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Ripening is an irreversible phenomenon involving several physiological, biochemical and organoleptic changes that affect the nutritional value, colour, texture and taste of fruit. Amongst the physical non-destructive technologies, Delayed Luminescence (DL) has been reported able to provide valid information on the functional status of living biological systems, reflecting changes in quality parameters following the occurrence of certain metabolic processes. In this study, we followed up and analysed the variations in the colour and DL signals emitted by tomato fruit as a function of their ripening degree. Four lots of tomato fruit, similar to each other for cultivar and geographical origin, were considered. Tomatoes were harvested at various maturity stages and stored in the dark at room temperature. The changes in DL emission trends were monitored at different times after harvesting for a period of about 20 days and correlated with the a*/b* colour ratio, which is normally used as an indicator of fruit ripeness degree. Results highlighted that the emission intensities, as well as the parameters by fitting DL decay curves, were strongly dependent on harvest maturity, varying significantly even as fruit ripeness progressed after their harvesting. Significant differences were also found between DL signals emitted by field-ripened tomatoes at the beginning of storage and those emitted by postharvest-ripened tomatoes at the end of the storage period. Delayed Luminescence may be used as a fast, reliable and sensitive tool for evaluating, more generally, the sensorial quality of fruit during postharvest storage. [ABSTRACT FROM AUTHOR]

Iron (Fe) and iodine (I) are essential microelements required for a healthy life, with Fe playing a vibrant role in oxygen transport, and I is vital for cognitive development and thyroid function. Global Fe and I deficiencies affect a significant portion of the population worldwide, leading to widespread health concerns, especially anemia, impaired cognitive function, and thyroid disorders. This review not only inspects the potential of agronomic biofortification to enrich Fe and I content in tomatoes, but also highlights its bright future for crop nutrition. It discusses the latest developments in agronomic biofortification methods focused on improving the enrichment of Fe and I in tomatoes, emphasizing practical approaches such as seed priming, soil application, and foliar spray. Notably, the review explores the promising impacts of Fe and I biofortification on growth, yield, and improved fruit quality in tomatoes. Moreover, it offers an in-depth investigation of the efficacy of agronomic biofortification in enhancing the nutritional contents of tomatoes by combining the most recent research findings. It highlights the impact of agronomic biofortification in mitigating micronutrient deficiencies worldwide and its capacity to encourage sustainable agriculture and improve community health by enhancing crop nutrition. [ABSTRACT FROM AUTHOR]

Tomato fruit ripening is an elaborate genetic trait correlating with significant changes at physiological and biochemical levels. Sugar metabolism plays an important role in this highly orchestrated process and ultimately determines the quality and nutritional value of fruit. However, the mode of molecular regulation is not well understood. Galactinoal-sucrose galactosyltransferase (GSGT), a key enzyme in the biosynthesis of raffinose family oligosaccharides (RFOs), can transfer the galactose unit from 1-α-D-galactosyl-myo-inositol to sucrose and yield raffinose, or catalyze the reverse reaction. In the present study, the expression of SlGSGT2 was decreased by Potato Virus X (PVX)-mediated gene silencing, which led to an unripe phenotype in tomato fruit. The physiological and biochemical changes induced by SlGSGT2 silencing suggested that the process of fruit ripening was delayed as well. SlGSGT2 silencing also led to significant changes in gene expression levels associated with ethylene production, pigment accumulation, and ripening-associated transcription factors (TFs). In addition, the interaction between SlGSGT2 and SlSPL-CNR indicated a possible regulatory mechanism via ripening-related TFs. These findings would contribute to illustrating the biological functions of GSGT2 in tomato fruit ripening and quality forming. [ABSTRACT FROM AUTHOR]

The application of organic fertilizers is one of the most important agricultural measures aimed at improving the flavor and productivity of Lycopersicon esculentum, with the granulation and coating of organic fertilizers, which can reduce seepage losses of great significance to the ecosystem. In this study, Jingcai 8 tomato was selected as the test material. Headspace solid-phase microextraction and gas chromatography–mass spectrometry (HS-SPME-GC-MS) methods were used to investigate the effects of different pelletized organic fertilizers and various coating materials on the flavor profile of the tomatoes. The results indicated that 67 volatile organic compounds (VOCs) were identified in the tomato fruits and 62 volatile compounds were identified in the leaves under different fertilizer treatments. The volatile compound content of the fruits in the BP treatment group was 35.38 μg/g, which was higher than that in other treatment groups, and the volatile compound content of the leaves was lower. A differential compound analysis with log2|fold change| ≥ 1 and variable important in projection (VIP) > 1 highlighted styrene, 3-methyl-1-butanol, and (E, E)-2,4-hexadienal as the major up-regulated compounds and methyl salicylate as the major down-regulated compound in the tomato fruit BCK (control) vs. BP. Moreover, the α-phellandrene content decreased in the tomato leaves. In addition, an analysis of the tomato fruit differential compounds and compounds with odor activity values (OAV) of ≥ 1, considering the OAV values of characteristic aroma compounds, identified key compounds affecting the flavor of the tomato fruits under the BP treatment. These included 2-nonenal, (E)-2-pentylfuran, trans-β-ionone, 1-penten-3-one, (E, E)-2,4-hexadienal, and 3-hexenol (fruity, floral, and herbaceous odors), (E, E)-2,4-heptadienal (fatty odor), and hexanal (green odor). The combined results analysis of the volatile compound content, differential compounds, and OAV values of characteristic aroma compounds aimed to clarify that the BP treatment group, which applied pelletized, large-grain organic fertilizer with polyurethane (pozzolanic + small-grain oil-coated + 2% paraffinic + 4% polyurethane) as a coating material, proved to be most effective in influencing the flavor of the tomato fruits. This finding lays the foundation for its potential commercial application in artificial orchards. [ABSTRACT FROM AUTHOR]

The aim of the study was to determine the effect of gaseous ozone, hydrogen peroxide and both factors used alternately on the profile of phenolic compounds of tomato fruits grown under cover. Phenolic compounds are natural substances, and their biosynthesis in plant tissues is affected by stress factors such as gaseous ozone and hydrogen peroxide. The experiment showed that the use of gaseous ozone at a dose of 2 ppm for 1.5 and 3 min significantly increased the total amount of phenolic compounds in tomato fruits compared to the control. In turn, in fruits obtained from plants to which hydrogen peroxide was applied at a concentration of 1 and 3% during vegetation, a lower amount of phenolic compounds was found compared to the control. In addition, the combined use of ozone and hydrogen peroxide in the case of four variants—2 ppm for 1.5 min + 1% H2O2; 2 ppm for 3 min + 1% H2O2; 2 ppm 1 min + 3% H2O2; 2 ppm 3 min + 3% H2O2—significantly increased the amount of phenolic compounds compared to the control.

Iron (Fe) and iodine (I) are essential microelements required for a healthy life, with Fe playing a vibrant role in oxygen transport, and I is vital for cognitive development and thyroid function. Global Fe and I deficiencies affect a significant portion of the population worldwide, leading to widespread health concerns, especially anemia, impaired cognitive function, and thyroid disorders. This review not only inspects the potential of agronomic biofortification to enrich Fe and I content in tomatoes, but also highlights its bright future for crop nutrition. It discusses the latest developments in agronomic biofortification methods focused on improving the enrichment of Fe and I in tomatoes, emphasizing practical approaches such as seed priming, soil application, and foliar spray. Notably, the review explores the promising impacts of Fe and I biofortification on growth, yield, and improved fruit quality in tomatoes. Moreover, it offers an in-depth investigation of the efficacy of agronomic biofortification in enhancing the nutritional contents of tomatoes by combining the most recent research findings. It highlights the impact of agronomic biofortification in mitigating micronutrient deficiencies worldwide and its capacity to encourage sustainable agriculture and improve community health by enhancing crop nutrition.

The aim of this research was to determine the impact of hydrogen peroxide spraying and ozone gas fumigation during the growing season of tomato plants grown under cover on the mechanical and chemical parameters of fruit harvested from these plants. Tomato plants were grown under cover in accordance with the principles of good agricultural practice in the soil and climatic conditions of southeastern Poland. During the growing season, tomato fruits were collected for testing in order to determine the impact of the applied variable factors on the modification of selected metabolic pathways of bioactive compounds. As part of the tests on the chemical properties of the fruits, the content of ascorbic acid, the total content of polyphenols, and the antioxidant potential were determined. Additionally, the influence of the tested variable factors on the mechanical properties of tomato fruits was determined. In the case of the total polyphenol content, the most beneficial effects were observed for fruits collected from plants treated with ozonation at a dose of 2 ppm for 3 min and spraying the plants with 1% hydrogen peroxide. The highest antioxidant potential was recorded for fruits of the variants ozonated with doses of 2 ppm for 1 min, 2 ppm for 1.5 min, and 2 ppm for 3 min compared to the remaining variants and controls. In turn, the vitamin C content increased significantly in the tested fruits after the ozonation of plants with a dose of 2 ppm for 1 min and ozonation with a dose of 2 ppm for 3 min combined with spraying plants with 3% hydrogen peroxide. In the case of the mechanical properties of tomato fruits, only the ozonation dose of 2 ppm for 3 min significantly improved them. [ABSTRACT FROM AUTHOR]

The plant cuticle is an important protective barrier on the plant surface, constructed mainly by polymerized cutin matrix and a complex wax mixture. Although the pathway of plant cuticle biosynthesis has been clarified, knowledge of the transcriptional regulation network underlying fruit cuticle formation remains limited. In the present work, we discovered that tomato fruits of the NAC transcription factor SlNOR-like1 knockout mutants (nor-like1) produced by CRISPR/Cas9 [clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9] displayed reduced cutin deposition and cuticle thickness, with a microcracking phenotype, while wax accumulation was promoted. Further research revealed that SlNOR-like1 promotes cutin deposition by binding to the promoters of glycerol-3-phosphate acyltransferase6 (SlGPAT6 ; a key gene for cutin monomer formation) and CUTIN DEFICIENT2 (SlCD2 ; a positive regulator of cutin production) to activate their expression. Meanwhile, SlNOR-like1 inhibits wax accumulation, acting as a transcriptional repressor by targeting wax biosynthesis, and transport-related genes 3-ketoacyl-CoA synthase1 (SlKCS1), ECERIFERUM 1-2 (SlCER1-2), SlWAX2 , and glycosylphosphatidylinositol-anchored lipid transfer protein 1-like (SlLTPG1-like). In conclusion, SlNOR-like1 executes a dual regulatory effect on tomato fruit cuticle development. Our results provide a new model for the transcriptional regulation of fruit cuticle formation. [ABSTRACT FROM AUTHOR]

Silicon can mitigate biotic and abiotic stresses in various plants; however, its effects on tomato quality under normal growth conditions are remain unclear. We used a randomized design with four Si treatments, CON (0 mmol/L), T1 (0.6 mmol/L), T2 (1.2 mmol/L), and T3 (1.8 mmol/L) on tomato fruit components Chlorogenic acid and rutin, among polyphenolic components, were increased by 56.99% and 20.31%, respectively, with T2 treatment compared to CON concentrations. T2 increased the sugar–acid ratio by 19.21%, compared to that with the CON treatment, and increased fruit Ca and Mg contents, compared to those with other treatments, improving the characteristic aroma. Furthermore, silicon application reduced the abscisic acid content by 112%, promoting ripening. Endogenous gibberellin, auxin, and salicylic acid, which retard fruit ripening and softening, were increased by 34.96%, 14.56%, and 35.21%, respectively. These findings have far-reaching implications for exogenous Si applications to enrich tomato nutritional and flavor qualities.

Tomato fruit ripening is an elaborate genetic trait correlating with significant changes at physiological and biochemical levels. Sugar metabolism plays an important role in this highly orchestrated process and ultimately determines the quality and nutritional value of fruit. However, the mode of molecular regulation is not well understood. Galactinoal-sucrose galactosyltransferase (GSGT), a key enzyme in the biosynthesis of raffinose family oligosaccharides (RFOs), can transfer the galactose unit from 1-α-D-galactosyl-myo-inositol to sucrose and yield raffinose, or catalyze the reverse reaction. In the present study, the expression of SlGSGT2 was decreased by Potato Virus X (PVX)-mediated gene silencing, which led to an unripe phenotype in tomato fruit. The physiological and biochemical changes induced by SlGSGT2 silencing suggested that the process of fruit ripening was delayed as well. SlGSGT2 silencing also led to significant changes in gene expression levels associated with ethylene production, pigment accumulation, and ripening-associated transcription factors (TFs). In addition, the interaction between SlGSGT2 and SlSPL-CNR indicated a possible regulatory mechanism via ripening-related TFs. These findings would contribute to illustrating the biological functions of GSGT2 in tomato fruit ripening and quality forming.

Postharvest losses of fruits and vegetables can occur due to cell breakdown and browning during controlled atmosphere storage as a result of low oxygen (O2) stress. Therefore, the study was designed to better understand the underlying mechanisms of the response of isolated tomato fruit cells incubated at low O2 (hypoxic and anoxic) conditions as a model system. The O2 stress conditions used for the experiment were based on the results of the Michaelis–Menten constant (Km) of respiration. A total of 56 polar metabolites belonging mainly to different functional groups, including amino acids, organic acids, sugars and sugar alcohols, were identified using GC-MS. O2 stress stimulated the biosynthesis of most of the free amino acids while decreasing the synthesis of most of the organic acids (especially those linked to the tricarboxylic acid cycle), sugars (except for ribose) and other nitrogen-containing compounds. The down-regulation of these TCA cycle metabolites served to provide energy to ensure the survival of the cell. Increases in the sugar alcohol levels and induction of fermentative metabolism were observed under low O2 stress. By employing multivariate statistics, metabolites were identified that were essential to the oxygen stress response and establishing the correlation between metabolite abundance, oxygen levels, and incubation period were achievable. A higher correlation was observed between the O2 levels and most of the metabolites.

BACKGROUND: To determine how abscisic acid (ABA) affects tomato fruit ripening at the protein level, mature green cherry tomato fruit were treated with ABA, nordihydroguaiaretic acid (NDGA) or sterile water (control, CK). The proteomes of treated fruit were analyzed and quantified using tandem mass tags (TMTs) at 7 days after treatment, and the gene transcription abundances of differently expressed proteins (DEPs) were validated with quantitative real‐time polymerase chain reaction. RESULTS: Postharvest tomato fruit underwent faster color transformation and ripening than the CK when treated with ABA. In total, 6310 proteins were identified among the CK and treatment groups, of which 5359 were quantified. Using a change threshold of 1.2 or 0.83 times, 1081 DEPs were identified. Among them, 127 were upregulated and 127 were downregulated in the ABA versus CK comparison group. According to KEGG and protein–protein interaction network analyses, the ABA‐regulated DEPs were primarily concentrated in the photosynthesis system and sugar metabolism pathways, and 102 DEPs associated with phytohormones biosynthesis and signal transduction, pigment synthesis and metabolism, cell wall metabolism, photosynthesis, redox reactions, allergens and defense responses were identified in the ABA versus CK and NDGA versus CK comparison groups. CONCLUSION: ABA affects tomato fruit ripening at the protein level to some extent. The results of this study provided comprehensive insights and data for further research on the regulatory mechanism of ABA in tomato fruit ripening. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The application of organic fertilizers is one of the most important agricultural measures aimed at improving the flavor and productivity of Lycopersicon esculentum, with the granulation and coating of organic fertilizers, which can reduce seepage losses of great significance to the ecosystem. In this study, Jingcai 8 tomato was selected as the test material. Headspace solid-phase microextraction and gas chromatography–mass spectrometry (HS-SPME-GC-MS) methods were used to investigate the effects of different pelletized organic fertilizers and various coating materials on the flavor profile of the tomatoes. The results indicated that 67 volatile organic compounds (VOCs) were identified in the tomato fruits and 62 volatile compounds were identified in the leaves under different fertilizer treatments. The volatile compound content of the fruits in the BP treatment group was 35.38 μg/g, which was higher than that in other treatment groups, and the volatile compound content of the leaves was lower. A differential compound analysis with log2|fold change| ≥ 1 and variable important in projection (VIP) > 1 highlighted styrene, 3-methyl-1-butanol, and (E, E)-2,4-hexadienal as the major up-regulated compounds and methyl salicylate as the major down-regulated compound in the tomato fruit BCK (control) vs. BP. Moreover, the α-phellandrene content decreased in the tomato leaves. In addition, an analysis of the tomato fruit differential compounds and compounds with odor activity values (OAV) of ≥ 1, considering the OAV values of characteristic aroma compounds, identified key compounds affecting the flavor of the tomato fruits under the BP treatment. These included 2-nonenal, (E)-2-pentylfuran, trans-β-ionone, 1-penten-3-one, (E, E)-2,4-hexadienal, and 3-hexenol (fruity, floral, and herbaceous odors), (E, E)-2,4-heptadienal (fatty odor), and hexanal (green odor). The combined results analysis of the volatile compound content, differential compounds, and OAV values of characteristic aroma compounds aimed to clarify that the BP treatment group, which applied pelletized, large-grain organic fertilizer with polyurethane (pozzolanic + small-grain oil-coated + 2% paraffinic + 4% polyurethane) as a coating material, proved to be most effective in influencing the flavor of the tomato fruits. This finding lays the foundation for its potential commercial application in artificial orchards.

The tomato is an economically important crop worldwide, although fungal infections by Alternaria alternata are the main cause of large postharvest fruit losses. One alternative to chemical control is the induction of the defense mechanism of plants with natural molecules such as chitin. Chitin is a polysaccharide of the fungal cell wall that is recognized by plasma membrane receptors that activates the transcription of plant defense genes. Because there is little information on the genes involved in chitin perception and defense responses to fungal chitin oligomers in tomato fruits, the main objective of this study was to identify pattern recognition receptor-associated genes in tomato fruits that perceive chitin oligomers from the necrotrophic fungus A. alternata using RNA-Seq. Chitin oligomers were obtained from A. alternata via enzymatic treatment. Tomato fruits in the pink ripening stage were exposed to these chitin oligomers for 30 min. The induction of tomato genes encoding a plasma membrane receptor that recognizes fungal chitin (LRR, RLK, SlLYK4, and SlCERK1) was observed 30 min after treatment. Similarly, the perception of Alternaria chitin oligomers triggered the induction of genes involved in signaling pathways regulated by ethylene and jasmonic acid. Further, activation of plant defense phenomena was confirmed by the upregulation of several genes encoding pathogenesis-related proteins. The scientific information generated in the present work will help to better elucidate tomato fruit's response to pathogens and to design protocols to reduce postharvest losses due to fungal infection. [ABSTRACT FROM AUTHOR]

Introduction: Lycopene consumption reduces risk and incidence of cancer and cardiovascular diseases. Tomatoes are a rich source of phytochemical compounds including lycopene as a major constituent. Lycopene estimation using high‐performance liquid chromatography is time‐consuming and expensive. Objective: To develop artificial intelligence models for prediction of lycopene in raw tomatoes using 14 different physicochemical parameters including salinity, total dissolved solids (TDS), electrical conductivity (EC), firmness, pH, total soluble solids (TSS), titratable acidity (TA), colour values on Hunter scale (L, a, b), total phenolic content (TPC), total flavonoid content (TFC) and antioxidant activity (AOA). Material and methods: The post‐harvest data acquisition was collected through investigation for more than 100 raw tomatoes stored for 15 days. Linear multivariate regression (LMVR), principal component regression (PCR) and partial least squares regression (PLSR) models were developed by splitting data set into train and test datasets. The training of models was performed using 10‐fold cross validation (CV). Results: Principal component analysis showed strong positive association between lycopene, colour value 'a', TPC, TFC and AOA. The R2 (CV), root mean square error (RMSE) (CV) and RMSE (Test) for best LMVR model was observed to be at 0.70, 8.48 and 9.69 respectively. The PCR model revealed R2 (CV) at 0.59, RMSE (CV) at 8.91 and RMSE (Test) at 10.17 while PLSR model revealed R2 (CV) at 0.60, RMSE (CV) at 9.10 and RMSE (Test) at 10.11. Conclusion: Results of the present study show that epidemiological studies suggest fully ripened tomatoes are most beneficial for consumption to ensure recommended daily intake of lycopene content. Tomatoes are a rich source of phytochemical compounds including lycopene as a major constituent. Lycopene estimation using high‐performance liquid chromatography is time‐consuming and dearer. This study aims to develop artificial intelligence models for prediction of lycopene in raw tomatoes using different physicochemical parameters. Linear multivariate regression, principal component regression and partial least squares regression models were developed. Results of present study read with epidemiological studies suggest fully ripened raw tomatoes be thermally processed for recommended daily intake of lycopene content. [ABSTRACT FROM AUTHOR]

Carotenoids constitute a large group of natural pigments widely distributed in nature. These compounds not only provide fruits and flowers with distinctive colors, but also have significant health benefits for humans. Lutein and zeaxanthin, both oxygen-containing carotenoids, are considered to play vital roles in promoting ocular development and maintaining eye health. However, humans and mammals cannot synthesize these carotenoid derivatives, which can only be taken from certain fruits or vegetables. Here, by introducing four endogenous synthetic genes, SlLCYE, SlLCYB, SlHYDB, and SlHYDE under fruit-specific promoters, we report the metabolic engineering of lutein/zeaxanthin biosynthesis in tomato fruit. Transgenic lines overexpression of one (SlLCYE), two (SlLCYE and SlLCYB; SlLCYB and SlHYDB), and all these four synthetic genes re-established the lutein/zeaxanthin biosynthetic pathways in the ripe tomato fruit and thus resulted in various types of carotenoid riched lines. Metabolic analyses of these engineered tomato fruits showed the strategy involved expression of SlLCYE tends to produce α-carotene and lutein, as well as a higher content of β-carotene and zeaxanthin was detected in lines overexpressing SlLCYB. In addition, the different combinations of engineered tomatoes with riched carotenoids showed higher antioxidant capacity and were associated with a significantly extended shelf life during postharvest storage. This work provides a successful example of accurate metabolic engineering in tomato fruit, suggesting the potential utility for synthetic biology to improve agronomic traits in crops. These biofortified tomato fruits could be also exploited as new research subjects for studying the health benefits of carotenoid derivatives.

Water deficit (WD) irrigation techniques to improve water use efficiency have been rapidly developed. However, the effect of WD irrigation on tomato quality has not been sufficiently studied. Here, we investigated the effects of varying water irrigation levels [T1–T4: 80%, 65%, 55%, and 45% of maximum field moisture capacity (FMC)] and full irrigation (CK: 90% of maximum FMC) on tomato fruits from the mature-green to red-ripening stages, to compare the nutritional and flavour qualities of the resulting tomatoes. The proline, aspartic, malic, citric, and ascorbic acid contents increased, phenylalanine and glutamic acid contents decreased, and the total amino and organic acid contents increased by 18.91% and 26.12%, respectively, in T2-treated fruits. Furthermore, the T2-treated fruits exhibited higher K and P contents alongside improved characteristic aromas. These findings provide novel insights for further improvements in tomato quality while also developing water-saving irrigation techniques.

Tomato fruit is highly susceptible to infection by Botrytis cinerea (B. cinerea), a dominant pathogen, during storage. Recent studies have shown that autophagy is essential for plant defense against biotic and abiotic stresses. Autophagy-related gene 5 (ATG5) plays a key role in autophagosome completion and maturation, and is rapidly induced by B. cinerea, but the potential mechanisms of ATG5 in Solanum lycopersicum (SlATG5) in postharvest tomato fruit resistance to B. cinerea remain unclear. To elucidate the role of SlATG5 in tomato fruit resistant to B. cinerea, CRISPR/Cas9-mediated knockout of SlATG5 was used in this study. The results showed that slatg5 mutants were more vulnerable to B. cinerea and exhibited more severe disease symptoms and lower activities of disease-resistant enzymes, such as chitinase (CHI), β-1,3-glucanase (GLU), phenylalanine ammonia-lyase (PAL), and polyphenol oxidase (PPO), than the wild type (WT). Furthermore, the study observed that after inoculation with B. cinerea, the relative expression levels of genes related to salicylic acid (SA) signaling, such as SlPR1, SlEDS1, SlPAD4, and SlNPR1, were higher in slatg5 mutants than in WT. Conversely, the relative expression levels of jasmonic acid (JA) signaling-related genes SlLoxD and SlMYC2 were lower in slatg5 mutants than in WT. These findings suggested that SlATG5 positively regulated the resistance response of tomato fruit to B. cinerea by inhibiting the SA signaling pathway and activating the JA signaling pathway. [ABSTRACT FROM AUTHOR]

The diversity and quantity of organic acids and the sugar content affect the taste, storage, and processing quality in ripe tomato fruits. Therefore, understanding the genetic potential of different tomato (Lycopersicon Mill.) varieties for this and other traits is an important first step in the early-stage research to select varieties for various uses. In this study, four red cherry tomato (Lycopersicon esculentum Mill.) varieties belonging to subsp. cultum, subsp. spontaneum, and subsp. subspontaneum were evaluated for their genetic potential to produce titratable acids (TA), especially ascorbic acid (AA), total carbohydrates (TCH), and seed protein content (SPC) in ripe fruit when grown under temperate climate zone conditions and in alkaline soil. This information is of great importance for the breeding programmes as well as for the process of development of new improved cherry tomato varieties. The correlation between biochemical properties of fruit and some physico-chemical parameters such as ash (AS), dry matter (DM), moisture (M), and acidity (pH) as well as the differences between studied varieties for each trait were investigated using statistical analysis. The results showed that all the studied varieties are susceptible to grow in the alkaline soil with pH up to 7.9 with the acceptable fruit quality. Significant differences were observed in ascorbic acid, ash, DM, and moisture content among all studied varieties. No differences were observed for pH, titratable acids, total carbohydrates, and seed protein content. L. esculentum var. cerasiforme showed the best potential to be included in the breeding programmes for the alkaline soil management under agroecological conditions of the temperate climate zone. [ABSTRACT FROM AUTHOR]

Soilless culture is considered the mostpromising, intensive, and sustainable approach with various advantages for plant production in terms of saving water and nutrients. It can provide consumers with sufficient and high-quality food. However, the commonly used growing substrate for soilless cultivation, coconut fiber (CF), is usually imported and expensive or even unavailable. The objectives of this study were to investigate the impact of local organic farm resources substrates on tomato (Solanum lycopersicum L.) plant growth, water relations, photosynthesis, chlorophyll fluorescence, and phytochemical analysis of fruits in a hydroponics culture system. Two growth substrates were evaluated: date-palm waste composted with animal manure (7:3 w/w) (DPAM) and date-palm trunk compost (DPT). CF and local soil were utilized as positive and negative controls, respectively, in randomized blocks. The results revealed that DPAM substrate enhanced plant growth and physiology: shoot development, leaves tissues hydration, and photosynthetic parameters, as well as chlorophyll fluorescence. However, DPT and CF improved fruit quality: water, mineral, sugar, and protein content. The antioxidant activity of the fruit extract was the greater in DPAM, reaching 13.8 mg GAEg−1 DW. This value wasdecreased in soil by 40%. Photosynthesis activity was the most important in DPAM with 12 µmol CO2 m−2 s−1, and only 6.4 µmol CO2 m−2 s−1 in the soil condition. However, regarding the non-photochemical quenching, the dissipated light energy was greater in soil (0.096 ± 0.02) than in DPAM (0.025 ± 0.04). Date-palm waste-based substrates improved tomato vegetative growth and fruit quality as compared to soil-based culture. Date-palm waste-based substrates supplemented with manure appear to be promising and less expensive alternatives to the coconut fiber substrate extensively used in soilless crops in North Africa. [ABSTRACT FROM AUTHOR]

Chitosan oligosaccharide (COS), a degradation product of chitosan, is easily accessible, highly bioactive, non-toxic, and well-soluble in water. The effects of COS on the qualitative attributes of tomato fruits were investigated in the current study. COS was administered to tomato plants (Solanum lycopersicum cv. Ruixinghongniu) by foliar spray and root irrigation in alternate cycles at concentrations of 0.5 g·L−1 and 0.16 g·L−1, respectively. The experimental outcomes revealed that COS treatment promoted the coloring and softening of tomato fruits. Lycopene, vitamin C, fructose, and glucose levels increased by 49.0%, 25.4%, 30.2%, and 33.4%, respectively, in COS-treated ripe fruits compared to controls. The volatile metabolome showed that COS application also increased the release of ten volatiles correlated with consumer preference (1-penten-3-one, (E)-2-pentenal, (E)-3-hexen-1-ol, (E)-2-heptenal, 2-isobutylthiazole, phenylacetaldehyde, 2-phenylethanol, 6-methyl-5-hepten-2-one, 6-methyl-5-hepten-2-ol, and β-ionone), contributing to an improved tomato flavor. Moreover, increased transcript levels of genes participating in ethylene biosynthesis, perception, and response along with enhanced ethylene production were observed in COS-treated fruits, suggesting that COS may regulate tomato fruit quality via the ethylene pathway. Taken together, our results indicated that the pre-harvest application of COS could improve tomato fruit quality attributes. [ABSTRACT FROM AUTHOR]

• Constructed an improved RTDETR-CASA model. • Successful application of improved model in rapid detection of tomato fruits. • A rapid method for obtaining tomato fruit morphological traits has been developed. • A new method for object detection and localization of automatic harvesting robots has been proposed. Rapid detection of tomato fruits and accurate acquisition of phenotypic traits are of great significance for robotic automatic picking control, yield prediction, and variety breeding. Tomato fruits are often densely distributed in a complex canopy and obscured by branches and leaves, making it difficult to accurately detect tomato fruits and obtain phenotypic traits without damage. This paper proposes an automatic detection method for tomatoes based on an improved RTDETR model. Firstly, on the basis of the self-made calibration plate, the color image sensor is used to acquire the tomato image. Then, a CASA structure consisting of three modules: Multiscale Dilated Convolution (MDC), Focused Feature Downsampler (FFD) and Adaptive Feature Upsampler (AFU) was designed and embedded into the Neck structure of the RTDETR network to construct a tomato fruit detection method based on the improved RTDETR model. Finally, by integrating machine learning and graphics processing technology, a fruit color extraction method was established based on the CIELAB color space, a fruit diameter calculation method based on edge detection and Hough transform, and a fruit weight and circumference measurement method based on statistical regression models. The experimental results show that the m A P _ 0.5 of the tomato fruit detection model established in this paper reaches 0.86, which is 3% higher than the original model; The correlation coefficient between the calculated and measured values of the horizontal and vertical diameters of the fruit was 0.79, and the mean square error (MSE) of the weight and circumference of the fruit was 0.26 and 0.27, respectively. This achievement has realized an accurate, lossless, and fast method for tomato fruit detection and phenotype calculation, providing quantitative reference indicators for fruit detection, positioning, and control of tomato automatic picking robots, and can provide technical support and guarantee for crop yield prediction and variety breeding. [ABSTRACT FROM AUTHOR]

[Display omitted] • Exogenous RVT reduced gray mold, with 20 μM being the most effective. • Exogenous RVT improved SlPR1 , SlLoxd and SlMYC2 expression and IAA content. • Exogenous RVT reduced the expression of SlNPR1 and the levels of ABA and GA3. • The effect of RVT + SNP is better than that of single treatment with RVT or SNP. • The combination of L-NNA and RVT treatment reduced the positive effect of RVT. Resveratrol (RVT), a plant antitoxin, plays an important role in plant resistance against pathogens. While nitric oxide (NO) as an essential signaling factor in disease resistance enhancement is well documented, the potential molecular interplay RVT and NO in postharvest tomato fruit defense against Botrytis cinerea (B.cinerea) still needs exploration. In this study, exogenous RVT reduced gray mold caused by B.cinerea in tomato fruit, with 20 μM being the most effective. Tomato fruit were treated with 20 μM RVT enhanced resistance against B.cinerea , as indicated by reduced symptoms of disease and improved activity of disease resistance related enzymes (PAL, PPO and CHI). In addition, RVT treatment improved the expression of SlPR1, SlLoxd and SlMYC2 , and promoted the accumulation of plant hormone IAA and ABA, but reduced the expression of SlNPR1 and the level of GA3. More importantly, the combined treatment of NO donor (SNP) and RVT notably enhanced disease resistance compared to RVT or SNP single treatment. However, the combination of NO inhibitor (L-NNA) and RVT treatment even reduced the positive effect of RVT. Meanwhile, the expression of SlPR1 , SlLoxd and SlMYC2 and the accumulation of IAA and ABA in RVT + SNP treated fruit were higher than those in the RVT or SNP single treatment. Thus, our data demonstrate that RVT and NO synergistically enhance resistance against B. cinerea in tomato fruit by regulating phytohormones. [ABSTRACT FROM AUTHOR]

Tomatoes develop chilling injury after low-temperature storage, which is often indicated by ion leakage from the tissues caused by cell membrane damage. However, the chilling injury causes a decline in tomato quality, which was already serious due to ion leakage. This study assumed that other physiological reactions precede cell membrane damage in tomatoes exposed to chilling stress. This hypothesis was investigated by measuring several physical, chemical and physiological parameters of tomatoes. Using samples stored at 2 or 5°С without chilling injury-induced cell membrane damage, this study confirmed other abnormal physiological reactions, such as ethylene production, respiration, electrochemical resistance in extracellular fluids, gene expression of heat shock protein, succinic acid content, and others. The obtained information can help clarify the initial response of chilling injury and is useful to determine the distribution property of tomatoes for avoiding chilling injury-induced cell membrane damage. • Initial reactions of tomato fruit by chilling injury as a distribution property. • BIS, ethylene production, respiration, others indicated chilling injury occurrence. • The abnormal responses were confirmed although cell membrane was not damaged. • NMR signal assumed succinic acid might be affected by chilling injury. • Initial reactions of chilling injury might be not limited to cell membrane damage. [ABSTRACT FROM AUTHOR]

SlSPL-CNR is a multifunctional transcription factor gene that plays important roles in regulating tomato fruit ripening. However, the molecular basis of SlSPL-CNR in the regulatory networks is not exactly clear. In the present study, the biochemical characteristics and expression levels of genes involved in ethylene biosynthesis in Colorless nonripening (Cnr) natural mutant were determined. The proteomic changes during the ripening stage were also uncovered by isobaric tags for relative and absolute quantitation (iTRAQ)–based quantitative proteomic analysis. Results indicated that both the lycopene content and soluble solid content (SSC) in Cnr fruit were lower than those in wild-type AC fruit. Meanwhile, pH, flavonoid content, and chlorophyll content were higher in Cnr fruit. Expressions of genes involved in ethylene biosynthesis were also downregulated or delayed in Cnr fruit. Furthermore, 1024 and 1234 differentially expressed proteins (DEPs) were respectively identified for the breaker and 10 days postbreaker stages. Among them, a total of 512 proteins were differentially expressed at both stages. In addition, the functions of DEPs were classified by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. Results would lay the groundwork for wider explorations of the regulatory mechanism of SlSPL-CNR on tomato fruit ripening. [ABSTRACT FROM AUTHOR]

Melatonin plays key roles in improving fruit quality and yield by regulating various aspects of plant growth. However, the effects of how melatonin regulates primary and secondary metabolites during fruit growth and development are poorly understood. In this study, the surfaces of tomato fruit were sprayed with different concentrations of melatonin (0, 50, and 100 µmol·L−1) on the 20th day after anthesis; we used high-performance liquid chromatography (HPLC) and liquid chromatography/mass spectrometry (LC/MS) to determine the changes in primary and secondary metabolite contents during fruit development and measured the activity of sucrose metabolizing enzymes during fruit development. Our results showed that 100 µmol·L−1 melatonin significantly promoted the accumulation of soluble sugar in tomato fruit by increasing the activities of sucrose synthase (SS), sucrose phosphate synthase (SPS), and acid convertase (AI). The application of 100 µmol·L−1 melatonin also increased the contents of ten amino acids in tomato fruit as well as decreased the contents of organic acids. In addition, 100 µmol·L−1 melatonin application also increased the accumulation of some secondary metabolites, such as six phenolic acids, three flavonoids, and volatile substances (including alcohols, aldehydes, and ketones). In conclusion, melatonin application improves the internal nutritional and flavor quality of tomato fruit by regulating the accumulation of primary and secondary metabolites during tomato fruit ripening. In the future, we need to further understand the molecular mechanism of melatonin in tomato fruit to lay a solid foundation for quality improvement breeding. [ABSTRACT FROM AUTHOR]

Extensive data have demonstrated that carotenoid accumulation in tomato fruit is influenced by environmental cues and hormonal signals. However, there is insufficient information on the mechanism of its transcriptional regulation, as many molecular roles of carotenoid biosynthetic pathways remain unknown. In this work, we found that the silence of the BEL1-like family transcription factor (TF) BEL1-LIKE HOMEODOMAIN 11 (SlBEL11) enhanced carotenoid accumulation in virus induced gene silencing (VIGS) analysis. In its RNA interference (RNAi) transgenic lines, a significant increase in the transcription level for the lycopene beta cyclase 2 (SlLCY-b2) gene was detected, which encoded a key enzyme located at the downstream branch of the carotenoid biosynthetic pathway. In Electrophoretic mobility shift assay (EMSA), SlBEL11 protein was confirmed to bind to the promoter of SlLCY-b2 gene. In addition, the dual-luciferase reporter assay showed its intrinsic transcriptional repression activity. Collectively, our findings added a new member to the carotenoid transcriptional regulatory network and expanded the functions of the SlBEL11 transcription factor.

The tomato is an economically important crop worldwide, although fungal infections by Alternaria alternata are the main cause of large postharvest fruit losses. One alternative to chemical control is the induction of the defense mechanism of plants with natural molecules such as chitin. Chitin is a polysaccharide of the fungal cell wall that is recognized by plasma membrane receptors that activates the transcription of plant defense genes. Because there is little information on the genes involved in chitin perception and defense responses to fungal chitin oligomers in tomato fruits, the main objective of this study was to identify pattern recognition receptor-associated genes in tomato fruits that perceive chitin oligomers from the necrotrophic fungus A. alternata using RNA-Seq. Chitin oligomers were obtained from A. alternata via enzymatic treatment. Tomato fruits in the pink ripening stage were exposed to these chitin oligomers for 30 min. The induction of tomato genes encoding a plasma membrane receptor that recognizes fungal chitin (LRR, RLK, SlLYK4, and SlCERK1) was observed 30 min after treatment. Similarly, the perception of Alternaria chitin oligomers triggered the induction of genes involved in signaling pathways regulated by ethylene and jasmonic acid. Further, activation of plant defense phenomena was confirmed by the upregulation of several genes encoding pathogenesis-related proteins. The scientific information generated in the present work will help to better elucidate tomato fruit’s response to pathogens and to design protocols to reduce postharvest losses due to fungal infection.

SUMMARY: Ripening is the last, irreversible developmental stage during which fruit become palatable, thus promoting seed dispersal by frugivory. In Alisa Craig fruit, mRNAs with increasing m5C levels, such as STPK and WRKY 40, were identified as being involved in response to biotic and abiotic stresses. Furthermore, two mRNAs involved in cell wall metabolism, PG and EXP‐B1, also presented increased m5C levels. In the Nr mutant, several m5C‐modified mRNAs involved in fruit ripening, including those encoding WRKY and MADS‐box proteins, were found. Targets of long non‐coding RNAs and circular RNAs with different m5C sites were also found; these targets included 2‐alkenal reductase, soluble starch synthase 1, WRKY, MADS‐box, and F‐box/ketch‐repeat protein SKIP11. A combined analysis of changes in 5mC methylation and mRNA revealed many differentially expressed genes with differentially methylated regions encoding transcription factors and key enzymes related to ethylene biosynthesis and signal transduction; these included ERF084, EIN3, AP2/ERF, ACO5, ACS7, EIN3/4, EBF1, MADS‐box, AP2/ERF, and ETR1. Taken together, our findings contribute to the global understanding of the mechanisms underlying fruit ripening, thereby providing new information for both fruit and post‐harvest behavior. Significance Statement: This is the first study on the regulation of RNA (m5C) methylation and non‐coding RNA (m5C) methylation on tomato fruit ripening in the world, which will establish a great foundation for tomato breeding and fresh fruit ripening regulation research. [ABSTRACT FROM AUTHOR]

The morphological and anatomical study of the seed formation features in a juicy tomato fruit was carried out. The ovules, which form on the placenta, have been shown to be gradually enveloped by the protrusions of placental tissue that arises simultaneously with them. As a result of this process, each seed is enclosed in an individual capsule. These seed capsules have been shown in vivo to be airtight and air-filled. Tomato seeds, as has been shown in this study, develop inside these capsules until the full maturity of the fruit and do not come into contact with the detached and moldered cells of the placenta protrusions, which convert into a gel (pulp). Using scanning electron microscopy, it was possible to reveal the details of a ribbon-like "pubescence" formation of the tomato seed, as well as to understand the mechanism of cracking of the outer layer cells in the seed coat, associated with the detection of calcium oxalate crystals in these cells. The unique outer layer of the tomato seed coat seems to play the role of a scaffold that maintains a constant volume of the protective capsule. [ABSTRACT FROM AUTHOR]

Key message: In SlHDC-A promoter, SlHDC-A core-ES is an essential region for fruit-specific expression and interacts with GATA, HSF and AP1. Triplication of essential region was proposed as a minimal fruit-specific promoter. In plant biotechnology, fruit-specific promoter is an important tool for the improvement and utilization of tomato fruit. To expand our understanding on fruit-specific expression, it is necessary to determine the promoter region involved in fruit-specific transcriptional activity and transcriptional regulations of the promoter. In previous study, we isolated a fruit-specific SlHDC-A core promoter specifically expressed during tomato ripening stages. In this study, we identified SlHDC-A promoter region (SlHDC-A core-ES) that is essential for fruit-specific expression of the SlHDC-A. To understand the molecular mechanisms of fruit-specific expression of the SlHDC-A promoter, we first identified the putative transcription factor binding elements in the SlHDC-A core promoter region and corresponding putative transcription factors which are highly expressed during fruit maturation. Yeast one hybrid analysis confirmed that GATA, HSF, and AP1 interact with the SlHDC-A core-ES promoter region. Further transactivation analysis revealed that expression of the three transcription factors significantly activated expression of a reporter gene driven by SlHDC-A core-ES promoter. These results suggest that GATA, HSF, and AP1 are involved in the fruit-specific expression of SlHDC-A promoter. Furthermore, the synthetic promoter composed of three tandem repeats of SlHDC-A core-ES showed relatively higher activity than the constitutive 35S promoter in the transgenic tomato fruits at the orange stage. Taken together, we propose a new synthetic promoter that is specifically expressed during fruit ripening stage. [ABSTRACT FROM AUTHOR]

Recently, increasing attention has been focused on prediction models for quality changes of fresh produce based on mass-loss values. In this study, we applied a virtual distribution treatment (a 2-day transportation period followed by a 7-day storage period) of tomato fruit, and the effects of transportation temperature (0, 5, 10, and 20 °C) on fruit mass loss and color (a* values) of stored green, pink, and red tomatoes at 10 °C were investigated. In addition, the relationship between fruit mass loss and a* values during the virtual transportation treatment were analyzed. The virtual transportation at 0–5℃ was effective in inhibiting mass loss in green and pink tomatoes. Further, an excess increase in mass loss due to chilling injury was confirmed in red tomatoes at 0 °C; however, this phenomenon did not occur at 5 °C. Presumably, tomato chilling injury is reversible for a temperature-dependent period. The a* values of the green and pink tomatoes increased gradually at high temperature. The changes in a* values and the extent of fruit mass loss were recorded for green and pink tomatoes, and linear regression analysis allowed the changes in a* value to be predicted from the mass loss data with a high degree of accuracy (R2 = 0.89–0.91). [ABSTRACT FROM AUTHOR]

Tomato fruit are sensitive to chilling injury (CI) during cold storage. Several factors have been discovered to be involved in chilling injury of tomato fruit. Plant hormones play an important regulatory role, however, the relationship between chilling injury and N6-methyladenosine (m6A) methylation of transcripts in plant hormone pathways has not been reported yet. In order to clarify the complex regulatory mechanism of m6A methylation on chilling injury in tomato fruit, Nanopore direct RNA sequencing was employed. A large number of enzymes and transcription factors were found to be involved in the regulation process of fruit chilling injury, which were associated with plant hormone, such as 1-aminocyclopropane 1-carboxylate synthase (ACS), aspartate aminotransferase (AST), auxin response factor (ARF2), ethylene response factor 2 (ERF2), gibberellin 20-oxidase-3 (GA20ox) and jasmonic acid (JA). By conjoint analysis of the differential expression transcripts related to chilling injury and m6A methylation differential expression transcripts 41 differential expression transcripts were identified involved in chilling injury including 1-aminocyclopropane-1-carboxylate oxidase (ACO) and pectinesterase (PE) were down-regulated and heat shock cognate 70 kD protein 2 (cpHSC70), HSP70-binding protein (HspBP) and salicylic acid-binding protein 2 (SABP2) were up-regulated. Our results will provide a deeper understanding for chilling injury regulatory mechanism and post-harvest cold storage of tomato fruit.

The present study examines the impacts of combined cold plasma treated water (PW) and osmodehydration (OD) pretreatment (PO), and operation parameters like PW duration and voltage of treatment on the dehydration, functional and sensory characteristics of sliced tomato fruits subjected to simultaneous infrared-assisted pulsed vacuum drying (IR-PVD). From the results, PO pretreatment modified the surface structures by the formation of microchannels and cavities through impingements from the reactive species (RS), and was improved due to increased treatment duration and voltage, and resulted in accelerating the transfer of moisture from the slices to the surroundings during the dehydration process. Consequently, PO pretreatment achieved an enhancement in the moisture diffusivity by up to 64.83%, shortened the total drying time by up to 40%, and presented substantial improvements in the physicochemical properties including vitamin C, lycopene, colour, total soluble solids, phenolic and flavonoid contents, and overall human acceptability. However, significant decreases in rehydration and hardness properties were shown compared with control, and higher rehydration by up to 21.66% at higher treatment duration and voltage when compared with OD pretreatment. Overall, PO pretreatment incited an effective moisture removal and retention of vital physicochemical and bioactive constituents in the slices due to the activities of plasma injected RS. This study provides an empirical basis for the application of PO during IR-PVD of fruits and vegetables and demonstrated as a suitable energy-saving alternative for improving the conventional OD of foods in the industry. • Tomato slices were dried by infrared-assisted pulsed vacuum drying (IR-PVD). • Cold plasma plus osmodehydration (PO) pretreatments was applied prior drying. • PO pretreatment accelerated moisture removal and shortened processing duration. • PO pretreatment improved physicochemical properties of pretreated samples. • PCA showed vivid segregations for plasmosmotic pretreated samples during IR-PVD. [ABSTRACT FROM AUTHOR]

Chemical pesticides have a plenty of negative impacts on human health and on the environment. Thus, modern agriculture cropping systems are moving towards more eco-friendly alternatives. This study aims to investigate the bioprotective effect of three volatile organic compounds (VOCs: N-Ethylaniline, 2-Heptanone and 3-Methylbutan-1-ol) produced by endophytic bacteria against 21 phytopathogenic fungal strains and their bioprotective effect on horticulture products i.e. tomato and lemon fruits and Potato tubers. The results showed that N-Ethylaniline and 3-methylbutan-1-ol had better antagonistic activity against the fungal strains by inhibiting the mycelia growth of the studied fungal strains at different concentrations. The N-Ethylaniline showed the lowest effective concentration (EC50) against B. cinerea strain S5 (0,258 mL/L headspace), Fusarium solani strain SB4.15.1 (0,496 mL/L headspace) and Colletotrichum gloeosporioides strain ManS3Fr02 (0,206 mL/L headspace). At EC50 this compound significantly reduced B. cinerea and C. gloeosporioides infections on tomato and lemon fruits, respectively. However, N-Ethylaniline didn’t showed significant effect on F. solani infection on Potato tubers. This study showed the broad spectrum of in vitro antifungal activity of N-Ethylaniline and its effect to reduce postharvest infections of some fungal diseases suggesting its potential use as a biofumigant.

Tomato fruit is highly susceptible to infection by Botrytis cinerea (B. cinerea), a dominant pathogen, during storage. Recent studies have shown that autophagy is essential for plant defense against biotic and abiotic stresses. Autophagy-related gene 5 (ATG5) plays a key role in autophagosome completion and maturation, and is rapidly induced by B. cinerea, but the potential mechanisms of ATG5 in Solanum lycopersicum (SlATG5) in postharvest tomato fruit resistance to B. cinerea remain unclear. To elucidate the role of SlATG5 in tomato fruit resistant to B. cinerea, CRISPR/Cas9-mediated knockout of SlATG5 was used in this study. The results showed that slatg5 mutants were more vulnerable to B. cinerea and exhibited more severe disease symptoms and lower activities of disease-resistant enzymes, such as chitinase (CHI), β-1,3-glucanase (GLU), phenylalanine ammonia-lyase (PAL), and polyphenol oxidase (PPO), than the wild type (WT). Furthermore, the study observed that after inoculation with B. cinerea, the relative expression levels of genes related to salicylic acid (SA) signaling, such as SlPR1, SlEDS1, SlPAD4, and SlNPR1, were higher in slatg5 mutants than in WT. Conversely, the relative expression levels of jasmonic acid (JA) signaling-related genes SlLoxD and SlMYC2 were lower in slatg5 mutants than in WT. These findings suggested that SlATG5 positively regulated the resistance response of tomato fruit to B. cinerea by inhibiting the SA signaling pathway and activating the JA signaling pathway.

Ripe fruit, rich in essential nutrients, holds significant economic value. In this study, we investigate the dynamics of amino acids during the shelf-life of tomato fruit. To examine their influence on fruit ripening, we treat tomato fruit with either L-arginine (Arg) or L-cysteine (Cys). Our findings demonstrate that application of Arg or Cys retards fruit color change from green to red, and hinders the alterations in titratable acidity and soluble sugar content. Furthermore, Arg or Cys treatment suppresses the activities of key enzymes involved in ethylene biosynthesis, namely 1-aminocyclopropane-1-carboxylic acid (ACC) synthase (ACS) and ACC oxidase (ACO), by downregulating the expression of SlACS2/4 and SlACO1. This suppression further inhibits ripening-associated ethylene production. Overall, our study unveils that Arg and Cys treatments delay the ripening process of tomato fruit. The modulation of amino acid profile emerges as a significant factor in regulating fruit ripening and maintaining fruit quality during shelf-life. [Display omitted] • The amino acids profile is different in tomato fruit at distinct maturity stages. • Exogenous arginine or cysteine affects the color parameters of tomato fruit. • Arginine or cysteine influences the soluble sugar level and acidity of tomato fruit. • Arginine or cysteine treatment suppresses the ripening-induced ethylene production. [ABSTRACT FROM AUTHOR]

Edible coatings can provide an alternative for extending the postharvest shelf life of fresh fruits and vegetables. The effect of two edible coatings and their combinations were studied on some physical qualities of tomato fruits. Gum arabic was formulated from the exudate of Acacia tree, and beeswax was sourced from the Horticulture Department, University for Development Studies. Cassava starch was used as a plasticizer for both materials. Tomato fruits were treated with gum arabic, beeswax, and a combination of the two at concentrations 5, 10, and 15%. Treated and untreated fruits were examined for their weight loss and decay during 20 days of storage and sampling were done at 4 days intervals. Fruits coated with gum arabic alone did not show much positive impact on weight loss and decay when compared to the control fruits. The beeswax alone however showed a positive impact on weight loss and decay. Furthermore, the combination of the beeswax and gum arabic resulted in the highest performance with reduced weight loss of 26.7%, and 13.9% decay after 20 days in storage. Hence, the combination of gum arabic and beeswax could extend the postharvest shelf life of tomato fruits at 29°C and 72 - 75% temperature and relative humidity, respectively. [ABSTRACT FROM AUTHOR]

Many fruits are harvested at the early ripening stage and left to attain an edible stage during the post-ripening process or by ethylene treatment. However, the post-ripening quality of fruit is generally inferior to the quality of fruit that ripened naturally. Sugar metabolism plays critical roles in regulating fruit flavor and stress responses. Methyl Jasmonate (MeJA) treatment modulates sugar accumulations and postharvest fruit quality. However, the regulation mechanism of MeJA on sugar metabolism and its relationship with fruit post-ripening quality are unclear. The results indicated that MeJA-treated fruit possessed higher total antioxidant, lycopene and soluble solids content and lower electrical conductivity and malondialdehyde content. Besides, the post-ripening quality of fruit was strongly related to the starch and sucrose content. Compared to the control and ethephon treatments, MeJA treatment increased the activities and transcript levels of amylase, sucrose phosphate synthase (SPS) and sucrose synthase (SUS), but decreased the activities and transcript levels of acid invertase and neutral invertase. Further analysis suggested that the sucrose content had a strongly positive correlation with the activities and transcript levels of SUS and SPS, except SlSPS2. Thus, MeJA treatment improved fruit post-ripening quality by regulating sugar metabolism. [ABSTRACT FROM AUTHOR]

The demand for daily consumption of tomato fruit is increasing immensely. Nevertheless, the fruit is exposed to mechanical damage, shrinking, and softening as the maturity stages, handling, and storage are inappropriate, thereby affecting the texture. The study aimed to assess the texture profile, pectinase activity, and physicochemical parameters in tomato fruit at different maturity stages and storage temperatures. The fruits were harvested at 1-4 weeks after pollination and stored at a temperature of 16 ºC and 25ºC. There was an increase in the redness color (a*), TSS content, weight loss, respiration rate, and ethylene production, while the hardness, lightness color (L*), pH, and TA decreased with an increase in maturity stages at different storage temperatures. The higher Polygalacturonase (PG) and Pectin methylesterase (PME) enzyme activities were observed at 25 ºC compared to storage temperature of 16 ºC. It was confirmed that pectinase activity extremely affected the texture profile. For commercial purposes, it is suggested that tomatoes are harvested at 2nd and 3rd week after pollination for long distance transportation and at 4th week for fresh consumption and stored at a temperature of 16 °C.

In this study, the role of Sly-miR171e on post-harvest cold tolerance of tomato fruit was researched. The results showed that overexpression of Sly-miR171e (miR171e-OE) promoted postharvest chilling injury (CI) of tomato fruit at the mature red (MR) and mature green (MG) stage. Contrasted with the wild type (WT) and miR171e-OE fruit, the knockdown of Sly-miR171e (miR171e-STTM) showed a lower CI index, lower hydrogen peroxide (H2O2) content, and higher fruit firmness after harvest. In the fruit of miR171e-STTM, the expression level of GRAS24, CBF1, GA2ox1, and COR, and the GA3 content were ascended, while the expression levels of GA20ox1 and GA3ox1 were descended. The research demonstrated that CI in tomato fruit was alleviated at low temperature storage by silencing Sly-miR171e with short tandem target mimic (STTM) technology. Furthermore, it also provided helpful information for genetic modification of miR171e and control of CI in the postharvest fruit.

This study explored the effect of different locally produced edible coating material, bee wax (BW), shea butter (SB) and cassava starch (CS) coatings on the physical and chemical properties of tomato fruits stored at 20 °C and relative humidity of 80 – 90% for 20 days. The physiochemical properties and quality retention of coated tomato fruits were assessed for antioxidant properties (ABTS and DPPH), total phenolic content (TPC), enzyme activity (PPO), organoleptic properties, weight loss, firmness, and shelf-life of the fruits. Tomato fruits treated with Bee wax (BW) preserve the antioxidant activity, total phenolic content (TPC), organoleptic properties and resisted enzymes activities compared to the SB and CS. The results also suggest that bee wax (BW) treatment delayed ripening, weight loss, firmness, and extended the storage life of fruits compared to the SB and CS. Taking into consideration of the above physical and chemical properties, BW treatment will be a good postharvest technology for retaining the quality and extending the shelf life of fresh tomato fruits. The current findings will make available more information for selecting edible coatings for tomato storage.

Tomato fruit phenotypes are important agronomic traits in tomato breeding as a reference index. The traditional measurement methods based on manual observation, however, limit the high-throughput data collection of tomato fruit morphologies. In this study, fruits of 10 different tomato cultivars with considerable differences in fruit color, size, and other morphological characters were selected as samples. Constant illumination condition was applied to take images of the selected tomato fruit samples. Based on image recognition, automated methods for measuring color and size indicators of tomato fruit phenotypes were proposed. A deep learning model based on Mask Region-Convolutional Neural Network (R-CNN) was trained and tested to analyze the internal structure indicators of tomato fruit. The results revealed that the combined use of these methods can extract various important fruit phenotypes of tomato, including fruit color, horizontal and vertical diameters, top and navel angles, locule number, and pericarp thickness, automatically. Considering several corrections of missing and wrong segmentation cases in practice, the average precision of the deep learning model is more than 0.95 in practice. This suggests a promising locule segmentation and counting performance. Vertical/horizontal ratio (fruit shape index) and locule area proportion were also calculated based on the data collected here. The measurement precision was comparable to manual operation, and the measurement efficiency was highly improved. The results of this study will provide a new option for more accurate and efficient tomato fruit phenotyping, which can effectively avoid artificial error and increase the support efficiency of relevant data in the future breeding work of tomato and other fruit crops. [ABSTRACT FROM AUTHOR]

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