A method for germinating and seedling-forming blueberry hybrid seeds

Abstract

The present application provides a method for germination and seedling formation of blueberry hybrid seeds, wherein the obtained fresh blueberry hybrid seeds are placed in an incubator for variable temperature cultivation; when the height of the seedlings is 3-5 cm, they are transplanted to a greenhouse for cultivation, and when the height of the seedlings is 20-25 cm, they are transplanted to an open-air cultivation; 2-3 main upright branches are cultivated; fruiting branches are increased; and finally, an evaluation is performed. Fresh blueberry seeds are directly sown in nutrient matrix soil, and the seeds do not need to be air-dried or refrigerated. The steps are simple and the operation is convenient. They can germinate in about 15 days, shortening the time by 3-6 months, and the germination rate can reach more than 95%. After one year of planting, the single plant material can be evaluated and screened for fruiting, which greatly shortens the breeding cycle, reduces operating costs, and speeds up the breeding process, as the existing technology requires 4-5 years before fruiting and evaluation.

Description

Technical Field

[0001] The present application belongs to the technical field of fruit tree cultivation, and more specifically, to a method for germination and seedling formation of blueberry hybrid seeds. Background Art

[0002] Blueberry breeding in my country started late and the breeding process was slow. In addition to the lack of excellent breeding plants, the limiting factors of blueberry hybrid breeding are the low germination rate of blueberry seeds after hybridization, which makes it impossible to select seeds effectively. This is because blueberry seeds have the characteristics of winter dormancy, and the seeds are small in size and not easy to germinate; some slightly larger seeds cannot germinate due to thick seed coats, and some seeds cannot form complete embryos. The existing technology appropriately improves the germination rate of blueberry seeds and shortens the germination time through seed soaking, low temperature induction, gibberellin pretreatment and other technologies. The above steps are cumbersome, and the effect of gibberellin treatment is unstable. Different blueberry varieties have different concentrations of gibberellin treatment, and the treatment differences are also very large; the existing technology is that after the blueberry hybrid seeds are seedled, they grow slowly and have a long juvenile period. It takes 4-5 years to evaluate the yield and fresh fruit quality. The breeding cycle is long, time-consuming and labor-intensive, and the operating cost is high. Summary of the invention

[0003] The technical problem to be solved by the present invention is: how to shorten the breeding cycle of blueberries while simplifying the breeding steps and improving the germination rate. The present invention provides a method for germination and seedling formation of blueberry hybrid seeds, which mainly adopts variable temperature cultivation, thereby improving the germination rate and shortening the breeding cycle.

[0004] The technical solution of the present invention is: a method for germination and seedling formation of blueberry hybrid seeds, comprising:

[0005] The obtained fresh blueberry hybrid seeds are placed in an incubator for variable temperature culture. Before the seeds germinate, the culture temperature during the day is 18-22°C, the light intensity is 900-1200lx, and the culture time is 10-13 hours; the dark culture is adopted at night, the culture temperature is 8-12°C, the culture time is 7-9 hours, the culture temperature is 4-6°C, the culture time is 2-7 hours, and the air humidity is 80-87%;

[0006] After the seeds germinate, the culture temperature is 24-26°C, the light intensity is 900-1200lx, and the culture time is 10-13 hours during the day; dark culture is adopted at night, the culture temperature is 24-26°C, the culture time is 11-14 hours, and the air humidity is 80-87%;

[0007] When the height of the seedlings is 3-5 cm, they are transplanted to a greenhouse for cultivation with an air humidity of 65%-75% and a cultivation temperature of 24-26°C.

[0008] When the height of the seedlings is 20-25 cm, they are transplanted to open-air cultivation; the open-air cultivation process includes the vegetative growth period, the flowering period and the fruiting period, the mass ratio in the vegetative growth period is N:P:K=1:1:1, the mass ratio in the flowering period is N:P:K=2:1:2, the mass ratio in the fruiting period is N:P:K=2:1:4, and the soil moisture is 65%-85%;

[0009] Remove weak and drooping branches, cultivate 2-3 main upright branches; shorten the main branches to promote lateral branches and increase fruiting branches;

[0010] The plant type, plant height, branching and resistance of individual plants are investigated; in the second year, the fruit size and quality of individual fruit-bearing plants are measured and evaluated, and plants that meet the requirements are selected.

[0011] As a possible implementation mode, before the seeds germinate, the daytime culture time is 12 hours, specifically 6:00-18:00; for night culture, the culture temperature is 8-12°C, the culture time is 8 hours, specifically 18:00-2:00, and the culture temperature is 4-6°C, the culture time is 4 hours, specifically 2:00-6:00.

[0012] As a possible implementation manner, the blueberry hybrid seeds are obtained by hybridizing Legacy and Emerald, or by hybridizing Legacy and Skylark (FL 01-173).

[0013] As a possible implementation mode, the nutrient matrix used in the culture in the incubator and the greenhouse is a mixture of peat soil and perlite in a mass ratio of 7:3.

[0014] As a possible implementation mode, the nutrient soil used in open-air cultivation is a mixture of peat soil, coconut bran and perlite in a mass ratio of 4:3:3.

[0015] As a possible implementation method, before the seeds germinate, the culture temperature during the day is 20°C, the light intensity is 1000lx, and the culture time is 12 hours; dark culture is adopted at night, the culture temperature is 10°C, the culture time is 8 hours, the culture temperature is 5°C, the culture time is 4 hours, and the air humidity is 85%.

[0016] As a possible implementation method, after the seeds germinate, the culture temperature is 25°C, the light intensity is 1000lx, and the culture time is 12 hours during the day; dark culture is adopted at night, the culture temperature is 25°C, the culture time is 12 hours, and the air humidity is 80-87%.

[0017] As a possible implementation mode, the plants are cultured outdoors and a nutrient solution is applied every 5 to 8 days. The nutrient solution is prepared from acidic monomer fertilizer and has a pH value of 5.0 to 5.5 and an electrical conductivity of 0.5 to 0.8 ms / cm.

[0018] As a possible implementation mode, the blueberry hybrid seeds are cultured in an incubator, and the thickness of the nutrient matrix soil covering the surface of the blueberry hybrid seeds is 0.4 to 0.6 cm.

[0019] As a possible implementation method, the nutrient matrix soil involved in the culture box and greenhouse culture needs to be disinfected.

[0020] The beneficial effects of the present invention are:

[0021] 1. The present invention directly sows fresh blueberry seeds in the nutrient matrix soil. The seeds do not need to be air-dried or refrigerated, nor do they need to be pre-treated by mechanical damage, low-temperature induction, or chemical reagent soaking. The steps are simple and easy to operate. The peat soil in the nutrient matrix soil can provide all the nutrients required for the seedlings, and the perlite drainage and ventilation provide favorable conditions for the growth of the seedling root system. At the same time, the germination time can be shortened and the germination rate can be increased through variable temperature cultivation. Compared with the prior art, the germination can be completed in about 15 days, the time is shortened by 3-6 months, and the germination rate can reach more than 95%.

[0022] 2. The present invention uses different nutrient media to transplant and cultivate seedlings, and uses nutrient solutions with different ratios for water and fertilizer management at different growth stages. At the same time, it uses scientific pruning techniques to cultivate tree shape and promote flower bud differentiation. Individual plants can be evaluated and screened after one year of planting, which is different from the prior art that requires 4-5 years for fruit evaluation and screening. This greatly shortens the breeding cycle, reduces operating costs, and speeds up the breeding process. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0024] Figure 1 This is a diagram of the early germination stage of blueberry hybrid seeds in Example 1;

[0025] Figure 2 This is a schematic diagram of transplanting during the greenhouse planting period in Example 1;

[0026] Figure 3 A single growth diagram for the open-air planting period in Example 1;

[0027] Figure 4It is a group growth diagram during the open-air planting period in Example 1;

[0028] Figure 5 This is a schematic diagram of the fruit bearing state of a single plant in Example 1;

[0029] Figure 6 This is a schematic diagram of the fruit-bearing state of another single plant in Example 1. DETAILED DESCRIPTION

[0030] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0031] At present, the varieties of blueberries planted in my country mainly rely on imports. The limiting factor of blueberry hybrid breeding is the low germination rate of blueberry seeds after hybridization, which makes it impossible to carry out effective seed selection. The germination methods currently used for hybrid seeds mainly include seed soaking, low temperature induction, gibberellin pretreatment and other technologies. These technologies can appropriately increase the germination rate of blueberry seeds and shorten the germination time, but these technologies have one thing in common: the steps are relatively cumbersome, resulting in unstable germination effects, and the breeding time takes 4-5 years. Therefore, there are problems such as long breeding cycle, time-consuming and labor-intensive, and high operating costs. Among them, the effect of gibberellin pretreatment is the most unstable, which is specifically manifested in: different blueberry varieties have different concentrations of gibberellin treatment, and the treatment differences are also very large.

[0032] In view of the above problems, the present invention provides a method for germination and seedling formation of blueberry hybrid seeds, comprising the following steps:

[0033] S1. The obtained fresh blueberry hybrid seeds are placed in an incubator for variable temperature culture. Before the seeds germinate, the culture temperature during the day is 18-22°C, the light intensity is 900-1200lx, and the culture time is 10-13 hours; the dark culture is adopted at night, the culture temperature is 8-12°C, the culture time is 7-9 hours, the culture temperature is 4-6°C, the culture time is 2-7 hours, and the air humidity is 80-87%;

[0034] In this step, "fresh blueberry hybrid seeds" refer to seeds directly obtained from blueberry fruits and not air-dried, which can be obtained by the following methods:

[0035] Crush the ripe blueberry hybrid fruit with a handheld juicer, then rinse and precipitate it repeatedly with clean water. Remove the pulp and immature seeds floating on the water surface, and use filter paper to absorb the water of the ripe seeds at the bottom for later use.

[0036] The incubator is a constant temperature and light incubator, in which blueberry hybrid seeds are placed in a plug tray. Before sowing blueberry hybrid seeds, a composite nutrient matrix needs to be added to the plug tray. The composite nutrient matrix is ​​a mixture of peat soil and perlite in a mass ratio of 7:3. After the seeds are sown, a layer of composite nutrient matrix needs to be covered on the surface of the seeds. The thickness of the composite nutrient matrix is ​​generally about 0.50 cm, for example, 0.4 to 0.6 cm. The number of seeds sown in each hole is generally 10 to 15.

[0037] A preferential cultivation method before seed germination is: the daytime cultivation temperature is 20°C, the light intensity is 1000lx, and the cultivation time is 12 hours; the night is dark cultivation, the cultivation temperature is 10°C, the cultivation time is 8 hours, the cultivation temperature is 5°C, the cultivation time is 4 hours, and the air humidity is 85%; specifically, the start and end times of daytime and dark cultivation are 6:00-18:00, 18:00-2:00, and 2:00-6:00, respectively.

[0038] The fresh blueberry hybrid seeds involved in this step can be obtained by crossing Legacy and Emerald, or Legacy and Meadowlark (FL 01-173 (Meadowlark TM )) hybridization, the specific hybridization breeding is as follows:

[0039] 1. Collect pollen: The two varieties of 'Emerald' and 'Skylark' are early-maturing varieties, and they bloom about 15 days earlier than 'Lagesi'. Pollen needs to be collected in advance. Collect the flowers of these two varieties with their petals just opening in a sulfuric acid paper bag and bring them back to the laboratory. Then remove the petals with tweezers, put the stamens in a clean culture dish and place it in a light incubator at 25℃ with a light intensity of 2000lx for 24 hours to make the anthers split and collect pollen. After collecting the pollen, seal the edge of the culture dish with sealing glue and store it in a refrigerator at 4℃ for later use.

[0040] 2. Emasculation: Remove the stamens when the buds (before the petals bloom) form at the beginning of the flowering period of 'Legesi'. Select the thicker and 10cm-15cm long fruiting branches from the robust plants as the experimental objects. First, use tweezers to remove the opened flowers on the top of the fruiting branches and the too small inflorescences below, leaving 4-5 buds on each inflorescence; then use tweezers to remove the petals and stamens of the remaining buds, leaving the pistils. And put a sulfuric acid paper bag on the fruiting branches, and pin the bottom with a paper clip to prevent other pollen from mixing in.

[0041] 3. Pollination: After 10 am, open the sulfuric acid paper bag, dip the brush in pollen and touch the stigma of the emasculated flower, touch back and forth 2-3 times; after pollination, put on the sulfuric acid paper bag again and fix it with a paper clip to avoid mixing with other pollen. Write a label to indicate the female and male plants.

[0042] 4. Collecting fruits: When the hybrid fruits are fully mature (the color of the fruits turns into blue or dark blue), cut off the entire fruiting branch and bring it back to the laboratory. Pick the fruits according to different hybrid combinations and mark them for later use.

[0043] 5. Obtain hybrid seeds: Use a handheld juicer to crush the mature hybrid fruit, then rinse and precipitate it repeatedly with clean water. Remove the pulp and immature seeds floating on the water surface, and use filter paper to absorb the water on the surface of the mature seeds at the bottom for later use.

[0044] S2. After the seeds germinate, the culture temperature is 24-26°C during the day, the light intensity is 900-1200lx, and the culture time is 10-13 hours; dark culture is used at night, the culture temperature is 24-26°C, the culture time is 11-14 hours, and the air humidity is 80-87%;

[0045] A preferred cultivation method is: the cultivation temperature during the day is 25°C, the light intensity is 1000lx, and the cultivation time is 12 hours; dark cultivation is adopted at night, the cultivation temperature is 25°C, the cultivation time is 12 hours, and the air humidity is 85%; specifically, the start and end times of daytime and dark cultivation are 6:00-20:00 and 20:00-6:00 respectively.

[0046] S3. When the height of the seedlings is 3-5 cm, transplant them to a greenhouse for cultivation, with an air humidity of 65%-75% and a cultivation temperature of 24-26°C;

[0047] The culture medium used for greenhouse cultivation is a mixture of peat soil and perlite in a mass ratio of 7:3. It is mainly transplanted into seedling cups for cultivation. The temperature in the greenhouse is optimally controlled at 25°C.

[0048] S4. When the height of the seedlings is 20-25 cm, they are transplanted to open-air cultivation. The nutrient matrix used for open-air cultivation is a mixture of peat soil, coconut bran and perlite in a mass ratio of 4:3:3. The process is mainly potted. The open-air cultivation process includes a vegetative growth period, a flowering period and a fruiting period. The mass ratio during the vegetative growth period is N:P:K=1:1:1, the mass ratio during the flowering period is N:P:K=2:1:2, and the mass ratio during the fruiting period is N:P:K=2:1:4. The soil moisture is 65% to 85%;

[0049] In this step, it is also necessary to irrigate the nutrient solution at a frequency of about one week. The nutrient solution is mainly acidic monomer fertilizer, such as ammonium sulfate, potassium dihydrogen phosphate, magnesium sulfate, calcium nitrate, and a combination of at least two kinds, wherein the amount of each substance is weighed according to the mass ratio of N:P:K=1:1:1 in the vegetative growth period, the mass ratio of N:P:K=2:1:2 in the flowering period, and the mass ratio of N:P:K=2:1:4 in the fruiting period. The pH value of the nutrient solution is generally 5.0-5.5, and the electrical conductivity (EC) value is 0.5-0.8ms / cm.

[0050] S5. Remove weak and drooping branches, cultivate 2-3 main upright branches; shorten the main branches, promote side branches, and increase fruiting branches;

[0051] S6. Investigate the plant type, plant height, branching and resistance of individual plants; in the second year, measure and evaluate the fruit size and quality of individual fruit-bearing plants, and select plants that meet the requirements.

[0052] 1. The present invention directly sows fresh blueberry seeds in the nutrient matrix soil. The seeds do not need to be air-dried or refrigerated, nor do they need to be pre-treated by mechanical damage, low-temperature induction, or chemical reagent soaking. The steps are simple and easy to operate. The peat soil in the nutrient matrix soil can provide all the nutrients required for the seedlings, and the perlite drainage and ventilation provide favorable conditions for the growth of the seedling root system. At the same time, the germination time can be shortened and the germination rate can be increased through variable temperature cultivation. Compared with the prior art, the seeds can germinate in about 15 days, the time is shortened by 3 to 6 months, and the germination rate can reach more than 95%.

[0053] 2. The present invention uses different nutrient media to transplant and cultivate seedlings, and uses nutrient solutions with different ratios for water and fertilizer management at different growth stages. At the same time, it uses scientific pruning techniques to cultivate tree shape and promote flower bud differentiation. Individual plants can be evaluated and screened after one year of planting, which is different from the prior art that requires 4-5 years for fruit evaluation and screening. This greatly shortens the breeding cycle, reduces operating costs, and speeds up the breeding process.

[0054] Example 1

[0055] In this experiment, hybrid seeds of 'Legacy×Emerald' were used as test plants. On June 21, 2021, the mature hybrid fruits were harvested and brought back to the laboratory, crushed with a handheld juicer, and then rinsed and precipitated repeatedly with clean water. The pulp and immature seeds floating on the water surface were removed, and the mature seeds at the bottom were dried with filter paper to set aside. The obtained seeds were divided into 3 portions, each with 100 seeds, and treated with the method of the present invention, low temperature induction, and 0.2% gibberellin soaking, respectively, and repeated 3 times. The specific experimental process and results are as follows:

[0056] 1. Experimental process and results of the method of the present invention

[0057] (1) On June 21, 2021, the cleaned hybrid seeds were directly sown in a plug tray containing a sterilized peat soil: perlite (mass ratio of 7:3) composite nutrient matrix, covered with 0.50 cm of nutrient matrix soil, watered thoroughly to keep moisture, and placed in a constant temperature and light incubator for cultivation. The conditions of the constant temperature and light incubator are: the culture conditions are 20°C during the day, 1000lx of light, 12 hours; dark culture at 10°C for 8 hours, 5°C for 4 hours at night, and air humidity of 85%.

[0058] (2) After 13 to 15 days, the seeds begin to germinate and emerge from the culture medium. Figure 1 As shown, the seeds germinated and stretched out their cotyledons on the 16th to 18th day, the germination was uniform, and the germination rate reached 96%; after the seeds germinated, the conditions of the light incubator were set as follows: temperature 25°C, air humidity 85%, daytime light 1000lx, 14 hours, and dark culture at night for 10 hours.

[0059] (3) When the seedlings grow to 3-5 cm, they are transplanted into a seedling cup filled with a composite nutrient matrix of peat soil and perlite (mass ratio is 7:3) and placed in an ordinary greenhouse for cultivation. The air humidity is maintained at 65%-75%. The transplant survival rate is 98%. Figure 2 As shown,.

[0060] (4) In February 2022, the seedlings were transplanted into 3-gallon pots filled with a composite nutrient matrix of peat soil, coconut bran, and perlite (mass ratio of 4:3:3) for outdoor cultivation. Figure 3 and 4 shown.

[0061] (5) Water and fertilizer management: Water the plants once every 7 days during the growth period (mass ratio of N:P:K=1:1:1), flowering period (mass ratio of N:P:K=2:1:2), and fruiting period (mass ratio of N:P:K=2:1:4), and apply medium and trace elements together. Maintain soil moisture at 65% to 85%.

[0062] (6) Pruning: Remove weak and drooping branches, and cultivate 2 to 3 main upright branches; shorten the main branches to promote lateral branches and increase the number of fruiting branches.

[0063] (7) Evaluation: After a growth cycle, if Figure 5 and 6As shown in the figure, the plant type, plant height, branching and resistance of individual plants are investigated, and the phenological period is recorded; in May 2023, the fruit size and quality of individual plants with fruit are measured and evaluated, and plants with large fruits, good quality and good resistance are selected, among which the proportion of individual plants with fruit bearing is 96%, and all of them can be preliminarily screened to eliminate poor individual plants.

[0064] 2. Low temperature induction test process and results (comparative example)

[0065] (1) On June 21, 2021, the washed hybrid seeds were dried in the shade indoors, placed in a 4°C refrigerator for 48 hours, and then sown in a plug tray containing a sterilized peat soil: perlite (mass ratio of 7:3) composite nutrient matrix, covered with 0.50 cm of nutrient matrix soil, and watered to keep moisture, and placed in a constant temperature and light incubator for cultivation. The conditions of the constant temperature and light incubator are: temperature 20°C, air humidity 85%, daytime light 1000lx, 12 hours, and dark cultivation for 12 hours at night.

[0066] (2) After 6 months, the seeds gradually germinated, with a germination rate of 43%. After the seeds germinated, the conditions of the light incubator were set as follows: temperature 25°C, air humidity 85%, daytime light 1000lx, 14 hours, and dark incubation at night for 10 hours.

[0067] (3) When the seedlings grow to 3-5 cm, they are transplanted into seedling cups filled with a composite nutrient matrix of peat soil and perlite (mass ratio of 7:3) and placed in an ordinary greenhouse for cultivation. The air humidity is maintained at 65%-75%. The transplant survival rate is 86%.

[0068] (4) In May 2022, the seedlings were transplanted into 3-gallon pots filled with a composite nutrient matrix of peat soil, coconut coir and perlite (mass ratio of 4:3:3) for outdoor planting.

[0069] (5) Water and fertilizer management: Water the plants once every 7 days during the growth period (mass ratio of N:P:K=1:1:1), flowering period (mass ratio of N:P:K=2:1:2), and fruiting period (mass ratio of N:P:K=2:1:4), and apply medium and trace elements together. Maintain soil moisture at 65% to 85%.

[0070] (6) Pruning: Remove weak and drooping branches, and cultivate 2 to 3 main upright branches; shorten the main branches to promote lateral branches and increase the number of fruiting branches.

[0071] (7) Evaluation: After one growth cycle of observation, the plant type, plant height, branching and resistance of individual plants are investigated, and the phenological period is recorded; in May 2023, the fruit size and quality of a small number of fruit-bearing plants are measured and evaluated, and superior individual plants are screened, of which fruit-bearing plants account for 37%. Most plants need another year of growth before they can be evaluated.

[0072] 3. 0.2wt% gibberellin seed soaking induction test process and results (comparative example)

[0073] (1) On June 21, 2021, the washed hybrid seeds were dried in the shade indoors, soaked in 0.2wt% gibberellin at room temperature for 24 hours, and then sown in a plug tray containing a sterilized peat soil: perlite (mass ratio of 7:3) composite nutrient matrix, covered with 0.50 cm of nutrient matrix soil, and watered to keep moisture, and placed in a constant temperature and light incubator for cultivation. The conditions of the constant temperature and light incubator are: temperature 20°C, air humidity 85%, daytime light 1000lx, 12 hours, and dark cultivation for 12 hours at night.

[0074] (2) After 5 months, the seeds gradually germinated, with a germination rate of 56%. After the seeds germinated, the conditions of the light incubator were set as follows: temperature 25°C, air humidity 85%, daytime light 1000lx, 14 hours, and dark incubation for 10 hours at night.

[0075] (3) When the seedlings grow to 3-5 cm, they are transplanted into seedling cups filled with a composite nutrient matrix of peat soil and perlite (mass ratio of 7:3) and placed in an ordinary greenhouse for cultivation. The air humidity is maintained at 65%-75%. The transplant survival rate is 92%.

[0076] (4) In May 2022, the seedlings were transplanted into 3-gallon pots filled with a composite nutrient matrix of peat soil, coconut coir and perlite (mass ratio of 4:3:3) for outdoor planting.

[0077] (5) Water and fertilizer management: Water the plant with nutrient solution once every 7 days, during the growth period (mass ratio of N:P:K=1:1:1), flowering period (mass ratio of N:P:K=2:1:2), and fruiting period (mass ratio of N:P:K=2:1:4), and apply medium and trace elements together. Maintain soil moisture at 65%-85%.

[0078] (6) Pruning: Remove weak and drooping branches, and cultivate 2 to 3 main upright branches; shorten the main branches to promote lateral branches and increase the number of fruiting branches.

[0079] (7) Evaluation: After one growth cycle of observation, the plant type, plant height, branching and resistance of individual plants are investigated, and the phenological period is recorded; in May 2023, the fruit size and quality of a small number of fruit-bearing plants are measured and evaluated, and superior individual plants are screened, of which fruit-bearing plants account for 43%. Most plants need another year of growth before they can be evaluated.

[0080] Example 2

[0081] This experiment used 'Legacy'×'Skylark' [Legacy×FL 01-173 (Meadowlark TM )】The hybrid seeds were used as test plants. On June 21, 2021, the mature hybrid fruits were harvested and brought back to the laboratory, crushed with a handheld juicer, and then rinsed and precipitated repeatedly with clean water. The pulp and immature seeds floating on the water surface were removed, and the mature seeds at the bottom were dried with filter paper to set aside. The obtained seeds were divided into 3 portions, each with 100 seeds, and treated with the method of the present invention, low temperature induction, and 0.2% gibberellin soaking, respectively, and repeated 3 times. The specific experimental process and results are as follows:

[0082] 4. Experimental process and results of the method of the present invention

[0083] (1) On June 21, 2021, the cleaned hybrid seeds were directly sown in a plug tray containing a sterilized peat soil: perlite (7:3) composite nutrient matrix, covered with 0.50 cm of nutrient matrix soil, watered thoroughly to keep moisture, and placed in a constant temperature and light incubator for cultivation. The conditions of the constant temperature and light incubator are: the culture conditions are 20°C during the day, 1000lx of light, 12 hours; dark culture at 10°C for 8 hours, 5°C for 4 hours at night, and air humidity of 85%.

[0084] (2) After 10 to 12 days, the seeds began to germinate and emerge from the culture matrix. The seeds germinated and stretched out the cotyledons on the 14th to 16th day. The germination was uniform and the germination rate reached 94%. After the seeds germinated, the conditions of the light incubator were set as follows: temperature 25°C, air humidity 85%, daytime light 1000lx, 14 hours, and dark culture for 10 hours at night.

[0085] (3) When the seedlings grow to 3-5 cm, they are transplanted into seedling cups filled with a composite nutrient matrix of peat soil and perlite (mass ratio of 7:3) and placed in an ordinary greenhouse for cultivation. The air humidity is maintained at 65%-75%. The transplant survival rate is 98%.

[0086] (4) In February 2022, the seedlings were transplanted into 3-gallon pots filled with a composite nutrient matrix of peat soil, coconut coir and perlite (mass ratio of 4:3:3) for outdoor cultivation.

[0087] (5) Water and fertilizer management: Water the plant with nutrient solution once every 7 days, during the growth period (mass ratio of N:P:K=1:1:1), flowering period (mass ratio of N:P:K=2:1:2), and fruiting period (mass ratio of N:P:K=2:1:4), and apply medium and trace elements together. Maintain soil moisture at 65%-85%.

[0088] (6) Pruning: Remove weak and drooping branches, and cultivate 2 to 3 main upright branches; shorten the main branches to promote lateral branches and increase the number of fruiting branches.

[0089] (7) Evaluation: After one growth cycle of observation, the plant type, plant height, branching and resistance of individual plants are investigated, and the phenological period is recorded; in May 2023, the fruit size and quality of individual fruit-bearing plants are measured and evaluated, and plants with large fruits, good quality and good resistance are selected. Among them, the proportion of fruit-bearing plants is 98%, and all of them can be preliminarily screened to eliminate poor individual plants.

[0090] 5. Low temperature induction test process and results

[0091] (1) On June 21, 2021, the washed hybrid seeds were dried in the shade indoors, placed in a 4°C refrigerator for 48 hours, and then sown in a plug tray containing a sterilized peat soil: perlite (mass ratio of 7:3) composite nutrient matrix, covered with 0.50 cm of nutrient matrix soil, and watered to keep moisture, and placed in a constant temperature and light incubator for cultivation. The conditions of the constant temperature and light incubator are: temperature 20°C, air humidity 85%, daytime light 1000lx, 12 hours, and dark cultivation for 12 hours at night.

[0092] (2) After 6 months, the seeds gradually germinated, with a germination rate of 38%. After the seeds germinated, the conditions of the light incubator were set as follows: temperature 25°C, air humidity 85%, daytime light 1000lx, 14 hours, and dark incubation for 10 hours at night.

[0093] (3) When the seedlings grow to 3-5 cm, they are transplanted into seedling cups filled with a composite nutrient matrix of peat soil and perlite (mass ratio of 7:3) and placed in an ordinary greenhouse for cultivation. The air humidity is maintained at 65%-75%. The transplant survival rate is 88%.

[0094] (4) In May 2022, the seedlings were transplanted into 3-gallon pots filled with a composite nutrient matrix of peat soil, coconut coir and perlite (mass ratio of 4:3:3) for outdoor planting.

[0095] (5) Water and fertilizer management: Water the plants once every 7 days during the growth period (mass ratio of N:P:K=1:1:1), flowering period (mass ratio of N:P:K=2:1:2), and fruiting period (mass ratio of N:P:K=2:1:4), and apply medium and trace elements together. Maintain soil moisture at 65% to 85%.

[0096] (6) Pruning: Remove weak and drooping branches, and cultivate 2 to 3 main upright branches; shorten the main branches to promote lateral branches and increase the number of fruiting branches.

[0097] (7) Evaluation: After one growth cycle of observation, the plant type, plant height, branching and resistance of individual plants are investigated, and the phenological period is recorded; in May 2023, the fruit size and quality of a small number of fruit-bearing plants are measured and evaluated, and superior individual plants are screened, of which fruit-bearing plants account for 34%. Most plants need another year of growth before they can be evaluated.

[0098] 6. Process and results of the seed soaking induction test with 0.2wt% gibberellin

[0099] (1) On June 21, 2021, the washed hybrid seeds were dried in the shade indoors, soaked in 0.2wt% gibberellin at room temperature for 24 hours, and then sown in a plug tray containing a sterilized peat soil: perlite (mass ratio of 7:3) composite nutrient matrix, covered with 0.50 cm of nutrient matrix soil, and watered to keep moisture, and placed in a constant temperature and light incubator for cultivation. The conditions of the constant temperature and light incubator are: temperature 20°C, air humidity 85%, daytime light 1000lx, 12 hours, and dark cultivation for 12 hours at night.

[0100] (2) After 5 months, the seeds gradually germinated, with a germination rate of 52%. After the seeds germinated, the conditions of the light incubator were set as follows: temperature 25°C, air humidity 85%, daytime light 1000lx, 14 hours, and dark incubation for 10 hours at night.

[0101] (3) When the seedlings grow to 3-5 cm, they are transplanted into seedling cups filled with a composite nutrient matrix of peat soil and perlite (mass ratio of 7:3) and placed in an ordinary greenhouse for cultivation. The air humidity is maintained at 65% to 75%. The transplant survival rate is 93%.

[0102] (4) In May 2022, the seedlings were transplanted into 3-gallon pots filled with a composite nutrient matrix of peat soil, coconut coir and perlite (mass ratio of 4:3:3) for outdoor planting.

[0103] (5) Water and fertilizer management: Water the plant with nutrient solution once every 7 days, during the growth period (mass ratio of N:P:K=1:1:1), flowering period (mass ratio of N:P:K=2:1:2), and fruiting period (vN:P:K=2:1:4), and apply medium and trace elements together. Maintain soil moisture at 65% to 85%.

[0104] (6) Pruning: Remove weak and drooping branches, and cultivate 2 to 3 main upright branches; shorten the main branches to promote lateral branches and increase the number of fruiting branches.

[0105] (7) Evaluation: After one growth cycle of observation, the plant type, plant height, branching and resistance of individual plants are investigated, and the phenological period is recorded; in May 2023, the fruit size and quality of a small number of fruit-bearing plants are measured and evaluated, and superior individual plants are screened, of which fruit-bearing plants account for 41%. Most plants need another year of growth before they can be evaluated.

[0106] It can be seen from the above embodiments that the use of the variable temperature culture disclosed in the present invention and direct breeding with fresh seeds can not only shorten the germination time, but also significantly improve the germination rate and simplify the operating steps, and can also shorten the time for the plants to bear fruit, thereby shortening the breeding time. Specifically, individual plants can be evaluated and screened for fruiting one year after planting, which is different from the prior art that requires 4-5 years for fruiting evaluation and screening. This greatly shortens the breeding cycle, reduces operating costs, and speeds up the breeding process.

[0107] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for germination and seedling formation of blueberry hybrid seeds, characterized in that: The method comprises: The obtained fresh blueberry hybrid seeds are placed in an incubator for variable temperature culture. Before the seeds germinate, the culture temperature during the day is 18-22° C., the light intensity is 900-1200 lx, and the culture time is 12 hours, specifically 6:00-18:00; the culture temperature at night is 8-12° C., the culture time is 8 hours, specifically 18:00-2:00, the culture temperature is 4-6° C., the culture time is 4 hours, specifically 2:00-6:00, and the air humidity is 80-87%; After the seeds germinate, the culture temperature is 24-26°C, the light intensity is 900-1200lx, and the culture time is 10-13 hours during the day; dark culture is adopted at night, the culture temperature is 24-26°C, the culture time is 11-14 hours, and the air humidity is 80-87%; When the height of the seedlings is 3-5 cm, they are transplanted to a greenhouse for cultivation with an air humidity of 65%-75% and a cultivation temperature of 24-26°C. When the height of the seedlings is 20-25 cm, they are transplanted to open-air cultivation; the open-air cultivation process includes the vegetative growth period, flowering period and fruiting period; In this step, it is also necessary to water the nutrient solution once a week. The nutrient solution is prepared from at least two of ammonium sulfate, potassium dihydrogen phosphate, magnesium sulfate, and calcium nitrate. The amount of each substance is weighed according to the mass ratio of N:P:K=1:1:1 in the vegetative growth period, the mass ratio of N:P:K=2:1:2 in the flowering period, and the mass ratio of N:P:K=2:1:4 in the fruiting period. The soil moisture is 65% to 85%; Remove weak and drooping branches, cultivate 2-3 main upright branches; shorten the main branches to promote lateral branches and increase fruiting branches; Investigate the plant type, plant height, branching and resistance of individual plants; in the second year, measure and evaluate the fruit size and quality of individual fruit-bearing plants, and select plants that meet the requirements; The blueberry hybrid seeds are obtained by hybridizing Legacy and Emerald, or by hybridizing Legacy and Skylark (FL01-173); The nutrient matrix used in the incubator and greenhouse culture was a mixture of peat soil and perlite in a mass ratio of 7:3; The nutrient soil used in open-air cultivation is a mixture of peat soil, coconut coir and perlite in a mass ratio of 4:3:

3.

2. The method for germination and seedling formation of blueberry hybrid seeds according to claim 1, characterized in that: Before seed germination, the culture temperature during the day was 20°C, the light intensity was 1000lx, and the culture time was 12 hours; dark culture was adopted at night, the culture temperature was 10°C, the culture time was 8 hours, the culture temperature was 5°C, the culture time was 4 hours, and the air humidity was 85%.

3. The method for germination and seedling formation of blueberry hybrid seeds according to claim 1 or 2, characterized in that: After the seeds germinate, the culture temperature is 25°C, the light intensity is 1000lx, and the culture time is 12 hours during the day; dark culture is adopted at night, the culture temperature is 25°C, the culture time is 12 hours, and the air humidity is 80-87%.

4. The method for germination and seedling formation of blueberry hybrid seeds according to claim 1, characterized in that: The pH value of the nutrient solution applied in open-air cultivation is 5.0-5.5, and the conductivity is 0.5-0.8 ms / cm.

5. The method for germination and seedling formation of blueberry hybrid seeds according to claim 1, characterized in that: The blueberry hybrid seeds were cultured in an incubator, and the thickness of the nutrient matrix soil covering the surface of the blueberry hybrid seeds was 0.4 to 0.6 cm.

6. The method for germination and seedling formation of blueberry hybrid seeds according to claim 1, characterized in that: The nutrient matrix soil involved in incubator and greenhouse cultivation needs to be disinfected.

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