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Agriculture has a significant environmental impact and is simultaneously called to major challenges, such as responding to the need to develop more sustainable cropping systems with higher productivity. In this context, the present study aimed to obtain lignin nanoparticles (LNs) from pomace, a waste product of the olive oil chain, to be used as a nanobiostimulant in tomato plants. The biostimulant effect of this biopolymer is known, but its reduction to nanometer size can emphasize this property. Tomato plants were subjected to different LN dosages (25, 50, and 100 mg L−1) by foliar application, and inductive effects on photosynthetic machinery, aerial and root biomass production, and root morphology were observed. The treated plants showed increased efficiency in catching and using light, while they reduced the fraction dissipated as heat or potentially toxic to cells for the possibility of creating reactive oxygen species (ROS). Finally, this benefit was matched by increased pigment content and a stimulatory action on the content of nitrogen (NBI) and antioxidant substances such as flavonoids. In conclusion, the present study broadens the horizon of substances with biostimulant action by demonstrating the validity and efficacy of nanobiostimulants obtained from biological residues from the olive oil production chain. [ABSTRACT FROM AUTHOR]

Osmotically dehydrated cherry tomatoes and spinach leaves were incorporated into Greek salad-type (including OD-treated and air-dried feta cheese trimmings and air-dried olive rings) and green salad-type (including OD-treated and air-dried feta cheese trimmings and roasted ground peanuts) ready-to-eat (RTE) product prototypes, respectively. The osmotic dehydration of cherry tomatoes and spinach leaves was conducted in a pilot scale setting (100 L) in a 60% glycerol-based solution at 35 °C and 25 °C for 180 min and 60 min, respectively. To quantify the moisture transfer between the three ingredients of different moisture content (and water activity), the moisture equilibrium curves for each ingredient of the RTE product were determined. The equilibrium water activity of RTE products was 0.86 and 0.76, respectively. The quality of the RTE products (more specifically, tomato and spinach color and texture, instrumentally measured and sensorially perceived, sensory characteristics) was evaluated. The shelf life of the prototypes (from 4 °C to 20 °C) was kinetically modeled based on sensory deterioration and microbial growth, using the zero-order kinetic model and the Gompertz model, respectively. In the case of the tomato-based product, a shelf life of 54 days (based on sensory deterioration) was achieved at 4 °C, a shelf-life extension of 40 days compared to untreated, fresh-cut tomato. The shelf life of the spinach-based product (based on sensory deterioration) was 36 days at 4 °C, 30 days longer when compared to untreated spinach. Our results indicate that osmotic dehydration was successful in significantly extending the shelf life of such products, contributing to the increased temperature resilience of their keeping quality and allowing for their distribution and storage in a variable cold chain. [ABSTRACT FROM AUTHOR]

Agricultural systems must improve their sustainability and productivity to meet the growing global demand for food. A cost-effective and sustainable way is the development of biostimulants from plants rich in bioactive compounds. This study aimed to test an aqueous extract from Lemna minor L. (duckweed) on tomato plants at different concentrations (LE—0.1, 0.5 and 1.0%—weight/volume, w/v). Photosystem I and II activity, linear electron flow (LEF), electrochemical gradient across the thylakoid membrane (ECSt), shoot biomass production, root phenotyping, pigment and metabolite content were studied. LE improved many of these traits, with LE 0.5% being the most effective dosage. Compared to the untreated samples, LE significantly stimulated photosystems to use light energy while reducing the amount lost as heat (PhiNPQ and NPQt) or potentially toxic to chloroplasts (PhiNO). These results were supported by the improved shoot biomass production (number of leaves and fresh and dry weight) and root traits (number of tips, surface, volume and fresh and dry weight) found for LE-treated samples compared to untreated controls. Finally, the study highlighted that LE increased pigment and flavonoid contents. In conclusion, the research indicates that this species can be an effective and eco-friendly tool to stimulate beneficial responses in tomato. [ABSTRACT FROM AUTHOR]

There is a growing demand for organic vegetable products. Increasing the marketable yield and quality of tomatoes through the use of optimal organic and inorganic fertilizers is a critical agronomic measure for crop productivity and soil health. However, little is known about the effects of Azolla on tomato productivity, fruit quality and soil organic changes. The aim of this study was to compare the effects of organic and inorganic fertilization on marketable yield and quality characteristics of tomato fruits. A pot experiment was conducted with four concentrations of Azolla and nitrogen in a completely randomized design. The results showed that Azolla has the potential to replace nitrogen and has a significant impact on fruit quality. The interactions of Azolla and nitrogen on the number of clusters per plant, the number of flowers per cluster, the proportion of fruit set, the number of fruits per cluster and the marketable fruit yield were significant. It can be concluded that the combination of Azolla and inorganic nitrogen fertilizer linearly increased the marketable yield and quality of tomato fruits. [ABSTRACT FROM AUTHOR]

Introduction: Phytoremediation is a cutting-edge and eco-friendly technique that utilizes plants to eliminate pollutants, including copper, which can pose risks to plants, animals, and humans. In the present study, the hyperaccumulator capabilities of the tomato plant (Lycopersicon esculentum) in the removal of copper, zinc, iron, and manganese from the soil was explored. Materials and Methods: The tomato plants were cultivated for 60 days in pots containing varying concentrations of copper, ranging from 250 to 1250 ppm. At specific time intervals of 15, 30, 45, and 60 days, plants of each concentration were harvested. Then the soils were analyzed using atomic absorption spectroscopy to determine the levels of copper, zinc, manganese, and iron. Results: The results indicated that zinc removal exhibited a higher rate compared to other metals, with a removal rate of up to 95.79%, while copper removal reached 87.7%. Furthermore, analysis after 60 days of treatment revealed that the aerial parts of the plants accumulated more metals than that of the roots. Additionally, the chlorophyll content in the leaves decreased at both low and high copper concentrations, compared to 500 ppm CuSo4. Conclusion: The tomato plant, L. esculentum indicated promising hyperaccumulator potential in the removal of copper, zinc, iron, and manganese. The current study emphasized the effectiveness of phytoremediation as a sustainable approach to abating copper pollution. [ABSTRACT FROM AUTHOR]

Drought associated with climate change is undoubtedly one of the most prodigious challenges facing agricultural production and human food security throughout the world. Regarding the increasing incidence and potency of drought under ongoing global warming, determining the potential impacts of water-deficit tension on insect demographic attributes is a key element in success of any management program. By subjecting the western flower thrips (WFT), Frankliniella occidentalis, to well-watered and water-stressed cherry tomato plants, the impacts of this stressor on thrips performance were assessed. The key life-history parameters of WFT on fully-irrigated plants (FIT), 80% and 60% FIT were compared. WFT performed worse on drought-stress plants. Thrips specimens developed faster on 60% FIT and the female individuals were less fecund. When reared on plants grown under 60% full irrigation treatment (FIT), WFT displayed lower net reproductive rates and intrinsic and finite rates of increase compared to those reared on stress-free plants. Moreover, with increasing water stress intensity, the sex ratio became more male-biased which might in turn cause mate shortages and consequently a reduction in population growth. Our analysis showed that activities of the enzymes CAT and POD are elevated under WS conditions, and this might be correlated with reduced WFT fitness. In total, 60% FIT drought stress could have the capacity to lessen the abundance and upsurge risk of this destructive pest species under future climate change scenarios. The knowledge gained in this study will aid tomato producers understand how drought stress impact WFT demographic traits, and to foresee if pesticide treatments will be required to manage this infamous pest. [ABSTRACT FROM AUTHOR]

Primary Goal: This study aims to determine the effect of tomato cookies on the iron levels of pregnant women in certain areas in Indonesia. Methods: This study used a quasi-experimental pretest and posttest control group design. A sample of 102 people with the same number per group was taken using simple random sampling. Tomato biscuits were given five pieces (@20 grams) every day/for seven days. Iron levels were measured during the pretest and posttest. Observation sheets, standard operating procedures, and haemoglobin levels based on laboratory tests were used. In comparison, data Analysis using Paired T-Test and Independent T-Test. Results: The majority of respondents were aged 20-35 years (90.4%), third trimester (58.1%), and multigravida (83.9%). The control group showed no significant difference between pretest and posttest haemoglobin levels (p=0.317). There was an increase in the Hb level of pregnant women after giving tomato Cookies as much as 1.77 g/dL with p=0.011. There was a significant difference in haemoglobin levels between the control and intervention groups (p=0.025). Conclusions: The provision of tomato cookies effectively increases the Hb levels of pregnant women. This intervention can be an alternative for preventing and treating anaemia in pregnant women. Pregnant women can consume tomato cookies together with the consumption of iron tablets. [ABSTRACT FROM AUTHOR]

The use of natural biostimulators on crops is an innovative approach, friendly to the environment and with beneficial effects on the quality of production. In this sense, the objective of this study was to evaluate the application of the Lignohumate biostimulator to the tomato crop on fruit quality, depending on the fertilization dose. This is a biofertilizer, consisting of a complex of potassium salts of humic and fulvic acids, supplemented with microelements. The biological material was represented by the 'Giraffe F1' tomato hybrid. The specifics of the variants were: V1 (Mt) - unfertilized, V2 - fertilized with 1 g/10 L water, V3 - fertilized with 1.5 g/10 L water, V4 - fertilized with 2.0 g/10 L water. The monitored quality parameters were: total soluble substance, titratable acidity, reducing carbohydrates, ascorbic acid, total carotene, total lycopene and total polyphenols. The recorded data showed that all quality parameters had significant values compared to the control in the variants fertilized with Lignohumate 1.5 g/10 L water and 2.0 g/10 L water. [ABSTRACT FROM AUTHOR]

Seed coating using antagonistic fungi protects seeds and plants against pathogens. In this research, the effect of tomato seed coating was studied using the endophytic fungus Acrophialophora jodhpurensis against Rhizoctonia solani in vivo. Seed coating was done using the spores of A. jodhpurensis supplemented with 1% edible sucrose, 0.5 % carboxymethyl cellulose (CMC), or 0.5 % molasses as stickers. The greenhouse studies showed that the plant roots were colonized by this endophytic fungus very well at 30 days post-cultivation. The colonization of the roots in sucrose and carboxymethyl cellulose treatments was 80.55%, and in molasses treatment was 69.44%. This beneficial fungus significantly reduced the disease index of R. solani on detached leaf discs and tomato seedlings compared to the control. Also, the formation of pathogen infection structures, such as lobate appressoria and infection cushions, reduced on the treated plants compared to the control. Plant growth parameters such as dry and wet weight, shoot and root length significantly increased when the tomato seeds were coated with A. jodhpurensis compared to the non-treated control. Among the different coating materials used as sticker, sucrose was found to be the most effective for reducing the disease severity of R. solani and increasing plant growth parameters, which in sucrose, A. jodhpurensis and R. solani treatment the disease index significantly reduced compared to the plants only inoculated with R. solani. Therefore, seed coating using the endophytic fungus A. jodhpurensis supplemented with stickers, particularly edible sucrose, can be applied to protect tomato plants against this destructive pathogen. [ABSTRACT FROM AUTHOR]

Using effluents as a growth medium for microalgae contributes to the effluent treatment and reduces the costs associated with biomass production. Dairy effluent (DE) is among the most voluminous food industry effluents generated. This study aimed to produce biomass and agricultural biostimulants by cultivating Chlorella fusca LEB 111 and Spirulina sp. LEB 18 in dairy effluent. The microalgae were grown in pure and diluted DE at 25%, 50%, and 75% in water and, BG 11 and Zarrouk culture media. The treated DE (culture supernatant) was utilized as a biostimulant in the germination of red pear tomato (Lycopersicon esculentum) seeds. After the cultivation process, treated effluent was obtained with BOD removal efficiency of 98.5% and 99.1%, COD 96.5% and 97.7%, total phosphorus 98.8% and 85.3%, and ammonia nitrogen 98% and 99% for C. fusca LEB 111 and Spirulina sp. LEB 18, respectively. Under the condition in which 100% DE was used, the maximum biomass concentrations of 1.03 g L−1 and 1.98 g L−1 and maximum biomass productivity of 159.70 mg L−1 day−1 and 187.70 mg L−1 day−1 were achieved for Chlorella and Spirulina, respectively. The C. fusca LEB 111 supernatant grown with 100% DE increased seed germination, resulting in 100% germinated seeds. Therefore, this study presents an alternative for microalgae cultivation utilizing DE as an alternative medium, resulting in biomass and treated effluent with high potential for application in agriculture. [ABSTRACT FROM AUTHOR]

Botrytis cinerea is a common pathogenic agent, causing a significant reduction in tomato quality and yield. In this study, the potential of two biocontrol fungal agents, Trichoderma harzianum and Clonostachys rosea to prevent and alleviate B. cinerea infection was assessed. To this end, the fungicidal effects of both biocontrol fungi were evaluated on ten common phytopathogens, including B. cinerea. Then, various ratios of T. harzianum and C. rosea mixtures were assessed to find the ratio that best promotes the growth of tomato seedlings and prevents the establishment of B. cinerea. The results showed that T. harzianum and C. rosea had significant fungicidal effects on all tested phytopathogens. Also, both biocontrol agents reduced the establishment of B. cinerea, in vitro assays, indicating they had significant fungicidal effects against this phytopathogen. However, when applied as a biofungicide to tomato plants, a combination of both biocontrol agents gave better control of B. cinerea. Investigating the molecular basis of resistance to B. cinerea induced by the mixture of T. harzianum and C. rosea revealed that the salicylic acid signaling pathway plays an important role in modulating the antioxidant enzyme activity. Taken together, the results of this research confirmed that both biocontrol fungal agents could induce the mechanism of B. cinerea resistance in tomato plants and shed light on the regulatory pathways associated with the resistance mechanism. [ABSTRACT FROM AUTHOR]

Preharvest fruit rots are serious tomato diseases. This study showed that Botrytis cinerea was a significant problem, and that Alternaria (A. alternata, A. solani) was the main pathogen identified from tomatoes showing the symptoms of preharvest fruit rots. Fusarium oxysporum and Rhizoctonia solani were also found causing important preharvest fruit rots in tomatoes. This is the first time F. oxysporum and R. solani have been identified in Greece as pathogens causing preharvest fruit rots on tomatoes. The optimal temperatures for A. alternata, A. solani, B. cinerea, and F. oxysporum mycelial growth and conidial germination were generally found to be between 20 and 30 °C, while the wetness duration of 24 hours seemed to be optimal for conidial germination and 84 hours for R. solani sclerotial germination. Based on the above findings, logistic regression models that adequately described the impact of pre-inoculation temperature and wetness on infection incidence in tomato fruit can be created. As the minimum, maximum, optimal temperatures and wetness duration are generally similar for the main pathogens causing preharvest fruit rots in tomato, it is possibly to develop a predicting predictive model to forecast the preharvest infection of tomato fruit. So enabling advice to be given to growers to when control methods should be applied. [ABSTRACT FROM AUTHOR]

Cladosporium fulvum is a fungal pathogen that causes leaf mould of tomato. The reference genome of this pathogen was released in 2012 but its high repetitive DNA content prevented a contiguous assembly and further prohibited the analysis of its genome architecture. In this study, we combined third generation sequencing technology with the Hi-C chromatin conformation capture technique, to produce a high-quality and near complete genome assembly and gene annotation of a Race 5 isolate of C. fulvum. The resulting genome assembly contained 67.17 Mb organized into 14 chromosomes (Chr1-to-Chr14), all of which were assembled telomere-to-telomere. The smallest of the chromosomes, Chr14, is only 460 kb in size and contains 25 genes that all encode hypothetical proteins. Notably, PCR assays revealed that Chr14 was absent in 19 out of 24 isolates of a world-wide collection of C. fulvum, indicating that Chr14 is dispensable. Thus, C. fulvum is currently the second species of Capnodiales shown to harbour dispensable chromosomes. The genome of C. fulvum Race 5 is 49.7 % repetitive and contains 14 690 predicted genes with an estimated completeness of 98.9%, currently one of the highest among the Capnodiales. Genome structure analysis revealed a compartmentalized architecture composed of gene-dense and repeat-poor regions interspersed with gene-sparse and repeat-rich regions. Nearly 39.2 % of the C. fulvum Race 5 genome is affected by Repeat-Induced Point (RIP) mutations and evidence of RIP leakage toward non-repetitive regions was observed in all chromosomes, indicating the RIP plays an important role in the evolution of this pathogen. Finally, 345 genes encoding candidate effectors were identified in C. fulvum Race 5, with a significant enrichment of their location in gene-sparse regions, in accordance with the 'two-speed genome' model of evolution. Overall, the new reference genome of C. fulvum presents several notable features and is a valuable resource for studies in plant pathogens.

Abstract Background Arbuscular mycorrhizal fungi (AMF) and Trichoderma harzianum are effective bioagents against Fusarium oxysporum and Verticillium dahliae in tomato plants. The objective of the research was to evaluate the in vivo antagonistic activity of AMF and T. harzianum against Verticillium and Fusarium wilt by enhancing the growth and resistance of tomato plants. A completely randomized experimental design was used, consisting of twelve treatments with nine replicates for each treatment. The treatments included combinations of AMF and T. harzianum inoculation, infection or non-infection by F. oxysporum and V. dahliae, while also considering individual and combined treatments. Mycorrhization rates, growth parameters, disease severity, disease progression, and the impact on disease mitigation were evaluated. Results The study revealed the superiority of AMF over T. harzianum, resulting in a significant enhancement in the overall extent of mycorrhizal colonization in tomato plants co-inoculated with T. harzianum. Moreover, AMF treatments and the AMF + T. harzianum consortium contributed to the improvement in growth among all plants infected with V. dahliae and F. oxysporum. Both AMF and T. harzianum significantly reduced the progression of Fusarium wilt, resulting in reductions of 45.14 and 44.91%, respectively, than the untreated plants infected with F. oxysporum (initial disease severity of 75.54%). T. harzianum demonstrated greater efficacy in reducing V. dahliae infection, with a reduction of 34.45% compared to 28.26% for AMF, starting from an initial disease severity of 69.85%. Thus, T. harzianum demonstrated greater effectiveness in controlling disease, particularly Verticillium wilt. Conclusion The target application of disease control methods in tomato plants revealed the effectiveness of both AMF and T. harzianum in mitigating Fusarium wilt. Furthermore, T. harzianum demonstrated a higher level of effectiveness against Verticillium wilt. These findings emphasize the potential of AMF and T. harzianum as sustainable alternatives in agriculture, providing a viable option to decrease dependence on fungicides.

Osmotically dehydrated cherry tomatoes and spinach leaves were incorporated into Greek salad-type (including OD-treated and air-dried feta cheese trimmings and air-dried olive rings) and green salad-type (including OD-treated and air-dried feta cheese trimmings and roasted ground peanuts) ready-to-eat (RTE) product prototypes, respectively. The osmotic dehydration of cherry tomatoes and spinach leaves was conducted in a pilot scale setting (100 L) in a 60% glycerol-based solution at 35 °C and 25 °C for 180 min and 60 min, respectively. To quantify the moisture transfer between the three ingredients of different moisture content (and water activity), the moisture equilibrium curves for each ingredient of the RTE product were determined. The equilibrium water activity of RTE products was 0.86 and 0.76, respectively. The quality of the RTE products (more specifically, tomato and spinach color and texture, instrumentally measured and sensorially perceived, sensory characteristics) was evaluated. The shelf life of the prototypes (from 4 °C to 20 °C) was kinetically modeled based on sensory deterioration and microbial growth, using the zero-order kinetic model and the Gompertz model, respectively. In the case of the tomato-based product, a shelf life of 54 days (based on sensory deterioration) was achieved at 4 °C, a shelf-life extension of 40 days compared to untreated, fresh-cut tomato. The shelf life of the spinach-based product (based on sensory deterioration) was 36 days at 4 °C, 30 days longer when compared to untreated spinach. Our results indicate that osmotic dehydration was successful in significantly extending the shelf life of such products, contributing to the increased temperature resilience of their keeping quality and allowing for their distribution and storage in a variable cold chain.

Agriculture has a significant environmental impact and is simultaneously called to major challenges, such as responding to the need to develop more sustainable cropping systems with higher productivity. In this context, the present study aimed to obtain lignin nanoparticles (LNs) from pomace, a waste product of the olive oil chain, to be used as a nanobiostimulant in tomato plants. The biostimulant effect of this biopolymer is known, but its reduction to nanometer size can emphasize this property. Tomato plants were subjected to different LN dosages (25, 50, and 100 mg L−1) by foliar application, and inductive effects on photosynthetic machinery, aerial and root biomass production, and root morphology were observed. The treated plants showed increased efficiency in catching and using light, while they reduced the fraction dissipated as heat or potentially toxic to cells for the possibility of creating reactive oxygen species (ROS). Finally, this benefit was matched by increased pigment content and a stimulatory action on the content of nitrogen (NBI) and antioxidant substances such as flavonoids. In conclusion, the present study broadens the horizon of substances with biostimulant action by demonstrating the validity and efficacy of nanobiostimulants obtained from biological residues from the olive oil production chain.

Agricultural systems must improve their sustainability and productivity to meet the growing global demand for food. A cost-effective and sustainable way is the development of biostimulants from plants rich in bioactive compounds. This study aimed to test an aqueous extract from Lemna minor L. (duckweed) on tomato plants at different concentrations (LE—0.1, 0.5 and 1.0%—weight/volume, w/v). Photosystem I and II activity, linear electron flow (LEF), electrochemical gradient across the thylakoid membrane (ECSt), shoot biomass production, root phenotyping, pigment and metabolite content were studied. LE improved many of these traits, with LE 0.5% being the most effective dosage. Compared to the untreated samples, LE significantly stimulated photosystems to use light energy while reducing the amount lost as heat (PhiNPQ and NPQt) or potentially toxic to chloroplasts (PhiNO). These results were supported by the improved shoot biomass production (number of leaves and fresh and dry weight) and root traits (number of tips, surface, volume and fresh and dry weight) found for LE-treated samples compared to untreated controls. Finally, the study highlighted that LE increased pigment and flavonoid contents. In conclusion, the research indicates that this species can be an effective and eco-friendly tool to stimulate beneficial responses in tomato.

Copper (Cu) is the most extensively used bactericide worldwide in many agricultural production systems. However, intensive application of Cu bactericide have increased the selection pressure toward Cu-tolerant pathogens, including Xanthomonas perforans, the causal agent of tomato bacterial spot. However, alternatives for Cu bactericides are limited and have many drawbacks including plant damage and inconsistent effectiveness under field conditions. Also, potential ecological risk on nontarget organisms exposed to field runoff containing Cu is high. However, due to lack of alternatives for Cu, it is still widely used in tomato and other crops around the world in both conventional and organic production systems. In this study, a Cu-tolerant X. perforans strain GEV485, which can tolerate eight tested commercial Cu bactericides, was used in all the field trials to evaluate the efficacy of MgO nanomaterial. Four field experiments were conducted to evaluate the impact of intensive application of MgO nanomaterial on tomato bacterial spot disease severity, and one field experiment was conducted to study the impact of soil accumulation of total and bioavailable Cu, Mg, Mn, and Zn. In the first two field experiments, twice-weekly applications of 200 μg/mL MgO significantly reduced disease severity by 29-38% less in comparison to a conventional Cu bactericide Kocide 3000 and 19-30% less in comparison to the water control applied at the same frequency (p = 0.05). The disease severity on MgO twice-weekly was 12-32% less than Kocide 3000 + Mancozeb treatment. Single weekly applications of MgO had 13-19% higher disease severity than twice weekly application of MgO. In the second set of two field trials, twice-weekly applications of MgO at 1000 μg/mL significantly reduced disease severity by 32-40% in comparison to water control applied at the same frequency (p = 0.05). There was no negative yield impact in any of the trials. The third field experiment demonstrated that application of MgO did not result in significant accumulation of total and bioavailable Mg, Mn, Cu, or Zn in the root-associated soil and in soil farther away from the production bed compared to the water control. However, Cu bactericide contributed to significantly higher Mn, Cu, and Zn accumulation in the soil compared to water control (p = 0.05). This study demonstrates that MgO nanomaterial could be an alternative for Cu bactericide and have potential in reducing risks associated with development of tolerant strains and for reducing Cu load in the environment.

This study explores the osmotic dehydration (OD) of fresh-cut cherry tomatoes through the application of Pulsed Electric Fields (PEF) and High-Pressure (HP) pre-treatments. Untreated, PEF-treated (1.8 kV/cm, 0–300 pulses), and HP-treated (0–600 MPa, 5 min) tomatoes were subjected to osmotic dehydration at 35 °C for up to 3 h. The results reveal that a 100-pulse PEF treatment and HP treatment at 600 MPa yielded optimal outcomes in terms of both OD enhancement (with effective moisture diffusion coefficients of 7.91 · 10−10 m2/s for PEF and 7.40 · 10−10 m2/s for HP-treated tomatoes compared to 5.17 · 10−10 m2/s for untreated samples) and product acceptability (achieving overall acceptance scores between 7 and 8). Applying PEF (100 pulses) and HP (600 MPa) pre-treatments reduced the water activity (aw) to 0.887 and 0.760, respectively, after 3 h of OD, compared to aw = 0.923 for untreated OD samples. The selection of these pre-treatment conditions enabled effective dehydration and quality retention, extending the shelf life by up to 40 days under chilled storage. [ABSTRACT FROM AUTHOR]

Background and Objectives: Plant growth-promoting bacteria (PGPB) may reduce the negative effects of salinity stress. The aim of this study was to optimize Bacillus megaterium RTS1 and characterize the effect of the PGPB on the physiological characteristics of tomato (Lycopersicon esculentum). Materials and Methods: The Central composite design (CCD) of response surface methodology (RSM) was used to optimize Bacillus megaterium RTS1 to produce maximum cell biomass and spores. Then the effect of the PGPB on the physiological characteristics of tomato (Lycopersicon esculentum), including membrane stability, leaf relative water content percentage, anthocyanin and carotenoids content, chlorophyll photosynthetic parameters, sugar and starch level, superoxide anion and antioxidant activity under salt stress conditions. The NFB medium was inoculated with 5% bacterial culture and the fermentation was carried out in a 10-lit fermenter. Results: After optimization, the amount of cell biomass by the model was 9.45 log10 CFUs/mL, which showed a 1.2-fold increase compared to the non-optimized medium. Usage of bacteria under the optimal conditions of the culture medium may increase the stability of the membrane and improve the relative water content. Bacteria were able to prevent the excessive increase of anthocyanins. Oxidative stress led to an increase in the content of chlorophyll a, while causing the degradation of chlorophyll b. Bacterial inoculation led to an increase in the level of sugar and starch compared to the control. PGPB showed an increasing effect on the amount of superoxide anion production and caused a significant increase in the antioxidant activity under salinity stress conditions. Conclusion: The PGPB can be a promising way to boost physiological characteristics of tomato plant under salinity stress. Also, sporulation capacity of Bacillus megaterium with high bacterial cell density in fermenter produce a sustainable product for tomato plants. [ABSTRACT FROM AUTHOR]

Background: Arbuscular mycorrhizal fungi (AMF) and Trichoderma harzianum are effective bioagents against Fusarium oxysporum and Verticillium dahliae in tomato plants. The objective of the research was to evaluate the in vivo antagonistic activity of AMF and T. harzianum against Verticillium and Fusarium wilt by enhancing the growth and resistance of tomato plants. A completely randomized experimental design was used, consisting of twelve treatments with nine replicates for each treatment. The treatments included combinations of AMF and T. harzianum inoculation, infection or non-infection by F. oxysporum and V. dahliae, while also considering individual and combined treatments. Mycorrhization rates, growth parameters, disease severity, disease progression, and the impact on disease mitigation were evaluated. Results: The study revealed the superiority of AMF over T. harzianum, resulting in a significant enhancement in the overall extent of mycorrhizal colonization in tomato plants co-inoculated with T. harzianum. Moreover, AMF treatments and the AMF + T. harzianum consortium contributed to the improvement in growth among all plants infected with V. dahliae and F. oxysporum. Both AMF and T. harzianum significantly reduced the progression of Fusarium wilt, resulting in reductions of 45.14 and 44.91%, respectively, than the untreated plants infected with F. oxysporum (initial disease severity of 75.54%). T. harzianum demonstrated greater efficacy in reducing V. dahliae infection, with a reduction of 34.45% compared to 28.26% for AMF, starting from an initial disease severity of 69.85%. Thus, T. harzianum demonstrated greater effectiveness in controlling disease, particularly Verticillium wilt. Conclusion: The target application of disease control methods in tomato plants revealed the effectiveness of both AMF and T. harzianum in mitigating Fusarium wilt. Furthermore, T. harzianum demonstrated a higher level of effectiveness against Verticillium wilt. These findings emphasize the potential of AMF and T. harzianum as sustainable alternatives in agriculture, providing a viable option to decrease dependence on fungicides. [ABSTRACT FROM AUTHOR]

In greenhouse and field trials, a bacterial mixture of Collimonas arenae Cal35 and Bacillus velezensis FZB42, but not Cal35 alone or FZB42 alone, was able to protect tomato plants from challenge with the soilborne fungal pathogen Fusarium oxysporum f.sp. lycopersici (Fol). To identify genes and mechanisms underlying this property in Cal35, we screened a random transposon insertion library for loss of function and identified two mutants that were impaired completely or partially in their ability to halt the growth of a wide range of fungal species. In mutant 46A06, the transposon insertion was located in a biosynthetic gene cluster that was predicted to code for a hybrid polyketide synthase-non-ribosomal peptide synthetase, while mutant 60C09 was impacted in a gene cluster for the synthesis and secretion of sugar repeat units. Our data are consistent with a model in which both gene clusters are necessary for the production of an antifungal compound we refer to as carenaemins. We also show that the ability to produce carenaemin contributed significantly to the observed synergy between Cal35 and FZB42 in protecting tomato plants from Fol. We discuss the potential for supplementing Bacillus-based biocontrol products with Collimonas bacteria to boost efficacy of such products.

The increased susceptibility of ripe fruit to fungal pathogens poses a substantial threat to crop production and marketability. Here, we coupled transcriptomic analyses with mutant studies to uncover critical processes associated with defense and susceptibility in tomato (Solanum lycopersicum) fruit. Using unripe and ripe fruit inoculated with three fungal pathogens, we identified common pathogen responses reliant on chitinases, WRKY transcription factors, and reactive oxygen species detoxification. We established that the magnitude and diversity of defense responses do not significantly impact the interaction outcome, as susceptible ripe fruit mounted a strong immune response to pathogen infection. Then, to distinguish features of ripening that may be responsible for susceptibility, we utilized non-ripening tomato mutants that displayed different susceptibility patterns to fungal infection. Based on transcriptional and hormone profiling, susceptible tomato genotypes had losses in the maintenance of cellular redox homeostasis, while jasmonic acid accumulation and signaling coincided with defense activation in resistant fruit. We identified and validated a susceptibility factor, pectate lyase (PL). CRISPR-based knockouts of PL, but not polygalacturonase (PG2a), reduced susceptibility of ripe fruit by >50%. This study suggests that targeting specific genes that promote susceptibility is a viable strategy to improve the resistance of tomato fruit against fungal disease.

Leaf morphogenesis involves cell division, expansion, and differentiation in the developing leaf, which take place at different rates and at different positions along the medio-lateral and proximal-distal leaf axes. The gene expression changes that control cell fate along these axes remain elusive due to difficulties in precisely isolating tissues. Here, we combined rigorous early leaf characterization, laser capture microdissection, and transcriptomic sequencing to ask how gene expression patterns regulate early leaf morphogenesis in wild-type tomato (Solanum lycopersicum) and the leaf morphogenesis mutant trifoliate. We observed transcriptional regulation of cell differentiation along the proximal-distal axis and identified molecular signatures delineating the classically defined marginal meristem/blastozone region during early leaf development. We describe the role of endoreduplication during leaf development, when and where leaf cells first achieve photosynthetic competency, and the regulation of auxin transport and signaling along the leaf axes. Knockout mutants of BLADE-ON-PETIOLE2 exhibited ectopic shoot apical meristem formation on leaves, highlighting the role of this gene in regulating margin tissue identity. We mapped gene expression signatures in specific leaf domains and evaluated the role of each domain in conferring indeterminacy and permitting blade outgrowth. Finally, we generated a global gene expression atlas of the early developing compound leaf.

Background and Objectives: Plant growth-promoting bacteria (PGPB) may reduce the negative effects of salinity stress. The aim of this study was to optimize Bacillus megaterium RTS1 and characterize the effect of the PGPB on the physiological characteristics of tomato (Lycopersicon esculentum). Materials and Methods: The Central composite design (CCD) of response surface methodology (RSM) was used to optimize Bacillus megaterium RTS1 to produce maximum cell biomass and spores. Then the effect of the PGPB on the physiological characteristics of tomato (Lycopersicon esculentum), including membrane stability, leaf relative water content percentage, anthocyanin and carotenoids content, chlorophyll photosynthetic parameters, sugar and starch level, superoxide anion and antioxidant activity under salt stress conditions. The NFB medium was inoculated with 5% bacterial culture and the fermentation was carried out in a 10-lit fermenter. Results: After optimization, the amount of cell biomass by the model was 9.45 log10 CFUs/mL, which showed a 1.2-fold increase compared to the non-optimized medium. Usage of bacteria under the optimal conditions of the culture medium may increase the stability of the membrane and improve the relative water content. Bacteria were able to prevent the excessive increase of anthocyanins. Oxidative stress led to an increase in the content of chlorophyll a, while causing the degradation of chlorophyll b. Bacterial inoculation led to an increase in the level of sugar and starch compared to the control. PGPB showed an increasing effect on the amount of superoxide anion production and caused a significant increase in the antioxidant activity under salinity stress conditions. Conclusion: The PGPB can be a promising way to boost physiological characteristics of tomato plant under salinity stress. Also, sporulation capacity of Bacillus megaterium with high bacterial cell density in fermenter produce a sustainable product for tomato plants.

Increasing scarcity and unreliability of rainfall, and the absence of irrigation schedules are challenges to decision-making, particularly for viable tomato (Lycopersicon esculentum Mill) production in Zimbabwe. The objective of this study was to determine water requirements of tomato as a basis for developing generic calendar guidelines for a more efficient irrigation management in Harare, Zimbabwe. We explored the options of improving the traditional, dry and supplementary wet season irrigation practices. By considering the archived climate data of thirty years (1991-2021) for Harare; and modelsimulated consumptive water use from 2014 to 2017 at Thornpark Research Station, together with the crop and soil characteristics; and the irrigation method; an irrigation calendar was developed using the AquaCrop model 5.0. The improved irrigation schedule for dry season tomato cultivation at 60% ETc, resulted in water use of 471.6 mm, with a yield of 3.40 t ha-1; compared to water use of 820 mm and a yield of 1.118 t ha-1; for the wet season. Through this model, we have been able to estimate the time interval between the previous irrigation and the next irrigation for any date in the growing season. Therefore, year-round irrigated tomato production may be feasible with an added yield advantage of 2.28 t ha-1 obtainable using water and rainy periods. [ABSTRACT FROM AUTHOR]

Abstract Tomato pomace, a waste product consisting of peels, seeds, rich on fibrous matter, represents an underutilized source of bioactive compounds, such as polyphenols and carotenoids. Here we present a three-pronged review of the circular utilization of tomato waste in line with the United Nations Sustainable Development Goals. First, we explain why tomato waste is important, highlighting the processing techniques that generate it. The bioactive compounds in these by-products are then comprehensively reviewed, focusing especially on phenolic compounds and carotenoids and the methods used for their extraction. Finally, we examine the potential of these bioactive ingredients for application in food systems and pharmaceutical products. [ABSTRACT FROM AUTHOR]

Background and aims: The plant growth promoting rhizobacteria have been repeatedly addressed in improving plant growth and resistance against pathogens. This study explored the role of Paraburkholderia sp. GD17 in improving tomato plant growth and resistance to Botrytis cinerea (Bc). Methods: Tomato roots were treated with GD17 strain, and then the leaves were inoculated with Bc. Physiological and biochemical parameters, and gene expression were analyzed. Results: In the absence of Bc, GD17 efficiently improved plant growth, and increased photosynthetic efficiency. In the presence of Bc, GD17-bacterized plants exhibited an enhanced resistance, as indicated by 67% of disease index in non-bacterized plants, while by 24% in bacterized ones. In response to Bc, the defense reaction was reinforced in bacterized plants, as shown by enhanced antioxidative capacity and mitigated oxidative damage, as well as increased PR gene expression in bacterized plants compared with control. Photosynthesis was inhibited by Bc inoculation, to a greater degree in non-bacterized plants than in bacterized ones. In the presence of Bc, soluble sugar contents significantly increased in non-bacterized plants, while it was controlled in bacterized plants. The carbohydrate catabolism-related genes, including starch degradation, photorespiration, and pentose phosphate pathway, generally presented a higher expression in bacterized plants under Bc attack. Conclusions: GD17 strain improved tomato plant growth by increasing the photosynthetic efficiency. GD17 enhanced plant resistance against Bc-induced disease by increasing defense and alleviating oxidative damage. Additionally, GD17 optimized the trade-off between plant growth and defense by strengthening carbohydrate metabolic regulation. [ABSTRACT FROM AUTHOR]

The oomycete Phytophthora infestans, the causal agent of potato and tomato blight, expresses two extracellular invertases. Unlike typical fungal invertases, the P. infestans genes are not sucrose induced or glucose repressed but instead appear to be under developmental control. Transcript levels of both genes were very low in mycelia harvested from artificial medium but high in preinfection stages (sporangia, zoospores, and germinated cysts), high during biotrophic growth in leaves and tubers, and low during necrotrophy. Genome-wide analyses of metabolic enzymes and effectors indicated that this expression profile was fairly unusual, matched only by a few other enzymes, such as carbonic anhydrases and a few RXLR effectors. Genes for other metabolic enzymes were typically downregulated in the preinfection stages. Overall metabolic gene expression during the necrotrophic stage of infection clustered with artificial medium, while the biotrophic phase formed a separate cluster. Confocal microscopy of transformants expressing green fluorescent protein (GFP) fusions indicated that invertase protein resided primarily in haustoria during infection. This localization was not attributable to haustorium-specific promoter activity. Instead, the N-terminal regions of proteins containing signal peptides were sufficient to deliver proteins to haustoria. Invertase expression during leaf infection was linked to a decline in apoplastic sucrose, consistent with a role of the enzymes in plant pathogenesis. This was also suggested by the discovery that invertase genes occur across multiple orders of oomycetes but not in most animal pathogens or a mycoparasite.IMPORTANCE Oomycetes cause hundreds of diseases in economically and environmentally significant plants. How these microbes acquire host nutrients is not well understood. Many oomycetes insert specialized hyphae called haustoria into plant cells, but unlike their fungal counterparts, a role in nutrition has remained unproven. The discovery that Phytophthora invertases localize to haustoria provides the first strong evidence that these structures participate in feeding. Since regions of proteins containing signal peptides targeted proteins to the haustorium-plant interface, haustoria appear to be the primary machinery for secreting proteins during biotrophic pathogenesis. Although oomycete invertases were acquired laterally from fungi, their expression patterns have adapted to the Phytophthora lifestyle by abandoning substrate-level regulation in favor of developmental control, allowing the enzymes to be produced in anticipation of plant colonization. This study highlights how a widely distributed hydrolytic enzyme has evolved new behaviors in oomycetes.

Reduced insect pest populations found on long-term organic farms have mostly been attributed to increased biodiversity and abundance of beneficial predators, as well as to changes in plant nutrient content. However, the role of plant resistance has largely been ignored. Here, we determine whether host plant resistance mediates decreased pest populations in organic systems and identify potential underpinning mechanisms. We demonstrate that fewer numbers of leafhoppers (Circulifer tenellus) settle on tomatoes (Solanum lycopersicum) grown using organic management as compared to conventional. We present multiple lines of evidence, including rhizosphere soil microbiome sequencing, chemical analysis and transgenic approaches, to demonstrate that changes in leafhopper settling between organically and conventionally grown tomatoes are dependent on salicylic acid accumulation in plants and mediated by rhizosphere microbial communities. These results suggest that organically managed soils and microbial communities may play an unappreciated role in reducing plant attractiveness to pests by increasing plant resistance.

There is increasing interest in the plant microbiome as it relates to both plant health and agricultural sustainability. One key unanswered question is whether we can select for a plant microbiome that is robust after colonization of target hosts. We used a successive passaging experiment to address this question by selecting upon the tomato phyllosphere microbiome. Beginning with a diverse microbial community generated from field-grown tomato plants, we inoculated replicate plants across 5 plant genotypes for 4 45-d passages, sequencing the microbial community at each passage. We observed consistent shifts in both the bacterial (16S amplicon sequencing) and fungal (internal transcribed spacer region amplicon sequencing) communities across replicate lines over time, as well as a general loss of diversity over the course of the experiment, suggesting that much of the naturally observed microbial community in the phyllosphere is likely transient or poorly adapted within the experimental setting. We found that both host genotype and environment shape microbial composition, but the relative importance of genotype declines through time. Furthermore, using a community coalescence experiment, we found that the bacterial community from the end of the experiment was robust to invasion by the starting bacterial community. These results highlight that selecting for a stable microbiome that is well adapted to a particular host environment is indeed possible, emphasizing the great potential of this approach in agriculture and beyond. In light of the consistent response of the microbiome to selection in the absence of reciprocal host evolution (coevolution) described here, future studies should address how such adaptation influences host health.

Lead is a harmful pollutant from engine exhaust that causes free radicals and has detrimental effects on the testicular tissue. This study aimed to determine the effects of tomato juice on the number of Leydig cells and the diameter of the seminiferous tubules of mice exposed to lead acetate. Twenty-five male mice were divided into five groups. Mice in the control (C-) group were given placebos. Meanwhile, mice in C+, T1, T2, and T3 groups were exposed to lead acetate at a dose of 100 mg/kg BW/day for 14 days and given tomato juice respectively at 0, 0.16, 0.32, and 0.64 mL/day from day 8 to day 35. On day 36, all mice were sacrificed, and the testes were collected for histological preparation. The result showed that lead exposure in the C+ group decreased (p

The aim of this research is to determine the physiological responses of tomato seedlings treated with 24-epibrassinolide (EBL), given via different methods such as immersion, irrigation, and foliar spray, followed by inoculation of root-knot nematode Meloidogyne incognita (Kofoid & White 1919) Chitwood, 1949 (Tylenchida: Meloidogynidae). Physiological measurements (chlorophyll, flavonols, nitrogen balance index, and anthocyanins) were carried out non-destructively with a portable chlorophyll meter at the end of the 56th days post inoculation. Results showed that chlorophyll contents of the tomato leaves were affected by both the EBL applications and the methods. Chlorophyll contents were better protected with the irrigation method. Flavonols and nitrogen balance index were inversely related with the application method. Leaf anthocyanin index was affected just by the EBL applications. Depending on the physiological aspect under observation, the method (immersion against irrigation, for instance) might present a challenging status in terms of providing protection against root-knot nematode when tomato plants are treated with EBL.

During the summer months, greenhouse tomato production is challenged by the heat, causing yield reduction; therefore, we conducted a study to test the effectiveness of different foliar spray compositions for the improvement of Lycopersicon esculentum var. cerasiforme ‘Qianxi’ nutrition uptake and fruit yield. Two forms of silicon, two kinds of organic nitrogenous compounds and water as the control factor were two-two paired to become nine different recipes, which were as follows: CK (H2O), ISi (K2SiO3), organic silicon (OSi), potassium fulvate (BSFA), BSFA + ISi, BSFA + OSi, betaine (GB), GB + ISi and GB + OSi. The plants were sprayed three times during the period of the first, second and third truss fruit expansions with a 2-week interval. As a result, BSFA or K2SiO3 generated higher yield in plants compared with the other compositions. Also, K2SiO3 significantly enhanced the total nitrogen, phosphorus and potassium accumulation in fruit and the whole plant. Comparing across the nine recipes, BSFA + ISi, ISi and GB had improved the fruit yield by 17%, 12.7% and 9.5%, performing the best. BSFA + ISi, ISi and GB also improved the plant nitrogen uptake by 8.2%, 18.8% and 9.8%, as well as the potassium uptake by 16.2%, 12.3% and 15.2%, compared with CK, respectively. Thus, K2SiO3, BSFA and GB stimulated the plant nitrogen and potassium uptake, which improved the marketable yield.

Nutrient solution pH and water quality are challenges faced by small-scale hydroponic growers. The objective was to evaluate the use of the pH buffer 2-(N-morpholino) ethanesulfonic acid (MES) as an initial dose to simplify pH management in small-scale hydroponic systems, and its effectiveness within the range of alkalinity that commonly occurs in irrigation water. Two experiments tested pH buffering capacity in response to acid-base titrations, and when growing compact tomatoes (Lycopersicon esculentum) over a nine-week cycle. MES was applied at 0 to 10 mM in water and nutrient solutions at five water qualities ranging from 4 to 295 mg.L−1 CaCO3 alkalinity. Solution buffering increased with addition of fertilizer, increasing doses of MES, and increasing water alkalinity. The MES decreased pH variability over time in all water qualities, without affecting plant growth or causing nutritional disorders. The pH of solutions without MES ranged from 4.5 to 8.0 over the growing cycle, whereas in 10 mM MES solutions it ranged from 5.7 to 7.0 for alkalinities 0 to 146 mg.L−1 CaCO3 and reached 7.6 for 295 mg.L−1 CaCO3. Titration of nutrient solutions after tomato growth indicates that MES acid-buffering capacity was partially consumed along the trial, which was probably the result of MES decomposition or interaction with acids and bases in solution. Results indicate that a single 10 mM MES application could be used by small-scale hydroponic growers to provide acceptable pH buffering for low to moderate alkalinity levels, but initial pH adjustment may be necessary and solution pH may still increase with high alkalinity. [ABSTRACT FROM AUTHOR]

Although sewage water (SW) is a source of nutrients, it also causes heavy metal accumulation in soil; especially, lead (Pb+) contamination of soil is a serious concern in agriculture. Soil contaminants limit the bioavailability of nutrients to plants. So, they affect plant growth and produce quality. Therefore, a pot experiment was conducted to investigate the effect of zeolite soil amendment on the accumulation of Pb+ in tomato crop grown with SW irrigation. The pot media of SW-irrigated plants was amended with different concentrations of zeolite, viz., 0.75%, 1.50%, and 2.25%. The results showed that the application of 0.75% zeolite increased leaf area, plant height, fruit number, and plant fresh and dry biomasses by 37%, 17%, 14%, 24%, and 7% compared to freshwater irrigation. Moreover, the lowest zeolite dose also led to higher chlorophyll content (68.02 SPAD) compared to SW-irrigated plants (55.13 SPAD). Similarly physiological traits, such as A, gs, and E, were higher (17.68 µmol m−2 s−1, gs 0.28 mmol m−2 s−1, and 7.88 mmol m−2 s−1, respectively) in 0.75% zeolite-treated plants than in SW-irrigated plants (12.99 µmol m−2 s −1, 0.19 mmol m−2 s−1, and 7.00 mmol m−2 s −1, respectively). On the contrary, a reduced level of hydrogen peroxide and malondialdehyde and decreased activity of antioxidant enzymes were observed in low-dose zeolite applied plants. Zeolite reduced Pb+ accumulation in tomato plants as compared to SW-irrigated plants, whereby Pb accumulation in the fruits of SW-irrigated plants was 80% more than those of zeolite + SW–treated plants. Conclusively, this study has revealed the improvement in morphological and physiological growth attributes of the SW-irrigated tomato plant in response to zeolite application. [ABSTRACT FROM AUTHOR]

In this study, the content of lead (Pb), cadmium (Cd), chromium (Cr) and manganese (Mn) was evaluated in soils and tomatoes (Lycopersicon esculentum) collected from rural areas of Dobrogea province, South-East of Romania. The risk to human health due to the heavy metal exposure via tomato consumption was also assessed. The results suggest that based on the contamination factor, the soils are moderately contaminated with Cd and Mn (Cf values of 1.266. and 1.40) and poorly contaminated with Pb and Cr. The bioconcentration factor (BAF) was below 1 and indicated that the studied species of Lycopersicon esculentum did not accumulate the monitored elements. Person's correlation analysis showed that there were significant relations between soil pH and BCF values of Cd, Pb, Cr and Mn in analysed tomatoes. The estimated daily intake of each metal was below the oral reference dose. The hazard quotient (HQ) and hazard index (HI) were below the acceptable level (< 1), and the cancer risk (CR) for Pb, Cd and Cr was found within acceptable levels (1.0 × 10−6–1.0 × 10−4). Based on health guidance values, it may be concluded that the analysed tomatoes do not present health risks to consumers in terms of content and accumulation of heavy metals. It is important to monitor the other toxic metals as well, in order to evaluate the heavy metal accumulation variation and the toxicity value of each metal in agricultural soils from both rural and industrial areas. [ABSTRACT FROM AUTHOR]

Broomrapes (Phelipanche aegyptiaca and Orobanche spp.) are obligate plant parasites that cause extreme damage to crop plants. The parasite seeds have strict requirements for germination, involving preconditioning and exposure to specific chemicals strigolactones [SLs] exuded by the host roots. SLs are plant hormones derived from plant carotenoids via a pathway involving the Carotenoid Cleavage Dioxygenase 8 (CCD8). Having no effective means to control parasitic weeds in most crops, and with CRISPR/Cas9 being an effective gene-editing tool, here we demonstrate that CRISPR/Cas9-mediated mutagenesis of the CCD8 gene can be used to develop host resistance to the parasitic weed P. aegyptiaca. Cas9/single guide (sg) RNA constructs were targeted to the second exon of CCD8 in tomato (Solanum lycopersicum L.) plants. Several CCD8Cas9 mutated tomato lines with variable insertions or deletions in CCD8 were obtained with no identified off-targets. Genotype analysis of T1 plants showed that the introduced CCD8 mutations are inherited. Compared to control tomato plants, the CCD8Cas9 mutant had morphological changes that included dwarfing, excessive shoot branching and adventitious root formation. In addition, SL-deficient CCD8Cas9 mutants showed a significant reduction in parasite infestation compared to non-mutated tomato plants. In the CCD8Cas9 mutated lines, orobanchol (SL) content was significantly reduced but total carotenoids level and expression of genes related to carotenoid biosynthesis were increased, as compared to control plants. Taking into account, the impact of plant parasitic weeds on agriculture and difficulty to constitute efficient control methods, the current study offers insights into the development of a new, efficient method that could be combined with various collections of resistant tomato rootstocks.

Soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs) are conserved in fungi, plants and animals. The Vam7 gene encodes a v-SNARE protein that involved in vesicle trafficking in fungi. Here, we identified and characterized the function of FolVam7, a homologue of the yeast SNARE protein Vam7p in Fusarium oxysporum f. sp. lycopersici (Fol), a fungal pathogen of tomato. FolVam7 contains SNARE and PX (Phox homology) domains that are indispensable for normal localization and function of FolVam7. Targeted gene deletion showed that FolVam7-mediated vesicle trafficking is important for vegetative growth, asexual development, conidial morphology and plant infection. Further cytological examinations revealed that FolVam7 is localized to vesicles and vacuole membranes in the hyphae stage. Moreover, the ΔFolvam7 mutant is insensitive to salt and osmotic stresses and hypersensitive to cell wall stressors. Taken together, our results suggested that FolVam7-mediated vesicle trafficking promotes vegetative growth, conidiogenesis and pathogenicity of Fol.

Acylsugars have been shown to provide activity against numerous insect pests of tomatoes. Comparison of acylsugar levels in four tomato plant lines, FA7/AS, FA2/AS, CU071026, and 'Yellow Pear', found that the acylsugar contents in the elevated acylsugar lines were significantly higher than the commercial Yellow Pear (control) tomato plant line. Adult choice tests indicated that the tomato psyllid, Bactericera cockerelli, preferred to settle on the Yellow Pear and FA2/AS lines over the line with the highest content of acylsugars, FA7/AS, and the parental line, CU071026. The no-choice test demonstrated that adults laid fewer eggs on the high acylsugar tomato lines than on the control tomato line, Yellow Pear. For all high acylsugar lines, the relative growth index of the psyllid was significantly lower compared with the commercial line, indicating a reduced potential for population growth. Although some tomato psyllids completed their life cycle on the high acylsugar tomato plant lines, the percent survival of psyllids to the adult stage when developing on the high acylsugar lines was significantly less (range = 43.7-57.1%) than on the commercial tomato line (83.8%). All mortality occurred during the early stages of development (egg stage to third instar), which has implications for acquisition and transmission of Candidatus Liberibacter solanacearum, the causal agent of tomato vein greening disease. Therefore, with reduced attractiveness for tomato psyllids and significantly reduced survival, the high-acylsugar tomato plant lines have the potential to be part of an integrated pest management program for this pest.

Agricultural management practices affect bulk soil microbial communities and the functions they carry out, but it remains unclear how these effects extend to the rhizosphere in different agroecosystem contexts. Given close linkages between rhizosphere processes and plant nutrition and productivity, understanding how management practices impact this critical zone is of great importance to optimize plant-soil interactions for agricultural sustainability. A comparison of six paired conventional-organic processing tomato farms was conducted to investigate relationships between management, soil physicochemical parameters, and rhizosphere microbial community composition and functions. Organically managed fields were higher in soil total N and NO3-N, total and labile C, plant Ca, S, and Cu, and other essential nutrients, while soil pH was higher in conventionally managed fields. Differential abundance, indicator species, and random forest analyses of rhizosphere communities revealed compositional differences between organic and conventional systems and identified management-specific microbial taxa. Phylogeny-based trait prediction showed that these differences translated into more abundant pathogenesis-related gene functions in conventional systems. Structural equation modeling revealed a greater effect of soil biological communities than physicochemical parameters on plant outcomes. These results highlight the importance of rhizosphere-specific studies, as plant selection likely interacts with management in regulating microbial communities and functions that impact agricultural productivity.IMPORTANCE Agriculture relies, in part, on close linkages between plants and the microorganisms that live in association with plant roots. These rhizosphere bacteria and fungi are distinct from microbial communities found in the rest of the soil and are even more important to plant nutrient uptake and health. Evidence from field studies shows that agricultural management practices such as fertilization and tillage shape microbial communities in bulk soil, but little is known about how these practices affect the rhizosphere. We investigated how agricultural management affects plant-soil-microbe interactions by comparing soil physical and chemical properties, plant nutrients, and rhizosphere microbial communities from paired fields under organic and conventional management. Our results show that human management effects extend even to microorganisms living in close association with plant roots and highlight the importance of these bacteria and fungi to crop nutrition and productivity.

Burkholderia cenocepacia TAtl-371 was isolated from the rhizosphere of a tomato plant growing in Atlatlahucan, Morelos, Mexico. This strain exhibited a broad antimicrobial spectrum against bacteria, yeast, and fungi. Here, we report and describe the improved, high-quality permanent draft genome of B. cenocepacia TAtl-371, which was sequenced using a combination of PacBio RS and PacBio RS II sequencing methods. The 7,496,106 bp genome of the TAtl-371 strain is arranged in three scaffolds, contains 6722 protein-coding genes, and 99 RNA only-encoding genes. Genome analysis revealed genes related to biosynthesis of antimicrobials such as non-ribosomal peptides, siderophores, chitinases, and bacteriocins. Moreover, analysis of bacterial growth on different carbon and nitrogen sources shows that the strain retains its antimicrobial ability.

Plant intracellular nucleotide binding leucine-rich repeat (NLR) immune receptors play critical roles in pathogen surveillance. Most plant NLRs characterized so far were found to use a single domain/sensor to recognize pathogen effectors. Here we report that the Sw-5b NLR immune receptor uses two distinct domains to detect the viral movement protein NSm encoded by tospovirus. In addition to its leucine-rich repeat (LRR) domain that has been previously reported, the N-terminal Solanaceae domain (SD) of Sw-5b also interacts with NSm and a conserved 21-amino-acid region of NSm (NSm21). The specific interaction between Sw-5b SD and NSm is required for releasing the inhibitory effect of coiled-coil domain on the NB-ARC-LRR region. Furthermore, we found that the binding of NSm affects the nucleotide binding activity of the NB-ARC-LRR in vitro, while Sw-5b NB-ARC-LRR is activated only when NSm and NSm21 levels are high. Interestingly, Sw-5b SD could significantly enhance the ability of the NB-ARC-LRR to detect low levels of NSm effector and facilitate its activation and induction of defense response. An Sw-5b SD mutant that is disrupted in NSm recognition failed to enhance the ability of the NB-ARC-LRR to sense low levels of NSm and NSm21. Taken together, our results suggest that Sw-5b SD functions as an extra sensor and the NB-ARC-LRR as an activator, and that Sw-5b NLR adopts a two-step recognition mechanism to enhance viral effector perception.

The identification and understanding of metabolic pathways is a key aspect in crop improvement and drug design. The common approach for their detection is based on gene annotation and ontology. Correlation-based network analysis, where metabolites are arranged into network formation, is used as a complentary tool. Here, we demonstrate the detection of metabolic pathways based on correlation-based network analysis combined with machine-learning techniques. Metabolites of known tomato pathways, non-tomato pathways, and random sets of metabolites were mapped as subgraphs onto metabolite correlation networks of the tomato pericarp. Network features were computed for each subgraph, generating a machine-learning model. The model predicted the presence of the β-alanine-degradation-I, tryptophan-degradation-VII-via-indole-3-pyruvate (yet unknown to plants), the β-alanine-biosynthesis-III, and the melibiose-degradation pathway, although melibiose was not part of the networks. In vivo assays validated the presence of the melibiose-degradation pathway. For the remaining pathways only some of the genes encoding regulatory enzymes were detected.