China is a major producer and consumer of fruits， with output and area consistently ranking first in the world. However， China's orchards have long faced complex environments， with traditional manual operations facing high costs， labor shortages， and low efficiency. With the establishment of standardized and large-scale orchards， traditional models are no longer suitable for the development of modern orchards. The multi-functional operation technology platform integrates the functions of picking， ditching， fertilization， spray， transportation， etc.， effectively improves the efficiency of orchard operations， saves costs， and becomes the key tool for the efficient development of modern forestry and fruit industry. This article introduces the structural composition and working principle of a multifunctional homework platform， mainly introducing the two key parts of the lifting structure and chassis system， and provide an overview of the development trends of standardized orchard operation platforms at home and abroad， from simple mobile platforms to scalable platforms， followed by a series of improvements such as navigation and automatic leveling systems. By comparing the characteristics and advantages of different types of orchard operation platforms， clarify the shortcomings of domestic multi-functional operation platforms， and summarize and analyze the main research focus of multifunctional operation platforms at home and abroad， focusing on automatic leveling technology In terms of general chassis technology， navigation obstacle avoidance technology， lifting technology， chassis passability technology， power system coordination and management technology， and system quality improvement technology， this paper explores the bottlenecks faced by the development of multifunctional work platforms in China， such as insufficient intelligence and informatization， and relatively lagging policy support. Finally， suggestions are proposed to address the development gap between China's homework platforms and foreign homework platforms， such as promoting standardization and standardization of orchard planting， and developing towards intelligence and informatization， in order to provide development ideas for high-quality mechanized operations in China's orchards.

Intelligent plant protection machinery in large fields is an important means to improve pesticide utilization， enhance the quality of agricultural products， and ensure the sustainable development of agriculture. In order to understand the research status of intelligent plant protection technology and clarify the future development direction， this article focused on three main directions of intelligent operation of high-clearance plant protection machinery： prescription application in large-scale farmland， target spraying on a small scale in land parcels， and variable-speed spraying. From the aspects of perception， analysis， decision-making， and control， the article elaborates on the technical principles of prescription map construction， spatial coordinate transformation methods， and prescription recognition that integrate high-precision satellite positioning， the current level of key technologies for target spraying technology routes and weed recognition， and believed that high-precision spraying based on online prescriptions must be the focus of future research. The article carried out a comparative analysis of the advantages and disadvantages of four speed measurement modes for variable-speed spraying and believed that with the widespread application of satellite positioning in agricultural machinery， satellite-based speed measurement will become the main method of high-precision speed measurement due to its greater versatility， convenience， and accuracy. To explore the current development status of variable spraying control， the article summarized two control methods and implementation methods for pressure-controlled variable spraying. From a comprehensive perspective， pipeline cut-off flow control is the main way to achieve variable spraying， and three control algorithms of segmented control， pulse width modulation， and PID control of flow control were analyzed from the perspective of technical principles， implementation processes， and optimized applications. After the discussion， it is believed that PID control based on machine learning will be an important direction to improve traffic control performance. With the continuous development of artificial intelligence technology， plant protection robots that integrate intelligent perception， analysis and decision-making and autonomous operation capabilities will become the mainstream development direction of plant protection machinery in the future.

Pneumatic centralized seeding technology has the advantages of high seeding efficiency， wide adaptability and low seed damage. In the study， it was found that the type and structural parameters of the seed distributor had a great influence on the seeding uniformity of the pneumatic centralized seeding system. In this study， M-type， T-type and Y-type seed distributors were proposed respectively， and the overall structure and working principle of the pneumatic collection system were expounded. Taking wheat as the research object， the force and motion analysis of the seed particle group in the distributor under the action of airflow was carried out. Based on the CFD-DEM gas-solid coupling method， the simulation models of wheat seeds and distributors were established respectively. Taking the coefficient of variation of the uniformity of each row displacement as the index， the simulation test of the influence of different outlet types on the performance of the distributor was carried out， and the M-type seed distributor was determined as the optimal structure. On this basis， the influence of different outlet pipe inclination angles， top cover cone angles， inlet diameters， fillet radius and airflow velocity on the uniformity of the internal flow field of an M-type seed distributor was studied by single factor experiment， and the significant factors and their horizontal range were determined. The orthogonal test of three factors and three levels was carried out with the factors of outlet pipe inclination angle， top cover cone angle and fillet radius. The optimal structural parameters of the M-type seed distributor were determined by response surface analysis with the variation coefficient of uniformity of each row displacement as the index. The bench and field verification tests were carried out on the experimental farm of Northwest A & F University. The simulation and experimental results show that compared with the T-type and Y-type seed distributors， the M-type seed distributor significantly improves the seeding quality of wheat seeds， and the coefficient of variation of seeding uniformity is reduced by 7.41% and 3.72%， respectively. When the cone angle of the top cover is 117.03° and the angle of the outlet pipe is 59.50°， the corner radius is 69.46 mm， the uniformity of the seed distributor is the best， and the coefficient of variation of the uniformity of each row is 6.05%. The absolute errors between the simulation results of the M-type seed distributor and the bench and field test results were 1.00% and 1.55%， respectively. The research provides reference and technical support for the design of a pneumatic collecting and discharging system.

Agricultural robot is one of the hottest topics in the field of agricultural machineries. Domestic and foreign research on robot mobile platforms for greenhouse/farmland/orchard operations （weeding， fertilization， spraying， picking， etc.） has achieved preliminary results， but mobile robotic system for soil sampling is still seldom found in literatures. Undisturbed soil sampling is an important basis for analyzing soil mechanical properties. If the original state of the soil sample cannot be guaranteed， it will be difficult to obtain accurate research results through subsequent laboratory physical and mechanical testing and analysis. To address this issue， we developed a farmland soil collection robot mobile platform with compact structure， strong pass ability， good soil extraction quality， and high soil extraction efficiency， put forward the design scheme of the mechanical system and control system and carried out preliminary field trial research. The main contents of this research are as follows： First， the design of robotic mobile platform was conducted， by determining differential steering mode， fulfilling mechanical design， selecting hardware components， and building control software framework. The wheelbase and track width of the platform were 960 mm and 600 mm， respectively. The power of the in-wheel motor was 1 000 W. The movement of the platform could be controlled through both speed control knob and remote-control handle. Second， an on-board layer soil sampling equipment was developed， which worked in a hydraulic screw-in mode. The main structure parameters of the sampler were determined based on theoretical analysis， which were validated with a finite element analysis software-ANSYS. Third， field tests were also conducted to test the mobility and soil sampling performances of the robot system. The maximum obstacle crossing height and climbing slope of the robot were 80 mm and 35°， respectively. Based on the shear strength testing results of soil samples in depth 0 to 200 mm， we knew that the internal friction angle of the soil samples， which came from the proposed new system， had no significant differences compared to those coming from cutting ring sampling， with a P-value of 0.866 at the confidence level of 0.05. Similarly， for the soil samples in depth 0 to 100 mm and 100 to 200 mm， the variances of soil cohesion from our new system also had no significant differences compared to those from cutting ring sampling， with P-values of 0.145 and 0.717 at the confidence level of 0.05， respectively. The soil extraction efficiency comparison test results showed that the soil extraction device only took 3 to 5 minutes to complete one soil extraction.

In order to solve the problems of grain loss， breakage and impurity in sorghum harvest， the influence of maturity and mechanical harvest rate on the effect of combined harvest was studied. Taking Jinza No.22 sorghum as the research object， the plot experiment scheme was adopted， and three mechanical harvesting rates were set at the milk ripening stage， wax ripening stage and complete ripening stage， respectively， and the mechanical harvesting rates were set at 0.5 m/s， 1.0 m/s and 1.5 m/s， and the indexes such as crushing rate， impurity content， total loss rate and moisture content were measured， so as to obtain the influence rules of mature stage and mechanical harvesting rate on the harvesting effect. The results showed that the maturity stage and mechanical harvest rate had significant effects on the harvest indexes of sorghum， such as impurity content， crushing rate and total loss rate， and the most influential factors on the three harvest indexes were maturity stage. The best results can be achieved when the wax is ripe and the mechanical harvest rate is 1.0 m/s， when the grain moisture content is from 14.756% to 15.746%， the impurity content is 0.14%， the crushing rate is 0.29% and the total loss rate is 5.48%. This study obtained the influence law of mature period and mechanical harvest rate on sorghum harvest effect， which can provide theoretical basis for reasonable selection of mature period and popularization of harvesting technology of sorghum mechanization.

In recent years， the improvement of living standards in rural areas of developing countries and the continuous upgrading of rural industrial economy have led to increasingly serious rural sewage discharge. The rural sewage from production and domestic wastewater， agricultural tailwater， and aquaculture wastewater seriously damages the ecological environment， affecting residents' well-being and economic development. This paper points out the limitations of traditional ecological methods and biological treatment methods， such as long treatment cycles， significant environmental impact， and secondary pollution. Furthermore， it further discusses the advantages of plasma technology in treating rural sewage， including its wide application range， high treatment efficiency， and absence of secondary pollution， filling the gap in the application of plasma technology in agricultural wastewater treatment. Although some reaction mechanisms of plasma are still unclear， and the requirements for equipment are relatively high， which still need to be continuously improved. However， in the future， by combining with other technologies， the efficiency and application range of plasma technology can be further improved， enabling it to play a greater role in optimizing and improving the comprehensive treatment process of rural sewage in developing countries.

To effectively identify tea buds in complex environments and improve the precision of intelligent harvesting while minimizing damage to tea trees， this study addresses the issues of low detection accuracy and poor robustness exhibited by traditional target detection algorithms in tea gardens， and proposes YOLOv7-tea model for tea bud identification and detection based on an improved YOLOv7， so as to achieve rapid recognition and detection of tea buds.First， tea bud images were collected and annotated， and data augmentation was performed to construct a tea bud dataset. Next， the CBAM attention mechanism module was introduced into three feature extraction layers of the YOLOv7 backbone network to enhance the model's feature extraction capability； the SPD-Conv module was used to replace the SConv module in the neck network's downsampling module to reduce the loss of small object features； and the EIoU loss function was employed to optimize box regression， thereby improving the accuracy of the predicted boxes. Finally， a comparative experiment was conducted between other target detection models and the YOLOv7-tea model using the tea bud image dataset as a sample， and the recognition effect of tea buds shot at different distances and angles was tested.The experimental results show that the YOLOv7-tea network model outperforms the YOLOv7 model in terms of precision （P）， recall （R）， and mean average precision （mAP） by 2.87， 6.91， and 8.69 percentage points， respectively. Additionally， the model has a faster detection speed and exhibits higher confidence scores in the recognition and detection of tea buds in complex backgrounds.The YOLOv7-tea model constructed in this study demonstrates better recognition performance for small-sized tea leaf buds， reducing instances of missed detection and false alarms. It exhibits good robustness and real-time performance， offering valuable insights for estimating tea yield and implementing intelligent harvesting.

Fertilizer directly affects crop yield by regulating plant growth and development， and it is an important factor in promoting modern intensive agriculture for high yield and quality of crops. However， urea and urea containing compound fertilizers are prone to produce byproducts such as biuret. Currently， the high content of biuret in fertilizers causes crop toxicity in farmland， which cannot be ignored. Therefore， it is of practical significance to establish an efficient method for detecting biuret in fertilizers， ensuring the safety of fertilizer production and promoting the green and high-quality development of agriculture in China. This research is based on the urgent demand for high-quality fertilizers in the development of modern agriculture in China， and a sensitive electrochemical sensing interface based on carbon-based structural materials is constructed to achieve online and rapid evaluation of biuret in fertilizers and effectively overcomes the shortcomings of liquid chromatography and UV spectrophotometry， such as cumbersome sample pretreatment， high analysis cost， and large sample turbidity interference. During the electrochemical assay， a graphene-nanogold composite is firstly prepared as a sensing interface modification material， which combines the surface characteristics of carbon-based structure with the excellent conductivity of nanogold； Secondly， based on the inhibitory effect of biuret on electrochemical signal of copper ions， a linear regression equation is established for the response current of copper ions with the variation of biuret concentration. With the help of a smartphone obtaining electrochemical signal， rapid electrochemical analysis of biuret is achieved. The experimental results demonstrate that there is a good linear relationship between the response current generated by copper ions and the concentration of biuret in the range of 1-80 mmol/L， with a detection limit of 0.50 mmol/L （S/N=3）； The electrochemical sensing system is used for the analysis of biuret in fertilizer samples， and the relative errors between the detection results and those by high-performance liquid chromatography do not exceed 6.9%. Overall， this electrochemical method is applied to the online detection of biuret in fertilizers with high portability， reliability， and accuracy， aiming for technological innovation empowering crops with high yield and quality.

With the large-scale and intensive development of China's aquaculture industry， the discharge of livestock and poultry manure has increased significantly， causing serious pollution to the surrounding atmosphere， soil， water， etc.， affecting the survival and health of human beings， and hindering the sustainable development of aquaculture industry. China has issued a series of policies to protect environment and encourage the use of organic fertilizers， encourage the use of livestock and poultry waste to produce organic fertilizers， and replace chemical fertilizers with organic fertilizers. In response to the requirements of national environmental protection policies and solve the problem of livestock and poultry manure treatment， a horizontal fermentation drum for livestock and poultry manure was developed. The drum is helpful for livestock and poultry manure to complete the aerobic fermentation process and achieve the purpose of harmless treatment by mixing livestock and poultry manure with fermentation strains and other auxiliary materials， assistance in heating， aeration and stirring， monitoring the temperature of the material in real time， and the setting of electric heating， the start and stop of the drum and the running time. The structure， working principle and main technical parameters of the roller were described. The technological process of aerobic fermentation of cow manure was designed according to the principle and precautions of aerobic fermentation， and the fermentation performance test of manure horizontal fermentation roller was completed according to the process. The results showed that the organic matter content was 5.2% and the total nutrient （N+P₂O₅+K₂O） content was 5.1%， all of which exceeded the standard values of NY525—2012《Organic fertilizer》. The mortality rate of ascaris eggs and the number of coliform bacteria were both within the standard range of NY884—2012《Microbial organic fertilizers》. The horizontal fermentation roller has the advantages of simple structure， good manure treatment effects， short treatment period， simple operation and economical applicability， and it can meet the harmless treatment and resource utilization of livestock and poultry manure in small and medium-sized breeding enterprises.

In order to address the issues of large inclination angles and poor pass ability encountered by small-scale combine harvesters operating in hilly regions， a design and experimental study were conducted on an automatic lifting hydraulic system for the combine's chassis. This research developed the overall structure of the automatic lifting hydraulic system for the chassis， designed and selected key components such as hydraulic cylinders with built-in displacement sensors and directional proportional valves， and proposed methods for leveling and lifting the chassis by extending or retracting the hydraulic cylinders based on the transverse inclination angle. The study employed two leveling modes： automatic and manual， to level the chassis. The hydraulic system was simulated using AMEsim software， revealing stable pressure and flow within the hydraulic cylinders during direction reversing， along with smooth displacement velocity. A leveling control strategy centered on a PLC controller and PID control method was designed， which adjusted the length of the hydraulic cylinders to regulate the chassis's attitude and to conduct a static leveling experiment. Results indicated the proportional directional valve， when adjusted to a position between 20% and 45%， it can effectively regulate the velocity of both the extension and retraction movements of the hydraulic cylinders. The adjustment time increased with larger inclination angles， but the overall adjustment error remained below 0.5° within an inclination range of 7.7°， which can meet the requirements for transverse leveling of the combine harvester's chassis. This research introduced a hydraulic system and control method to realize leveling based on the transverse angle， providing a reference for the design of the chassis leveling hydraulic system for small-scale combine harvesters.

In China， the hilly and mountainous areas account for 34.62% of the total cultivated land and 34.20% of the total crop sown area， covering 54.2% of the population， while contributing only 30% to the national GDP. With the overall agricultural mechanization level below 50%， it is urgently needed to accelerate the development of agricultural mechanization in hilly and mountainous areas to build an agricultural powerhouse. Based on the agricultural tillage system zoning in China， this paper conducts a zoning of agricultural mechanization in hilly and mountainous areas， taking into account factors such as the distribution of hilly and mountainous areas. Based on the resource endowment conditions， economic and social conditions and industrial economic benefits， this paper summarizes the development status of agricultural mechanization， analyzes the special scenarios of agricultural machinery application from the aspects of cultivated land conditions， soil and agronomy， and analyzes the constraints and bottlenecks of agricultural mechanization development in combination with the factors of agricultural machinery research and development， manufacturing， promotion and application in hilly and mountainous areas of China. In the context of the application scenario in hilly and mountainous areas， ten key agricultural machinery general technology needs are proposed， such as compact and lightweight specialized engines， lightweight and anti-adhesion and anti-friction materials， and simplified machine structures. Ten applicable agricultural machinery equipment needs， such as efficient and low-cost tillage equipment in sticky soil， seeding equipment for grain， oil， sugar crops， and vegetables in mountainous areas for heavy and sticky soil in gentle slopes， and transplanting equipment for rape and vegetables in mountainous areas for heavy and sticky soil in gentle slopes， are also discussed. Drawing on the experience of agricultural mechanization in hilly and mountainous areas of Japan， Republic of Korea， etc.， this paper puts forward a systematic approach to promoting agricultural mechanization in hilly and mountainous areas， focusing on the integration of good machines， good seeds， good methods， good farmland， and good systems， and the four-in-one approach of research， production， promotion， and use. This approach aims to promote the high-quality development of agricultural mechanization in hilly and mountainous areas.

Laser， as an emerging artificial light source， is one of the greatest inventions of the 20th century， featuring high power density， excellent directionality， and superb monochromaticity. It has been widely applied in the agricultural sector. This article provides an in-depth analysis of the research progress and development trends of laser technology in agriculture. In plant production， it discusses applications in plant mutation breeding， promoting plant growth and development， enhancing yield and quality， plant protection， plant detection， and phenotyping. In animal management， the focus is on the use of laser technology in animal genetic breeding， growth， medical care， and product testing. For fungal research， it summarizes the use of laser technology in fungal breeding， growth， detection， and identification. The article also addresses the challenges and difficulties faced when integrating laser technology with agricultural production， proposing directions for future development， such as improving precision in plant production， optimizing animal management， and advancing scientific fungal production. Although laser technology has already achieved significant results in agriculture， future research should explore more innovative applications and integrate with artificial intelligence and big data technologies to further advance the deep integration of laser technology with the agricultural industry， leading to more efficient and intelligent agricultural production management and offering new opportunities and breakthroughs for modern agriculture.

Panax Notoginseng is one of the most extensively cultivated and utilized bulk medicinal materials in China， and Yunnan Province is the main producing area for Panax Notoginseng in the country. Due to the influence of terrain and agronomic requirements， traditional agricultural machinery faces difficulties in entering the planting areas for operation， resulting in the current manual operation of Panax Notoginseng transplantation. Therefore， the development of a Panax Notoginseng transplanting machine is crucial for promoting the industrialization of Panax Notoginseng. As the crucial load-bearing structure of the transplanting machine， the frame significantly affects the overall performance of the vehicle. This paper focuses on the structural analysis of the transplanting machine frame， aiming to improve the performance of the frame and the entire vehicle， and provide theoretical basis for frame structural design. A three-dimensional model of the frame is established using SolidWorks software and imported into ANSYS software for static finite element analysis. After determining the relative error range between the stress values obtained from static electrical tests and experimental stress values， the dynamic loading performance of the frame under different working conditions and the modal vibration deformation analysis of the first eight modes are conducted. The analysis results indicate that the frame exhibits good strength performance， but significant deformation occurs at the seat position， indicating insufficient stiffness of the structure. Topology optimization is employed to optimize the frame design， aiming to reduce frame deformation while ensuring reasonable stress distribution. By altering the arrangement of diagonal brace brackets， the goal of reducing deformation is achieved. According to the optimization design results， the total mass of the frame increases by 8.739%， while the deformation is reduced by 88.268%， and the maximum stress is decreased by 11.693%. The improved frame exhibits reduced maximum stress and significantly improved deformation， demonstrating the applicability of finite element method and topology optimization technology in guiding the structural design of transplanting machine frames.

Traditional angle sensors have problems such as insufficient accuracy and complex installation and debugging when measuring the deflection angle of tractor guide wheels， which hinder the high precision and stability requirements of tractor automatic navigation operations. Therefore， this paper aims to construct and validate a novel system based on the principles of Global Navigation Satellite System （GNSS） and Inertial Navigation System （INS）， which is capable of real-time calculation of dynamic angles of the tractor's steering wheel. First， a in-depth analysis of GNSS/INS fusion principles was conducted， and corresponding GNSS/INS data measurement bench tests were designed to obtain measurement values from angle sensors. Subsequently， three filtering algorithms， namely Kalman Filter （KF）， Extended Kalman Filter （EKF）， and Unscented Kalman Filter （UKF）， were employed to filter the angle measurement values， evaluating metrics such as overshoot， response time， and stability， and the results showed that UKF performed best in this system. Second， steering and straight-line performance tests were conducted under different conditions （asphalt road and farmland） for tractor automatic navigation. In the steering performance tests， fixed measurements at different angles of 1°， 5°， and 15° were conducted， and the results showed that the response time of the two environments was the smallest at 1°， but both produced the largest overshoot. At the same time， an increase in angle demonstrated a significant reduction in steady-state error. In the straight-line automatic navigation performance tests， the maximum lateral deviations for asphalt road and farmland were 17.51 mm and 18.52 mm， respectively， with system errors of 10.45 mm （2σ） and 21.07 mm （2σ）. A comparison between the two conditions indicated superior performance metrics on asphalt road， yet both conditions met the requirements of precision， response time， and stability for automatic navigation systems， thus suitable for tractor automatic navigation operations.

In response to the problems of poor speed stability and degraded spraying quality of 4WID high-clearance self-propelled electric sprayers caused by changes in external road gradients and lowered payloads resulted from internal liquid spraying under complex operating conditions， a fixed-speed cruise control algorithm with a layered control approach is proposed based on an analysis of the structure and longitudinal dynamic characteristics of 4WID high-clearance self-propelled electric sprayers. The control algorithm model receives the user-specified desired speed and inputs acceleration control signals to the longitudinal dynamic system model through algorithmic calculation to realize the tracking of the sprayer to the desired speed. The structure of the longitudinal dynamic system mainly includes five parts： the inverse longitudinal kinematic model， the acceleration-braking switching model， the torque allocation model， the motor model， and the longitudinal kinematic model. The inverse longitudinal kinematic and longitudinal kinematic models of the sprayer can be obtained by analyzing the force on the body of the sprayer under the condition of driving on a slope. Meanwhile， in order to establish a reasonable four-wheel torque allocation strategy， the analysis is conducted under the condition that the sprayer has both pitching and tilting motions of the body， and the slip rate of each driving wheel is used as the basis for allocation， ensuring the optimal torque moment of each wheel under different operating conditions and ensuring the balanced power of the sprayer. The speed cruise control adopts a layered control approach， which realizes the effective tracking of the speed of the spraying machine through the establishment of the upper PID control and the lower fuzzy PID control. By defining fuzzy control rules， the PID parameters of the lower layer controller are automatically adjusted to ensure the good adaptability of the speed cruise control system to various complex operating conditions. A control model is established using Matlab/Simulink， and the control system is simulated and analyzed. The experimental results show that the designed speed cruise control system can effectively control the speed of the sprayer under typical operating conditions. Specifically， the performance of the system is excellent under conditions of external disturbance and self-weight variation， with overshoot less than 2%， response time less than 0.2 s， and steady-state error approaching 0， verifying the accuracy of the control algorithm used.

Rice seedlings need sufficient light for normal growth. The increasing temperature demand of early spring seedling has promoted the development of greenhouses， greenhouses and factory facilities. However， due to the reflection and absorption of sunlight by glass and plastic， the lack of light in facility seedlings is prominent. Supplementary lighting can better solve the problem of lack of light in facility seedling， LED as the representative of the supplementary light source has been promoted and applied in facility seedling， but it still has high energy consumption problem. Laser is the only artificial light source with parallel light characteristics of sunlight， with good correlation， good monochromism， good directivity， high brightness， large energy， photoelectric conversion efficiency， energy saving and so on. Studies have shown that the special light quality of laser can effectively improve the photosynthesis efficiency of seedlings. The traditional laser light source represented by He-Ne laser is large in volume， high in cost， and difficult to be popularized. Using semiconductor laser combined with uniform light technology to develop a new laser light source， small size， low cost， can achieve a large area of uniform laser irradiation of rice seedlings， the single lamp irradiation area can reach 60-70 square meters. At the same time， the new laser light source retains the traditional laser correlation， monochromism and directivity， and also has the characteristics of high efficiency and energy saving， and the energy consumption can be only 1/30 of the traditional LED light source. The results showed that reasonable irradiation of new laser light source in the process of rice seedling cultivation can improve the quality of seedlings， fast greening after transplanting， more tillers， early heading， and finally achieve stable and increased rice yield. Since 2021， the test results in many places across the country have shown that the use of a new laser light source to irradiate rice seedlings for about 20 days before transplanting can achieve a yield increase of more than 10%. This result not only provided important technical support and guarantee for improving the quality and yield of rice in China， but also provided a new method and means for other plants to fill light at various stages.

Nitrogen is one of the important elements for the growth and development of rice， and accurate estimation of nitrogen concentration is crucial for guiding precise fertilization and assisting in the selection of nitrogen efficient varieties in rice. Traditional field sampling methods make it difficult to obtain real-time nitrogen concentration in rice. With the rapid development of information technology， establishing the relationship between unmanned aerial vehicle hyperspectral data and nitrogen concentration through machine learning methods is currently one of the main technical routes for crop nitrogen nutrition diagnosis. This study constructs an inversion model by using the feature bands of unmanned aerial vehicle canopy hyperspectral data selected by the continuous projection algorithm as input and the measured nitrogen concentration data as output. Extreme learning machine （ELM） has the advantages of fast speed and strong generalization ability compared to similar machine learning methods. However， due to its randomly generated connection weights and neuron thresholds， its training stability is insufficient and it is prone to falling into local optima. The beluga whale optimization （BWO） is a competitive algorithm inspired the behavior of beluga whales to solve single modal and multimodal optimization problems. In this study， the BWO-ELM rice nitrogen concentration unmanned aerial vehicle hyperspectral inversion model was constructed to achieve rapid estimation of rice nitrogen concentration by optimizing the connection weight between the input layer and the hidden layer of the ELM， as well as the initial weight of the hidden layer through the BWO. The research results show that the continuous projection algorithm filters out 10 feature bands， which are 673， 703， 727， 823， 850， 877， 895， 952， 961， and 985 nm， respectively. The training set R² and RMSE of the nitrogen concentration inversion model constructed based on BWO-ELM are 0.742 5 and 0.382 6%， respectively， while the testing set R² and RMSE are 0.702 8 and 0.487 7%， respectively. The predictive ability is superior to that of the nitrogen concentration inversion model constructed based on ELM. In summary， the rice nitrogen concentration unmanned aerial vehicle hyperspectral inversion model based on BWO-ELM can quickly and accurately obtain rice nitrogen concentration， providing a new method for rice nutrition monitoring.

As agricultural production continues to increase its requirements for field management， traditional agricultural machinery and equipment have gradually become difficult to meet the production needs of modern smart agriculture. In this context， soil moisture monitoring technology， as a key means of obtaining soil moisture information in modern agricultural management， is playing an important role in promoting the development of agricultural machinery towards intelligence and automation. Therefore， this study thoroughly reviews and analyzes the current research status of soil moisture monitoring technology at home and abroad， focusing on the research progress of three aspects of soil moisture monitoring methods and principles， model construction algorithms， and signal processing methods. Through comparative analysis， the differences and similarities in monitoring methods， principles， model construction algorithms， and signal processing methods at home and abroad， as well as the problems and challenges in practical applications， are summarized. The future development trends of soil moisture monitoring technology in these three aspects are proposed： in terms of soil moisture monitoring methods， a multi-source soil moisture monitoring information platform is constructed to achieve more comprehensive data collection and analysis； In terms of model construction algorithms， machine learning and deep learning algorithms are adopted to customize model algorithm modules for different soil environments and working scenarios， improving the accuracy and applicability of monitoring equipment； In terms of signal processing， the application of multi-source signal fusion technology is strengthened to reduce the impact of the working environment on monitoring equipment.

The realization of automatic identification and positioning of tea buds is the basis for the development of high-quality tea intelligent picking equipment. Aiming at the problems of tiny tea buds and the picking environment which is greatly affected by light， this research proposes a tea bud recognition method based on a deep learning network model to carry out the light source design of the recognition system， which can provide technical support for the realization of all-weather and high-efficiency intelligent tea bud picking equipment. First， an aluminum alloy frame was constructed to provide a closed and shaded dark environment； then， three combinations of heights and three combinations of light intensities were created by adjusting the height of the crossbar and the brightness of the light source； finally， the image datasets of tea buds in different combinations were collected， and recognition tests were carried out on one bud and one leaf and one bud and two leaves by using the improved YOLOv5 model. The experimental results show that the overall accuracy of YOLOv5s is 77.13%， and the overall average precision mean is 86.14%， the overall accuracy of the improved recognition model YOLOv5s-SPD is 80.30%， and the overall average precision mean is 87.3%， and the average detection time of a single image is 5.7 ms， which meets the requirement of real-time detection， and is better than the original YOLOv5s with an overall accuracy improvement of 3.17% and an overall average precision mean of 1.16%， which effectively improves the recognition performance of tea buds. Under the condition of height 90 cm and luminance L7（0.164~0.328 \mathrm{\mu }\mathrm{m}\mathrm{o}\mathrm{l}/{\mathrm{m}}^{\mathrm{2}}）， the detection accuracy， recall and AP average of one bud and two leaves were 86.70%， 92.45% and 95.00%， respectively. The method proposed in this paper can effectively and quickly detect tea buds， and the light source design scheme supports the development of all-weather high-quality tea intelligent picking equipment.

With the development of agricultural science and technology， the utilization of crop straw has become more diversified， and its demand has also increased. This paper aims to solve the disadvantages of small round baler in hills and mountainous areas， such as easy scattering of bales， unadjustable number of net layers and low degree of automation. The net-wrapping device was modularized， including the design of the net feeding mechanism， the net cutting mechanism， the detection mechanism and the control circuit， and the mechanical analysis of the net feeding mechanism was carried out. The operation parameters of the device are detected by the detection device， and send to corresponding execution instructions to the feeding mechanism and cutting mechanism after processing by the controller， thus realizing the automatic operation of feeding， winding and cutting， and realizing the adjustable number of winding layers. When the net is wrapped， the friction torque limit component exerts tension on the net， so that the net is more tightly wound， the mechanical analysis found that the net tension depends on the compression spring elasticity， and the corresponding adjustment method is provided. The performance test results show that the device has stable performance and reliable operation. It can automatically wrap the hay bale of \Phi 500 mm×700 mm. The wire net covers the side of the bale without leakage and entangling. When the number of layers is 3， the success rate is 95% and the anti-fall rate is 83.3%. When the number of layers is 4， the success rate of wrapping is 100%， and the anti-fall rate is 90%. When the number of net layers is 5， the success rate of net-wrapping and the anti-fall rate of bale are 100%. This paper designed a small automatic net-wrapping mechanism for small round baler in hills and mountains areas， the test verified that the performance of the machine is stable and reliable， meet the design requirements. When the number of layers is 3， the cost performance of flat operation is the highest， and when the operation is hilly and mountainonous areas， it needs to be adjusted to 4-5 layers to the slope of the operation.