Tomato Solanum Lycopersicum Research Articles

Prone to loss: Senescence-regulated protein degradation leads to lower protein extractability in aging tomato leaves

The utilization of proteins extracted from tomato (Solanum lycopersicum) leaves as cost-effective resources for human consumption or animal feed has gained interest. Thus, increasing protein extractability from tomato leaves became a new breeding target. However, the genetic factors influencing this trait remains poorly understood. In this study, we analyzed changes in leaf protein content, protein composition, and extraction yield across developmental stages, which are vegetative growth, flowering, fruit-forming, and mature fruit. Moreover, tomato gene expression across developmental stages was also studied, to identify genes underlying variability in leaf protein extraction. Protein extraction yield decreased from 0.51 g/g to 0.01 g/g leaf protein from the vegetative to mature stage. However, total protein content inferred with Dumas combustion analysis did not change over the developmental stages tested, while the protein-to-peptide ratio decreased significantly. To further analyze potential causes underlying the decline of protein-to-peptide ratio, the enzymatic activity of proteases – i.e. the enzymes responsible for protein degradation – and the expression of genes encoding these enzymes was studied along plant development. The overall specific activity of proteases did not change significantly throughout plant development. On the contrary, the gene expression of distinct members of the aspartic, cysteine, and subtilase protease families increased. Overall, our findings suggest that extraplastidic protein degradation likely underlies the protein degradation observed during senescence. In the future, the reduction of the activity of extraplastidic proteases through biotechnology could represent an effective strategy to develop tomato varieties with improved protein extraction yields.

SlMKK4 is responsible for pollen development in tomato

The development of viable pollen is a determinant of male fertility and plays an essential role in the reproductive process of angiosperms. Mitogen-activated protein kinase (MAPK) cascades modulate diverse aspects of plant growth, but their involvement in post-meiotic pollen development is unclear. In this study, SlMKK4 was identified as a crucial regulator in overseeing pollen development in tomatoes (Solanum lycopersicum). Utilizing CRISPR-associated protein 9 to disrupt SlMKK4 resulted in an obvious decrease in pollen viability. The results of cell biology and transcriptomic analyses demonstrated that SlMKK4 specifically regulates auxin and sugar metabolism as well as signal transduction during post-meiotic pollen development. This is supported by the finding that protein–protein interaction assays and in vitro phosphorylation assays indicate that SlMKK4 serves as the upstream MAPKK for SlMPK20, which exhibits a distinct function in regulating the uninucleate (UN) to binucleate (BN) transition during microgametogenesis in tomatoes. Moreover, pollen from transgenic plants experienced significant arrest predominantly at the BN stage, accompanied by subcellular abnormalities manifesting during the late UN microspore phase. Furthermore, transcriptomic analyses indicated that SlMKK4 knockout remarkably downregulated the expression of numerous genes regulating auxin and sugar metabolism as well as signal transduction in anthers. Therefore, our findings suggest that SlMKK4 may serve as one of the upstream SlMAPKKs of SlMPK20 and also play a pivotal role in modulating post-meiotic pollen development in tomato plants.

Different multicellular trichome types coordinate herbivore mechanosensing and defense in tomato.

Herbivore-induced wounding can elicit a defense response in plants. However, whether plants possess a surveillance system capable of detecting herbivore threats and initiating preparatory defenses before wounding occurs remains unclear. In this study, we reveal that tomato (Solanum lycopersicum) trichomes can detect and respond to the mechanical stimuli generated by herbivores. Mechanical stimuli are preferentially perceived by long trichomes, and this mechanosensation is transduced via intra-trichome communication. This communication presumably involves calcium waves, and the transduced signals activate the jasmonic acid (JA) signaling pathway in short glandular trichomes, resulting in the upregulation of the Woolly (Wo)-SlMYC1 regulatory module for terpene biosynthesis. This induced defense mechanism provides plants with an early warning system against the threat of herbivore invasion. Our findings represent a perspective on the role of multicellular trichomes in plant defense and the underlying intra-trichome communication.

A Novel Enterococcus-Based Nanofertilizer Promotes Seedling Growth and Vigor in Wheat (Triticum aestivum L.).

Excessive use of chemical fertilizers poses significant environmental and health concerns. Microbial-based biofertilizers are increasingly being promoted as safe alternatives. However, they have limitations such as gaining farmers' trust, the need for technical expertise, and the variable performance of microbes in the field. The development of nanobiofertilizers as agro-stimulants and agro-protective agents for climate-smart and sustainable agriculture could overcome these limitations. In the present study, auxin-producing Enterococcus sp. SR9, based on its plant growth-promoting traits, was selected for the microbe-assisted synthesis of silver nanoparticles (AgNPs). These microbial-nanoparticles SR9AgNPs were characterized using UV/Vis spectrophotometry, scanning electron microscopy, and a size analyzer. To test the efficacy of SR9AgNPs compared to treatment with the SR9 isolate alone, the germination rates of cucumber (Cucumis sativus), tomato (Solanum lycopersicum), and wheat (Triticum aestivum L.) seeds were analyzed. The data revealed that seeds simultaneously treated with SR9AgNPs and SR9 showed better germination rates than untreated control plants. In the case of vigor, wheat showed the most positive response to the nanoparticle treatment, with a higher vigor index than the other crops analyzed. The toxicity assessment of SR9AgNPs demonstrated no apparent toxicity at a concentration of 100 ppm, resulting in the highest germination and biomass gain in wheat seedlings. This work represents the first step in the characterization of microbial-assisted SR9AgNPs and encourages future studies to extend these conclusions to other relevant crops under field conditions.

Effects of dynamised high dilutions and vegetal extract based on silicon on the growth and induction of resistance in tomato plants against Rhizoctonia solani

ABSTRACT The objective of this study was to study the response of tomato (Solanum lycopersicum) against Rhizoctonia solani using dynamised high dilutions and plant extract based on silicon. The treatments were Silicea terra (ST), Thuya occidentalis (TO), and Equisetum arvense (EA) at 30CH (Centesimal Hahnemannian dilution order), Equisetum arvense leaf extract (LE), and non-dynamised water as the control. Seeds of tomato cv Marmande were treated overnight. The in vitro bioassays involved assessment of R. solani mycelial growth, seed germination, and seedling development. In the greenhouse experiment, the emergence, root and aerial part development, and disease development were evaluated. Leaves were harvested to analyse concentrations of flavonoids, phenolic compounds, chlorophyll, carotenoids, and chitinase activity. In the in vitro bioassay, LE reduced mycelial growth and TO increased the seedling vigour index, dry weight, and length of seedlings. In the greenhouse experiment, TO and ST increased plant emergence. Tomato plants treated with ST improved the fresh weight and the length of the roots. The disease severity was decreased by ST, LE, and TO. The flavonoid concentration was higher in plants treated with TO and LE. Overall, the treatments of TO, EA, and ST improved the content of phenolic compounds. Moreover, endochitinase and chitobiosidase were activated by LE.

Immunomodulating melatonin-decorated silica nanoparticles suppress bacterial wilt (Ralstonia solanacearum) in tomato (Solanum lycopersicum L.) through fine-tuning of oxidative signaling and rhizosphere bacterial community

BackgroundTomato (Solanum lycopersicum L.) production is severely threatened by bacterial wilt, caused by the phytopathogenic bacterium Ralstonia solanacearum. Recently, nano-enabled strategies have shown tremendous potential in crop disease management.ObjectivesThis study investigates the efficacy of biogenic nanoformulations (BNFs), comprising biogenic silica nanoparticles (SiNPs) and melatonin (MT), in controlling bacterial wilt in tomato.MethodsSiNPs were synthesized using Zizania latifolia leaves extract. Further, MT containing BNFs were synthesized through the one-pot approach. Nanomaterials were characterized using standard characterization techniques. Greenhouse disease assays were conducted to assess the impact of SiNPs and BNFs on tomato plant immunity and resistance to bacterial wilt.ResultsThe SiNPs and BNFs exhibited a spherical morphology, with particle sizes ranging from 13.02 nm to 22.33 nm for the SiNPs and 17.63 nm to 21.79 nm for the BNFs, indicating a relatively uniform size distribution and consistent shape across both materials. Greenhouse experiments revealed that soil application of BNFs outperformed SiNPs, significantly enhancing plant immunity and reducing bacterial wilt incidence by 78.29% in tomato plants by maintaining oxidative stress homeostasis via increasing the activities of antioxidant enzymes such as superoxide dismutase (31.81%), peroxidase (32.9%), catalase (32.65%), and ascorbate peroxidase (47.37%) compared to untreated infected plants. Additionally, BNFs induced disease resistance by enhancing the production of salicylic acid and activating defense-related genes (e.g., SlPAL1, SlICS1, SlNPR1, SlEDS, SlPD4, and SlSARD1) involved in phytohormones signaling in infected tomato plants. High-throughput 16 S rRNA sequencing revealed that BNFs promoted growth of beneficial rhizosphere bacteria (Gemmatimonadaceae, Ramlibacter, Microscillaceae, Anaerolineaceae, Chloroplast and Phormidium) in both healthy and diseased plants, while suppressing R. solanacearum abundance in infected plants.ConclusionOverall, these findings suggest that BNFs offer a more promising and sustainable approach for managing bacterial wilt disease in tomato plants.Graphical

Brinjal (Solanum melongena) rootstocks improve photosynthetic rate, fruit yield and quality parameters in grafted tomato (Solanum lycopersicum)

The experiment was conducted during winter (rabi) seasons of 2021–22 and 2022–23 at ICAR-Indian Institute of Vegetable Research, Varanasi, Uttar Pradesh to study the improvement in yield and quality parameters in tomato (Solanum lycopersicum L.) cultivar using brinjal (Solanum melongena L.) rootstock. Three improved cultivars of tomatoes i.e. Kashi Aman, Kashi Adarsh and Kashi Chayan were grafted over three brinjal rootstocks, IC-111056, IC- 354557, and Surya. Experimental findings revealed that brinjal rootstocks significantly affected photosynthetic traits, root architectures, fruit yields and quality traits of tomatoes. Maximum photosynthetic rate (23.8 µmol/m2/s) and stomatal conductance (492.74 mmol/m2/s) were recorded in Kashi Chayan grafted over Surya rootstock, whereas chlorophyll fluorescence yields (Fv/Fm) was significantly higher in Kashi Aman self-rooted plants (0.452–0.457). Grafting tomato onto brinjal rootstocks significantly enhanced most of the yield traits, such as fruit number, weight, size and yields. Surya + Kashi Chayan graft combination registered an enhancement in number of fruits and yields by 8.65% and 8.4%, respectively over self-rooted Kashi Chayan. Significantly higher root volumes were noticed in two graft combinations i.e. IC-354557 + Kashi Aman (28.53 cm2) and Surya + Kashi Chayan (27.98 cm2), while 63% and 44.5% higher root length density (RLD) were registered in graft combinations IC-354557 + Kashi Chayan and Surya + Kashi Chayan, respectively over self-rooted Kashi Chayan. Fruit quality such as lycopene and ascorbic acid contents were significantly affected in different rootstocks and scions, whereas fruit acidity was unaffected. From the present study it may be conclude that use of brinjal rootstock Surya significantly improved most of the physiological, yield, root architecture and fruit quality in Kashi Chayan tomato cultivars.

Enhanced growth and yield in semi-indeterminate tomato (Solanum lycopersicum): A heterosis study under protected condition

A diallel design was employed to assess the magnitude of heterosis, aiming to improve growth and yield of semi- indeterminate tomato by identifying the desirable cross- combinations. Five semi-indeterminate tomato genotypes (VRT13, EC15127, EC362941, EC521061 and EC521069) were crossed in diallel mating fashion during rainy (kharif) season of 2020. Crosses and the parents were examined for heterosis studies under naturally ventilated polyhouse during winter (rabi) season of 2020–21. The results revealed the presence of heterotic vigour in the growth and yield characteristics of the hybrids with significant differences among the traits studied. Hybrids from crosses EC15127 × EC362941 and VRT13 × EC362941 resulted negative heterosis over mid and better parent, respectively for days to first flowering indicating their earliness for flowering. VRT13 × EC15127 and EC15127 × EC362941 noticed heterosis over better and mid parent, respectively for fruit yield. Based on overall performance, the cross combinations EC15127 × EC362941, VRT13 × EC521061, VRT13 × EC15127, VRT13 × EC362941 and EC521069 × EC362941 were performed best over their parents for growth and yield parameters. Hence, these hybrids can be exploited directly or can be used further for development of improved commercial lines

Convergent emergence of Glucomannan β-galactosyltransferase activity in Asterids and Rosids.

β-Galactoglucomannan (β-GGM) is a primary cell wall polysaccharide in rosids and asterids. The β-GGM polymer has a backbone of repeating β-(1,4)-glucosyl and mannosyl residues, usually with mono- α-(1,6)-galactosyl substitution or β-(1,2)-galactosyl α-galactosyl disaccharide sidechains on the mannosyl residues. Mannan β-GalactosylTransferases (MBGTs) are therefore required for β-GGM synthesis. The single MBGT identified so far, AtMBGT1, lies in glycosyltransferase family 47A subclade VII, and was identified in Arabidopsis. However, despite the presence of β-GGM, an orthologous gene is absent in tomato (Solanum lycopersicum), a model asterid. In this study, we screened candidate MBGT genes from the tomato genome, functionally tested the activities of encoded proteins, and identified the tomato MBGT (SlMBGT1) in GT47A-III. Interestingly therefore, AtMBGT1 and SlMBGT1 are located in different GT47A subclades. Further, phylogenetic and glucomannan structural analysis from different species raised the possibility that various asterids possess conserved MBGTs in an asterid-specific subclade of GT47A-III, indicating that MBGT activity has been acquired convergently among asterids and rosids. The present study highlights the promiscuous emergence of donor and acceptor preference in GT47A enzymes. The independent acquisition of the activity also suggests an adaptive advantage for eudicots to acquire β-GGM β-galactosylation, and hence also suggests the disaccharide side chains are important for β-GGM function.

Comparative assessment of fresh and processed tomato (Solanum lycopersicum) pulps: Impact of processing on physicochemical, antioxidant, and enzymatic behavior

This study investigated the impact of chemical and thermochemical treatment on the physicochemical, antioxidant, and enzymatic behavior of tomato pulp. The chemical treatment involved the use of 0.05 % potassium metabisulfite, 0.05 % sodium metabisulfite, 0.05 % potassium sorbate, 0.05 % sodium benzoate, 0.5 % ascorbic acid, and 1 % citric acid, whereas the thermochemical treatment involved heating the tomato pulp to 80–82 °C for 30 min before applying the same chemical preservatives, followed by storage at 30±1 °C for 120 days. The results revealed that the thermochemically treated sample retained higher levels of total phenol content (6.24–4.10 mgGAE/100 g), vitamin C (136.43–54.05mg/100 g), and a lower level of lycopene content (59.87–43.28µg/100 g) compared to chemically treated samples. Additionally, the thermochemically treated sample had higher TSS (6.57 to 6.70°Brix), increased acidity (1.60 % to 1.06 %), lower pH (4.11–3.57), better color stability, and reduced browning. Moreover, it showed improved oxidoreductase and hydrolase enzymatic control during storage. Therefore, the idea of thermochemical treatment can be a milestone in improving the shelf life of tomato pulp to benefit the food industry.

The Optimal Drought Hardening Intensity and Salinity Level Combination for Tomato (Solanum lycopersicum L.) Cultivation under High-Yield, High-Quality and Water-Saving Multi-Objective Demands.

The extreme weather and the deteriorating water environment have exacerbated the crisis of freshwater resource insufficiency. Many studies have shown that salty water could replace freshwater to partly meet the water demand of plants. To study the effects of early-stage drought hardening and late-stage salt stress on tomatoes (Solanum lycopersicum L.), we conducted a 2-year pot experiment. Based on the multi-objective demands of high yield, high quality, and water saving, yield indicators, quality indicators, and a water-saving indicator were selected as evaluation indicators. Three irrigation levels (W1: 85% field capacity (FC), W2: 70% FC, W3: 55% FC) and three salinity levels (S2: 2 g/L, S4: 4 g/L, S6: 6 g/L) were set as nine treatments. In addition, a control treatment (CK: W1, 0 g/L) was added. Each treatment was evaluated and scored by principal component analysis. The results for 2022 and 2023 found the highest scores for CK, W2S2, W3S2 and CK, W2S4, W2S2, respectively. Based on response surface methodology, we constructed composite models of multi-objective demands, whose results indicated that 66-72% FC and 2 g/L salinity were considered the appropriate water-salt combinations for practical production. This paper will be beneficial for maintaining high yield and high quality in tomato production using salty water irrigation.

Effect of Plant Growth Regulators on Growth and Yield of Tomato (Solanum lycopersicum L.) Cv. MAHY 701 under Agroclimatic Conditions of Bhubaneswar

Exogenous application of plant growth regulators play a vital role on effectively enhancing plant growth along with crop output. In order to determine the effect of plant growth regulators and the ideal concentration of GA₃ and NAA for improved tomato growth and yield (Solanum lycopersicum L.) cv. MAHY-701 under Bhubaneswar condition, a field experiment was conducted in Rabi 2022 at Agricultural Research Station, Binjhagiri, Institute of Agricultural Sciences, Siksha "O" Anusandhan (Deemed to be) University, Bhubaneswar, Odisha using plant growth regulators, namely GA₃ and NAA. The experimental design was randomized block design, which consisted of three replications and seven treatments. When compared to the control treatment, all growth, yield, and quality parameters were shown to be significantly better at various concentrations of GA₃ (30, 60, and 90 ppm) and NAA (25, 50, and 75 ppm). The findings of the investigation reinforce the claim that, as compared to the control, tomato growth and yield were considerably affected by both GA₃ and NAA. The results categorically demonstrated that the treatment where the plant was sprayed with GA₃ @ 90 ppm had the highest total soluble solids (4.33°Brix), acidity (0.42%), and shelf life (18.73), as well as the highest number of fruits per plant (42.90), fruit length (6.40cm), fruit diameter (6.80cm), weight of fruit (118.80g), yield per plot (31.70kg), yield per ha. (423.50qt), and other quality attributes. In conclusion, farmers may be suggested to apply GA₃ at 90 ppm and NAA at 50 ppm when raising tomatoes in Bhubaneswar Agroclimatic environments for MAHY-701.

Biological and Molecular Characterization of a New Isolate of Tomato Mottle Mosaic Virus Causing Severe Shoestring and Fruit Deformities in Tomato Plants in India

Tomato (Solanum lycopersicum L.), the second most important vegetable crop globally, faces a significant threat from various viral diseases. A newly emerging disease, characterised by distinctive shoestring symptoms on leaves and the development of unripe, small, and hard fruit, poses a serious challenge to tomato cultivation in India. An initial survey in an experimental field revealed more than 50% of the plants displayed symptoms of the shoestring disease, resulting in substantial reductions in fruit yield and quality. Transmission electron microscopy (TEM) and molecular analyses identified an isolate of the tomato mottle mosaic virus (ToMMV) in the affected plants. When the partially purified virus was mechanically inoculated into tomato cv. Pusa Ruby plants, it reproduced the characteristic shoestring symptoms, confirming its causal relationship with the disease. Notably, the present shoestring isolate of ToMMV (ToMMV-Tss) was found to induce similar shoestring symptoms in most of the major commercial tomato varieties when inoculated under controlled experimental conditions in the glasshouse, indicating its aggressive nature. Host range studies demonstrated that the ToMMV-Tss can infect several solanaceous species, while cucurbitaceous hosts remained unaffected. Moreover, the virus was found to be seed-transmissible, with a small percentage of seedlings from infected plants displaying symptoms. These findings underscore the significant impact of ToMMV on tomato production in India and emphasise the need for reliable diagnostic tools and effective management strategies to curb the spread and mitigate the impact of this virus on commercial tomato cultivation.

Microclimate monitoring in commercial tomato (Solanum Lycopersicum L.) greenhouse production and its effect on plant growth, yield and fruit quality

IntroductionHigh annual tomato yields are achieved using high-tech greenhouse production systems. Large greenhouses typically rely only on one central weather station per compartment to steer their internal climate, ignoring possible microclimate conditions within the greenhouse itself.MethodsIn this study, we analysed spatial variation in temperature and vapour pressure deficit in a commercial tomato greenhouse setting for three consecutive years. Multiple sensors were placed within the crop canopy, which revealed microclimate gradients.Results and discussionDifferent microclimates were present throughout the year, with seasonal (spring – summer – autumn) and diurnal (day – night) variations in temperature (up to 3 °C, daily average) and vapour pressure deficit (up to 0.6 kPa, daily average). The microclimate effects influenced in part the variation in plant and fruit growth rate and fruit yield – maximum recorded difference between two locations with different microclimates was 0.4 cm d-1 for stem growth rate, 0.6 g d-1 for fruit growth rate, 80 g for truss mass at harvest. The local microclimate effect on plant growth was always larger than the bulk climate variation measured by a central sensor, as commonly done in commercial greenhouses. Quality attributes of harvested tomato fruit did not show a significant difference between different microclimate conditions. In conclusion, we showed that even small, naturally occurring, differences in local environment conditions within a greenhouse may influence the rate of plant and fruit growth. These findings could encourage the sector to deploy larger sensor networks for optimal greenhouse climate control. A sensor grid covering the whole area of the greenhouse is a necessity for climate control strategies to mitigate suboptimal conditions.

Practical application of heterosis on yield evidence and fruits biochemical composition for tomato (Solanum lycopersicum L.) in open ground

Relevance. The research is devoted to studying the peculiarities of the high-parent heterosis manifestation which connected with yield traits and the biochemical composition of tomato fruits.Materials and Methods. The work was carried out in 2021–2023 in open field conditions on the experimental plot of the Belarusian State Agricultural Academy (Mogilev region, Belarus). The objects of research were 30 F1 hybrids and 11 parental forms with different levels of economically valuable traits and with the specific set of genes for pathogen resistance and lycopene accumulation. The aim of the research was to create high-yield heterotic F1 tomato hybrids, adapted to open field conditions in Belarus, with a valuable biochemical composition of fruits.Results. The best hybrid combinations showed an early yield of 0.90–2.49 kg/m2, a marketable yield of 7.50–11.40 kg/m2, and a total yield of 8.22–13.12 kg/m2. High heterosis effect was established for early (88.9–291.0%), marketable (36.0–111.2%), and total (28.6–97.8%) yield in some hybrids. Significant differences in the accumulation of dry matter, carotene, and soluble carbohydrates were ascertained between the hybrids. Hybrid combinations with the highest value of true heterosis on accumulation of dry matter (18.3–21.6%), carotene (20.2–22.9%), and soluble carbohydrates (15.7–38.9%) were identified. Inheritance of early, marketable and total yield, dry matter content, carotene and soluble carbohydrates predominantly took place according to the positive overdominance, fruit weight – according to the intermediate inheritance, vitamin C content – according to the negative overdominance. Hybrids Brusnichny F1, Mansiata F1, Rada F1 were transferred to the State Inspection for Testing and Protection of Plant Varieties of the Republic of Belarus and successfully passed the testing stage in 2023.

The role of SlCHRC in carotenoid biosynthesis and plastid development in tomato fruit

Chromoplasts are specialized plastids in plants involved in carotenoid synthesis, accumulation, and stress resistance. In tomatoes (Solanum lycopersicum), the Chromoplast-associated carotenoid binding protein (CHRC) regulates chromoplast development and carotenoid accumulation, although its precise mechanisms are not yet fully understood. To investigate the role of SlCHRC in carotenoid biosynthesis, we generated transgenic tomatoes using overexpression (oe-SlCHRC) and CRISPR/Cas9-mediated gene editing (cr-SlCHRC) techniques. The results demonstrated inhibited fruit ripening and delayed onset of color break in both transgenic lines. The oe-SlCHRC lines exhibited increased carotenoid accumulation, particularly (E/Z)-phytoene, lycopene, and γ-carotene, with abundant plastoglobules and carotenoid crystals observed via TEM. In contrast, cr-SlCHRC mutants showed a greener phenotype, reduced carotenoid content, and fewer plastoglobules at the BK + 10 stage. Transcriptome analysis indicated that SlCHRC influences key genes in carotenoid biosynthesis, such as SlNCED2, as well as genes related to chloroplast development, photosynthesis, and plastoglobule formation. Additionally, SlCHRC enhances heat stress tolerance in tomato fruits by upregulating heat shock proteins (HSPs), antioxidants, and proline accumulation. These findings indicate that SlCHRC plays a crucial role in improving tomato fruit quality under heat stress conditions.

Brassinosteroids mediate arbuscular mycorrhizal symbiosis through multiple potential pathways and partial identification in tomato

Currently, little is known regarding the specific processes through which brassinosteroids (BR) affect arbuscular mycorrhizal (AM) symbiosis. Understanding this relationship is vital for advancing plant physiology and agricultural applications. In this study, we aimed to elucidate the regulatory mechanisms of BR in AM symbiosis. According to the log2 fold change-value and adjP-value, we integrated the common differentially expressed genes (DEGs) in maize (Zea mays L.) treated with BR and AM, Arabidopsis (Arabidopsis thaliana) mutants deficient in BR receptors, and tomato (Solanum lycopersicum) plants inoculated with AM fungi. In addition, we characterized the symbiotic performance of tomato plants with BR receptor defects and overexpression. The results indicated that the common differential genes induced by BR and AM were involved in metabolic processes, such as cell wall modification, cytoskeleton remodeling, auxin and ethylene signaling, photosynthesis, mineral nutrient transport, and stress defense. Specifically, these include the BR1 gene, which modifies the cell wall. However, the fungal colonization rate of BR receptor-deficient tomato plants was significantly reduced, and the total phosphorus concentration was increased. Conversely, the performance of the overexpressing tomato transformation plants demonstrated a significant contrast. Additionally, the mild rescue of mycorrhizal attenuation in mutants treated with exogenous BR suggests the possibility of direct feedback from BR synthesis to AM. Notably, the cell wall modification gene (SlBR1) and calcium spike gene (SlIPD3) were induced by both BR and AM, suggesting that BR may influence cell penetration during the early stages of AM colonization. Synthesis: Our results demonstrated that BR positively regulates AM symbiosis through multiple pathways. These findings pave the way for future research, including isolation of the individual contributions of each pathway to this complex process and exploration of possible agricultural applications.

The role of biochar nanoparticles in reducing salt stress in tomato (Solanum lycopersicum) plants grown in fields

Soil salinization is a major threat to global food security, affecting over 20 % of cultivated land and reducing yields of important crops like tomato (Solanum lycopersicum). This field study explored the potential of biochar nanoparticles (BNPs) derived from rice straw to mitigate salt stress in tomato plants. The BNPs, prepared by pyrolysis at 350 ℃ and ball milling, had an average size of 130.32 nm. Tomato plants were grown for 12 weeks in soil with 0.2 % NaCl (w/w) and BNPs at 0.5, 1, or 2 ‰ w/w. Controls included unamended soil, soil with NaCl only, soil with BNPs only, and regular biochar with and without NaCl. BNPs significantly improved growth, biomass, and fruit yield of salt-stressed tomato plants. The 2 ‰ BNP treatment increased fruit yield by 115.05 % compared to salt stress alone. Stem fresh and dry weights increased by 35.64 % and 79.71 %, respectively, while root fresh and dry weights increased by 138.27 % and 68.35 %, respectively. BNPs enhanced fruit quality, with higher concentrations showing better effects. BNPs alleviated salt stress by regulating ion homeostasis, limiting Na translocation to leaves and fruits (reducing Na content by 35.15 % in leaves and 16.06 % in fruits), improving K content and Na/K ratio, and influencing Mg and P absorption and translocation. The nanoscale size, high surface area, and enhanced reactivity of BNPs allow them to penetrate plant tissues and interact with ion transport components. This study demonstrates the potential of BNPs as a sustainable approach for enhancing tomato salt tolerance in the field. Using crop residues for BNP production supports circular economy and sustainable agriculture. This approach holds potential for enhancing sustainable crop production under saline conditions, contributing to food security and the development of resilient agricultural systems in challenging environments.

Micropropagation of Selected Hybrid Tomato (Solanum lycopersicum L.) Varieties Using Shoot Tip Culture

Tomato (Solanum lycopersicum L.) is one of the most important vegetable crops in the world. The use of hybrid varieties is a great option to increase its production but using F2 seed leads to lack of uniformity as a result of segregation. Therefore mass propagation using tissue culture could help to solve these problems. The objective of this study was to develop an optimum micropropagation protocol for Valouro, Uwezo and Shelter hybrid tomato varieties using shoot tip culture. Three successive experiments: shoot initiation; shoot multiplication and root inductions were conducted. Different concentrations of BAP (0.0, 0.25, 0.5, 0.75, 1.0 and 1.25 mg/l) and (0.0, 0.5, 1.0, 1.5, 2.0, 2.5 and 3 mg/l) were used for shoot initiation and shoot multiplication, respectively. While different concentrations of IBA (0.0, 0.25, 0.5, 0.75, 1.0, 1.25 and 1.5 mg/l) were used for root induction. The three separate experiments were laid out as factorial arranged in completely randomized design. The result of shoot initiation showed that the interaction of BAP*Varieties highly significant (P<0.01) effect. In the multiplication experiment, all parameters showed highly significant difference (P<0.01). In rooting experiment the interaction effect of IBA*Variety showed highly significant difference for the studied parameters. In conclusion MS medium without growth regulators was the optimum for shoot initiation. For shoot multiplication experiment 2mg/l, 0.5mg/l and 1.5mg/l of BAP was the optimum concentration for number of shoots per explant, shoot length, and leaf number respectively. For in vitro rooting MS medium containing 0.5 mg/l IBA was optimum for all varieties.

SlSTOP1-regulated SlHAK5 expression confers Al tolerance in tomato by facilitating citrate secretion from roots

Abstract SENSITIVE TO PROTON RHIZOTOXICITY 1 (STOP1) is a core transcription factor that regulates the expression of aluminum (Al)-resistance genes to manage Al toxicity in plants. However, the genome-wide roles of SlSTOP1 in the Al stress response of tomato (Solanum lycopersicum) remain largely unknown. Here, we report that SlSTOP1 is crucial for Al tolerance in tomato, as loss-of-function mutants of SlSTOP1 displayed hypersensitivity to Al stress. Aluminum stress had no effect on SlSTOP1 mRNA expression, but promoted accumulation of SlSTOP1 protein in the nucleus. Through integrated DNA affinity purification sequencing and RNA sequencing analysis, we identified 39 SlSTOP1-targeted Al-responsive genes, some of which are homologous to known Al resistance genes in other plant species, suggesting that these SlSTOP1-targeted genes play essential roles in Al resistance in tomato. Furthermore, using peak enrichment analysis of SlSTOP1-targeted sequences, we identified a cis-acting element bound by SlSTOP1 and validated this finding via dual-luciferase reporter and electrophoretic mobility shift assay (EMSA). Additionally, we demonstrated SlHAK5 is one of direct targets of SlSTOP1 and functionally characterized it in terms of Al stress tolerance. Compared with wild-type plants, Slhak5 mutants developed by CRISPR/Cas9 technology presented increased sensitivity to Al stress, which was associated with reduced citrate secretion from the roots. Together, our findings demonstrate that SlSTOP1 directly interacts with cis-acting elements located in the promoters of target genes involved in diverse pathways contributing to Al resistance in tomato.