Plug Seedlings Research Articles

Design of picking seedling device for plug seedling transplanter

Plug seedlings are the main way of modern seedling cultivation in China. Aiming at the problems of low efficiency, high labor intensity and poor work quality for manual transplanting or semi-automatic transplanting of plug seedlings, a stable and efficient seedling picking device is designed for the automatic transplanting machine. It is based on the gear-cam-link composite mechanism to realize the seedling trajectory in accordance with the agronomic requirements. The mathematical model of the seedling picking device is established, and the theoretical profile equation of the cam groove and the actual picking trajectory equation are deduced. The 3D model and the virtual prototype model of the picking seedling device are constructed, and the simulation trajectory is obtained, using SolidWorks and ADAMS software. The simulation results show that the simulation working trajectory has good consistency with the theoretical trajectory.

The effect of transplant age on vegetable growth characteristic in a cylindrical paper pot system

This study aimed to estimate the seedling performance of cylindrical paper pot (CPP) seedlings and to determine the optimal transplanting age of CPP seedlings based on seedling vigor. The studied vegetables were cucumber, tomato, paprika, and two varieties of cabbage, and the younger seedlings were obtained by shortening their raising period by 10 and 20 days with CPP. At the same transplanting age, the size of CPP seedlings was smaller pre-transplant but increased to a similar level to the plug seedlings soon after transplanting. The growth curves of leaf area and dry weight of younger CPP seedlings exhibited a steeper rise trend. The seedling vigor indicators, relative growth rate (RGR), net assimilation rate (NAR), were significantly increased in younger CPP seedlings of all vegetables, which were 10 or 20 days younger than plug seedlings. The compactness (CP) and seedling health index (SHI) of cucumber, and the leaf area ratio (LAR) and specific leaf area (SLA) of cabbage were significantly increased when shortened by 10 and 20 days, while the CP and SHI of paprika were significantly decreased when shortened by 20 days. Our results suggest that CPP may prevent the seedlings from overstretching and can provide a wild range of transplanting age choices to produce vigorous seedlings. Further, the seedling vigor indicators were successfully used to determine the transplanting age of CPP seedlings. The optimal transplanting age of CPP seedlings of tomato, paprika, and cabbage was 10 days younger than plug seedlings, whereas cucumber transplanting age could be decreased by either 10 or 20 days.

Development of a multi-adaptive feeding device for automated plug seedling transplanter

In order to improve the adaptability of the seedling feeding devices to different plug trays for various seedlings, a multi-adaptive plug seedling feeding device for automatic field transplantation was developed. Its efficiency and adaptability have been improved using a seedling delivery device equipped with a row of end-effectors, which were provided with continuous plug seedlings by a compact seedling tray conveyor carrying out a reciprocating action. Each operation for the seedling feeding device could work automatically through a control system. Three categories of plug seedlings, cucumber, pepper and tomato seedlings, were tested. The results of the performance test for the prototype demonstrated that the best performance emerged in the cucumber seedlings in 50-cell trays with the highest success rate of 88% at the feeding frequency of 6 groups/min. The lowest success rate was 73.33% for the tomato seedlings in 105-cell trays at the feeding frequency of 12 groups/min. It can be concluded that the automated feeding device developed in this study could be used for various plug seedlings as a result of its strong adaptability. Keywords: plug seedling, automated feeding device, vegetable transplanting, control system DOI: 10.25165/j.ijabe.20211402.6003 Citation: Shao Y Y, Han X, Xuan G T, Liu Y, Gao C, Wang G P, et al. Development of a multi-adaptive feeding device for automated plug seedling transplanter. Int J Agric & Biol Eng, 2021; 14(2): 91–96.

Design and experiment of intelligent sorting and transplanting system for healthy vegetable seedlings

Healthy vegetable seedlings are surviving seedlings with good biological characteristics. Selective planting of healthy seedlings in the mechanized transplanting process can effectively avoid the reduction in yield caused by missed planting. Aiming at the current transplanting machinery that cannot achieve the selective planting of healthy seedlings, a healthy seedling intelligent sorting and transplanting system was proposed. The system consisted of a seedling delivery mechanism, sorting mechanism, photoelectric sensor, image sensor, PLC control system, and computer control system. It can realize automatic transmission of seedling trays, automatically identify the information of healthy seedlings in the trays and selectively transplant them. Also it can reduce the missed planting rate caused by the poor quality of plug seedlings after planting and the lack of seedlings in the hole. A sorting test of plug seedlings was carried out for the age-appropriate pepper plug seedlings cultivated in the factory. The results showed that the system had an average recognition accuracy rate of 89.14% and an average sorting success rate of 93.20% in the process of sorting suitable age pepper plug seedlings. The whole system can identify, sort and transplant the plug seedlings of appropriate age according to healthy information, and effectively avoid missing planting. This research can provide technical support for the intelligent upgrade of transplanting equipment. Keywords: intelligent agriculture, sorting and transplanting system, healthy vegetable seedling, design, experiment, image, sensor DOI: 10.25165/j.ijabe.20211404.6169 Citation: Li M Y, Jin X, Ji J T, Li P G, Du X W. Design and experiment of intelligent sorting and transplanting system for healthy vegetable seedlings. Int J Agric & Biol Eng, 2021; 14(4): 208–216.

Development of embedded automatic transplanting system in seedling transplanters for precision agriculture

Hand transplanting of vegetable seedlings is always been a time consuming and labourious activity which often leads to muscular fatigue. Use of hitech instrumentation increased to achieve precision and automation in agricultural operations. At present the transplanting is done manually which accounts for large amount of hand labour and time. To ensure precision and timeliness in operation, an automatic transplanting based on embedded system for use in seedling transplanters was developed. The developed system consists of feed roller, pro-tray belt, a pair of L-shaped rotating fingers, embedded system, DC and stepper motor. The plug seedlings were released into the furrow with use of developed embedded system by actuating DC as well as stepper motor. The performances of the developed system was tested rigorously at four different operating speeds (1.0, 1.5, 2.0 and 2.5 km/h) and three angles of pro-tray feed roller (00, 300, 450) for attaining optimum plant to plant spacing in soil bin. The result indicated that percent transplanting and plant to plant spacing was found optimum at 2.0 km/h forward speed and 300 angle of pro-tray feed roller. The average plant spacing, transplanting efficiency, furrow closer, angle of inclination and miss planting were 600 mm, 91.7%, 90.3%, 18.30 and 2.1%, respectively. The developed system ensures the precision by sigulating the placement of seedlings at optimum spacing for sustainable agriculture production. It also enabled the optimum transplanting rate, the ability to transplant at higher speeds and maintaining proper plant to plant spacing.

Design and testing of the mechanical picking function of a high-speed seedling auto-transplanter

To improve the low transplanting efficiencies and simplify the complex structures of current automatic transplanters, a mechanical high-speed transplanter for picking plug seedlings that is suitable for planting on plastic films was designed. The main components were an automatic seedling picking system and a basket-type planting system, which were used for the following processes: automatic picking, planting, soil covering, and suppression of plug seedlings. The performance test was performed on the automatic transplanter with 60-day-old pepper seedlings. The transplanting efficiency was tested at speeds of 40, 60, 90, and 120 plants·min−1. The results showed that the coefficient of variation (CV) of the plant spacing and the missed transplanting rate increased with the planting frequency, whereas the qualified rate of planting perpendicularity and the qualified rate of planting decreased with the increase in the planting frequency. All planting indices met the JB/T 102912013 standards. The results of this study showed that the auto-transplanter could perform high-speed transplanting on the basis of completing the following functions: automatic picking, planting, soil covering, and suppression of plug seedlings.

Growth of Tomato and Pepper Grafted Plug Seedlings under Different Shading Condition During Acclimatization after Graft-taking

Growth of Tomato and Pepper Grafted Plug Seedlings under Different Shading Condition During Acclimatization after Graft-taking

Design and development of an automatic vegetable transplanter using a novel rotating finger device with push-type mechanism for plug seedlings

ABSTRACT Manual vegetable transplanting is a time-consuming, labor-intensive, operation. The objective of the study was to design, develop, and evaluate an automatic vegetable transplanter (AVT) for plug seedlings of chili (Capsicum annuum L.). Metering mechanisms in an AVT are affected by the transmission system and changes in desired plant spacing. To overcome problems, a novel rotating finger device with a push-type mechanism was developed for automatic transplanting of vegetable plug seedlings. The AVT consists of a pair of L-shaped rotating fingers, feed roller unit, metering mechanism, and delivery unit. Clearance between the feed roller and fingers is adjustable. The average values of performance parameters: plant spacing (Ps), planting depth (Pd), mis-planting (Mp), multiple planting (Mt), seedling mortality (Sm), transplanting efficiency (Et), and field transplanting efficiency (Ef) were 599.8 mm, 46.4 mm, 4.9%, 1.1%, 0.9%, 92.6%, and 76.12%, respectively. Effective field capacity (Fc) with the transplanter was 0.093 ha∙h−1 and 0.027 ha∙h−1 with the manual method. The two-row AVT can be used with a small tractor and may make up for labor shortage during peak season.

Growth Suppression of Tomato Plug Seedlings as Affected by Material Type for Brushing Stimulation

Growth Suppression of Tomato Plug Seedlings as Affected by Material Type for Brushing Stimulation

Synthetic Seed Technology Development and Production Studies for Storage, Transport, and Industrialization of Bracken Spores.

Bracken fern (Pteridium aquilinum var. latiusculum (Desv.) Underw. ex A. Heller) has long been grown industrially in South Korea. Conventional propagation methods, including planting rhizomes and in vitro seedling culture, are labor intensive and expensive, and thus not commercially suitable. We aimed to develop a system to produce synthetic seeds using fern spores (SFS). Synthetic seeds were prepared by mixing bracken spores and alginate matrix. Spore germination and gametophyte and sporophyte growth and development from SFS proceeded normally. Spore density affected gametophyte and sporophyte numbers. SFS prepared using cold (4 °C) long-term storage spores (even 7-year-old spores) could effectively form sporophytes. The highest germination was observed at 25 °C. Soaking-treated SFS successfully formed sporophytes, even after 30 days of storage at 4 °C; indeed, sporophytes formed even after five days of storage at 25 °C during transport conditions. SFS were sown in plug trays for commercial use. Young sporophytes grown from plug seedlings were greenhouse cultivated, and transplanting within eight weeks was effective for root growth and growing-point formation. Developing synthetic seeds is a feasible solution for facilitating efficient transport and the handling of small-sized fern spores; furthermore, this SFS technology provides the basis for fern seedling culture and fern spore industrialization.

Effect of Compound Biochar Substrate on the Root Growth of Cucumber Plug Seedlings

Since plug seedling plays a key role in automatic transplanting, this work aimed to explore the effect biochar has on the root growth of plug seedlings. The physicochemical properties tests showed that the addition of biochar in the peats could increase the porosity, pH, and EC values of the substrate, and the substrates treated with 0%, 10%, 20%, and 30% biochar could meet the requirements of seedling raising. The water retention of the substrate was superior with the increase of biochar proportion, and the nitrogen release significantly decreased with the increase of the biochar proportion. Our results demonstrated that the substrate with 10% biochar-treated apparently promoted the growth of seedlings and root systems, even the length of the root-tip cells. However, the substrates with 40% and 50% biochar-treated obviously inhibited the growth of seedlings and root systems. It was noticed that the strength of substrate with appropriate biochar proportion was enhanced, as well. Under the interaction of strong root system and solid substrate, the compressive strength of the substrate with 20% and 10% biochar-treated was much better than others, especially that of 40% and 50% biochar-treated, which efficiently satisfied the requirements of automatic seedling picking. The biochar may have a good application prospect in seedling raising.

Trajectory planning and motion control of full-row seedling pick-up arm

Frequent start-stops of automatic seedling transplanters would lengthen the seedling picking time due to alternating movement of the motor, and cause positioning errors and frequent motor vibrations when starting the machine. To solve these problems and ensure the pick-up continuity of automatic transplanters, in this study the smooth circular arc interpolation algorithm and the least square method for multinomial curve fitting were used to conduct the trajectory planning of automatic transplanter based on the movement of the pick-up arm of the transplanter. Velocity and time curves were fitted in segments to acquire motion control parameters and further tracking control was conducted. The mathematical model of the control system was established using Simulink, and simulation analysis and system debugging test were performed. Experiments show that the trajectory curves obtained by MATLAB’s data processing can realize the continual and smooth motion trajectory of the pick-up arm; stepper motor velocity control can effectively track the planning curve and improve the seedling pick-up efficiency. The pick-up and pushing time of each motion of the planned plug seedling transplanter reduced by 1.0678 s and the start-stop times reduced from 6 to 1, which solved the frequent motor vibrations when starting the machine and improved the stability of the system. In addition, overstep and out-of-step of the motor at the start-stop moment were avoided and displacement error was reduced. Keywords: trajectory planning, motion control, motion trajectory simulation, transplanter, stepper positioning DOI: 10.25165/j.ijabe.20201303.5264 Citation: Ren L, Wang N, Cao W B, Li J Q, Ye X C. Trajectory planning and motion control of full-row seedling pick-up arm. Int J Agric & Biol Eng, 2020; 13(3): 41–51.

Dynamic changes in bacterial communities in the recirculating nutrient solution of cucumber plug seedlings cultivated in an ebb-and-flow subirrigation system.

Ebb-and-flow subirrigation systems are highly efficient, water-saving and environmentally friendly. However, one concern with these recirculating systems is the possible transmission of plant pathogens. Here, through 16S rRNA-targeted Illumina sequencing, the bacterial dynamics in a recirculating nutrient solution were characterized for cucumber plug seedlings cultivated in an ebb-and-flow system in summer and winter. Both the bacterial number and diversity in the nutrient solution increased immediately after the first irrigation cycle; then, these values were gradually stable with recirculating irrigation. In summer and winter, different bacterial compositions and changing patterns were observed. In summer, the predominant genera in the nutrient solution included Comamonas, Pseudomonas, Acinetobacter, Reyranella, Sphingobium, Bradyrhizobium, Sphingomonas, and Acidovorax. Of those genera, during recirculating irrigation, the relative abundance of Bradyrhizobium gradually decreased, whereas those of Pseudomonas, Reyranella, Sphingobium, Sphingomonas, and Acidovorax gradually increased. In winter, the bacterial communities were mainly composed of Nevskia, Bosea, Sphingobium, Acidovorax, Pseudomonas, and Hydrocarboniphaga. Of those genera, the relative abundance of Bosea, Sphingobium, and Acidovorax showed an increasing trend, whereas those of Nevskia and Hydrocarboniphaga decreased overall. Furthermore, in both summer and winter, no plant pathogenic bacteria on cucumber could be detected; however, some potentially beneficial bacteria, including Comamonas testosteroni, Acinetobacter baumannii, Pseudomonas aeruginosa, P. koreensis and Sphingobium yanoikuyae, colonized the nutrient solution and exhibited increased relative abundances during irrigation. The colonization of these bacteria might facilitate the plant growth promotion. Inoculation of the microbes from the effluent nutrient solution also promoted the growth of cucumber seedlings, but did not lead to any disease. The present data elucidate the bacterial dynamics in a cucumber cultivation ebb-and-flow system and provide useful information for biological control during cucumber seedling production.

Effect of diniconazole on the growth and taking roots after transplanting of Sesamum indicum ‘Baekseol’ plug seedlings

Sesamum indicum ‘Baekseol’ plug seedlings were treated with the fungicide diniconazole as a growth retardant in comparison to paclobutrazole. Seeds were sown in 128-cell plug trays. Paclobutrazole (0, 15, 30, and 60 mg L−1) and diniconazole (100, 200, 300, and 400 mg L−1) were foliage sprayed when first leaves were developed. Stem growth was similar between paclobutrazole and the control, but strongly retarded by increasing concentrations of diniconazole. Leaf numbers did not differ in all treatments. As the diniconazole concentration increased, leaves became thicker, while leaf width and length decreased. In diniconazole treatment, shoot fresh weight decreased, but root fresh weight increased. Therefore, the T/R ratio was lowered by diniconazole treatment. After transplanting, the taking roots of paclobutrazol-treated plants were below average (< 50%), whereas, with diniconazole treatments, it was 100%, regardless of treatment concentrations. From the above results, 100 mg L−1 of diniconazole is the most appropriate for growth retardation of S. indicum ‘Baekseol’ plug seedlings.

Effect of Supplementary Lighting Duration on Growth and Activity of Antioxidant Enzymes in Grafted Watermelon Seedlings

Insufficient exposure to light in the winter may result in a longer production periods and lower quality of seedlings in greenhouses for plug growers. Supplementary artificial lighting to plug seedlings may be one solution to this problem. The objective of this study was to assess the effects of the duration of the supplementary light on the growth and development of two watermelon cultivars, ‘Speed’ and ‘Sambok Honey’ grafted onto ‘RS-Dongjanggun’ bottle gourd rootstocks (Lagenaria siceraria Stanld). Seedlings were grown for 10 days in a glasshouse with an average daily natural light intensity of 340 μmol·m−2·s−1 photosynthetic photon flux density (PPFD) and daily supplementary lighting of 8, 12 or 16 h from mixed LEDs (W1R2B1, chip ratio of white:red:blue = 1:2:1) at a light intensity of 100 μmol·m−2·s−1 PPFD, a group without supplementary light was set as the control (CK). The culture environment in a glasshouse had 25/15 °C day/night temperatures, an 85 ± 5% relative humidity, and a natural photoperiod of 8 h. The results showed that all the growth and development parameters of seedlings grown with supplementary light were significantly greater than those without supplementary light (CK). The 12 and 16 h supplementary light resulted in greater growth and development parameters than the 8 h supplementary light did. The same trend was also found with the indexes that reflect the quality of the seedlings, such as the dry weight ratio of the shoot and root, total biomass, dry weight to height ratio of scions, and specific leaf weight. The 12 h and 16 h light supplements resulted in greater Dickson’s quality indexes compared to the 8 h supplementary light, and the 12 h supplementary light showed the greatest use efficiency of the supplementary light. 16 h of daily supplementary light significantly increased the H2O2 content and the antioxidant enzyme activities in seedlings compared to the other treatments. This indicated that 16 h of supplementary light led to certain stresses in watermelon seedlings. In conclusion, considering the energy consumption, 12 h of supplementary light was the most efficient in improving the quality of the two cultivars of grafted watermelon plug seedlings.

A novel strain of endophytic Streptomyces for the biocontrol of strawberry anthracnose caused by Glomerella cingulata

Anthracnose caused by Glomerella cingulata is one of the most devastating diseases of strawberry in Japan, particularly during its nursery period in the summer. In this study, we aimed to isolate and screen endophytic actinobacteria, to identify potential biocontrol agents capable of suppressing strawberry anthracnose. A total of 226 actinobacteria were successfully isolated from surface-sterilized strawberry tissues. In the first screening, 217 out of 226 actinobacteria isolates were studied for their suppression effect on strawberry anthracnose using a detached leaflet assay. It was discovered that isolates MBFA-172 and MBFA-227 markedly suppressed the development of anthracnose lesions. The efficacy of both isolates was then tested on two-month-old strawberry plug seedlings in a controlled environmental chamber. It was found that isolate MBFA-172 provided consistent disease suppression and was thus selected as a final candidate for further evaluation in a glasshouse experiment. Results showed that the severity as well as incidence rate of strawberry anthracnose was significantly reduced by treatment with isolate MBFA-172 compared with that of untreated control. Accordingly, the disease control efficacy provided by MBFA-172 was statistically comparable to the chemical fungicide propineb. A re-isolation experiment using a spontaneous thiostrepton-resistant mutated strain of isolate MBFA-172 revealed that it efficiently colonized the above-ground tissues of strawberry plants for at least three weeks after spray treatment. Using cultural, morphological, and physiological tests combined with 16S rRNA-based molecular analysis, MBFA-172 was identified as a moderately thermophilic Streptomyces thermocarboxydus-related species. Upon review, our results strongly indicated that MBFA-172 is a promising biocontrol agent for strawberry anthracnose.

Design of a control system for a mini-automatic transplanting machine of plug seedling

In China, vegetable production system has been dominated by small and medium-sized agricultural facilities over the open-field cultivational practices. Low ceiling height and narrow width are dimensional attributes associated with most of these facilities. Due to these dimensional parametric constraints, the application of available field transplanting machinery in such facilities is a problematic subject which leads the vegetable growers towards manual transplanting. In order to meet the needs of small and medium-sized agricultural facilities for automatic vegetable transplanting, a smaller size wireless remote-controlled automatic transplanting machine was designed, which can transplant seedlings quickly in the greenhouse and by considering the stainability of environment electric power was adopted to drive all the mechanisms. In the process of agricultural production, the control system of agricultural machinery plays an important role in the degree of automation of mechanical equipment. Therefore, this paper focuses on the design of the control system of the newly premeditated automatic transplanting machine. The hardware of the control system is separated into three portions: the sensors for signal acquisition, the programmable controller for signal processing, and the driving elements for specific actions. PLC (Programmable logic controller) is adopted as the central control system of the transplanting machines which controls the automatic movement of seedlings tray carrier, seedlings extraction and feeding, and seedlings transmission to the planting units automatically. In order to control the overall movement of seedling transplanting machine, a microcontroller is adapted to control the hub and steering motor. The key driving elements of the control system are solenoid valves and electric motors which controls the action of pneumatic air cylinders and linear movement of different parts of machine respectively. The overall software design of the control system is accomplished, together with coordinated motion between components, control flow design and control program writing. In order to test the motion coordination of each component and the rationality of the control system of the Mini-Automatic transplanting machine, different planting frequencies were set to record the success rate of seedling collection and transplanting. The results of the trials exhibited that at the planting frequencies of 40, 50 and 60 plants/row/min the overall success rates were noted 98.6%, 97.2% and 96.5% respectively. It shows that the key parts of the transplanting machine are synchronized in motion, accurate in positioning, reasonable in assembling the control system and stable in operation, which meets the requirements of transplanting seedlings in the dry land.

Biometric Properties of Plug Vegetable Seedlings Relevant to the Design of Vegetable Transplanter

In the present study, biometric properties of chilli (Pusa Jwala) and tomato (Abhilash) plug seedlings of 30-, 45- and 60-day old relevant to design of vegetable transplanter were investigated. The parameters determined were weight, stem diameter, height, critical canopy diameter, drop shatter height, compressive strength and coefficient of static friction of the plug seedlings. The average weight of chilli seedlings was 13.1, 15.2 and 15.9 g for 30-, 45- and 60-day old, respectively; whereas, that for tomato seedling was 13.4, 14.1 and 14.5 g for 30-, 45- and 60-day old, respectively. The optimum drop shatter height with minimum shattering of plug media for both seedlings was 400 mm. The critical canopy diameter for chilli and tomato seedling was 68.2 mm and 70.4 mm, respectively. The mean coefficient of static friction for canvas belt, mild steel, aluminium and galvanized iron varied from 0.63 to 0.89. The compressive strength of stem of seedlings ranged from 1.2 kgf to 1.6 kgf. These properties of vegetable seedlings are critical in designing and selection of different components of vegetable transplanter.

Biometric Properties of Plug Vegetable Seedlings Relevant to the Design of Vegetable Transplanter

In the present study, biometric properties of chilli (Pusa Jwala) and tomato (Abhilash) plug seedlings of 30-, 45- and 60-day old relevant to design of vegetable transplanter were investigated. The parameters determined were weight, stem diameter, height, critical canopy diameter, drop shatter height, compressive strength and coefficient of static friction of the plug seedlings. The average weight of chilli seedlings was 13.1, 15.2 and 15.9 g for 30-, 45- and 60-day old, respectively; whereas, that for tomato seedling was 13.4, 14.1 and 14.5 g for 30-, 45- and 60-day old, respectively. The optimum drop shatter height with minimum shattering of plug media for both seedlings was 400 mm. The critical canopy diameter for chilli and tomato seedling was 68.2 mm and 70.4 mm, respectively. The mean coefficient of static friction for canvas belt, mild steel, aluminium and galvanized iron varied from 0.63 to 0.89. The compressive strength of stem of seedlings ranged from 1.2 kgf to 1.6 kgf. These properties of vegetable seedlings are critical in designing and selection of different components of vegetable transplanter.

Trajectory planning and motion control of full-row seedling pick-up arm

Frequent start-stops of automatic seedling transplanters would lengthen the seedling picking time due to alternating movement of the motor, and cause positioning errors and frequent motor vibrations when starting the machine. To solve these problems and ensure the pick-up continuity of automatic transplanters, in this study the smooth circular arc interpolation algorithm and the least square method for multinomial curve fitting were used to conduct the trajectory planning of automatic transplanter based on the movement of the pick-up arm of the transplanter. Velocity and time curves were fitted in segments to acquire motion control parameters and further tracking control was conducted. The mathematical model of the control system was established using Simulink, and simulation analysis and system debugging test were performed. Experiments show that the trajectory curves obtained by MATLAB’s data processing can realize the continual and smooth motion trajectory of the pick-up arm; stepper motor velocity control can effectively track the planning curve and improve the seedling pick-up efficiency. The pick-up and pushing time of each motion of the planned plug seedling transplanter reduced by 1.0678 s and the start-stop times reduced from 6 to 1, which solved the frequent motor vibrations when starting the machine and improved the stability of the system. In addition, overstep and out-of-step of the motor at the start-stop moment were avoided and displacement error was reduced. Keywords: trajectory planning, motion control, motion trajectory simulation, transplanter, stepper positioning DOI: 10.25165/j.ijabe.20201303.5264 Citation: Ren L, Wang N, Cao W B, Li J Q, Ye X C. Trajectory planning and motion control of full-row seedling pick-up arm. Int J Agric & Biol Eng, 2020; 13(3): 41–51.