Cotton one-film six-row wide-narrow-row close planting and staggered planting method

Abstract

The invention discloses a one-film six-row wide-narrow-row close-planting staggered planting method for cotton, which comprises the following steps: measuring the soil nutrient content of a region to be planted, calculating the comprehensive score of soil fertility, selecting a basic plant spacing according to the tillering coefficient of a cotton variety, fitting an accumulated temperature correction function, calculating a predicted value of the tillering rate, and calculating a dynamic offset in combination with the latitude of a planting field. Determining a narrow row spacing and a sowing depth according to the dynamic offset, extracting a growth picture of the same variety of cotton in the same region after the flowering and boll-setting period, extracting a planting row spacing mean value of the canopy coverage in a preset range as a wide row spacing, planting cotton according to the basic plant spacing, the narrow row spacing, the wide row spacing and the sowing depth, and monitoring the canopy photosynthetically active radiation in real time. And dynamically regulating and controlling a drip irrigation fertilization strategy according to the photosynthetically active radiation of the canopy. By means of the method, the photosynthetic efficiency, the water and fertilizer utilization efficiency and the stress resistance of cotton groups can be improved, a brand new technical path is provided for high-yield and high-quality cultivation of cotton, and the method has important significance in promoting intelligent transformation of the cotton planting industry.

Description

A cotton planting method with six rows of wide and narrow rows, dense planting and staggered planting under one film. Technical Field

[0001] This invention relates to the field of agricultural planting technology, and in particular to a method for planting cotton in six rows with wide and narrow rows with staggered planting under one film. Background Technology

[0002] Cotton is an important economic crop in my country. Its yield and quality directly affect the supply of raw materials for the textile industry and farmers' income. In the cotton planting industry, dense planting is a key technical means to increase the yield per unit area, and the combination of drip irrigation under film and wide and narrow row configuration has become the mainstream cotton planting model in arid areas.

[0003] However, current traditional cotton planting techniques have many prominent problems: First, parameters such as plant spacing and sowing depth are mostly set based on experience, without fully considering the differences in soil fertility, regional climate (such as accumulated temperature and latitude), and tillering characteristics of varieties. This results in an unreasonable plant population structure, poor ventilation and light penetration, and an increased risk of pests and diseases and lodging. Second, the fixed design of wide and narrow row spacing cannot adapt to the canopy growth needs of cotton at different growth stages, affecting the improvement of photosynthetic efficiency. Third, water and fertilizer management lacks a dynamic control mechanism. Irrigation volume and fertilization plans are mostly based on a uniform standard, without being accurately adapted to real-time growth indicators such as effective photosynthetic radiation of the canopy. This results in water waste, low fertilizer utilization, and can easily lead to ecological problems such as secondary soil salinization. Therefore, this invention proposes a method for dense, staggered planting of cotton in six rows with one film, using a combination of wide and narrow rows. The basic plant spacing is dynamically determined through a comprehensive soil fertility score. The tillering trend is predicted by accumulated temperature and early temperature and humidity, and the dynamic offset of the rows is calculated. Furthermore, the configuration of wide and narrow rows is determined by UAV image recognition. Water and fertilizer strategies are adjusted in real time throughout the entire growth period based on the effective photosynthetic radiation of the canopy. This achieves dynamic and precise management of the entire process from planting design to growth management, significantly improving the spatial rationality of the population structure, the efficiency of light and heat resource utilization, and the accuracy of water and fertilizer response. It provides a systematic technical solution for high-yield, high-quality, and high-efficiency cotton production. Summary of the Invention

[0004] The purpose of this invention is to provide a method for planting cotton in six rows with wide and narrow spacing using a single film and staggered planting.

[0005] To achieve the above objectives, the present invention is implemented according to the following technical solution: The present invention includes the following steps: measuring the soil nutrient content of the area to be planted and calculating the comprehensive soil fertility score; selecting the basic plant spacing based on the tillering coefficient of the cotton variety; inputting local historical accumulated temperature data to fit the accumulated temperature correction function, calculating the predicted value of cotton tillering rate 20 days after sowing, and calculating the dynamic offset based on the latitude of the planting site, the accumulated temperature correction function, and the predicted value of tillering rate; determining the narrow row spacing and sowing depth based on the dynamic offset; extracting growth images of cotton of the same variety in the same region after the flowering and boll-forming stage; extracting the average value of planting row spacing with canopy coverage within a preset range as the wide row spacing; planting cotton according to the basic plant spacing, narrow row spacing, wide row spacing, and sowing depth; monitoring the photosynthetically active radiation of the canopy in real time; and dynamically adjusting the drip irrigation fertilization strategy based on the photosynthetically active radiation of the canopy.

[0006] Furthermore, the method for selecting the basic plant spacing includes: determining the soil nutrient content of the area to be planted and calculating the comprehensive soil fertility score; matching the plant spacing range based on the tillering coefficient of the cotton variety and domain knowledge; and calculating the basic plant spacing based on the maximum plant spacing and the comprehensive soil fertility score, expressed as: ;in Based on the basic plant spacing, This is the plant spacing adjustment coefficient. This is the maximum plant spacing. This is a comprehensive score for soil fertility.

[0007] Furthermore, the method for calculating the dynamic offset includes: inputting local historical accumulated temperature data and fitting an accumulated temperature correction function, the expression of which is: ;in This is the accumulated temperature correction function. The effective accumulated temperature is greater than 12℃; the predicted tillering rate of cotton 20 days after sowing is calculated using the following expression: ;in The tillering rate of cotton. The average temperature 5-15 days after sowing. The average relative humidity is given 5-15 days after sowing. The dynamic offset is calculated based on the latitude of the planting site, the basic plant spacing, the accumulated temperature correction function, and the predicted tillering rate. The expression is as follows: ;in This is a dynamic offset. This is the offset adjustment factor. The tillering coefficient of cotton varieties. The latitude of the planting area, For reference latitude.

[0008] Furthermore, the method for determining the narrow row spacing and sowing depth based on the dynamic offset includes: taking the sum of the dynamic offset and the basic plant spacing as the narrow row spacing; and taking the sum of the standard sowing depth and 0.1 times the dynamic offset as the sowing depth.

[0009] Furthermore, the method for determining the wide row spacing includes: extracting growth images of cotton of the same variety from the same region after the flowering and boll-forming stage using a drone, calculating the canopy coverage in the RGB image of the growth image, extracting the cotton row spacing within a preset range of canopy coverage, and calculating the average cotton row spacing as the wide row spacing; the preset range is 80%-85%.

[0010] Furthermore, the method for dynamically regulating drip irrigation fertilization strategies includes: real-time monitoring of canopy photosynthetically active radiation (RALED), and adjusting the irrigation amount based on RLED, growth stage, and soil type, expressed as: ;in This represents the daily drip irrigation volume. Basic irrigation volume, The measured photosynthetically active radiation is located in the middle of the canopy. for The light saturation point during the reproductive period corresponds to photosynthetically active radiation. This represents the current leaf area index. for Optimal leaf area index during the growth period for Fertility adjustment coefficient, The soil texture coefficient is used as the basis for determining the topdressing strategy based on the photosynthetically active radiation of the canopy: when the photosynthetically active radiation is higher than the standard photosynthetically active radiation range, nitrate nitrogen is applied to promote photosynthetic nitrogen use efficiency; when the photosynthetically active radiation is lower than the standard photosynthetically active radiation range, potassium fertilizer is applied to enhance the lodging resistance of the stems.

[0011] The beneficial effects of this invention are as follows: This invention is a method for dense, staggered planting of cotton in six rows with wide and narrow rows under a single film. Compared with existing technologies, this invention has the following technical effects: This invention uses image recognition to extract the wide row spacing within a reasonable range of canopy coverage, and combines it with dynamic offset to form a three-dimensional layout of "wide and narrow row alternation + triangular staggered arrangement," allowing each cotton plant in the field to be positioned as if in a superior position on the edge of the row. This expands the growth space for underground roots and above-ground plants, greatly optimizes the utilization efficiency of light and heat resources and land space, significantly improves the light reception of the middle and lower leaves and the ventilation conditions between rows, which is beneficial for reducing disease occurrence and enhancing photosynthesis. This invention dynamically calculates the basic plant spacing and row spacing offset using multi-source information such as soil fertility scores, historical accumulated temperature, and early meteorological data. The invention, by adjusting the amount of planting and the sowing depth, breaks the limitations of traditional fixed row and plant spacing, making the planting layout more aligned with actual soil fertility and climate conditions. This provides optimized space for cotton population growth and achieves dynamic matching of planting parameters and environmental conditions. Furthermore, by monitoring the effective photosynthetic radiation of the canopy and combining the light saturation point and optimal leaf area index at different growth stages, the invention dynamically calculates the daily drip irrigation amount and intelligently adjusts nitrogen and potassium topdressing strategies based on PAR levels, forming an intelligent management mechanism of "water determined by light, fertilizer adjusted according to light," significantly improving water and fertilizer utilization efficiency. All calculations in this invention are based on available soil, meteorological, and image data, and the parameter adjustment process has clear formulas and coefficient calibration methods, facilitating localized application in different cotton-growing areas and providing reliable technical support for green, high-yield, and efficient cotton production. Attached Figure Description

[0012] Figure 1 is a flowchart of the steps of a cotton planting method with six rows of wide and narrow rows and staggered planting under one film according to the present invention; Figure 2 is a schematic diagram of a cotton planting method with six rows of wide and narrow rows and staggered planting under one film according to an embodiment of the present invention. Detailed Implementation

[0013] The present invention will be further described below through specific embodiments. The illustrative embodiments and descriptions herein are used to explain the present invention, but are not intended to limit the present invention.

[0014] The present invention discloses a method for planting cotton in six rows with wide and narrow rows under a single film, comprising the following steps: As shown in Figure 1, in this embodiment, the method includes the following steps: measuring the soil nutrient content of the planting area and calculating the comprehensive soil fertility score; selecting the basic plant spacing based on the tillering coefficient of the cotton variety; inputting local historical accumulated temperature data to fit the accumulated temperature correction function, calculating the predicted value of cotton tillering rate 20 days after sowing, and calculating the dynamic offset based on the latitude of the planting area, the accumulated temperature correction function, and the predicted value of tillering rate; determining the narrow row spacing and sowing depth based on the dynamic offset; extracting growth images of cotton of the same variety in the same region after the flowering and boll-forming stage; extracting the average planting row spacing within a preset range of canopy coverage as the wide row spacing; planting cotton according to the basic plant spacing, narrow row spacing, wide row spacing, and sowing depth; monitoring the photosynthetically active radiation of the canopy in real time; and dynamically adjusting the drip irrigation fertilization strategy based on the photosynthetically active radiation of the canopy.

[0015] In this embodiment, the method for selecting the basic plant spacing includes: measuring the soil nutrient content of the area to be planted and calculating the comprehensive soil fertility score; matching the plant spacing range according to the tillering coefficient of the cotton variety and domain knowledge; and calculating the basic plant spacing based on the maximum plant spacing and the comprehensive soil fertility score, expressed as: ;in Based on the basic plant spacing, This is the plant spacing adjustment coefficient. This is the maximum plant spacing. The soil fertility was comprehensively scored. In the actual assessment, taking the compact cotton variety "Xinluzao X" planted in the Xinjiang cotton-growing area as an example, the tillering coefficient of "Xinluzao X" was 1.1 (the tillering coefficient reflects the branching ability of the plant; the larger the value, the looser the plant structure). Based on long-term field trial data, a variety tillering coefficient-plant spacing range comparison table was pre-established. The suitable plant spacing range corresponding to this tillering coefficient was 11cm to 14cm. The maximum plant spacing was taken. Before sowing, soil samples were collected from the 0-20 cm soil layer of the plot to be planted using the five-point sampling method. The following four key fertility indicators were measured: organic matter content 1.8%, available nitrogen 90 mg / kg, available phosphorus 25 mg / kg, and available potassium 50 mg / kg. The comprehensive soil fertility score was calculated using the following formula: ;in Fertility index Weight, Fertility index Actual measured value Fertility index Standard reference values ​​are typically 1.5% organic matter, 80 mg / kg available nitrogen, 20 mg / kg available phosphorus, and 120 mg / kg available potassium. When the actual value is lower than the standard value, the score for this item is set to 100. This reflects that the stronger the soil fertility, the denser the planting density (the more energy the plant roots can absorb, resulting in lower planting density). A plant spacing adjustment coefficient is used. The value is 1.5, and the basic plant spacing is calculated to be 12cm by substituting the measured data.

[0016] In this embodiment, the method for calculating the dynamic offset includes: inputting local historical accumulated temperature data and fitting an accumulated temperature correction function, the expression of which is: ;in This is the accumulated temperature correction function. The effective accumulated temperature is greater than 12℃; the predicted tillering rate of cotton 20 days after sowing is calculated using the following expression: ;in The tillering rate of cotton. The average temperature 5-15 days after sowing. The average relative humidity is given 5-15 days after sowing. The dynamic offset is calculated based on the latitude of the planting site, the basic plant spacing, the accumulated temperature correction function, and the predicted tillering rate. The expression is as follows: ;in This is a dynamic offset. This is the offset adjustment factor. The tillering coefficient of cotton varieties. The latitude of the planting area, For reference latitude; in actual assessment, taking the compact cotton variety "Xinluzao X" planted in the Xinjiang cotton-growing area as an example, in the planting area at a latitude of 45°, the effective accumulated temperature / average temperature 5-15 days after sowing was calculated to be 22℃ based on meteorological forecast data (only the effective value of daily average temperature between 15-30℃ is counted, and days below 15℃ or above 30℃ are not included), and the average relative humidity 5-15 days after sowing was 72% (only the effective value of relative humidity within the range of 60%-80% is counted, and the boundary value is used when it is below 60% or above 80%). The reference latitude is used. 40°, offset adjustment coefficient The value is 0.57, and the dynamic offset is calculated to be 1cm (0.99cm is taken as 1cm).

[0017] In this embodiment, the method for determining the narrow row spacing and sowing depth based on the dynamic offset includes: taking the sum of the dynamic offset and the basic plant spacing as the narrow row spacing; taking the sum of the standard sowing depth and 0.1 times the dynamic offset as the sowing depth; in actual evaluation, the narrow row spacing is calculated to be 13cm based on the dynamic offset of 1cm and the basic plant spacing of 12cm, and the sowing depth is calculated to be 2.6cm based on 0.1 times the dynamic offset of 0.1cm and the standard sowing depth of 2.5cm.

[0018] In this embodiment, the method for determining the wide row spacing includes: extracting growth images of cotton of the same variety in the same region after the flowering and boll-forming period by using a drone, calculating the canopy coverage in the RGB image of the growth image, extracting the cotton row spacing within the preset range of canopy coverage, and calculating the average cotton row spacing as the wide row spacing; the preset range is 80%-85%; in actual evaluation, historical growth images of cotton of the same variety in the same region after the flowering and boll-forming period by using a drone, calculating the canopy coverage in the RGB image of the growth image, extracting the average cotton row spacing within the canopy coverage of 80%-85% as 63cm, taking 63cm as the wide row spacing, calculating the 6-row boundary width as 76cm*2+13=165cm according to the one-film-six-row wide-narrow-row dense planting staggered layout method, verifying that the 6-row boundary width of 165m is less than the maximum film width of 2m; taking the compact cotton variety "Xinluzao X" planted in Xinjiang cotton area as an example, the preparation before sowing is carried out as follows: (1) land preparation, loosening the soil to a depth of 30-35cm, and leveling the land (surface flatness ±2cm) (1) Within m), apply base fertilizer to the land (2000 kg / mu of organic fertilizer + 20 kg / mu of diammonium phosphate), and select appropriate pesticides according to the local pest and disease situation; (2) Seed treatment, select “Xinluzao X” cotton seeds with germination rate ≥85% and purity ≥95%, and coat them with insect-proof and disease-proof seed coating agent. Sun-dry the seeds for 4-6 hours 3-5 days before sowing; (3) Material preparation, select weather-resistant mulch film with a width of 2.0 m and a thickness of 0.01 mm, and select mulch film with a wall thickness of 0.2 mm and a drip spacing of 30 cm. The drip irrigation tape is embedded in the wall and is used with a precision seeder that can adjust the row spacing and plant spacing. In the planting area at a latitude of 45°, furrows are dug with a narrow row spacing of 13cm and a wide row spacing of 63cm. Sowing is carried out with a basic plant spacing of 12cm and a sowing depth of 2.6cm (the sowing quality requirements are: soil thickness of 1-1.5cm, sowing speed ≤4km / h, empty hole rate <2%, and misalignment accuracy >95%). Drip irrigation tape (with a dripper flow rate of 2-3L / h) is shallowly buried 2-3cm deep in the center of each narrow row.

[0019] In this embodiment, the method for dynamically controlling drip irrigation fertilization strategies includes: real-time monitoring of canopy photosynthetically active radiation (RALED), and adjusting the irrigation amount based on RLED, growth stage, and soil type, expressed as: ;in This represents the daily drip irrigation volume. Basic irrigation volume, The measured photosynthetically active radiation is located in the middle of the canopy. for The light saturation point during the reproductive period corresponds to photosynthetically active radiation. This represents the current leaf area index. for Optimal leaf area index during the growth period for Fertility adjustment coefficient, The soil texture coefficient is used. Topdressing strategies are determined based on the photosynthetically active radiation (PADR) of the canopy: nitrate nitrogen is applied when PADR is higher than the standard PADR range to promote photosynthetic nitrogen use efficiency; potassium fertilizer is applied when PADR is lower than the standard PADR range to enhance stem lodging resistance. In actual evaluation, taking the compact cotton variety "Xinluzao X" planted in the Xinjiang cotton-growing area as an example, a LI-190R PADR sensor was installed in the middle of the cotton canopy (approximately 50-60 cm above the ground, above the narrow rows) to monitor PADR in real time. Data was recorded every 20 minutes from 9:00 AM to 3:00 PM daily (the active period of cotton photosynthesis), and the average value of the effective data within 6 hours was taken as the measured PADR in the middle of the canopy for that day, in μmol / m². 2 •s, if it is a cloudy or rainy day, then abnormally low values ​​(<200μmol / m) will be removed. 2 •s), and interpolated with reference to data from nearby sunny days; when dynamically adjusting drip irrigation, a drone equipped with a multispectral camera (Parrot Sequoia+) was used to take aerial photos once a week, and the average leaf area index of the whole field was calculated using the NDVI-LAI inversion model (PROSAIL model). The light saturation point corresponds to photosynthetically active radiation, the optimal leaf area index, and the growth period adjustment coefficient, which are taken as 800 / 1200 / 1500 / 1000, 0.5 / 2.0 / 3.5 / 2.5, and 0.6 / 0.8 / 1.0 / 0.7 for seedling stage / bud stage / flowering stage / cotyl opening stage, respectively, corresponding to basic irrigation amounts of 8, 12, 18, and 10 mm / day. The soil texture coefficient is taken as 1.0 / 0.85 / 1.15 for loam / sandy loam / clay loam, respectively; the drip irrigation amount is updated daily. Taking the 75th day of the flowering and boll-forming stage as an example, the measured photosynthetically active radiation is 1350 μmol / m 2 Given the measured leaf area index of 3.2 and soil texture of loam (soil texture coefficient taken as 1), the drip irrigation amount on day 76 was calculated to be 14.82 mm. Based on a drip irrigation tape flow rate of 2 L / h·m, the irrigation time per meter of row length was calculated to be 123.5 min. When dynamically adjusting the topdressing strategy, the standard photosynthetically active radiation for each growth stage was set to 80%-100% of the light saturation threshold, i.e., 640-800 μmol / m². 2 ·s, 960-1200μmol / m 2 ·s, 1200-1500μmol / m 2 ·s, 800-1000μmol / m 2 •s; When photosynthetically active radiation is higher than the standard photosynthetically active radiation range, apply nitrate nitrogen as a top dressing, with the following application rate: ;in To determine the amount of nitrate nitrogen to be dynamically applied, The application rate of nitrate nitrogen as a base supplement is 5 / 15 / 25 / 10 kg / ha for the seedling stage / budding stage / boll-forming stage / cotyl opening stage, respectively. For wide line spacing, The standard row spacing is used; when the photosynthetically active radiation is below the standard photosynthetically active radiation range, potassium fertilizer should be applied as a top dressing, with the amount of fertilizer being: ;in This refers to the amount of potassium fertilizer to be applied dynamically. The amount of potassium fertilizer applied as base fertilizer corresponds to 3 / 10 / 20 / 8 kg / ha for the seedling stage / budding stage / boll-forming stage / cotyl opening stage, respectively. The controlled topdressing strategy is adjusted every 10 days, and the fertilizer is dissolved in the irrigation water of the day through the water and fertilizer integration system and applied through the drip irrigation system. At the same time, a drone equipped with a multispectral camera (Parrot Sequoia+) is used to take aerial photos once a week to calculate the wide row canopy coverage in the RGB images of the growth pictures. When the wide row canopy coverage reaches 85%, the inter-row crossing leaves are pruned, and 1 g / mu of mepiquat chloride is sprayed to prevent wound infection.

[0020] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for planting cotton in six rows with varying widths and spacing using a single film, characterized in that... Includes the following steps: S1. Measure the soil nutrient content in the planting area and calculate the comprehensive soil fertility score. Select the basic plant spacing based on the tillering coefficient of the cotton variety. S2. Input local historical accumulated temperature data, fit the accumulated temperature correction function, calculate the predicted cotton tillering rate 20 days after sowing, and calculate the dynamic offset based on the latitude of the planting site, the accumulated temperature correction function, and the predicted tillering rate. S3. Determine the narrow row spacing and sowing depth based on the dynamic offset. Extract growth images of cotton of the same variety in the same region after the boll-forming stage, and extract the average row spacing within the preset range of canopy coverage as the wide row spacing. S4. Plant cotton according to the basic plant spacing, narrow row spacing, wide row spacing, and sowing depth. Monitor the effective photosynthetic radiation of the canopy in real time, and dynamically adjust the drip irrigation and fertilization strategy based on the effective photosynthetic radiation of the canopy.

2. The cotton planting method with six rows of wide and narrow rows and staggered planting under one film as described in claim 1, characterized in that, The method for selecting the basic plant spacing includes: determining the soil nutrient content of the area to be planted and calculating the comprehensive soil fertility score; matching the plant spacing range based on the tillering coefficient of the cotton variety and domain knowledge; and calculating the basic plant spacing based on the maximum plant spacing and the comprehensive soil fertility score, expressed as: ;in Based on the basic plant spacing, This is the plant spacing adjustment coefficient. This is the maximum plant spacing. This is a comprehensive score for soil fertility.

3. The cotton planting method with six rows of wide and narrow rows and staggered planting under one film as described in claim 1, characterized in that, The method for calculating the dynamic offset includes: inputting local historical accumulated temperature data and fitting an accumulated temperature correction function, the expression of which is: ;in This is the accumulated temperature correction function. The effective accumulated temperature is greater than 12℃; the predicted tillering rate of cotton 20 days after sowing is calculated using the following expression: ;in The tillering rate of cotton. The average temperature 5-15 days after sowing. The average relative humidity is given 5-15 days after sowing. The dynamic offset is calculated based on the latitude of the planting site, the basic plant spacing, the accumulated temperature correction function, and the predicted tillering rate. The expression is as follows: ;in This is a dynamic offset. This is the offset adjustment factor. The tillering coefficient of cotton varieties. The latitude of the planting area, For reference latitude.

4. The cotton planting method with six rows of wide and narrow rows and staggered planting under one film as described in claim 1, characterized in that, The method for determining the narrow row spacing and sowing depth based on the dynamic offset includes: taking the sum of the dynamic offset and the basic plant spacing as the narrow row spacing; and taking the sum of the standard sowing depth and 0.1 times the dynamic offset as the sowing depth.

5. The cotton planting method with six rows of wide and narrow rows and staggered planting under one film as described in claim 1, characterized in that, The method for determining the wide row spacing includes: extracting growth images of cotton of the same variety in the same region after the flowering and boll-forming stage using a drone, calculating the canopy coverage in the RGB image of the growth image, extracting the cotton row spacing within a preset range of canopy coverage, and calculating the average cotton row spacing as the wide row spacing; the preset range is 80%-85%.

6. The cotton planting method with six rows of wide and narrow rows and staggered planting under one film as described in claim 1, characterized in that, The method for dynamically regulating drip irrigation fertilization strategies includes: real-time monitoring of canopy photosynthetically active radiation (RALED), and adjusting irrigation volume based on RLED, growth stage, and soil type, expressed as: ;in This represents the daily drip irrigation volume. Basic irrigation volume, The measured photosynthetically active radiation is located in the middle of the canopy. for The light saturation point during the reproductive period corresponds to photosynthetically active radiation. This represents the current leaf area index. for Optimal leaf area index during the growth period for Fertility adjustment coefficient, The soil texture coefficient is used as the basis for determining the topdressing strategy based on the photosynthetically active radiation of the canopy: when the photosynthetically active radiation is higher than the standard photosynthetically active radiation range, nitrate nitrogen is applied to promote photosynthetic nitrogen use efficiency; when the photosynthetically active radiation is lower than the standard photosynthetically active radiation range, potassium fertilizer is applied to enhance the lodging resistance of the stems.

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