedlings obtained from a culture medium, thereby achieving rapid and efficient growth into large seedlings, while simultaneously achieving flowering and fruiting in the same year, accelerating the breeding process of asexual large seedlings, and obtaining a large number of asexual seedlings and rootstocks with stable and high-quality traits.

[0006] The technical methods adopted in the present invention are as follows:

[0007] The present invention provides a method for year-round propagation of jujube tissue culture seedlings by cuttings and rapid seedling formation, flowering and fruiting, comprising the following steps:

[0008] (1) The jujube tissue culture seedlings Y①-1 type after 45 days of culture in MS medium were used as cutting materials. Later, the types of jujube tissue culture seedlings were expanded to 35 more types of jujube tissue culture seedlings as cutting materials. The tissue culture seedlings with the same size and strong growth in the culture medium were selected as cuttings.

[0009] (2) Take out the tissue culture seedlings from the culture medium, remove the proliferative part at the base and the bottom leaves, leaving about 0.5 cm at the bottom and 3-4 leaves at the top. The overall cutting length is 4-5 cm.

[0010] (3) Soak the treated tissue culture seedling cuttings in 1.25g / L carbendazim solution for 5 minutes, dip them in 1000mg / L IBA solution for 10 seconds, insert the lower end of the cuttings into the prepared cutting medium, and place them in a light incubator at 25-30℃, 95% humidity, and 6000lx for rooting.

[0011] (4) When the above-mentioned tissue culture seedlings take root, the roots break through the hole tray, and the above-ground part begins to grow, transplant the jujube tissue culture seedlings of basically the same size and strong growth into a seedling pot with a diameter of 25 cm. Select the seedling medium: earthworm castings: peat: perlite = 3:2:1:1 as the culture medium for large seedlings, supply water and fertilizer adequately, spray CGMP every 7 days, apply 1000 times liquid starch-dissolving microbial fertilizer once every 10 days, and apply 0.88g / L Hogland nutrient solution once every 30 days.

[0012] (5) The tissue culture seedling cuttings began to grow rapidly 20 days after transplantation, and began to branch in large numbers 30 days later. The average height of the cuttings was 15 cm, which was defined as the first generation of tissue culture seedling cuttings.

[0013] (6) When the first generation of tissue culture seedlings (without pinching) grow to an average plant height of 46 cm and an average stem diameter of 3.13 mm, flower buds begin to appear on the cuttings; when the first generation of tissue culture seedlings (with pinching) grow to an average plant height of 21 cm and an average stem diameter of 2.67 mm, flower buds begin to appear on the cuttings, spray potassium dihydrogen phosphate solution on the leaves every 15 days, apply 1000 times liquid starch-dissolving microbial fertilizer once every 10 days, and spray 30 mg / L gibberellin solution once every 7 days to promote their abundant flowering and fruit setting.

[0014] (7) Cuttings from the first generation tissue culture seedling cuttings to obtain the second generation tissue culture seedling cuttings.

[0015] (8) Cut the tender branches of the second-generation tissue culture seedlings as cuttings, and then carry out cuttings to obtain the third-generation tissue culture seedlings.

[0016] Furthermore, in step (1), the jujube tissue culture seedlings are cultured in MS culture medium at an ambient temperature of 20° C., a humidity of 45%, and a light intensity of 3000 lx.

[0017] Furthermore, in step (2), the proliferative portion of the tissue culture seedlings grown in the MS medium for 45 days needs to be cut off before cutting.

[0018] Furthermore, in step (3), the cutting substrate is peat:perlite=3:1, and the cutting substrate needs to be disinfected with 1.25g / L carbendazim solution according to the weight of the substrate before use (substrate:carbendazim solution=1100g:1L).

[0019] Furthermore, in step (3), the cutting base should be reduced from breaking during the cutting process, and after the cutting is completed, the cuttings should be ensured to be perpendicular to the substrate to reduce lodging so as to improve the cutting survival rate and ensure the normal upward growth of the cuttings after transplanting.

[0020] Furthermore, the transplanting of cuttings into large seedlings in steps (4) and (5) is carried out in an artificial climate control room, with environmental conditions of 25-30°C during the day and 20-25°C at night, a light intensity of 6000 lx, and a photoperiod of 16h / 8h.

[0021] Furthermore, in step (6), the top of the jujube tissue culture seedlings is pinched to remove the terminal buds of the jujube seedlings. After the flower buds appear on the cutting seedlings, they are moved into an artificial climate control room with an environmental condition of 23-25°C during the day and 16-18°C at night, a light intensity of 20,000 lx, and a photoperiod of 16h / 8h.

[0022] Furthermore, in step (7), healthy and uniformly growing cuttings are selected from the first generation tissue culture seedlings, and tender shoots of the cuttings are cut from the same position for cutting. Cuttings with a length of 8-10 cm and 15-20 leaves and 4-5 cm and 5-7 leaves are cut, and they are classified for cutting. The cuttings with a length of 8-10 cm are cut from the middle and divided into two sections, with a sharp tip at the top and a blunt tip at the bottom. The cuttings are marked separately. After trimming, the cuttings retain 1-2 cm at the bottom and 4-5 leaves at the top, with an overall length of 4-5 cm. The cutting method and culture method are the same as those of the first generation cuttings. After survival, the culture method is the same as that of the first generation.

[0023] Furthermore, in step (8), the second generation cuttings are obtained from the first generation cuttings of jujube hangings, and thus their morphology after survival is similar to that of jujube hangings. The third generation cuttings are derived from the second generation jujube hangings, and their processing and culture methods are the same as those of the second generation cuttings. The culture method after survival is the same as that of the first generation.

[0024] Compared with related technologies, the method for year-round propagation of jujube tissue culture seedlings by cuttings and rapid seedling formation, flowering and fruiting provided by the present invention has the following beneficial effects:

[0025] The present invention utilizes unrooted jujube tissue culture seedlings for cuttings, rooting, transplanting, water and fertilizer management, temperature, light and humidity management, and application of exogenous growth regulators. This achieves rapid seedling formation after direct cutting and rooting of unrooted tissue culture seedlings, rapid year-round propagation, and flowering and fruiting. This solves the problems of low survival rate of jujube tissue culture seedlings after rooting, hardening, and transplanting, and late flowering of seedlings. It accelerates the propagation of large clone seedlings, obtains a large number of clone seedlings and rootstocks with stable and high-quality traits, and improves production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 Photos of the process of inoculating tissue culture seedlings into the culture medium provided in Example 1, 'jujube tissue culture seedlings' grown in the culture medium for 30 days, and 'jujube tissue culture seedlings' taken out of the culture medium and not trimmed for cuttings;

[0027] Figure 2 The photos of the tissue culture seedlings provided in Example 1 after pruning and ready for cutting, and the photos of the 'jujube tissue culture seedlings' after rooting;

[0028] Figure 3 The photos of the 'jujube tissue culture seedlings' provided in Example 1 grown in the cutting medium for 30 days and transplanted to the seedling medium;

[0029] Figure 4 This is a photo of the 'jujube tissue culture seedlings' provided in Example 1 when they grew to an average plant height of 15 cm in the transplanting medium;

[0030] Figure 5 The flowering photos of the 'jujube tissue culture seedlings' that were pinched 50 days after transplantation and the 'jujube tissue culture seedlings' that were not pinched 90 days after transplantation provided in Example 1;

[0031] Figure 6 This is a photo of the 'jujube tissue culture seedlings' obtained after topping treatment as provided in Example 1;

[0032] Figure 7 The photos of the second generation tissue culture seedlings provided in Example 1 were obtained by picking the jujubes from the jujube tissue culture seedlings with an average plant height of 15 cm and then leaving and pinching the tips;

[0033] Figure 8 The photos of the third generation tissue culture seedlings and cuttings provided for Example 1. DETAILED DESCRIPTION

[0034] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0035] Unless otherwise defined, technical or scientific terms used in the present invention shall have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs.

[0036] Example 1 A technology for year-round propagation of jujube tissue culture seedlings by cuttings and rapid seedling formation, flowering and fruiting, comprising the following steps:

[0037] 1. Culture medium for jujube tissue culture seedlings

[0038] (1) On February 29, 2024, various types of jujube tissue culture seedlings were inoculated into MS culture medium and cultured in the tissue culture room of the East Campus of Hebei Agricultural University at an ambient temperature of 22-25℃ and a light intensity of 3000lx for 45 days.

[0039] (2) On April 8, 2024, the jujube tissue culture seedlings in the culture medium were taken out, the proliferative parts at the bottom and the leaves were removed, and cuttings with an overall length of 4-5 cm were obtained. The cuttings were placed in a 1.25 g / L carbendazim solution and soaked for 5 minutes. The cuttings were taken out and dried or wiped dry. The base of the cuttings was soaked in a 1000 mg / LIBA solution for 10 seconds. After taking them out, they were inserted into a 32-hole plug tray that had been pre-filled with a cutting medium. The cutting medium had been disinfected with a 1.25 g / L carbendazim solution for 5-20 hours. After the cuttings were completed, they were watered thoroughly. The dripping water at the bottom of the plug tray was used as the standard for watering the medium thoroughly. Then, they were cultured in a light incubator. The environmental conditions were: daytime temperature: 30°C, nighttime temperature: 25°C, light intensity 6000 lx, and photoperiod 16h / 8h. The survival rate was 65.25%.

[0040] (3) When the above-mentioned tissue culture seedlings take root, the roots break through the plug tray, and the above-ground part begins to grow, the jujube tissue culture seedlings of basically the same size and strong growth are transplanted into a seedling pot with a diameter of 25 cm. The seedling medium is selected as the seedling culture medium: earthworm castings: peat: perlite = 3:2:1:1. Water and fertilizer are fully supplied. Spray 9.18 mg / LC CGMP every 7 days, water once every 10 days with 1000 times liquid starch-dissolving microbial fertilizer, and water once every 30 days with 0.88 g / L Hogland nutrient solution. Cultivate in an artificial climate control room with environmental conditions of 28 ° C during the day and 23 ° C at night, 6000 lx of light intensity, and 16h / 8h photoperiod. The tissue culture seedlings and cuttings began to grow rapidly 20 days after transplanting, and began to branch in large numbers 30 days after transplanting. The average height of the cuttings was 15 cm, the average stem diameter was 1.49 mm, the average length of the jujube branches was 5 cm, and the average number of secondary branches was 6. They were defined as first-generation tissue culture seedlings and cuttings. (50 days after transplanting) when the first generation of tissue culture seedlings and cuttings grew to an average height of 21 cm and an average stem diameter of 2.63 mm, they were topped and ring-cut to reduce the downward transport of nutrients and promote flower bud differentiation; (90 days after transplanting) when the first generation of tissue culture seedlings and cuttings (not topped and ring-cut) grew to an average plant height of 46 cm, an average stem diameter of 3.13 mm and an average length of jujube branches of 38.5 cm, flower buds began to appear on the cuttings. The tissue culture seedlings and cuttings treated with the above two types of treatments were sprayed with potassium dihydrogen phosphate solution on the leaves every 15 days, irrigated with 1000 times liquid starch-dissolving microbial fertilizer once every 10 days, and sprayed with 30 mg / L gibberellin solution once every 7 days to promote their extensive flowering and fruit setting.

[0041] (4) When the tissue culture seedlings grow to an average plant height of 15 cm and begin to branch, the second generation of jujube tissue culture seedlings can be cut. Select the jujube branches in the same position as the tissue culture seedlings. The average length of the jujube branches is 4-5 cm, and the number of leaves is 5-6. Prune the jujube branches. One type of jujube branches has the tip left, and the other type has the tip removed. Remove the lower 2-3 leaves of both types, and retain 4-5 leaves on the upper part of the 1-2 cm stem segment. Insert the cuttings into the cutting medium and place them in a light incubator for cultivation. The culture conditions are daytime temperature 32 ° C, nighttime temperature 25 ° C, and light intensity 100-150. The light intensity is 15000lx, and the photoperiod is 16h / 8h. On August 1, 2024 (30 days after the second-generation cuttings), the survival rate of the hanging jujubes was 100%, the average plant height growth of the aboveground part was 0.013cm, and the average growth of the aboveground stem diameter was 0mm. The survival rate of the jujube hangings after tip removal was 87.5%, the average plant height growth of the aboveground part was 0cm, and the average growth of the aboveground stem diameter was 0mm. The growth of the underground roots was the main process of survival of the cuttings. Rooting began 14 days after cutting, and the roots broke through the seedling pot 30 days after cutting.

[0042] (5) On September 14, 2024, the second-generation tissue culture seedlings were used for cuttings. 30 days later, the third-generation tissue culture seedlings were obtained, and the cutting survival rate was 100%.

[0043] (6) The second and third generation tissue culture seedlings are rapidly grown into large seedlings, and the culture conditions after transplanting are the same as those of the first generation.

[0044] 2. Cultivation Effect Identification

[0045] 1. Cutting survival rate assessment: To investigate the survival of tissue culture seedlings, the survival rates of the three generations of tissue culture seedlings in the above embodiment were observed and statistically analyzed, and the survival rates of the cuttings were calculated. The results are shown in Table 1.

[0046] Table 1 Statistics on the survival rate of cuttings of the third generation of cuttings

[0047]

[0048] 2. Identification of root growth of cuttings: In order to investigate the root growth of the third-generation tissue culture seedlings, the roots of the third-generation tissue culture seedlings in the above embodiment were observed and counted to obtain the root conditions of the third-generation tissue culture seedlings. The results are shown in Table 2.

[0049] Table 2 Investigation on root growth of third-generation tissue culture seedlings and cuttings

[0050]

[0051] 3. Identification of the rapid cultivation effect of large seedlings: In order to investigate the rapid seedling formation of the first-generation tissue culture seedlings and cuttings, the average values ​​of plant height, stem diameter, secondary branches, and jujube hanging length of the first-generation tissue culture seedlings at different stages in the above embodiment were statistically analyzed. At the same time, the plant height, stem diameter, and jujube hanging growth of the tissue culture seedlings at different stages were calculated. The results are shown in Tables 3 and 4.

[0052] Table 3 Investigation on plant height, stem diameter and secondary branch characteristics of first generation cutting seedlings

[0053]

[0054] Table 4 Survey on plant height, stem diameter and growth of first generation cutting seedlings

[0055]

[0056] 4. Identification of rapid flowering and fruiting traits of large seedlings: In order to investigate the rapid flowering of the first-generation tissue culture seedlings and cuttings, the earliest flowering time, average number of flowers, flowering node, fruiting node, plant height, stem diameter, and child length of the untopped and topped large seedlings in the above examples were statistically analyzed. The results are shown in Table 5.

[0057] Table 5. Investigation of flowering and fruiting characteristics of large seedlings

[0058]

[0059] The above results show that the present invention can enable jujube tissue culture seedlings to take root and grow directly in a plug tray containing a substrate without the rooting and seedling training process, avoiding a series of problems such as the difficulty of training and transplanting the tissue culture seedlings obtained under traditional tissue culture conditions, and achieving rapid and efficient seedling formation. The use of multiple types of jujube tissue culture seedlings improves the applicability of the present invention, and the present invention can enable jujube tissue culture seedlings to quickly grow into seedlings and bloom and bear fruit in the same year. This invention is of great significance for accelerating the jujube tree breeding process, and can quickly obtain a large number of asexual seedlings and trait-stable rootstocks.

[0060] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit the same. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solutions of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for year-round propagation of jujube tissue culture seedlings by cuttings and rapid seedling formation, flowering and fruiting, characterized in that: The steps include: Step 1: Place 1-2 cm tissue culture seedling stem segments in MS medium and culture for about 45 days until they are in a non-rooted state. When the tissue culture seedlings grow to 4-6 cm and have 6-8 leaves, select the non-rooted jujube tissue culture seedlings of uniform size and strong growth as cutting materials; Step 2, the jujube tissue culture seedlings are taken out from the culture medium, the callus tissue proliferating at the base of the tissue culture seedlings and the withered leaves at the bottom are removed, and the upper 3-5 leaves are retained. The length of the whole tissue culture seedling cuttings is 4-5 cm, with 3-5 leaves on the upper part and a 0.5 cm stem segment at the lower part; Step 3: Soak the treated tissue culture seedling cuttings in a 1.25 g / L carbendazim solution for 5 min, dip them in a 1000 mg / L IBA solution for 10 s, insert the lower end of the cuttings into the prepared cutting medium, and place them in a light incubator at 25-30°C, 95% humidity, and 6000 lx for rooting. Step 4: When the above-mentioned tissue culture seedlings take root, the root system breaks through the plug tray and the aboveground part begins to grow, the jujube tissue culture seedlings that are basically the same in size and grow vigorously are transplanted into a seedling pot with a diameter of 25CM, and the seedling medium: earthworm castings: peat: perlite = 3:2:1:1 is selected as the seedling culture medium. Water and fertilizer are fully supplied, 9.18mg / L CGMP is sprayed every 7d, 1000 times liquid starch-dissolving microbial fertilizer is applied once 10d, and 0.88g / L Hogland nutrient solution is applied once 30d; Step 5, the tissue culture seedling cuttings began to grow rapidly 20 days after transplanting, and began to branch in large numbers after 30 days. The average plant height of the cuttings was 15 cm, the average stem diameter was 1.49 mm, the average number of secondary branches was 3, and the hanging length was 4-5 cm. They were defined as first-generation tissue culture seedling cuttings; Step 6, when the first-generation tissue culture seedling cuttings that were not pinched grew to an average plant height of 46cm and an average stem thickness of 3.13mm, flower buds began to appear in the cuttings; the first-generation tissue culture seedling cuttings that were pinched grew to an average plant height of 21cm and an average stem thickness of 2.67mm, and flower buds began to appear in the cuttings. Potassium dihydrogen phosphate solution was sprayed on its leaf surface every 15d, 1000 times of liquid starch-dissolving microbial fertilizer was applied on 10d, and a gibberellin solution with a concentration of 30mg / L was sprayed on 7d to promote its large-scale flowering and fruit setting; Step 7: cutting the tender shoots from the first-generation tissue culture seedling cuttings as cuttings, and performing cuttings to obtain second-generation tissue culture seedling cuttings; Step 8: cutting off tender shoots from the second-generation tissue culture seedling cuttings as cuttings, and performing cuttings to obtain third-generation tissue culture seedling cuttings; After cutting the tender shoots of the jujube hanging from the first-generation tissue culture seedlings and the second-generation tissue culture seedlings, they can be cultured for 15-30 days according to step 4 of the tissue culture seedling cultivation method, and then the tender shoots of the jujube hanging can be cut again for cutting.

2. The method for annual propagation and rapid seedling formation, flowering and fruiting of jujube tissue culture seedlings according to claim 1, wherein: In the step 1, the jujube tissue culture seedlings are cultured in MS culture medium at an ambient temperature of 20° C., a humidity of 45%, and a light intensity of 3000 lx.

3. The method for annual propagation and rapid seedling formation, flowering and fruiting of jujube tissue culture seedlings according to claim 1, wherein: In step 2, the proliferative portion of the tissue culture seedlings grown in the MS medium for 45 days needs to be cut off before cutting.

4. The method for annual propagation and rapid seedling formation, flowering and fruiting of jujube tissue culture seedlings according to claim 1, wherein: In the step 3, the cutting substrate is peat: perlite = 3:1, and the cutting substrate needs to be disinfected with 1.25g / L carbendazim solution according to the weight of the substrate before use, substrate: carbendazim solution = 1100g:1L.

5. The method for year-round breeding and rapid seedling formation, flowering and fruiting of jujube tissue culture seedlings according to claim 1, wherein: In the step 3, the base of the cuttings needs to be reduced from breaking during the cutting process. After the cutting is completed, the cuttings are ensured to be perpendicular to the substrate, and lodging is reduced to improve the cutting survival rate and ensure the normal upward growth of the later transplanted cuttings.

6. The method for year-round breeding and rapid seedling formation, flowering and fruiting of jujube tissue culture seedlings according to claim 1, wherein: The transplanting of cuttings into large seedlings in steps 4 and 5 is carried out in an artificial climate control room, with environmental conditions of 25-30° C. during the day and 20-25° C. at night, a light intensity of 6000 lx, and a photoperiod of 16h / 8h.

7. The method for year-round breeding and rapid seedling formation, flowering and fruiting of jujube tissue culture seedlings according to claim 1, wherein: In the step 6, the jujube tissue culture seedlings are pinched to remove the terminal buds of the jujube seedlings; the pinched and unpinched tissue culture seedlings are moved into an artificial climate control room with an environmental condition of 23-25° C. during the day, 16-18° C. at night, a light intensity of 20,000 lx, and a photoperiod of 16h / 8h.

8. The method for year-round propagation and rapid seedling formation, flowering and fruiting of jujube tissue culture seedlings according to claim 1, wherein: In the step 7, strong and uniformly growing cuttings are selected from the first-generation tissue culture seedlings, and tender shoots of the cuttings are cut at the same position for cutting. The cuttings are 8-10 cm in length, 15-20 leaves, and 4-5 cm in length, 5-7 leaves. They are classified for cutting, and the cuttings with a length of 8-10 cm are cut from the middle and divided into two sections for cutting respectively, with no tip at the lower end and a tip at the upper end, and are marked respectively. After trimming, the lower end of the trimmed cuttings retains 1-2 cm, the upper end retains 4-5 leaves, and the overall length is 4-5 cm; the cutting method and the culture method are the same as those of the first-generation cuttings; and the culture method after survival is the same as that of the first generation.

9. The method for year-round propagation and rapid seedling formation, flowering and fruiting of jujube tissue culture seedlings according to claim 1, wherein: In step 8, the second generation cuttings are obtained from the first generation cuttings, so their morphology after survival is similar to that of the jujube hangings. The third generation cuttings are derived from the second generation jujube hangings, and their processing and cultivation methods are the same as those of the second generation cuttings; the cultivation method after survival is the same as that of the first generation.

Images