Method for regulating vernalization of celery and inducing bolting and flowering and application thereof

Abstract

The invention belongs to the technical field of cultivation and breeding, and particularly relates to a method for regulating vernalization of celery and inducing bolting and flowering, which comprises the following steps: selecting celery seedlings with 4-6 true leaves, and performing vernalization treatment to obtain celery plants; the vernalization treatment is light-dark alternate culture; the duration and temperature conditions are limited; after vernalization treatment, performing bolting and flowering induction on the celery plants; the bolting and flowering induction is light-dark alternate culture; and the duration and temperature conditions are limited. According to the method, the temperature and sunshine duration parameters are accurately regulated and controlled, so that the artificial controllable induction of bolting and flowering processes of different celery varieties is realized, the variety adaptation limitation in the prior art is thoroughly solved, the breeding period of the celery varieties is effectively shortened, and technical support is provided for rapid breeding of good celery varieties.

Description

Technical Field

[0001] This invention belongs to the field of cultivation and breeding technology, specifically relating to a method for regulating vernalization and inducing bolting and flowering in celery, and its application. Background Technology

[0002] celery( Apium graveolens Celery (Pheretima aspergillum), belonging to the genus Celery in the family Apiaceae, is an important vegetable crop widely cultivated globally. Rich in nutrients and with a unique flavor, it holds a significant place in consumers' daily diets. In the production and breeding of celery, bolting and flowering are crucial stages in its life cycle completion and variety propagation, directly impacting celery seed production efficiency, the progress of superior variety selection, and the development of related basic research.

[0003] In traditional celery cultivation, the bolting and flowering process relies heavily on natural environmental conditions and is greatly influenced by factors such as season, region, and climate. Under natural conditions, celery needs to undergo vernalization during winter's low temperatures (usually below 10℃) before bolting and flowering can begin under the induction of long days and high temperatures in spring. This entire process is lengthy, spans multiple years, and has poor controllability. In the breeding of superior varieties, under natural conditions, celery often requires a multi-year growth cycle from seedling to bolting, flowering, and seed setting. This long breeding cycle results in slow generational succession, severely restricting the selection and aggregation efficiency of superior traits in celery. In basic research on the growth and development mechanisms of celery, experimental conditions are difficult to standardize, making it impossible to obtain stable and controllable experimental materials. This affects the accuracy and reproducibility of research results and hinders in-depth exploration of key scientific issues such as the vernalization mechanism and flower development in celery. Even when artificially inducing bolting and flowering in celery through environmental control, the specific growth conditions are not clearly defined, and the celery variety type is not differentiated, limiting the applicability of this method. Therefore, there is an urgent need to develop a method for inducing bolting and flowering of celery that allows for precise parameter quantification, variety-specific adaptation, and coverage of multiple scenarios. Summary of the Invention

[0004] The purpose of this invention is to provide a method for inducing bolting and flowering in celery through vernalization and its application, which realizes full artificial control over the bolting and flowering process, avoids the influence of uncertainties in the natural environment, and effectively shortens the breeding cycle of celery varieties.

[0005] This invention provides a method for inducing bolting and flowering in celery through vernalization, comprising the following steps: Celery seedlings with 4-6 true leaves were selected and subjected to vernalization treatment to obtain celery plants. The vernalization treatment was a light-dark alternating culture. The daily light duration and darkness duration of the light-dark alternating culture were 11-13 hours and 11-13 hours respectively. The temperature during the light period was 6-9℃ and the temperature during the darkness period was 2-5℃. After the vernalization treatment, the celery plants are subjected to a bolting and flowering induction; the bolting and flowering induction is a light and dark alternating culture; the light and dark alternating culture has a light duration of 15-17 hours and a dark duration of 7-9 hours per day; during the bolting and flowering induction, the temperature during the light duration is 22-25 DEG C, and the temperature during the dark duration is 18-21 DEG C.

[0006] As a preferred solution, during the vernalization treatment, the light intensity is 100-200 µmol·m -2 ·s -1 ; during the bolting and flowering induction, the light intensity is 300-400 µmol·m -2 ·s -1 ; and the light source comprises a white light lamp.

[0007] As a preferred solution, the celery variety comprises a hollow celery variety and / or a solid celery variety.

[0008] As a preferred solution, the vernalization treatment duration of the hollow celery variety is 45-60 days; and the vernalization treatment duration of the solid celery variety is not less than 90 days. The hollow celery variety comprises at least one of the following: white celery, red celery and yellow heart celery.

[0009] As a preferred solution, the solid celery variety comprises at least one of the following: Ventura, Shen Qian No. 3 and Yu Yuan Queen.

[0010] As a preferred solution, before the vernalization treatment, a robust seedling fertilizer is applied once.

[0011] As a preferred solution, during the bolting and flowering induction, a high-phosphorus fertilizer is applied every 7-10 days; and the application mode of the high-phosphorus fertilizer comprises foliar spraying and root irrigation.

[0012] As a preferred solution, the vernalization treatment or the bolting and flowering induction is implemented in at least one of the following scenarios: artificial climate box cultivation, greenhouse cultivation and greenhouse cultivation.

[0013] The application provides an application of the above-mentioned method for regulating bolting and flowering induction of celery vernalization in rapid breeding of a fine celery variety.

[0014] As a preferred solution, the rapid breeding comprises the following steps: during hybrid pollination, using a hollow celery variety as a male parent and a solid celery variety as a female parent, continuously pollinating 3-5 times, and obtaining F1 hybrid seeds after breeding.

[0015] Beneficial effects: the application provides a method for regulating springing induction of celery to bloom, comprising the following steps: selecting 4-6 true leaf celery seedlings, performing springing treatment to obtain celery plants; the springing treatment is light and dark alternating culture; the light and dark alternating culture is 11-13h of light and 11-13h of darkness per day; during the springing treatment, the temperature during light is 6-9℃, and the temperature during darkness is 2-5℃; after the springing treatment, the celery plants are induced to bloom; the bloom induction is light and dark alternating culture; the light and dark alternating culture is 15-17h of light and 7-9h of darkness per day; during the bloom induction, the temperature during light is 22-25℃, and the temperature during darkness is 18-21℃. The application realizes artificial controllable induction of the bloom process of different celery varieties by precisely regulating the temperature and the length of sunshine, completely solves the variety adaptation limitation in the prior art, effectively shortens the breeding cycle of celery varieties, and provides technical support for rapid breeding of excellent celery varieties. The results of the examples show that after 7-15d of bloom induction culture, the celery plants can form bloom stems with obvious morphological characteristics, and after 25-35d of culture, the celery plants can bloom normally.

[0016] The application provides application of the above-mentioned method for regulating springing induction of celery to bloom in rapid breeding of excellent celery varieties. The celery plants obtained by the method have consistent growth states and controllable physiological processes, i.e., through "solid celery sowing 30-60d earlier + synchronous springing", the coincidence degree of the flowering period is ensured to be greater than 90%, and the method provides standardized materials for the basic research on the flower development of different celery varieties. The method for regulating springing induction of celery to bloom based on the temperature and the length of sunshine can realize "one-year two-season breeding" of celery. The period from 4-6 true leaf seedlings to flowering of hollow celery is 70-95d, and the corresponding period of solid celery is 115-155d, so the method has the advantages of simple operation, wide applicability and high industrialization promotion value, and has important significance for accelerating the breeding process of excellent celery varieties and promoting the basic research on the growth and development mechanism of celery. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 The phenotypic diagrams of white celery, yellow heart celery and red celery in different periods and under different treatments are shown in the drawings; wherein, A is white celery, yellow heart celery and red celery in the seedling stage; B is white celery, yellow heart celery and red celery after 60d of springing treatment; C is white celery, yellow heart celery and red celery after 25d of bloom induction treatment; Figure 2Figure 1 is a phenotypic diagram of three solid celery varieties, Shenqin No. 3, Yuyuan Queen and Ventura, under different periods and treatments; wherein, A is the seedling stage; B is the plant under vernalization treatment for 120 days; C is the whole plant under vernalization treatment for 120 days and bolting and flowering induction treatment for 25 days; Figure 3 Figure 2 is a phenotypic diagram of hollow celery variety white celery and solid celery Yuyuan Queen; wherein, A is the fertile line white celery inflorescence and floret which can be pollinated; B is the Yuyuan Queen inflorescence and floret which can receive foreign pollen; C is the fruit which expands and begins to change color 30 days after pollination; D is the phenotype of the fertile line white celery 15 days after seed germination; E is the phenotype of hybrid seeds 15 days after germination; Figure 4 Figure 3 is the bolting and flowering of Yuyuan Queen after vernalization and greenhouse cultivation and hybrid application; wherein, A is Yuyuan Queen after vernalization; B is the whole plant 25 days after planting; C is the whole plant 20 days after pollination; D is the expanded fruit 20 days after pollination. DETAILED DESCRIPTION

[0018] The application provides a method for regulating bolting and flowering of celery induced by vernalization, comprising the following steps: 4-6 true leaf celery seedlings are selected for vernalization treatment to obtain celery plants; the vernalization treatment is light and dark alternating culture; the light and dark alternating culture is 11-13 hours of light and 11-13 hours of darkness per day; during the vernalization treatment, the temperature during light is 6-9℃ and the temperature during darkness is 2-5℃; After the vernalization treatment, the celery plants are subjected to bolting and flowering induction; the bolting and flowering induction is light and dark alternating culture; the light and dark alternating culture is 15-17 hours of light and 7-9 hours of darkness per day; during the bolting and flowering induction, the temperature during light is 22-25℃ and the temperature during darkness is 18-21℃.

[0019] As a preferred embodiment, the variety of the celery in the application comprises: hollow celery variety and / or solid celery variety; the hollow celery variety comprises at least one of the following: white celery, red celery and yellow heart celery; the solid celery variety comprises at least one of the following: Ventura, Shensin No. 3 and Yuyuan Queen.

[0020] 4-6 true leaf celery seedlings are selected as the treatment object. As an optional embodiment, the celery seedlings are selected to be healthy and free of pests and diseases. The number of true leaves of the celery seedlings according to the present application can be any value in the range of 4-6, for example 4, 5 or 6; this period is the key period when the celery seedlings are in a stable physiological state and sensitive to vernalization, and using seedlings at this period as the treatment object can ensure the efficiency and stability of subsequent vernalization treatment and bolting induction. The height of the celery seedlings according to the present application can be any value in the range of 8-10 cm, for example 8, 9 or 10 cm. As an optional embodiment, the celery seedlings are managed daily. During the period of the celery seedlings according to the present application, light and dark alternating culture is preferably used; the light duration of the light and dark alternating culture is any value in the range of 11-13 h, for example 11, 12 or 13 h; the dark duration is any value in the range of 11-13 h, for example 11, 12 or 13 h. As an optional embodiment, the temperature during light is any value in the range of 22-25℃, for example 22, 23, 24 or 25℃, and the temperature during darkness is any value in the range of 18-21℃, for example 18, 19, 20 or 21℃. The strong seedling fertilizer is applied once before the vernalization treatment according to the present application; specifically, the fertilizer is applied one month after the celery seedlings emerge. The strong seedling fertilizer according to the present application is not particularly limited, and a conventional product can be used.

[0021] The selected celery seedlings are subjected to vernalization treatment to obtain celery plants. The vernalization treatment according to the present application is light and dark alternating culture; the light duration of the light and dark alternating culture is any value in the range of 11-13 h, for example 11, 12 or 13 h; the dark duration is any value in the range of 11-13 h, for example 11, 12 or 13 h. By precisely regulating the temperature and light parameters of the environment, the celery is induced to complete the vernalization process. During the vernalization treatment according to the present application, the light intensity can be any value in the range of 100-200 μmol·m -2 ·s -1 , for example 100, 150 or 200 μmol·m -2 ·s -1; the light intensity is "low light intensity", which is consistent with the natural light intensity in winter (from December to February of next year). As a preferred embodiment, the source of the light includes a white light lamp, such as a white LED lamp. During the vernalization process, the temperature during the light period is any value in the range of 6-9℃, such as 6, 7, 8, or 9℃; during the vernalization process, the temperature during the dark period is any value in the range of 2-5℃, such as 2, 3, 4, or 5℃; this temperature difference design can simulate the diurnal temperature variation in natural winter. As a preferred embodiment, the purification scenario includes at least one of the following: artificial climate chamber cultivation, greenhouse cultivation, and greenhouse cultivation; preferably using an artificial climate incubator. As a preferred embodiment, the vernalization duration of the hollow celery variety according to the present application can be any value in the range of 45-60d, such as 45, 50, 55, or 60d; hollow celery varieties have high vernalization sensitivity, and 45-60d can meet the critical vernalization requirement. As another preferred embodiment, the vernalization duration of the solid celery variety according to the present application is not less than 90d, and some varieties that are resistant to bolting may require a longer time. As a preferred embodiment, the seedling substrate is kept moist during the vernalization process, and no fertilizer is applied.

[0022] After vernalization, the celery plants are subjected to bolting and flowering induction. The bolting and flowering induction according to the present application is light-dark alternating culture; the light-dark alternating culture has a light period of any value in the range of 15-17h, such as 15, 16, or 17h; and a dark period of any value in the range of 7-9h, such as 7, 8, or 9h; 16h long-day light is a key photoperiod signal for celery bolting and flowering. During the bolting and flowering induction according to the present application, the temperature during the light period is any value in the range of 22-25℃, such as 22, 23, 24, or 25℃, and the temperature during the dark period is any value in the range of 18-21℃, such as 18, 19, 20, or 21℃; this temperature range is the most suitable temperature for celery flower bud differentiation. During the bolting and flowering induction according to the present application, the light intensity can be any value in the range of 300-400μmol·m -2 ·s -1 , such as 300, 350, or 400μmol·m -2 ·s -1The condition is more consistent with the condition of celery bolting and flowering in April to June in the natural environment. As an optional embodiment, the source of the light includes a white light lamp, such as a white light LED lamp. As an optional embodiment, the bolting and flowering induction scenario includes at least one of the following: artificial climate chamber cultivation, greenhouse cultivation and greenhouse cultivation. In specific embodiments, when greenhouse cultivation is selected, a region or season with a stable temperature of 20-35 DEG C is selected, for example, April to May in spring or September to October in autumn. Water and fertilizer management: high phosphorus fertilizer is applied every 7-10 days, and a combination of "foliar spraying + root irrigation" is used, and the old leaves at the bottom of the plant are removed in time (4-6 functional leaves are reserved per plant) to avoid blocking light and affecting the growth of flower stems. The bolting and flowering induction of the application can be applied every 7-10 days; for example, 7, 8, 9 or 10 days. The application of high phosphorus fertilizer is preferably a combination of foliar spraying and root irrigation. As an optional embodiment, the old leaves at the bottom of the plant are removed in time, 4-6 functional leaves are reserved per plant, and the light is prevented from being blocked to affect the growth of the flower stem. The application does not have special restrictions on the high phosphorus fertilizer, and a conventional product can be used. After 7-15 days of bolting and flowering induction culture, the plant forms an obvious bolting main stem, which is clearly distinguished from the petiole, and the top can see the flower primordium; after 25-35 days of bolting and flowering induction culture, the umbel inflorescence is completely formed, and then the small flowers are in bud, and enter the full flowering period.

[0023] The application provides the application of the above-mentioned method for regulating the vernalization-induced bolting and flowering of celery in the rapid breeding of excellent celery varieties. The celery plants obtained by the method have consistent growth states and controllable physiological processes, that is, by "solid celery early sowing by 30-45 days + synchronous vernalization", the coincidence degree of the flowering period is ensured to be > 90%; and the method provides standardized materials for the basic research of flower development of different celery varieties. As an optional embodiment, the rapid breeding includes the following steps: when hybrid pollination is performed, an empty celery variety is used as the father and a solid celery variety is used as the mother, and continuous pollination is performed 3-5 times, and after breeding, F1 generation hybrid seeds are obtained. In specific embodiments, "white celery" (empty celery) and Yu Garden Queen (solid celery) are selected as hybrid parents to realize the coincidence of the flowering periods of the two. Specifically, the solid celery (Yu Garden Queen) is sowed and grown 40 days earlier to ensure that it can be synchronized with the vernalization process of the subsequent sowing of the empty celery after entering the vernalization treatment; the empty celery (white celery) is sowed and grown after the solid celery is sowed for 40-60 days to ensure that the solid celery enters the vernalization treatment while the empty celery is still in the seedling stage, and the solid celery completes the previous growth at the time when the empty celery reaches four true leaves, and synchronously enters the vernalization treatment. After the flowering periods of the empty celery and the solid celery are accurately met by the method, the hybrid pollination can be successfully completed, and high-quality hybrid seeds with a germination rate of 95% can be stably obtained, which fully meets the requirements of celery hybrid breeding on seed quality.

[0024] To further illustrate the present invention, the following detailed description, in conjunction with embodiments, of a method for regulating vernalization and inducing bolting and flowering in celery, and its application, should not be construed as limiting the scope of protection of the present invention.

[0025] Example 1: Comparison of vernalization and bolting of three hollow celery varieties 1. Seedling planting and seedling age selection Seedlings of white celery, yellow celery, and red celery were planted in a light-controlled incubator under the following conditions: a 14-hour light cycle and a 10-hour dark cycle; a temperature of 22°C during the light period and 18°C ​​during the dark period. During the cultivation period, all plants underwent routine water and fertilizer management, pest and disease control, and were given a single application of a high-element water-soluble fertilizer (such as Huawuque brand) as a seedling-strengthening fertilizer. When the seedlings reached a height of 8-10 cm and had 4 true leaves, experimental materials were selected strictly according to the following criteria: uniform growth, no obvious pest or disease symptoms, robust stems, and intact, dark green leaves. Finally, 30 seedlings meeting the above criteria were selected from each of the three celery varieties (one seedling from each variety was selected). Figure 1 (A), used as the test material for subsequent tests.

[0026] 2. Low-temperature vernalization treatment The selected seedlings were placed in an artificial climate incubator for low-temperature vernalization treatment. The culture environment was as follows: 8℃ during the light period, 4℃ during the dark period, 12h light / 12h dark, and a light intensity of 200 μmol·m⁻¹. -2 ·s -1 The light source was a white LED lamp. Plants were obtained after 60 days of low-temperature vernalization treatment (one plant of each variety was selected). Figure 1 (For seedlings in section B), keep the seedling substrate moist during the period, but do not apply fertilizer.

[0027] 3. Bolting and flowering induction After 60 days of low-temperature vernalization treatment, the plants were transferred to a light-controlled incubator for bolting and flowering induction. The incubation conditions were set as follows: 16h photoperiod / 8h darkperiod, 22℃ during the photoperiod and 18℃ during the darkperiod, and 400 μmol·m² light intensity. -2 ·s -1 The light source is a white LED lamp. During the induction period, apply Huawuque brand high-phosphorus water-soluble fertilizer every 7 days, and at the same time, remove old leaves at the bottom of the plant in time to optimize the distribution of nutrients in the plant.

[0028] After 20 days of bolting and flowering induction culture, the main stems of white celery, yellow celery, and red celery plants all showed significant elongation (one plant of each variety can be selected and shown in the image). Figure 1 (C) Different varieties exhibit varying degrees of bolting. Among them, white celery initiates the bolting process earliest, with a significantly higher main stem elongation than other varieties, and it is the first to form umbel-shaped inflorescences.

[0029] Example 2 Screening of vernalization duration for three hollow celery varieties 1 Seedling selection 30 seedlings of white celery, yellow celery and red celery with healthy growth, no pests and diseases, about 8-10 cm in height and 4 true leaves were selected. Each variety was randomly divided into 3 groups, with 3 replicates in each group to ensure that the growth status and leaf number of the seedlings in each group were completely consistent. Routine daily management was carried out during the seedling stage, and a large amount of element water-soluble fertilizer was applied once before vernalization treatment to strengthen seedlings.

[0030] 2 Low temperature vernalization treatment Each variety was placed in an artificial climate incubator for low temperature vernalization treatment. The culture environment was uniformly set as follows: temperature 8℃ during light period, temperature 4℃ during dark period, light duration 12h / dark duration 12h, light intensity 200 μmol·m -2 ·s -1 For white celery, yellow celery and red celery, the vernalization duration gradient was set as 30d, 45d and 60d. The seedling substrate was kept moist during vernalization, and no fertilization was performed.

[0031] 3 Bolting induction After the vernalization treatment was completed, all treatment groups were transferred to a light incubator for bolting induction. The culture environment was as follows: temperature 22℃ during light period, temperature 18℃ during dark period, light duration 16h / dark duration 8h, light intensity 400 μmol·m -2 ·s -1 White light LED lamp. High phosphorus type water-soluble fertilizer was applied every 7 days, and old leaves at the bottom of the plants were removed in time.

[0032] 4 Bolting induction result observation and vernalization duration screening After 30d of bolting induction treatment, the bolting phenotype of the plants in each treatment group was statistically analyzed. The bolting rate was defined as the percentage of the number of plants with obvious bolting main stems (main stem length ≥1cm) to the total number of plants in the treatment group. The bolting rate of different celery varieties under the conditions of vernalization treatment for 30d, 45d and 60d is shown in Table 1.

[0033] Table 1 Comparison of vernalization duration and bolting rate of three hollow celery varieties

[0034] As can be seen from the results of Table 1, the springing of white celery, yellow heart celery and red celery all failed to complete bolting after 30d of vernalization; the bolting rates of white celery, yellow heart celery and red celery were 49.9%, 42.2% and 35.5% respectively after 45d of vernalization; and the bolting rates of white celery, yellow heart celery and red celery were increased to 100%, 100% and 98.8% respectively after 60d of vernalization. It can be seen that the vernalization time of the three varieties of white celery, yellow heart celery and red celery has variety specificity, and the vernalization time of 60d can significantly promote the bolting process of the three varieties, among which white celery responds most significantly to vernalization, and red celery is relatively lagging behind. The present embodiment determines the optimal vernalization time of different celery varieties, and provides a technical reference for precise regulation and efficient cultivation of the reproductive growth stage of celery.

[0035] Example 3 Verification of the Induction Temperature-Sunlight Synergy of Celery Variety White Celery 1. Seedling selection Example 1 White celery is the earliest celery variety to start bolting, therefore, 30 healthy, disease-free, 8-10cm tall seedlings with four true leaves were selected and randomly divided into three groups (control group, experimental group 1, experimental group 2, experimental group 3) for three repeated experiments to ensure that the seedlings in each group grow uniformly and have no difference in leaf number. The seedlings were managed daily, and a large amount of element water-soluble fertilizer was applied once before vernalization to strengthen the seedlings.

[0036] 2. Low-temperature vernalization The selected seedlings were transplanted into seedling pots (7cm in diameter and 7.5cm in height) containing seedling substrate (mass ratio of grass carbon, vermiculite and perlite 3:2:1) and placed in an artificial climate incubator for low-temperature vernalization. The culture environment was 8℃ during light period and 4℃ during dark period, with a light / dark cycle of 12h / 12h and a light intensity of 200μmol·m -2 ·s -1 , and the light source was white LED light. The plants were vernalized for 60d, during which the seedling substrate was kept moist and no fertilizer was applied.

[0037] 3. Bolting induction (1) Control group (temperature-sunlight synergy) After 60d of low-temperature vernalization, the plants were transferred to a light incubator for bolting induction. The culture environment was 22℃ during light period and 18℃ during dark period, with a light / dark cycle of 16h / 8h and a light intensity of 400μmol·m -2 ·s -1 , and the light source was white LED light. High-phosphorus water-soluble fertilizer was applied every 7d, and the old leaves at the bottom of the plants were removed in time.

[0038] (2) Experimental group 1 (short-day, breaking the sunlight synergy) Cultivation environment: only change the light parameter, keep the temperature parameter consistent with the experimental group (22℃ during light, 18℃ during darkness), adjust to short day: light 12h / darkness 12h, light intensity 400 pmol m -2 ·s -1 , white light LED lamp. Every 7d, apply high phosphorus type water-soluble fertilizer, and timely remove the old leaves at the bottom of the plant.

[0039] (3) Experiment 2 group (temperature deviation, destroy temperature synergy) Cultivation environment: only change the temperature parameter, keep the light parameter consistent with the experimental group (light 16h / darkness 8h, light intensity 400 pmol m -2 ·s -1 ), adjust to temperature deviation: light 18℃, darkness 14℃. Every 7d, apply high phosphorus type water-soluble fertilizer, and timely remove the old leaves at the bottom of the plant.

[0040] (4) Experiment 3 group (light intensity deviation, weak light condition) Cultivation environment: only change the light intensity parameter, keep the day length and temperature consistent with the control group (light 16h / darkness 8h, temperature 22℃ during light, temperature 18℃ during darkness), the light intensity of day and night is adjusted to 200 pmol m -2 ·s -1 . Every 7d, apply high phosphorus type water-soluble fertilizer, and timely remove the old leaves at the bottom of the plant.

[0041] 4. Results observation and synergy verification Observe the plants in each treatment group for 30d, record the bolting and flowering process. First bolting time: take the node of the first plant main stem length about 1cm, record the time point. Average bolting rate: statistics of 20d, the number of plants forming basic umbrella inflorescence accounts for the percentage of the total number of plants in the treatment group; each treatment is repeated 3 times, the average value of 3 times is the average bolting rate of the treatment. Average flowering rate: statistics of 30d, the number of plants with the outermost small flowers of the inflorescence accounts for the percentage of the total number of plants in the treatment group; each treatment is repeated 3 times, the average value of 3 times is the average flowering rate of the treatment. The results are shown in Table 2.

[0042] Table 2 Influence of different bolting and flowering induction conditions on bolting and flowering

[0043] From Table 2, it can be seen that during the bolting and flowering induction stage, the light intensity is 400 pmol m -2 ·s -1The synergistic temperature-sunlight-light intensity conditions (control group), compared to experimental group 1 (which disrupted sunlight synergy), experimental group 2 (which disrupted temperature synergy), and experimental group 3 (which had light intensity deviation), significantly shortened the first bolting time and greatly increased the average bolting rate at 20 days and the average flowering rate at 30 days. This fully demonstrates that the synergistic effect between suitable temperature, sunshine duration, and light intensity is a key factor in promoting bolting and flowering in 'Baiqin' celery. Example 2 verified the synergistic effect of bolting and flowering induction conditions from three dimensions: temperature, sunshine duration, and light intensity, by setting up a control group and multiple experimental groups for the hollow celery variety 'Baiqin'. The synergistic conditions defined in this invention provide precise and effective technical support for the artificial regulation of bolting and flowering in hollow celery varieties, and have important practical significance for the breeding and cultivation management of hollow celery during its reproductive growth stage.

[0044] Example 4: Comparison of vernalization and bolting of three solid celery varieties 1. Seedling selection Shenqin No. 3, Yuyuan Queen, and Ventura were planted in a light-controlled incubator with the following conditions: temperature 22℃ during the light period, temperature 18℃ during the dark period, light duration 14h / dark duration 10h, and light intensity 300μmol·m⁻¹. -2 ·s -1 The light source is a white LED light. When the plants have at least 4 true leaves, select 30 healthy, disease-free seedlings of each of the following varieties (Shenqin No. 3, Yuyuan Queen, and Ventura) that are approximately 8-10cm tall and growing uniformly (choose one seedling from each variety). Figure 2 (A) Perform vernalization treatment. Before vernalization treatment, apply a water-soluble fertilizer containing macronutrients to strengthen the seedlings.

[0045] 2. Low-temperature vernalization treatment Seedlings of all varieties were placed in an artificial climate incubator for low-temperature vernalization treatment. The culture environment was uniformly set as follows: 8℃ during the light period, 4℃ during the dark period, 12h light / 12h dark period, and 200 μmol·m⁻² light intensity. -2 ·s -1 The light source is a white LED light. For the three varieties Shenqin No. 3, Yuyuan Queen, and Ventura, three groups were set up with vernalization duration gradients of 60 days, 90 days, and 120 days respectively; at 120 days of vernalization, one plant of each variety was randomly selected... Figure 2 Medium B. During vernalization, keep the seedling substrate moist and do not fertilize.

[0046] 3. Bolting and flowering induction After vernalization, all treatment groups were transferred to a light-controlled incubator for bolting and flowering induction. The incubation environment was as follows: 22℃ during the light period, 18℃ during the dark period, 16h light / 8h dark period, and 400μmol·m² light intensity. -2 ·s-1 The light source is a white light LED lamp; after 25 days of treatment, each variety has one plant selected Figure 2 C. Every 7 days, the plants were applied with a high-phosphorus type of water-soluble fertilizer, and the old leaves at the bottom of the plants were removed in time.

[0047] 4. Result observation and analysis of vernalization duration After 30 days of bolting induction treatment, the bolting phenotype of the plants in each treatment group was statistically analyzed. The bolting rate was defined as the percentage of the number of plants with obvious bolting main stems (main stem length ≥ 1 cm) to the total number of plants in the treatment group, and the average value was taken from three repeats of each treatment. The bolting rate of different celery varieties under the conditions of vernalization for 60 days, 90 days, and 120 days is shown in Table 3.

[0048] Table 3 Comparison of vernalization duration and bolting rate of three solid celery varieties

[0049] As can be seen from Table 3, when vernalized for 60 days, Shenshen No. 3, Yuyuan Queen, and Wentulala could not bolt; when vernalized for 90 days, the bolting rates of the three varieties were 44.4%, 31.1%, and 23.3%, respectively; when vernalized for 120 days, the bolting rates were significantly improved, reaching 100% for Shenshen No. 3, 95.6% for Yuyuan Queen, and 94.4% for Wentulala. It can be seen that the three solid celery varieties, Shenshen No. 3, Yuyuan Queen, and Wentulala, need to undergo a certain duration of vernalization to complete bolting, and within a certain range, the vernalization duration is positively correlated with the bolting rate, among which Shenshen No. 3 responds most significantly to vernalization, and Wentulala is relatively lagging behind. This embodiment clearly defines the vernalization duration requirements of different solid celery varieties, providing a technical basis for precise regulation and cultivation management of the reproductive growth stage.

[0050] Example 5 Application of Hollow Celery and Solid Celery Hybrid Breeding under Greenhouse Cultivation Conditions 1. Seedling cultivation and vernalization treatment Solid celery cultivation: The solid celery Yuyuan Queen was sown in the seedling substrate plug, and when the first true leaf of the plant fully expanded, the plant was transplanted into a seedling pot (7 cm in diameter and 7.5 cm in height) sown in the above substrate. After 40 days (seedlings reached 4 true leaves, plant height was about 8-10 cm), a large amount of element water-soluble fertilizer was applied once to strengthen the seedlings, and all plants were subjected to vernalization treatment according to the method of Example 1; Hollow celery cultivation: On the day when the solid celery entered the vernalization treatment, hollow celery white celery was cultivated according to the method of cultivating solid celery Yuyuan Queen, and when the seedlings reached 4 true leaves (about 40 days), the plant height was about 8-10 cm, and the vernalization treatment was carried out according to the method of Example 1; 2. Bolting and flowering induction and observation of flowering period Synchronization of vernalization treatment: after 100 days of vernalization treatment for solid celery and 60 days of vernalization treatment for hollow celery, the two types of celery were simultaneously removed from the vernalization treatment and transferred to a light incubator for bolting induction. The incubation environment was as follows: 22°C during light period and 18°C during dark period, 16h light period / 8h dark period, and light intensity of 400 μmol·m-2s-1, with white LED light as the light source. High-phosphorus water-soluble fertilizer was applied every 7 days, and the old leaves at the bottom of the plants were removed in time. -2 -1

[0051] 3 Synchronization of bolting process During the bolting induction period, the two types of celery plants (solid celery Yu Yuanguan Queen and white celery) were set with a fixed observation period, and the bolting growth dynamics were recorded continuously. The specific observation results are as follows: At 15 days of induction and cultivation, both types of plants showed the initial characteristics of main stem elongation: the average height of the main stem of solid celery Yu Yuanguan Queen was 5.5 cm, and that of white celery was 9.2 cm, and both types of plants entered the rapid growth period of the main stem.

[0052] At 20 days of induction and cultivation, the average height of the main stem of solid celery Yu Yuanguan Queen and white celery reached 16.7 cm and 21.3 cm, respectively; at this stage, the bolting height of some single plants tended to be consistent, and the bolting processes of the two types of plants were basically synchronized, without showing obvious time difference.

[0053] At 25 days of induction and cultivation, solid celery Yu Yuanguan Queen plants and white celery plants that had shown small flower blooming characteristics were selected and transferred to a special greenhouse with sufficient space (specific location: Shanghai Academy of Agricultural Sciences Fengpu Branch; greenhouse environmental conditions: temperature about 20~25°C), and the two types of celery plants were bagged using the same large net bag.

[0054] 4 Hybrid pollination and seed setting verification At 40~60 days of cultivation, both solid celery Yu Yuanguan Queen and white celery plants entered the full bloom period, at which time artificial pollination was used, with white celery as the father, and the mature pollen was collected and pollinated onto the stigmas of solid celery Yu Yuanguan Queen (mother). For each mother sterile inflorescence, 3~5 times of pollination treatment were continuously performed to ensure that all flowers on the inflorescence could fully receive fertile pollen and ensure the success rate of pollination. Among them, the father white celery that could provide pollination pollen had inflorescence and flower morphological characteristics as shown in Figure 3 A; the mother Yu Yuanguan Queen that could receive external pollen had inflorescence and flower morphological characteristics as shown in Figure 3 ​​As shown in Figure B. To ensure nutrient supply to the hybrid fruits, unpollinated lateral branches and redundant inflorescences were promptly pruned after pollination, and a high-phosphorus and potassium-rich fertilizer was applied via root irrigation to guarantee nutrient supply to the pollinated fruits. Twenty days after pollination, 90% of the pollinated flowers had formed young fruits and showed obvious signs of enlargement. Approximately 35-45 days after pollination, the hybrid fruits began to naturally change color and turn yellow. Figure 3 (C)

[0055] 5 F1 generation hybrid seed germination Simultaneously, hybrid seeds and self-pollinated seeds of the male parent, white celery, were harvested. After soaking in distilled water for 12 hours, they were transferred to petri dishes containing moistened filter paper, with 300 seeds per dish. These were then placed in a dark incubator at 25°C. After 10 days, the germination rate (percentage of germinated seeds out of the total) was recorded. The number of self-pollinated white celery seeds (…) Figure 3 (D) and hybrid seeds ( Figure 3 The germination rates of E and E were 96.3% and 95.3% respectively, with no significant difference.

[0056] The above results confirm that after the flowering periods of hollow celery and solid celery are precisely matched by the method of the present invention, hybridization pollination can be successfully completed, and high-quality hybrid seeds with a germination rate of over 95% can be obtained stably, which fully meets the requirements of celery hybridization breeding for seed quality.

[0057] Example 6: Application of artificial vernalization combined with greenhouse cultivation in bolting, flowering, and hybridization This study first carefully cultivated a small number of Yuyuan Queen celery plants in an artificially controlled incubator to ensure their healthy growth and vernalization, and then transplanted them to a greenhouse to induce flowering, thereby achieving hybridization with multiple different celery varieties.

[0058] 1. Seedling planting and vernalization treatment Sterile line cultivation: Seedlings of Yuyuan Queen were cultivated according to the cultivation method in Example 5. When the plants grew to the stage of 4 true leaves and 8-10cm in height, they were transferred to an artificial climate chamber on December 20, 2025, and vernalization treatment was carried out strictly according to the temperature, time and light parameters specified in Example 1.

[0059] Fertility line cultivation: Several solid celery varieties with excellent comprehensive traits, such as Shenqin No. 3 and Ventura, were selected as the male parent for hybridization. Sowing was completed in the experimental field of Shanghai Academy of Agricultural Sciences in November 2024 to ensure that the growth cycle of the male parent plants and the female parent (Yuyuan Queen) can be effectively connected.

[0060] 2. Transplanting and Bolting / Flowering Induction After the vernalization period of the Queen of Yu Garden ended on April 20, 2025, the Queen of Yu Garden was immediately transplanted to a plastic greenhouse in Shanghai (see plant details). Figure 4Fig. 2. The flowering process of Yuyuan Huanghou. A) The flowering process of Yuyuan Huanghou. B) The flowering process of Yuyuan Huanghou. C) The flowering process of Yuyuan Huanghou. D) The flowering process of Yuyuan Huanghou.From April 20 to April 30, the average temperature in the greenhouse during the day was about 26°C, and the average temperature at night was about 17°C. After transplanting, no additional light was provided, the soil was kept moist, and every 10 days, a high-phosphorus water-soluble fertilizer was applied, and the old leaves at the bottom were removed in a timely manner, leaving 6-7 functional leaves per plant.

[0061] 3 Flowering observation and hybridization pollination 25 days after transplanting (all plants saw Figure 4 B), Yuyuan Huanghou formed a raceme, and the small flowers were in bud. 35 days after transplanting, it entered the full bloom period, coinciding with the flowering period of Shenqin No. 3 and Venturale, etc. solid core celery varieties sown in November 2024. From May 25 to June 5, fresh pollen of Shenqin No. 3 and Venturale was collected every day from 9:00 to 11:00, and was given to the stigmatic stigma of Yuyuan Huanghou, and was bagged. 20 days after pollination (all plants saw Figure 4 C), then the fruits gradually enlarged and began to change color (D). Figure 4

[0062] As can be seen, using the above method, the natural seasonal restrictions can be broken, and the celery "two seasons of breeding in a year" can be realized. Compared with the period of celery seedlings in low temperature and short day length (December to the following March) overwintering and then inducing bolting and flowering in high temperature and long day length (April to May) under natural conditions, the period is greatly shortened. According to the above method, the hollow celery from 4-6 leaf seedlings to flowering only needs 70-95 days (45-60 days of vernalization treatment + 25-35 days of bolting and flowering induction), and the solid core celery needs 115-155 days (90-120 days of vernalization treatment + 25-35 days of bolting and flowering induction). Compared with the "cross-year breeding" under natural conditions, the period is shortened by about 40%-50%, and the breeding generation alternation speed is increased by about 1 times, which can quickly complete multi-generation excellent trait selection.

[0063] The standardization experimental material with consistent plant growth state and controllable physiological process can be obtained by the above method, and a stable experimental system is provided for the research on the mechanism of vernalization, the photoperiod regulation pathway and flower organ development. Compared with the prior art, the celery chloroplast vernalization and bolting flowering system is constructed by accurately regulating the temperature and the length of sunshine, and the following remarkable beneficial effects are obtained compared with the prior art: ① controllability and high efficiency: the bolting and flowering process is artificially controlled by the present application through the day and night temperature ratio, the day and night light length ratio and the treatment length, and the influence of the uncertainty of the natural environment is avoided. ② wide applicability and strong pertinence: the present application is the first to formulate a differential low-temperature vernalization treatment length scheme for the biological characteristic differences of the bolting of multiple hollow celery varieties (including white celery, red celery and yellow heart celery) and the resistance to bolting of solid celery varieties (Ventura, Shenqin No. 3 and Yuyuan Queen), which effectively solves the problem of limited applicability of the prior art and can be widely applied to the induction treatment of different types of celery varieties. Especially in hybrid breeding, the core problem of different varieties not meeting the flowering period is successfully solved by combining early planting with accurate vernalization regulation. ③ simple operation, and the celery two-season breeding mode can be realized: the required regulation parameters of the present application are clear and easy to control, and the operation is simple and easy to implement. A 1000L incubator can accommodate 800-1200 celery seedlings for vernalization, and after vernalization, the seedlings can be transplanted to the open field or greenhouse for cultivation, which can effectively realize the one-year two-season cultivation mode of celery, avoid the need for fixed winter vernalization, and overcome the seasonal limitation of cross-year flowering.

[0064] Although the above embodiment describes the present application in detail, it is only a part of the embodiments of the present application, not all the embodiments, and other embodiments can be obtained according to the present embodiment without creativity, which belong to the protection scope of the present application.

Claims

1. A method for regulating vernalization and inducing bolting in Apium graveolens, characterized by, The method comprises the following steps: 4-6 pieces of true leaf celery seedlings are selected for vernalization treatment to obtain celery plants; the vernalization treatment is light and dark alternating culture; the light and dark alternating culture has a light duration of 11-13 hours and a dark duration of 11-13 hours per day; during the vernalization treatment, the temperature during light is 6-9 DEG C, and the temperature during darkness is 2-5 DEG C; After the vernalization treatment, the celery plants are subjected to bolting and flowering induction; the bolting and flowering induction is light and dark alternating culture; the light and dark alternating culture has a light duration of 15-17 hours and a dark duration of 7-9 hours per day; during the bolting and flowering induction, the temperature during light is 22-25 DEG C, and the temperature during darkness is 18-21 DEG C.

2. The method of claim 1, wherein, The light intensity is 100-200 μmol·m -2 ·s -1 during the vernalization treatment, and the light intensity is 300-400 μmol·m -2 ·s -1 during the bolting and flowering induction. The light source comprises a white light lamp.

3. The method of claim 1, wherein, The celery variety comprises a hollow celery variety and / or a solid celery variety.

4. The method of claim 3, wherein, The vernalization treatment duration of the hollow celery variety is 45-60 days; the vernalization treatment duration of the solid celery variety is not less than 90 days.

5. The method according to claim 3 or 4, characterized in that, The hollow celery variety comprises at least one of the following: white celery, red celery and yellow heart celery; The solid celery variety comprises at least one of the following: Ventura, Shenqin No. 3 and Yu Garden Queen.

6. The method of claim 1, wherein, Before the vernalization treatment, a robust seedling fertilizer is applied once.

7. The method of claim 1, wherein, During the bolting and flowering induction, a high-phosphorus fertilizer is applied every 7-10 days; the high-phosphorus fertilizer is applied by foliar spraying and root irrigation.

8. The method of claim 1, wherein, The vernalization treatment or the bolting and flowering induction is carried out in at least one of the following scenarios: an artificial climate chamber, a greenhouse and a big shed.

9. The method for regulating vernalization and inducing bolting and flowering of celery according to any one of claims 1-8 is applied to rapid selection of excellent celery varieties.

10. Use according to claim 9, characterized in that, The rapid selection comprises the following steps: during hybrid pollination, the hollow celery variety is used as the male parent, the solid celery variety is used as the female parent, and continuous pollination is performed 3-5 times; after breeding, F1 hybrid seeds are obtained.

Images