Tomato Plug Seedlings Research Articles

Does the Daily Light Integral Influence the Sowing Density of Tomato Plug Seedlings in a Controlled Environment?

To achieve high-density tomato seedlings in a plant factory with artificial lighting, tomatoes (Solanum lycopersicum Mill. cv. “Zhongza NO.9”) were used as the experimental material. This study expected to analyze the effects of light intensity (150, 200, 250, and 300 μmol·m−2·s−1) and light time (12 and 14 h), as well as daily light integral (DLI, 10.80, 12.60, and 12.96 mol·m−2·d−1) and sowing density (50, 72, and 105 holes per tray), on seedling quality. The results indicated that biomass accumulation, seedling quality, and energy use efficiency of seedlings significantly improved with an increase in DLI. At a DLI of 12.96 mol·m−2·d−1, seedlings sown at a density of 72 holes per tray exhibited comparable growth characteristics and biomass accumulation to those sown at 50 holes per tray. However, under lower DLIs, seedlings at 50 holes per tray displayed superior growth morphology and seedling quality compared to those at 72 holes per tray. This indicates that increasing the DLI can partially mitigate the negative effects of higher sowing density on seedling quality. Light use efficiency (LUE) and energy use efficiency (EUE) were not significantly different between seedlings at 72 and 105 holes per tray but were higher than those at 50 holes per tray. Therefore, optimizing parameters such as DLI and sowing density can effectively enhance the seedling quality, spatial use efficiency, and light use efficiency in industrial seedling production. Based on the results of this study, a DLI of 12.96 mol·m−2·d−1 (achieved with a light intensity of 300 μmol·m−2·s−1 and a light time of 12 h) and sowing density of 72 holes per tray are recommended for cultivating high-quality tomato seedlings while reducing energy consumption.

Transient multi-indicator detection for seedling sorting in high-speed transplanting based on a lightweight model

Quality sorting of plug seedlings is an important part of factory nurseries, and deep learning is starting to become a core technology in this field. In response to the key problems of existing sorting systems with a single perspective and insufficient detection indicators, this paper innovatively proposes a lightweight multi-indicator detection model for plug seedlings, and an integrated transient sorting system for high-speed transplanting is designed. The new YOLOv5s model is composed of the ShuffleNet-V2 backbone, a channel attention mechanism neck, and a head block, and it can effectively extract image features of different seedling qualities. We built a dataset for pepper and tomato plug seedlings, and the experimental results showed that the model was highly accurate in detecting no seedlings, weak seedlings, damaged seedlings and strong seedlings, with an mAP of 94.23 %. Finally, in the verification of different operating speeds, the transplanting-sorting-replanting multifunctional system had the best integrated efficiency of 4200 plants per hour, and the average treatment time for single plug seedlings was only 0.86 s. Our method effectively can improve the performance of seedling quality sorting systems and provide technical support for factory nurseries.

Information Acquisition Method of Tomato Plug Seedlings Based on Cycle-Consistent Adversarial Network

In order to solve the interference caused by the overlapping and extrusion of adjacent plug seedlings, accurately obtain the information of tomato plug seedlings, and improve the transplanting effect of automatic tomato transplanters, this study proposes a seedling information acquisition method based on Cycle-Consistent Adversarial Network (CycleGAN). CycleGAN is a generative unsupervised deep learning method, which can realize the free conversion of the source-domain plug seedling image and the target-domain plug label image. It collects more than 500 images of tomato plug seedlings in different growth stages as a collection image set; follows certain principles to label the plug seedling images to obtain a label image set, and uses two image sets to train the CycleGAN network model. Finally, the trained model is used to process the images of tomato plug seedlings to obtain their label images. According to the labeling principle, the correct rate of model recognition is between 91% and 97%. The recognition results show that the CycleGAN model can recognize and judge whether the seedlings affected by the adjacent seedling holes are suitable for transplanting, so the application of this method can greatly improve the intelligence level of the automatic tomato transplanters.

Effect of Bacillus methylotrophicus on Tomato Plug Seedling

Tomato production is gradually shifting to modern production, which requires the factorization of tomato seedlings to shorten the seedling cycle and improve the seedling quality. Bacillus methylotrophicus, as a biofertilizer for plant growth-promoting rhizobacteria, can promote plant growth and enhance native plant defenses. However, reports on the role of this type of bacterial agent in horticultural crop seedlings are limited. We investigated the effects of different dosages of Bacillus methylotrophicus (0.00, 0.25, 0.50, 0.75, 1.00, 1.25, and 1.50 g/strain) on tomato plug seedlings and aimed to screen out the suitable dosage of Bacillus methylotrophicus for tomato seedlings in 50-hole cavity trays. In this experiment, with the increase in Bacillus methylotrophicus, the number of leaves, plant height, stem thickness, leaf area, dry matter accumulation in each organ, growth function (G value), and seedling strength index of tomato seedlings showed an increasing trend, followed by a decreasing one. The appropriate dosage (0.50–1.25 g/strain) of bacterial agent increased the activities of the substrates urease, sucrase, and catalase, thus forming a good microbial community to maintain the balance of organic and inorganic carbon and guaranteeing the normal development of the root system. Meanwhile, under the treatment of 1.00 and 1.25 g/strain of inoculum, the absorption range of tomato roots increased, more nitrogen, phosphorus, and potassium were absorbed from the substrate, and more nutrients were transported from the underground to the above-ground parts, which promoted shoot elongation and thickening of the shoots, increased the leaf number and dry matter accumulation, and improved the seedling quality. In this study, the mechanism of action of this microbial product on tomato seedlings was studied from the perspective of nutrient uptake and supply, and a sowing root application of 1.00 g/strain of Bacillus methylotrophicus in 50-hole cavity trays can improve the quality of tomato seedlings.

Effects of Biochar Addition into Substrate on Tomato Plug Seedlings and Its Working with Automatic Transplanting

Vegetable seedling transplantation has become a beneficial and specialized procedure, and a vegetable-specific study on seedling qualities for compatibility with automatic transplanting is needed. In this study, biochar prepared from corn straws was used as the auxiliary material to cultivate seedlings. Firstly, physicochemical properties of compound substrates with different composite of biochar (volume ratio 0, 10, 20~50%) and growth indices of seedlings were measured according to agpronomic conditions. Then, mechanical properties of root lumps and transplanting integrity were investigated. Finally, the optimal seedling qualities for automation of seedling transplanting were comprehensively evaluated with Technique for Order Preference by Similarity to Ideal Solution (TOPSIS). In the results, the rich porous structure and surface area of corn straw biochar can regulate the physicochemical properties of the matrix, which significantly affected the growth of seedling roots and plants. The biochar addition of 10% and 20% in volume ratios was beneficial to the root formation and plant growth. More than 30% biochar-treated substrates had a tendency to inhibit seedling growth. Under the same seedling conditions, the appropriate addition of biochar can improve the twisting strength of root lumps and prevent axial deformation. In conclusion, the comprehensive evaluation coefficient of addition with 10% biochar was 0.67, which was significantly higher than other treatments. Under this treatment, tomato seedlings were stockily grown with rich roots, and the integrity rate of automatic transplanting was above 96%. The biochar of corn straws may be an effective application for the necessary qualities of seedlings for automatic transplanting.

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

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.

Optimizing basket transplanting parameters using the mechanical properties of tomato plug seedlings

The collision between tomato plug seedlings and the planting device during basket transplanter function causes the seedlings’ root lump to lose some mass. To resolve this problem, we establish a contact mechanics model using Hertzian contact theoretical and Newtonian methods, enabling us to formally derive the maximum deformation of the root lump. The equation of motion describing the collision between the tomato plug seedling and planting device is constructed using the principles of impulse and momentum. Then, we identify the optimization function of contact angle θ—which consists of the maximum deformation of the root lump, the angular velocity of the tomato plug seedling, and the absolute velocity of the root lump—via multi-objective methods. When the angular velocity of the planting device is 1.05 rad/s or 1.15 rad/s, the optimal contact angle is 67°. Further, we examine the velocity of the tomato plug seedling after collision. A small plant height reduces the root lump’s mass loss; we found that 12-cm-tall tomato plug seedlings lose less root lump mass than taller seedlings. Finally, for angular velocities of 1.05 rad/s and 1.15 rad/s, we carry out of tomato plug seedling crush tests with the optimized parameters, achieving minimum root lump mass losses of 8.76% and 7.43%, respectively.

The Growth and Development of ‘Mini Chal’ Tomato Plug Seedlings Grown under Monochromatic or Combined Red and Blue Light-Emitting Diodes

This study was conducted to examine the effects of monochromatic or combined LEDs lighting on the growth and development of tomato plug seedlings. ‘Mini Chal’ tomato (Solanum lycopersicum L.) seedlings were grown under diniconazole or various light quality treatments [fluorescent lamp (FL), 150 mg·L-1 diniconazole treatment under FL (Dini), and combination of red (R) and blue (B) LEDs as follows: R:B = 100:0 (R), R:B = 70:30 (R7B3), R:B = 50:50 (R5B5), R:B = 30:70 (R3B7), or R:B = 0:100 (B)] for 23 days. Combined R and B lighting resulted in shorter plants except for Dini, and monochromatic or combined LEDs lighting led to thickened stems than Dini. High R light environments resulted in the highest number of leaves. The leaf area was lower for plants in all LEDs environments and Dini compared to plants in FL. Dini and all LEDs environments except B increased the leaf thickness, with the thickest leaves observed for seedlings in R3B7 among LEDs treatments. The fresh and dry weights were the highest for plants in R and R3B7, respectively. Dini, R5B5, and R3B7 slightly increased the dry matter of plants. Combined LEDs environments increased the compactness, with R3B7 resulting in the largest increase. After transplanting to hydroponics culture systems, combined LEDs lighting induced accelerated flowering of the first and second clusters. In conclusion, the results of this study suggest that R3B7 is the most suitable light environment to produce high-quality ‘Mini Chal’ tomato plug seedlings.

The Growth and Development of ‘Mini Chal’ Tomato Plug Seedlings Grown under Various Wavelengths Using Light Emitting Diodes

This study aimed to determine the effects of various light qualities (green (G), ultraviolet-A (UV-A), and far-red (Fr)) on the growth and development of tomato plug seedlings. The ‘Mini Chal’ tomato (Solanum lycopersicum L.) seedlings were used as the plant material to which various light qualities were supplied. Fluorescent lamp (FL), combined FL and diniconazole (Dini), and R3B7 (red (R):blue (B) = 30:70) were used as the control. The different light treatments for this experiment were as follows: two G light ratios added to R3B7 (G20 and G40), three UV-A light intensities added to R3B7 (UV 0.4, UV 0.6, and UV 0.8), and three Fr light ratios added to R3B7 (Fr1, Fr2, and Fr3). Plants grown in UV 0.4 and Dini were the shortest, followed by plants grown in R3B7. R3B7 induced higher specific leaf weight than G, UV-A, and Fr did. The position of the first flower cluster was the highest for plants in FL and Fr1, and the lowest for plants in R3B7 and UV 0.6. In conclusion, different light treatments heavily affected the growth and development of ‘Mini Chal’ tomato seedlings. R3B7 was the most effective light treatment for producing high quality seedlings in a closed-type plant production system that develop well after transplanting.

Height Suppression of Cucumber and Tomato Plug Seedlings Using of Brushing Stimulus

Height Suppression of Cucumber and Tomato Plug Seedlings Using of Brushing Stimulus

Storage of plug seedlings of tomato under limited fertilisation, and growth, flowering and yield after planting

ABSTRACTWe stored plug seedlings of tomato (Solanum lycopersicum L. cv. Momotaro) under limited fertilisation (LF) for 12 weeks, and evaluated growth and development during storage and after planting. Seedlings in the LF treatment were grown in substrate containing starter fertiliser and irrigated with water. Controls (CT) were irrigated with nutrient solution. Stem growth, leaf growth, and biomass accumulation slowed or ceased during storage of LF seedlings, while CT seedlings showed increases in these parameters. At 2 weeks after planting, the stem length of LF seedlings was shorter than that of CT seedlings, but the two seedling types had similar numbers of leaves. At harvest, LF and CT plants had similar numbers of leaves under the fruit trusses, but the trusses formed at lower heights in LF than in CT seedlings. LF and CT plants produced similar numbers of fruits and similar yields from the first to third trusses. These results indicate that tomato plug seedlings can be stored for more than 2 months under LF.

Effect of Physical Properties of Medium and Its Water Distribution on Uniform Emergence of Tomato Plug Seedlings

Effect of Physical Properties of Medium and Its Water Distribution on Uniform Emergence of Tomato Plug Seedlings

Physicochemical Properties of Newly Developed Artificial Medium and Proper Irrigation Interval for Production of Tomato Plug Seedlings

Physicochemical Properties of Newly Developed Artificial Medium and Proper Irrigation Interval for Production of Tomato Plug Seedlings

Determination of the Optimal Nitrogen Concentration in Pre-planting Fertilizers for the Cultivation of Tomato Plug Seedlings

Determination of the Optimal Nitrogen Concentration in Pre-planting Fertilizers for the Cultivation of Tomato Plug Seedlings

Impact of Pre-planting NO3:NH4 Ratios in Root Media on the Growth of Tomato Plug Seedlings

Impact of Pre-planting NO3:NH4 Ratios in Root Media on the Growth of Tomato Plug Seedlings

Use of Pellet or Cube-type Phenolic Foam as an Artificial Medium for Production of Tomato Plug Seedlings

Use of Pellet or Cube-type Phenolic Foam as an Artificial Medium for Production of Tomato Plug Seedlings

Effect of Water Content in the Substrate of the Scion and Rootstock during Pre- and Post-Grafting Period on the Survival Rate and Quality of Tomato Plug Seedlings

This study evaluated the effect of water content in the substrate during pre- and post-grafting period on the survival rate and quality of tomato plug seedlings. Nine combinations of three water levels (high, medium, and low) were set up in the substrate of both scion and rootstock. The water content in the substrate of the scion did not affect the survival rate of grafted tomato seedlings, while the survival rate was statically different among the various water contents in the substrate of the rootstock. The maximum survival rates (100%) were observed in seedlings treated with high water levels in the substrate of the rootstock, and the survival rates declined with decreasing water content in the rootstock substrate. The growth characteristics were not significantly affected by different water content in the scion substrate, while they were statically different among the seedlings treated with various water contents in the rootstock substrate. The growth characteristics decreased with decreasing water content in the rootstock substrate. The highest value of compactness was observed in grafted seedlings, which combined medium water level in the scion and high water level in the rootstock substrate treatment. The root morphology of tomato seedlings was also affected by water content in the rootstock substrate. The total root surface area, total root length, and number of root tips decreased with deceasing water content in the rootstock substrate.

番茄穴盘苗组织钾阈值的初步研究

为明确番茄穴盘苗组织钾阈值，采用四苯硼钠比浊法测定了番茄17个主栽品种不同组织钾含量，并选其中两个品种(佳红4号和中杂105号)研究了氮、磷、钾盈亏供应和外界环境因素对番茄穴盘苗组织钾含量的影响。发现17个品种中，仙客5号组织间钾含量的变化范围最大，为2.92~6.72 g/L；供试品种的10个取样组织中，第2叶位叶柄品种间钾含量的变化范围最大，为3.23~4.93 g/L。与正常对照相比，钾盈余供应下番茄穴盘苗组织钾含量最大提高了1.23倍，钾亏缺供应下钾含量最大减小了64.84%。番茄穴盘苗组织钾含量也会因氮供应水平、磷供应水平、温度、光照等外部因素的改变而变化，最大增加了38.34%，最大减小了36.01%。以番茄17个品种不同组织钾含量范围为基础阈值，利用环境条件作用最大增幅和最大减幅进行校正，获得番茄穴盘苗组织钾含量阈值，即下胚轴4.63~6.94 g/L，茎5.56~7.40 g/L，第1叶位叶柄2.65~4.62 g/L，第1叶位叶片2.14~4.09 g/L，第2叶位叶柄2.80~6.93 g/L，第2叶位叶片2.54~5.17 g/L，第3叶位叶柄3.55~7.06 g/L，第3叶位叶片2.69~6.24 g/L，第4叶位叶柄4.29~7.71 g/L，第4叶位叶片3.90~7.07 g/L。 To obtain the K threshold in tissues of tomato plug seedlings, K contents were measured in different tissues of 17 tomato cultivars by turbidimetric method with sodium tetraphenylborate. The effects of N, P, K fertilization level and environmental factors on K contents were also examined in two representative cultivars (“Jiahong No.4” and “Zhongza No.105”). The results showed that K contents varied among different cultivars and tissues with significant difference. The K threshold of the second leaf petiole among different tissues was maximal and 3.23 - 4.93 g/L, and the K threshold of Xianke No.5 among different tissues was maximal and 2.92 - 6.72 g/L. In addition, the K contents of tomato plug seedlings increased as the K fertilization levels increased from 29 to 1875 mg/L. Compared to that in the seedlings supplied with normal K, the K content was increased by at most 1.23-fold in the seedlings supplied with excessive K, while in the seedlings fertilized with low level of K, the K content was reduced at most 64.84%. With the change of external factors such as N or P fertilization level, or temperature, or light intensity, the K contents in tissues of tomato plug seedlings also changed. And the K contents were increased at most 38.34% and decreased at most 36.01%. Therefore, the basic values of K contents from 17 cultivars were corrected with these environmental factors. Finally the K threshold in tissues of tomato plug seedlings was 4.63 - 6.94 g/L in hypocotyls, 5.56 - 7.40 g/L in stems, 2.65 - 4.62 g/L in first leaf petioles, 2.14 - 4.09 g/L in first leaves, 2.80 - 6.93 g/L in second leaf petioles, 2.54 - 5.17 g/L in second leaves, 3.55 - 7.06 g/L in third leaf petioles, 2.69 - 6.24 g/L in third leaves, 4.29 - 7.71 g/L in fourth leaf petioles, 3.90 - 7.07 g/L in fourth leaves.