Indoor seedling raising method for mangrove plant red sea olive

Abstract

The invention discloses an indoor seedling raising method for mangrove plant red sea olive. The method comprises three stages of seed pretreatment, seed germination and seedling cultivation. The light environment, the temperature, the humidity, the nutrition supply and the salinity of the substrate are accurately regulated and controlled under the condition of full manual control by adopting the culture substrate with a specific proportion, and the dependence of traditional seedling culture on natural conditions is effectively overcome. According to the method, standardization and controllability of red sea olive seedling raising are achieved, the growth speed of red sea olive seedlings is remarkably increased, and the method is suitable for large-scale and annual seedling raising production and has important application value for mangrove forest wetland restoration and ecological engineering.

Description

Technical Field

[0001] This invention belongs to the field of plant cultivation technology, specifically relating to an indoor seedling cultivation method for the mangrove plant *Rhizophora stylosa*. Background Technology

[0002] Mangroves are a unique coastal wetland ecosystem dominated by plants of the Rhizophoraceae family, exhibiting both marine and terrestrial characteristics. They grow in the intertidal zone of tropical and subtropical coasts or at river estuaries, subject to periodic tidal inundation, and possess immense biodiversity. They are ecologically significant coastal habitats and considered an important marine resource. Mangroves provide ecological functions such as wave protection, shoreline conservation, siltation and land reclamation, water purification, sedimentation of organic matter and pollutants, and maintenance of biodiversity. Furthermore, mangrove ecosystems have a strong carbon sequestration capacity, playing a crucial role in mitigating global climate change. However, under the increasing influence of human disturbance and global climate change, mangroves are facing serious threats such as habitat fragmentation and loss, overexploitation, environmental pollution, and invasive species. Many mangrove forests are showing signs of gradual decline or even disappearance. Therefore, effectively protecting and restoring mangrove populations and maintaining the stability of mangrove ecosystems has become a vital task for ecological environmental protection.

[0003] Red Sea Olive ( Rhizophora stylosa As a preferred tree species for the ecological restoration of mangrove forests along my country's coast, *Rhizophora stylosa* is an evergreen shrub or small tree, widely distributed in tropical and subtropical coastal areas. Currently, *Rhizophora stylosa* mainly relies on tidal flat nurseries and open tidal flat nurseries for seedling propagation. However, these traditional seedling propagation methods are not only limited by natural conditions such as soil, water, temperature, and salinity, but also generally suffer from technical bottlenecks such as low seedling survival rate and long seedling cycle, making it difficult to meet the needs of large-scale, high-efficiency ecological restoration. In contrast, using indoor vertical cultivation facilities for seedling propagation allows for precise management of light, temperature, humidity, salinity, and nutrient supply in an artificially controlled environment, thereby achieving stable control of the seedling environment. This method not only effectively avoids the uncertainties of the natural environment but also significantly improves space utilization efficiency, shortens the seedling cycle, and accelerates seedling growth, providing a feasible path for the rapid, high-density, and large-scale cultivation of *Rhizophora stylosa* seedlings. Summary of the Invention

[0004] The purpose of this invention is to provide an indoor seedling cultivation method for the mangrove plant *Rhizophora stylosa*. This method optimizes the ratio and application of compound fertilizer and secondary nutrients to create a fully artificial seedling cultivation environment with precisely controllable light, temperature, humidity, salinity, and nutrient conditions. This invention effectively overcomes the technical bottlenecks of traditional nursery seedling cultivation, which are limited by natural conditions such as soil, climate, sunlight, and salinity. It enables the rapid, robust, standardized, and large-scale cultivation of *Rhizophora stylosa* seedlings, providing a stable and reliable seedling source for mangrove ecological restoration and coastal vegetation recovery.

[0005] To achieve the above-mentioned objectives, the present invention adopts the following technical solution: A method for indoor seedling cultivation of the mangrove plant *Rhizophora stylosa*, characterized by the following steps: (1) Seed pretreatment: Rinse the red olive seeds with clean water to remove surface impurities and dirt; then soak the seeds in a 1 g / L carbendazim solution for 15 min for disinfection. After disinfection, rinse them with clean water to obtain pretreated red olive seeds. (2) Seed germination: The pretreated red olive seeds are planted into seedling bags filled with culture substrate, leaving a 2cm gap between the bottom of the red olive seeds and the bottom of the seedling bag. After watering thoroughly, the seeds are placed in a smart greenhouse for germination and cultivation. The culture substrate is formulated by weight ratio as humus: sand: loess = 1:3:3. (3) Seedling cultivation: When the seeds of red sea olive germinate and grow 2-4 true leaves, select healthy seedlings with uniform growth, and place them together with the seedling bags in the intelligent greenhouse for seedling cultivation. The seedlings will be harvested after 90 days. The conditions for germination cultivation in step (2) are as follows: ① Illumination conditions: LED light source is used, with a spectral composition of 31% photons in the 400-499nm range, 11% in the 500-599nm range, 56% in the 600-700nm range, and 2% in the 701-780nm range. The illuminance is 200-300 μmol·m. -2 ·s -1 Light duration 6 hours / day; ② Ambient temperature and humidity: The ambient temperature should be controlled at 26~28℃, and the relative humidity should be controlled at 70%~90%; ③ Water management: Water regularly every day to keep the growing medium moist but not waterlogged.

[0006] The conditions for seedling cultivation in step (3) are as follows: ① Illumination conditions: LED light source is used, with a spectral composition of 31% photons in the 400-499nm range, 11% in the 500-599nm range, 56% in the 600-700nm range, and 2% in the 701-780nm range. The illuminance is 100-200 μmol·m. -2 ·s -1 Light exposure duration: 8 hours / day; ② Ambient temperature and humidity: The ambient temperature should be controlled at 28~30℃, and the relative humidity should be controlled at 70%~90%; ③ Water management: Water regularly every day to keep the growing medium moist but not waterlogged; ④ Nutritional supply: Fertilize once every 20 days; ⑤ Substrate salinity: The salinity of the culture substrate should be controlled at 15‰.

[0007] In step (3), the amount of fertilizer supplied per kg of culture substrate is: compound fertilizer 0.2~1.2g, calcium fertilizer 0.278~1.665g, and magnesium fertilizer 0.308~1.849g; The effective components of the compound fertilizer are N 15%, P2O5 15%, and K2O 15%; The calcium fertilizer is CaCl2; The magnesium fertilizer is MgSO4·7H2O.

[0008] The beneficial effects of this invention are as follows: The method of this invention effectively overcomes the dependence of traditional seedling cultivation methods on environmental factors such as natural soil, climate, light, and tidal salinity, significantly improves the growth rate of red sea olive seedlings, and provides a reliable technical guarantee for achieving rapid, high-density, standardized large-scale seedling cultivation. Attached Figure Description

[0009] Figure 1 This is a schematic diagram of indoor cultivation of red sea olive seedlings.

[0010] Figure 2 Screening of the amount of compound fertilizer to be applied during the seedling cultivation period of red sea olive.

[0011] Figure 3 Screening of calcium fertilizer application rates during the seedling cultivation period of red sea olive.

[0012] Figure 4 Screening of magnesium fertilizer application rates during the seedling cultivation period of red sea olive. Detailed Implementation

[0013] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0014] An indoor seedling cultivation method for the mangrove plant *Rhizophora stylosa* includes the following steps: (1) Seed pretreatment The seeds of the red olive were rinsed with clean water to remove surface impurities and dirt. Then, the seeds were soaked in a carbendazim solution for 15 minutes for disinfection. After disinfection, they were rinsed with clean water to obtain pretreated red olive seeds.

[0015] The concentration of the carbendazim solution was 1 g / L.

[0016] (2) Seed germination Pretreated red olive seeds were implanted into seedling bags filled with culture substrate, thoroughly watered, and then placed in a smart greenhouse for germination and cultivation.

[0017] The formula for the cultivation substrate, by weight ratio, is humus: sand: loess = 1:3:3.

[0018] There should be a 2cm gap between the bottom of the red olive seed and the bottom of the seedling bag.

[0019] The conditions for germination and cultivation are as follows: ① Illumination conditions: LED light source is used, with a spectral composition of 31% photons in the 400-499nm range, 11% in the 500-599nm range, 56% in the 600-700nm range, and 2% in the 701-780nm range. The illuminance is 200-300 μmol·m. -2 ·s -1 Light duration 6 hours / day; ② Ambient temperature and humidity: The ambient temperature should be controlled at 26~28℃, and the relative humidity should be controlled at 70%~90%; ③ Water management: Water regularly every day to keep the growing medium moist but not waterlogged.

[0020] (3) Seedling cultivation When the seeds of the red sea olive germinate and grow 2-4 true leaves, select healthy seedlings with uniform growth, and place them together with the seedling bags in the intelligent greenhouse for seedling cultivation. The seedlings can be harvested after 90 days.

[0021] The conditions for seedling cultivation are as follows: ① Illumination conditions: LED light source with a spectral composition of 31% photons in the 400-499nm range, 11% in the 500-599nm range, 56% in the 600-700nm range, and 2% in the 701-780nm range; illuminance of 100-200 μmol·m⁻¹. -2 ·s -1 Light exposure duration: 8 hours / day; ② Ambient temperature and humidity: The ambient temperature should be controlled at 28~30℃, and the relative humidity should be controlled at 70%~90%; ③ Water management: Water regularly every day to keep the growing medium moist but not waterlogged; ④ Nutrient supply: Fertilize once every 20 days. The amount of fertilizer per kg of cultivation substrate is as follows: Compound fertilizer (effective ingredients N 15%, P2O5 15%, K2O 15%): 0.2~1.2g; Calcium fertilizer (CaCl2): 0.278~1.665g; Magnesium fertilizer (MgSO4·7H2O): 0.308~1.849g; ⑤ Substrate salinity: The salinity of the culture substrate should be controlled at 15‰. Example 1: Screening of Compound Fertilizer Application Rate for Red Olive Seedling Cultivation

[0022] (1) Seed pretreatment: Rinse the red olive seeds with clean water to remove surface impurities and dirt; then soak the seeds in a 1 g / L carbendazim solution for 15 min for disinfection. After disinfection, rinse them with clean water to obtain pretreated red olive seeds.

[0023] (2) Seed germination: Pretreated red olive seeds were implanted into seedling bags filled with culture substrate, leaving a 2cm gap between the bottom of the red olive seeds and the bottom of the seedling bag. After watering thoroughly, the seeds were placed in an intelligent greenhouse for germination cultivation. The culture substrate was formulated by weight ratio as humus: sand: loess = 1:3:3. The germination cultivation conditions were as follows: LED light source was used, with a spectral composition of 31% of photons in the 400-499nm range, 11% in the 500-599nm range, 56% in the 600-700nm range, and 2% in the 701-780nm range, and a light intensity of 300 μmol·m. -2 ·s -1 Light exposure duration: 6 hours / day; ambient temperature: 26℃; relative humidity: 70%; water regularly every day to keep the substrate moist but not waterlogged.

[0024] (3) Seedling Cultivation: When the seeds of *Rhizophora stylosa* germinate and grow 2-4 true leaves, select healthy seedlings with uniform growth and place them, along with their seedling bags, back into the intelligent greenhouse for seedling cultivation. Different fertilization treatments are implemented during this period, as follows: compound fertilizer is applied every 20 days, with application amounts set at 0, 0.2, 0.4, 0.8, and 1.2 g / kg of the cultivation substrate. The effective components of the compound fertilizer are: 15% N, 15% P2O5, and 15% K2O. The seedling cultivation conditions are as follows: LED light source is used, with a spectral composition of 31% quanta in the 400-499nm range, 11% in the 500-599nm range, 56% in the 600-700nm range, and 2% in the 701-780nm range; the light duration is 8 h / d, and the light intensity is 100 μmol·m². -2 ·s -1 The ambient temperature was controlled at 28℃, and the relative humidity at 85%. The salinity of the substrate was monitored regularly using a salinity meter and adjusted with sea salt solution to maintain the salinity at 15‰. The substrate was watered regularly every day to keep it moist but not waterlogged. Seedlings harvested after 90 days of cultivation were considered mature seedlings, and their various indicators were measured.

[0025] Figure 2 The effects of different compound fertilizer application rates on the growth of *Rhizophora stylosa* seedlings. Figure 2It can be seen that the increase in plant height and leaf width of *Rhizophora stylosa* increases with the increase in compound fertilizer application, while the increase in leaf length shows a trend of first increasing and then decreasing with the increase in compound fertilizer application. The increases in plant height, number of leaves, and leaf width reach their maximum values ​​at a compound fertilizer application rate of 1.2 g / kg, which are 3.11 ± 0.39 cm / plant, 2.91 ± 0.28 leaves / plant, and 0.21 ± 0.03 cm / leaf, respectively. The increase in leaf length reaches its maximum value at a compound fertilizer application rate of 0.8 g / kg, at 0.48 ± 0.06 cm / leaf, followed by 1.2 g / kg. Therefore, a compound fertilizer application rate of 1.2 g / kg best promotes the overall growth performance of *Rhizophora stylosa* seedlings. Example 2: Screening of medium-dose calcium fertilizer application for red olive seedling cultivation

[0026] (1) Seed pretreatment: Same as in Example 1.

[0027] (2) Seed germination: Same as in Example 1.

[0028] (3) Seedling cultivation: When the seeds of *Rhizophora stylosa* germinate and grow 2-4 true leaves, select healthy seedlings with uniform growth and place them, along with their seedling bags, back into the intelligent greenhouse for seedling cultivation. During this period, different fertilization treatments are set as follows: compound fertilizer and calcium fertilizer are applied every 20 days. The amount of compound fertilizer applied each time is set at 1.2 g / kg, and the amount of calcium fertilizer applied each time is set at 0, 0.5, 1, 2, and 3 times the concentration (1 times the concentration is 0.555 g / kg of cultivation substrate). The effective components in the compound fertilizer are: 15% N, 15% P2O5, and 15% K2O. The calcium fertilizer is CaCl2. The conditions for seedling cultivation were as follows: LED light source was used, with a spectral composition of 31% quanta in the 400-499nm range, 11% in the 500-599nm range, 56% in the 600-700nm range, and 2% in the 701-780nm range; the illumination duration was 8 hours per day, and the light intensity was 100 μmol·m⁻². -2 ·s -1 The ambient temperature was controlled at 28℃, and the relative humidity at 85%. The salinity of the substrate was monitored regularly using a salinity meter and adjusted with sea salt solution to maintain the salinity at 15‰. The substrate was watered regularly every day to keep it moist but not waterlogged. Seedlings harvested after 90 days of cultivation were considered mature seedlings, and their various indicators were measured.

[0029] Figure 3 The effects of different calcium fertilizer application rates on the growth of *Rhizophora stylosa* seedlings. Figure 3It can be seen that the increases in plant height, number of leaves, leaf length, and leaf width of *Rhizophora stylosa* generally show a trend of first increasing and then decreasing with the increase of calcium fertilizer application, reaching the maximum value when the calcium fertilizer application concentration is 1 times the normal concentration, with values ​​of 4.59±0.22 cm / plant, 3.58±0.31 leaves / plant, 0.41±0.03 cm / leaf, and 0.33±0.02 cm / leaf, respectively. Therefore, applying 1 times the normal calcium fertilizer concentration best promotes the overall growth performance of *Rhizophora stylosa* seedlings. Example 3: Screening of medium-dose magnesium fertilizer application in the cultivation of red olive seedlings

[0030] (1) Seed pretreatment: Same as in Example 1.

[0031] (2) Seed germination: Same as in Example 1.

[0032] (3) Seedling cultivation: When the seeds of *Rhizophora stylosa* germinate and grow 2-4 true leaves, select healthy seedlings with uniform growth and place them, along with their seedling bags, back into the intelligent greenhouse for seedling cultivation. During this period, different fertilization treatments are set as follows: compound fertilizer, calcium fertilizer, and magnesium fertilizer are applied every 20 days. The application amount of compound fertilizer is set at 1.2 g / kg each time, the application amount of calcium fertilizer is set at 0.555 g / kg each time, and the application amount of magnesium fertilizer is set at 0, 0.5, 1, 2, and 3 times the concentration (1 times the concentration is 0.612 g / kg of cultivation substrate). The effective components in the compound fertilizer are: 15% N, 15% P2O5, and 15% K2O. The calcium fertilizer is CaCl2. The magnesium fertilizer is MgSO4·7H2O. The conditions for seedling cultivation were as follows: LED light source was used, with a spectral composition of 31% quanta in the 400-499nm range, 11% in the 500-599nm range, 56% in the 600-700nm range, and 2% in the 701-780nm range; the illumination duration was 8 hours per day, and the light intensity was 100 μmol·m⁻². -2 ·s -1 The ambient temperature was controlled at 28℃, and the relative humidity at 85%. The salinity of the substrate was monitored regularly using a salinity meter and adjusted with sea salt solution to maintain the salinity at 15‰. The substrate was watered regularly every day to keep it moist but not waterlogged. Seedlings harvested after 90 days of cultivation were considered mature seedlings, and their various indicators were measured.

[0033] Figure 4 The effects of different magnesium fertilizer application rates on the growth of *Rhizophora stylosa* seedlings. Figure 4It can be seen that the increases in plant height, number of leaves, leaf length, and leaf width of *Rhizophora stylosa* generally showed a trend of first increasing, then decreasing, and then increasing again with the increase of magnesium fertilizer application. The maximum values ​​were achieved at a magnesium fertilizer concentration of 0.5 times the standard concentration, with values ​​of 6.27±1.11 cm / plant, 3.78±0.62 leaves / plant, 10.24±0.29 cm / leaf, and 4.48±0.14 cm / leaf, respectively. Therefore, a magnesium fertilizer application concentration of 0.5 times the standard concentration best promoted the overall growth performance of *Rhizophora stylosa* seedlings.

[0034] In summary, the screening of compound fertilizer, calcium fertilizer, and magnesium fertilizer application rates during seedling cultivation shows that the seedlings exhibited good growth when the compound fertilizer application rate was 1.2 g / kg, the calcium fertilizer application rate was 1 times, and the magnesium fertilizer application rate was 0.5 times. All key growth parameters reached optimal levels, providing favorable growth support for the cultivation and development of red olive seedlings.

[0035] 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 indoor seedling cultivation of the mangrove plant *Rhizophora stylosa*, characterized in that: Includes the following steps: (1) Seed pretreatment: Rinse the red olive seeds with clean water to remove surface impurities and dirt; The seeds were then soaked in a 1 g / L carbendazim solution for 15 minutes for disinfection. After disinfection, they were rinsed with clean water to obtain pretreated red olive seeds. (2) Seed germination: The pretreated red olive seeds are planted into seedling bags filled with culture substrate, leaving a 2cm gap between the bottom of the red olive seeds and the bottom of the seedling bag. After watering thoroughly, the seeds are placed in a smart greenhouse for germination and cultivation. The culture substrate is formulated by weight ratio as humus: sand: loess = 1:3:

3. (3) Seedling cultivation: When the seeds of red sea olive germinate and grow 2-4 true leaves, select healthy seedlings with uniform growth, and place them together with the seedling bags in the intelligent greenhouse for seedling cultivation. The seedlings will be harvested after 90 days. The conditions for germination cultivation in step (2) are as follows: ① Illumination conditions: LED light source is used, with a spectral composition of 31% photons in the 400-499nm range, 11% in the 500-599nm range, 56% in the 600-700nm range, and 2% in the 701-780nm range. The illuminance is 200-300 μmol·m. -2 ·s -1 Light duration 6 hours / day; ② Ambient temperature and humidity: The ambient temperature should be controlled at 26~28℃, and the relative humidity should be controlled at 70%~90%; ③ Water management: Water regularly every day to keep the growing medium moist but not waterlogged; The conditions for seedling cultivation in step (3) are as follows: ① Illumination conditions: LED light source is used, with a spectral composition of 31% photons in the 400-499nm range, 11% in the 500-599nm range, 56% in the 600-700nm range, and 2% in the 701-780nm range. The illuminance is 100-200 μmol·m. -2 ·s -1 Light exposure duration: 8 hours / day; ② Ambient temperature and humidity: The ambient temperature should be controlled at 28~30℃, and the relative humidity should be controlled at 70%~90%; ③ Water management: Water regularly every day to keep the growing medium moist but not waterlogged; ④ Nutritional supply: Fertilize once every 20 days; ⑤ Substrate salinity: The salinity of the culture substrate should be controlled at 15‰.

2. The indoor seedling raising method according to claim 1, characterized in that: The amount of fertilizer supplied in step (3) is calculated per kg of cultivation substrate as follows: compound fertilizer 0.2~1.2g, calcium fertilizer 0.278~1.665g, and magnesium fertilizer 0.308~1.849g.

3. The indoor seedling raising method according to claim 2, characterized in that: The effective components of the compound fertilizer are N 15%, P2O5 15%, and K2O 15%.

4. The indoor seedling raising method according to claim 2, characterized in that: The calcium fertilizer mentioned is CaCl2.

5. The indoor seedling raising method according to claim 2, characterized in that: The magnesium fertilizer is MgSO4·7H2O.

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