Solanum Lycopersicum Plants Research Articles

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.

A LysR-type regulator influencing swimming motility, galactose utilization, and virulence in Ralstonia solanacearum GMI1000

BackgroundLysR-type transcriptional regulators (LTTRs) are one of the largest families of regulators in prokaryotic organism, which help the bacterium adapt to diverse conditions by controlling a wide array of regulons, encompassing genes responsible for nitrogen and carbon fixation, oxidative stress response, bacterial virulence, and the breakdown of diverse compounds. Ralstonia solanacearum strain GMI1000 possesses 80 LTTR genes, yet the precise roles and functional contributions of only three of these LTTRs have been conclusively established among the total. In this work, our group reveal a novel LTTR member LysR7 (RS_RS02375) that exerts multiple regulatory roles in motility, carbon metabolism and virulence.ResultsIn this investigation, an in-frame deletion mutant ΔlysR7 and a complemented strain CΔlysR7 were prepared. The mutant ΔlysR7 had increased swimming motility on semi-soft medium and showed a reduced replication rate in nutrient-rich medium and in planta. Moreover, ΔlysR7 was unable to grow on nutrient-limited medium, supplemented with galactose as a single carbon resource. RT-qPCR analysis and GUS activity detection indicated that the expression of lysR7 was induced in the presence of galactose. The mutant ΔlysR7 caused weaker wilt disease on either Solanum lycopersicum or Capsicum annuum plants compared to both wild type GMI1000 and CΔlysR7. Transcriptome analysis revealed that 12 upregulated and 8 downregulated differentially expressed genes (DEGs) in ΔlysR7 were restored in CΔlysR7 relative to wild type. In particular, the expression of hrpG, a key gene responsible for type III secretion system, was downregulated. KEGG analysis revealed that, except for lysR7 gene, the 19 DEGs were most enriched in microbial metabolism in diverse environments and metabolic pathways.ConclusionsThe data indicate that LysR7 regulates multiple processes in association with motility, galactose metabolism and virulence in R. solanacearum. The study offers valuable evidence to understand comprehensive regulatory mechanisms mediated by LTTR family members in R. solanacearum.Graphical

EVALUATING SOIL AMENDMENT EFFECTS ON TOMATO YIELD AND FRUIT QUALITY

This study investigates the impact of various soil treatments on key yield components of tomato (Solanum lycopersicum) plants, including fruit diameter, length, number per plant, and weight. Eight treatments were evaluated: BK+, MgSO4, CaPh, EcoTea, Pig Manure, Cow Manure, Combined Inorganic Fertilizer, and a Control. Comprehensive statistical analyses revealed significant differences in yield parameters across treatments. CaPh, MgSO4, and the Combined Inorganic fertilizer enhanced fruit production. EcoTea promoted larger tomato lengths, while Pig Dung increased weights. Mineral composition analyses showed distinct treatment effects on sodium, potassium, calcium, magnesium, and zinc levels. Nutrient profiling indicated varied impacts on moisture, protein, ash, fiber, fat, and carbohydrate contents. Strong correlations were observed between mineral and nutrient pairs, highlighting potential synergies and antagonisms. This research provides valuable insights into optimizing soil management practices for improved tomato yield, quality, and nutritional value, contributing to sustainable agricultural development.

Fungal pathogen: A game changer for insect herbivore in sequential attack on tomato

Plants have several means of coping with biotic stress, which involves physiological, cellular and molecular mechanisms. The interplay of two principal phytohormonal pathways, Jasmonic acid (JA) and Salicylic acid (SA) play a crucial role in transmitting stress-induced signals throughout the plant. However, the interplay of these hormonal pathways is not clear when plants encounter biotic agents that trigger antagonistic hormonal signals. To address this, we conducted biochemical and gene expression studies on tomato, Solanum lycopersicum plants, exposed to insect alone (IA), fungus alone (FA), or sequential dual stress with fungi followed by insect (FI) and insect followed by fungi (IF), with untreated control. We also assessed the performance of late-arriving conspecific herbivore on these plant sets. The total phenol, and non-tannin phenols content in IF and FI plants showed similar increase or decrease as FA and IA plants, respectively. Gene expression analysis revealed that JA-related genes (MYC2) were dominant in FI plants, while SA-related genes (PR1) were upregulated in IF plants. Moreover, late-arriving herbivores showed significantly decreased relative growth rate, efficiency of conversion of ingested food (ECI) and digested food (ECD) when feeding on FA and IF plants, indicating that sequential treatments substantially induce plant responses. However, herbivory did not affect the late-arriving conspecific herbivore. Thus, biochemical responses and hormonal interplay of the plant are influenced by both sequence as well as the duration of the biotic stress. Furthermore, while the late-arriving conspecific herbivore is negatively affected by the presence of a pathogen, it remains unaffected by previous herbivory.

Far-red light effects on plant photosynthesis: from short-term enhancements to long-term effects of artificial solar light

Abstract Background and Aims Long-term exposure over several days to Far-Red (FR) increases leaf expansion, while short-term exposure (minutes) may enhance the PSII operating efficiency (ϕPSII). The interaction between these responses at different time scales, and their impact on photosynthesis at whole-plant level is not well understood. Our study aimed to assess the effects of FR in an irradiance mimicking the spectrum of sunlight (referred to as artificial solar irradiance) both in the long and short-term, on whole-plant CO2 assimilation rates and in leaves at different positions in the plant. Methods Tomato (Solanum lycopersicum) plants were grown under artificial solar irradiance conditions with either a severely reduced or normal fraction of FR (SUN(FR-) vs. SUN). To elucidate the interplay between the growth light treatment and the short-term reduction of FR, we investigated this interaction at both the whole-plant and leaf level. At whole-plant level, CO2 assimilation rates were assessed under artificial solar irradiance with a normal and a reduced fraction of FR. At the leaf level, the effects of removal and presence of FR (0FR and 60FR) during transition from high to low light on CO2 assimilation rates and chlorophyll fluorescence were evaluated in upper and lower leaves. Key Results SUN(FR-) plants had lower leaf area, shorter stems, and darker leaves than SUN plants. While reducing FR during growth did not affect whole-plant photosynthesis under high light intensity, it had a negative impact at low light intensity. Short-term FR removal reduced both plant and leaf CO2 assimilation rates, but only at low light intensity and irrespective of the growth light treatment and leaf position. Interestingly, the kinetics of ϕPSII from high to low light were accelerated by 60FR, with a larger effect in lower leaves of SUN than in SUN(FR-) plants. Conclusions Growing plants with a reduced amount of FR light lowers whole-plant CO2 assimilation rates at low light intensity through reduced leaf area, despite maintaining similar leaf-level CO2 assimilation to leaves grown with a normal amount of FR. The short-term removal of FR brings about significant but marginal reductions in photosynthetic efficiency at the leaf level, regardless of the long-term growth light treatment.

The root-knot nematode effector MiEFF12 targets the host ER quality control system to suppress immune responses and allow parasitism.

Root-knot nematodes (RKNs) are microscopic parasitic worms able to infest the roots of thousands of plant species, causing massive crop yield losses worldwide. They evade the plant's immune system and manipulate plant cell physiology and metabolism to transform a few root cells into giant cells, which serve as feeding sites for the nematode. RKN parasitism is facilitated by the secretion in planta of effector molecules, mostly proteins that hijack host cellular processes. We describe here a conserved RKN-specific effector, effector 12 (EFF12), that is synthesized exclusively in the oesophageal glands of the nematode, and we demonstrate its function in parasitism. In the plant, MiEFF12 localizes to the endoplasmic reticulum (ER). A combination of RNA-sequencing analysis and immunity-suppression bioassays revealed the contribution of MiEFF12 to the modulation of host immunity. Yeast two-hybrid, split luciferase and co-immunoprecipitation approaches identified an essential component of the ER quality control system, the Solanum lycopersicum plant bap-like (PBL), and basic leucine zipper 60 (BZIP60) proteins as host targets of MiEFF12. Finally, silencing the PBL genes in Nicotiana benthamiana decreased susceptibility to Meloidogyne incognita infection. Our results suggest that EFF12 manipulates PBL function to modify plant immune responses to allow parasitism.

Surface modified ZnO NPs by betaine and proline build up tomato plants against drought stress and increase fruit nutritional quality

Drought stress is a serious challenge for global food production. Nanofertilizers and nanocomposites cope with such environmental stresses and also increase nutritional contents of fruits. An in vitro experiment was designed to use Zinc Oxide Nanoparticles (ZnO NPs) primed with Proline and Betaine (ZnOP and ZnOBt NPs) at 50 and 100 mg/kg soil against drought stress in Tomato (Solanum lycopersicum) plants. Plant morphological, biochemical, and fruit nutritional quality were accessed. Maximum plant height was observed under the treatment of ZnOP50 (1.09 m) and ZnO 100 (1.06 m). ZnOP and ZnOBt also improved the chlorophyll content up to 86% and 87.16%, respectively. Application of ZnOP NPs also demonstrated maximum tomato yield (204 g tomato/plant) followed by ZnO NPs and ZnOBt NPs. Nanocomposites decreased phenolics and flavonoids contents in drought stressed plants demonstrating the mitigation of oxidative stress. Nanofertilizer also increased the concentration of phenolics and flavonoids in fruits that increased the nutritional contents. Furthermore a significant accumulation of betaine, proline, and lycopene in fruits on nanocomposite treatment made it nutritional and healthy. Lycopene content increased up to 2.01% and 1.23% in presence of ZnOP50 and ZnOP100, respectively. These outcomes validate that drought stress in plant can be reduced by accumulation of different phytochemicals and quenching oxidative stress. The study deems that nano zinc carrying osmoregulators can greatly reduce the negative effects of drought stress and increase nutritional quality of tomato fruits.

Ralstonia solanacearum type III effector RipAF1 mediates plant resistance signaling by ADP-ribosylation of host FBN1.

Ralstonia solanacearum (Rso) causes destructive bacterial wilt across a broad range of host plants by delivering a repertoire of type III effectors. In the present study, we determined that the deletion of the type III effector RipAF1 resulted in increased virulence on Nicotiana benthamiana, Solanum lycopersicum, and Capsicum annuum plants. RipAF1 showed ADP-ribosylation activity in vivo and in vitro. Transient overexpression of RipAF1 suppressed jasmonic acid (JA) signaling and induced salicylic acid (SA) signaling. The ADP-ribosylation activity of RipAF1 was essential for JA and SA signaling mediation. Host fibrillin FBN1 was identified as a RipAF1-interactor that is ADP-ribosylated by RipAF1 directly. Most importantly, the ADP-ribosylation of conserved residues of FBN1 contributes to its localization to the plasma membrane and leads to the suppression of JA signaling and induction of SA signaling. We concluded that RipAF1 mediates antagonistic crosstalk between JA and SA signaling pathways by ADP-ribosylation of FBN1.

Green iron oxide nanoparticles and magnetic nanobiochar: enhancing tomato performance, phytochemicals, and root-knot nematode resistance

BackgroundGreen nanoparticles are considered to be an effective strategy for improving phytochemicals and raising productivity in soil infected by root-knot nematodes. This work aims to understand the characteristics of certain nanomaterials, including non-iron (nFe), green non-iron (GnFe), and green magnetic nanobiochar (GMnB), and the effect of adding them at 3 and 6 mg kg− 1 on phytochemicals and tomato (Solanum lycopersicum) plant growth in soils infected by root-knot nematodes.ResultsSpectroscopic characterization of nanomaterials showed that nFe, GnFe, and GMnB contained functional groups (e.g., Fe-O, S-H, C-H, OH, and C = C) and possessed a large surface area. Application of GMB at 6 mg kg− 1 was the most efficient treatment for increasing the phytochemicals of the tomato plant, with a rise of 123.2% in total phenolic, 194.7% in total flavonoids, 89.7% in total carbohydrate, 185.2% in total free amino acids, and 165.1% in total tannin compared to the untreated soil. Tomato plant growth and attributes increased with increasing levels of soil nano-amendment in this investigation. The addition of GnFe3 and GnFe6 increased the reduction of root galls of root-knot nematodes by 22.44% and 17.76% compared with nFe3 and nFe6, respectively. The inclusion of the examined soil nano-amendments increased phytochemicals and reduced the total number of root-knot nematodes on tomato plants at varying rates, which played a significant role in enhancing tomato growth.ConclusionsIn conclusion, treating tomato plants with GnFe or GMnB can be used as a promising green nanomaterial to eliminate root-knot nematodes and increase tomato yield in sandy clay loam soil.

Systemic defense induced by fatty acid compounds from marine macroalgae, Chaetomorpha antennina in tomato (Solanum lycopersicum) plants alters the susceptibility of the polyphagous agricultural pest, Spodoptera litura Fab

BackgroundSeaweeds contain a widespread range of fatty acids (FA), and several of them have potential bioactivity. FAs are dynamic members of all biota, as well as being acknowledged for their critical function in initiating phytohormone interactions and acting as important participants in many defense signalling pathways of the plant system. The current study looks at the defense-eliciting potentials of fatty acids from the green seaweed Chaetomorpha antennina (Bory) Kützing and their impact on the polyphagous insect pest Spodoptera litura (Fab).ResultsThe seaweed was detected with 19 fatty acids, with larger proportion of hexa and octadecanoic and linoleic acids. The algal fatty acid compounds (CFA) were successful in eliciting salicylic acid and phenolic compounds biosynthesis along with defense enzymes peroxidase (PO) and polyphenol oxidase (PPO). CFA enhanced the synthesis of defense enzymes, PO and PPO and phenols, post infestation with S. litura (> 50%) compared to control plants exposed to the pest. CFA was also effective in causing direct mortalities (96–98%) to the larvae (II-V instars). S. litura larvae exposed to elicited tomato plants displayed physiological incursions that extended larval-pupal duration to 26–28 days, preventing both morphogenetic transitions as well as affecting their morphology, that lead to the emergence of adults with malformed wings, legs. As a consequence, the fecundity was reduced by 60% affecting the reproductive performances of second-generation adults. The consumption rate (RCR) of larvae exposed to CFA was decreased by 84%, depicting feeding deterrence. These larvae were also observed with > 50% reduction in the levels of phosphatase enzyme secretion, bringing down larval growth rate from 0.58 to 0.34 mg/day. Histological analysis of exposed larvae displayed midgut cell disruption.ConclusionHence, the study finally confirms the elicitor potentials of fatty acid compounds from C. antennina, by inducing natural systemic defenses. This investigation unlocks novel forecasts besides delivering an unconventional method for crop protection to moderate or interchange the solicitation of chemical pesticides.Graphical

Genome-Wide Characterization and Functional Validation of the ACS Gene Family in the Chestnut Reveals Its Regulatory Role in Ovule Development.

Ovule abortion significantly contributes to a reduction in chestnut yield. Therefore, an examination of the mechanisms underlying ovule abortion is crucial for increasing chestnut yield. In our previous study, we conducted a comprehensive multiomic analysis of fertile and abortive ovules and found that ACS genes in chestnuts (CmACS) play a crucial role in ovule development. Therefore, to further study the function of ACS genes, a total of seven CmACS members were identified, their gene structures, conserved structural domains, evolutionary trees, chromosomal localization, and promoter cis-acting elements were analyzed, and their subcellular localization was predicted and verified. The spatiotemporal specificity of the expression of the seven CmACS genes was confirmed via qRT-PCR analysis. Notably, CmACS7 was exclusively expressed in the floral organs, and its expression peaked during fertilization and decreased after fertilization. The ACC levels remained consistently greater in fertile ovules than in abortive ovules. The ACSase activity of CmACS7 was identified using the genetic transformation of chestnut healing tissue. Micro Solanum lycopersicum plants overexpressing CmACS7 had a significantly greater rate of seed failure than did wild-type plants. Our results suggest that ovule fertilization activates CmACS7 and increases ACC levels, whereas an overexpression of CmACS7 leads to an increase in ACC content in the ovule prior to fertilization, which can lead to abortion. In conclusion, the present study demonstrated that chestnut ovule abortion is caused by poor fertilization and not by nutritional competition. Optimization of the pollination and fertilization of female flowers is essential for increasing chestnut yield and reducing ovule abortion.

First report of the cotton mealybug, Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae) in Greece

AbstractPhenacoccus solenopsis Tinsley, 1898 (Hemiptera: Pseudococcidae), commonly known as the cotton mealybug or solenopsis mealybug, is a highly polyphagous species. This paper provides the first report of this species in Greece. It was detected in high numbers on tomato (Solanum lycopersicum) plants cultivated in a greenhouse in the region of Mirtos, close to the city of Ierapetra in the Southeast part of the island of Crete. The species identification was carried out using morphological and molecular analyses. The fact that P. solenopsis can be transferred easily via trade of live plant material, in combination with its ability to affect many different hosts causing severe damage, constitutes an increasing threat to Greek cultivation and especially to horticultural and vegetable crops. Additional surveys should be conducted to investigate the species distribution in Greece.

Molecular characterization and pathogenicity of a novel monopartite geminivirus infecting tobacco in China

The occurrence of geminiviruses causes significant economic losses in many economically important crops. In this study, a novel geminivirus isolated from tobacco in Sichuan province of China, named tomato leaf curl Chuxiong virus (TLCCxV), was characterized by small RNA-based deep sequencing. The full-length of TLCCxV genome was determined to be 2744 nucleotides (nt) encoding six open reading frames. Phylogenetic and genome-wide pairwise identity analysis revealed that TLCCxV shared less than 91% identities with reported geminiviruses. A TLCCxV infectious clone was constructed and successfully infected Nicotiana benthamiana, N. tabacum, N. glutinosa, Solanum lycopersicum and Petunia hybrida plants. Furthermore, expression of the V2, C1 and C4 proteins through a potato virus X vector caused severe chlorosis or necrosis symptom in N. benthamiana. Taken together, we identified a new geminivirus in tobacco plants, and found that V2, C1 and C4 contribute to symptom development.

Metabolic crosstalk between hydroxylated monoterpenes and salicylic acid in tomato defense response against bacteria.

Hydroxylated monoterpenes (HMTPs) are differentially emitted by tomato (Solanum lycopersicum) plants resisting bacterial infection. We have studied the defensive role of these volatiles in the tomato response to bacteria, whose main entrance are through stomatal apertures. Treatments with some HMTPs resulted in stomatal closure and pathogenesis-related protein 1 (PR1) induction. Particularly, α-terpineol induced stomatal closure in a salicylic acid (SA) and abscisic acid-independent manner and conferred resistance to bacteria. Interestingly, transgenic tomato plants overexpressing or silencing the monoterpene synthase MTS1, which displayed alterations in the emission of HMTPs, exhibited changes in the stomatal aperture but not in plant resistance. Measures of both 2-C-methyl-D-erythritol-2,4-cyclopyrophosphate (MEcPP) and SA levels revealed competition for MEcPP by the methylerythritol phosphate (MEP) pathway and SA biosynthesis activation, thus explaining the absence of resistance in transgenic plants. These results were confirmed by chemical inhibition of the MEP pathway, which alters MEcPP levels. Treatments with BTH, a SA functional analogue, conferred enhanced resistance to transgenic tomato plants overexpressing MTS1. Additionally, these MTS1 overexpressors induced PR1 gene expression and stomatal closure in neighbouring plants. Our results confirm the role of HMTPs in both intra and inter-plant immune signalling and reveal a metabolic crosstalk between the MEP and SA pathways in tomato plants.

Transcriptomic characterization of the response to a microalgae extract in Arabidopsis thaliana and Solanum lycopersicum.

The steady world population growth and the current climate emergency crisis demand the development of sustainable methods to increase crop performance and resilience to the abiotic and biotic stresses produced by global warming. Microalgal extracts are being established as sustainable sources to produce compounds that improve agricultural yield, concurrently contributing during their production process to atmospheric CO2 abatement through the photosynthetic activity of microalgae. In the present study, we characterize the transcriptomic response in the model plant Arabidopsis thaliana and the plant of horticultural interest Solanum lycopersicum to the foliar application of a microalgae-based commercial preparation LRM™ (AlgaEnergy, Madrid, Spain). The foliar spray of LRM™ has a substantial effect over both transcriptomes potentially mediated by various compounds within LRM™, including its phytohormone content, activating systemic acquired resistance, possibly mediated by salicylic acid biosynthetic processes, and drought/heat acclimatization, induced by stomatal control and wax accumulation during cuticle development. Specifically, the agronomic improvements observed in treated S. lycopersicum (tomato) plants include an increase in the number of fruits, an acceleration in flowering time and the provision of higher drought resistance. The effect of LRM™ foliar spray in juvenile and adult plants was similar, producing a fast response detectable 2 h from its application that was also maintained 24 h later. The present study improves our knowledge on the transcriptomic effect of a novel microalgal extract on crops and provides the first step towards a full understanding of the yield and resistance improvement of crops. © 2024 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Distinct tomato yellow leaf curl Chuxiong virus isolated from whiteflies and plants in China and its symptom determinant and suppressor of post-transcriptional gene silencing

A begomovirus isolated from whiteflies (Bemisia tabaci) and tomato, sweet potato in China was found to be representative of a distinct begomovirus species, for which the name tomato yellow leaf curl Chuxiong virus (TYLCCxV) is proposed. The results of genomic identification and sequence comparison showed that TYLCCxV shares the highest complete nucleotide sequence identity (88.3%) with croton yellow vein mosaic virus (CroYVMV), and may have originated from the recombination between synedrella leaf curl virus (SyLCV) and squash leaf curl Yunnan virus (SLCuYV). Agrobacterium-mediated inoculation showed that TYLCCxV is highly infectious for a range of plant species, producing upward leaf curling, leaf crumpling, chlorosis, distortion, and stunt symptoms in Solanum lycopersicum plants. The results of Southern blot indicated that TYLCCxV is capable of efficiently replicating two heterologous betasatellites. The inoculation of PVX::C4 on Nicotiana benthamiana induced upward leaf curling and stem elongation symptoms, suggesting that TYLCCxV C4 functions as a symptom determinant. TYLCCxV V2 is an important virulence factor that induces downward leaf curling symptoms, elicits systemic necrosis, and suppresses local and systemic GFP silencing in co-agroinfiltrated N. benthamiana and transgenic 16c plants. Considering the multifunctional virulence proteins V2 and C4, the possibility of TYLCCxV causing devastating epidemics on tomato in China is discussed.

Phosphorylation of sugar transporter TST2 by protein kinase CPK27 enhances drought tolerance in tomato.

Drought is a major environmental stress threatening plant growth and productivity. Calcium-dependent protein kinases (CPKs) are plant-specific Ca2+ sensors with multifaceted roles in signaling drought responses. Nonetheless, the mechanisms underpinning how CPKs transmit downstream drought signaling remain unresolved. Through genetic investigations, our study unveiled that knocking out CPK27 reduced drought tolerance in tomato (Solanum lycopersicum) plants and impaired abscisic acid (ABA)-orchestrated plant response to drought stress. Proteomics and phosphoproteomics revealed that CPK27-dependent drought-induced proteins were highly associated with the sugar metabolism pathway, which was further verified by reduced soluble sugar content in the cpk27 mutant under drought conditions. Using protein-protein interaction assays and phosphorylation assessments, we demonstrated that CPK27 directly interacted with and phosphorylated tonoplast sugar transporter 2 (TST2), promoting intercellular soluble sugar accumulation during drought stress. Furthermore, Ca2+ and ABA enhanced CPK27-mediated interaction and phosphorylation of TST2, thus revealing a role of TST2 in tomato plant drought tolerance. These findings extend the toolbox of potential interventions for enhancing plant drought stress tolerance and provide a target to improve drought tolerance by manipulating CPK27-mediated soluble sugar accumulation for rendering drought tolerance in a changing climate.

Tomato plant growth promotion and drought tolerance conferred by three arbuscular mycorrhizal fungi is mediated by lipid metabolism

Arbuscular mycorrhizal fungi (AMF) can promote plant growth and enhance plant drought tolerance with varying effect size among different fungal species. However, the linkage between the variation and the lipid metabolism, which is exclusively derived from plants, has been little explored thus far. Here, we established AM symbiosis between tomato (Solanum lycopersicum) plants and three AMF species (Rhizophagus intraradices, Funneliformis mosseae, Rhizophagus irregularis) under well watered (WW) or drought stressed (DS) conditions in pot experiment. The plant biomass, chlorophyll fluorescence Fv/Fm, shoot P content and mycorrhizal colonization were determined. Meanwhile, fatty acid (FA) profiles and relative expression of genes encoding for nutrition exchange (SlPT4, SlPT5, RAM2, STR/STR2) in roots were also monitored. DS significantly decreased plant biomass while AMF significantly increased it, with three fungal species varying in their growth promoting capacity and drought tolerance capacity. The growth promoting effect of R. irregularis was lower than those of R. intraradices and F. mosseae, and was associated with higher mycorrhizal colonization and more consumption of lipids. However, the drought tolerance capacity of R. irregularis was greater than those of R. intraradices and F. mosseae, and was associated with less decrease in mycorrhizal colonization and lipid content. We also found that AMF mediated plant drought tolerance via regulating both AM specific FAs and non-AM specific FAs in a complementary manner. These data suggest that lipid metabolism in AM plays a crucial role in plant drought tolerance mediated by AMF.

Antiherpetic Activity of a Root Exudate from Solanum lycopersicum.

The rise of drug resistance to antivirals poses a significant global concern for public health; therefore, there is a pressing need to identify novel compounds that can effectively counteract strains resistant to current antiviral treatments. In light of this, researchers have been exploring new approaches, including the investigation of natural compounds as alternative sources for developing potent antiviral therapies. Thus, this work aimed to evaluate the antiviral properties of the organic-soluble fraction of a root exudate derived from the tomato plant Solanum lycopersicum in the context of herpesvirus infections. Our findings demonstrated that a root exudate from Solanum lycopersicum exhibits remarkable efficacy against prominent members of the family Herpesviridae, specifically herpes simplex virus type 1 (HSV-1) (EC50 25.57 µg/mL, SI > 15.64) and human cytomegalovirus (HCMV) (EC50 9.17 µg/mL, SI 32.28) by inhibiting a molecular event during the herpesvirus replication phase. Moreover, the phytochemical fingerprint of the Solanum lycopersicum root exudate was characterized through mass spectrometry. Overall, these data have unveiled a novel natural product with antiherpetic activity, presenting a promising and valuable alternative to existing drugs.