Cultivation method of mangrove plant kandelia candel seedlings

Abstract

The invention discloses a mangrove plant kandelia candel seedling cultivation method, and belongs to the field of mangrove plant seedling cultivation methods. The method comprises the four steps of seed pretreatment, seed hormone soaking, seed hormone spraying, seedling hormone foliage spraying and rhizosphere injection. By means of the formula hormone seedling raising method, the germination rate and the germination speed of kandelia candel seeds can be increased, rapid cultivation of kandelia candel seedlings is achieved, a new seedling cultivation thought is provided for kandelia candel intertidal zone transplanting and artificial afforestation, and the formula hormone seedling raising method has important scientific and social significance.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of mangrove plant breeding and seedling raising method, and particularly relates to a method for promoting the cultivation of Kandelia candel seedlings. BACKGROUND

[0002] Mangrove forest is a coastal intertidal zone in the tropics and subtropics, which is periodically flooded by tidal water and is composed of evergreen shrubs or trees with mangrove plants as the main body. It plays an extremely important role in purifying seawater, preventing wind and waves, promoting siltation and protecting beaches, and protecting embankments. Kandelia candel is the most widely distributed species among mangrove plants in China, and it is distributed in Guangdong, Guangxi, Fujian and other places, and it has also been introduced in Zhejiang. However, with the increase of latitude, the crown height of Kandelia candel tends to decrease. Due to economic development and human activities, long-term unreasonable use of resources has led to a decrease in the area of domestic mangrove forests. In order to improve the success rate of Kandelia candel afforestation and ecological restoration ability, the research on Kandelia candel seedling cultivation is very important.

[0003] At present, there are problems such as slow seed germination, low plant growth rate and high time cost in Kandelia candel seedling cultivation. Therefore, it is of great significance to improve the cultivation speed of Kandelia candel seedlings through efficient seed germination and seedling raising technology to improve the efficiency of artificial afforestation of mangrove forests.

[0004] Using hormone to promote seed germination and seedling growth is a new and rapidly developing plant seedling and cultivation technology, which has been studied more in many herbaceous plants, but less in woody plants, especially in Kandelia candel, which has not been reported. Compared with traditional cultivation methods, using hormone to cultivate plants can realize rapid seedling raising in a short time and improve the development rate, so as to realize the rapid growth of Kandelia candel seedlings. SUMMARY

[0005] The purpose of the present application is to provide a method for cultivating Kandelia candel seedlings.

[0006] To solve the above problems, the technical scheme adopted by the present application is as follows: A method for cultivating Kandelia candel seedlings, comprising the following steps: (1) The Kandelia candel embryo axis seeds with uniform size, no obvious pests and diseases, thick and long embryo axis and dark green or dark brown color are soaked and disinfected with carbendazim solution for 20-30 min, and then rinsed with clean water for 2-3 times; (2) The Kandelia candel seeds treated in step (1) are soaked in gibberellin solution for 7 h, and the surface water is drained; (3) The Kandelia candel seeds treated in step (2) are sown in a seedling pot filled with substrate, and germination cultivation is carried out under LED light, and during the period, the surface of the seeds is sprayed with gibberellin solution once every 5 days; (4) Select the Kandelia candel seedlings that have germinated and grown to 4-6 true leaves, 15-20cm tall and of uniform growth status in step (3), plant them in seedling pots filled with substrate, and cultivate the seedlings under LED light conditions. During this period, spray the seedling leaves with a mixed solution of gibberellin and 6-benzylaminopurine every 5 days and inject the root zone with gibberellin solution once. After 60-90 days of cultivation, harvest the seedlings. In step (1), the concentration of the carbendazim solution is 0.5 g / L, and the soaking temperature is 20~30℃; In step (2), the concentration of the gibberellin solution is 150~200 mg·L. -1 The soaking temperature is 20~30℃; In step (3), the substrate is coastal mudflat sediment; the LED lighting conditions are: light intensity of 150~200 μmol·m -2 ·s -1 The light quality is red light: blue light: green light = 3:1:1, and the illumination duration is 12 hours per day. -1 The concentration of the gibberellin solution is 150~200 mg·L. -1 The amount of gibberellin solution applied is such that the seed coat is moistened but the liquid does not drip. In step (4), the substrate is coastal mudflat sediment; the LED lighting conditions are: light intensity of 150~200 μmol·m -2 ·s -1 The light quality is red light: blue light: green light = 3:1:1, and the illumination duration is 12 hours per day. -1 The mixed solution of gibberellin and 6-benzylaminopurine was prepared at a concentration of 100 mg·L⁻¹. -1 Gibberellin solution with a concentration of 10 mg·L -1 The solution was prepared by mixing equal volumes of gibberellin and 6-benzylaminopurine solution. The spraying rate of the gibberellin and 6-benzylaminopurine mixture was 2 mL / plant. The concentration of the gibberellin solution was 75 mg·L⁻¹. -1 The injection volume of the gibberellin solution is 3 mL / plant.

[0007] Application of Kandelia candel seedlings prepared by the above method in mangrove ecological restoration projects.

[0008] Application of Kandelia candel seedlings prepared by the above method in the construction of coastal mudflat vegetation.

[0009] Application of Kandelia candel seedlings prepared by the above method in the cultivation of mangrove seedlings in a mangrove nursery.

[0010] The beneficial effects of this invention are as follows: This invention employs the application of hormones, setting specific hormone types (gibberellin, 6-benzylaminopurine) and application methods (spraying, injection), and applying compound hormones to obtain the optimal conditions for promoting the cultivation of Kandelia candel seedlings, thereby achieving rapid germination of Kandelia candel seeds and rapid and high-quality seedling cultivation. Attached Figure Description

[0011] Figure 1 Germination rate of Kandelia candel seeds after spraying with different concentrations of hormones.

[0012] Figure 2 The growth of Kandelia candel seedlings under different concentrations of hormones sprayed on their leaves.

[0013] Figure 3 Growth of Kandelia candel seedlings after rhizosphere injection with different concentrations of hormones.

[0014] Figure 4 The growth of Kandelia candel seedlings under a combined treatment of foliar spraying and root injection. Detailed Implementation

[0015] The present invention will be further described in detail below with reference to specific embodiments. It should be emphasized that the following description is only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0016] Example 1: Effects of different concentrations of hormone spraying on the germination rate of Kandelia candel seeds (1) Select Kandelia candel seeds that are uniform in size, free from obvious pests and diseases, with thick and long hypocotyls and a dark green or dark brown color. Soak the seeds in carbendazim solution for 20 minutes for disinfection, and then rinse them with clean water 2-3 times. The concentration of the carbendazim solution is 0.5 g / L, and the soaking temperature is 20-30℃.

[0017] (2) The experimental group was set with gibberellin (GA3) solution immersion concentration gradients of 100, 150, 200, 300, and 350 mg·L. -1 Meanwhile, the control group was soaked in water at a temperature of 20-30℃. The seeds of the autumn eggplant treated in step (1) were placed in GA3 solutions of different concentrations and water, soaked for 7 hours, and then drained.

[0018] (3) The seeds treated in step (2) were sown in seedling pots filled with substrate (coastal mudflats) and germinated under LED light. During this period, the seeds of each experimental group were sprayed with the corresponding GA3 solution according to the same concentration gradient as in step (2), while the control group was sprayed with water. The spraying frequency was once every 5 days, and the spraying amount was such that the seed coat was evenly moistened and the liquid droplets did not drip. The LED light conditions were: light intensity of 150~200 μmol·m -2 ·s -1 The light quality is red light: blue light: green light = 3:1:1, and the illumination duration is 12 hours per day. -1 Other conditions during cultivation include: maintaining an ambient temperature of 28-32℃, a relative humidity of 80-90%, and watering regularly to keep the substrate in the seedling trays moist but not waterlogged. Observe the seed germination status daily and record the germination rate.

[0019] Figure 1 The results of an experiment on the germination rate of Kandelia candel seeds treated with different concentrations of hormones. Figure 1 It can be seen that the concentrations are 150 and 200 mg·L. -1 The GA3 solution significantly promoted the germination of Kandelia candel seeds. Overall, the two concentration treatment groups showed the fastest germination rate, reaching 100% by day 25 of cultivation, indicating that GA3 solution spraying within this concentration range can effectively promote seed germination of Kandelia candel within a certain timeframe.

[0020] Example 2: Effects of foliar spraying of different concentrations of hormones on the growth of Kandelia candel seedlings (1) Select Kandelia candel seeds that are uniform in size, free from obvious pests and diseases, with thick and long hypocotyls and a dark green or dark brown color. Soak the seeds in carbendazim solution for 20 minutes for disinfection, and then rinse them with clean water 2-3 times. The concentration of the carbendazim solution is 0.5 g / L, and the soaking temperature is 20-30℃.

[0021] (2) Place the eggplant seeds treated in step (1) in a solution with a concentration of 150 mg·L⁻¹ -1 The sample was soaked in a GA3 solution for 7 hours, then removed and drained of surface moisture. The soaking temperature was 20-30°C.

[0022] (3) The seeds treated in step (2) were sown in seedling trays containing substrate (coastal mudflats) and germinated under LED light. During this period, the seed surface was sprayed with a solution of 150 mg·L⁻¹ every 5 days. -1 The GA3 solution was sprayed at a rate sufficient to evenly wet the seed coat without dripping. The LED lighting conditions were: light intensity of 150–200 μmol·m⁻². -2 ·s -1The light quality is red light: blue light: green light = 3:1:1, and the illumination duration is 12 hours per day. -1 Other conditions during the cultivation period are: ambient temperature controlled at 28~32℃, relative humidity controlled at 80~90%, and regular watering to keep the substrate in the seedling pot moist but not waterlogged.

[0023] (4) Select the Kandelia candel seedlings that have germinated and grown to 4-6 true leaves, 15-20cm tall and of uniform growth status from step (3), and plant them in seedling pots filled with substrate (coastal mudflat bottom mud). Cultivate the seedlings under LED light conditions, and set different hormone spraying treatments during the period, as follows: GA3 solution concentrations of 25, 50, 75, 100 and 125 mg·L -1 6-Benzylaminopurine (6-BA) solutions were prepared at concentrations of 10, 30, 50, 150, and 250 mg·L⁻¹. -1 Meanwhile, water was used as a control group. The spraying method involved evenly spraying 2 mL of the corresponding solution onto the leaves of each seedling, with a spraying frequency of once every 5 days. The LED lighting conditions were: light intensity of 150–200 μmol·m⁻². -2 ·s -1 The light quality is red light: blue light: green light = 3:1:1, and the illumination duration is 12 hours per day. -1 Other conditions during the cultivation period are: ambient temperature controlled at 28~32℃, relative humidity controlled at 80~90%, and regular watering to keep the substrate in the seedling pots moist but not waterlogged. Seedlings harvested after 90 days of cultivation are considered mature seedlings, and their various growth indicators are measured.

[0024] Figure 2 The results of an experiment on the growth of Kandelia candel seedlings under foliar spraying treatments with different concentrations of hormones. Figure 2 It can be seen that foliar spraying of 100 mg·L -1 GA3 solution or 10 mg·L -1 When treated with 6-BA solution, the plant height and leaf length growth of Kandelia candel seedlings were significantly increased compared to the control group. Specifically, 100 mg·L⁻¹ -1 The seedlings treated with GA3 solution reached their maximum height increase, at 11.44 ± 0.04 cm / plant; 10 mg·L -1 The seedlings treated with 6-BA solution achieved the maximum leaf length growth, which was 4.29 ± 0.08 cm / plant. These results indicate that foliar spraying with 100 mg·L⁻¹ BA solution is effective. -1 GA3 solution or 10 mg·L -1 6-BA solution can effectively improve the growth rate of Kandelia candel seedlings.

[0025] Example 3: Effects of rhizosphere injection of different concentrations of hormones on the growth of Kandelia candel seedlings (1) Select Kandelia candel seeds that are uniform in size, free from obvious pests and diseases, with thick and long hypocotyls and a dark green or dark brown color. Soak the seeds in carbendazim solution for 20 minutes for disinfection, and then rinse them with clean water 2-3 times. The concentration of the carbendazim solution is 0.5 g / L, and the soaking temperature is 20-30℃.

[0026] (2) Place the eggplant seeds treated in step (1) in a solution with a concentration of 150 mg·L⁻¹ -1 The sample was soaked in a GA3 solution for 7 hours, then removed and drained of surface moisture. The soaking temperature was 20-30°C.

[0027] (3) The seeds treated in step (2) were sown in seedling trays containing substrate (coastal mudflats) and germinated under LED light. During this period, the seed surface was sprayed with a solution of 150 mg·L⁻¹ every 5 days. -1 The GA3 solution was sprayed at a rate sufficient to evenly wet the seed coat without dripping. The LED lighting conditions were: light intensity of 150–200 μmol·m⁻². -2 ·s -1 The light quality is red light: blue light: green light = 3:1:1, and the illumination duration is 12 hours per day. -1 Other conditions during the cultivation period are: ambient temperature controlled at 28~32℃, relative humidity controlled at 80~90%, and regular watering to keep the substrate in the seedling pot moist but not waterlogged.

[0028] (4) Select the Kandelia candel seedlings that have germinated and grown to 4-6 true leaves, 15-20cm tall and of uniform growth status from step (3), and plant them in seedling pots filled with substrate (coastal mudflat bottom mud). Cultivate the seedlings under LED light conditions, and set different hormone injection treatments during the period, as follows: GA3 solution concentrations of 25, 50, 75, 100 and 125 mg·L. -1 The concentrations of 6-BA solutions were 10, 30, 50, 150, and 250 mg·L⁻¹. -1 Meanwhile, water was used as a control group. The injection method involved uniformly injecting 3 mL of the corresponding solution into the root zone of each seedling, with an injection frequency of once every 5 days. The LED lighting conditions were: light intensity of 150–200 μmol·m⁻². -2 ·s -1 The light quality is red light: blue light: green light = 3:1:1, and the illumination duration is 12 hours per day. -1 Other conditions during the cultivation period are: ambient temperature controlled at 28~32℃, relative humidity controlled at 80~90%, and regular watering to keep the substrate in the seedling pots moist but not waterlogged. Seedlings harvested after 90 days of cultivation are considered mature seedlings, and their various growth indicators are measured.

[0029] Figure 3The results of an experiment on the growth of Kandelia candel seedlings under rhizosphere injection treatment with different concentrations of hormones. Figure 3 It is known that injecting 75-100 mg / L into the rhizosphere... -1 GA3 solution or 250 mg·L -1 When treated with 6-BA solution, the growth rates of Kandelia candel seedlings in terms of plant height, number of leaves, leaf length, and leaf width were significantly increased compared to the control group. Specifically, 75 mg·L⁻¹ -1 The seedlings treated with GA3 solution reached their maximum height increase, at 5.84 ± 1.94 cm / plant; 100 mg·L -1 The seedlings treated with GA3 solution achieved the maximum leaf number increase, reaching 7 ± 2.55 leaves / plant. These results indicate that rhizosphere injection of 75 mg·L⁻¹ is effective. -1 Or 100 mg·L -1 GA3 solution can effectively improve the growth rate of Kandelia candel seedlings.

[0030] Example 4: Effects of combined foliar spraying and root injection of hormones on the growth of Kandelia candel seedlings (1) Select Kandelia candel seeds that are uniform in size, free from obvious pests and diseases, with thick and long hypocotyls and a dark green or dark brown color. Soak the seeds in carbendazim solution for 20 minutes for disinfection, and then rinse them with clean water 2-3 times. The concentration of the carbendazim solution is 0.5 g / L, and the soaking temperature is 20-30℃.

[0031] (2) Place the eggplant seeds treated in step (1) in a solution with a concentration of 150 mg·L⁻¹ -1 The sample was soaked in a GA3 solution for 7 hours, then removed and drained of surface moisture. The soaking temperature was 20-30°C.

[0032] (3) The seeds treated in step (2) were sown in seedling trays containing substrate (coastal mudflats) and germinated under LED light. During this period, the seed surface was sprayed with a solution of 150 mg·L⁻¹ every 5 days. -1 The GA3 solution was sprayed at a rate sufficient to evenly wet the seed coat without dripping. The LED lighting conditions were: light intensity of 150–200 μmol·m⁻². -2 ·s -1 The light quality is red light: blue light: green light = 3:1:1, and the illumination duration is 12 hours per day. -1 Other conditions during the cultivation period are: ambient temperature controlled at 28~32℃, relative humidity controlled at 80~90%, and regular watering to keep the substrate in the seedling pot moist but not waterlogged.

[0033] (4) Select the Kandelia candel seedlings that have germinated and grown to 4-6 true leaves, 15-20cm tall and of uniform growth status in step (3), and plant them in seedling pots filled with substrate (coastal mudflat bottom mud). Cultivate the seedlings under LED light conditions. During this period, different hormone spraying and injection combined treatments were set up. Each group was treated once every 5 days, as follows: Experimental group 1 was sprayed with 2mL of a mixed solution of GA3 and 6-BA (100mg·L) on the leaves of each plant each time. -1 GA3 solution with a concentration of 10 mg·L -1 The solution was prepared by mixing equal volumes of 6-BA solution, and simultaneously, 3 mL of GA3 solution (containing 100 mg·L⁻¹) was injected into the root zone. -1 GA3 solution with a concentration of 75 mg·L -1 (The solution was prepared by mixing equal volumes of GA3); Experimental group 2 was treated by foliar spraying 2 mL of a mixed solution of GA3 and 6-BA (with a concentration of 100 mg·L⁻¹) onto each plant each time. -1 GA3 solution with a concentration of 10 mg·L -1 (Prepared by mixing equal volumes of 6-BA solution), and simultaneously injecting 3 mL of a 75 mg·L solution into the rhizosphere. -1 The control group received GA3 solution; each plant was sprayed with 2 mL of water on the leaves and simultaneously injected with 3 mL of water into the root zone. The LED lighting conditions were: light intensity of 150–200 μmol·m⁻². -2 ·s -1 The light quality is red light: blue light: green light = 3:1:1, and the illumination duration is 12 hours per day. -1 Other conditions during the cultivation period are: ambient temperature controlled at 28~32℃, relative humidity controlled at 80~90%, and regular watering to keep the substrate in the seedling pots moist but not waterlogged. Seedlings harvested after 60 days of cultivation are considered mature seedlings, and their various growth indicators are measured.

[0034] Experimental results show that ( Figure 4 By day 60 of cultivation, the height growth and leaf number growth of the Kandelia candel seedlings in treatment group 2 reached their maximum values, which were 3.21±0.91 cm / plant and 5.8±1.41 leaves / plant, respectively.

[0035] In summary, during the seed germination stage of Kandelia candel, spraying with 150-200 mg / L of solution is recommended. -1 A GA3 solution can significantly accelerate seed germination. During the seedling stage of Kandelia candel, apply 2 mL of a mixture of 100 mg·L⁻¹ GA3 per plant per foliar spray. -1 GA3 solution and 10 mg·L -1 6-BA solution, 3 mL (75 mg / L) injected into the rhizosphere. -1The combined treatment with GA3 solution can effectively improve the growth rate of Kandelia candel seedlings.

[0036] The foregoing embodiments have described the specific content of the present invention. Those skilled in the art can easily make various modifications and alterations to the content of the present invention based on known principles. Therefore, the above embodiments do not represent the full scope of patent protection of the present invention. Thus, modifications based on the present invention that conform to the concepts defined in the claims also fall within the scope of protection of the claims.

Claims

1. A method for cultivating seedlings of the mangrove plant *Kandelia candel*, characterized in that: Includes the following steps: (1) Soak the seeds of the eggplant hypocotyl that are uniform in size, free from obvious diseases and pests, with thick and long hypocotyls and dark green or dark brown color in carbendazim solution for 20-30 minutes, and then rinse them with clean water 2-3 times. (2) Soak the eggplant seeds treated in step (1) in gibberellin solution for 7 hours and drain the surface moisture; (3) Sow the eggplant seeds treated in step (2) in a seedling pot filled with substrate and germinate them under LED light. Spray the seed surface with gibberellin solution every 5 days during the period. (4) Select the Kandelia candel seedlings that have germinated and grown to 4-6 true leaves, 15-20cm tall and of uniform growth status in step (3), plant them in seedling pots filled with substrate, and cultivate the seedlings under LED light conditions. During this period, spray the seedling leaves with a mixed solution of gibberellin and 6-benzylaminopurine every 5 days and inject the root zone with gibberellin solution once. Harvest the seedlings after 60-90 days of cultivation.

2. The method according to claim 1, characterized in that: In step (1), the concentration of the carbendazim solution is 0.5 g / L, and the soaking temperature is 20~30℃.

3. The method according to claim 1, characterized in that: In step (2), the concentration of the gibberellin solution is 150~200 mg·L. -1 The soaking temperature is 20~30℃.

4. The method according to claim 1, characterized in that: In step (3), the substrate is coastal mudflat sediment; the LED lighting conditions are: light intensity of 150~200 μmol·m -2 ·s -1 The light quality is red light: blue light: green light = 3:1:1, and the illumination duration is 12 hours per day. -1 The concentration of the gibberellin solution is 150~200 mg·L. -1 The amount of gibberellin solution applied is such that the seed coat is moistened but the liquid does not drip.

5. The method according to claim 1, characterized in that: In step (4), the substrate is coastal mudflat sediment; the LED lighting conditions are: light intensity of 150~200 μmol·m -2 ·s -1 The light quality is red light: blue light: green light = 3:1:1, and the illumination duration is 12 hours per day. -1 The mixed solution of gibberellin and 6-benzylaminopurine was prepared at a concentration of 100 mg·L⁻¹. -1 Gibberellin solution with a concentration of 10 mg·L -1 The solution was prepared by mixing equal volumes of gibberellin and 6-benzylaminopurine solution. The spraying rate of the gibberellin and 6-benzylaminopurine mixture was 2 mL / plant. The concentration of the gibberellin solution was 75 mg·L⁻¹. -1 The injection volume of the gibberellin solution is 3 mL / plant.

6. The application of Kandelia candel seedlings prepared by the method according to any one of claims 1 to 5 in mangrove ecological restoration projects.

7. The application of Kandelia candel seedlings prepared by the method according to any one of claims 1 to 5 in the construction of coastal mudflat vegetation.

8. The application of the Kandelia candel seedlings prepared by the method according to any one of claims 1 to 5 in the cultivation of mangrove seedlings in a mangrove plant nursery.

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