Method for rapidly breeding strawberry virus-free original seedlings and application thereof

Abstract

The invention relates to the technical field of fruit tree germplasm resource preservation and breeding, in particular to a method capable of rapidly breeding strawberry virus-free original seedlings all year round. According to the method provided by the invention, a sterilized plastic box (containing vermiculite) with air holes and a rooting nutrient solution are adopted, and the adaptability of transplanted seedlings to the environment is greatly improved through virus-free original seedling rooting induction, simple photoacclimatization and soil-carrying transplanting, so that the seasonal limitation in the test-tube plantlet transplanting process is eliminated, the transplanting time is shortened, and the survival rate of the test-tube plantlets is increased. And the transplanting survival rate is improved (more than 95%). According to the method provided by the invention, the breeding process of the secondary original seedlings is shortened and simplified as much as possible by improving the seedling cultivation technical means, the survival rate of the seedlings is improved, the method is not limited to specific seasons, virus-free original seedlings can be provided for strawberry production all the year round, and the method is suitable for large-scale production. The problems of high cost, complex links, mixed varieties, high variation probability and the like in the tissue culture process are greatly avoided.

Description

Technical Field

[0001] The invention relates to the technical field of fruit tree germplasm resource preservation and breeding, and in particular to a method for rapidly breeding virus-free strawberry original seedlings throughout the year. Background Art

[0002] Strawberry is a fruit with high nutritional value, wide adaptability, easy cultivation, and significant economic and social benefits. In strawberry production, with the extension of the cultivation period, the harm of virus diseases becomes more and more serious. Generally, the yield will drop significantly after 2 to 3 years of continuous planting, and the fruit will become smaller, the proportion of deformed fruits will increase, and the taste will gradually deteriorate. In addition, since strawberry seedlings are mostly propagated by runners in production, once the mother plant is infected with the virus, it will be directly transmitted to the offspring, causing serious variety degeneration, and even reduced production and income. For viral diseases, there are currently no special chemical agents available, and it cannot be solved by improving field management measures. Removing viruses and cultivating virus-free seedlings through biotechnology is a reasonable and effective method to ensure the advantages of excellent strawberry variety seedlings, maintain their resistance to stress and pests and diseases, reduce the occurrence of strawberry pests and diseases, and improve strawberry yield and quality.

[0003] At present, the production of virus-free strawberry seedlings is mainly a three-level breeding system, namely, primary seedling cultivation, secondary seedling expansion and tertiary production seedling breeding. In the existing breeding system, primary seedling cultivation is mainly achieved through biotechnology means such as stem tip culture detoxification technology, heat treatment plus stem tip culture detoxification technology and ultra-low temperature detoxification technology. Secondary seedling breeding requires the establishment of a more mature tissue culture technology system, especially subculture proliferation culture, rooting culture and seedling hardening and transplanting technologies. The breeding of tertiary production seedlings is mainly achieved by producers through field expansion. In actual production, the cultivation of primary and secondary seedlings is often completed by professional companies because it requires higher biotechnology means, and producers mainly breed production seedlings by purchasing virus-free seedlings. In this system, in addition to having higher professional technical means for virus removal and cultivation of virus-free seedlings, professional companies also need to invest a lot of manpower and financial resources to expand the secondary seedlings. In this process, with the increase in production capacity and the increase in varieties, phenomena such as variety mixing and variation also appeared, and this problem was exponentially amplified with the progress of tissue culture, which in turn caused huge losses in production and became a bottleneck hindering the development of the strawberry industry. In addition, although tissue culture technology is not restricted by seasons and has a high reproduction coefficient, the rooting and transplanting of secondary original seedlings has strict requirements on temperature, humidity and environment, and the reproduction time is short, which also has a great impact on the production capacity of virus-free seedlings.

[0004] In view of this, the present invention is proposed. Summary of the invention

[0005] In order to solve the above technical problems, the technical solutions provided by the present invention are as follows: In the first aspect, the present invention provides a method for rapidly breeding virus-free strawberry seedlings, which uses a sterilized plastic box with air holes (containing vermiculite) and rooting nutrient solution, and induces rooting of the virus-free seedlings, simple light acclimation and transplanting with soil, thereby improving the adaptability of the transplanted seedlings to the environment and getting rid of the seasonal restrictions in the process of transplanting test tube seedlings. The transplanted seedlings grow new leaves after 5 days, and the transplant survival rate is over 95%.

[0006] The method provided by the present invention improves the seedling cultivation technical means, has simple environmental requirements and is easy to operate, shortens and simplifies the breeding process of secondary original seedlings as much as possible, and avoids the problems of high cost, complex links, mixed varieties and high probability of mutation in the tissue culture process; and is not limited to a specific season, and can provide virus-free original seedlings for strawberry production all year round.

[0007] Preferably, the rooting nutrient solution formula includes: potassium nitrate 900±100 mg / L, ammonium nitrate 800±100 mg / L, calcium chloride 220±20 mg / L, magnesium sulfate 180±20 mg / L, potassium dihydrogen phosphate 85±10 mg / L, ferrous sulfate 27±3 mg / L, disodium ethylenediaminetetraacetic acid 37.3±5 mg / L, IBA 0.25±0.02 mg / L, and IAA 0.15±0.02 mg / L.

[0008] Preferably, a sterilizable plastic box with air holes is used. The size of the plastic box can be changed, but it is preferably not less than 10±1cm╳10±1cm╳8±1cm (length╳width╳height); the top of the plastic box has at least one air hole with an air permeable membrane, and the area of ​​each air hole is 3.14±1cm 2 The filtration pore size of the breathable membrane is 0.2±0.05µm.

[0009] Preferably, the bottom of the plastic box is paved with vermiculite, the height of the vermiculite is 2-3 cm, and the volume ratio of vermiculite to rooting nutrient solution is 1:0.5-0.6.

[0010] Preferably, healthy strawberry test tube seedlings with a height of not less than 2.5 cm are selected on a sterile operating table and inoculated into a sterilized plastic box.

[0011] Preferably, the rooting is induced for 20-40 days under weak light at room temperature without direct exposure to natural sunlight and with a light intensity not exceeding 4000 Lux.

[0012] Preferably, at room temperature under weak light without direct natural sunlight, the light intensity does not exceed 4000 Lux, and the bottle cap is opened for 3 days for acclimatization, with the bottle cap opened to one-third of the opening on the first day, opened to one-half on the second day, and completely opened on the third day.

[0013] Preferably, the rooted strawberry seedlings are transplanted with vermiculite into nutrient pots or field planting, shaded with a shade net for 1 week, sprayed with 500 times carbendazim once after transplanting, and watered once every two days for moisture retention.

[0014] In a second aspect, the present invention provides application of the method in strawberry virus-free seedling breeding.

[0015] The rapid breeding technology of strawberry virus-free stock seedlings provided by the present invention can enable the company to breed secondary stock seedlings while cultivating virus-free stock seedlings, and can provide secondary stock seedlings to producers all year round. The producers can arrange the production time and production quantity independently, realize self-breeding, self-cultivation and self-use of virus-free strawberry seedlings for production, ensure the purity of virus-free seedlings to the greatest extent, reduce the cost of producers purchasing commercial seedlings, and at the same time, due to the simplification of the virus-free seedling breeding procedure, reduce the company's production cost and operating risk to the greatest extent.

[0016] Beneficial effects: The present invention provides a method for rapidly breeding virus-free original seedlings of strawberries, using a sterilized plastic box with air holes (containing vermiculite) and a rooting nutrient solution, inducing rooting, simple light acclimation and transplanting with soil through virus-free original seedlings, improving the adaptability of transplanted seedlings to the environment, getting rid of the seasonal restrictions in the process of transplanting test tube seedlings, and growing new leaves after 5 days, with a transplant survival rate of more than 95%. The method provided by the present invention shortens and simplifies the breeding process of secondary original seedlings as much as possible through the improvement of seedling cultivation technology, greatly avoiding the problems of high cost, complex links, mixed varieties and high probability of variation in the process of tissue culture and rapid propagation; and is not limited to a specific season, and can provide virus-free original seedlings for strawberry production all year round. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the drawings required for use in the embodiments or the description of the prior art will be described below.

[0018] Figure 1 The healthy strawberry virus-free original seedling test tube individual plant that has been subcultured for 30 days and is used in Example 1 of the present invention.

[0019] Figure 2 This is a photo of the virus-free original seedlings transferred to a plastic box for culture in Example 1 of the present invention.

[0020] Figure 3 These are the rooted original seedlings obtained by culture in the plastic box in Example 1 of the present invention and the virus-free original seedlings of strawberry transplanted into the nutrient pots.

[0021] Figure 4 This is a photo of the virus-free original seedlings transferred to a plastic box for culture in Example 2 of the present invention.

[0022] Figure 5These are the rooted original seedlings obtained by culture in plastic boxes in Example 2 of the present invention and the virus-free original seedlings of strawberry transplanted to the field for management.

[0023] Figure 6 This is a photo of the virus-free rooted seedlings in Comparative Example 1 of the present invention being transplanted into nutrient pots in a plastic arch shed. DETAILED DESCRIPTION

[0024] In order to solve the problems of high technical requirements for cultivating secondary original seedlings, large cost investment, variety mixing and mutation probability in the process of breeding virus-free original seedlings of strawberry, high environmental requirements for rooting and transplanting and narrow transplanting time range, high seedling purchasing costs for producers and low autonomy in breeding production seedlings, the present invention provides a method for rapidly breeding virus-free original seedlings of strawberry throughout the year.

[0025] The method provided by the present invention can simultaneously and simply and quickly obtain rooted secondary original seedlings in the process of cultivating virus-free original seedlings, and transplanting and propagation are not restricted by seasons, the required technical requirements are low, and the requirements for environmental temperature and humidity during transplanting can be minimized. The method provided by the present invention is not only conducive to the rapid establishment of virus-free original seedlings of new strawberry varieties, but also can reduce the excessive demand for tissue culture technology for the expansion and propagation of secondary original seedlings, simplify the seedling breeding system, and can meet the needs of producers to independently breed virus-free production seedlings, which is of great significance to improving the social and economic benefits of the strawberry industry.

[0026] To achieve the above purpose, the technical solution of the present invention is as follows: The invention provides a method for rapidly breeding virus-free strawberry seedlings throughout the year, comprising: prior preparation (sterilized plastic boxes with air holes, vermiculite, sterilized rooting nutrient solution, sterilized water), selection of virus-free seedlings, washing of seedlings and transfer to plastic boxes, rooting induction, opening of covers for acclimatization and transplanting of seedlings.

[0027] Taking into account the high technical requirements for the expansion and propagation of strawberry secondary original seedlings, the existence of variety mixing and variation probability in the subculture process, the complicated transplanting process of tissue culture rooting secondary original seedlings and the high requirements for the environment and temperature and humidity, the present invention induces rooting under weak light by adopting a sterilized plastic box with air permeable holes and rooting nutrient solution induction, and the rooting original seedlings can be directly transplanted to the field or greenhouse after opening the cover and domestication, and provided to producers for autonomous rapid breeding of production seedlings. This method not only alleviates the problems of high tissue culture technical conditions, unstable purity and numerous influencing factors, but also allows producers to independently breed production seedlings at any convenient time by purchasing a small amount of rooting original seedlings. The solution provided by the present invention has simple production technical conditions, which not only reduces the investment and technical requirements for producing a large number of secondary original seedlings, but also avoids the variety mixing and variation probability in the process of tissue culture expansion and propagation of strawberry secondary original seedlings to the greatest extent, thereby reducing the operating risks of professional companies. At the same time, since this method is not restricted by seasons and can be supplied all year round, producers can reasonably arrange the seedling breeding progress and output, which not only reduces the producer's input but also ensures its production autonomy, achieving the goal of killing two birds with one stone.

[0028] As a preferred embodiment of the present invention, the method for rapidly breeding strawberry virus-free original seedlings throughout the year comprises the following steps: (1) Preparation: a) Sterilizable plastic box with ventilation holes (length╳width╳height: 26cm╳22cm╳15.5cm, with ventilation holes for adding breathable filter membrane; or length╳width╳height: 10cm╳10cm╳8cm, with ventilation holes for adding breathable filter membrane).

[0029] b) Spread the vermiculite on the bottom of the plastic box, about 2-3 cm thick, sterilize the plastic box at 121℃ for 15 minutes and set aside.

[0030] c) Nutrient solution: prepare rooting nutrient solution, comprising: 900 mg / L potassium nitrate, 800 mg / L ammonium nitrate, 220 mg / L calcium chloride, 180 mg / L magnesium sulfate, 85 mg / L potassium dihydrogen phosphate, 27 mg / L ferrous sulfate, 37.3 mg / L disodium ethylenediaminetetraacetic acid, 0.25 mg / L IBA, 0.15 mg / L IAA, dissolve in tap water, sterilize at 121°C for 15 min, and set aside.

[0031] d) Tap water, sterilize at 121℃ for 15 min, set aside.

[0032] (2) Selection of virus-free stock seedlings: On a sterile operating table, select healthy strawberry virus-free test tube seedlings that have been subcultured for 30 days, with a height of no less than 2.5 cm, separate individual plants as original seedlings, and the rest can be used for tissue culture rapid propagation.

[0033] (3) Washing and transfer of virus-free test tube seedlings: On a sterile operating table, gently wash the strawberry test tube seedlings in sterile water to remove the culture medium. Open the sterile plastic box, pour in the rooting nutrient solution, vermiculite: nutrient solution = 1:0.5-0.6 (V:V), insert the test tube seedlings into the vermiculite, and insert 15-20 plants (large box) or 4-6 plants (small box) into each plastic box.

[0034] (4) Root induction: Place the plastic box (containing rooting nutrient solution and test tube seedlings) in a weak light environment without direct natural light, with a light intensity of less than 4000 Lux, for weak light acclimatization and rooting induction, and the culture time is 20-40 days. The ambient temperature is sufficient.

[0035] (5) Opening the lid for acclimation: At room temperature without direct natural light, the light intensity does not exceed 4000 Lux. Open the cap for 3 days. Open the cap to one-third of the opening on the first day, open it to one-half on the second day, and open the cap completely on the third day.

[0036] (6) Transplanting of rooted seedlings: Transplant the rooted strawberry seedlings with vermiculite into nutrient pots or field planting, shade them with shade nets for 1 week, spray them with 500 times carbendazim once after transplanting, and spray water every two days to keep them moist.

[0037] The present invention also provides application of the above-mentioned method for rapidly breeding strawberry virus-free original seedlings throughout the year in breeding strawberry virus-free seedlings.

[0038] The method provided by the present invention uses a sterile plastic box, which can be reused. The processing method is simple, and only the first step must be performed in a sterile environment, and no special technical conditions are required for subsequent work. The environmental requirements are simple, and no temperature and humidity control is required. Only one spraying is required after transplanting. The transplanting process causes little damage, and the seedlings recover quickly in the later stage and have strong growth potential.

[0039] The method provided by the present invention can provide strawberry rooting original seedlings throughout the year without seasonal restrictions, and producers can arrange the purchase of seedlings earlier according to future production needs to reduce production input. Breeding companies can simultaneously breed rooting original seedlings in the process of cultivating virus-free original seedlings, eliminating the large tissue culture and rapid propagation investment, thereby using more energy for the detoxification of new strawberry varieties and the renewal of virus-free original seedlings. In addition, since the company can save a large amount of tissue culture and rapid propagation processes, the purity of the strawberry original seedlings is guaranteed, the probability of mutation is reduced to a minimum, and the company's operating risks are greatly reduced.

[0040] In summary, the method for rapidly breeding virus-free strawberry seedlings throughout the year provided by the present invention simplifies the strawberry virus-free seedling breeding procedure, reduces the dependence on tissue culture technology, avoids various risks in the tissue culture process to a great extent, ensures the purity and quality of the seedlings, and effectively reduces the excessive requirements on the environment and conditions, ensures the transplant survival rate of the strawberry seedlings, realizes the year-round supply of seedlings, is convenient for producers to independently master and arrange the production schedule, reduces the cost of production seedlings, achieves the purpose of benefiting both the company and the producer, and promotes the promotion and practical application of virus-free strawberry seedlings.

[0041] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be described clearly and completely below. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] The endpoints and any values ​​of the ranges disclosed in this specification are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0043] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "specific implementations", or "some specific implementations" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the embodiment of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0044] In the examples provided in this specification, if no specific techniques or conditions are specified, the techniques or conditions described in the literature in this field or the product instructions are used. If the manufacturer of the reagents or instruments used is not specified, they are all conventional products that can be purchased through regular channels.

[0045] Example 1

[0046] This embodiment provides a method for rapidly breeding virus-free strawberry seedlings throughout the year.

[0047] The method provided in this embodiment includes the following steps: (1) Preparation: a) Sterilizable plastic box with ventilation holes (length, width, height: 26 cm, width, height: 22 cm, height: 15.5 cm, with 8 ventilation holes for adding air permeable filter membranes, each with an area of ​​3.14 cm 2 , the filtration pore size of the air permeable filter membrane is 0.2µm).

[0048] b) Spread vermiculite (4±1mm) on the bottom of the plastic box, about 2-3 cm, sterilize the plastic box at 121℃ for 15 minutes and set aside.

[0049] c) Rooting nutrient solution, including: potassium nitrate 900 mg / L, ammonium nitrate 800 mg / L, calcium chloride 220 mg / L, magnesium sulfate 180 mg / L, potassium dihydrogen phosphate 85 mg / L, ferrous sulfate 27 mg / L, disodium EDTA 37.3 mg / L, IBA 0.25 mg / L, IAA 0.15 mg / L, dissolved in tap water, sterilized at 121°C for 15 min, and set aside.

[0050] d) Tap water, sterilize at 121℃ for 15 min, set aside.

[0051] (2) Selection of virus-free stock seedlings: On a sterile operating table, select healthy strawberry virus-free test tube seedlings ( Figure 1 ), separate single plants as virus-free original seedlings, with a height of not less than 2.5cm, and the rest can be used for rapid propagation.

[0052] (3) Washing and transfer of virus-free test tube seedlings: On a sterile operating table, wash the virus-free test tube seedlings with sterile water to remove the culture medium. Open the sterile plastic box and pour in the rooting nutrient solution. Vermiculite: nutrient solution = 1:0.5-0.6 (V:V), insert the virus-free test tube seedlings into the vermiculite, and insert 15-20 virus-free test tube seedlings into each plastic box ( Figure 2 ).

[0053] (4) Weak light culture and root induction: Place the plastic box (containing rooting nutrient solution and virus-free original seedlings) in a room temperature environment without direct natural light for weak light cultivation and root induction. The light intensity should not exceed 4000 Lux and the cultivation time should be 20-40 days.

[0054] (5) Opening the lid for acclimation: Under weak light without direct natural sunlight at room temperature, the light intensity does not exceed 4000Lux, and the bottles are opened for 3 days for acclimatization. On the first day, the bottle cap is opened to one-third of the opening, on the second day, it is opened to one-half, and on the third day, the bottle cap is completely opened.

[0055] (6) Transplanting of rooted seedlings: Transplant the rooted strawberry seedlings with vermiculite into the nutrient pots, shade them with shade nets for 1 week, spray them with 500 times carbendazim once after transplanting, and spray them with water every two days to keep them moist. Figure 3 ).

[0056] The virus-free strawberry seedlings bred in this embodiment have a rooting induction rate of more than 98%, a transplant survival rate of more than 95%, and a fast recovery speed of the seedlings during the transplanting process, growing new leaves 5 days after transplanting.

[0057] Example 2

[0058] This embodiment provides a method for rapidly breeding virus-free strawberry seedlings throughout the year.

[0059] The method provided in this embodiment includes the following steps: (1) Preparation: a) Sterilizable plastic box with ventilation holes (length, width, height: 10 cm, width, height: 10 cm, width, height: 8 cm, with a ventilation hole on the top of the lid for adding a breathable filter membrane, the ventilation hole area is 3.14 cm 2 , the filtration pore size of the air permeable filter membrane is 0.2µm).

[0060] b) Spread vermiculite (4±1mm) on the bottom of the plastic box, about 2-3 cm, sterilize the plastic box at 121℃ for 15 minutes and set aside.

[0061] c) The rooting nutrient solution contains: potassium nitrate 900 mg / L, ammonium nitrate 800 mg / L, calcium chloride 220 mg / L, magnesium sulfate 180 mg / L, potassium dihydrogen phosphate 85 mg / L, ferrous sulfate 27 mg / L, disodium EDTA 37.3 mg / L, IBA 0.25 mg / L, IAA 0.15 mg / L, dissolved in tap water, sterilized at 121°C for 15 min, and set aside.

[0062] d) Tap water, sterilize at 121℃ for 15 min, set aside.

[0063] (2) Selection of virus-free stock seedlings: On a sterile operating table, select healthy strawberry virus-free test tube seedlings that have been subcultured for 30 days, separate individual plants as virus-free original seedlings with a height of no less than 2.5 cm, and the rest can continue to be used for rapid propagation.

[0064] (3) Washing and transfer of virus-free test tube seedlings: On a sterile operating table, wash the virus-free test tube seedlings with sterile water to remove the culture medium. Open the sterile plastic box and pour in the rooting nutrient solution. Vermiculite: nutrient solution = 1:0.5-0.6 (V:V), insert the virus-free test tube seedlings into the vermiculite, and insert 4-6 virus-free test tube seedlings into each plastic box ( Figure 4 ).

[0065] (4) Weak light culture and root induction: Place the plastic box (containing rooting nutrient solution and virus-free original seedlings) in a room temperature environment without direct natural light for weak light cultivation and root induction. The light intensity should not exceed 4000 Lux and the cultivation time should be 20-40 days.

[0066] (5) Opening and acclimation: Under weak light without direct natural sunlight at room temperature, the light intensity does not exceed 4000Lux, and the bottles are opened for 3 days for acclimatization. On the first day, the bottle cap is opened to one-third of the opening, on the second day, it is opened to one-half, and on the third day, the bottle cap is completely opened.

[0067] (6) Transplanting of rooted seedlings: Transplant the rooted strawberry seedlings with vermiculite to the field, shade them with shade nets for 1 week, spray them with 500 times carbendazim once after transplanting, and spray them with water every two days to keep them moist. Figure 5 ).

[0068] The virus-free strawberry seedlings bred in this embodiment have a rooting induction rate of more than 98%. The rooted seedlings can be directly transplanted to a greenhouse or field for breeding production seedlings. The transplanting survival rate is more than 95%. The seedlings recover quickly during the transplanting process and are easy to manage. New leaves grow 5 days after transplanting.

[0069] Comparative Example 1

[0070] This comparative example provides a method for conventionally breeding virus-free strawberry seedlings.

[0071] The method provided in this comparative example comprises the following steps: (1) Preparation: a) Breeding calendar: Breeding of strawberry rooted test tube seedlings begins in early February each year. In mid-March, the rooted test tube seedlings are acclimated in the greenhouse. In early to mid-April, the rooted test tube seedlings are transplanted to nutrient pots. In mid-May, the nutrient pot seedlings are transferred to the field for breeding production seedlings.

[0072] b) Rooting medium: 1 / 2MS + 0.3mg / LIBA + 0.3mg / LIAA, sucrose 15g / L, agar powder 6.0g / L, pH 5.8), sterilize at 121℃ for 15min, set aside.

[0073] (2) Selection of virus-free stock seedlings: On a sterile operating table, select healthy strawberry virus-free test tube seedlings that have been subcultured for 30 days and separate individual plants with a height of no less than 2.5 cm.

[0074] (3) Rooting induction of virus-free test tube seedlings: On a sterile operating table, insert virus-free test tube seedlings into root induction medium, 3-4 plants per culture bottle, at 25±2℃, light intensity 2000Lux, photoperiod 16 hours light / 8 hours dark, induce rooting, and the induction time is 20-40 days.

[0075] (3) Acclimation and cultivation of rooted test tube seedlings: The rooted test tube seedlings were transferred to the greenhouse and first light-acclimated under shade conditions for 10 days, then the shade nets were gradually removed and acclimated under natural light for 7 days.

[0076] (4) Opening the lid for acclimation: Open the lid and acclimate in the greenhouse for 3 days. Open the lid to one-third of the first day, open it to one-half on the second day, and open the lid completely on the third day.

[0077] (5) Preparation before transplanting: Prepare nutrient soil, fine soil: vermiculite = 2:1, and sterilize under high pressure.

[0078] Prepare a plastic arch shed with a shade net.

[0079] (6) Transplanting of rooted seedlings: Take out the strawberry rooting test tube seedlings, wash them with clean water 2-3 times, wash off the root culture medium, transplant the test tube seedlings into the nutrient pots, and then transfer them to the plastic arch shed ( Figure 6 ), spray 500 times of carbendazim and provide shade with shade net.

[0080] (7) Management after transplanting rooted seedlings: The rooted seedlings were cultured in the plastic arch for 3 weeks, during which time they were sprayed with carbendazim once every 7 days, and the humidity was controlled at 80-90%. After 1 week, the soil was gradually ventilated, new leaves grew after 2 weeks, and the plastic arch was gradually removed after 3 weeks. After 1 month, the shade net was removed and the seedlings could be transplanted to the field for breeding.

[0081] This comparative example is a conventional method for breeding strawberry virus-free original seedlings. It can be seen that compared with the method of the present invention, the conventional breeding method is restricted by season, and the steps are cumbersome, there are many influencing factors, the time required is more than 2 months, and the management during the transplanting process requires high professional technical experience.

[0082] 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 it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for rapidly breeding virus-free strawberry seedlings, characterized in that: By using a sterilized plastic box with air holes and containing vermiculite and a rooting nutrient solution, the adaptability of transplanted seedlings to the environment is improved through inducing rooting of virus-free original seedlings, simple light acclimation and transplanting with soil.

2. The method for rapidly breeding virus-free strawberry seedlings according to claim 1, characterized in that: The rooting nutrient solution formula includes: potassium nitrate 900±100mg / L, ammonium nitrate 800±100mg / L, calcium chloride 220±20mg / L, magnesium sulfate 180±20mg / L, potassium dihydrogen phosphate 85±10mg / L, ferrous sulfate 27±3mg / L, disodium ethylenediaminetetraacetic acid 37.3±5mg / L, IBA0.25±0.02mg / L, and IAA 0.15±0.02mg / L.

3. The method for rapidly breeding virus-free strawberry seedlings according to claim 1, characterized in that: The length, width and height of the plastic box should not be less than 10±1cm╳10±1cm╳8±1cm; the top of the plastic box should have at least one air hole, and the area of ​​each air hole should be 3.14±1cm 2 The filtration pore size of the breathable membrane is 0.2±0.05µm.

4. The method for rapidly breeding virus-free strawberry seedlings according to claim 1, characterized in that: Vermiculite is spread flat on the bottom of the plastic box with a height of 2-3cm; the volume ratio of vermiculite to rooting nutrient solution is 1:0.5-0.

6.

5. The method for rapidly breeding virus-free strawberry seedlings according to claim 1, characterized in that: On a sterile operating table, select healthy strawberry test tube seedlings with a height of no less than 2.5 cm and inoculate them into a sterilized plastic box.

6. The method for rapidly breeding virus-free strawberry seedlings according to claim 1, characterized in that: Under weak light without direct natural sunlight at room temperature, the light intensity does not exceed 4000Lux, and the rooting time is 20-40 days.

7. The method for rapidly breeding virus-free strawberry seedlings according to claim 1, characterized in that: Under weak light without direct natural sunlight at room temperature, the light intensity does not exceed 4000Lux, and the bottles are opened for 3 days for acclimatization. On the first day, the bottle cap is opened to one-third of the opening, on the second day, it is opened to one-half, and on the third day, the bottle cap is completely opened.

8. The method for rapidly breeding virus-free strawberry seedlings according to claim 1, characterized in that: Transplant the rooted strawberry seedlings with vermiculite into nutrient pots or field planting, shade them with shade nets for 1 week, spray them with 500 times carbendazim once after transplanting, and spray water every two days to keep them moist.

9. Application of the method according to any one of claims 1 to 8 in virus-free strawberry seedling breeding; the method gets rid of the seasonal restrictions in the process of transplanting test tube seedlings, new leaves grow after 5 days of transplanting, and the transplant survival rate is over 95%.

Images