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The main objective of this study was to estimate and compare substitution matrixes of nucleotide frequencies for Tomato leaf curl New Delhi virus (ToLCNDV) with recently identified begomoviral isolates from two medicinal false daisy (Eclipta prostrata) and tomato (Solanum lycopersicum) plants. The ToLCNDV has become a significant limitation to vegetables production in many countries. A polymerase chain reaction was conducted to conserve the existence of begomoviral infection. The acquired amplicon was amplified using primers appropriate to the sequence in order to retrieve the full genome. The sequence analysis has confirmed the presence of ToLCNDV in symptomatic plants. The complete genome sequence having a 2.6–2.7 kb entire genome of ToLCNDV was obtained. An investigation of the phylogenetic and evolutionary history has verified the connection between this virus and other closely related viruses. The available nucleotide frequencies of codon regions (A, T/U, C, G) with newly isolates revealed 20–28% substitution matrixes. There was a minimal difference of nucleotide frequencies' with already submitted database of this virus. Substitution matrixes, which quantify the probability of nucleotide substitutions evolving over a period of time, offer valuable information about mutation patterns and the forces driving evolution. This comparative analysis enhanced the comprehension of the genetic diversity of ToLCNDV and its possible consequences on medicinal plants. It also assisted in the formulation of efficient control measures and the preservation of begomoviruses in medicinal plant biodiversity. The information presented here is highly valuable for understanding the ToLCNDV biology and epidemiology, and it would also assist in disease management in the future. [ABSTRACT FROM AUTHOR]

Background: The polyphagous notorious pest, black cutworm, Agrotis ipsilon (Hufnagel) (Lepidoptera: Noctuidae), cause significant production losses due to its distinctive feeding and hiding behavior, making it particularly challenging to control it with conventional methods. Therefore, sustainable agriculture demands more effective and environmentally safe pest control solutions. This study aimed to investigate the toxicity of two insecticide alternatives, the entomopathogenic fungus (EPF) Beauveria bassiana and Solanum lycopersicum extract (Tomato plant crude extract, TPCE), using two bioassay methods: the poisoned bait method and the leaf dipping method. In addition, the impact of these biological tools on larval development and protein profiles was evaluated. Results: The bait application of both tested materials exhibited higher toxicity than the leaf dipping method, as indicated by the toxicity index. The LC50 values for B. bassiana were 1.6 × 10⁸ and 1.8 × 10⁶ conidia ml−1 using the leaf dipping method and poisoned baits method, respectively. For TPCE, the LC50 values were 4.35 and 1.51 mg ml−1 for the same methods, respectively. In addition, sublethal concentrations of both materials altered the larval and pupal durations. B. bassiana significantly reduced the concentration of larval hemolymph protein. A maximum of 12 protein bands in the control sample, with molecular weights (Mw) ranging between 35 and 120 kDa, were detected by sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS–PAGE). In B. bassiana-treated larvae, ten bands were detected with Mw ranging from 35 to 120 kDa. At least seven bands were detected in TPCE-treated larvae, with Mw ranging from 35 to 97 kDa. Conclusions: The findings of this study can be integrated into management programs for A. ipsilon. In addition, the availability of B. bassiana and TPCE in Egypt and their cost-effectiveness as insecticide alternatives support their use in the management programs of this critical pest. These methods are particularly effective when applied in bait form. [ABSTRACT FROM AUTHOR]

In this work, the authors investigated the possibility of modifying the fatty acid (FA) composition of tomato leaves (Solanum lycopersicum L.) by introducing into its genome the gene of the cyanobacterial Δ9 acyl-lipid desaturase (Synechococcus vulcanus C.). To obtain transgenic tomato plants expressing cyanobacterial desaturase (desC) and to evaluate the effect of this desaturase on the FA composition of total lipids, vectors carrying the gene desC were constructed. The gene sequence was fused with leader sequences that ensure localization of the protein product in chloroplasts, endoplasmic reticulum (ER), or cytoplasmic membrane. The resulting vectors were used to transform the A. tumefaciens AGL0 strain for subsequent agrobacterium-mediated transformation of tomato plants. FA analysis of leaves showed that, when desC is localized in the cytoplasmic membrane or ER membrane, an increase in the content of C16:1 and C16:2 fatty acids is observed for some lines. For these lines, an increase in the relative representation of the transcript desC compared to transgenic lines that did not show changes in FA composition is shown. The obtained data can be used to develop strategies for targeted modification of the fatty acid composition of tomatoes. [ABSTRACT FROM AUTHOR]

Late blight (LB), caused by oomycete Phytophthora infestans, is one of the most destructive diseases of the cultivated tomato, Solanum lycopersicum. Since new and aggressive clonal lineages of P. infestans, many of which overcoming formerly effective fungicides or host resistance genes, have continued to emerge, it is crucial to identify, characterize, and utilize new sources of host resistance in tomato breeding. A recent screening of tomato germplasm identified Solanum pimpinellifolium accession PI 224710 with very strong resistance to several current P. infestans clonal lineages. The present study aimed to identify and characterize QTLs associated with LB resistance in PI 224710. Disease screening of a large F2 population (n = 1721), derived from a cross between PI 224710 and LB-susceptible tomato breeding line Fla. 8059, followed by F3 progeny testing, resulted in the identification of 43 highly-resistant and 27 highly-susceptible F2 individuals. A selective genotyping approach, using 469 non-identical SNP markers, resulted in the construction of a genetic linkage map and identification of three LB-resistance QTLs on chromosomes 6, 9 and 10 of PI 224710. A comparison of the QTLs genomic locations with the tomato physical map resulted in the identification of several candidate genes, which might be underpinning the LB-resistance QTLs in PI 224710. The identified markers associated with the LB-resistance QTLs can be utilized in breeding programs to transfer resistance from PI 224710 into tomato breeding lines and hybrid cultivars via marker-assisted breeding; they also can be used to develop near-isogenic lines for fine mapping of the QTLs. [ABSTRACT FROM AUTHOR]

The circadian dynamics of the expression of key genes of carotenoid metabolism (PSY2, LCYE, CrtRB1, and NCED1) in the photosynthetic tissue of tomato Solanum lycopersicum L. (cultivar Korneevsky) plants was characterized. An in silico analysis of the gene expression pattern was carried out and a high level of their transcripts was detected in the leaf tissue. qRT-PCR analysis of gene expression was performed at six time points during the day and showed the highest levels of PSY2, LCYE, and NCED1 transcripts in the second half of the light phase and CrtRB1 at the end of the dark phase. The content and composition of carotenoids in leaf tissue in the middle of the day was determined; it was shown that the leaf accumulates 1.5 times more compounds of the ɛ/β-branch of carotenoid biosynthesis pathway than compounds of the β/β-branch. [ABSTRACT FROM AUTHOR]

The genus Streptomyces (Actinomycetota) is known to contain strains that are very prospective biocontrol agents, but limited research focused on their ability to enhance plant defence after foliar treatments, thus posing technical limits to their potential use. In this study, the Streptomyces sp. DLS2013 was able to epiphytically colonise tomato leaves under controlled conditions. Following plant colonisation by DLS2013, RNA-Seq analysis was conducted on tomato leaves for up to 24 h after treatment to investigate possible changes in the transcriptome and to identify new putative marker genes associated with enhanced plant disease resistance. RNA-Seq data suggested that a DLS2013 treatment triggers plant defence by up-regulating, in a time course manner, defence pathways dependent on salicylic and jasmonic acids, and promoting the synthesis of antimicrobial metabolites, like polyamines (i.e. putrescine and spermidine) and phenolic compounds (i.e. stilbenoids and phenylpropanoids). Conversely, the down-regulation of genes involved in photosynthesis metabolic pathways was highlighted, as a “compensation marker” for the triggered defence response. Additionally, the ability of DLS2013 to elicit resistance in tomato against Pseudomonas syringae pv. tomato was investigated by assessing the transcription kinetics of six genes associated with distinct defence response pathways, highlighting the key role of PR-1 and JAZ 25 repressor in the tomato resistance to bacterial speck. Finally, our results propose JAZ 25 gene as additional benchmark for defence priming. [ABSTRACT FROM AUTHOR]

Leveillula taurica has until recently been believed to be the causal pathogen of powdery mildew of tomatoes in Mauritius. However, in the year 2022, another powdery mildew species was detected on tomatoes under culture in various tomato growing localities of the island. Based on morphological comparison and molecular analysis, its identity was confirmed as Erysiphe neolycopersici (anam. Pseudoidium neolycopersici). This species has a worldwide distribution causing severe epidemics mainly on greenhouse tomatoes. There is evidence of the rapid spread of this pathogen during 2022–2023 causing serious infection of all tomato cultivars in greenhouse culture in Mauritius. The origin of these infections and its epidemiological consequences are discussed. [ABSTRACT FROM AUTHOR]

This study employed two prevalent plastic products - straws and microfiber as microplastics (MPs) to elucidate their largely unexplored effects on soil's properties and the growth of the tomato plant (Solanum lycopersicum L.). For this experiment, a completely randomized design (CRD) was adopted where, straw - polypropylene (PP), microfiber - polyester (PES) + polyamide (PA), and their combinations (PP + PES + PA) were mixed with soil using different concentrations – 0% (control), 0.4%, 1%, and 2% (treatments) and kept for 45 days at room temperature. The findings demonstrated that incorporating 2% mixed MPs in soil significantly decreased bulk density and electrical conductivity 7.29% and 67.3%, respectively, while soil pH increased 17.84% in cultures containing 1% microfiber. Maximum water holding capacity (MWHC), soil organic carbon (SOC), and soil organic matter (SOM) showed varied responses based on MPs type and concentration. Specifically, MWHC increased 16.4% with 2% microfiber but declined 13.3% with 0.4% straw. The highest decreased (30.65%) in SOC and SOM were evident in cultures with 1% microfiber whereas increased 9.68% and 8.33% in cultures with 0.4% straw. In terms of the growth traits of S. lycopersicum, substantial reductions in plant height (56.37%), leaf number (54.37%), and girth diameter (56.43%) were observed in 2% straw containing cultures. Although no plant mortality was noted, the most pronounced reductions in leaf area (62.44%) and total plant biomass (68.16%) occurred in 2% microfiber cultures. Therefore, the ramifications of these findings may contribute to a deeper comprehension of the mechanisms and effects of MPs on soil properties and above-ground plant growth. [ABSTRACT FROM AUTHOR]

Tomato Solanum lycopersicum is an important economic fruit, and widely consumed for its high nutritional quality. Our previous study found that AtERF022, a member of Arabidopsisthaliana ethylene response factors (ERFs) group III, acted a vital role in Arabidopsis growth and development. However, whether or how endogenous AtERF022 confers tomato fruit quality is still elusive. To explore the role of AtERF022 gene in tomato fruit ripening and nutritional quality, we generated AtERF022-overexpressing tomato line by transgenic and plant tissue culture technology. Our results showed that the higher expression of AtERF022 was found in tomato flowers and fruits, especially in orange ripening stage of fruits. Compared to wild-type, AtERF022-overexpressing tomato exhibited morphological growth advantages and elevated fruit ripening and nutritional quality. Further experiments and transcriptome sequencing showed that overexpression of AtERF022 enhanced the expression of genes involved in ethylene biosynthesis, cell wall metabolism, chlorophyll degradation, carotenoids and flavonoids biosynthesis, and thereby promoting fruit ripening, β-carotene, flavonoids, vitamin C and total phenols accumulation. Together, our results provide genetic evidence that AtERF022 regulates tomato fruit ripening and nutritional quality. [ABSTRACT FROM AUTHOR]

Biostimulants such as seaweed extracts are widely used to stimulate plant growth and crop productivity under optimal or stressful conditions, constituting a sustainable strategy to mitigate the impacts of abiotic stress on plant performance. In this study, a growth experiment was conducted to evaluate the effects of an aqueous extract from the seaweed Padina gymnospora on the physiological, biochemical, and molecular characteristics of Solanum lycopersicum under salt stress. The experiment included four treatments: 1) control plants, 2) plants irrigated with 300 mM NaCl solution, 3) plants treated with the P. gymnospora extract, and 4) plants treated with the P. gymnospora extract and irrigated with 300 mM NaCl solution. Salt stress increased the activity of antioxidant enzymes (catalase and superoxide dismutase) and resulted in the overaccumulation of the osmolyte proline and flavonoids while enhancing photosynthetic performance and chlorophyll content. In addition, treatment with P. gymnospora extract increased total reducing sugars and phenols in salt-stressed plants, which was correlated with DPPH and ABTS antioxidant activity. The induction of stress-responsive genes, such as SlHB7, SlSOD1, SlRD29, and SlHKT, appears to be a major factor modulating the responses to P. gymnospora extract application in tomato plants. The results of this study demonstrate that the application of P. gymnospora to tomato plants attenuated the damage caused by salt stress. It is essential to continue studying the potential of seaweed extracts to mitigate stress in plants, given the promising agricultural applications of these novel biostimulants. [ABSTRACT FROM AUTHOR]

Phenylpropanoids, a class of specialized metabolites, play crucial roles in plant growth and stress adaptation and include diverse phenolic compounds such as flavonoids. Phenylalanine ammonia-lyase (PAL) and chalcone synthase (CHS) are essential enzymes functioning at the entry points of general phenylpropanoid biosynthesis and flavonoid biosynthesis, respectively. In Arabidopsis, PAL and CHS are turned over through ubiquitination-dependent proteasomal degradation. Specific kelch domain-containing F-Box (KFB) proteins as components of ubiquitin E3 ligase directly interact with PAL or CHS, leading to polyubiquitinated PAL and CHS, which in turn influences phenylpropanoid and flavonoid production. Although phenylpropanoids are vital for tomato nutritional value and stress responses, the post-translational regulation of PAL and CHS in tomato remains unknown. We identified 31 putative KFB-encoding genes in the tomato genome. Our homology analysis and phylogenetic study predicted four PAL-interacting SlKFBs, while SlKFB18 was identified as the sole candidate for the CHS-interacting KFB. Consistent with their homolog function, the predicted four PAL-interacting SlKFBs function in PAL degradation. Surprisingly, SlKFB18 did not interact with tomato CHS and the overexpression or knocking out of SlKFB18 did not affect phenylpropanoid contents in tomato transgenic lines, suggesting its irreverence with flavonoid metabolism. Our study successfully discovered the post-translational regulatory machinery of PALs in tomato while highlighting the limitation of relying solely on a homology-based approach to predict interacting partners of F-box proteins.Key message: Despite its highest sequence homology with Arabidopsis CHS-interacting KFB among 31 tomato KFBs, SlKFB18 does not function in CHS degradation, while predicted PAL-interacting SlKFBs function in PAL degradation in tomato. [ABSTRACT FROM AUTHOR]

Key message: Whole-genome QTL mining and meta-analysis in tomato for resistance to bacterial and fungal diseases identified 73 meta-QTL regions with significantly refined/reduced confidence intervals. Tomato production is affected by a range of biotic stressors, causing yield losses and quality reductions. While sources of genetic resistance to many tomato diseases have been identified and characterized, stability of the resistance genes or quantitative trait loci (QTLs) across the resources has not been determined. Here, we examined 491 QTLs previously reported for resistance to tomato diseases in 40 independent studies and 54 unique mapping populations. We identified 29 meta-QTLs (MQTLs) for resistance to bacterial pathogens and 44 MQTLs for resistance to fungal pathogens, and were able to reduce the average confidence interval (CI) of the QTLs by 4.1-fold and 6.7-fold, respectively, compared to the average CI of the original QTLs. The corresponding physical length of the CIs of MQTLs ranged from 56 kb to 6.37 Mb, with a median of 921 kb, of which 27% had a CI lower than 500 kb and 53% had a CI lower than 1 Mb. Comparison of defense responses between tomato and Arabidopsis highlighted 73 orthologous genes in the MQTL regions, which were putatively determined to be involved in defense against bacterial and fungal diseases. Intriguingly, multiple genes were identified in some MQTL regions that are implicated in plant defense responses, including PR-P2, NDR1, PDF1.2, Pip1, SNI1, PTI5, NSL1, DND1, CAD1, SlACO, DAD1, SlPAL, Ph-3, EDS5/SID1, CHI-B/PR-3, Ph-5, ETR1, WRKY29, and WRKY25. Further, we identified a number of candidate resistance genes in the MQTL regions that can be useful for both marker/gene-assisted breeding as well as cloning and genetic transformation. [ABSTRACT FROM AUTHOR]

Elicitors are considered sustainable alternatives for the management of phytopathogenic viruses. The aim of the present study was to evaluate the effectiveness of nine elicitors on morphology, yield, and fruit quality of tomato plants inoculated with the Tomato brown rugose fruit virus (ToBRFV-Tobamovirus/Virgaviridae), Pepino mosaic virus (PepMV-Potexvirus/Alphaflexiviridae), and mixed infection (ToBRFV + PepMV). The experiment was set up under a completely randomized design with six replicates. Ten days after transplanting, virus inoculation was done mechanically in all the treatments, except the negative controls. Three morphological, four yield, and seven fruit quality variables were evaluated. Virablock® 3G50 increased yield by more than 44% compared with the positive control in plants inoculated with ToBRFV, PepMV, and the mixed infection, while Supermagro cell extract and enhanced Supermagro increased yield in plants inoculated with ToBRFV and the mixed infection by more than 82% and 34%, respectively. Virablock® 3G50 and an ethanolic extract of Arracacia bracteata showed the highest values in fruit quality variables. [ABSTRACT FROM AUTHOR]

The South American tomato pinworm Tuta absoluta (Meyrick, 1971) (Lepidoptera: Gelechiidae) causes economic losses in solanaceous crops. Chemical pesticides are the main management methods used against this pest, which causes the emergence of resistances in pest populations. Therefore, it is crucial to identify and develop new molecules showing toxicity to T. absoluta while being less harmful to the environment, to beneficial organisms and to human health. The objective of this study was to evaluate the lethal and sublethal effects of three essential oils (EOs) of Cinnamomum spp. (Lauraceae) against T. absoluta. We evaluated the effects of the EOs during the life cycle of the pest using an age-stage, two-sex life table. We assessed leaf consumption by T. absoluta treated with EOs or the main compounds found in EOs, cinnamaldehyde and linalool. Additionally, we investigated the toxicity of the EOs to the predator Macrolophus basicornis (Stal, 1860) (Hemiptera: Miridae). Our findings indicate that EOs significantly decreased the duration of all life cycle stages of T. absoluta in 5 days, as well as fecundity by 55%, oviposition period by 2 days and viability of second generation eggs by 50%. Cinnamaldehyde and linalool resulted in 83.3% and 86.7% mortality, respectively, of T. absoluta larvae, showing that these major EO compound significantly contribute to EO insecticidal activity. However, all three EOs caused between 43 and 53% of mortality to M. basicornis. Although Cinnamomum essential oils show great insecticidal potential for T. absoluta, they may not be compatible with other IPM tools such as the use of biocontrol agents when used at the LD50 for T. absoluta. [ABSTRACT FROM AUTHOR]

Plants and microorganisms establish beneficial associations that can improve their development and growth. Recently, it has been demonstrated that bacteria isolated from the skin of amphibians can contribute to plant growth and defense. However, the molecular mechanisms involved in the beneficial effect for the host are still unclear. In this work, we explored whether bacteria isolated from three tropical frogs species can contribute to plant growth. After a wide screening, we identified three bacterial strains with high biostimulant potential, capable of modifying the root structure of Arabidopsis thaliana plants. In addition, applying individual bacterial cultures to Solanum lycopersicum plants induced an increase in their growth. To understand the effect that these microorganisms have over the host plant, we analysed the transcriptomic profile of A. thaliana during the interaction with the C32I bacterium, demonstrating that the presence of the bacteria elicits a transcriptional response associated to plant hormone biosynthesis. Our results show that amphibian skin bacteria can function as biostimulants to improve agricultural crops growth and development by modifying the plant transcriptomic responses. [ABSTRACT FROM AUTHOR]

Biostimulants are heterogeneous products designed to support plant development and to improve the yield and quality of crops. Here, we focused on the effects of triacontanol, a promising biostimulant found in cuticle waxes, on tomato growth and productivity. We examined various phenological traits related to vegetative growth, flowering and fruit yield, the metabolic profile of fruits, and the response of triacontanol-treated plants to salt stress. Additionally, a proteomic analysis was conducted to clarify the molecular mechanisms underlying triacontanol action. Triacontanol application induced advanced and increased blooming without affecting plant growth. Biochemical analyses of fruits showed minimal changes in nutritional properties. The treatment also increased the germination rate of seeds by altering hormone homeostasis and reduced salt stress-induced damage. Proteomics analysis of leaves revealed that triacontanol increased the abundance of proteins related to development and abiotic stress, while down-regulating proteins involved in biotic stress resistance. The proteome of the fruits was not significantly affected by triacontanol, confirming that biostimulation did not alter the nutritional properties of fruits. Overall, our findings provide evidence of the effects of triacontanol on growth, development, and stress tolerance, shedding light on its mechanism of action and providing new insights into its potential in agricultural practices. [ABSTRACT FROM AUTHOR]

The use of bio-nanotechnology in agriculture—such as the biological applications of metal oxide nanoparticles (NPs)—greatly improves crop yield and quality under different abiotic stress factors including soil metal contamination. Here, we explore the effectiveness of zinc oxide (ZnO)-NPs (0, 50 mg/L) foliar spraying to ameliorate the detrimental effects of cadmium (Cd) on the water transport and nitrogen metabolism in tomato (Solanum lycopersicum Mill. cv. Chibli F1) plants grown on a Cd-supplied (CdCl2; 0, 10, 40 μM) Hoagland nutrient solution. The results depicted that the individually studied factors (ZnO-NPs and Cd) had a significant impact on all the physiological parameters analyzed. Independently to the Cd concentration, ZnO-NPs-sprayed plants showed significantly higher dry weight (DW) in both leaves and roots compared to the non-sprayed ones, which was in consonance with higher and lower levels of Zn2+ and Cd2+ ions, respectively, in these organs. Interestingly, ZnO-NPs spraying improved water status in all Cd-treated plants as evidenced by the increase in root hydraulic conductance (L0), apoplastic water pathway percentage, and leaf and root relative water content (RWC), compared to the non-sprayed plants. This improved water balance was associated with a significant accumulation of osmoprotectant osmolytes, such as proline and soluble sugars in the plant organs, reducing electrolyte leakage (EL), and osmotic potential (ψπ). Also, ZnO-NPs spraying significantly improved NO3− and NH4+ assimilation in the leaf and root tissues of all Cd-treated plants, leading to a reduction in NH4+ toxicity. Our findings point out new insights into how ZnO-NPs affect water transport and nitrogen metabolism in Cd-stressed plants and support their use to improve crop resilience against Cd-contaminated soils. [ABSTRACT FROM AUTHOR]

Two standard area diagrams (SADs) were developed to quantify the severity of tomato early blight (EB), caused by Alternaria solani, on leaves and leaflets. The SADs were composed by sets of images with distinct EB severity for leaflets (0–40%) and leaves (0-46.4%). To validate the diagrams, 13 evaluators with no experience in quantifying the plant disease severity estimated EB severity by using a 50-image sample of tomato leaves and leaflets, first without SADs and then using the proposed SADs. The data were submitted to regression analysis and Lin's concordance correlation coefficient, and the accuracy, precision, repeatability, and reproducibility of the estimates for EB severity were assessed. Based on the parameters of Lin's coefficients and intraclass correlations, EB severity estimates were consistent and more reliable using SADs, improving evaluators' performance. The diagrams proposed in this study improved the quantification of EB severity performed by 13 evaluators, increasing the accuracy, precision, and reliability of the estimates. Therefore, the proposed diagrams can be used in further studies on the epidemiology, resistance, and management strategies of this pathosystem. [ABSTRACT FROM AUTHOR]

Background and aims: Food production is threatened by direct climate change effects including drought. Indirect effects, including changes in plant-pathogen dynamics and increased susceptibility to pathogens, further exacerbate the risks. Root exudation, which plays a crucial role in plant defence against drought and pathogens, is influenced by both water stress and pathogens. However, the interactive effects of these abiotic and biotic factors are rarely studied. Methods: We conducted a controlled environment experiment to investigate the effects of moderate drought and simulated pathogen attack (using pipecolic acid, an inducer of systemic acquired resistance) on the rates of root exudation of total organic carbon (TOC) and total nitrogen (TN) of four tomato cultivars grown in potting soil. Results: Drought increased the exudation of TOC and TN per unit of root area, while pipecolic acid did not have any significant effect. Furthermore, there was no interaction observed between the abiotic and biotic factors. However, due to the reduction in plant and root biomass caused by drought, the total exudation per plant remained similar between control and water-limited plants. Additionally, pipecolic acid reduced the carbon-to-nitrogen ratio of exudates and increased the total exudation of TN. Conclusion: The increased exudation observed in drought-stressed plants may serve as a strategy to maintain root and rhizosphere activity despite reduced root growth. Notably, the impact of drought differed among the tested cultivars, highlighting their diverse levels of drought tolerance. This emphasises the importance of preserving a wide range of crop cultivars to ensure food security under increasing drought. [ABSTRACT FROM AUTHOR]

Tomato (Solanum lycopersicum L.) crop is well-known for its versatility worldwide and is also recognized as model species used extensively for various genetic studies. The aim of this research was to investigate both inter and intra-genetic diversity present among various tomato genotypes. This investigation was carried out through a comprehensive analysis encompassing morphological observations, biochemical assessments, and the utilization of SSR markers. A total of 15 discrete agro-morphological traits and six biochemical traits were undertaken in the current study for evaluating the analysis of variance, genetic parameters and correlation. The analysis of variance indicated significant differences across genotypes for all 15 agro-morphological traits and 6 biochemical traits tested, indicating that the experimental material included considerable variability. Morphological clustering divided the genotypes into 2 clusters and the genotype wise distance matrix was obtained to identify the most diverse genotypes. PCA analysis was conducted to understand the directive relation of traits and magnitude of variability contributed by them. SSR profiling with 24 primers identified 44 alleles with 1.83 as mean number of alleles/SSR with an average PIC value of 0.31. Structure analysis revealed two sub-populations (K = 2). The AMOVA indicated that 98% of the total variation was present within populations. This study presents a roadmap for composing future breeding strategies for integrating desirable traits in novel tomato lines that combine robustness and nutritive value. [ABSTRACT FROM AUTHOR]

Tomato transgenics expressing dsRNA against FoFLPs act as biofungicides and result in enhanced disease resistance upon Fol infection, by downregulating the endogenous gene expression levels of FoFLPs within Fol. Fusarium oxysporum f. sp. lycopersici (Fol) hijacks plant immunity by colonizing within the host and further instigating secondary infection causing vascular wilt disease in tomato that leads to significant yield loss. Here, RNA interference (RNAi) technology was used to determine its potential in enduring resistance against Fusarium wilt in tomato. To gain resistance against Fol infection, host-induced gene silencing (HIGS) of Fol-specific genes encoding for fasciclin-like proteins (FoFLPs) was done by generating tomato transgenics harbouring FoFLP1, FoFLP4 and FoFLP5 RNAi constructs confirmed by southern hybridizations. These tomato transgenics were screened for stable siRNA production in T0 and T1 lines using northern hybridizations. This confirmed stable dsRNAhp expression in tomato transgenics and suggested durable trait heritability in the subsequent progenies. FoFLP-specific siRNAs producing T1 tomato progenies were further selected to ascertain its disease resistance ability using seedling infection assays. We observed a significant reduction in FoFLP1, FoFLP4 and FoFLP5 transcript levels in Fol, upon infecting their respective RNAi tomato transgenic lines. Moreover, tomato transgenic lines, expressing intended siRNA molecules in the T1 generation, exhibit delayed disease onset with improved resistance. Furthermore, reduced fungal colonization was observed in the roots of Fol-infected T1 tomato progenies, without altering the plant photosynthetic efficiency of transgenic plants. These results substantiate the cross-kingdom dsRNA or siRNA delivery from transgenic tomato to Fol, leading to enhanced resistance against Fusarium wilt disease. The results also demonstrated that HIGS is a successful approach in rendering resistance to Fol infection in tomato plants. [ABSTRACT FROM AUTHOR]

The South American tomato pinworm (Tuta absoluta) is a major pest of tomatoes that causes drastic yield losses. Some wild tomato genotypes are constitutively resistant to T. absoluta, whereas most commercial genotypes are susceptible. However, exogenous salicylic acid (SA) application may induce resistance to this herbivore in tomatoes. Since herbivory also reduces crop production by affecting photosynthesis, chlorophyll a fluorescence (ChlF) represents a powerful tool for identifying potential and easily addressed resistance indicators. Therefore, we compared the ChlF patterns of two commercial genotypes (Alambra and Redenção) and one wild-resistant genotype (Solanum habrochaites var. hirsutum) treated with 540 µM SA or water (control), correlating their ChlF pattern with feeding damages caused by T. absoluta. Our results showed that SA reduced the overall plant damage in Alambra at 7, 21, and 35 days after infestation (DAI), and the consumed leaf area in Redenção and hirsutum 60 DAI. The ChlF analysis showed that SA increased the electron transfer rate (ETR), the regulated energy loss of PSII (Y(NPQ)), the non-regulated energy loss (Y(NO)), and reduced the efficiency of open PSII reaction centers ( F v ′ / F m ′ ) and photochemical quantum yield (YII) in all genotypes. F o ′ , F m ′ , and F v ′ of commercial genotypes were higher than in the wild genotype. Feeding damage was positively correlated with F o ′ , F m ′ , and F v ′ , and negatively correlated with Y(NO) and ETR. These results indicate that ETR and Y(NO) might be useful for indicating salicylic acid-induced resistance against T. absoluta, while F o ′ , F m ′ , and F v ′ might indicate constitutive resistance. [ABSTRACT FROM AUTHOR]

Early blight (EB), caused by the dominant species Alternaria alternata, is a major global disease of tomato (Solanum lycopersicum L.; Solanaceae) reducing the vegetative organs and causing losses. Sustainable food production mainly depends on the rational use of chemical fertilizers and fungicides in integrated plant disease management. Hence, the fungicidal activity of ortivatop® (azoxystrobin + difenoconazole), Signum WG 33.4% (pyraclostrobin + boscalid) and daconyl SC 72% (chlorothalonyl) was evaluated against tomato EB disease under field conditions. Two experiments were conducted during the cropping seasons from 2019 to 2020 in three regions. The experimental design was a randomized block with 4 replications using Ortivatop® (ORT) at three doses of -900, -1100 and -1300 ml. ha−1 (recommended doses of the company), daconyl (DAC) 2 l. ha−1 and Signum (SIG) 0.5 l. ha−1. The findings showed that ORT-1300 (20.6%) and DAC (22.7%) resulted in the lowest EB disease severity, followed by SIG (25.7%), ORT-1100 (26.9%) and ORT-900 (31.7), in contrast to 59.1% of the control. Compared with treatment without fungicide, all fungicides reduced the AUDPC (area under disease progress curve) and provided an increase in productivity. ORT-1300 ml ha−1 showed the greatest reduction in AUDPC by up to 70% and increased tomato yield by threefold more than the untreated control. Therefore, the current study suggests that foliar spraying with ORT-1300 ml. ha−1 at all three growth stages, is an ideal solution for EB disease management. [ABSTRACT FROM AUTHOR]

Botrytis cinerea is one of the most destructive fungal pathogens which causing gray mold in a wide range of hosts including vegetables, crops, and fruits all around the world. Plants are capable of influencing the rhizospheric microbial community via root exudates (REs), which may play an important role in plant pathogen suppression. In the present study, tomato plants (Solanum lycopersicum) were pre-treated with the endophytic strain Pseudomonas chlororaphis PA6 (P.c PA6) or the chemical elicitor β-aminobutyric acid (BABA), and then exposed to foliar pathogens. Subsequently, the variation of root exudates and the effects on the rhizospheric bacterial community were evaluated. Metabolite profiling analysis by GC–MS/MS showed a total of 22–26 metabolites, mainly including organic acids and ester compounds in the REs of tomato seedlings in the treatment groups. P.c-conditioned plants exhibited relatively higher exudation of gluconic acid, malic acid, and lauric acid as well as lower levels of phthalate derivatives. By contrast, sorbitol was eminently detected in REs of tomato seedlings conditioned with BABA. Amplicon sequencing of the 16S rDNA demonstrated that the rhizobacterial community structure did not show much difference between groups at the phylum level, and higher proportions of bacteria from the orders Proteobacteria, Bacteroidetes, Actinobacteria, and Firmicutes were found. However, exogenous treatments altered the bacterial community at the genus level and mainly shifted the abundance of Pseudomonas, Neorhizobium, Acinetobacter, and Lactobacillus in the tomato rhizosphere, which are known beneficial bacteria positively correlated with disease control and growth promotion. The analysis indicated that specific phytochemicals from root exudates promoted different bacterial communities. Taken together, our results indicate that plant root exudates modulate the root-associated microbial community structure by selecting a group of beneficial microbes to shape a high-quality microbial consortium, which can ultimately support plant health and productivity. [ABSTRACT FROM AUTHOR]

Seed priming with nanoparticles (NPs) has gained considerable scientific attention; especially in regulating seed metabolism and signaling pathways, to establish seedling with improved germination in stress condition. Hence, the present study was conducted to understand the effect of zinc oxide nanoparticles (ZnO-NPs) as a seed priming agent on physio-biochemical and seed quality parameters of tomato (Solanum lycopersicum L.) under various salinity stress level (50 and 100 mM NaCl). Results showed that significant decrease was recorded in seed quality, physiological and biochemical parameters in unprimed seeds under 50 and 100 mM NaCl salinity stress condition, respectively as compared to control (without NaCl condition). However, ZnO NP @ 750 ppm for 6 h duration was found to notably increase the germination (4.8 and 12.6%), seed vigour index I (42.6 and 69%), II (43.1 and 68.1%), photosynthetic pigments (28.9 and 33.1%), TSS (27.0 and 26.5%), soluble protein (14.2 and 15.1%), phenol (40.4 and 34.1%), proline (59.0 and 62.1%) and antioxidant potential, however, the mean germination time (12.6 and 14.1%) was found to decrease under 50 and 100 mM NaCl salinity stress conditions, respectively, as compared to unprimed seeds. The genotype, QA001 performed significantly better than QA002 genotype under both control and salinity stress condition. Overall, seed priming with ZnO NP significantly enhanced chlorophyll content, enzymatic and non-enzymatic antioxidative defense mechanism and osmotic adjustment, which in turn reduced ROS accumulation and lipid peroxidation in cell membrane in tomato at the early seedling stage. [ABSTRACT FROM AUTHOR]

Tomato is the most produced and consumed vegetable in Turkey, and has a great importance in farmers' income. In this study, bacterial disease surveys were carried out in 130 plastic covered greenhouses in the center and eight district neighborhoods of Mersin province, Turkey from January to May, 2019 and 2020 growing periods, respectively. Suspicious tomato plants showing typical disease symptoms such as stem rot, pith necrosis and secondary root formation on the stem were collected from twelve different greenhouses. The representative bacterial strains (n = 20) were initially characterized based on pathogenicity test on tomato seedlings, phenotypic characteristics, and then identified as Stenotrophomonas spp., and Paenibacillus spp. according to their protein fingerprint patterns obtained by MALDI TOF MS system. The identification of three strains was further confirmed by sequencing of 16 S rDNA. According to BLAST analysis, the strains shared 99–100% identity with Stenotrophomonas rhizophila, Stenotrophomonas chelatiphaga and Paenibacillus amylolyticus strains deposited in GenBank. The prevalences of tomato inner pith necrosis and stem rot caused by Paenibacillus amylolyticus and Paenibacillus polymxa and pith necrosis caused by Stenotrophomonas spp. were 0.8% and 4.6%, respectively in the area. Representative bacterial strains were further tested for copper sensitivity in vitro, and, all strains were resistant for 1 mM copper amended KB media. This study represented the first report of newly introduced stem and core rot and pith necrosis caused by Paenibacillus amylolyticus, Paenibacillus polymxa and Stenotrophomonas spp., on tomato in Turkey. [ABSTRACT FROM AUTHOR]

Tomato production is significantly harmed by the interruption of fungal pathogens, i.e., Alternaria solani, the causal agent of early blight, which is responsible for substantial yield losses in tomato crops. In recent years, the application of silver-based green synthesized nanomaterials (AgNMs) has been documented as the best performer against various plant diseases. However, the knowledge about applying green-synthesized AgNMs for the management of early blight and its impact on the components of the antioxidant defense system, especially in tomatoes, still needs to be discovered. Therefore, in the current study, two green synthesized viz. wild gourd (Citrullus colocynthis) and rough cocklebur (Xanthium strumarium) AgNMs were applied at three different concentrations to check their efficacy against the early blight of tomatoes and the components of the antioxidant defense system of tomato plants. Results revealed that C. colocynthis-based AgNMs were found to be most effective and exhibited disease incidence of A. solani (22%) with a significant increase in tomato production (13%) along with the number of fruits/plants. Moreover, application of C. colocynthis-based AgNMs improved the concentration of ascorbic acid (1240, 997 µg/mL), total phenolic contents (950, 800 µg/mL), flavonoids (111, 88 mg/g), hydrogen peroxide (0.0013, 0.001 U/mg), amylase (110, 89 U/mL), chlorophyll a (0.31, 0.25 mg/g), chlorophyll b (0.22, 0.16 mg/g), and total chlorophyll (0.61, 0.50 mg/g) in treated plants of resistant and susceptible varieties of tomato respectively, than that of control. It is concluded that applying green synthesized AgNMs may be a viable alternative to synthetic chemicals for managing the early blight of tomatoes. [ABSTRACT FROM AUTHOR]

Regulated deficit irrigation (RDI) is a technique used to save water, increase water use efficiency (WUE) and nutrients in plants. This practice can be enhanced when combined with soil management. In addition, enhancing root architecture and improving the absorption of water and nutrients in deeper zones can be achieved through the application of phosphorus at depth. There is a scarcity of studies that evaluate the integrated effect of different management practices of fertilization and water on the fruit quality of tomato plants intended for the industry. Thus, the objective was to investigate the postharvest responses of fruit quality and cell wall metabolism of the industry tomato 'Heinz 9553'. Two irrigation frequencies (IF) (one and seven days) were implemented in the plots and three soil management models (conventional fertilization + limestone [FL]; conventional fertilization + limestone + gypsum [FLG]; conventional fertilization + limestone + gypsum + phosphorus applied in depth [FLGP]) were implemented in the subplots. Variables that affects the quality parameters (reducing sugars, phenolic compounds, carotenoids, pectinolytic enzymes) were evaluated. The results showed that the combined management FLG and IF of seven days provided increase in soluble solids, reducing sugars, soluble solids/titratable acidity ratio, dry matter, phenolic compounds and total carotenoids in the fruits. It was also found that the firmness of the pulp was higher in the seven-day IF treatment and was inversely related to the activity of the enzymes pectin methylesterase and polygalacturonases. The combined fertilization and water management strategies promoted improvements in quality and postharvest cell wall firmness of the industrial tomato 'Heinz 9553'. Therefore, the combined soil and water management strategies FLG and FLGP with IF of seven days are recommended for field cultivation of tomato for industrial processing. [ABSTRACT FROM AUTHOR]

Articular cartilage defect treatment is a very important problem because its therapeutic options are not successful enough. Due to the weak self-repairing capacity of the avascular cartilage, even minor damage can progress and cause joint damage leading to osteoarthritis. Although various treatment strategies have been developed to repair damaged cartilage, cell- and exosome-based therapies are promising. Plant extracts have been used for decades, and their effects on cartilage regeneration have been studied. Exosome-like vesicles, which are secreted by all living cells, are involved in cell-to-cell communication and cell homeostasis. The differentiation potential of exosome-like vesicles isolated from S. lycopersicum and C. limon, which are known to have anti-inflammatory and antioxidant properties, was investigated in the differentiation of human adipose-derived mesenchymal stem cells (hASCs) into chondrocytes. In order to obtain tomato-derived exosome-like vesicles (TELVs) and lemon-derived exosome-like vesicles (LELVs) Aquous Two- Phase system was performed. Characterisation of isolated vesicles based on size, shape were achived via Zetasizer, NTA FAME analysis, and SEM techniques. These results showed that TELVs and LELVs increased cell viability and did not show any toxic effects on stem cells. Although TELVs triggered chondrocyte formation, LELVs downregulated. The expression of ACAN, SOX9, and COMP, known as chondrocyte markers, was increased by TELV treatment. In addition, protein expression of the two most important proteins, COL2 and COLXI, found in the extracellular matrix of cartilage, increased. These findings suggest that TELVs can be used for cartilage regeneration, and may be a novel and promising treatment for osteoarthritis. [ABSTRACT FROM AUTHOR]

Phosphorus (P) is a vital limiting nutrient element for plant growth and yield. In Morocco, the natural phosphate rock extractions generate significant amounts of phosphate wash sludge (PS), which could be reused productively, thus creating another added value for farmers. The present study aimed to demonstrate the combination effect of soil amendment by two different PS concentrations (1% and 5%) associated with three phosphate-solubilizing bacteria (PSB) consortia (C1, C2, and C3), isolated from phosphate mining sludge, on plant growth and nutrient uptake in tomato seedlings (Solanum lycopersicum). The results obtained showed that this bioformulation significantly improved P solubilization and plant growth compared to control conditions. Of all the combinations, C3-inoculated soil amended with 5% PS was the most effective in significantly improving plant height and dry and fresh biomass of shoots and roots. P solubilization and its availability for tomato seedlings uptake were maximal with the bioformulation (C3 + 5% PS). This latter enhanced P and potassium (K) uptake by 27.89 and 38.81% in shoots and 38.57% and 74.67% in roots, respectively, compared to non-inoculated soil amended with 5% PS. The highest flowering rate (200 %) was recorded in C3-inoculated soil amended with 5% PS. Supporting these results, the principal component analysis discriminated this bioformulation (C3 + 5% PS) from the other combinations. Our results open up prospects for upgrading phosphate sludge enriched with PSB consortia as a biofertilizer that can be used in ecofriendly agriculture integrated into the circular economy. [ABSTRACT FROM AUTHOR]

Biostimulants obtained from seaweeds contain excellent nutrient sources to enhance plant growth and high crop yield. In this study, the seaweed liquid extract (SLE) was prepared from three seaweeds, namely Ulva intestinalis extract (UIE), Portieria hornemannii extract (PHE), and Turbinaria ornata extract (TOE). The SLE was categorized into seven possible combinations (single SLE and mixture of SLE), and the combinations were diluted into six strengths (minimum of 10%, subsequently 20%, 30%, 40%, 50%, and a maximum of 100%). The SLE preparations were evaluated for their growth stimulation properties on Solanum lycopersicum seeds and plants in the pot study. The plants treated with UIE (30%) exhibited a notable response in seed germination (90%); improved growth parameters such as plant height (shoot length (51%), root length (71%)), biomass (fresh weight (60%), dry weight (65%)), leaf parameter (leaf count (55%), leaf area (212%)), biochemical content (carbohydrates (83%), proteins (78%), amino acids (68%), phenolics (106%)), and pigment content (carotenoid (58%), chlorophyll a (94%), chlorophyll b (74%)) when compared with control (water). Further, the UIE (30%) displayed an upsurge (95%) in the yield (2037.5 g/ plant) when compared with water-treated plants (1042.3 g/ plant). Based on the present study, the SLE (particularly UIE) illustrated better biostimulant activity on S. lycopersicum. The results suggest that SLE prepared from seaweed can be used as a better choice of fertilizer due to its biostimulant activity. [ABSTRACT FROM AUTHOR]

Key message: Overexpression of SlPRE3 is detrimental to the photosynthesis and alters plant morphology and root development. SlPRE3 interacts with SlAIF1/SlAIF2/SlPAR1/SlIBH1 to regulate cell expansion. Basic helix–loop–helix (bHLH) transcription factors play crucial roles as regulators in plant growth and development. In this study, we isolated and characterized SlPRE3, an atypical bHLH transcription factor gene. SlPRE3 exhibited predominant expression in the root and moderate expression in the senescent leaves. Comparative analysis with the wild type revealed significant differences in plant morphology in the 35S:SlPRE3 lines. These differences included increased internode length, rolling leaves with reduced chlorophyll accumulation, and elongated yet fewer adventitious roots. Additionally, 35S:SlPRE3 lines displayed elevated levels of GA3 (gibberellin A3) and reduced starch accumulation. Furthermore, utilizing the Y2H (Yeast two-hybrid) and the BiFC (Bimolecular Fluorescent Complimentary) techniques, we identified physical interactions between SlPRE3 and SlAIF1 (ATBS1-interacting factor 1)/SlAIF2 (ATBS1-interacting factor 2)/SlPAR1 (PHYTOCHROME RAPIDLY REGULATED 1)/SlIBH1 (ILI1-binding bHLH 1). RNA-seq analysis of root tissues revealed significant alterations in transcript levels of genes involved in gibberellin metabolism and signal transduction, cell expansion, and root development. In summary, our study sheds light on the crucial regulatory role of SlPRE3 in determining plant morphology and root development. [ABSTRACT FROM AUTHOR]

Plant-herbivore interactions have been extensively studied in tomato plants and their most common pests. Tomato plant chemical defenses, both constitutive and inducible, play a role in mediating these interactions. Damaged tomato plants alter their volatile profiles, affecting herbivore preferences between undamaged and damaged plants. However, previous studies on tomato volatiles and herbivore preferences have yielded conflicting results, both in the volatile chemistry itself as well as in the attraction/repellent herbivore response. This study revisits the volatile-mediated interactions between tomato plants and two of their main herbivores: the leafminer Tuta absoluta and the whitefly Trialeurodes vaporariorum. Tomato plant volatiles were analyzed before and after damage by each of these herbivores, and the preference for oviposition (T. absoluta) and settling (T. vaporariorum) on undamaged and damaged plants was assessed both after conspecific and heterospecific damage. We found that both insects consistently preferred damaged plants over undamaged plants. The emission of herbivore-induced plant volatiles (HIPVs) increased after T. absoluta damage but decreased after T. vaporariorum damage. While some of our findings are in line with previous reports, T. absoluta preferred to oviposit on plants damaged by conspecifics, which differs from earlier studies. A comparison of HIPVs emitted after damage by T. absoluta and T. vaporariorum revealed differences in up- or down-regulation, as well as significant variations in specific compounds (12 for T. absoluta and 26 for T. vaporariorum damaged-plants). Only two compounds, β-caryophyllene and tetradecane, significantly varied because of damage by either herbivore, in line with the overall variation of the HIPV blend. Differences in HIPVs and herbivore preferences may be attributed to the distinct feeding habits of both herbivores, which activate different defensive pathways in plants. The plant's challenge in simultaneously activating both defensive pathways may explain the preference for heterospecific damaged plants found in this study, which are also in line with our own observations in greenhouses. [ABSTRACT FROM AUTHOR]

Plant pathogens cause significant crop losses worldwide and present significant challenges to reliable food systems. The hemibiotroph Phytophthora capsici is ranked within the top 10 most problematic oomycete plant pathogens. P. capsici induces significant damage to plants by causing root rot, stem blight, and fruit rot, leading to decreased crop yields, economic losses, and increased plant susceptibility to secondary infections. The current study tested the hypothesis that plant growth promoting rhizobacteria (PGPR), namely Bacillus velezensis UQ9000N and Pseudomonas azotoformans UQ4510An, have inhibitory effects against various fungi and oomycetes. This study also hypothesised that the plant genotype affects the capability of UQ4510An to control P. capsici infection. Our results revealed that B. velezensis UQ9000N and P. azotoformans UQ4510An inhibited the growth of several plant pathogens by 50% or higher. These bacteria also induced abnormal mycelial morphology of P. capsici and Fusarium oxysporum f. sp. lycopersici. Moreover, P. azotoformans UQ4510An exhibited anti-oomycete activity in vitro and in planta, by reducing symptoms of P. capsici infection in various tomato plant cultivars in a genotype-dependent manner. Some tomato cultivars which presented less improvements of phenotypic parameters from the UQ4510An inoculation in the absence of the pathogen had a more pronounced reduction in symptoms upon P. capsici infection. Furthermore, our results indicated that the main biocontrol mechanism of P. azotoformans UQ4510An against P. capsici is a combination of direct antagonism and induction of induced systemic resistance (ISR) involving a hypersensitive response (HR) in the plant host at early stages of infection. [ABSTRACT FROM AUTHOR]

Key message: The novel interkingdom PGPM consortia enhanced the ability of plant growth promotion and disease resistance, which would be beneficial to improve plant growth in sustainable agriculture through engineering microbiome. Plant growth-promoting microbes (PGPMs) play important roles in promoting plant growth and bio-controlling of pathogens. Much information reveals that the plant growth-promoting ability of individual PGPM affects plant growth. However, the effects of the PGPM consortia properties on plant growth remain largely unexplored. Here, we characterized three new PGPM strains including Rhodotorula graminis JJ10.1 (termed as J), Pseudomonas psychrotolerans YY7 (termed as Y) and P. chlororaphis T8 (termed as T), and assessed their effects in combination with Bacillus amyloliquefaciens FZB42 (termed as F) on plant growth promotion and disease prevention in Arabidopsis thaliana and tomato (Solanum lycopersicum) plants by investigating morphological changes, whole-genome sequencing and plant growth promoting (PGP) characterization. Results revealed that the three new strains R. graminis JJ10.1, P. psychrotolerans YY7 and P. chlororaphis T8 had the potential for being combined with B. amyloliquefaciens FZB42 to form interkingdom PGPM consortia. The combinations of R. graminis JJ10.1, B. amyloliquefaciens FZB42, and P. psychrotolerans YY7, i. e. JF and JYF, exhibited the strongest ability of synergetic biofilm production. Furthermore, the growth-promotion abilities of the consortia were significantly enhanced compared with those of individual strains under both inoculation and volatile organic compounds (VOCs) treatment. Importantly, the consortia showed stronger abilities of in planta disease prevention than individual strains. Findings of our study may provide future guidance for engineering the minimal microbiome communities to improve plant growth and/or disease resistance in sustainable agriculture. [ABSTRACT FROM AUTHOR]

The tomato is a major crop worldwide and is one of the five most consumed vegetables in Germany. Stemphylium species including S. eturmiunum, S. gracilariae, S. lycii, S. lycopersici, S. rombundicum, S. simmonsii, S. solani, and S. vesicarium have been identified as tomato pathogens in various countries. In Germany, multiple instances of S. lycopersici and S. solani affecting tomato plants have been documented; however, only one incident of S. vesicarium has been reported in 1972. S. vesicarium is known to cause yellowish-brown spots on tomato leaves, which can ultimately lead to defoliation and reduced fruit yield. Therefore, it is crucial to identify the S. vesicarium that cause this disease accurately. In this study, S. vesicarium was isolated from necrotic tomato plants in organic farms located in northern and southern regions of Germany. Single spore isolates were generated and identified as S. vesicarium based on morphological characteristic and molecular analyses using nucleotide sequences of the internal transcribed spacer (ITS) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH). Koch´s postulates were fulfilled and revealed that S. vesicarium is the causal agent of brown spot on the samples adding a new account of the species. [ABSTRACT FROM AUTHOR]

Post-harvest fruit and vegetable rot produced by Botrytis cinerea (Helotiales: Sclerotiniaceae) causes significant reductions in food availability and drastically increases economic losses. The use of microbial-based tools for pathogen management holds promise. In particular, volatile organic compounds (VOCs) emitted by microbes (e.g., bacterial compounds) are becoming increasingly more frequent as an alternative to chemical and physical treatments. In this study, we performed three laboratory experiments to investigate the effects of VOCs emitted by two gram-negative entomopathogenic bacteria, Xenorhabdus nematophila, and Photorhabdus laumondii subsp. laumondii, on the infection and growth of the pathogenic mold B. cinerea on post-harvest red grapes and tomatoes. In addition, we evaluated the preventive effects of these bacterial VOCs against pathogens in post-harvest wounded and intact grapes. Overall, VOCs emitted by X. nematophila and P. laumondii limited the lesion area of B. cinerea to 0.5% and 2.2%, respectively, on the grapes. Similarly, VOCs emitted by X. nematophila and P. laumondii limited the lesion area of B. cinerea to 0.5% and 0.02%, respectively, in tomatoes. In addition, the emission of VOCs by both bacteria showed strong preventive fungal effects. In particular, VOCs emitted by P. laumondii reduced to 13% B. cinerea incidence in damaged grapes exposed to VOCs. Moreover, intact grapes exposed to VOCs emitted by X. nematophila and P. laumondii decreased B. cinerea incidence by 33%. This study provides insightful information about a potential novel bacteria-based tool that can be used as an alternative in the integrated control of post-harvest diseases. [ABSTRACT FROM AUTHOR]

Plant-associated bacteria exhibit diverse chemical means to protect plants from the pathogens. The present study has been conducted to evaluate the volatile-mediated antifungal activity of Serratia sp. NhPB1 isolated from the pitcher plant against the notorious pathogen Pythium aphanidermatum. The study has also evaluated the protective effect of NhPB1 on Solanum lycopersicum and Capsicum annuum leaves and fruits against P. aphanidermatum. From the results, NhPB1 was found to have remarkable activity against the tested pathogen. The isolate was also found to impart disease protection in selected plants as evidenced by the morphological changes. Here, the leaves and fruits of S. lycopersicum and C. annuum control which were treated with the uninoculated LB and distilled water were found to have the presence of P. aphanidermatum growth with lesions and decaying of tissues. However, the NhPB1-treated plants did not show any symptoms of fungal infection. This could further be confirmed by the microscopical examination of tissues by propidium iodide staining. Here, the normal architecture of leaf and fruit tissues could be observed in the NhPB1-treated group, but the tissue invasion by P. aphanidermatum was observed in the control group which further confirms the promises of selected bacteria for biocontrol applications. [ABSTRACT FROM AUTHOR]

Phytophthora infestans populations and lineages vary widely in their specificity to potato and tomato hosts, from specialisation to generalism. However, generalists that displace others and became dominant on both hosts are relatively uncommon. Generalists may have lower fitness compared to specialists on the host of the latter, which could explain their coexistence at many locations. Lesion size is an aggressiveness metric closely related to fitness in P. infestans. A trade-off between generalism and lesion growth rate on the original host can explain the variation among blight populations. I collated the data from cross-inoculation trials on potato and tomato isolates to test this trade-off. In addition, other metrics related to disease symptoms were included to test whether the degree of specificity is different between populations from potato and tomato, and to explore whether specificity had changed over time. The results indicate a trade-off between generalism and lesion growth rate where higher specificity was associated with significantly faster lesion growth on the original host at the population-level, but not at the lineage-level. Potato and tomato isolates were overall not significantly different in specificity, but tomato isolates tended towards generalism with time. These findings indicate that specialists may avoid displacement on their host by generalists through faster lesion growth, and help explain the common co-occurrence of generalists and specialists. However, a few invasive generalists can rapidly displace competitors and became dominant on both hosts across a broader region. It is likely that important exceptions exist to this trade-off. [ABSTRACT FROM AUTHOR]

Strigolactones (SLs) are newly identified unique class of sesquiterpenoid phytohormones. Their role in seed germination and seedling growth and development is yet to be elucidated. As we know that the germination of seed is critical phase in a plant's life cycle. Therefore, the present experiment aimed to study the function of strigolactone (GR24) in the regulation of physiological and biochemical mechanisms related to seed germination, and the growth and development of five tomato genotypes viz. Crystal Select (V1), Super Strain-B (V2), Riogrand (V3), Tomate Tres Cantos (V4) and Tomato Strain-8 (V5). In the present studies, we conducted two experiment (1) Petri dish experiment for the study of germination attributes and (2) pot experiment for growth and physio-biochemical study. Different concentrations of SL were directly supplied to the Petri dishes for seed germination. Basal doses of SL were supplied to seedlings grown in pots. Increasing levels of SL triggered the germination potential of all genotypes of tomato by increasing the activity of alpha-amylase (α-A) activity and protease (Ptase). The concertation of 0.20 μM of SL increased α-A activity, Ptase activity, germination %, germination index, vigor index by 54.54%, 53.82%, 21.63%, 60.31% and 302.39%, respectively, as compared to respective controls. Among the treatments and genotypes, 0.20 μM of SL and cultivar V3 proved best by producing maximum values for these attributes. Similarly, increasing levels of SL increased growth parameters (shoot and root length, shoot and root fresh weight, and shoot and root dry weight) and physio-biochemical characteristics [Chlorophyll (Chl) a and b, net photosynthetic rate, stomatal conductance, internal CO2 concertation, carbonic anhydrase activity, proline (Pro) and total soluble carbohydrates (TSC) content, and activity of pyrroline-5-carboxylate synthase, nitrate reductase, nitrite reductase]. It may be concluded that exogenous SL improved germination potential by stimulating α-A activity and Ptase, and plant growth and development by increasing biosynthesis of Chl, Pro and TSC, photosynthesis process, and nitrogen assimilation. [ABSTRACT FROM AUTHOR]

Several crops (tomato, eggplant, sweet pepper, and cucumber) were used to examine the impact of continuous (24 h a day) lighting on photosynthetic characteristics of plants grown permanently at 26°C and those exposed daily to short-term (2 h) cooling at 10°C (temperature-drop treatments). The plant response was assessed by indices characterizing the pigment complex and the photosynthetic activity of leaves. Growing plans under continuous light at a constant temperature resulted in leaf photodamage and photoinhibition in all four species, although to varying degrees. The temperature-drop treatments prevented the photodamage of leaves under continuous light in all species and enabled high sustainable levels of photosynthetic activity in tomato, pepper, and cucumber. The results suggest that temperature-drop treatments can be regarded as an agricultural technique that exploits the benefits of continuous lighting while mitigating the negative effects of constant light. However, the effectiveness of this technique would depend on the choice of optimal intensities and durations of the drop treatment since these parameters may vary depending on plant species. [ABSTRACT FROM AUTHOR]

Tomato (Solanum lycopersicum L.) is an important crop and, due to the existence of wild related species (Solanum section Lycopersicon), a model for studying the development of the fleshy fruit. In the study, expression analysis of sugar uniporter genes SWEET1а, 1b, 1e, 3, 7a, 10a, 12c, 14, and 15 in tomato species and cultivars was carried out. In cv. Heinz (S. lycopersicum), genes that are most active in roots (SWEET1e, 3, 10a, and 12c), leaves (SWEET1a, 1e, 3, 10a, and 12c) and flowers (SWEET1a, 1b, 7a, 10a, 12s, 14, and 15) were revealed. The growth of the fruit is accompanied by an increase in the level of the SWEET 110a and 12c transcripts; maturation of the fruit is accompanied by an increase in the level of the SWEET 1a and 15 transcripts. Differential expression of the SWEET1a, 1b, 12c, and 15 genes in the ripe fruit of inbred lines obtained from crossing of S. lycopersicum cv. M82 × S. pennellii was demonstrated. qRT-PCR analysis showed that the expression of the SWEET1a and 12c genes is common for ripe fruit of the analyzed tomato species, while the expression of the SWEET1b and 10a genes is common for S. pennellii, S. habrochaites, and S. cheesmaniae. It was determined that the fructose : glucose ratio is equimolar in the accessions except for cv. Black Jack and White Beauty (fructose : glucose ≥ 1.10). Correlations between the level of SWEET gene transcripts and the ratio of hexoses was not revealed. [ABSTRACT FROM AUTHOR]

The release of Tamarixia triozae (Burks) (Hymenoptera: Eulophidae), a parasitoid of the potato psyllid, Bactericera cockerelli (Šulc) (Hemiptera: Triozidae), resulted in the successful establishment of the parasitoid in New Zealand. The parasitoid was released at more than 30 sites by the final year of the three-year study throughout New Zealand. Its continued presence over the three-year study was confirmed in two regions (Hawke's Bay and Canterbury). At one site in Canterbury, the parasitoid was released only in the first summer of this study (Nov. 2017–Feb. 2018). It was recovered from potato psyllid infested African boxthorn (Lycium ferocissimum Miers) foliage in the second and third summers at this site, demonstrating the parasitoid's ability to survive over successive winters. We found T. triozae parasitized nymphs at 24 sites of the 86 potato psyllid host plant sites surveyed within a 25 km radius of known release sites in Hawke's Bay. The parasitoid was found up to 24 km from the nearest known release site in Hawke's Bay. In Canterbury, the parasitoid was found up to 0.6 km from a known release site. Parasitism rates of 13.7–15.6% were estimated based on two post-release survey methods employed in this study. The parasitoid also feeds on psyllid nymphs so its establishment may lead to helping to reduce or delay potato psyllid populations from reaching damaging levels. Long-term monitoring is needed to determine the consequences of importing T. triozae on populations of potato psyllid. [ABSTRACT FROM AUTHOR]

Main conclusion: Tomato plant acclimation to a mild water stress implied tissue-specific hormonal and nutrient adjustments, being the root one of the main modulators of this response. Phytohormones are key regulators of plant acclimation to water stress. However, it is not yet clear if these hormonal responses follow specific patterns depending on the plant tissue. In this study, we evaluated the organ-specific physiological and hormonal responses to a 14 day-long mild water stress in tomato plants (Solanum lycopersicum cv. Moneymaker) in the presence or absence of the arbuscular mycorrhizal fungus Rhizoglomus irregulare, a frequently used microorganism in agriculture. Several physiological, production, and nutritional parameters were evaluated throughout the experiments. Additionally, endogenous hormone levels in roots, leaves, and fruits at different developmental stages were quantified by ultrahigh-performance liquid chromatography coupled to tandem mass spectrometry (UHPLC–MS/MS). Water deficit drastically reduced shoot growth, while it did not affect fruit production. In contrast, fruit production was enhanced by mycorrhization regardless of the water treatment. The main tissue affected by water stress was the root system, where huge rearrangements in different nutrients and stress-related and growth hormones took place. Abscisic acid content increased in every tissue and fruit developmental stage, suggesting a systemic response to drought. On the other hand, jasmonate and cytokinin levels were generally reduced upon water stress, although this response was dependent on the tissue and the hormonal form. Finally, mycorrhization improved plant nutritional status content of certain macro and microelements, specially at the roots and ripe fruits, while it affected jasmonate response in the roots. Altogether, our results suggest a complex response to drought that consists in systemic and local combined hormonal and nutrient responses. [ABSTRACT FROM AUTHOR]

Plant senescence is mediated by complex regulatory pathways. Any delay in the onset of senescence is linked with improved plant growth and fitness. In this work, we identified Solanum lycopersicum ACAULIS5 (SlACL5) gene, a close homolog of Arabidopsis thaliana ACAULIS5 (AtACL5), which shows higher expression in developing leaves, stem, and roots of tomato plants. We also observed that its expression was gradually decreased from young and mature leaves to leaves undergoing senescence. We demonstrated that its constitutive overexpression (35S::SlACL5) in Nicotiana tabacum resulted in increased plant growth and higher accumulation of pigments and delayed the senescence of leaves. We found that the average length of plants of 35S::SlACL5 OE lines was higher than the control plants. The anatomy of the stem of OE lines showed no major alterations in cortical and vascular tissues. However, the expression of xylem cell death marker NtMC9 was downregulated in these lines indicating delayed xylem cell death program. Furthermore, we observed that expression of early-stage and late-stage senescence-associated marker genes, NtSGR1 and NtSAG12 was greatly reduced in the leaves of OE lines showing delayed senescence process in the leaves. We show that OE plants have reduced levels of Reactive Oxygen Species (ROS) and activity of some of the antioxidant enzymes was reduced or misregulated. The MDA content was also found to be less in these lines. Relative chloroplast DNA (cpDNA) content and marker gene expression analysis also performed which show higher cpDNA content and increased expression of chloroplast marker genes, NtrpoA, NtrbcL, and NtpetB in OE lines suggesting higher chloroplast activity in OE lines than the control. We conclude that overexpression of SlACL5 in tobacco leads to altered plant development, higher chloroplast activity and chlorophyll contents, reduced ROS generation, and downregulated expression of senescence-associated marker genes, thereby delaying leaf senescence program which resulted in vigorous plant growth. [ABSTRACT FROM AUTHOR]

Plant growth-promoting rhizobacteria (PGPRs) are bacteria that colonize the plant roots. These beneficial bacteria have an influence on plant development through multiple mechanisms, such as nutrient availability, alleviating biotic and abiotic stress, and secrete phytohormones. Therefore, their inoculation constitutes a powerful tool towards sustainable agriculture and crop production. To understand plant-PGPRs interaction we present the classification of PGPR using machine learning and meta-learning classifiers namely Support Vector Machine (SVM), Kernel Logistic Regression (KLR), meta-SVM and meta-KLR to predict the presence of Bacillus megaterium inoculated in tomato root tissues using publicly available transcriptomic data. The original dataset presents 36 significantly differentially expressed genes. As the meta-KLR achieved near-optimal performance considering all the relevant metrics, this meta learner was afterwards used to identify the informative genes (IGs). The outcomes showed 157 IGs, being present all significantly differentially expressed genes previously identified. Among the IGs, 113 were identified as tomato genes, 5 as Bacillus subtilis proteins, 1 as Escherichia coli protein and 6 were unidentified. Then, a functional enrichment analysis of the tomato IGs showed 175 biological processes, 22 molecular functions and 20 KEGG pathways involved in B. megaterium–tomato interaction. Furthermore, the biological networks study of their Arabidopsis thaliana orthologous genes identified the co-expression, predicted interaction, shared protein domains and co-localization networks. [ABSTRACT FROM AUTHOR]

Main conclusion: NOR-like1 regulates tomato fruit size by targeting SlARF9, SlGRAS2, SlFW3.2, and SlFW11.3 genes involved in cell division and cell expansion. Fruit size is an important agricultural character that determines the yield of crops. Here, we found that NAC transcription factor NOR-like1 regulated fruit size by regulating cell layer number and cell area in tomato. Over-expressing NOR-like1 gene in tomato reduced fruit weight and size, whereas the knock-out of NOR-like1 increased fruit weight and size. At the molecular level, NOR-like1 binds to the promoter of SlGRAS2, SlFW3.2, and SlFW11.3 to repress their transcription, while it also binds to the promoter of ARF9 to activate its transcription. Overall, these results expand the biological function of NOR-like1 and deepen our understanding of the transcriptional network that regulates tomato fruit size. [ABSTRACT FROM AUTHOR]

Iron deficiency is a major factor limiting plant growth in alkaline soils. 14-3-3 proteins are a family of phosphoserine-binding proteins. Previous studies have shown that iron deficiency significantly induces the expression of 14-3-3 protein gene TFT7 in tomatoes. In this study, a virus-induced gene silencing (VIGS) system composed of pTRV1 and pTRV2 was used to investigate whether the induction of TFT7 expression was involved in regulating the iron uptake system in tomato roots. Co-inoculation with the modified viral vectors pTRV1 and pTRV2-TFT7 effectively silenced the expression of TFT7 in tomato roots. Simultaneously, due to TFT7 silencing, expressions of the transcription factor gene SlFER, ferric chelate reductase SlFRO1, and iron transporter gene SlIRT1 were significantly inhibited in iron-deficient roots. Additionally, TFT7 silencing significantly reduced ferric chelate reductase activity in iron-deficient tomato roots. Therefore, this study suggested that TFT7 is important for regulating the iron absorption system during iron deficient periods. [ABSTRACT FROM AUTHOR]

The biology and biotechnology of bacteriophages have been extensively studied in recent years to explore new and environmentally friendly methods of controlling phytopathogenic bacteria. Pseudomonas syringae pv. tomato (Pst) is responsible for bacterial speck disease in tomato plants, leading to decreased yield. Disease management strategies rely on the use of copper-based pesticides. The biological control of Pst with the use of bacteriophages could be an alternative environmentally friendly approach to diminish the detrimental effects of Pst in tomato cultivations. The lytic efficacy of bacteriophages can be used in biocontrol-based disease management strategies. Here, we report the isolation and complete characterization of a bacteriophage, named Medea1, which was also tested in planta against Pst, under greenhouse conditions. The application of Medea1 as a root drenching inoculum or foliar spraying reduced 2.5- and fourfold on average, respectively, Pst symptoms in tomato plants, compared to a control group. In addition, it was observed that defense-related genes PR1b and Pin2 were upregulated in the phage-treated plants. Our research explores a new genus of Pseudomonas phages and explores its biocontrol potential against Pst, by utilizing its lytic nature and ability to trigger the immune response of plants. Key points: • Medea1 is a newly reported bacteriophage against Pseudomonas syringae pv. tomato having genomic similarities with the phiPSA1 bacteriophage • Two application strategies were reported, one by root drenching the plants with a phage-based solution and one by foliar spraying, showing up to 60- and 6-fold reduction of Pst population and disease severity in some cases, respectively, compared to control • Bacteriophage Medea1 induced the expression of the plant defense-related genes Pin2 and PR1b [ABSTRACT FROM AUTHOR]

Tomato is an important vegetable crop worldwide and is well-liked by consumers. Aroma, as an essential indicator of tomato quality, is critical for tomato breeding improvement by investigating its main components and formation mechanism. In this study, we determined the volatiles of four cherry tomato varieties at the ripening stage which were chosen from the comprehensive acceptance ranking of quality using headspace solid-phase micro-extraction (HS-SPME) and gas chromatography-mass spectrometry (GC–MS). Subsequently, we made the exploration of the important aroma components and the determination of enzymatic activities at different growth periods in conjunction with consumer evaluation information. The odor activity values (OAV) of aroma volatiles demonstrated that 37 aroma compounds were the characteristic components of cherry tomato. The partial least squares regression (PLSR) results revealed that the primary characteristic flavor components leading to consumer approval were decanal, 2-isobutylthiazole, β-ionone, isobutyl cyanide, ethyl acetate, (E,E)-2,4-nonadienal, 2-pentyl-furan, hexanal, 2-octanol, and nonanal. Spearman's correlation analysis between enzymatic activity and volatile compound accumulation was used to uncover the potential mechanism of volatile metabolism in full-ripe cherry tomatoes. [ABSTRACT FROM AUTHOR]