Method and system for regulating and controlling dynamic light environment in whole growth period of lettuce in plant factory

Abstract

The invention relates to a plant factory lettuce whole-growth-period dynamic light environment regulation and control method. The method comprises the steps that whole-growth-period staged light environment parameters are designed; building plant growth parameters in different development stages; a matched intelligent regulation and control system is built by using the whole growth period staged light environment parameters, the plant growth parameters in different development stages, the GA-BP neural network and the dynamic fine adjustment rule, the dynamic fine adjustment rule is set, the current light environment is finely adjusted, and a more balanced regulation and control scheme is obtained. Compared with traditional constant red and blue light, four-stage dynamic regulation and control has the advantages that the light energy utilization rate is increased by 27.3%, the energy consumption of artificial light is reduced by 20.1%, and the problem of high energy consumption in the background technology is solved; according to the same test data, the fresh weight of a single plant of the Italian lettuce treated by the method is 45.2 g, and is improved by 17.4% compared with 38.5 g regulated by single-stage far-red light; the content of soluble sugar is 3.2%, the content of VC is 26.5 mg / 100g and is respectively increased by 14.3% and 12.3%, and the yield and the quality are both excellent.

Description

Technical Field

[0001] This invention relates to the field of dynamic light environment regulation technology for lettuce throughout its entire growth period in plant factories, and in particular to a method and system for dynamic light environment regulation of lettuce throughout its entire growth period in plant factories. Background Technology

[0002] Currently, existing technologies for dynamic light environment control of lettuce throughout its entire growth period in plant factories include single-stage far-red light control technology and constant red-blue light control technology.

[0003] Single-stage far-red light regulation technology refers to the use of fixed red or far-red light treatment for lettuce seedlings in plant factories. This aims to improve seedling resistance by promoting root development. However, it only covers the seedling stage and does not address the optimization of light parameters during the rapid growth and maturity stages. Furthermore, it lacks a dynamic fine-tuning mechanism, leading to wasted light energy later on. For example, optimizing red light only during the seedling stage (far-red light = 1.6 light quality) fails to cover the rapid growth and maturity stages. The rapid growth stage requires high-photosynthetic-efficiency light formulations (such as red and blue light) to promote carbon assimilation, while the maturity stage requires UV-A to improve quality. This technology continues to use seedling-stage light parameters in the later stages, resulting in wasted light energy and insufficient photosynthetic efficiency, failing to achieve a synergistic improvement in both yield and quality.

[0004] Constant red-blue light regulation technology refers to using a fixed light environment throughout the entire growth period, relying on human experience to set parameters without incorporating real-time physiological indicators such as stomatal conductance and photosynthetic rate for adjustment. This results in an inability to adapt to the light requirements of different stages and low light energy utilization. A fixed red-to-blue light ratio of 3:1 and a fixed light intensity throughout the entire growth period, without considering real-time physiological indicators, leads to problems. Excessive light intensity during the seedling stage can cause seedling stress, while failure to reduce light intensity during maturity can accelerate premature aging. Furthermore, the lack of a dynamic fine-tuning mechanism makes it impossible to adapt to the differences in light requirements at different stages, resulting in low light energy utilization and high energy consumption. Summary of the Invention

[0005] To address the problem that existing light regulation strategies, which mainly rely on crop photosynthesis models to obtain target values, cannot meet the needs of carbon assimilation during rapid growth and quality improvement during maturity, nor can they adapt to the light requirements at different stages, the present invention aims to provide a dynamic light environment regulation method for lettuce throughout its entire growth period in a plant factory. This method offers advantages in light energy utilization and energy consumption, synergistic improvement in yield and quality, and features high regulation precision and stability.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a method for dynamic light environment regulation of lettuce throughout its entire growth period in a plant factory, the method comprising the following sequential steps:

[0007] (1) Design light environment parameters for the entire growth period in stages: including light environment parameters for the seedling stage, seedling stage, rapid growth stage and maturity stage. The light environment parameters include time range, light quality parameters, light intensity parameters, photoperiod, supporting environmental parameters and core control targets;

[0008] (2) Based on the light environment parameters of the whole growth period, construct plant growth parameters for different developmental stages;

[0009] (3) By using the light environment parameters of the whole growth period, the plant growth parameters of different development stages, the GA-BP neural network and the dynamic fine-tuning rules, a supporting intelligent control system is built, and the dynamic fine-tuning rules are set to fine-tune the current light environment to obtain a more balanced control scheme.

[0010] In step (1), the seedling stage is from sowing to 14 days before transplanting; the light quality parameter is LED white light; and the light intensity parameter is 200±30 μmol·m. -2 ·s -1 The photoperiod is 16 hours of irradiation followed by 8 hours of extinguishing; the supporting environmental parameters include a daytime temperature of 26℃ and a nighttime temperature of 24℃, a relative humidity of 60% to 70%, and a Hogland nutrient solution of 1:1; the core control objective is to promote seed germination and seedling uniformity, ensuring that the seedlings reach the standard of having two true leaves fully expanded at the time of transplanting.

[0011] In step (1), during the seedling stage, the time range is 1 to 8 days after transplanting; the light quality parameter is to supplement far-red light with white light to control the light quality ratio R:FR of red light to far-red light at 1.6; the light intensity parameter is 150 μmol·m -2 ·s -1 The photocycle consists of 16 hours of irradiation followed by 8 hours of extinguishing; the supporting environmental parameters include a daytime temperature of 26℃ and a nighttime temperature of 24℃, a relative humidity of 60% to 70%, and a Hogland nutrient solution circulation frequency of 2 times per day; the core regulatory objective is to improve root fresh weight and stomatal conductance, laying the foundation for subsequent growth.

[0012] In step (1), during the rapid growth period, the time range is 9 to 23 days after transplanting; the light quality parameter is that the light quality ratio of red light to blue light (R:B) is controlled at 3:1; the light intensity parameter is 200 μmol·m -2 ·s -1 The photoperiod is 16 hours of irradiation followed by 8 hours of extinguishing; the supporting environmental parameters include a daytime temperature of 26°C and a nighttime temperature of 24°C, a relative humidity of 65% to 75%, and a conductivity of 2.0 to 2.2 mS / cm for Hogland 1x nutrient solution; the core regulatory objective is to improve canopy photosynthetic efficiency and promote leaf expansion and dry matter accumulation.

[0013] In step (1), during the ripening period, the time range is 24 to 28 days after transplanting; the light quality parameters are that the light quality ratio of red light to blue light (R:B) is controlled at 3:1, and 20 μmol·m -2 ·s -1 Ultraviolet light; light intensity parameter is 150 μmol·m -2 ·s-1 The photocycle consists of 16 hours of irradiation followed by 8 hours of extinguishing; the supporting environmental parameters include a daytime temperature of 26°C and a nighttime temperature of 24°C, a relative humidity of 65% to 75%, and a pH value of Hogland 1x nutrient solution adjusted to 6.5 to 7.0; the core regulatory objective is to increase the content of soluble sugars and vitamin C, and delay premature aging of the plants.

[0014] In step (2), the plant growth parameters at different developmental stages specifically refer to:

[0015] During the seedling stage: the seedlings are 5 to 6 cm tall and have 2 true leaves fully expanded, for 1 day;

[0016] During the seedling to rapid growth stage: plant height ≥ 8 cm and stomatal conductance Gs stable ≥ 200 mmol·m -2 ·s -1 It lasted for 2 days;

[0017] During the rapid growth to maturity stage: the canopy projection area is ≥150 cm² / plant and the leaf area index (LAI) is ≥2.0 for 3 consecutive days.

[0018] Step (3) specifically includes the following steps:

[0019] (3a) Data preprocessing: The data on growth days, light intensity, light quality, stomatal conductance, photosynthetic rate, and light energy utilization rate were normalized to the [0,1] interval using the Min-max scaling method. In the formula, y represents the original data. The data is after normalization; The minimum value of the original data. The maximum value of the original data;

[0020] (3b) Model Training: A GA-BP neural network was used. The input layer had two nodes: post-transplantation days (DAP) and light intensity (PPFD). The output layer had two nodes: photosynthetic rate (A) and light energy utilization efficiency (LUE). The number of hidden layer nodes was calculated using the formula Nm = (Ni + No) + Determine, in the formula, Ni represents the number of hidden layer neurons in the initial attempt, and No represents the number of neurons in the input layer and No represents the number of neurons in the output layer. For adjustment coefficients, [0, 10]; The initial weights and thresholds are optimized using a genetic algorithm to ensure that the model fit R² ≥ 0.92;

[0021] (3c) Set dynamic fine-tuning rules: Collect measured data every 2 hours and compare it with the model prediction. If the deviation is >10%, adjust according to the following logic:

[0022] If the measured photosynthetic rate A is less than the predicted value: increase the proportion of red light by 5% or increase the light intensity by 20 μmol·m -2 ·s -1 ;

[0023] If the measured light energy utilization rate (LUE) is less than the predicted value, reduce the light intensity by 10% or shorten the photoperiod to 15 hours of illumination followed by 9 hours of extinguishing to reduce ineffective energy consumption.

[0024] Another object of the present invention is to provide a system for dynamic light environment regulation of lettuce throughout its entire growth period in a plant factory, comprising:

[0025] The monitoring module includes the LI-6800 portable photosynthesis measurement system, plant phenotyping system, and stomatal observer; the monitoring module transmits monitoring data to the control module in real time via a 4G wireless module, ensuring data latency <10s;

[0026] The control module uses an STM32F407 embedded microcontroller with a built-in GA-BP neural network. It has stage switching logic and data storage functions. It can receive monitoring data, run the model to calculate the optimal optical parameters, and output control instructions to the execution module. It also supports local data storage and remote export.

[0027] The execution module employs a dimmable LED array as its light source. This dimmable LED array includes red light at 660nm, blue light at 450nm, far-red light at 730nm, and UV-A at 405nm, with a single-band intensity adjustment accuracy of ±5μmol·m. -2 ·s -1 It is driven by the PWM signal output by the control module; the supporting equipment includes a nutrient solution circulation pump and a temperature and humidity controller.

[0028] As can be seen from the above technical solution, the beneficial effects of the present invention are as follows: First, it has advantages in light energy utilization and energy consumption: Compared with traditional constant red and blue light, the four-stage dynamic regulation of the present invention improves light energy utilization by 27.3% and reduces artificial light energy consumption by 20.1%, solving the problem of high energy consumption in the background technology; Second, it synergistically improves yield and quality: According to the same experimental data, the fresh weight of Italian raw plantlets treated by the present invention is 45.2g, which is 17.4% higher than the 38.5g controlled by single-stage far-red light; soluble sugar is 3.2% and VC is 26.5mg / 100g, which are improved by 14.3% and 12.3% respectively, achieving both superior yield and quality; Third, it has high regulation precision and stability: Combined with GA-BP neural network (R²≥0.92), the light parameters are dynamically fine-tuned every 2 hours, with a light intensity adjustment precision of ±5μmol·m -2 ·s -1Compared with the background technology of artificial experience-based regulation, the deviation of photosynthetic rate was controlled within 10%, avoiding seedling stress and premature aging at maturity. The experiment was repeated 3 times, and the data variation coefficient was ≤5%, showing significant stability. Attached Figure Description

[0029] Figure 1 This is a flowchart of the method of the present invention. Detailed Implementation

[0030] like Figure 1 As shown, a method for dynamic light environment regulation of lettuce throughout its entire growth period in a plant factory is described. This method includes the following sequential steps:

[0031] (1) Design light environment parameters for the entire growth period in stages: including light environment parameters for the seedling stage, seedling stage, rapid growth stage and maturity stage. The light environment parameters include time range, light quality parameters, light intensity parameters, photoperiod, supporting environmental parameters and core control targets;

[0032] (2) Based on the light environment parameters of the whole growth period, construct plant growth parameters for different developmental stages;

[0033] (3) By using the light environment parameters of the whole growth period, the plant growth parameters of different development stages, the GA-BP neural network and the dynamic fine-tuning rules, a supporting intelligent control system is built, and the dynamic fine-tuning rules are set to fine-tune the current light environment to obtain a more balanced control scheme.

[0034] In step (1), the seedling stage is from sowing to 14 days before transplanting; the light quality parameter is LED white light; and the light intensity parameter is 200±30 μmol·m. -2 ·s -1 The photoperiod is 16 hours of irradiation followed by 8 hours of extinguishing; the supporting environmental parameters include a daytime temperature of 26℃ and a nighttime temperature of 24℃, a relative humidity of 60% to 70%, and a Hogland nutrient solution of 1:1; the core control objective is to promote seed germination and seedling uniformity, ensuring that the seedlings reach the standard of having two true leaves fully expanded at the time of transplanting.

[0035] In step (1), during the seedling stage, the time range is 1 to 8 days after transplanting; the light quality parameter is to supplement far-red light with white light to control the light quality ratio R:FR of red light to far-red light at 1.6; the light intensity parameter is 150 μmol·m -2 ·s -1 The photocycle consists of 16 hours of irradiation followed by 8 hours of extinguishing; the supporting environmental parameters include a daytime temperature of 26℃ and a nighttime temperature of 24℃, a relative humidity of 60% to 70%, and a Hogland nutrient solution circulation frequency of 2 times per day; the core regulatory objective is to improve root fresh weight and stomatal conductance, laying the foundation for subsequent growth.

[0036] In step (1), during the rapid growth period, the time range is 9 to 23 days after transplanting; the light quality parameter is that the light quality ratio of red light to blue light (R:B) is controlled at 3:1; the light intensity parameter is 200 μmol·m -2 ·s -1 The photoperiod is 16 hours of irradiation followed by 8 hours of extinguishing; the supporting environmental parameters include a daytime temperature of 26°C and a nighttime temperature of 24°C, a relative humidity of 65% to 75%, and a conductivity of 2.0 to 2.2 mS / cm for Hogland 1x nutrient solution; the core regulatory objective is to improve canopy photosynthetic efficiency and promote leaf expansion and dry matter accumulation.

[0037] In step (1), during the ripening period, the time range is 24 to 28 days after transplanting; the light quality parameters are that the light quality ratio of red light to blue light (R:B) is controlled at 3:1, and 20 μmol·m -2 ·s -1 Ultraviolet light; light intensity parameter is 150 μmol·m -2 ·s -1 The photocycle consists of 16 hours of irradiation followed by 8 hours of extinguishing; the supporting environmental parameters include a daytime temperature of 26°C and a nighttime temperature of 24°C, a relative humidity of 65% to 75%, and a pH value of Hogland 1x nutrient solution adjusted to 6.5 to 7.0; the core regulatory objective is to increase the content of soluble sugars and vitamin C, and delay premature aging of the plants.

[0038] In step (2), the plant growth parameters at different developmental stages specifically refer to:

[0039] During the seedling stage: the seedlings are 5 to 6 cm tall and have 2 true leaves fully expanded, for 1 day;

[0040] During the seedling to rapid growth stage: plant height ≥ 8 cm and stomatal conductance Gs stable ≥ 200 mmol·m -2 ·s -1 It lasted for 2 days;

[0041] During the rapid growth to maturity stage: the canopy projection area is ≥150 cm² / plant and the leaf area index (LAI) is ≥2.0 for 3 consecutive days.

[0042] Step (3) specifically includes the following steps:

[0043] (3a) Data preprocessing: The data on growth days, light intensity, light quality, stomatal conductance, photosynthetic rate, and light energy utilization rate were normalized to the [0,1] interval using the Min-max scaling method. In the formula, y represents the original data. The data is after normalization; The minimum value of the original data. The maximum value of the original data;

[0044] (3b) Model Training: A GA-BP neural network was used. The input layer had two nodes: post-transplantation days (DAP) and light intensity (PPFD). The output layer had two nodes: photosynthetic rate (A) and light energy utilization efficiency (LUE). The number of hidden layer nodes was calculated using the formula Nm = (Ni + No) + Determine, in the formula, Ni represents the number of hidden layer neurons in the initial attempt, and No represents the number of neurons in the input layer and No represents the number of neurons in the output layer. For adjustment coefficients, [0, 10]; The initial weights and thresholds are optimized using a genetic algorithm to ensure that the model fit R² ≥ 0.92;

[0045] (3c) Set dynamic fine-tuning rules: Collect measured data every 2 hours and compare it with the model prediction. If the deviation is >10%, adjust according to the following logic:

[0046] If the measured photosynthetic rate A is less than the predicted value: increase the proportion of red light by 5% or increase the light intensity by 20 μmol·m -2 ·s -1 ;

[0047] If the measured light energy utilization rate (LUE) is less than the predicted value, reduce the light intensity by 10% or shorten the photoperiod to 15 hours of illumination followed by 9 hours of extinguishing to reduce ineffective energy consumption.

[0048] The following combination Figure 1 The present invention will be further described below.

[0049] The work process is based on the entire growth cycle of one head of "Italian lettuce":

[0050] 1. Seedling stage (1-14 days): After disinfection and germination, the seeds are sown on sponge blocks and placed under LED white light for cultivation. The germination rate is monitored daily. After the seeds reach the standard of 2 true leaves on the 14th day, they are transplanted to hydroponic racks.

[0051] 2. Seedling stage (15-22 days, 1-8 days after transplanting): The system automatically switches to R / FR=1.6 light quality and 150 μmol·m⁻²·m⁻²·d⁻¹. -2 ·s -1 Light intensity: Gs is monitored every 2 hours by LI-6800. The stage switch is triggered after the target is reached on the 22nd day (8 days after transplanting).

[0052] 3. Rapid growth period (23-37 days, 9-23 days after transplanting): Switch to R / B=3:1 light quality and 200μmol·m⁻² ... -2 ·s -1 Light intensity is monitored daily using a plant phenotyping system to measure canopy parameters, and the GA-BP neural network fine-tunes light parameters every 2 hours to ensure a photosynthetic rate A ≥ 18 μmol·m⁻¹.-2 ·s -1 ;

[0053] 4. Maturity period (38-42 days, 24-28 days after transplanting): Add UV-A light quality, continuously monitor soluble sugar and VC content, and issue a harvest reminder after the target is reached on the 42nd day to complete the full cycle regulation.

[0054] Variety compatibility replacement: The original plan was designed for Italian lettuce, but it can be extended to varieties such as glass lettuce and Rosa Red, by adjusting the light quality ratio to achieve compatibility.

[0055] Glass lettuce (thin leaves, low photosynthetic efficiency): During the seedling stage, the R / FR ratio is adjusted from 1.6 to 1.8-2.0, and during the rapid growth period, the R / B ratio is adjusted from 3:1 to 2.5:1. Increasing the proportion of blue light enhances the activity of the photosynthetic system, which can increase the fresh weight of a single plant by 12%-15%.

[0056] Rosa Red (high anthocyanin content): UV-A light intensity at maturity decreases from 20 μmol·m -2 ·s -1 Increased to 25-30 μmol·m -2 ·s -1 The anthocyanin content can be increased by an additional 8%-10%, taking into account both color and nutritional quality.

[0057] Light intensity and photoperiod range expanded: The original scheme had a light intensity range of 150-200 μmol·m. -2 ·s -1 It can be extended to 120-350 μmol·m -2 ·s -1 Adaptable to different seasonal energy consumption needs:

[0058] Winter (high electricity prices): Use low light intensity range (120-180 μmol·m⁻²) -2 ·s -1 With the photoperiod extended to 17h / 7h, energy consumption is reduced by 18%, while output decreases by only 5%.

[0059] Summer (low electricity price): Use high light intensity range (300-350 μmol·m⁻¹) -2 ·s -1 This shortens the photoperiod to 14h / 10h, reduces the growth cycle from 29 days to 25 days, and increases annual production capacity by 13%.

[0060] Nutrient solution and cultivation substrate materials expansion:

[0061] Nutrient solution formula replacement: The original formula uses Hoagland's 1x nutrient solution, which can be replaced with a Japanese garden trial formula or a Yamazaki lettuce-specific formula:

[0062] Japanese garden trial formula (NPK ratio 1:0.5:1.2): Increases soluble sugar content in lettuce by 7%-9%, suitable for high-quality oriented production;

[0063] Yamazaki lettuce-specific formula (optimized calcium and magnesium content): The incidence of leaf burn decreased from 3% to 0.5%, and the marketability increased by 2.5 percentage points.

[0064] Cultivation substrate expansion: The original plan used hydroponic sponge blocks, which can be replaced with rock wool substrate or coconut coir substrate.

[0065] Rock wool matrix (bulk density 80-100 kg / m³): water retention is improved by 30%, nutrient solution circulation frequency is reduced (from 2 times / day to 1 time / day), and energy consumption is reduced by 15%;

[0066] Coconut coir substrate (EC≤1.0mS / cm): Rich in organic matter, it can promote the colonization of root microorganisms, increase the fresh weight of roots by 10%-12%, and enhance stress resistance.

[0067] Crop type expansion:

[0068] The original solution was designed for lettuce, but it can be extended to other leafy vegetables by adjusting the light environment parameters.

[0069] Bok choy: During the seedling stage, the light quality is adjusted to R / B=2:1 (increasing the proportion of blue light) to inhibit excessive growth, and the plant height is controlled at 15-18cm (commercial plant height). The growth cycle is shortened from 29 days to 22 days.

[0070] Spinach: Supplement with 5 μmol·m during the ripening period -2 ·s -1 UV-B (310nm) increases carotenoid content by 15%-18% without affecting leaf palatability, expanding the production scenarios for functional vegetables.

[0071] In summary, this invention offers advantages in light energy utilization and energy consumption: compared to traditional constant red and blue light, the four-stage dynamic regulation of this invention improves light energy utilization by 27.3% and reduces artificial light energy consumption by 20.1%, solving the high energy consumption problem of the prior art. It also synergistically improves yield and quality: according to the same experimental data, the fresh weight of Italian raw plantlets treated with this invention was 45.2g, an increase of 17.4% compared to 38.5g under single-stage far-red light regulation; soluble sugar content was 3.2%, and vitamin C was 26.5mg / 100g, representing increases of 14.3% and 12.3% respectively, achieving superior yield and quality. Furthermore, it boasts high regulation precision and stability: combined with a GA-BP neural network (R²≥0.92), the light parameters are dynamically fine-tuned every 2 hours, with a light intensity adjustment precision of ±5μmol·m⁻¹. -2 ·s -1Compared with the background technology of artificial experience-based regulation, the deviation of photosynthetic rate was controlled within 10%, avoiding seedling stress and premature aging at maturity. The experiment was repeated 3 times, and the data variation coefficient was ≤5%, showing significant stability.

[0072] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed invention. The scope of protection claimed by the appended claims and their equivalents is defined.

Claims

1. A method for dynamic light environment regulation of lettuce throughout its entire growth period in a plant factory, characterized by: The method includes the following steps in sequence: (1) Design light environment parameters for the entire growth period in stages: including light environment parameters for the seedling stage, seedling stage, rapid growth stage and maturity stage. The light environment parameters include time range, light quality parameters, light intensity parameters, photoperiod, supporting environmental parameters and core control targets; (2) Based on the light environment parameters of the whole growth period, construct plant growth parameters for different developmental stages; (3) By using the light environment parameters of the whole growth period, the plant growth parameters of different development stages, the GA-BP neural network and the dynamic fine-tuning rules, a supporting intelligent control system is built, and the dynamic fine-tuning rules are set to fine-tune the current light environment to obtain a more balanced control scheme.

2. The method for dynamic light environment regulation of lettuce throughout its entire growth period in a plant factory, as described in claim 1, is characterized in that: In step (1), during the seedling stage, the time range is 14 days before transplanting; the light quality parameter is LED white light; the light intensity parameter is 200±30 μmol·m -2 ·s -1 ; the photoperiod is 16 hours of illumination and 8 hours of darkness; the supporting environmental parameters include a daytime temperature of 26°C, a nighttime temperature of 24°C, a relative humidity of 60% to 70%, and Hoagland 1 times of nutrient solution; and the core regulation target is to promote seed germination and seedling uniformity and to ensure that 2 true leaves are flat at the time of transplanting.

3. The method for dynamic light environment regulation of lettuce throughout its entire growth period in a plant factory, as described in claim 1, is characterized in that: In step (1), in the seedling stage, the time range is 1-8 days after transplanting; the light quality parameter is to supplement far-red light on the basis of white light to control the light quality ratio R:FR of red and far-red light bands to 1.6; the light intensity parameter is 150 μmol·m -2 ·s -1 ; the photoperiod is 16 hours of irradiation and 8 hours of extinction; the matching environment parameters include daytime temperature 26°C, nighttime temperature 24°C, relative humidity 60%-70%, and Hoggland 1-time nutrient solution circulation frequency 2 times / day; the core regulation target is to improve root fresh weight and stomatal conductance to lay a foundation for subsequent growth.

4. The method for dynamic light environment regulation of lettuce throughout its entire growth period in a plant factory, as described in claim 1, is characterized in that: In step (1), in the rapid growth period, the time range is 9 to 23 days after transplanting; the light quality parameter is to control the light quality ratio R:B of the red light band light and the blue light band light at 3:1; the light intensity parameter is 200 μmol·m -2 ·s -1 ; the photoperiod is 16 hours of irradiation and 8 hours of extinction; the matching environment parameters include day temperature 26℃ and night temperature 24℃, relative humidity 65% to 75%, and the conductivity of Hoggan 1 times of nutrient solution is maintained at 2.0 to 2.2 mS / cm; the core regulation target is to improve the canopy photosynthetic efficiency, promote leaf expansion and dry matter accumulation.

5. The method for dynamic light environment regulation of lettuce throughout its entire growth period in a plant factory, as described in claim 1, is characterized in that: In step (1), during the ripening period, the time range is 24 to 28 days after transplanting; the light quality parameters are that the light quality ratio of red light to blue light (R:B) is controlled at 3:1, and 20 μmol·m -2 ·s -1 Ultraviolet light; light intensity parameter is 150 μmol·m -2 ·s -1 The photocycle consists of 16 hours of irradiation followed by 8 hours of extinguishing; the supporting environmental parameters include a daytime temperature of 26°C and a nighttime temperature of 24°C, a relative humidity of 65% to 75%, and a pH value of Hogland 1x nutrient solution adjusted to 6.5 to 7.0; the core regulatory objective is to increase the content of soluble sugars and vitamin C, and delay premature aging of the plants.

6. The method for dynamic light environment regulation of lettuce throughout its entire growth period in a plant factory, as described in claim 1, is characterized in that: In step (2), the plant growth parameters at different developmental stages specifically refer to: During the seedling stage: the seedlings are 5 to 6 cm tall and have 2 true leaves fully expanded, for 1 day; During the seedling to rapid growth stage: plant height ≥8cm and stomatal conductance Gs stable ≥200 mmol·m -2 ·s -1 It lasted for 2 days; During the rapid growth to maturity stage: the canopy projection area is ≥150 cm² / plant and the leaf area index (LAI) is ≥2.0 for 3 consecutive days.

7. The method for dynamic light environment regulation of lettuce throughout its entire growth period in a plant factory, as described in claim 1, is characterized in that: Step (3) specifically includes the following steps: (3a) Data preprocessing: The data on growth days, light intensity, light quality, stomatal conductance, photosynthetic rate, and light energy utilization rate were normalized to the [0,1] interval using the Min-max scaling method. In the formula, y represents the original data. The data is after normalization; The minimum value of the original data. The maximum value of the original data; (3b) Model Training: A GA-BP neural network was used. The input layer had two nodes: post-transplantation days (DAP) and light intensity (PPFD). The output layer had two nodes: photosynthetic rate (A) and light energy utilization efficiency (LUE). The number of hidden layer nodes was calculated using the formula Nm = (Ni + No) + Determine, in the formula, Ni represents the number of hidden layer neurons in the initial attempt, and No represents the number of neurons in the input layer and No represents the number of neurons in the output layer. For adjustment coefficients, [0, 10]; The initial weights and thresholds are optimized using a genetic algorithm to ensure that the model fit R² ≥ 0.92; (3c) Set dynamic fine-tuning rules: Collect measured data every 2 hours and compare it with the model prediction. If the deviation is >10%, adjust according to the following logic: If the measured photosynthetic rate A is less than the predicted value: increase the proportion of red light by 5% or increase the light intensity by 20 μmol·m⁻². -2 ·s -1 ; If the measured light energy utilization rate (LUE) is less than the predicted value, reduce the light intensity by 10% or shorten the photoperiod to 15 hours of illumination followed by 9 hours of extinguishing to reduce ineffective energy consumption.

8. A system for implementing the dynamic light environment control method for the entire growth period of lettuce in a plant factory according to any one of claims 1 to 7, characterized in that: include: The monitoring module includes the LI-6800 portable photosynthesis measurement system, plant phenotyping system, and stomatal observation instrument; The monitoring module transmits monitoring data to the control module in real time via a 4G wireless module, ensuring a data delay of <10s; The control module uses an STM32F407 embedded microcontroller with a built-in GA-BP neural network. It has stage switching logic and data storage functions. It can receive monitoring data, run the model to calculate the optimal optical parameters, and output control instructions to the execution module. It also supports local data storage and remote export. The execution module employs a dimmable LED array as its light source. This dimmable LED array includes red light at 660nm, blue light at 450nm, far-red light at 730nm, and UV-A at 405nm, with a single-band light intensity adjustment accuracy of ±5μmol·m⁻¹. -2 ·s -1 It is driven by the PWM signal output by the control module; the supporting equipment includes a nutrient solution circulation pump and a temperature and humidity controller.

Images