Tomato Fruit Production Research Articles

Deciphering the Effects of Different Calcium Sources on the Plant Growth, Yield, Quality, and Postharvest Quality Parameters of ‘Tomato’

Tomatoes are one of the most important vegetables in every home, especially in South Asian countries, used as a vegetable, ketchup, and condiment in many kitchen recipes. It is a good source of calcium, potassium, folate, vitamin A, vitamin K, and lycopene, which are beneficial for the human body and protect it against different diseases. Nutrient management is a key factor for the best quality production of tomato fruit. The present study was conducted to compare the efficiency of different calcium salts (calcium sulphate, calcium carbonate, calcium nitrate, and calcium chloride) in improving the growth, yield, and other quality-related parameters of tomatoes. A single field experiment was conducted and laid out according to the Randomized Complete Block Design (RCBD) with a single factor in the field and a Complete Randomized Design (CRD)) for postharvest fruit storage. The results obtained from this experiment suggest that plants treated with 2% calcium chloride solution exhibited the greatest plant height (85.27 cm), number of leaves (221), yield per plant (2.3 kg), ascorbate peroxidase (290.75 m mol s−1 kg−1), superoxide dismutase (7.13 m mol s−1 kg−1), catalase (18.74 m mol s−1 kg−1), total phenolics (2.44 mg g−1), and β carotene (0.48 µg g−1). During postharvest storage, the maximum shelf life (18 days), minimum disease incidence (4.78%), weight loss (6.61%), and ethylene production (119.6 µL C2H4 kg−1h−1) rate were also observed in calcium-treated fruits.

Intra-canopy LED lighting outperformed top LED lighting in improving tomato yield and expression of the genes responsible for lycopene, phytoene and vitamin C synthesis

Greenhouses located at high latitudes and in cloudy areas often experience a low quality and quantity of light, especially during autumn and winter. This low daily light integral (DLI) reduces production rate, quality, and nutritional value of many crops. This study was conducted on Sakhiya RZ F1 tomato plants to evaluate the impact of LED lights on the growth and nutritional value of tomatoes in a greenhouse with low daily light due to cloudy weather. The treatments included LED growth lights in three modes: top lighting, intra-canopy lighting, and combined top and intra-canopy lighting. The results showed that although the combined top and intra-canopy lighting reached the maximum increase in tomato yield, exposure to intra-canopy LED lighting alone outperformed in tomato fruit yield increase (28.46%) than exposure to top LED lighting alone (12.12%) when compared to no supplemental lighting during the entire production year. Intra-canopy exposure demonstrated the highest increase in tomato lycopene (31.3%), while top and intra-canopy lighting exhibited the highest increase in vitamin C content (123.4%) compared to the control. The LED light treatment also had a very positive effect on the expression of genes responsible for metabolic cycles, including Psy1, LCY-β, and VTC2 genes, which had collinearity with the increase in tomato fruit production.

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).

Molecular Methods for the Simultaneous Detection of Tomato Fruit Blotch Virus and Identification of Tomato Russet Mite, a New Potential Virus–Vector System Threatening Solanaceous Crops Worldwide

Tomato fruit blotch virus (ToFBV) (Blunervirus solani, family Kitaviridae) was firstly identified in Italy in 2018 in tomato plants that showed the uneven, blotchy ripening and dimpling of fruits. Subsequent High-Throughput Sequencing (HTS) analysis allowed ToFBV to be identified in samples collected in Australia, Brazil, and several European countries, and its presence in tomato crops was dated back to 2012. In 2023, the virus was found to be associated with two outbreaks in Italy and Belgium, and it was included in the EPPO Alert list as a potential new threat for tomato fruit production. Many epidemiologic features of ToFBV need to be still clarified, including transmission. Aculops lycopersici Massee (Acariformes: Eriophyoidea), the tomato russet mite (TRM), is a likely candidate vector, since high population densities were found in most of the ToFBV-infected tomato cultivations worldwide. Real-time RT-PCR tests for ToFBV detection and TRM identification were developed, also as a duplex assay. The optimized tests were then transferred to an RT-ddPCR assay and validated according to the EPPO Standard PM 7/98 (5). Such sensitive, reliable, and validated tests provide an important diagnostic tool in view of the probable threat posed by this virus–vector system to solanaceous crops worldwide and can contribute to epidemiological studies by simplifying the efficiency of research. To our knowledge, these are the first molecular methods developed for the simultaneous detection and identification of ToFBV and TRM.

Effects of the Agrivoltaic System on Crop Production: The Case of Tomato (Solanum lycopersicum L.)

Climate change, with rising temperatures, water crises, and an increased frequency of climate disturbances, poses a threat to the ability of agroecosystems to ensure human access to food by affecting both the quantity and quality of crop production. Currently, there is growing knowledge about the fact that agrivoltaic systems may represent a direct strategy to cope with climate change driven by carbon dioxide emissions for energy production, preserving the capacity of agroecosystems to maintain food security. The aim of this work was to investigate the impact of environmental conditions generated by photovoltaic (PV) panels for sustaining open-field tomato (Solanum lycopersicum L.) fruit production under varying water supply regimes. Tomato plants were grown beneath PV panels or in full sunlight. In each scenario, two plots with an equal number of plants were subjected to different irrigation levels: high watering (HW) and low watering (LW). The results showed a lower number of tomato fruit produced grown under the PV panels, with an increased fruit size and water content under a normal water supply. The Brix degrees of the tomato fruits grown under the panel were more comparable to the fruits commercially available on the market than the Brix degree of the fruits grown in open-field sunlight. Thus, our data supported the conclusion that the agrivoltaic system, in the context of climate change with the enduring drought and long-term water scarcity, can be a good adaptation strategy to maintain favorable tomato production compared to the full sunlight conditions. Furthermore, these results can be important for planning breeding programs, since in many cases, the tomato fruits grown in full sunlight were seedless.

Bio-Inoculation of Tomato (Solanum lycopersicum L.) and Jalapeño Pepper (Capsicum annuum L.) with Enterobacter sp. DBA51 Increases Growth and Yields under Open-Field Conditions

The rhizobacterium Enterobacter sp. DBA51 (DBA51), isolated from the semi-desert in Coahuila, Mexico, was previously found to increase the vegetative growth of tomato and tobacco plants cultivated under greenhouse conditions. The present report describes the results obtained from two independent open-field experiments performed with tomato and jalapeño pepper commercial crops inoculated with DBA51. Additionally, plants inoculated with Bacillus subtilis LPM1 (LPM1) and uninoculated plants were included as positive and negative controls, respectively. DBA51 and LPM1 significantly promoted growth at vegetative stages in the tomato plants; this effect was evident in the stem diameter (DBA51 with p < 0.0001 and LPM1 with p < 0.0001) and height (DBA51 with p < 0.0001 and LPM1 with p < 0.0001) of the tomato plants. However, no differences were detected in the jalapeño pepper plants. Additionally, DBA51 and LPM1 treatments increased tomato fruit production by 80% and 31%, respectively, compared to uninoculated plants. A similar increase in yield was recorded in DBA51- and LPM1-treated jalapeño pepper plants, which was 75% and 56% higher than uninoculated controls, respectively. These results strongly recommend the potential use of DBA51 as a biofertilizer in horticultural crops.

NaHCO3 impairs the growth and fruit yield of tomato plants

Underground water enriched in NaHCO3 is used in farms of the Buenos Aires province for tomato crop irrigation. This farming practice leads to salt accumulation and soil impairment after several seasons of cultivation inside the greenhouses. This work assayed the effect of NaHCO3 on tomato fruit production. Plants of the Elpida variety of Solanum lycopersicum L were grown in a hydroponic system. The presence of NaHCO3 (from 5 mM, as measured in the underground water to 10 or 20 mM) reduced K+/Na+ ratio and whole plant biomass and fruit yield; however, no effect was observed on fruit quality parameters. To test the participation of ascorbic acid in the tolerance to this stress, two slggp1 Micro-Tom mutant lines deficient in this antioxidant were used. In these experiments plants were treated with 0, 5 and 10 mM NaHCO3 causing an impairment of K+/Na+ ratio, photosynthesis, fruit yield, leaf and shoot dry weight (but without effect in root biomass) and delaying of fruit ripening time. Wild type and mutants plant responses showed no differences at stress conditions. Although NaHCO3 treatments caused a similar impairment in ascorbic acid mutants and wild type plants, these results reinforced the physiological importance of ascorbic acid levels to optimize plant growth under non-stressful conditions. Taken as a whole, the results presented here demonstrated the importance of avoiding the accumulation of this salt in greenhouse soils to optimize tomato production.

Effects of Glomus fasciculatum, Azotobacter chroococcum and Vermicompost Leachate on the Production and Quality of Tomato Fruit

Arbuscular mycorrhizal fungi, plant-growth-promoting bacteria (PGPB) and vermicompost constitute important environmental and economic resources for improving the production and quality of tomato fruits. The present research aims to determine the single and combined effect of Glomus fasciculatum (Gf) fungus, Azotobacter chroococcum (Azot), PGPB and vermicompost leachate (VL) organic fertilizer on the yield and quality of tomato fruit. Thus, an open-field experiment was established with seven treatments, a control and three replicates. Total soluble solids, vitamin C, acidity, fruit mass and fruit diameter were evaluated as fruit quality variables; the yield was recorded and estimated in tons per hectare−1. The results showed that Gf, Azot and VL were effective in promoting tomato yield and fruit quality. As a trend, the triple combination (Gf + Azot + VL) evidently obtained the highest values of total soluble solids, vitamin C and fruit acidity. The range of improvement concerning the fruit size was 66.6% (single treatment) compared to 78.5% (triple combination). The maximum yield of 54.5 t/ha−1 was recorded for the Gf + Azot + VL combination. Therefore, G. fasciculatum, A. chroococcum and VL are considered useful as organic alternatives for open-field tomato biofertilization programs in tropical countries.

Molecular characterizations of Verticillium dahliae isolates from grafted tomatoes grown in Antalya province of Türkiye

AbstractVerticillium wilt caused by soil‐borne fungus Verticillium dahliae results in serious quality, yield and economic losses in tomato fruit production in tomato‐growing areas around the world. In this study, V. dahliae isolates obtained from six different major grafted tomato production areas in Antalya province of Türkiye were characterized for races, pathotypes and vegetative compatibility groups using the specific PCR primers. Out of 66 isolates, 60 were determined to be race 2. Six isolates were not identified as race 1 or race 2. Fifty‐six isolates were determined as defoliating pathotypes (D) while 10 isolates were identified as non‐defoliating (ND) pathotypes. The isolates were clustered into four vegetative compatibility groups (VCGs): VCG1A (61), VCG2A or VCG4B (3), VCG2B (1) and VCG6 (1). According to the results of this study, the race 2, D pathotype and VCG1A isolates were dominant and widely distributed in the region. Additionally, the V. dahliae isolates fall into two major groups based on the dendrogram constructed from molecular data by Dice similarity index. The dendrogram showed significant diversity among the V. dahliae isolates particularly in the Elmalı region compared to other regions. The study is the first comprehensive research with the current disease and race 2 was identified for the first time in grafted tomatoes. These findings will lead to the development of V. dahliae‐resistant grafted tomatoes and breeding programs in Türkiye.

Responses of tomato hybrid cultivars to soil application of humic acid under greenhouse conditions

Abstract Responses of three tomato (Lycopersicon esculentum Mill.) hybrids viz. 'Luanova', 'Savarona' and 'Tessera' to various doses (0, 0.5, 1.0, 1.5 and 2.0 g L-1) of soil application of humic acid (HA) were evaluated in terms of plant growth, productivity and quality of fruits, under greenhouse conditions, during 2011-12 and 2012-13. In addition to improved quality characteristics, higher values for yield and yield components were recorded for tomato fruits harvested from plants of 'Tessera' cultivar compared to those harvested from other hybrids tested, regardless of growing seasons. Plants from 'Luanova' cultivar were, however, earlier in fruiting with higher number of fruits per plant. Soil application of HA presented positive effects on yield and physicochemical quality of tomato fruits irrespective of the dose of HA and the cultivar investigated, in both seasons. Soil application of HA at higher dose 1.5 g L-1 exhibited better results in all the three tomato cultivars tested, in terms of their vegetative and reproductive growth, and significantly improved the physicochemical quality of their fruits. Conclusively, the tomato hybrid 'Tessera' was found suitable for cultivation under greenhouse conditions while soil application of aqueous solution of HA @ 1.5 g L-1 substantially resulted in higher production of quality tomato fruits.

Isolation and Identification of Fungi Associated with Fruit Rot Disease of Tomato (Solanum lycopersicum L.) in the Southern Guinea Savannah, Nigeria

Rot disease is a major threat to tomato fruit production and postharvest handling in major tomato growing areas in Nigeria. Rotted tomato fruits were randomly collected from farmers’ farms for the purpose of isolation and identification of rot causing fungi in Tarka, Benue State, Nigeria between July and December, in 2015 and 2016. Results revealed that Aspergillus flavus, A. niger, Alternaria solani, Phytophthora infestans, Oidium neolycopersici, Sclerotium rolfsii, Fusarium oxysporum, Verticillium spp and Colletotrichum spp caused tomato fruit rot in the area. In both years, the lowest number of fungi was recorded in the months of July and December while the highest number was obtained in September. The mean number of fungi isolated showed that S. rolfsii was the least with 3.17 in 2015 and 1.66 in 2016 while F. oxysporum was the highest with 14.33 in 2015 and 9.33 in 2016. There were more fungi isolated in 2015 than in 2016. There were significant differences (P≤0.05) in the mean number of A. niger, P. infestans, O. neolycopersici and F. oxysporum isolated in both years. In conclusion, farmers should handle tomato fruits with care, to reduce postharvest injury and damage in order to ensure the availability of disease free fruits and to increase the output for the global population.

Cattle manure hydrochar posed a higher efficiency in elevating tomato productivity and decreasing greenhouse gas emissions than plant straw hydrochar in a coastal soil

Rehabilitation of degraded soil health using high-performance and sustainable measures are urgently required for restoring soil primary productivity and mitigating greenhouse gas (GHG) emission of coastal ecosystems. However, the effect of livestock manure derived hydrochar on GHG emission and plant productivity in the coastal salt-affected soils, one of blue carbon (C) ecosystems, was poorly understood. Therefore, a cattle manure hydrochar (CHC) produced at 220 °C was prepared to explore its effects and mechanisms on CH4 and N2O emissions and tomato growth and fruit quality in a coastal soil in comparison with corresponding hydrochars derived from plant straws, i.e., sesbania straw hydrochars (SHC) and reed straw hydrochars (RHC) using a 63-day soil column experiment. The results showed that CHC posed a greater efficiency in reducing the global warming potential (GWP, 54.6 % (36.7 g/m2) vs. 45.5–45.6 % (22.2–30.6 g/m2)) than those of RHC and SHC. For the plant growth, three hydrochars at 3 % (w/w) significantly increased dry biomass of tomato shoot and fruit by 12.4–49.5 % and 48.6–165 %, respectively. Moreover, CHC showed the highest promotion effect on shoot and fruit dry biomass of tomato, followed by SHC ≈ RHC. Application of SHC, CHC and RHC significantly elevated the tomato sweetness compared with CK, with the order of CHC (54.4 %) > RHC (35.6 %) > SHC (22.1 %). Structural equation models revealed that CHC-depressed denitrification and methanogen mainly contributed to decreased GHG emissions. Increased soil phosphorus availability due to labile phosphorus supply from CHC dominantly accounted for elevated tomato growth and fruit production. Comparably, SHC-altered soil properties (e.g., decreased pH and increased total carbon content) determined variations of GHG emission and tomato growth. The findings provide the high-performance strategies to enhance soil primary productivity and mitigate GHG emissions in the blue C ecosystems.

Double action plant growth promotion microorganisms in suppressing Fusarium wilt disease and increase tomato production

Fusarium oxysporum f.sp lycopersici is a fungus that causes wilt disease in tomatoes, attacking nurseries to mature plants. This study aims to examine several plant growth-promoting microorganisms (PGPM) to control Fusarium wilt and increase tomato production. The study was designed with a completely randomized design in a screen house with four treatments and three experimental units. The treatments tested were mycorrhiza 5 g per plant (M), a mixed solution containing Bacillus sp., Pseudomonas sp., and Trichoderma sp. 10 ml per plant (PGPM1), and combination treatment M and PGPM1 (PGPM2). The study showed a more extended incubation period of the pathogen-causing diseased plants with the treatment of PGPM2 compared to other treatments. The lower intensity of wilt disease was also found in the PGPM2 treatment. Consistently the same treatment also had a better effect on the number of leaves, plant height, and fresh tomato fruit production than other treatments. This study showed a significant effect of PGPM in controlling Fusarium wilt and increasing tomato production.

Tomato Fruit Quality as Affected by Ergonomic Conditions While Manually Harvested

The harvest phase plays an important role in the whole process of production of tomato fruit. Therefore, it is necessary to ensure a technological process that will not damage biological materials. The harvest phase plays an important role in the whole process. Many growers use special machines for harvesting, but there are fruits and vegetables that should be harvested manually to avoid damaging the surface or parenchyma tissue of the harvested objects. In addition to maintaining the quality of biological materials, work comfort, and ergonomic conditions for pickers should be ensured because inadequate working conditions do not encourage employees to undertake manual work in horticulture. Therefore, there have been shortages of workers on Polish plantations in the past year. Based on manual tomato harvesting, the authors conducted a matched qualitative research study on biological materials and work ergonomics. For this purpose, the Grip System was used to investigate tomato quality by assessing the impact of picking hand pressure (in three different picker’s body positions) on the harvested objects. Simultaneously, for the picker’s ergonomic analysis, a non-invasive surface electromyography method was used to precisely measure changes in muscle motor unit action in the picker’s wrist and lumbar spine while in three characteristic picker’s positions. The tests found that the poorest body position was when the body was deeply inclined and simultaneously twisted. No significant effect was shown of the body position of the tomato picker on the deterioration of the picked fruit quality. However, body positions significantly affect the level of physical load and work comfort.

A novel function of the tomato CALCINEURIN-B LIKE 10 gene as a root-located negative regulator of salt stress.

Climate change exacerbates abiotic stresses like salinization, negatively impacting crop yield, so development of strategies, like using salt-tolerant rootstocks, is crucial. The CALCINEURIN B-LIKE 10 (SlCBL10) gene has been previously identified as a positive regulator of salt tolerance in the tomato shoot. Here, we report a different function of SlCBL10 in tomato shoot and root, as disruption of SlCBL10 only induced salt sensitivity when it was used in the scion but not in the rootstock. The use of SlCBL10 silencing rootstocks (Slcbl10 mutant and RNAi line) improved salt tolerance on the basis of fruit yield. These changes were associated with improved Na+ and K+ homoeostasis, as SlCBL10 silencing reduced the Na+ content and increased the K+ content under salinity, not only in the rootstock but also in the shoot. Improvement of Na+ homoeostasis in Slcbl10 rootstock seems to be mainly due to induction of SlSOS1 expression, while the higher K+ accumulation in roots seems to be mainly determined by expression of LKT1 transporter and SlSKOR channel. These findings demonstrate that SlCBL10 is a negative regulator of salt tolerance in the root, so the use of downregulated SlCBL10 rootstocks may provide a suitable strategy to increase tomato fruit production under salinity.

An in-depth analysis of initial processing steps in the extraction of proteins from tomato (Solanum lycopersicum) leaves

Tomato leaves, the by-products from tomato production, are a promising source of proteins. An important challenge to extract proteins is that leaves are perishable materials. Here we investigated different post-harvest processing routes of tomato leaves (fresh processing, three-day storage, freezing, freeze drying and oven drying) to understand their effects on protein extractability from leaves. Proteins were extracted at floating pH and alkaline condition (pH 10). Obtained protein fractions were characterized according to protein solubility, protein profile, molecular weight distribution, secondary structure and color. Results showed that tomato leaves should be processed fresh for protein extraction. Alternatively, leaves can be stored for three-day at room temperature. Extraction at pH 10 did not result in enhanced protein extraction but led to dark brown color formation. Extensive protein degradation was induced during oven drying, providing a new processing route when degraded products such as peptides and free amino acids are the target products. Industrial relevanceTo support the transition of human diet from animal-based to plant-based, it is important to find new plant protein sources. Tomato leaves, the by-products of tomato fruit production, are widely available and are unexplored source of proteins. An additional challenge of using leaves as a protein source lies in the perishable nature of tomato leaves. The presented study discussed the post-harvest processing options to extract proteins from tomato leaves. Our findings provided insights on how to upscale protein extraction from tomato leaves in the future.

Can Soil Cover Affect the Performance, Yield, and Quality of Creeping Fresh Market Tomato Hybrids?

Soil cover is a major factor in the cultivation of creeping tomatoes, especially for in natura consumption. This study aimed to determine the combination of a suitable tomato hybrid and soil cover, resulting in superior production performance and quality attributes of tomato fruits. Tomato hybrids (Fascínio and Thaíse) were cultivated on five soil cover types (uncovered soil, plastic mulch, sorghum, Sudan grass, and pearl millet). The data were submitted to a principal component analysis (PCA), considering all the variables, through Biplot graphical analysis. A Pearson correlation analysis was performed at the 5% significance level. For biomass production, pearl millet and Sudan grass were distinguished from the other soil covers, showing lower decomposition rates and, consequently, longer half-lives. Covering with plastic mulch provided higher total (111 t ha−1) and commercial (74.4 t ha−1) yields, regardless of the analyzed hybrid. According to the PCA, soil cover management influences the production and quality of tomato fruits, except for chemical and post-harvest characteristics, and maintains ideal levels for commercialization for all treatments. The Fascínio hybrid presented better production attributes, higher total and commercial fruit production per plant as well as fruits with larger sizes, especially when grown in plastic mulch cover. The Fascínio hybrid also presented fruits with higher levels of bioactive compounds (lycopene and β-carotene).

Influences of NPSB and Vermicompost Application Rates on Yields of Tomato (Lycopersicon esculentum Mill) at Jimma Ganati Research Site of Wallaga University, Western Ethiopia

The tomato (Lycopersicon esculentum Mill) is an important vegetable crop in Ethiopia and is produced and eaten in large quantities throughout the nation. However, the tomato production is quite low (10 tons·ha−1) compared to the global average yield of 34 tons·ha−1 due to the repetitive use of chemical fertilizers alone, growing intensive crops that are absorbing significant amounts of the soil nutrients, and the lack of application of organic fertilizers. Therefore, it is crucial to take accurate measurements when using fertilizers in order to solve issues and boost crop yield. The study’s objective was to find out how NPSB and vermicompost fertilizers together influenced tomato growth, yield characteristics, and yield at the Wallaga University Research Site for two consecutive years (2021 and 2022). The experiment used a factorial randomized block design with two components: four levels of NPSB and four levels of vermicompost. The tomato fruit production and all of its components were strongly impacted by the primary and interaction effects of NPSB and vermicompost treatment rates. The highest fruit length was 6.26 cm, the largest fruit diameter was 5.94 cm, the shoot fresh weight was 48.25 g·plant−1, the shoot dry weight was 4.50 g·plant−1, the marketable fresh fruit per plant was 5.54 kg, and the fruit yield was 24.36 ton·ha−1 after the application of 125 kg·ha−1 NPSB plus 8 ton·ha−1 vermicompost. Application of 125 kg·ha−1 of NPSB fertilizer along with 8 tons·ha−1 of vermicompost increases net benefits by 115922.5 ETB·ha−1 as compared to a control. Therefore, in order to enhance tomato yield, it may be suggested that farmers utilize the combination of 125 kg·ha−1 of NPSB and 8 tons·ha−1 of vermicompost rather than applying any inorganic fertilizers alone.

SlMAPK3 Positively Regulates the Ethylene Production of Postharvest Tomato Fruits and Is Involved in Ethylene-Mediated Cold Tolerance.

Mitogen-activated protein kinase (MAPK) cascades and ethylene are crucial for plant growth, development, and stress responses, but their potential mechanisms in cold resistance remain unclear. We revealed that SlMAPK3 transcript levels were dramatically induced by cold treatment in an ethylene-dependent manner. Under cold stress, the proline content of SlMAPK3-overexpression fruit was 96.5 and 115.9% higher than that of wild-type fruit (WT), respectively, while the ion leakage was 37.3 and 32.5% lower than that of WT. RNA sequencing revealed that overexpression of SlMAPK3 caused upregulation of genes that are enriched in the ethylene-activated signaling pathway (GO:0009873), cold signaling pathway (GO:0009409), and heat signaling pathway (GO:0009408). RT-qPCR demonstrated that the expression levels of SlACS2, SlACS4, SlSAHH, SlCBF1, SlDREB, SlGolS1, and SlHSP17.7 in the OE.MAPK3 fruits were consistent with the RNA sequencing results. Meanwhile, the knockout of SlMAPK3 reduced the ethylene content, ACC content, and ACS activity. Moreover, the knockout of SlMAPK3 reduced the positive effect of ethylene in cold stress, while suppressing the expression of SlICE1 and SlCBF1. In conclusion, our study demonstrated a novel mechanism by which SlMAPK3 positively regulates the ethylene production of postharvest tomato fruits and is involved in ethylene-mediated cold tolerance.

Improvement of Nutritional Quality of Tomato Fruit with Funneliformis mosseae Inoculation under Greenhouse Conditions

Long-term soil mining with extensive cultivation practices and traditional breeding methods have declined the flavor and nutritional value of tomatoes. Apart from important mineral nutrients (i.e., nitrogen, phosphorus, and potassium), fungi known as arbuscular mycorrhizae (AM) can considerably improve the quality of agricultural production through higher phosphate uptake. Using hydroponically cultured commercially available tomato cultivars, we investigated the possible effects of mycorrhizae in improving the nutritional quality of tomato fruit. Funneliformis mosseae (syn. Glomus mosseae)-inoculated tomato plants were grown on a 1:1 mixture of peat and vermiculite, and different phosphorus levels were applied. RNAseq and metabolites were studied to confirm the relative gene expression and metabolites in fruit tissues. The results showed that AM inoculation with low phosphorus can significantly improve important fruit-quality traits such as free amino acids, lycopene (47.9%), and β-carotene (29.6%) without compromising the yield. Further, differentially expressed genes (DEGs) were identified by comparing the nutritional and ripening potential of fruits produced by mycorrhizal and non-mycorrhizal plants. Notably, carotenoids and sugars (BRIX values) were found to be higher in mycorrhized plants in contrast to non-mycorrhized plants. Therefore, the current study suggests mycorrhization as a promising approach for the production of high-quality tomato fruit for human consumption.