Tomato Fruit Research Articles

Comparison of fruit and quality parameters of tomato and capsicum by using different amount of nano ZnO through foliar and seed application

Selecting the appropriate dosage of nano zinc oxide for tomato and capsicum plants is crucial since higher concentration may negatively impact crop productivity and quality. Maintaining soil health helps in increasing crop output and quality without degrading the soil from overfertilization. The main objective of the study was to determine the physiological responses of both crops and ideal dose of nano zinc oxide (ZnO) for yield maximization and quality enhancement under controlled conditions. In present study, nano ZnO had noticeable effect on the fruit and quality parameters of both Solanaceous crops. Plants were treated with seed treatment and foliar applications of nano ZnO @ 50, 100, and 150 parts per million (ppm) along with 100% recommended dose of nutrients (RDN) through vermicompost; and 100% RDN through integration of vermicompost and fertilizers. In addition, nano zinc oxide was not supplied to the control treatment plants (T1). The results of the study revealed that 50 ppm of nano ZnO as foliar spray increased fruit and quality parameters in tomato and capsicum. In case of protein content, treatment comprised of 50 ppm of nano ZnO as seed treatment + 100% RDN through vermicompost and fertilizers, produced higher protein content over control. Furthermore, the application of nano ZnO lowered ascorbic acid levels in tomato and capsicum, while the control had the greatest levels. These results suggested that lower concentration of ZnO nanoparticles (50 ppm) is an ideal dosage and could be used in tomato and capsicum cultivation to improve yield and quality indices.

Adjusting Irrigation and Phosphate Fertilizer to Optimize Tomato Growth and Production

The efficient use of phosphate fertilizers and optimization of the amounts of irrigation water can maximize tomato growth and fruit production. This study aimed to evaluate the effects of different phosphorus (P) doses and sources on the growth and production components of tomato plants of the cultivar Gaúcho Melhorado Nova Seleção subjected to different irrigation water percentages. To achieve this, we set up an experiment using a factorial design to test the effects of four doses of P2O5 (corresponding to 25%, 50%, 100%, and 200% of the recommended dose), two P sources (monoammonium phosphate—MAP and organomineral—OM), and four irrigation water percentages (50%, 75%, 100%, and 125% of field capacity). Tomato plant growth improved when water was supplied at a percentage close to 100% of field capacity, with increased plant height, leaf length, and number of flowers observed (increases of 11.95%, 7.33%, and 13.87%, respectively, compared to 50% of field capacity). However, both excess and deficit irrigation resulted in morphological changes in tomato plants. Additionally, we observed that OM was more effective than MAP in increasing plant diameter and number of flowers, with increases of up to 36.4% and 227.6%, respectively, when using OM. Conversely, tomato growth was negatively affected by higher doses of MAP doses, suggesting that 25% of the recommended dose may yield the best growth rates. We verified that tomato plants can compensate for low phosphorus doses by increasing productivity with higher water amounts (125%–42.40 t ha−1), but high phosphorus doses result in greater fruit production with lower water percentages (50%–41.52 t ha−1).

Research on Multi-Step Fruit Color Prediction Model of Tomato in Solar Greenhouse Based on Time Series Data

Color change is the most obvious characteristic of the tomato ripening stage and an important indicator of the tomato ripening condition, which directly affects the commodity value of tomato. To visualize the color change of tomato fruit during the mature stage, this paper proposes a gated recurrent unit network with an encoder–decoder structure. This structure dynamically simulates the growth and development of tomatoes using time-dependent lines, incorporating real-time information such as tomato color and shape. Firstly, the .json file was converted into a mask.png file, the tomato mask was extracted, and the tomato was separated from the complex background environment, thus successfully constructing the tomato growth and development dataset. The experimental results showed that for the gated recurrent unit network with the encoder–decoder structure proposed, when the hidden layer number was 1 and hidden layer number was 512, a high consistency and similarity between the model predicted image sequence and the actual growth and development image sequence was realized, and the structural similarity index measure was 0.746. It was proved that when the average temperature was 24.93 °C, the average soil temperature was 24.06 °C, and the average light intensity was 11.26 Klux, the environment was the most suitable for tomato growth. The environmental data-driven tomato growth model was constructed to explore the growth status of tomato under different environmental conditions, and thus, to understand the growth status of tomato in time. This study provides a theoretical foundation for determining the optimal greenhouse environmental conditions to achieve tomato maturity and it offers recommendations for investigating the growth cycle of tomatoes, as well as technical assistance for standardized cultivation in solar greenhouses.

Nutritional quality of tomato in response to different fertilization doses and conduction systems

The tomato, a rich source of essential nutrients such as vitamins A and C, potassium, and antioxidants, plays a crucial role in human nutrition, promoting health and preventing diseases. In Brazil, its production is vital, involving significant resources and labor. The correct nutritional management of the crop can improve the nutritional attributes of tomato fruits, therefore the correct use of fertilizers is of great importance due to the high need for phosphorus, nitrogen and potassium, throughout the crop cycle. Nutritional management is of great importance in tomato fields due to its high fertilizer requirements throughout the entire crop cycle. This study aimed to assess the effect of different fertilizer doses and management systems on the physicochemical characteristics of tomatoes. The experiment followed a factorial design with five fertilizer doses (A0: 0%; A1: 50%; A2: 100%; A3: 150%; A4: 200% of the recommended dose) and four conduction systems, with three replications. Productivity, lycopene content, total soluble solids (TSS), nitrogen, phosphorus, potassium, calcium and magnesium fruit contents were evaluated. The results showed that higher fertilizer doses increased lycopene levels, reaching 80 μg g-1 with 200% fertilization, while 0% provided 30 μg g-1. Total soluble solids above 4°Bx were observed at doses above 150%, regardless of planting density. Nitrogen content reached 26 mg·100 g-1f.m., favored by lower densities. Calcium was influenced by fertilizer doses, with higher concentrations at 150%. In conclusion, the application of 150% fertilizer dose improved the nutritional quality of tomatoes, and the 200% dose provided suitable levels of TSS and lycopene for processing.

Composite Coatings with Liposomes of Melissa officinalis Extract for Extending Tomato Shelf Life

In this study, active coatings based on carboxymethylcellulose (CMC) were prepared using liposomes filled with an aqueous extract of Melissa officinalis retained in high acyl gellan gum (HAG), low acyl gellan gum (LAG), and their mixture (HAG/LAG). The objective was to investigate the effect of these coatings on postharvest preservation of tomato (Solanum lycopersicum) fruits. The tomato fruits were divided into four groups: (i) coating with HAG-based liposomes (WL-HAG), (ii) coating with LAG-based liposomes (WL-LAG), (iii) coating with HAG/LAG-based liposomes (WL-HAG/LAG), and (iv) control group treated with sterile water. Over a period of 10 days, various quality attributes, such as respiration rate, soluble solids, titratable acidity, luminosity, weight loss, malondialdehyde (MDA) content, hydrogen peroxide, total phenols, and DPPH scavenging ability, were studied. The results indicated that the WL-HAG coatings significantly (p < 0.05) decreased the respiration rate, hydrogen peroxide, and MDA content compared to the control fruits and other coatings. Therefore, WL-HAG could be considered a promising option to enhance postharvest preservation of tomato fruits in the Colombian fruit and vegetable industry.

Dissipation and dietary risk assessment of fluoxapiprolin (and its metabolites) residues in cucumber and tomato samples under field conditions

The present study was undertaken to understand the dissipation behaviour/kinetics of fluoxapiprolin and its metabolites in cucumber and tomato under field conditions. A QuEChERS based extraction method followed by liquid chromatography coupled to mass spectrometry (LC-MS/MS) analysis showed that all method validation parameters were within the acceptable range as per international standards with a limit of quantitation (LOQ) of 0.01 mg kg−1 for all analytes. As significant matrix effects were observed with a few metabolites, matrix matched standards were used for the whole study. Residues of fluoxapiprolin in cucumber at standard dose were steady from 0 to 3 day after application and were below LOQ on the 5th day after application. In cucumber fruit at double dose and in tomato at both the doses the residues followed second-order kinetics and were respectively ≤ LOQ from days 7 and 14 onwards. Pre-harvest intervals (PHI) of 5 days and 14 days are proposed for cucumber and tomato fruits respectively. All the metabolites were ≤ LOQ from day 0 in all the matrices. The consumer risk, assessed as Hazard Quotient (HQ), showed that HQ was ≤1 in all the cases. The results of the present study and earlier studies on other similar fungicides suggest that the use of fluoxapiprolin in cucumber and tomato fruits may not pose health or environmental hazards provided that good agricultural practices are followed and the proposed waiting period is observed. The data from the present study can be used by regulatory bodies in establishing maximum residue limits.

Impact of Storage Conditions on Fruit Color, Firmness and Total Soluble Solids of Hydroponic Tomatoes Grown at Different Salinity Levels

Tomatoes are delicate and prone to damage quickly, which ultimately leads to lower quality and increased post-harvest losses. Hence, an ideal storage environment is very important to maintain the quality of tomato fruits after harvest. Therefore, this study was conducted to determine the effect of storage conditions on the quality parameters of tomato fruits. Experiments were de-signed for six storage periods (4, 8, 12, 16, 20, and 24 days) and two temperatures (12 °C and room air temperature “22 °C”). Three tomato fruit quality parameters (Brix, color, and firmness) have been selected and measured for three tomato varieties (Ghandowra-F1, Forester-F1, and Feisty-Red) grown hydroponically at three salinity levels (2.5, 6.0, and 9.5 dS m−1) of the nutrient solution. Results showed that the highest mean Brix values, for all varieties, were recorded at the highest salinity (9.5 dS m−1), and were significantly (Pr < 0.0001) higher than those at medium (6.0 dS m−1) and low (2.5 dS m−1) salinity levels. In addition, the highest fruit firmness was recorded at high salinity level (9.5 dS m−1), but there was no significant difference to that recorded at medium salinity (6.0 dS m−1). Regarding tomato fruit color, the highest average values were recorded for the Ghandowra-F1 (2.51) and Forester-F1 (2.69) varieties at medium salinity (6.0 dS m−1), while the highest average color value for the Feisty-Red variety (1.54) was obtained at high salinity (9.5 dS m−1). On the other hand, the Brix, color, and firmness of tomato fruits were significantly affected by the storage temperature. Moreover, the mean Brix values (7.66%) were slightly higher at 12 °C storage temperature compared to those at 22 °C (7.38%). In general, the fruit color values gradually increased with the storage period, especially under 22 °C storage temperature, with peak color values of 2.73, 2.70, and 1.66 recorded on the 12th day of the storage period for Ghandowra-F1, Forester-F1, and Feisty-Red, respectively. Tomato fruit firmness decreased faster with the storage period at 22 °C compared to the storage temperature of 12 °C. However, the highest average values of fruit firmness for Ghandowra-F1 (9.37 N cm−1) and Forester-F1 (9.41 N cm−1) recorded at control condition were not significantly different those recorded on the 8th day of storage at 12 °C storage temperature. By contrast, the highest average value of fruit firmness for Feisty-Red (8.85 N cm−1) recorded at control condition was not significant than that recorded on the 4th day of the storage period at 12 °C storage temperature (8.82 N cm−1). Overall, tomato fruits can be stored at 12 °C temperature for up to 20–24 days, without negative effects on fruit quality.

Evaluation of Intercropping and Tobacco Leaf Extract for Management of Fruit Borer (Helicoverpa armigera) and Some Associated Beneficial Insects on Tomato in Eastern Hararghe, Ethiopia

Tomato production is challenged by different insect pests among these, fruit borer is the most destructing pests of tomato. To tackle these problems, the study was initiated with the objective to evaluate intercropping and tobacco extract on fruit borer and some associated beneficial insects on tomato in Eastern Hararghe. Head cabbage, common bean, onion, tobacco leaf extract and karate were used as treatments. The experiment was laid out in RCBD with four replications. From these results, significant differences were observed between treatments on larval population per plant and infestation per plant for all insect pests tested and also in population reduction. Tobacco leaf extract highly reduced the population occurrence and infestation level of fruit borer next to karate and followed by onion intercropping. The number of branches, number of fruits, and number of damaged fruits, marketable yield, non-marketable yield, and total yield also showed a significant difference (P < 0.05) among the treatments. The number of fruits per plant, marketable yield, and Total yield were the highest on onion intercrops followed by karate and tobacco extracts whereas the lowest number was observed from head cabbage intercrops. Maximum yield and yield traits were recorded on tomato onion intercropping compared to the rests of intercrops while the botanical extract comparably maximized the yields with Karate. Therefore, tomato-onion intercropping and tobacco leaf extract were used as the best alternatives to karate, the synthetic insecticides in the management of tomato fruit borer.

Genetic diversity and population structure of a modified three-way tomato hybrids for determining fruit size traits

The assessment of genetic diversity and genetic structure of crops has a vital impact on the plant breeding program, including the characterization, use and conservation of genetic material. The genetic diversity and genetic structure of a set of 94 F3 tomato hybrids were assessed with 25 polymorphic SNP markers of quantitative trait loci (QTLs) underlying fruit size in tomatoes using Sequenom Mass ARRAY system. A total of 50 alleles were amplified and the average polymorphic information content (PIC) was 0.2220. Nei's genetic distance ranged from 0 to 0.62. Therefore, single nucleotide sequence (SNP) markers detected a significantly high degree of polymorphism in tomato hybrids. Cluster analysis using the unweighted pair group method with arithmetic mean methods (UPMA) indicated that the tomato hybrids studied are grouped into four main groups, which is to some extent consistent with the size, shape and number of locules of the tomatoes studied. Analysis of population structure with SNP markers revealed three subpopulations. Association mapping using 25 SNP markers detected 9 markers with a significant association with mean fruit weight, fruit length, fruit diameter, number of locules, and fruit shape index. The nine markers detected in this study are recommended for the tomato fruit size improvement breeding program.

Effect of Introgression of Ty-1 and ty-5 Genes on Productivity, Quality, and Antioxidant Compounds in De la Pera Tomato Breeding Lines

Tomato (Solanum lycopersicum L.) is a crop that is affected by more than a hundred viral species. De la pera is a local varietal type of tomato that is very popular in southeastern Spain. However, it is highly susceptible to several viruses, such as Tomato yellow leaf curl virus (TYLCV), which is considered one of the most important diseases of tomato crops and is a limiting factor for production in both outdoor and protected crops, making it difficult to eradicate. This study shows the effect of gene introgression on the performance of traditional lines of De la pera by combining two genes that offer tolerance to TYLCV, Ty-1 and ty-5, on some yield and quality traits and on the antioxidant capacity of tomato fruits. Two pear tomato breeding families, UMH175 and UMH220, were evaluated. Four lines from each of the families with all homozygous combinations of the Ty-1 and ty-5 genes were studied. The results showed that the introgression of the ty-5 allele produced a slight negative effect on yield, mean fruit weight, total soluble solids, and titratable acidity, in contrast to Ty-1, which produced a large negative effect. None of the introgressions showed a negative effect on the antioxidant compounds. ty-5 is a promising gene for use in breeding programs.

Genome-wide identified VvOFP genes family and VvOFP4 functional characterization provide insight into fruit shape in grape

Ovate Family Proteins (OFPs) are emerging as novel transcriptional regulators of fruit shape. Despite their established role in various species, their involvement in regulating grape fruit shape remains understudied. This study encompassed a comprehensive evaluation of 16 grape OFP genes in total at the whole genome level. Phylogenetic and synteny analyses established a close relationship between grape VvOFP genes and their tomato counterparts. Expression profiling post-treatment with gibberellic acid (GA3) and thidiazuron (TDZ) revealed that certain OFP genes responded to these regulators, with VvOFP4 showing peak expression three days post-anthesis. Functional assays via overexpression of VvOFP4 in tobacco and tomato altered the morphology of both vegetative and reproductive organs, including leaves, stamens, and fruits/pods. Paraffin sections of transgenic tobacco stems and tomato fruits demonstrated that VvOFP4 overexpression modifies cell dimensions, leading to changes in organ morphology. Additionally, treatments with GA3 and TDZ similarly influenced the shape of grape pulp cells and thereby the overall fruit morphology. These findings suggest that the VvOFP4 gene plays a crucial role in fruit shape determination by modulating cell shape and presents a potential target for future grape breeding programs aimed at diversifying fruit shapes.

Vertical non-uniform distribution of soil salinity enhances nitrogen utilization efficiency and influences δ15N distribution in tomato plants

Soil salinity typically exhibits non-uniform distribution in the natural environment. However, how vertically non-uniform distribution of soil salinity in the root zone (VNDSR) regulated plant nitrogen metabolism is still largely elusive. This study aimed to investigate the impact of VNDSR on leaf Malondialdehyde (MDA) content, upper and lower root activity, leaf Na+/Ca2+ and Na+/K+, various tomato organs’ nitrogen concentration (%) and natural abundance of nitrogen isotopes (δ15N,‰), and nitrogen utilization efficiency of tomato plants. Four treatments were established, including the upper layer of the root zone having soil salinity levels of 1 ‰, 1 ‰, 2 ‰, and 3 ‰, while the corresponding lower layer of the root zone had soil salinity levels of 1 ‰, 5 ‰, 4 ‰, and 3 ‰, respectively, denoted as T1:1, T1:5, T2:4, and T3:3. The results showed that under the same average soil salinity conditions and compared to the treatment with uniform soil salinity distribution in the root zone (T3:3), the VNDSR treatment (T1:5) significantly reduced leaf MDA content (p < 0.01), Na+/Ca2+ (p < 0.01) and Na+/K+ (p < 0.01), and stem δ15N values (p < 0.05). Moreover, the VNDSR treatment (T1:5) significantly increased the ratio of upper and lower root biomass-weighted root activity (p < 0.01), tomato fruit yield (p < 0.01), and nitrogen partial factor productivity (PFP, gg−1, p < 0.01) compared to uniform salt distribution treatment (T3:3). There were significant positive correlations (p < 0.05) between leaf δ15N values and Nitrogen Absorption Ratio (NAR, %, p < 0.05) and PFP (p < 0.05), indicating that under VNDSR, δ15N values can serve as an indicator that comprehensively reflects the information of plant nitrogen utilization efficiency. In conclusion, the VNDSR could mitigate the damage of salt stress to tomatoes, enhance plant nitrogen uptake and utilization efficiency, and promote the growth and development of tomatoes. Data AvailabilityThe datasets generated or analyzed during the current study are available from the corresponding author on reasonable request.

Isolation and characterization of polygalacturonase producing thermophilic Aspergillus niger isolated from decayed tomato fruits

This study aimed to isolate a fungal strain capable of producing acidophilic and thermostable polygalacturonase. In this study, the fungal isolate was isolated from decaying tomatoes. Based on the colony characteristics, microscopic and morphological observations, the isolated fungal pathogen has been identified as Aspergillus niger. The isolated fungus was used in solid-state fermentation to produce an acidic polygalacturonase enzyme. The enzyme was then purified using ammonium sulphate precipitation and column chromatography, and its activity was assayed by measuring the releasing sugar group from citrus pectin using a 3, 5-dinitrosalicylic acid (DNSA) reagent assay. The crude extract obtained from solid-state fermentation had an activity of 94.6 U/mL. Ammonium sulphate precipitation increased the enzyme's specific activity from 6.89 U/mg to 12.42 U/mg. Sephadex G-200 was used to purify the enzyme 3.58 times, and its specific activity was determined to be 24.66 U/mg. The Sephacryl S-100 column achieved a final fold purification of 9.93 times and a specific activity of 68.41 U/mg. The purified enzyme performed best when polygalacturonic acid was used as a substrate. The enzyme's optimum temperature and pH were 55°C and 5, respectively. CaCl2 was found to be the best chelating ion for the enzyme. This enzyme is recommended for use in a variety of industrial applications as the enzyme was found to be stable at acidic pH and high temperature.

Chlorophyll content estimation and ripeness detection in tomato fruit based on NDVI from dual wavelength LiDAR point cloud data

Tomato (Solanum lycopersicum L.) is a climacteric fruit exhibiting the ripening pattern with change in colour from green to red. Normalized difference vegetation index (NDVI) derived from spectral-optical analysis has been previously employed in ripeness analysis of various fruits based on its strong correlation to ripening-related chlorophyll content. In this study, light detection and ranging (LiDAR) laser scanner was applied to gain 3D tomato point clouds aimed at estimating the spatially resolved chlorophyll content and ripeness class of tomato fruit. Freshly harvested tomatoes, capturing six ripeness classes (mature green, breaker, turning, pink, light red, and red) according to USDA colour standard, were analysed using a linear conveyor mounted sensor system consisting of two LiDAR units measuring position and return signal strength intensity at 660 nm and 905 nm. Fruit point clouds were pre-processed including geometric correction considering the curvature of each tomato sample, removing highest intensity areas at the specular highlighted spots, calibration of intensity values using standard black and white colour coated boards, and calibration on attenuation of the opaque samples. Particularly, for gaining the attenuation coefficient (μ), 9 opaque synthetic models with known attenuation were used. Obtained μ660 and μ905 were merged to gain NDVILiDAR. Chemically analysed chlorophyll content of tomato samples was correlated to μ660 and NDVILiDAR, whereas low correlation appeared for μ905 with a coefficient of determination (R2) of 0.58, 0.60, and 0.06, respectively. Regression models were used to estimate the total tomato chlorophyll content and the lowest root mean square error (RMSE) was found for μ660 (RMSE = 4.97 mg (100 g dry mass)−1) followed by NDVILiDAR (RMSE = 5.22 mg (100 g dry mass)−1), and μ905 (RMSE = 53.50 mg (100 g dry mass)−1). Histograms of NDVILiDAR and μ660 were extracted from each tomato point cloud and utilized to construct PLS-DA model for tomato ripening class prediction considering the spatial chlorophyll distribution. The overall accuracies for NDVILiDAR and μ660 were 70 % and 68 %, respectively, in leave-one-out cross-validation for visually defined colour classes. The LiDAR-based approach could support selective detection of ripe fruit in robots for harvesting and postharvest handling.

Investigation on the environmental causes of tomato fruit cracking and its propagation prediction in greenhouse.

In this study, Provence tomato variety was chosen for investigating the environmental causes of tomato fruit cracking, cracks characteristics, and their propagation prediction in a greenhouse. Fruit bagging approach was used to alter the temperature and humidity and to create a microclimate around the fruit to induce fruit cracking for testing. Results showed that the fruit cracking rate increased when the environment temperature exceeded 30°C, and the difference between the highest and lowest temperature values in a day was greater than 20°C. The cracking rate was aggravated when the difference between the highest and lowest humidity values in a day was less than 20%. The proportions of top cracking, longitudinal cracking, ring cracking, radial cracking, and combined cracking were 5.4%, 16.1%, 28.3%, 26.8%, and 32.1%, respectively. The fruit shoulder was the most susceptible region to crack, followed by fruit belly and top regions, whereas longer cracks were observed in the fruit belly region indicating a higher propensity to crack propagation in that region. Finally, the measured data were used to validate an extended finite element method developed to effectively predict cracking susceptibility and propagation in tomato fruit with a relative error of 4.68%.

Morphological and Molecular Characterization of the Pathogen Associated with Infected Leaf and Fruits of Tomato

This investigation describes the morpho-molecular characterization of the pathogen associated with infected leaf and fruits of tomato (Solanum lycopersicum L.). The fungal pathogen was identified based on their cultural morphology, microscopic features and analysis of Internal Transcribed Spacer (ITS) region sequences of nuclear ribosomal DNA (nrDNA). Cultural morphology including colour of the young and mature colony, growth pattern, concentric rings etc. and microscopic features including shape and size of microconidia, macroconidia, phialide, shape of apical and basal cells of macroconidia, septation in conidia, inter-septal distance and formation of chlamydospores corroborated the identity with the pathogenic fungi Fusarium oxysporum. The phylogenetic analysis based ITS regions sequences of nrDNA of the fungal isolate showed 100% identity with Fusarium oxysporum. Thus the ITS of nrDNA sequences validated the morphological data. Pathogenicity test also reconfirmed the identity of the test isolate of Fusarium oxysporum. The Chittagong Univ. J. B. Sci.,Vol. 10(1 &amp;2):31-40, 2020.

Dynamic Compressive Stress Relaxation Model of Tomato Fruit Based on Long Short-Term Memory Model.

Tomatoes are prone to mechanical damage due to improper gripping forces during automated harvest and postharvest processes. To reduce this damage, a dynamic viscoelastic model based on long short-term memory (LSTM) is proposed to fit the dynamic compression stress relaxation characteristics of the individual fruit. Furthermore, the classical stress relaxation models involved, the triple-element Maxwell and Caputo fractional derivative models, are compared with the LSTM model to validate its performance. Meanwhile, the LSTM and classical stress relaxation models are used to predict the stress relaxation characteristics of tomato fruit with different fruit sizes and compression positions. The results for the whole test dataset show that the LSTM model achieves a RMSE of 2.829×10-5 Mpa and a MAPE of 0.228%. It significantly outperforms the Caputo fractional derivative model by demonstrating a substantial enhancement with a 37% decrease in RMSE and a 36% reduction in MAPE. Further analysis of individual tomato fruit reveals the LSTM model's performance, with the minimum RMSE recorded at the septum position being 3.438×10-5 Mpa, 31% higher than the maximum RMSE at the locule position. Similarly, the lowest MAPE at the septum stands at 0.375%, outperforming the highest MAPE at the locule position by a significant margin of 90%. Moreover, the LSTM model consistently reports the smallest discrepancies between the predicted and observed values compared to classical stress relaxation models. This accuracy suggests that the LSTM model could effectively supplant classical stress relaxation models for predicting stress relaxation changes in individual tomato fruit.

Fast identification of tomatoes in natural environments by improved YOLOv5s

Real time recognition and detection of tomato fruit maturity is a key function of tomato picking robots. Existing recognition and detection algorithms have slow speed and low recognition accuracy for small tomatoes. Here, a tomato fruit maturity detection model YOLOv5s3 based on improved YOLOv5s was proposed and its accuracy was verified through comparative experiments. On the basis of YOLOv5s, an SC module was proposed based on channel shuffle packet convolution. Then, A C3S module is constructed, which replaced the original C3 module with this C3S module to reduce the number of parameters while maintaining the feature expression ability of the original network. And a 3-feature fusion FF module was put forward, which accepted inputs from three feature layers. The FF module fused two feature maps from the backbone network. The C2 layer of the backbone was integrated, and the large target detection head was removed to use dual head detection to enhance the detection ability of small targets. The experimental results showed that the improved model has a detection accuracy of 94.8%, a recall rate of 96%, a parameter quantity of 3.02M, and an average accuracy (mAP0.5) of 93.3% for an intersection over union (IoU) of 0.5. The detection speed reaches 9.4ms. It can quickly and accurately identify the maturity of tomato fruits, and the detection speed is 22.95%, 33.33%, 48.91%, 68.35%, 15%, and 25.98% higher than the original YOLOv5s, YOLOv5m, YOLOv5l, YOLOv5x, YOLOv5n, and YOLOv4, respectively. The real-time testing visualization results of different models indicated that the improved model can effectively improve detection speed and solve the problem of low recognition rate for small tomatoes, which can provide reference for the development of picking robots.

Overexpression of Sly-miR172a improved quality of tomato fruit by regulating MADS-box family

Fruit development is the key link in the reproductive cycle of plants, which determines the quality, yield and economic value of fruit. The present study investigated the effect of Sly-miR172a on the quality of the tomato fruit. The research results showed that overexpression of Sly-miR172a (OE-miR172a) in tomato fruit efficaciously increased the transverse and longitudinal diameter, weight, pericarp thickness, cell number and cell area. Compared with the wild-type (WT) fruit and the silencing miR172a by short tandem target mimic (STTM-miR172a), the relative expression levels of the MADS-box and the flavonoid biosynthesis synthesis pathway genes were higher in OE-miR172a. The expression level of AP2 and Cytokinin oxidase/dehydrogenase (CKX) family genes in OE-miR172a fruit was decreased, and accumulated more content of soluble sugars, lycopene, carotenoid, total phenol, anthocyanin and total flavonoid. The present study showed that overexpression of Sly-miR172 promoted the development and improved quality of tomato fruit.

Domestication and Genetic Improvement Alter the Symbiotic Microbiome Structure and Function of Tomato Leaf and Fruit Pericarp.

Many studies have attempted to explore the changes in the structure and function of symbiotic microbiomes, as well as the underlying genetic mechanism during crop domestication. However, most of these studies have focused on crop root microbiomes, while those on leaf and fruit are rare. In this study, we generated a comprehensive dataset including the metagenomic (leaf) and metatranscriptomic (fruit pericarp in the orange stage) data of hundreds of germplasms from three tomato clades: Solanum pimpinellifolium (PIM), cherry tomato (S. lycopersicum var. cerasiforme) (CER), and S. lycopersicum group (BIG). We investigated the effect of domestication and improvement processes on the structure of the symbiotic microbiome of tomato leaf and fruit pericarp, as well as its genetic basis. We were able to obtain the composition of the symbiotic microbiome of tomato leaf and fruit pericarp, based on which the tomato clade (PIM, CER, or BIG) was predicted with high accuracy through machine learning methods. In the processes of tomato domestication and improvement, changes were observed in the relative abundance of specific bacterial taxa, Bacillus for example, in the tomato leaf and fruit pericarp symbiotic microbiomes, as well as in the function of these symbiotic microbiomes. In addition, SNP loci that were significantly associated with microbial species that are characteristic of tomato leaf were identified. Our results show that domestication and genetic improvement processes alter the symbiotic microbiome structure and function of tomato leaf and fruit pericarp. We propose that leaf and fruit microbiomes are more suitable for revealing changes in symbiotic microbiomes during the domestication process and the underlying genetic basis for these changes due to the exclusion of the influence of environmental factors such as soil types on the microbiome structure.