Expression of cholera toxin B subunit in transgenic tomato plants.

PubMed

Jani, Dewal; Meena, Laxman Singh; Rizwan-ul-Haq, Quazi Mohammad; Singh, Yogendra; Sharma, Arun K; Tyagi, Akhilesh K

2002-10-01

Cholera toxin, secreted by Vibrio cholerae, consists of A and B subunits. The latter binds to G(M1)-ganglioside receptors as a pentamer (approximately 55 kDa). Tomato plants were transformed with the gene encoding cholera toxin B subunit (ctxB) along with an endoplasmic reticulum retention signal (SEKDEL) under the control of the CaMV 35S promoter via Agrobacterium-mediated transformation. PCR and Southern analysis confirmed the presence of the ctxB gene in transformed tomato plants. Northern analysis showed the presence of the ctxB-specific transcript. Immunoblot assays of the plant-derived protein extract showed the presence of cholera toxin subunit B (CTB) with mobility similar to purified CTB from V. cholerae. Both tomato leaves and fruits expressed CTB at levels up to 0.02 and 0.04% of total soluble protein, respectively. The G(M1)-ELISA showed that the plant-derived CTB bound specifically to G(M1)-ganglioside receptor, suggesting that it retained its native pentameric form. This study forms a basis for exploring the utility of CTB to develop tomato-based edible vaccines against cholera.

Parasitic Cuscuta factor(s) and the detection by tomato initiates plant defense.

PubMed

Fürst, Ursula; Hegenauer, Volker; Kaiser, Bettina; Körner, Max; Welz, Max; Albert, Markus

2016-01-01

Dodders ( Cuscuta spp.) are holoparasitic plants that enwind stems of host plants and penetrate those by haustoria to connect to the vascular bundles. Having a broad host plant spectrum, Cuscuta spp infect nearly all dicot plants - only cultivated tomato as one exception is mounting an active defense specifically against C. reflexa . In a recent work we identified a pattern recognition receptor of tomato, "Cuscuta Receptor 1" (CuRe1), which is critical to detect a "Cuscuta factor" (CuF) and initiate defense responses such as the production of ethylene or the generation of reactive oxygen species. CuRe1 also contributes to the tomato resistance against C. reflexa . Here we point to the fact that CuRe1 is not the only relevant component for full tomato resistance but it requires additional defense mechanisms, or receptors, respectively, to totally fend off the parasite.

Plant responses to tomato chlorotic mottle virus: Proteomic view of the resistance mechanisms to a bipartite begomovirus in tomato.

PubMed

Carmo, Lílian S T; Murad, André M; Resende, Renato O; Boiteux, Leonardo S; Ribeiro, Simone G; Jorrín-Novo, Jesús V; Mehta, Angela

2017-01-16

Tomato chlorotic mottle virus (ToCMoV) is a widespread bipartite Begomovirus species found in tomato fields in Brazil. In this study, plant responses and putative mechanisms associated with the 'Tyking'-derived recessive resistance to ToCMoV were investigated. Changes in the protein profile in the inoculated plants of two near isogenic tomato lines resistant ('LAM 157') and susceptible ('Santa Clara') to ToCMoV were analyzed. Seedlings were biolistically inoculated with an infectious ToCMoV clone. Leaves from infected plants (confirmed by PCR) were sampled at 15days after inoculation. Proteins were extracted using phenol and analyzed by shotgun MS (2D-nanoUPLC/HDMS E ). Out of the 534 identified proteins, 82 presented statistically significant differences in abundance, including 35 unique proteins displayed in the resistant tomato inoculated with ToCMoV. Proteins associated to chromatin structure, cytoskeleton structure, cuticle biosynthesis, and ubiquitin pathway were identified and their putative roles during virus infection process were discussed. The protein profile analysis allowed for the development of a hypothetical model showing how the resistant host cell responds to ToCMoV infection. The data obtained provide a better understanding of resistant mechanisms used by the host plant to contain viral infection and could be the basis for further investigation in other plant-begomovirus pathosystems. In this study we propose a model of resistance to begomovirus in tomato and highlight host proteins, which could be targets for future investigations in plant-begomovirus pathosystems. Copyright © 2016 Elsevier B.V. All rights reserved.

Parasitic Cuscuta factor(s) and the detection by tomato initiates plant defense

PubMed Central

Fürst, Ursula; Hegenauer, Volker; Kaiser, Bettina; Körner, Max; Welz, Max; Albert, Markus

2016-01-01

ABSTRACT Dodders (Cuscuta spp.) are holoparasitic plants that enwind stems of host plants and penetrate those by haustoria to connect to the vascular bundles. Having a broad host plant spectrum, Cuscuta spp infect nearly all dicot plants – only cultivated tomato as one exception is mounting an active defense specifically against C. reflexa. In a recent work we identified a pattern recognition receptor of tomato, “Cuscuta Receptor 1“ (CuRe1), which is critical to detect a “Cuscuta factor” (CuF) and initiate defense responses such as the production of ethylene or the generation of reactive oxygen species. CuRe1 also contributes to the tomato resistance against C. reflexa. Here we point to the fact that CuRe1 is not the only relevant component for full tomato resistance but it requires additional defense mechanisms, or receptors, respectively, to totally fend off the parasite. PMID:28042379

Highly sensitive serological methods for detecting tomato yellow leaf curl virus in tomato plants and whiteflies.

PubMed

Xie, Yan; Jiao, Xiaoyang; Zhou, Xueping; Liu, Huan; Ni, Yuequn; Wu, Jianxiang

2013-05-06

Tomato yellow leaf curl virus (TYLCV) is a member of the genus Begomovirus in the family Geminiviridae, which causes severe losses in tomato production in tropic and subtropic regions. The purified TYLCV virions were used as the immunogen to produce monoclonal antibodies (MAbs) using the hybridoma technology. MAb-based dot enzyme-linked immunosorbent assay (dot-ELISA) and direct tissue blot immunoassay (DTBIA) were developed for sensitive, simple, and rapid detection of TYLCV in field tomato and whitefly (Bemisia tabaci) samples collected from TYLCV prevalent provinces in China. Using the hybridoma technology, six murine MAbs (1C4, 8D10, 6E3, 2F2, 3F4 and 4G3) against TYLCV were prepared. Using the MAb 1C4, dot-ELISA and DTBIA were then established for detecting TYLCV in field tomato and whitefly samples collected from TYLCV prevalent provinces in China. The dot-ELISA could detect TYLCV in infected tissue crude extract diluted at 1:5,120 (w/v, g mL-1), and in viruliferous whitefly homogenate diluted at 1:128 (individual whitefly/μL), respectively. Field tomato samples (n=487) and whitefly samples (n=110) from TYLCV prevalent districts in China were screened for the presence of TYLCV using the two developed methods, and the results were further confirmed by PCR and nucleotide sequencing. The survey revealed that TYLCV is widespread on tomato plants in Zhejiang, Shandong and Henan provinces in China. The developed dot-ELISA is very suitable for the routine detection of TYLCV in field tomato and whitefly samples, and the DTBIA is more suitable for the routine detection of TYLCV in large-scale tomato plant samples collected from TYLCV prevalent areas.

Tomato chocolàte virus: a new plant virus infecting tomato and a proposed member of the genus Torradovirus.

PubMed

Verbeek, Martin; Dullemans, Annette; van den Heuvel, Hans; Maris, Paul; van der Vlugt, René

2010-05-01

A new virus was isolated from a tomato plant from Guatemala showing necrotic spots on the bases of the leaves and chocolate-brown patches on the fruits. Structural and molecular analysis showed the virus to be clearly related to but distinct from the recently described Tomato torrado virus (ToTV) and Tomato marchitez virus (ToMarV), both members of the genus Torradovirus. The name tomato chocolàte virus is proposed for this new torradovirus.

Resistance Inducers Modulate Pseudomonas syringae pv. Tomato Strain DC3000 Response in Tomato Plants

PubMed Central

Scalschi, Loredana; Camañes, Gemma; Llorens, Eugenio; Fernández-Crespo, Emma; López, María M.; García-Agustín, Pilar; Vicedo, Begonya

2014-01-01

The efficacy of hexanoic acid (Hx) as an inducer of resistance in tomato plants against Pseudomonas syringae pv. tomato DC3000 was previously demonstrated, and the plant response was characterized. Because little is known about the reaction of the pathogen to this effect, the goal of the present work was to determine whether the changes in the plant defence system affect the pathogen behaviour. This work provides the first demonstration of the response of the pathogen to the changes observed in plants after Hx application in terms of not only the population size but also the transcriptional levels of genes involved in quorum sensing establishment and pathogenesis. Therefore, it is possible that Hx treatment attenuates the virulence and survival of bacteria by preventing or diminishing the appearance of symptoms and controlling the growth of the bacteria in the mesophyll. It is interesting to note that the gene transcriptional changes in the bacteria from the treated plants occur at the same time as the changes in the plants. Hx is able to alter bacteria pathogenesis and survival only when it is applied as a resistance inducer because the changes that it promotes in plants affect the bacteria. PMID:25244125

Native soils with their microbiotas elicit a state of alert in tomato plants.

PubMed

Chialva, Matteo; Salvioli di Fossalunga, Alessandra; Daghino, Stefania; Ghignone, Stefano; Bagnaresi, Paolo; Chiapello, Marco; Novero, Mara; Spadaro, Davide; Perotto, Silvia; Bonfante, Paola

2018-02-09

Several studies have investigated soil microbial biodiversity, but understanding of the mechanisms underlying plant responses to soil microbiota remains in its infancy. Here, we focused on tomato (Solanum lycopersicum), testing the hypothesis that plants grown on native soils display different responses to soil microbiotas. Using transcriptomics, proteomics, and biochemistry, we describe the responses of two tomato genotypes (susceptible or resistant to Fusarium oxysporum f. sp. lycopersici) grown on an artificial growth substrate and two native soils (conducive and suppressive to Fusarium). Native soils affected tomato responses by modulating pathways involved in responses to oxidative stress, phenol biosynthesis, lignin deposition, and innate immunity, particularly in the suppressive soil. In tomato plants grown on steam-disinfected soils, total phenols and lignin decreased significantly. The inoculation of a mycorrhizal fungus partly rescued this response locally and systemically. Plants inoculated with the fungal pathogen showed reduced disease symptoms in the resistant genotype in both soils, but the susceptible genotype was partially protected from the pathogen only when grown on the suppressive soil. The 'state of alert' detected in tomatoes reveals novel mechanisms operating in plants in native soils and the soil microbiota appears to be one of the drivers of these plant responses. © 2018 The Authors. New Phytologist © 2018 New Phytologist Trust.

Technical feasibility and carbon footprint of biochar co-production with tomato plant residue.

PubMed

Llorach-Massana, Pere; Lopez-Capel, Elisa; Peña, Javier; Rieradevall, Joan; Montero, Juan Ignacio; Puy, Neus

2017-09-01

World tomato production is in the increase, generating large amounts of organic agricultural waste, which are currently incinerated or composted, releasing CO 2 into the atmosphere. Organic waste is not only produced from conventional but also urban agricultural practices due recently gained popularity. An alternative to current waste management practices and carbon sequestration opportunity is the production of biochar (thermally converted biomass) from tomato plant residues and use as a soil amendment. To address the real contribution of biochar for greenhouse gas mitigation, it is necessary to assess the whole life cycle from the production of the tomato biomass feedstock to the actual distribution and utilisation of the biochar produced in a regional context. This study is the first step to determine the technical and environmental potential of producing biochar from tomato plant (Solanum lycopersicum arawak variety) waste biomass and utilisation as a soil amendment. The study includes the characterisation of tomato plant residue as biochar feedstock (cellulose, hemicellulose, lignin and metal content); feedstock thermal stability; and the carbon footprint of biochar production under urban agriculture at pilot and small-scale plant, and conventional agriculture at large-scale plant. Tomato plant residue is a potentially suitable biochar feedstock under current European Certification based on its lignin content (19.7%) and low metal concentration. Biomass conversion yields of over 40%, 50% carbon stabilization and low pyrolysis temperature conditions (350-400°C) would be required for biochar production to sequester carbon under urban pilot scale conditions; while large-scale biochar production from conventional agricultural practices have not the potential to sequestrate carbon because its logistics, which could be improved. Therefore, the diversion of tomato biomass waste residue from incineration or composting to biochar production for use as a soil amendment

Tobacco overexpressing β-ocimene induces direct and indirect responses against aphids in receiver tomato plants.

PubMed

Cascone, Pasquale; Iodice, Luigi; Maffei, Massimo E; Bossi, Simone; Arimura, Gen-Ichiro; Guerrieri, Emilio

2015-01-15

In the last decade plant-to-plant communication has received an increasing attention, particularly for the role of Volatile Organic Compounds as possible elicitors of plant defense. The role of β-ocimene as an interspecific elicitor of plant defense has been recently assessed in multitrophic systems including different plant species (Solanaceae, Poaceae, legumes) and different pest species including chewer insects and phytophagous mites. Both chewer insects and phytophagous mites are known to elicit specific plant defensive pathways which are different (at least in part) from those elicited by sap feeders. The aim of this research was to fill this gap of knowledge and to assess the role of β-ocimene as an elicitor of plant defense against aphid pests, which are sap feeders. For this purpose we used as transgenic tobacco plant releasing an odour plume enriched in this compound as emitter and a tomato plant as receiver. We selected the aphid Macrosiphum euphorbiae and its natural enemy, the parasitoid Aphidius ervi, as the targets of plant induced defense. Tomato plant defense induced by β-ocimene was assessed by characterizing the aphid performance in terms of fixing behaviour, development and reproduction (direct plant defense) and the parasitoid performance in terms of attraction towards tomato plants (indirect plant defense). The characterization of tomato response to β-ocimene was completed by the identification of Volatile Organic Compounds as released by conditioned tomato plants. Tomato plants that were exposed to the volatiles of transgenic tobacco enriched in β-ocimene resulted in less suitable for the aphids in respect to control ones (direct defense). On tomato plants "elicited" by β-ocimene we recorded: a significant lower number of aphids settled; a significant lower number newborn nymphs; a significant lower weight of aphids feeding. In addition, tomato plants "elicited" by β-ocimene resulted became more attractive towards the parasitoid A. ervi

Dispersal of Salmonella Typhimurium by rain splash onto tomato plants.

PubMed

Cevallos-Cevallos, Juan M; Danyluk, Michelle D; Gu, Ganyu; Vallad, Gary E; van Bruggen, Ariena H C

2012-03-01

Outbreaks of Salmonella enterica have increasingly been associated with tomatoes and traced back to production areas, but the spread of Salmonella from a point source onto plants has not been described. Splash dispersal by rain could be one means of dissemination. Green fluorescent protein-labeled, kanamycin-resistant Salmonella enterica sv. Typhimurium dispensed on the surface of plastic mulch, organic mulch, or soil at 10⁸ CFU/cm² was used as the point source in the center of a rain simulator. Tomato plants in soil with and without plastic or organic mulch were placed around the point source, and rain intensities of 60 and 110 mm/h were applied for 5, 10, 20, and 30 min. Dispersal of Salmonella followed a negative exponential model with a half distance of 3 cm at 110 mm/h. Dispersed Salmonella survived for 3 days on tomato leaflets, with a total decline of 5 log and an initial decimal reduction time of 10 h. Recovery of dispersed Salmonella from plants at the maximum observed distance ranged from 3 CFU/g of leaflet after a rain episode of 110 mm/h for 10 min on soil to 117 CFU/g of leaflet on plastic mulch. Dispersal of Salmonella on plants with and without mulch was significantly enhanced by increasing rain duration from 0 to 10 min, but dispersal was reduced when rainfall duration increased from 10 to 30 min. Salmonella may be dispersed by rain to contaminate tomato plants in the field, especially during rain events of 10 min and when plastic mulch is used.

Graft Angle its Relationship to Tomato Plant Survival

USDA-ARS?s Scientific Manuscript database

Growing plants that can withstand the rigors of open field production is imperative. This study examines the relationship of tensile strength to graft angle and plant survival. Tomato seedlings of ‘FL47’ and ‘Rutgers’ were used as scions on ‘Roma’ rootstock under greenhouse and healing chamber con...

LEFPS1, a Tomato Farnesyl Pyrophosphate Gene Highly Expressed during Early Fruit Development1

PubMed Central

Gaffe, Joel; Bru, Jean-Philippe; Causse, Mathilde; Vidal, Alain; Stamitti-Bert, Linda; Carde, Jean-Pierre; Gallusci, Philippe

2000-01-01

Farnesyl pyrophosphate synthase (FPS) catalyzes the synthesis of farnesyl pyrophosphate, a key intermediate in sterol and sesquiterpene biosynthesis. Using a polymerase chain reaction-based approach, we have characterized LeFPS1, a tomato (Lycoperscion esculentum cv Wva 106) fruit cDNA, which encodes a functional FPS. We demonstrate that tomato FPSs are encoded by a small multigenic family with genes located on chromosomes 10 and 12. Consistent with farnesyl pyrophosphate requirement in sterol biosynthesis, FPS genes are ubiquitously expressed in tomato plants. Using an LeFPS1 specific probe, we show that the corresponding gene can account for most of FPS mRNA in most plant organs, but not during young seedling development, indicating a differential regulation of FPS genes in tomato. FPS gene expression is also under strict developmental control: FPS mRNA was mainly abundant in young organs and decreased as organs matured with the exception of fruits that presented a biphasic accumulation pattern. In this latter case in situ hybridization studies have shown that FPS mRNA is similarly abundant in all tissues of young fruit. Taken together our results suggest that several FPS isoforms are involved in tomato farnesyl pyrophosphate metabolism and that FPS genes are mostly expressed in relation to cell division and enlargement. PMID:10938353

Infection of Helicoverpa armigera by endophytic Beauveria bassiana colonizing tomato plants

USDA-ARS?s Scientific Manuscript database

A novel endophytic strain of Beauveria bassiana was isolated from leaf tissue of a wild tomato plant. This strain and two B. bassiana strains previously isolated from soil were evaluated for their ability to endophytically colonize tomatoes and subsequent in planta efficacy against Helicoverpa armig...

Plant the Seeds of Safety

ERIC Educational Resources Information Center

Roy, Ken

2004-01-01

Both indoor and outdoor garden plants can cause problems. For example, the foliage of the bird-of-paradise and philodendron plants is toxic. A poinsettia leaf can kill a young child. Outdoor plants such as castor beans are highly dangerous. All parts of the potato and tomato plant are poisonous, except the potato and tomato themselves. Large…

Involvement of plant endogenous ABA in Bacillus megaterium PGPR activity in tomato plants.

PubMed

Porcel, Rosa; Zamarreño, Ángel María; García-Mina, José María; Aroca, Ricardo

2014-01-25

Plant growth-promoting rhizobacteria (PGPR) are naturally occurring soil bacteria which benefit plants by improving plant productivity and immunity. The mechanisms involved in these processes include the regulation of plant hormone levels such as ethylene and abscisic acid (ABA). The aim of the present study was to determine whether the activity of Bacillus megaterium PGPR is affected by the endogenous ABA content of the host plant. The ABA-deficient tomato mutants flacca and sitiens and their near-isogenic wild-type parental lines were used. Growth, stomatal conductance, shoot hormone concentration, competition assay for colonization of tomato root tips, and root expression of plant genes expected to be modulated by ABA and PGPR were examined. Contrary to the wild-type plants in which PGPR stimulated growth rates, PGPR caused growth inhibition in ABA-deficient mutant plants. PGPR also triggered an over accumulation of ethylene in ABA-deficient plants which correlated with a higher expression of the pathogenesis-related gene Sl-PR1b. Positive correlation between over-accumulation of ethylene and a higher expression of Sl-PR1b in ABA-deficient mutant plants could indicate that maintenance of normal plant endogenous ABA content may be essential for the growth promoting action of B. megaterium by keeping low levels of ethylene production.

Baseline survey of the anatomical microbial ecology of an important food plant: Solanum lycopersicum (tomato)

PubMed Central

2013-01-01

Background Research to understand and control microbiological risks associated with the consumption of fresh fruits and vegetables has examined many environments in the farm to fork continuum. An important data gap however, that remains poorly studied is the baseline description of microflora that may be associated with plant anatomy either endemically or in response to environmental pressures. Specific anatomical niches of plants may contribute to persistence of human pathogens in agricultural environments in ways we have yet to describe. Tomatoes have been implicated in outbreaks of Salmonella at least 17 times during the years spanning 1990 to 2010. Our research seeks to provide a baseline description of the tomato microbiome and possibly identify whether or not there is something distinctive about tomatoes or their growing ecology that contributes to persistence of Salmonella in this important food crop. Results DNA was recovered from washes of epiphytic surfaces of tomato anatomical organs; leaves, stems, roots, flowers and fruits of Solanum lycopersicum (BHN602), grown at a site in close proximity to commercial farms previously implicated in tomato-Salmonella outbreaks. DNA was amplified for targeted 16S and 18S rRNA genes and sheared for shotgun metagenomic sequencing. Amplicons and metagenomes were used to describe “native” bacterial microflora for diverse anatomical parts of Virginia-grown tomatoes. Conclusions Distinct groupings of microbial communities were associated with different tomato plant organs and a gradient of compositional similarity could be correlated to the distance of a given plant part from the soil. Unique bacterial phylotypes (at 95% identity) were associated with fruits and flowers of tomato plants. These include Microvirga, Pseudomonas, Sphingomonas, Brachybacterium, Rhizobiales, Paracocccus, Chryseomonas and Microbacterium. The most frequently observed bacterial taxa across aerial plant regions were Pseudomonas and Xanthomonas

Qualitative and Quantitative Differences in Herbivore-Induced Plant Volatile Blends from Tomato Plants Infested by Either Tuta absoluta or Bemisia tabaci.

PubMed

Silva, Diego B; Weldegergis, Berhane T; Van Loon, Joop J A; Bueno, Vanda H P

2017-01-01

Plants release a variety of volatile organic compounds that play multiple roles in the interactions with other plants and animals. Natural enemies of plant-feeding insects use these volatiles as cues to find their prey or host. Here, we report differences between the volatile blends of tomato plants infested with the whitefly Bemisia tabaci or the tomato borer Tuta absoluta. We compared the volatile emission of: (1) clean tomato plants; (2) tomato plants infested with T. absoluta larvae; and (3) tomato plants infested with B. tabaci adults, nymphs, and eggs. A total of 80 volatiles were recorded of which 10 occurred consistently only in the headspace of T. absoluta-infested plants. Many of the compounds detected in the headspace of the two herbivory treatments were emitted at different rates. Plants damaged by T. absoluta emitted at least 10 times higher levels of many compounds compared to plants damaged by B. tabaci and intact plants. The multivariate separation of T. absoluta-infested plants from those infested with B. tabaci was due largely to the chorismate-derived compounds as well as volatile metabolites of C 18 -fatty acids and branched chain amino acids that had higher emission rates from T. absoluta-infested plants, whereas the cyclic sesquiterpenes α- and β-copaene, valencene, and aristolochene were emitted at significantly higher levels from B. tabaci-infested plants. Our findings imply that feeding by T. absoluta and B. tabaci induced emission of volatile blends that differ quantitatively and qualitatively, providing a chemical basis for the recently documented behavioral discrimination by two generalist predatory mirid species, natural enemies of T. absoluta and B. tabaci employed in biological control.

Transcriptome Analysis of Plant Hormone-Related Tomato (Solanum lycopersicum) Genes in a Sunlight-Type Plant Factory.

PubMed

Tanigaki, Yusuke; Higashi, Takanobu; Takayama, Kotaro; Nagano, Atsushi J; Honjo, Mie N; Fukuda, Hirokazu

2015-01-01

In plant factories, measurements of plant conditions are necessary at an early stage of growth to predict harvest times of high value-added crops. Moreover, harvest qualities depend largely on environmental stresses that elicit plant hormone responses. However, the complexities of plant hormone networks have not been characterized under nonstress conditions. In the present study, we determined temporal expression profiles of all genes and then focused on plant hormone pathways using RNA-Seq analyses of gene expression in tomato leaves every 2 h for 48 h. In these experiments, temporally expressed genes were found in the hormone synthesis pathways for salicylic acid, abscisic acid, ethylene, and jasmonic acid. The timing of CAB expression 1 (TOC1) and abscisic acid insensitive 1 (ABA1) and open stomata 1 (OST1) control gating stomata. In this study, compare with tomato and Arabidopsis thaliana, expression patterns of TOC1 have similarity. In contrast, expression patterns of tomato ABI1 and OST1 had expression peak at different time. These findings suggest that the regulation of gating stomata does not depend predominantly on TOC1 and significantly reflects the extracellular environment. The present data provide new insights into relationships between temporally expressed plant hormone-related genes and clock genes under normal sunlight conditions.

Transcriptome Analysis of Plant Hormone-Related Tomato (Solanum lycopersicum) Genes in a Sunlight-Type Plant Factory

PubMed Central

Tanigaki, Yusuke; Higashi, Takanobu; Takayama, Kotaro; Nagano, Atsushi J.; Honjo, Mie N.; Fukuda, Hirokazu

2015-01-01

In plant factories, measurements of plant conditions are necessary at an early stage of growth to predict harvest times of high value-added crops. Moreover, harvest qualities depend largely on environmental stresses that elicit plant hormone responses. However, the complexities of plant hormone networks have not been characterized under nonstress conditions. In the present study, we determined temporal expression profiles of all genes and then focused on plant hormone pathways using RNA-Seq analyses of gene expression in tomato leaves every 2 h for 48 h. In these experiments, temporally expressed genes were found in the hormone synthesis pathways for salicylic acid, abscisic acid, ethylene, and jasmonic acid. The timing of CAB expression 1 (TOC1) and abscisic acid insensitive 1 (ABA1) and open stomata 1 (OST1) control gating stomata. In this study, compare with tomato and Arabidopsis thaliana, expression patterns of TOC1 have similarity. In contrast, expression patterns of tomato ABI1 and OST1 had expression peak at different time. These findings suggest that the regulation of gating stomata does not depend predominantly on TOC1 and significantly reflects the extracellular environment. The present data provide new insights into relationships between temporally expressed plant hormone-related genes and clock genes under normal sunlight conditions. PMID:26624004

Graft union formation in tomato plants: peroxidase and catalase involvement.

PubMed

Fernandez-Garcia, Nieves; Carvajal, Micaela; Olmos, Enrique

2004-01-01

The use of grafted plants in vegetable crop production is now being expanded greatly. However, few data are available on the formation of graft unions in vegetables. In this work, the structural development of the graft union formation in tomato plants is studied, together with the possible relationship with activities of peroxidases and catalases. Tomato (Lycopersicon esculentum Mill.) seedlings of cultivar Fanny were grafted on the rootstock of cultivar AR-9704 using the 'tongue approach grafting' method, and were grown in a crop chamber. A study of the structural development of the graft union and the involvement of peroxidases and catalases in the process of graft formation was carried out during the first stages of the graft union (4, 8 and 15 d after grafting). Observation of the structure of the graft union showed formation of xylem and phloem vessels through the graft union 8 d after grafting. In addition, root hydraulic conductance, L0, indicate that the graft union is fully functional 8 d after grafting, which coincided with an increase of peroxidase and catalase activities. These results suggest that increased peroxidase and catalase activities might be implicated in graft development in tomato plants.

Plant-to-plant communication triggered by systemin primes anti-herbivore resistance in tomato.

PubMed

Coppola, Mariangela; Cascone, Pasquale; Madonna, Valentina; Di Lelio, Ilaria; Esposito, Francesco; Avitabile, Concetta; Romanelli, Alessandra; Guerrieri, Emilio; Vitiello, Alessia; Pennacchio, Francesco; Rao, Rosa; Corrado, Giandomenico

2017-11-14

Plants actively respond to herbivory by inducing various defense mechanisms in both damaged (locally) and non-damaged tissues (systemically). In addition, it is currently widely accepted that plant-to-plant communication allows specific neighbors to be warned of likely incoming stress (defense priming). Systemin is a plant peptide hormone promoting the systemic response to herbivory in tomato. This 18-aa peptide is also able to induce the release of bioactive Volatile Organic Compounds, thus also promoting the interaction between the tomato and the third trophic level (e.g. predators and parasitoids of insect pests). In this work, using a combination of gene expression (RNA-Seq and qRT-PCR), behavioral and chemical approaches, we demonstrate that systemin triggers metabolic changes of the plant that are capable of inducing a primed state in neighboring unchallenged plants. At the molecular level, the primed state is mainly associated with an elevated transcription of pattern -recognition receptors, signaling enzymes and transcription factors. Compared to naïve plants, systemin-primed plants were significantly more resistant to herbivorous pests, more attractive to parasitoids and showed an increased response to wounding. Small peptides are nowadays considered fundamental signaling molecules in many plant processes and this work extends the range of downstream effects of this class of molecules to intraspecific plant-to-plant communication.

Tomato ethylene sensitivity determines interaction with plant growth-promoting bacteria.

PubMed

Ibort, Pablo; Molina, Sonia; Núñez, Rafael; Zamarreño, Ángel María; García-Mina, José María; Ruiz-Lozano, Juan Manuel; Orozco-Mosqueda, Maria Del Carmen; Glick, Bernard R; Aroca, Ricardo

2017-07-01

Plant growth-promoting bacteria (PGPB) are soil micro-organisms able to interact with plants and stimulate their growth, positively affecting plant physiology and development. Although ethylene plays a key role in plant growth, little is known about the involvement of ethylene sensitivity in bacterial inoculation effects on plant physiology. Thus, the present study was pursued to establish whether ethylene perception is critical for plant-bacteria interaction and growth induction by two different PGPB strains, and to assess the physiological effects of these strains in juvenile and mature tomato ( Solanum lycopersicum ) plants. An experiment was performed with the ethylene-insensitive tomato never ripe and its isogenic wild-type line in which these two strains were inoculated with either Bacillus megaterium or Enterobacter sp. C7. Plants were grown until juvenile and mature stages, when biomass, stomatal conductance, photosynthesis as well as nutritional, hormonal and metabolic statuses were analysed. Bacillus megaterium promoted growth only in mature wild type plants. However, Enterobacter C7 PGPB activity affected both wild-type and never ripe plants. Furthermore, PGPB inoculation affected physiological parameters and root metabolite levels in juvenile plants; meanwhile plant nutrition was highly dependent on ethylene sensitivity and was altered at the mature stage. Bacillus megaterium inoculation improved carbon assimilation in wild-type plants. However, insensitivity to ethylene compromised B. megaterium PGPB activity, affecting photosynthetic efficiency, plant nutrition and the root sugar content. Nevertheless, Enterobacter C7 inoculation modified the root amino acid content in addition to stomatal conductance and plant nutrition. Insensitivity to ethylene severely impaired B. megaterium interaction with tomato plants, resulting in physiological modifications and loss of PGPB activity. In contrast, Enterobacter C7 inoculation stimulated growth independently of

Influence of simulated Quinclorac drift on the accumulation and movement of herbicide in tomato (Lycopersicon esculentum) plants.

PubMed

Lovelace, Michael L; Hoagland, Robert E; Talbert, Ronald E; Scherder, Eric F

2009-07-22

Quinclorac (3,7-dichloro-8-quinolinecarboxylic acid) is a herbicide commonly used in rice, and its drift has been suspected of causing injury to off-target tomato fields throughout Arkansas. Studies were conducted to evaluate the effects of single and multiple simulated quinclorac drift applications on tomato plant growth and development. Residues extracted from tomato plants treated with 0.42 g of ai ha(-1) were below the detection limit of liquid chromatography-double mass spectrometry (LC-MS/MS) analysis. Quinclorac residue levels and half-lives in tomato tissue increased as the application rate and number of applications increased. From 3 to 72 h after (14)C-quinclorac treatment of plants, most of the absorbed (14)C was retained in the treated leaf, and translocations of (14)C out of the treated leaf of vegetative and flowering tomato plant tissues were similar. Of the (14)C that translocated out of the treated leaf, the greatest movement was acropetally. The flower cluster contained 1% of the total absorbed (14)C, which suggests the potential for quinclorac translocation into tomato fruit. More extensive research will be required to understand the impact that quinclorac may have on tomato production in the area.

Elevated O3 enhances the attraction of whitefly-infested tomato plants to Encarsia formosa

PubMed Central

Cui, Hongying; Su, Jianwei; Wei, Jianing; Hu, Yongjian; Ge, Feng

2014-01-01

We experimentally examined the effects of elevated O3 and whitefly herbivory on tomato volatiles, feeding and oviposition preferences of whiteflies and behavioural responses of Encarsia formosa to these emissions on two tomato genotypes, a wild-type (Wt) and a jasmonic acid (JA) defence-enhanced genotype (JA-OE, 35S). The O3 level and whitefly herbivory significantly increased the total amount of volatile organic compounds (VOCs), monoterpenes, green leaf volatiles (GLVs), and aldehyde volatiles produced by tomato plants. The 35S plants released higher amount of total VOCs and monoterpene volatiles than Wt plants under O3+herbivory treatments. The feeding and oviposition bioassays showed that control plants were preferred by adult whiteflies whereas the 35S plants were not preferred by whiteflies. In the Y-tube tests, O3+herbivory treatment genotypes were preferred by adult E. Formosa. The 35S plants were preferred by adult E. formosa under O3, herbivory and O3+herbivory treatments. Our results demonstrated that elevated O3 and whitefly herbivory significantly increased tomato volatiles, which attracted E. formosa and reduced whitefly feeding. The 35S plants had a higher resistance to B. tabaci than Wt plant. Such changes suggest that the direct and indirect defences of resistant genotypes, such as 35S, could strengthen as the atmospheric O3 concentration increases. PMID:24939561

A Calcium-Dependent Protein Kinase Is Systemically Induced upon Wounding in Tomato Plants1

PubMed Central

Chico, José Manuel; Raíces, Marcela; Téllez-Iñón, María Teresa; Ulloa, Rita María

2002-01-01

A full-length cDNA clone (LeCDPK1) from tomato (Lycopersicon esculentum) encoding a calcium-dependent protein kinase (CDPK) was isolated by screening a cDNA library from tomato cell cultures exposed to Cladosporium fulvum elicitor preparations. The predicted amino acid sequence of the cDNA reveals a high degree of similarity with other members of the CDPK family. LeCDPK1 has a putative N-terminal myristoylation sequence and presents a possible palmitoylation site. The in vitro translated protein conserves the biochemical properties of a member of the CDPK family. In addition, CDPK activity was detected in soluble and particulate extracts of tomato leaves. Basal levels of LeCDPK1 mRNA were detected by northern-blot analysis in roots, stems, leaves, and flowers of tomato plants. The expression of LeCDPK1 was rapidly and transiently enhanced in detached tomato leaves treated with pathogen elicitors and H2O2. Moreover, when tomato greenhouse plants were subjected to mechanical wounding, a transient increase of LeCDPK1 steady-state mRNA levels was detected locally at the site of the injury and systemically in distant non-wounded leaves. The increase observed in LeCDPK1 mRNA upon wounding correlates with an increase in the amount and in the activity of a soluble CDPK detected in extracts of tomato leaves, suggesting that this kinase is part of physiological plant defense mechanisms against biotic or abiotic attacks. PMID:11788771

Tomato juice supplementation in young women reduces inflammatory adipokine levels independently of body fat reduction.

PubMed

Li, Yu-Fen; Chang, Ya-Yuan; Huang, Hui-Chi; Wu, Yi-Chen; Yang, Mei-Due; Chao, Pei-Min

2015-05-01

Lycopene is a carotene and phytochemical known to protect against metabolic diseases. It is found in red fruits and vegetables, predominantly tomatoes. This study aimed to show the supplementation effect of tomato juice on indices associated with metabolic health and adipokine profiles in generally healthy people. A total of 30 young females (20- to 30-years-old) with a body mass index (BMI) ≥ 20 were recruited, of whom 25 completed the entire study. The subjects continued with their normal diet and exercise schedule, but were given 280 mL of tomato juice (containing 32.5 mg of lycopene) daily for 2 mo. Metabolic indices, including anthropometric data and serum levels of glucose, lipids, adipokines, lycopene, and antioxidants, were compared pre- and postintervention. Tomato juice supplementation significantly reduced body weight, body fat, waist circumference, BMI, and serum levels of cholesterol, monocyte chemoattractant protein-1 (MCP-1), and thiobarbituric reactive substances, while significantly increasing serum levels of adiponectin, triglyceride, and lycopene. When subjects were stratified by body fat change, i.e., reduction or non-reduction (including increase or no change), the tomato juice-induced reduction in waist circumference, serum cholesterol, and MCP-1 levels and increase in adiponectin and lycopene levels were seen in both subgroups. The changes in waist circumference, cholesterol, MCP-1, and adiponectin levels remained significant after adjusting for each covariable individually, with the exception of lycopene. These results show that daily tomato juice supplementation reduces waist circumference, as well as serum cholesterol and inflammatory adipokine levels in young healthy women and that these effects are unrelated to body fat changes. Copyright © 2015 Elsevier Inc. All rights reserved.

Interplant communication of tomato plants through underground common mycorrhizal networks.

PubMed

Song, Yuan Yuan; Zeng, Ren Sen; Xu, Jian Feng; Li, Jun; Shen, Xiang; Yihdego, Woldemariam Gebrehiwot

2010-10-13

Plants can defend themselves to pathogen and herbivore attack by responding to chemical signals that are emitted by attacked plants. It is well established that such signals can be transferred through the air. In theory, plants can also communicate with each other through underground common mycorrhizal networks (CMNs) that interconnect roots of multiple plants. However, until now research focused on plant-to-plant carbon nutrient movement and there is no evidence that defense signals can be exchanged through such mycorrhizal hyphal networks. Here, we show that CMNs mediate plant-plant communication between healthy plants and pathogen-infected tomato plants (Lycopersicon esculentum Mill.). After establishment of CMNs with the arbuscular mycorrhizal fungus Glomus mosseae between tomato plants, inoculation of 'donor' plants with the pathogen Alternaria solani led to increases in disease resistance and activities of the putative defensive enzymes, peroxidase, polyphenol oxidase, chitinase, β-1,3-glucanase, phenylalanine ammonia-lyase and lipoxygenase in healthy neighbouring 'receiver' plants. The uninfected 'receiver' plants also activated six defence-related genes when CMNs connected 'donor' plants challenged with A. solani. This finding indicates that CMNs may function as a plant-plant underground communication conduit whereby disease resistance and induced defence signals can be transferred between the healthy and pathogen-infected neighbouring plants, suggesting that plants can 'eavesdrop' on defence signals from the pathogen-challenged neighbours through CMNs to activate defences before being attacked themselves.

Bioluminescence imaging of Clavibacter michiganensis subsp. michiganensis infection of tomato seeds and plants.

PubMed

Xu, Xiulan; Miller, Sally A; Baysal-Gurel, Fulya; Gartemann, Karl-Heinz; Eichenlaub, Rudolf; Rajashekara, Gireesh

2010-06-01

Clavibacter michiganensis subsp. michiganensis is a Gram-positive bacterium that causes wilting and cankers, leading to severe economic losses in commercial tomato production worldwide. The disease is transmitted from infected seeds to seedlings and mechanically from plant to plant during seedling production, grafting, pruning, and harvesting. Because of the lack of tools for genetic manipulation, very little is known regarding the mechanisms of seed and seedling infection and movement of C. michiganensis subsp. michiganensis in grafted plants, two focal points for application of bacterial canker control measures in tomato. To facilitate studies on the C. michiganensis subsp. michiganensis movement in tomato seed and grafted plants, we isolated a bioluminescent C. michiganensis subsp. michiganensis strain using the modified Tn1409 containing a promoterless lux reporter. A total of 19 bioluminescent C. michiganensis subsp. michiganensis mutants were obtained. All mutants tested induced a hypersensitive response in Mirabilis jalapa and caused wilting of tomato plants. Real-time colonization studies of germinating seeds using a virulent, stable, constitutively bioluminescent strain, BL-Cmm17, showed that C. michiganensis subsp. michiganensis aggregated on hypocotyls and cotyledons at an early stage of germination. In grafted seedlings in which either the rootstock or scion was exposed to BL-Cmm17 via a contaminated grafting knife, bacteria were translocated in both directions from the graft union at higher inoculum doses. These results emphasize the use of bioluminescent C. michiganensis subsp. michiganensis to help better elucidate the C. michiganensis subsp. michiganensis-tomato plant interactions. Further, we demonstrated the broader applicability of this tool by successful transformation of C. michiganensis subsp. nebraskensis with Tn1409::lux. Thus, our approach would be highly useful to understand the pathogenesis of diseases caused by other subspecies of the

A Plant Phytosulfokine Peptide Initiates Auxin-Dependent Immunity through Cytosolic Ca2+ Signaling in Tomato[OPEN

PubMed Central

Zhang, Huan; Hu, Zhangjian; Lei, Cui; Zheng, Chenfei; Wang, Jiao; Shao, Shujun; Li, Xin; Xia, Xiaojian; Cai, Xinzhong

2018-01-01

Phytosulfokine (PSK) is a disulfated pentapeptide that is an important signaling molecule. Although it has recently been implicated in plant defenses to pathogen infection, the mechanisms involved remain poorly understood. Using surface plasmon resonance and gene silencing approaches, we showed that the tomato (Solanum lycopersicum) PSK receptor PSKR1, rather than PSKR2, functioned as the major PSK receptor in immune responses. Silencing of PSK signaling genes rendered tomato more susceptible to infection by the economically important necrotrophic pathogen Botrytis cinerea. Analysis of tomato mutants defective in either defense hormone biosynthesis or signaling demonstrated that PSK-induced immunity required auxin biosynthesis and associated defense pathways. Here, using aequorin-expressing tomato plants, we provide evidence that PSK perception by tomato PSKR1 elevated cytosolic [Ca2+], leading to auxin-dependent immune responses via enhanced binding activity between calmodulins and the auxin biosynthetic YUCs. Thus, our data demonstrate that PSK acts as a damage-associated molecular pattern and is perceived mainly by PSKR1, which increases cytosolic [Ca2+] and activates auxin-mediated pathways that enhance immunity of tomato plants to B. cinerea. PMID:29511053

Tomato plant and leaf age effects on the probing and settling behavior of Frankliniella fusca and Frankliniella occidentalis (Thysanoptera: Thripidae).

PubMed

Joost, P Houston; Riley, David G

2008-02-01

The effect of tomato, Solanum lycopersicum L., plant and leaf age on the probing and settling behavior of Frankliniella fusca (Hinds) and F. occidentalis (Pergande) was studied using electrical penetration graph technique and whole plant bioassays. Male and female F. fusca probed and ingested more and for longer periods of time on 3- and 4-wk-old plants compared with 6- and 8-wk-old plants. Female F. fusca probed and ingested more frequently than males in the plant age experiment, but not in the leaf age experiment. F. fusca probed and ingested more frequently on 2- and 4-wk-old leaves compared with 1-wk-old leaves. Plant age did not affect the probing frequency or duration of F. occidentalis; however, males probed and ingested longer than females in the plant age experiment and on the oldest leaf in the leaf age experiment. Both thrips species preferred to settle on 3-wk-old plants. F. fusca preferred to settle on 4-wk-old leaves after settling randomly for an hour. F. occidentalis showed no settling preference relative to leaf age. The preference of F. fusca for young plants suggests that this species could attack tomato plants at a very early stage, which is important for understanding its role as a vector in the transmission of Tospovirus in the field.

Plant insects and mites uptake double-stranded RNA upon its exogenous application on tomato leaves.

PubMed

Gogoi, Anupam; Sarmah, Nomi; Kaldis, Athanasios; Perdikis, Dionysios; Voloudakis, Andreas

2017-12-01

Exogenously applied double-stranded RNA (dsRNA) molecules onto tomato leaves, moved rapidly from local to systemic leaves and were uptaken by agricultural pests namely aphids, whiteflies and mites. Four small interfering RNAs, deriving from the applied dsRNA, were molecularly detected in plants, aphids and mites but not in whiteflies. Double-stranded RNA (dsRNA) acts as the elicitor molecule of the RNA silencing (RNA interference, RNAi), the endogenous and evolutionary conserved surveillance system present in all eukaryotes. DsRNAs and their subsequent degradation products, namely the small interfering RNAs (siRNAs), act in a sequence-specific manner to control gene expression. Exogenous application of dsRNAs onto plants elicits resistance against plant viruses. In the present work, exogenously applied dsRNA molecules, derived from Zucchini yellow mosaic virus (ZYMV) HC-Pro region, onto tomato plants were detected in aphids (Myzus persicae), whiteflies (Trialeurodes vaporariorum) and mites (Tetranychus urticae) that were fed on treated as well as systemic tomato leaves. Furthermore, four siRNAs, deriving from the dsRNA applied, were detected in tomato and the agricultural pests fed on treated tomato plants. More specifically, dsRNA was detected in agricultural pests at 3 and 10 dpt (days post treatment) in dsRNA-treated leaves and at 14 dpt in systemic leaves. In addition, using stem-loop RT-PCR, siRNAs were detected in agricultural pests at 3 and 10 dpt in aphids and mites. Surprisingly, in whiteflies carrying the applied dsRNA, siRNAs were not molecularly detected. Our results showed that, upon exogenous application of dsRNAs molecules, these moved rapidly within tomato and were uptaken by agricultural pests fed on treated tomato. As a result, this non-transgenic method has the potential to control important crop pests via RNA silencing of vital genes of the respective pests.

Highly Diverse Endophytic and Soil Fusarium oxysporum Populations Associated with Field-Grown Tomato Plants

PubMed Central

Demers, Jill E.; Gugino, Beth K.

2014-01-01

The diversity and genetic differentiation of populations of Fusarium oxysporum associated with tomato fields, both endophytes obtained from tomato plants and isolates obtained from soil surrounding the sampled plants, were investigated. A total of 609 isolates of F. oxysporum were obtained, 295 isolates from a total of 32 asymptomatic tomato plants in two fields and 314 isolates from eight soil cores sampled from the area surrounding the plants. Included in this total were 112 isolates from the stems of all 32 plants, a niche that has not been previously included in F. oxysporum population genetics studies. Isolates were characterized using the DNA sequence of the translation elongation factor 1α gene. A diverse population of 26 sequence types was found, although two sequence types represented nearly two-thirds of the isolates studied. The sequence types were placed in different phylogenetic clades within F. oxysporum, and endophytic isolates were not monophyletic. Multiple sequence types were found in all plants, with an average of 4.2 per plant. The population compositions differed between the two fields but not between soil samples within each field. A certain degree of differentiation was observed between populations associated with different tomato cultivars, suggesting that the host genotype may affect the composition of plant-associated F. oxysporum populations. No clear patterns of genetic differentiation were observed between endophyte populations and soil populations, suggesting a lack of specialization of endophytic isolates. PMID:25304514

Pre-meal tomato (Lycopersicon esculentum) intake can have anti-obesity effects in young women?

PubMed

Vinha, Ana F; Barreira, Sérgio V P; Costa, Anabela S G; Alves, Rita C; Oliveira, M Beatriz P P

2014-12-01

The effect of pre-meal tomato intake in the anthropometric indices and blood levels of triglycerides, cholesterol, glucose, and uric acid of a young women population (n = 35, 19.6 ± 1.3 years) was evaluated. During 4 weeks, daily, participants ingested a raw ripe tomato (∼90 g) before lunch. Their anthropometric and biochemical parameters were measured repeatedly during the follow-up time. At the end of the 4 weeks, significant reductions were observed on body weight (-1.09 ± 0.12 kg on average), % fat (-1.54 ± 0.52%), fasting blood glucose (-5.29 ± 0.80 mg/dl), triglycerides (-8.31 ± 1.34 mg/dl), cholesterol (-10.17 ± 1.21 mg/dl), and uric acid (-0.16 ± 0.04 mg/dl) of the participants. The tomato pre-meal ingestion seemed to interfere positively in body weight, fat percentage, and blood levels of glucose, triglycerides, cholesterol, and uric acid of the young adult women that participated in this study.

Preferential expression and immunogenicity of HIV-1 Tat fusion protein expressed in tomato plant.

PubMed

Cueno, Marni E; Hibi, Yurina; Karamatsu, Katsuo; Yasutomi, Yasuhiro; Imai, Kenichi; Laurena, Antonio C; Okamoto, Takashi

2010-10-01

HIV-1 Tat plays a major role in viral replication and is essential for AIDS development making it an ideal vaccine target providing that both humoral and cellular immune responses are induced. Plant-based antigen production, due to its cheaper cost, appears ideal for vaccine production. In this study, we created a plant-optimized tat and mutant (Cys30Ala/Lys41Ala) tat (mtat) gene and ligated each into a pBI121 expression vector with a stop codon and a gusA gene positioned immediately downstream. The vector construct was bombarded into tomato leaf calli and allowed to develop. We thus generated recombinant tomato plants preferentially expressing a Tat-GUS fusion protein over a Tat-only protein. In addition, plants bombarded with either tat or mtat genes showed no phenotypic difference and produced 2-4 microg Tat-GUS fusion protein per milligram soluble plant protein. Furthermore, tomato extracts intradermally inoculated into mice were found to induce a humoral and, most importantly, cellular immunity.

Bioluminescence Imaging of Clavibacter michiganensis subsp. michiganensis Infection of Tomato Seeds and Plants ▿

PubMed Central

Xu, Xiulan; Miller, Sally A.; Baysal-Gurel, Fulya; Gartemann, Karl-Heinz; Eichenlaub, Rudolf; Rajashekara, Gireesh

2010-01-01

Clavibacter michiganensis subsp. michiganensis is a Gram-positive bacterium that causes wilting and cankers, leading to severe economic losses in commercial tomato production worldwide. The disease is transmitted from infected seeds to seedlings and mechanically from plant to plant during seedling production, grafting, pruning, and harvesting. Because of the lack of tools for genetic manipulation, very little is known regarding the mechanisms of seed and seedling infection and movement of C. michiganensis subsp. michiganensis in grafted plants, two focal points for application of bacterial canker control measures in tomato. To facilitate studies on the C. michiganensis subsp. michiganensis movement in tomato seed and grafted plants, we isolated a bioluminescent C. michiganensis subsp. michiganensis strain using the modified Tn1409 containing a promoterless lux reporter. A total of 19 bioluminescent C. michiganensis subsp. michiganensis mutants were obtained. All mutants tested induced a hypersensitive response in Mirabilis jalapa and caused wilting of tomato plants. Real-time colonization studies of germinating seeds using a virulent, stable, constitutively bioluminescent strain, BL-Cmm17, showed that C. michiganensis subsp. michiganensis aggregated on hypocotyls and cotyledons at an early stage of germination. In grafted seedlings in which either the rootstock or scion was exposed to BL-Cmm17 via a contaminated grafting knife, bacteria were translocated in both directions from the graft union at higher inoculum doses. These results emphasize the use of bioluminescent C. michiganensis subsp. michiganensis to help better elucidate the C. michiganensis subsp. michiganensis-tomato plant interactions. Further, we demonstrated the broader applicability of this tool by successful transformation of C. michiganensis subsp. nebraskensis with Tn1409::lux. Thus, our approach would be highly useful to understand the pathogenesis of diseases caused by other subspecies of the

Changes in SBPase activity influence photosynthetic capacity, growth, and tolerance to chilling stress in transgenic tomato plants

PubMed Central

Ding, Fei; Wang, Meiling; Zhang, Shuoxin; Ai, Xizhen

2016-01-01

Sedoheptulose-1, 7-bisphosphatase (SBPase) is an important enzyme involved in photosynthetic carbon fixation in the Calvin cycle. Here, we report the impact of changes in SBPase activity on photosynthesis, growth and development, and chilling tolerance in SBPase antisense and sense transgenic tomato (Solanum lycopersicum) plants. In transgenic plants with increased SBPase activity, photosynthetic rates were increased and in parallel an increase in sucrose and starch accumulation was evident. Total biomass and leaf area were increased in SBPase sense plants, while they were reduced in SBPase antisense plants compared with equivalent wild-type tomato plants. Under chilling stress, when compared with plants with decreased SBPase activity, tomato plants with increased SBPase activity were found to be more chilling tolerant as indicated by reduced electrolyte leakage, increased photosynthetic capacity, and elevated RuBP regeneration rate and quantum efficiency of photosystem II. Collectively, our data suggest that higher level of SBPase activity gives an advantage to photosynthesis, growth and chilling tolerance in tomato plants. This work also provides a case study that an individual enzyme in the Calvin cycle may serve as a useful target for genetic engineering to improve production and stress tolerance in crops. PMID:27586456

Acylsucrose-Producing Tomato Plants Forces Bemisia tabaci to Shift Its Preferred Settling and Feeding Site

PubMed Central

Rodríguez-López, Maria Jose; Garzo, Elisa; Bonani, Jean Patrick; Fernández-Muñoz, Rafael; Moriones, Enrique; Fereres, Alberto

2012-01-01

Background The whitefly Bemisia tabaci (Genn.) causes dramatic damage to plants by transmitting yield-limiting virus diseases. Previous studies proved that the tomato breeding line ABL 14-8 was resistant to B. tabaci, the vector of tomato yellow leaf curl disease (TYLCD). This resistance is based on the presence of type IV glandular trichomes and acylsucrose production. These trichomes deter settling and probing of B. tabaci in ABL 14-8, which reduces primary and secondary spread of TYLCD. Methodology/Principal Findings Whitefly settlement preference was evaluated on the adaxial and abaxial leaf surfaces of nearly-isogenic tomato lines with and without B. tabaci-resistance traits, ‘ABL 14-8 and Moneymaker’ respectively, under non-choice and free-choice conditions. In addition, the Electrical Penetration Graph technique was used to study probing and feeding activities of B. tabaci on the adaxial and abaxial leaf surfaces of the same genotypes. B. tabaci preferred to settle on the abaxial than on the adaxial surface of ‘Moneymaker’ leaves, whereas no such preference was observed on ABL 14-8 tomato plants at the ten-leaf growth stage. Furthermore, B. tabaci preferred to feed on the abaxial than on the adaxial leaf surface of ‘Moneymarker’ susceptible tomato plants as shown by a higher number of sustained phloem feeding ingestion events and a shorter time to reach the phloem. However, B. tabaci standard probing and feeding behavior patterns were altered in ABL 14-8 plants and whiteflies were unable to feed from the phloem and spent more time in non-probing activities when exposed to the abaxial leaf surface. Conclusions/Significance The distorted behavior of B. tabaci on ABL 14-8 protects tomato plants from the transmission of phloem-restricted viruses such as Tomato yellow leaf curl virus (TYLCV), and forces whiteflies to feed on the adaxial side of leaves where they feed less efficiently and become more vulnerable to natural enemies. PMID:22427950

The effects of surface-applied jasmonic and salicylic acids on caterpillar growth and damage to tomato plants

Treesearch

Aaron L. Iverson; Louis R. Iverson; Steve Eshita

2001-01-01

We tested the role of salicylic acid (SA) and jasmonic acid (JA) in altering the tomato plant's defense against herbivory by tobacco hornworm. Treatments of SA or JA were topically applied to tomato plants, hornworm consumption was allowed to proceed for 12 days, and harvest analyses were performed Measurements taken included a subjective plant rating (1-10 score...

Plasma membrane potential depolarization and cytosolic calcium flux are early events involved in tomato (Solanum lycopersicon) plant-to-plant communication.

PubMed

Zebelo, Simon A; Matsui, Kenji; Ozawa, Rika; Maffei, Massimo E

2012-11-01

Tomato plants respond to herbivory by emitting volatile organic compounds (VOCs), which are released into the surrounding atmosphere. We analyzed the tomato herbivore-induced VOCs and tested the ability of tomato receiver plants to detect tomato donor volatiles by analyzing early responses, including plasma membrane potential (V(m)) variations and cytosolic calcium ([Ca²⁺](cyt)) fluxes. Receiver tomato plants responded within seconds to herbivore-induced VOCs with a strong V(m) depolarization, which was only partly recovered by fluxing receiver plants with clean air. Among emitted volatiles, we identified by GC-MS some green leaf volatiles (GLVs) such as (E)-2-hexenal, (Z)-3-hexenal, (Z)-3-hexenyl acetate, the monoterpene α-pinene, and the sesquiterpene β-caryophyllene. GLVs were found to exert the stronger V(m) depolarization, when compared to α-pinene and β-caryophyllene. Furthermore, V(m) depolarization was found to increase with increasing GLVs concentration. GLVs were also found to induce a strong [Ca²⁺](cyt) increase, particularly when (Z)-3-hexenyl acetate was tested both in solution and with a gas. On the other hand, α-pinene and β-caryophyllene, which also induced a significant V(m) depolarization with respect to controls, did not exert any significant effect on [Ca²⁺](cyt) homeostasis. Our results show for the first time that plant perception of volatile cues (especially GLVs) from the surrounding environment is mediated by early events, occurring within seconds and involving the alteration of the plasma membrane potential and the [Ca²⁺](cyt) flux. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Apoplastic effectors secreted by two unrelated eukaryotic plant pathogens target the tomato defense protease Rcr3.

PubMed

Song, Jing; Win, Joe; Tian, Miaoying; Schornack, Sebastian; Kaschani, Farnusch; Ilyas, Muhammad; van der Hoorn, Renier A L; Kamoun, Sophien

2009-02-03

Current models of plant-pathogen interactions stipulate that pathogens secrete effector proteins that disable plant defense components known as virulence targets. Occasionally, the perturbations caused by these effectors trigger innate immunity via plant disease resistance proteins as described by the "guard hypothesis." This model is nicely illustrated by the interaction between the fungal plant pathogen Cladosporium fulvum and tomato. C. fulvum secretes a protease inhibitor Avr2 that targets the tomato cysteine protease Rcr3(pim). In plants that carry the resistance protein Cf2, Rcr3(pim) is required for resistance to C. fulvum strains expressing Avr2, thus fulfilling one of the predictions of the guard hypothesis. Another prediction of the guard hypothesis has not yet been tested. Considering that virulence targets are important components of defense, different effectors from unrelated pathogens are expected to evolve to disable the same host target. In this study we confirm this prediction using a different pathogen of tomato, the oomycete Phytophthora infestans that is distantly related to fungi such as C. fulvum. This pathogen secretes an array of protease inhibitors including EPIC1 and EPIC2B that inhibit tomato cysteine proteases. Here we show that, similar to Avr2, EPIC1 and EPIC2B bind and inhibit Rcr3(pim). However, unlike Avr2, EPIC1 and EPIC2B do not trigger hypersensitive cell death or defenses on Cf-2/Rcr3(pim) tomato. We also found that the rcr3-3 mutant of tomato that carries a premature stop codon in the Rcr3 gene exhibits enhanced susceptibility to P. infestans, suggesting a role for Rcr3(pim) in defense. In conclusion, our findings fulfill a key prediction of the guard hypothesis and suggest that the effectors Avr2, EPIC1, and EPIC2B secreted by two unrelated pathogens of tomato target the same defense protease Rcr3(pim). In contrast to C. fulvum, P. infestans appears to have evolved stealthy effectors that carry inhibitory activity without

Assessment of Coriolopsis gallica-treated olive mill wastewater phytotoxicity on tomato plants.

PubMed

Daâssi, Dalel; Sellami, Sahar; Frikha, Fakher; Rodriguez-Couto, Susana; Nasri, Moncef; Mechichi, Tahar

2016-08-01

The aim of the present study was to evaluate the phytotoxicity of olive mill wastewater (OMW) after being treated by the white-rot fungus Coriolopsis gallica. For this, the effect of irrigation with treated OMW (TOMW) and untreated OMW (UOMW) on tomato plants (Lycopersicon esculentum) for 3 weeks was studied. The control plants were irrigated with distilled water. Agronomic tests were performed in pot experiments in a greenhouse using the randomized complete block (RCB) experimental design. The relative leaf height (RLH), as a morphological parameter, and the content of total phenols in the roots and total chlorophyll [Cha + Chb] and reducing sugars in the leaves, as physiological parameters, were selected as responses of the experimental design. The results obtained showed that [Cha + Chb] in the leaves of tomato growth under TOMW was enhanced by 36.3 and 19.4 % compared to the plant growth under UOMW and to the controls, respectively. Also, reducing sugar concentrations were closed to those of the control plants, ranging from 0.424 to 0.678 g/L for the different dilutions tested. However, the plants irrigated with UOMW showed lower reducing sugar concentrations ranging from 0.042 to 0.297g/L. The optimum RLH (0.537) was observed in the plants irrigated with TOMW diluted at (1:4), this value being higher than that observed in the controls (0.438). Our study proved that the irrigation with TOMW significantly improved tomato growth and photosynthesis activity over those irrigated with UOMW. Optimization of TOMW as a fertilizer was obtained for a dilution of 1:4. From the obtained results, it can be concluded that OMW treated by C. gallica holds potential to be used as a fertilizer for tomato plants. Graphical Abstract ᅟ Please provide a caption for the graphical abstract.The graphical abstract is improved and sent as attachment Please replace it.

Detection of the plant parasite Cuscuta reflexa by a tomato cell surface receptor.

PubMed

Hegenauer, Volker; Fürst, Ursula; Kaiser, Bettina; Smoker, Matthew; Zipfel, Cyril; Felix, Georg; Stahl, Mark; Albert, Markus

2016-07-29

Parasitic plants are a constraint on agriculture worldwide. Cuscuta reflexa is a stem holoparasite that infests most dicotyledonous plants. One exception is tomato, which is resistant to C. reflexa We discovered that tomato responds to a small peptide factor occurring in Cuscuta spp. with immune responses typically activated after perception of microbe-associated molecular patterns. We identified the cell surface receptor-like protein CUSCUTA RECEPTOR 1 (CuRe1) as essential for the perception of this parasite-associated molecular pattern. CuRe1 is sufficient to confer responsiveness to the Cuscuta factor and increased resistance to parasitic C. reflexa when heterologously expressed in otherwise susceptible host plants. Our findings reveal that plants recognize parasitic plants in a manner similar to perception of microbial pathogens. Copyright © 2016, American Association for the Advancement of Science.

Transgenic salt-tolerant tomato plants accumulate salt in foliage but not in fruit.

PubMed

Zhang, H X; Blumwald, E

2001-08-01

Transgenic tomato plants overexpressing a vacuolar Na+/H+ antiport were able to grow, flower, and produce fruit in the presence of 200 mM sodium chloride. Although the leaves accumulated high sodium concentrations, the tomato fruit displayed very low sodium content. Contrary to the notion that multiple traits introduced by breeding into crop plants are needed to obtain salt-tolerant plants, the modification of a single trait significantly improved the salinity tolerance of this crop plant. These results demonstrate that with a combination of breeding and transgenic plants it could be possible to produce salt-tolerant crops with far fewer target traits than had been anticipated. The accumulation of sodium in the leaves and not in the fruit demonstrates the utility of such a modification in preserving the quality of the fruit.

Effect of aluminum treatment on proteomes of radicles of seeds derived from Al-treated tomato plants

USDA-ARS?s Scientific Manuscript database

Aluminum (Al) toxicity is a major constraint to plant growth and crop yield in acid soils. Tomato cultivars are especially susceptible to excessive A1 3+ accumulated in the root zone. In this study, tomato plants were grown in a hydroponic culture system supplemented with 50 uM AlK(SO4)2. Seeds harv...

HOW FUNGI INTERACT WITH NEMATODE TO ACTIVATE THE PLANT DEFENCE RESPONSE TO TOMATO PLANTS.

PubMed

Leonetti, P; Costanza, A; Zonno, M C; Molinari, S; Altomare, C

2014-01-01

Management of plant parasitic nematodes with nematode predators, parasites or antagonists is an eco-friendly approach that may avoid the problems arisen by the use of toxic chemicals. Fungi belonging to Trichoderma spp. are well known in literature for their role in control of plant parasitic nematodes. Root-knot nematodes (RKNs), Meloidogyne spp., are obligate parasites that cause the formation of familiar galls on the roots of many cultivated plants. The interaction between the M. incognita motile second stage juveniles (J2s) and the isolate ITEM 908 of Trichoderma harzianum was examined in its effect on the nematode infestation level of susceptible tomato plants. To gain insight into the mechanisms by which ITEM 908 interacts with nematode-infected tomato plants, the expression patterns of the genes PR1 (marker of Salycilic Acid-depending resistance signalling pathway) and JERF3 (marker of the Jasmonic Acid/Ethylene-depending resistance signalling pathway) were detected over time in: i) untreated roots; ii) roots pre-treated with the fungus; iii) roots inoculated with the nematode; iv) pre-treated and inoculated roots. Infestation parameters were checked in untreated plants and plants treated with the fungus to test the effect of the fungus on nematode infestation level and to compare this effect with the expression of the genes PR1 and JERF3, involved in induced resistance.

Salmonella can reach tomato fruits on plants exposed to aerosols formed by rain.

PubMed

Cevallos-Cevallos, Juan M; Gu, Ganyu; Danyluk, Michelle D; Dufault, Nicholas S; van Bruggen, Ariena H C

2012-08-17

Outbreaks of Salmonella enterica have been associated with tomatoes and traced back to production areas but the spread of Salmonella in agricultural fields is still poorly understood. Post-rain Salmonella transfer from a point source to the air and then to tomato plants was evaluated. GFP-labeled kanamycin-resistant S. enterica serovar Typhimurium (10(8)CFU/mL) with and without expression of the rdar morphotype (rough colonies; cells with fimbriae and cellulose) was used as the point source in the center of a rain simulator. Rain intensities of 60 and 110 mm/h were applied for 5, 10, 20, and 30 min. Petri dishes with lactose broth and tomato plants with fruit (50-80 cm high) were placed in the simulator after the rain had ceased. Salmonella recovery from air was maximum (300 CFU/plate) after a rain episode of 60 mm/h for 10 min at distances of at least 85.5 cm above the source and when the rdar morphotype strain was used. Small scale experiments showed that the smooth-colony strain without fimbriae precipitated from the air in significantly higher numbers than the rdar strain. Transfer of aerial Salmonella with the rdar morphotype to tomato fruits on plants followed a beta distribution (2.5950, 4.7393) within the generalized range from 0 to 30 min of rain. Results show for the first time that Salmonella may transfer from rain to the air and contaminate tomato fruits at levels that could possibly be infectious to humans. Copyright © 2012 Elsevier B.V. All rights reserved.

Tomato necrotic streak virus, a novel subgroup 2 ilarvirus

USDA-ARS?s Scientific Manuscript database

A novel plant virus has been identified infecting fresh market tomato plants in south and southeast Florida. The virus causes necrosis of tomato leaves, petioles and stems, and necrotic rings or spots on tomato fruits. Symptomatic tomato plant tissue was used to mechanically inoculate tomato plant...

Determination of rare earth elements in tomato plants by inductively coupled plasma mass spectrometry techniques.

PubMed

Spalla, S; Baffi, C; Barbante, C; Turetta, C; Turretta, C; Cozzi, G; Beone, G M; Bettinelli, M

2009-10-30

In recent years identification of the geographical origin of food has grown more important as consumers have become interested in knowing the provenance of the food that they purchase and eat. Certification schemes and labels have thus been developed to protect consumers and genuine producers from the improper use of popular brand names or renowned geographical origins. As the tomato is one of the major components of what is considered to be the healthy Mediterranean diet, it is important to be able to determine the geographical origin of tomatoes and tomato-based products such as tomato sauce. The aim of this work is to develop an analytical method to determine rare earth elements (RRE) for the control of the geographic origin of tomatoes. The content of REE in tomato plant samples collected from an agricultural area in Piacenza, Italy, was determined, using four different digestion procedures with and without HF. Microwave dissolution with HNO3 + H2O2 proved to be the most suitable digestion procedure. Inductively coupled plasma quadrupole mass spectrometry (ICPQMS) and inductively coupled plasma sector field plasma mass spectrometry (ICPSFMS) instruments, both coupled with a desolvation system, were used to determine the REE in tomato plants in two different laboratories. A matched calibration curve method was used for the quantification of the analytes. The detection limits (MDLs) of the method ranged from 0.03 ng g(-1) for Ho, Tm, and Lu to 2 ng g(-1) for La and Ce. The precision, in terms of relative standard deviation on six replicates, was good, with values ranging, on average, from 6.0% for LREE (light rare earth elements) to 16.5% for HREE (heavy rare earth elements). These detection limits allowed the determination of the very low concentrations of REE present in tomato berries. For the concentrations of REE in tomato plants, the following trend was observed: roots > leaves > stems > berries. Copyright 2009 John Wiley & Sons, Ltd.

Influence of spaceflight on the efficiency of tomatoes quality and plant resistance to viral infection

NASA Astrophysics Data System (ADS)

Dashchenko, Anna; Mishchenko, Lidiya

Tomatoes are an important agricultural crop. The use of plants for life support in long-term space flight advances multiple problems - an adaptation to microgravity and taste. Conditions of microgravity are stressful for plants and they cause them adaptation syndrome to protect and preserve homeostasis (Kordyum, 2010, 2012;. Hasenstein, 1999). Tomatoes are also a product of the diet of astronauts, which is an important part of their life - the regeneration gas environment (photosynthesis), the relaxation factor in psychological people and a powerful antioxidant. In 2007, the tomato seeds, genetically created by scientists from the University of North Carolina, was placed on the International Space Station. But the experiment failed because the seedlings died (Khodakovskaya). Although researchers do not bind this fact with microgravity, it is clear that the study of this factor on plants is rather important. Therefore, the study of the effect of space flight conditions on plant species continues. The aim of our study was to investigate the effect of space flight on tomato plant resistance to viral infection and quality products. Seeds of tomato plants (Lycopersicon esculentum Mill., Sort Podmoskovny early) 6 years (1992-1998) were in terms of long-term space flight on the Russian space station "Mir". Then the seeds germinated in the spring of 2011 and grew up in the Earth's field on the natural infectious background. Part of the plants underwent 5 reproductive phase, resulting in 2011 investigated tomatoes from seed 1st and 5th reproduction, in 2012 - the second and sixth, respectively, and in 2013 - as the second and sixth (sow seeds obtained by us in the Ukraine in 2011.) In our research we used two controls: 1 (stationary control) - plants of the first generation seeds which were not in outer space; 2 - five plants from seed reproduction that exhibited in space and were grown in parallel under the same conditions of the studied plants. Defining of β-carotene and

Oil palm EgCBF3 conferred stress tolerance in transgenic tomato plants through modulation of the ethylene signaling pathway.

PubMed

Ebrahimi, Mortaza; Abdullah, Siti Nor Akmar; Abdul Aziz, Maheran; Namasivayam, Parameswari

2016-09-01

CBF/DREB1 is a group of transcription factors that are mainly involved in abiotic stress tolerance in plants. They belong to the AP2/ERF superfamily of plant-specific transcription factors. A gene encoding a new member of this group was isolated from ripening oil palm fruit and designated as EgCBF3. The oil palm fruit demonstrates the characteristics of a climacteric fruit like tomato, in which ethylene has a major impact on the ripening process. A transgenic approach was used for functional characterization of the EgCBF3, using tomato as the model plant. The effects of ectopic expression of EgCBF3 were analyzed based on expression profiling of the ethylene biosynthesis-related genes, anti-freeze proteins (AFPs), abiotic stress tolerance and plant growth and development. The EgCBF3 tomatoes demonstrated altered phenotypes compared to the wild type tomatoes. Delayed leaf senescence and flowering, increased chlorophyll content and abnormal flowering were the consequences of overexpression of EgCBF3 in the transgenic tomatoes. The EgCBF3 tomatoes demonstrated enhanced abiotic stress tolerance under in vitro conditions. Further, transcript levels of ethylene biosynthesis-related genes, including three SlACSs and two SlACOs, were altered in the transgenic plants' leaves and roots compared to that in the wild type tomato plant. Among the eight AFPs studied in the wounded leaves of the EgCBF3 tomato plants, transcript levels of SlOSM-L, SlNP24, SlPR5L and SlTSRF1 decreased, while expression of the other four, SlCHI3, SlPR1, SlPR-P2 and SlLAP2, were up-regulated. These findings indicate the possible functions of EgCBF3 in plant growth and development as a regulator of ethylene biosynthesis-related and AFP genes, and as a stimulator of abiotic stress tolerance. Copyright © 2016 Elsevier GmbH. All rights reserved.

Does Salicylic Acid (SA) Improve Tolerance to Salt Stress in Plants? A Study of SA Effects On Tomato Plant Growth, Water Dynamics, Photosynthesis, and Biochemical Parameters.

PubMed

Mimouni, Hajer; Wasti, Salma; Manaa, Arafet; Gharbi, Emna; Chalh, Abdellah; Vandoorne, Bertrand; Lutts, Stanley; Ben Ahmed, Hela

2016-03-01

Environmental stresses such as salinity directly impact crop growth, and by extension, world food supply and societal prosperity. It is estimated that over 800 million hectares of land throughout the world are salt-affected. In arid and semi-arid regions, salt concentration can be close to that in the seawater. Hence, there are intensive efforts to improve plant tolerance to salinity and other environmental stressors. Salicylic acid (SA) is an important signal molecule for modulating plant responses to stress. In the present study, we examined, on multiple plant growth related endpoints, whether SA applied through the rooting medium could mitigate the adverse effects of salinity on tomato (Solanum lycopersicum) cv. Marmande. The latter is a hitherto understudied tomato plant from the above perspective; it is a classic variety that produces the large ribbed tomatoes in the Mediterranean and consumed worldwide. We found salt stress negatively affected the growth of cv. Marmande tomato plants. However, the SA-treated plants had greater shoot and root dry mass, leaf area compared to untreated plants when exposed to salt stress. Application of SA restores photosynthetic rates and photosynthetic pigment levels under salt (NaCl) exposure. Leaf water, osmotic potential, stomatal conductance transpiration rate, and biochemical parameters were also ameliorated in SA-treated plants under saline stress conditions. Overall, these data illustrate that SA increases cv. Marmande tomato growth by improving photosynthesis, regulation and balance of osmotic potential, induction of compatible osmolyte metabolism, and alleviating membrane damage. We suggest salicylic acid might be considered as a potential growth regulator to improve tomato plant salinity stress resistance, in the current era of global climate change.

A Tomato Nucleotide Binding Sites-Leucine-Rich Repeat Gene Is Positively Involved in Plant Resistance to Phytophthora infestans.

PubMed

Jiang, Ning; Cui, Jun; Meng, Jun; Luan, Yushi

2018-06-14

The nucleotide binding sites-leucine-rich repeat (NBS-LRR) genes are key regulatory components of plant to pathogens. Phytophthora infestans-inducible coding sequence encoding an NBS-LRR (SpNBS-LRR) protein in tomato (Solanum pimpinellifolium L3708) was cloned and characterized based on our RNA-Seq data and tomato genome. After sequence analysis, SpNBS-LRR was identified as a hydrophilic protein with no transmembrane topological structure and no signal peptide. SpNBS-LRR had a close genetic relationship to RPS2 of Arabidopsis thaliana by phylogenetic analysis. In addition, SpNBS-LRR gene was mainly expressed in root, with low expression observed in leaf and stem. To further investigate the role of SpNBS-LRR in tomato-P. infestans interaction, SpNBS-LRR was introduced in susceptible tomatoes and three transgenic lines with higher expression level of SpNBS-LRR were selected. These transgenic tomato plants that overexpressed SpNBS-LRR displayed greater resistance than wild-type tomato plants after infection with P. infestans, as shown by decreased disease index, lesion diameters, number of necrotic cells, P. infestans abundance, and higher expression levels of the defense-related genes. This information provides insight into SpNBS-LRR involved in the resistance of tomato to P. infestans infection and candidate for breeding to enhance biotic stress-resistance in tomato.

Distribution of Tomato spotted wilt virus in dahlia plants.

PubMed

Asano, S; Hirayama, Y; Matsushita, Y

2017-04-01

Tomato spotted wilt virus (TSWV) causes significant losses in the production of the ornamental plant Dahlia variabilis in Japan. The purpose of this study was to examine the distribution of TSWV in dahlia plants and identify plant parts that can be used in the selection of TSWV-free plants. The distribution of TSWV was investigated using reverse transcriptional polymerase chain reaction (RT-PCR) and tissue blot immunoassay. The detection rate of TSWV in latent infected compound leaves was the highest in the petiole, and it decreased from the veins and rachis to the lamina. The tissue blot immunoassays of the leaflets showed an uneven distribution of TSWV, especially along the edge of the leaf blade. In stems, the detection rate of TSWV was high partway up the stem compared to that in the upper and the lower parts of the stem during the vegetative growth stage. A highly uneven distribution was observed in the bulb. Our results indicated that middle parts of the stem as well as the petioles, rachis, and veins of compound leaves are suitable for detection of TSWV in dahlias. This study is the first to report uneven distribution of TSWV in dahlia plants. In this study, the distribution of Tomato spotted wilt virus (TSWV) in various parts of dahlia plants was investigated for the first time. The distribution of TSWV was uneven in compound leaves, leaflets, stems, and bulbs. The middle parts of the stem or the petiole and leaf veins should be sampled to detect TSWV when selecting healthy plants. © 2017 The Society for Applied Microbiology.

Effect of two solanaceous plants on developmental and population parameters of the tomato leaf miner, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae).

PubMed

Pereyra, Patricia C; Sánchez, Norma E

2006-01-01

Tuta absoluta (Meyrick) is an important tomato pest that also feeds on other host-plants from the Solanceae family. We studied the effect of two cultivated plants, tomato (Lycopersicum esculentum Mill.) and potato Solanum tuberosum L. on the development and populational parameters of T. absoluta related with host-plant suitability. Larval developmental time, pupal weight, mean fecundity and an index of host-plant quality (IPQ = pupal weight / frass weight) were estimated. Age-specific survivorship and fecundity life tables were constructed in the laboratory to evaluate the following populational parameters: net reproductive rate (Ro), intrinsic rate of increase (r) and generation time (T). Larval developmental time was shorter and pupal weight was higher (P < 0.0001) for larvae reared on tomato (P < 0.0001). Mean fecundity was not significantly different on both plants (P = 0.07) and food quality of host-plant was higher for tomato (P = 0.02). Mean population parameters on tomato were: Ro = 48.92; T = 27.98, r = 0.14; and on potato: Ro = 14.43; T = 32.35, r = 0.08. Although results showed that tomato was a more suitable host-plant and had a better nutritional quality than potato, when T. absoluta fed on potato the potential population increase requires attention. Under appropriate climatic conditions, spatial and temporal coincidence between crop and pest, T. absoluta could become a pest for the potato crop.

Potential of Pseudomonas putida PCI2 for the Protection of Tomato Plants Against Fungal Pathogens.

PubMed

Pastor, Nicolás; Masciarelli, Oscar; Fischer, Sonia; Luna, Virginia; Rovera, Marisa

2016-09-01

Tomato is one of the most economically attractive vegetable crops due to its high yields. Diseases cause significant losses in tomato production worldwide. We carried out Polymerase Chain Reaction studies to detect the presence of genes encoding antifungal compounds in the DNA of Pseudomonas putida strain PCI2. We also used liquid chromatography-electrospray tandem mass spectrometry to detect and quantify the production of compounds that increase the resistance of plants to diseases from culture supernatants of PCI2. In addition, we investigated the presence of 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase in PCI2. Finally, PCI2 was used for inoculation of tomato seeds to study its potential biocontrol activity against Fusarium oxysporum MR193. The obtained results showed that no fragments for the encoding genes of hydrogen cyanide, pyoluteorin, 2,4-diacetylphloroglucinol, pyrrolnitrin, or phenazine-1-carboxylic acid were amplified from the DNA of PCI2. On the other hand, PCI2 produced salicylic acid and jasmonic acid in Luria-Bertani medium and grew in a culture medium containing ACC as the sole nitrogen source. We observed a reduction in disease incidence from 53.33 % in the pathogen control to 30 % in tomato plants pre-inoculated with PCI2 as well as increases in shoot and root dry weights in inoculated plants, as compared to the pathogenicity control. This study suggests that inoculation of tomato seeds with P. putida PCI2 increases the resistance of plants to root rot caused by F. oxysporum and that PCI2 produces compounds that may be involved at different levels in increasing such resistance. Thus, PCI2 could represent a non-contaminating management strategy potentially applicable in vegetable crops such as tomato.

Effect on tomato plant and fruit of the application of biopolymer-oregano essential oil coatings.

PubMed

Perdones, Ángela; Tur, Núria; Chiralt, Amparo; Vargas, Maria

2016-10-01

Oregano essential oil (EO) was incorporated into film-forming dispersions (FFDs) based on biopolymers (chitosan and/or methylcellulose) at two different concentrations. The effect of the application of the FFDs was evaluated on tomato plants (cultivar Micro-Tom) at three different stages of development, and on pre-harvest and postharvest applications on tomato fruit. The application of the FFDs at '3 Leaves' stage caused phytotoxic problems, which were lethal when the EO was applied without biopolymers. Even though plant growth and development were delayed, the total biomass and the crop yield were not affected by biopolymer-EO treatments. When the FFDs were applied in the 'Fruit' stage the pre-harvest application of FFDs had no negative effects. All FFDs containing EO significantly reduced the respiration rate of tomato fruit and diminished weight loss during storage. Moreover, biopolymer-EO FFDs led to a decrease in the fungal decay of tomato fruit inoculated with Rhizopus stolonifer spores, as compared with non-treated tomato fruit and those coated with FFDs without EO. The application of biopolymer-oregano essential oil coatings has been proven to be an effective treatment to control R. stolonifer in tomato fruit. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Cross-kingdom effects of plant-plant signaling via volatile organic compounds emitted by tomato (Solanum lycopersicum) plants infested by the greenhouse whitefly (Trialeurodes vaporariorum).

PubMed

Ángeles López, Yesenia Ithaí; Martínez-Gallardo, Norma Angélica; Ramírez-Romero, Ricardo; López, Mercedes G; Sánchez-Hernández, Carla; Délano-Frier, John Paul

2012-11-01

Volatile organic compounds (VOCs) emitted from plants in response to insect infestation can function as signals for the attraction of predatory/parasitic insects and/or repulsion of herbivores. VOCs also may play a role in intra- and inter-plant communication. In this work, the kinetics and composition of VOC emissions produced by tomato (Solanum lycopersicum) plants infested with the greenhouse whitefly Trialeurodes vaporariorum was determined within a 14 days period. The VOC emission profiles varied concomitantly with the duration of whitefly infestation. A total of 36 different VOCs were detected during the experiment, 26 of which could be identified: 23 terpenoids, plus decanal, decane, and methyl salicylate (MeSA). Many VOCs were emitted exclusively by infested plants, including MeSA and 10 terpenoids. In general, individual VOC emissions increased as the infestation progressed, particularly at 7 days post-infestation (dpi). Additional tunnel experiments showed that a 3 days exposure to VOC emissions from whitefly-infested plants significantly reduced infection by a biotrophic bacterial pathogen. Infection of VOC-exposed plants induced the expression of a likely tomato homolog of a methyl salicylate esterase gene, which preceded the expression of pathogenesis-related protein genes. This expression pattern correlated with reduced susceptibility in VOC-exposed plants. The observed cross-kingdom effect of plant-plant signaling via VOCs probably represents a generalized defensive response that contributes to increased plant fitness, considering that resistance responses to whiteflies and biotrophic bacterial pathogens in tomato share many common elements.

Nitrogen nutrition of tomato plant alters leafminer dietary intake dynamics.

PubMed

Coqueret, Victoire; Le Bot, Jacques; Larbat, Romain; Desneux, Nicolas; Robin, Christophe; Adamowicz, Stéphane

2017-05-01

The leafminer Tuta absoluta (Meyrick) is a major pest of the tomato crop and its development rate is known to decline when nitrogen availability for crop growth is limited. Because N limitation reduces plant primary metabolism but enhances secondary metabolism, one can infer that the slow larval development arises from lower leaf nutritive value and/or higher plant defence. As an attempt to study the first alternative, we examined the tomato-T. absoluta interaction in terms of resource supply by leaves and intake by larvae. Tomato plants were raised under controlled conditions on N-sufficient vs. N-limited complete nutrient solutions. Plants were kept healthy or artificially inoculated with larvae for seven days. Serial harvests were taken and the N, C, dry mass and water contents were determined in roots, stems and leaves. Leaf and mine areas were also measured and the N, C, dry mass and water surface densities were calculated in order to characterize the diet of the larvae. The infestation of a specific leaf lessened its local biomass by 8-26%, but this effect was undetectable at the whole plant scale. Infestation markedly increased resource density per unit leaf area (water, dry mass, C and N) suggesting that the insect induced changes in leaf composition. Nitrogen limitation lessened whole plant growth (by 50%) and infested leaflet growth (by 32-44%). It produced opposite effects on specific resource density per unit area, increasing that of dry mass and C while decreasing water and N. These changes were ineffective on insect mining activity, but slowed down larval development. Under N limitation, T. absoluta consumed less water and N but more dry mass and C. The resulting consequences were a 50-70% increase of C:N stoichiometry in their diet and the doubling of faeces excretion. The observed limitation of larval development is therefore consistent with a trophic explanation caused by low N and/or water intakes. Copyright © 2017 Elsevier Ltd. All rights

Bioaccumulation of nickel in tomato plants: risks to human health and agro-environmental impacts.

PubMed

Correia, L; Marrocos, P; Montalván Olivares, D M; Velasco, F G; Luzardo, F H M; Mota de Jesus, R

2018-05-01

Anthropogenic activities such as agriculture, industry, and mining have contributed significantly to the accumulation of heavy metals in the soil, which in turn cause problems to human health and to the environment. The present work aims to study the effects of nickel (Ni) on the development of tomato plants, the risks to human health associated to the consumption of contaminated tomatoes, and the consequences to the environment. The experiment was carried out in greenhouse environment for a period of 120 days, and the plants were cultivated in soils with four different concentrations of Ni: 0, 35, 70, and 105 mg kg -1 . The concentration of nickel in each part (root, stem, leaf, and fruit) of the tomato plant was measured at four different stages of the cycle: 30, 60, 90, and 120 days, by inductively coupled plasma optical emission spectrometer (ICP-OES). At the end of the cycle, the concentration of certain macro- and micronutrients was also determined and related to the corresponding Ni concentration in the soil. The distribution of Ni in the parts of the plant was analyzed from the bioaccumulation factor temporal behavior. Nickel concentrations found in the fruit were too low to pose a risk to human health. As a result of this research, it was verified that soils with nickel concentrations close to 70 mg kg -1 , which is the limit established by the CONAMA resolution (420/2009), may actually represent an optimum concentration value for the development of tomato plants. It also increases productivity per plant and reduces the use of resources such as water and agricultural inputs.

ABA-deficiency results in reduced plant and fruit size in tomato.

PubMed

Nitsch, L; Kohlen, W; Oplaat, C; Charnikhova, T; Cristescu, S; Michieli, P; Wolters-Arts, M; Bouwmeester, H; Mariani, C; Vriezen, W H; Rieu, I

2012-06-15

Abscisic acid (ABA) deficient mutants, such as notabilis and flacca, have helped elucidating the role of ABA during plant development and stress responses in tomato (Solanum lycopersicum L.). However, these mutants have only moderately decreased ABA levels. Here we report on plant and fruit development in the more strongly ABA-deficient notabilis/flacca (not/flc) double mutant. We observed that plant growth, leaf-surface area, drought-induced wilting and ABA-related gene expression in the different genotypes were strongly correlated with the ABA levels and thus most strongly affected in the not/flc double mutants. These mutants also had reduced fruit size that was caused by an overall smaller cell size. Lower ABA levels in fruits did not correlate with changes in auxin levels, but were accompanied by higher ethylene evolution rates. This suggests that in a wild-type background ABA stimulates cell enlargement during tomato fruit growth via a negative effect on ethylene synthesis. Copyright © 2012 Elsevier GmbH. All rights reserved.

Dark Septate Endophytic Fungi Help Tomato to Acquire Nutrients from Ground Plant Material

PubMed Central

Vergara, Carlos; Araujo, Karla E. C.; Urquiaga, Segundo; Schultz, Nivaldo; Balieiro, Fabiano de Carvalho; Medeiros, Peter S.; Santos, Leandro A.; Xavier, Gustavo R.; Zilli, Jerri E.

2017-01-01

Dark septate endophytic (DSE) fungi are facultative biotrophs that associate with hundreds of plant species, contributing to their growth. These fungi may therefore aid in the search for sustainable agricultural practices. However, several ecological functions of DSE fungi need further clarification. The present study investigated the effects of DSE fungi inoculation on nutrient recovery efficiency, nutrient accumulation, and growth of tomato plants fertilized with organic and inorganic N sources. Two experiments were carried out under greenhouse conditions in a randomized blocks design, with five replicates of tomato seedlings grown in pots filled with non-sterile sandy soil. Tomato seedlings (cv. Santa Clara I-5300) inoculated with DSE fungi (isolates A101, A104, and A105) and without DSE fungi (control) were transplanted to pots filled with 12 kg of soil which had previously received finely ground plant material [Canavalia ensiformis (L.)] that was shoot enriched with 0.7 atom % 15N (organic N source experiment) or ammonium sulfate-15N enriched with 1 atom % 15N (mineral N source experiment). Growth indicators, nutrient content, amount of nitrogen (N) in the plant derived from ammonium sulfate-15N or C. ensiformis-15N, and recovery efficiency of 15N, P, and K by plants were quantified 50 days after transplanting. The treatment inoculated with DSE fungi and supplied with an organic N source showed significantly higher recovery efficiency of 15N, P, and K. In addition, the 15N, N, P, K, Ca, Mg, Fe, Mn, and Zn content, plant height, leaf number, leaf area (only for the A104 inoculation), and shoot dry matter increased. In contrast, the only positive effects observed in the presence of an inorganic N source were fertilizer-K recovery efficiency, content of K, and leaf area when inoculated with the fungus A104. Inoculation with A101, A104, and A105 promoted the growth of tomato using organic N source (finely ground C. ensiformis-15N plant material). PMID:29312163

A new approach for in vitro regeneration of tomato plants devoid of exogenous plant growth hormones.

PubMed

Plana, Dagmara; Fuentes, Alejandro; Alvarez, Marta; Lara, Regla M; Alvarez, Félix; Pujol, Merardo

2006-10-01

Many available methodologies for in vitro regeneration of commercial tomato varieties promote not only the production of normal shoots but also individual leaves, shoots without apical meristems and vitrified structures. All these abnormal formations influence and diminish the regeneration efficiency. At the basis of this phenomenon lies callus development. We optimized an alternative procedure by which the regeneration occurs without abnormal shoot formation. The portion including the proximal part of hypocotyls and the radicle was cultured on medium consisting of Murashige and Skoog salts, 4 mg/L thiamine, 100 mg/L mio-inositol and 3% sucrose. After two-three weeks, 60% explants showed adventitious shoot formation. No changes in the morphological characteristics of regenerated plants and fruits were observed as compared with parents. Karyotypic analysis of regenerated plants showed no variations in chromosome number. The optimized procedure offers the advantage of tomato plant regeneration avoiding callus formation, which enables normal plant recovery with an efficiency ranging from 1.45 +/- 0.05 to 2.57 +/- 0.06 shoots per explant in Campbell-28, Amalia, Lignon, and Floradel cultivars.

Effect of coloured shade-nets on plant leaf parameters and tomato fruit quality.

PubMed

Ilić, Zoran S; Milenković, Lidija; Šunić, Ljubomir; Fallik, Elazar

2015-10-01

The concept of photo-selective netting using commercial cultivation practices was studied in a tomato (Solanum lycopersicum 'Vedetta') summer cultivation in south Serbia (under high solar radiation 910 W m(-2) , with a photosynthetic photon flux density of 1661 µmol m(-2) s(-1) ), under four different coloured shade-nets (pearl, red, blue and black) with 40% relative shading. The aim of the study was to determine how different environmental control technologies (coloured shade-nets as screen house or plastic-house integrated with coloured shade-nets) could influence plant parameters, production and quality traits in tomato fruits cultivated in south Serbia (Balkan region). The leaf area index (LAI) ranged from 4.6 to 5.8 in open field and plastic tunnels plants (control) with maximum LAI values of 7.9-8.2 in net houses with red colour nets. Shade-grown leaves generally have higher total chlorophyll and carotenoids content than do control leaves. Pericarp thickness was significantly higher tomatoes grown under pearl (7.215.82 µm), red (7099.00 µm) and blue nets (6802.29 µm) compared to other treatments and to control (6202.48 µm). The highest concentration of lycopene was detected in tomatoes grown in plastic houses integrated with red colour nets (64.9 µg g(-1) fresh weight). The plastic house and open field (control) tomato production had a taste index mean value of 1.09-1.10. This is significantly higher than the values determined for the treatments with different coloured shade-nets. These results show that red and pearl photo-selective nets create optimal growing conditions for the growth of the plant and produce fruits with thicker pericarp, the highest lycopene content, a satisfactory level of taste index and can be further implemented within protected cultivation practices. © 2014 Society of Chemical Industry.

Dissipation of deltamethrin, triazophos, and endosulfan in ready mix formulations in tomato (Lycopersicon esculentum L.) and Egg plant (Solanum melongena L.).

PubMed

Mukherjee, Irani; Kumar, Ashok; Kumar, Aman

2015-09-01

Persistence of delltamethrin, endosulfan, and triazophos in egg plant and tomato was studied following application of two ready mix formulations of insecticides viz. deltametrhin and endosulfan (Cobra 5000; 0.75% deltamethrin + 29.5% endosulfan) and deltamethrin and triazophos (Annaconda Plus; 1% deltamethrin + 35% triazophos) at recommended (1.0 L/ha and double dose 2.0 L/ha). The residues of deltamethrin persisted till 7 and 5 days in tomato and egg plant fruits, respectively, in the ready mix formulation of Cobra 5000 whereas endosulfan persisted till 15 and 10 days in tomato and egg plant fruits, respectively. Dissipation of the insecticides followed first-order kinetics with half-life values of deltamethrin and endosulfan ranged from 2.6 to 4.7 and 1.4 to 1.7 days, respectively, for both the vegetables. In case of combination mix of deltamethrin and triazophos (Annaconda Plus), deltamethrin persisted beyond 5 days in both tomato and egg plant fruits, while triazophos persisted till 10 days in both the vegetables. Residues of deltamethrin and triazophos dissipated with half-life of 2.6-4.2 and 1.7-4.1 days, respectively, on tomato and egg plant fruits. Based on the Codex MRL limits, a safe waiting period of 5 and 3 days is suggested for tomato and egg plant, respectively, for the ready mix formulation of deltamethrin and endosulfan (Cobra 5000), and 5-day waiting period is suggested for tomato and egg plant for the combination mix of deltamethrin and triazophos.

Effect of plant growth-promoting rhizobacteria (PGPRs) on plant growth, yield, and quality of tomato (Lycopersicon esculentum Mill.) under simulated seawater irrigation.

PubMed

Shen, Min; Jun Kang, Yi; Li Wang, Huan; Sheng Zhang, Xiang; Xin Zhao, Qing

2012-01-01

To determine the effects of three PGPRs on plant growth, yield, and quality of tomato under simulated seawater irrigation, a two consecutive seasons' field experiment was conducted in Yancheng Teachers University plot from April to June and August to October, 2011. The results showed that Erwinia persicinus RA2 containing ACC deaminase exhibited the best ability compared with Bacillus pumilus WP8 and Pseudomonas putida RBP1 which had no ACC deaminase activity to enhance marketable yields of fresh and dried fruits in tomato under simulated seawater irrigation especially under HS condition. B. pumilus WP8 had significant effects on improving tomato fruit quality under the conditions of irrigating with 1.0% NaCl solution (MS) and with 2.0% NaCl solution (HS). Na(+) contents were generally accumulated much more in tomato plant mid-shoot leaves than in fruits whatever the salt concentration. More sodium accumulation in leaves of E. persicinus RA2 and B. pumilus WP8 treatments under HS condition were found than in control. E. persicinus RA2 and B. pumilus WP8 can promote tomato growth, improve fruit quality more firmly than P. putida RBP1 during two consecutive seasons. Our study suggested that E. persicinus RA2 and B. pumilus WP8 are considered to be promising PGPR strains which are suited for application in salt marsh planting, ACC deaminase activity was not unique index on screening for PGPRs with the aim of salt stress tolerance, and plant growth promoting activities may be relevant to different growth indices and different stress conditions.

Induction of gentisic acid 5-O-beta-D-xylopyranoside in tomato and cucumber plants infected by different pathogens.

PubMed

Fayos, Joaquín; Bellés, José María; López-Gresa, M Pilar; Primo, Jaime; Conejero, Vicente

2006-01-01

Tomato plants infected with the citrus exocortis viroid exhibited strongly elevated levels of a compound identified as 2,5-dihydroxybenzoic acid (gentisic acid, GA) 5-O-beta-D-xylopyranoside. The compound accumulated early in leaves expressing mild symptoms from both citrus exocortis viroid-infected tomato, and prunus necrotic ringspot virus-infected cucumber plants, and progressively accumulated concomitant with symptom development. The work presented here demonstrates that GA, mainly associated with systemic infections in compatible plant-pathogen interactions [Bellés, J.M., Garro, R., Fayos, J., Navarro, P., Primo, J., Conejero, V., 1999. Gentisic acid as a pathogen-inducible signal, additional to salicylic acid for activation of plant defenses in tomato. Mol. Plant-Microbe Interact. 12, 227-235], is conjugated to xylose. Notably, this result contrasts with those previously found in other plant-pathogen interactions in which phenolics analogues of GA as benzoic or salicylic acids, are conjugated to glucose.

The Role of Tomato WRKY Genes in Plant Responses to Combined Abiotic and Biotic Stresses

PubMed Central

Bai, Yuling; Sunarti, Sri; Kissoudis, Christos; Visser, Richard G. F.; van der Linden, C. G.

2018-01-01

In the field, plants constantly face a plethora of abiotic and biotic stresses that can impart detrimental effects on plants. In response to multiple stresses, plants can rapidly reprogram their transcriptome through a tightly regulated and highly dynamic regulatory network where WRKY transcription factors can act as activators or repressors. WRKY transcription factors have diverse biological functions in plants, but most notably are key players in plant responses to biotic and abiotic stresses. In tomato there are 83 WRKY genes identified. Here we review recent progress on functions of these tomato WRKY genes and their homologs in other plant species, such as Arabidopsis and rice, with a special focus on their involvement in responses to abiotic and biotic stresses. In particular, we highlight WRKY genes that play a role in plant responses to a combination of abiotic and biotic stresses.

A developmentally regulated lipocalin-like gene is overexpressed in Tomato yellow leaf curl virus-resistant tomato plants upon virus inoculation, and its silencing abolishes resistance.

PubMed

Sade, Dagan; Eybishtz, Assaf; Gorovits, Rena; Sobol, Iris; Czosnek, Henryk

2012-10-01

To discover genes involved in tomato resistance to Tomato yellow leaf curl virus (TYLCV), we previously compared cDNA libraries from susceptible (S) and resistant (R) tomato lines. Among the genes preferentially expressed in R plants and upregulated by TYLCV infection was a gene encoding a lipocalin-like protein. This gene was termed Solanum lycopersicum virus resistant/susceptible lipocalin (SlVRSLip). The SlVRSLip structural gene sequence of R and S plants was identical. SlVRSLip was expressed in leaves during a 15-day window starting about 40 days after sowing (20 days after planting). SlVRSLip was upregulated by Bemisia tabaci (the TYLCV vector) feeding on R plant leaves, and even more strongly upregulated following whitefly-mediated TYLCV inoculation. Silencing of SlVRSLip in R plants led to the collapse of resistance upon TYLCV inoculation and to a necrotic response along the stem and petioles accompanied by ROS production. Contrary to previously identified tomato lipocalin gene DQ222981, SlVRSLip was not regulated by cold, nor was it regulated by heat or salt. The expression of SlVRSLip was inhibited in R plants in which the hexose transporter gene LeHT1 was silenced. In contrast, the expression of LeHT1 was not inhibited in SlVRSLip-silenced R plants. Hence, in the hierarchy of the gene network conferring TYLCV resistance, SlVRSLip is downstream of LeHT1. Silencing of another gene involved in resistance, a Permease-I like protein, did not affect the expression of SlVRSLip and LeHT1; expression of the Permease was not affected by silencing SlVRSLip or LeHT1, suggesting that it does not belong to the same network. The triple co-silencing of SlVRSLip, LeHT1 and Permease provoked an immediate cessation of growth of R plants upon infection and the accumulation of large amounts of virus. SlVRSLip is the first lipocalin-like gene shown to be involved in resistance to a plant virus.

Plant growth and resistance promoted by Streptomyces spp. in tomato.

PubMed

Dias, Maila P; Bastos, Matheus S; Xavier, Vanessa B; Cassel, Eduardo; Astarita, Leandro V; Santarém, Eliane R

2017-09-01

Plant Growth Promoting Rhizobacteria (PGPR) represent an alternative to improve plant growth and yield as well as to act as agents of biocontrol. This study characterized isolates of Streptomyces spp. (Stm) as PGPR, determined the antagonism of these isolates against Pectobacterium carotovorum subsp. brasiliensis (Pcb), evaluated the ability of Stm on promoting growth and modulating the defense-related metabolism of tomato plants, and the potential of Stm isolates on reducing soft rot disease in this species. The VOC profile of Stm was also verified. Promotion of plant growth was assessed indirectly through VOC emission and by direct interaction with Stm isolates in the roots. Evaluation of soft rot disease was performed in vitro on plants treated with Stm and challenged with Pcb. Enzymes related to plant defense were then analyzed in plants treated with three selected isolates of Stm, and PM1 was chosen for further Pcb-challenging experiment. Streptomyces spp. isolates displayed characteristics of PGPR. PM3 was the isolate with efficient antagonism against Pcb by dual-culture. Most of the isolates promoted growth of root and shoot of tomato plants by VOC, and PM5 was the isolate that most promoted growth by direct interaction with Stm. Soft rot disease and mortality of plants were significantly reduced when plants were treated with StmPM1. Modulation of secondary metabolism was observed with Stm treatment, and fast response of polyphenoloxidases was detected in plants pretreated with StmPM1 and challenged with Pcb. Peroxidase was significantly activated three days after infection with Pcb in plants pretreated with StmPM1. Results suggest that Streptomyces sp. PM1 and PM5 have the potential to act as PGPR. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Population Growth Parameters of Tuta absoluta (Lepidoptera: Gelechiidae) on Tomato Plant Using Organic Substrate and Biofertilizers

PubMed Central

Razmjou, J.; Naseri, B.; Hassanpour, M.

2017-01-01

The tomato leafminer, Tuta absoluta (Meyrick) is a devastating pest associated with tomato. In this study, effects of tomato plants treated with vermicompost (20, 40, and 60%), humic fertilizer (2, 4 and 6 g/kg soil) and plant growth promoting rhizobacteria (Pseudomonas fluorescens and Bacillus subtilis) were investigated on the life table parameters of T. absoluta in a growth chamber at 25 ± 2 °C, 65 ± 5% RH, and 16:8 (L:D) h. Significant differences were found for the total developmental time, fecundity, and oviposition period of T. absoluta on the treatments tested. The net reproductive rate (R0), intrinsic rate of natural increase (rm), finite rate of increase (λ), mean generation time (T), and doubling time (DT) of T. absoluta were significantly different among treatments tested. We found that in all vermicompost, humic fertilizer and plant growth promoting rhizobacteria treatments, values of R0, rm, and λ were lower than control treatment. However, the lowest values of these parameters were obtained on 2 g/kg humic fertilizer and 40% vermicompost. Furthermore, T. absoluta had longest T and DT values on 2 g/kg humic fertilizer treatment. Data obtained showed that the addition of 2 g/kg humic fertilizer and 40% vermicompost to the growing soil reduced T. absoluta populations in tomato cultures. In addition, these levels of fertilizers improved growth parameters of tomato seedlings (plant height, wet weight, and dry weight) compared with other treatments. These results could be useful in improving the sustainable management of the moth. PMID:28355477

On plant detection of intact tomato fruits using image analysis and machine learning methods.

PubMed

Yamamoto, Kyosuke; Guo, Wei; Yoshioka, Yosuke; Ninomiya, Seishi

2014-07-09

Fully automated yield estimation of intact fruits prior to harvesting provides various benefits to farmers. Until now, several studies have been conducted to estimate fruit yield using image-processing technologies. However, most of these techniques require thresholds for features such as color, shape and size. In addition, their performance strongly depends on the thresholds used, although optimal thresholds tend to vary with images. Furthermore, most of these techniques have attempted to detect only mature and immature fruits, although the number of young fruits is more important for the prediction of long-term fluctuations in yield. In this study, we aimed to develop a method to accurately detect individual intact tomato fruits including mature, immature and young fruits on a plant using a conventional RGB digital camera in conjunction with machine learning approaches. The developed method did not require an adjustment of threshold values for fruit detection from each image because image segmentation was conducted based on classification models generated in accordance with the color, shape, texture and size of the images. The results of fruit detection in the test images showed that the developed method achieved a recall of 0.80, while the precision was 0.88. The recall values of mature, immature and young fruits were 1.00, 0.80 and 0.78, respectively.

Tomato ring spot virus

USDA-ARS?s Scientific Manuscript database

Tomato ringspot disease, caused by Tomato ringspot virus (TmRSV), is associated with the presence of dagger nematodes, the major vectors of Tomato ringspot virus (TmRSV). This virus is endemic and widely distributed in North America, as well as many parts of the world. Infected plants develop yello...

Interrelated responses of tomato plants and the leaf miner Tuta absoluta to nitrogen supply.

PubMed

Larbat, R; Adamowicz, S; Robin, C; Han, P; Desneux, N; Le Bot, J

2016-05-01

Plant-insect interactions are strongly modified by environmental factors. This study evaluates the influence of nitrogen fertilisation on the tomato (Solanum lycopersicum L.) cv. Santa clara and the leafminer (Tuta absoluta (Meyrick), Lepidoptera: Gelechiidae). Greenhouse-grown tomato plants were fed hydroponically on a complete nutrient solution containing either a high nitrogen concentration (HN) sustaining maximum growth or a low nitrogen concentration (LN) limiting plant growth. Insect-free plants were compared with plants attacked by T. absoluta. Seven and 14 days after artificial oviposition leading to efficacious hatching and larvae development, we measured total carbon, nitrogen and soluble protein as well as defence compounds (phenolics, glycoalkaloids, polyphenol oxidase activity) in the HN versus LN plants. Only in the HN treatment did T. absoluta infestation slightly impair leaf growth and induce polyphenol oxidase (PPO) activity in the foliage. Neither the concentration of phenolic compounds and proteins nor the distribution of nitrogen within the plant was affected by T. absoluta infestation. In contrast, LN nutrition impaired T. absoluta-induced PPO activity. It decreased protein and total nitrogen concentration of plant organs and enhanced the accumulation of constitutive phenolics and tomatine. Moreover, LN nutrition impaired T. absoluta development by notably decreasing pupal weight and lengthening the development period from egg to adult. Adjusting the level of nitrogen nutrition may thus be a means of altering the life cycle of T. absoluta. This study provides a comprehensive dataset concerning interrelated responses of tomato plants and T. absoluta to nitrogen nutrition. © 2015 German Botanical Society and The Royal Botanical Society of the Netherlands.

Carnivore Attractant or Plant Elicitor? Multifunctional Roles of Methyl Salicylate Lures in Tomato Defense.

PubMed

Rowen, Elizabeth; Gutensohn, Michael; Dudareva, Natalia; Kaplan, Ian

2017-06-01

Synthetic plant volatile lures attract natural enemies, but may have non-target effects due to the multifunctional nature of volatile signals. For example, methyl salicylate (MeSA) is used to attract predators, yet also serves as a signaling hormone involved in plant pathogen defense. We investigated the consequences of deploying MeSA lures to attract predators for tomato (Solanum lycopersicum) defense against herbivores. To understand the spatial distribution of the lure's effect, we exposed tomatoes in the field to MeSA along a linear distance gradient and induced defenses by simulating feeding by hornworm caterpillars in a fully crossed factorial design (+/- MeSA, +/- herbivory). Subsequently, we analyzed activity of several defensive proteins (protease inhibitors, polyphenol oxidase, peroxidase), development of hornworm larvae (Manduca sexta), growth of fungal pathogens (Cladosporium and Alternaria), and attractiveness to herbivores and predators. Overall, MeSA-exposed plants were more resistant to both insects and pathogens. Secondary pathogen infection was reduced by 25% in MeSA exposed plants, possibly due to elevated polyphenol oxidase activity. Interestingly, we found that lures affected plant pathogen defenses equivalently across all distances (up to 4 m away) indicating that horizontal diffusion of a synthetic volatile may be greater than previously assumed. While thrips avoided colonizing hornworm- damaged tomato plants, this induced resistance was not observed upon pre-exposure to MeSA, suggesting that MeSA suppresses the repellant effect induced by herbivory. Thus, using MeSA lures in biological control may inadvertently protect crops from pathogens, but has mixed effects on plant resistance to insect herbivores.

Population Growth Parameters of Tuta absoluta (Lepidoptera: Gelechiidae) on Tomato Plant Using Organic Substrate and Biofertilizers.

PubMed

Mohamadi, P; Razmjou, J; Naseri, B; Hassanpour, M

2017-01-01

The tomato leafminer, Tuta absoluta (Meyrick) is a devastating pest associated with tomato. In this study, effects of tomato plants treated with vermicompost (20, 40, and 60%), humic fertilizer (2, 4 and 6 g/kg soil) and plant growth promoting rhizobacteria (Pseudomonas fluorescens and Bacillus subtilis) were investigated on the life table parameters of T. absoluta in a growth chamber at 25 ± 2 °C, 65 ± 5% RH, and 16:8 (L:D) h. Significant differences were found for the total developmental time, fecundity, and oviposition period of T. absoluta on the treatments tested. The net reproductive rate (R0), intrinsic rate of natural increase (rm), finite rate of increase (λ), mean generation time (T), and doubling time (DT) of T. absoluta were significantly different among treatments tested. We found that in all vermicompost, humic fertilizer and plant growth promoting rhizobacteria treatments, values of R0, rm, and λ were lower than control treatment. However, the lowest values of these parameters were obtained on 2 g/kg humic fertilizer and 40% vermicompost. Furthermore, T. absoluta had longest T and DT values on 2 g/kg humic fertilizer treatment. Data obtained showed that the addition of 2 g/kg humic fertilizer and 40% vermicompost to the growing soil reduced T. absoluta populations in tomato cultures. In addition, these levels of fertilizers improved growth parameters of tomato seedlings (plant height, wet weight, and dry weight) compared with other treatments. These results could be useful in improving the sustainable management of the moth. © The Author 2017. Published by Oxford University Press on behalf of the Entomological Society of America.

Attraction of Three Mirid Predators to Tomato Infested by Both the Tomato Leaf Mining Moth Tuta absoluta and the Whitefly Bemisia tabaci.

PubMed

Silva, Diego B; Bueno, Vanda H P; Van Loon, Joop J A; Peñaflor, Maria Fernanda G V; Bento, José Maurício S; Van Lenteren, Joop C

2018-01-01

Plants emit volatile compounds in response to insect herbivory, which may play multiple roles as defensive compounds and mediators of interactions with other plants, microorganisms and animals. Herbivore-induced plant volatiles (HIPVs) may act as indirect plant defenses by attracting natural enemies of the attacking herbivore. We report here the first evidence of the attraction of three Neotropical mirid predators (Macrolophus basicornis, Engytatus varians and Campyloneuropsis infumatus) toward plants emitting volatiles induced upon feeding by two tomato pests, the leaf miner Tuta absoluta and the phloem feeder Bemisia tabaci, in olfactometer bioassays. Subsequently, we compared the composition of volatile blends emitted by insect-infested tomato plants by collecting headspace samples and analyzing them with GC-FID and GC-MS. Egg deposition by T. absoluta did not make tomato plants more attractive to the mirid predators than uninfested tomato plants. Macrolophus basicornis is attracted to tomato plants infested with either T. absoluta larvae or by a mixture of B. tabaci eggs, nymphs and adults. Engytatus varians and C. infumatus responded to volatile blends released by tomato plants infested with T. absoluta larvae over uninfested plants. Also, multiple herbivory by T. absoluta and B. tabaci did not increase the attraction of the mirids compared to infestation with T. absoluta alone. Terpenoids represented the most important class of compounds in the volatile blends and there were significant differences between the volatile blends emitted by tomato plants in response to attack by T. absoluta, B. tabaci, or by both insects. We, therefore, conclude that all three mirids use tomato plant volatiles to find T. absoluta larvae. Multiple herbivory did neither increase, nor decrease attraction of C. infumatus, E. varians and M. basicornis. By breeding for higher rates of emission of selected terpenes, increased attractiveness of tomato plants to natural enemies may

Proteome modification in tomato plants upon long-term aluminum treatment

USDA-ARS?s Scientific Manuscript database

This study aimed to identify the aluminum (Al)-induced proteomes in tomato (Solanum lycopersicum, “Micro-Tom”) after long-term exposure to the stress factor. Plants were treated in Magnavaca’s solution (pH 4.5) supplemented with 7.5 uM Al3+ ion activity over a 4 month period beginning at the emergen...

Control efficiency and expressions of resistance genes in tomato plants treated with ε-poly-l-lysine against Botrytis cinerea.

PubMed

Sun, Guangzheng; Wang, Han; Shi, Beibei; Shangguan, Nini; Wang, Yang; Ma, Qing

2017-11-01

The antifungal properties and the induction of resistance by ε-poly-l-lysine (ε-PL) were examined to reveal its potential in protecting tomato plants against Botrytis cinerea. As presented herein, ε-PL at 1200mg/L was found to have optimal in vitro antifungal activities, achieving an inhibition rate of 94.96%. In first-year field tests, ε-PL (1200mg/L) had a control effect of up to 79.07% against tomato grey mould. Similar results were obtained in the second year. In greenhouse experiments, ε-PL was observed to effectively reduce leaf infection, with an observed control rate at 89.22%. To define the molecular-genetic mechanisms, we compared the gene expression under four different conditions: sterile water sprayed plants (Control), Botrytis-infected plants (Inf), ε-PL-treated plants (ε-PL) and ε-PL-treated+infected plants (ε-PL+Inf). Quantitative PCR analysis at 36h after inoculation revealed that ε-PL+Inf plants exhibited significant expression and priming of several key Botrytis-induced genes in tomato. The results indicate that ε-PL promoted plant capacity of tomato to activate defense mechanisms upon pathogen attack. In total, these findings revealed that ε-PL should be an excellent biocontrol agent candidate that combined direct antifungal activity against B. cinerea and plant resistance capacity. Copyright © 2017. Published by Elsevier Inc.

Real time expression of ACC oxidase and PR-protein genes mediated by Methylobacterium spp. in tomato plants challenged with Xanthomonas campestris pv. vesicatoria.

PubMed

Yim, W J; Kim, K Y; Lee, Y W; Sundaram, S P; Lee, Y; Sa, T M

2014-07-15

Biotic stress like pathogenic infection increases ethylene biosynthesis in plants and ethylene inhibitors are known to alleviate the severity of plant disease incidence. This study aimed to reduce the bacterial spot disease incidence in tomato plants caused by Xanthomonas campestris pv. vesicatoria (XCV) by modulating stress ethylene with 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity of Methylobacterium strains. Under greenhouse condition, Methylobacterium strains inoculated and pathogen challenged tomato plants had low ethylene emission compared to pathogen infected ones. ACC accumulation and ACC oxidase (ACO) activity with ACO related gene expression increased in XCV infected tomato plants over Methylobacterium strains inoculated plants. Among the Methylobacterium spp., CBMB12 resulted lowest ACO related gene expression (1.46 Normalized Fold Expression), whereas CBMB20 had high gene expression (3.42 Normalized Fold Expression) in pathogen challenged tomato. But a significant increase in ACO gene expression (7.09 Normalized Fold Expression) was observed in the bacterial pathogen infected plants. In contrast, Methylobacterium strains enhanced β-1,3-glucanase and phenylalanine ammonia-lyase (PAL) enzyme activities in pathogen challenged tomato plants. The respective increase in β-1,3-glucanase related gene expressions due to CBMB12, CBMB15, and CBMB20 strains were 66.3, 25.5 and 10.4% higher over pathogen infected plants. Similarly, PAL gene expression was high with 0.67 and 0.30 Normalized Fold Expression, in pathogen challenged tomato plants inoculated with CBMB12 and CBMB15 strains. The results suggest that ethylene is a crucial factor in bacterial spot disease incidence and that methylobacteria with ACC deaminase activity can reduce the disease severity with ultimate pathogenesis-related protein increase in tomato. Copyright © 2014 Elsevier GmbH. All rights reserved.

Oral immunization of mice using transgenic tomato fruit expressing VP1 protein from enterovirus 71.

PubMed

Chen, Hsuan-Fu; Chang, Meng-Huei; Chiang, Bor-Luen; Jeng, Shih-Tong

2006-04-05

Enterovirus 71 (EV71) causes seasonal epidemics of hand-foot-and-mouth disease associated with fatal neurological complications in young children, and several major outbreaks have occurred recently. This study developed an effective antiviral agent by transforming the gene for VP1 protein, a previously defined epitope and also a coat protein of EV71, into tomato plant. VP1 protein was first fused with sorting signals to enable it to be retained in the endoplasmic reticulum of tomato plant, and its expression level increased to 27 microg/g of fresh tomato fruit. Transgenic tomato fruit expressing VP1 protein was then used as an oral vaccine, and the development of VP1-specific fecal IgA and serum IgG were observed in BALB/c mice. Additionally, serum from mice fed transgenic tomato could neutralize the infection of EV71 to rhabdomyosarcoma cells, indicating that tomato fruit expressing VP1 was successful in orally immunizing mice. Moreover, the proliferation of spleen cells from orally immunized mice was stimulated by VP1 protein, and provided further evidence of both humoral and cellular immunity. Results of this study not only demonstrate the feasibility of using transgenic tomato as an oral vaccine to generate protective immunity in mice against EV71, but also suggest the probability of enterovirus vaccine development.

Distinct physiological responses of tomato and cucumber plants in silicon-mediated alleviation of cadmium stress

PubMed Central

Wu, Jiawen; Guo, Jia; Hu, Yanhong; Gong, Haijun

2015-01-01

The alleviative effects of silicon (Si) on cadmium (Cd) toxicity were investigated in cucumber (Cucumis sativus L.) and tomato (Solanum lycopersicum L.) grown hydroponically. The growth of both plant species was inhibited by 100 μM Cd, but Si application counteracted the adverse effects on growth. Si application significantly decreased the Cd concentrations in shoots of both species and roots of cucumber. The root-to-shoot transport of Cd was depressed by added Si in tomato whereas it was increased by added Si in cucumber. The total content of organic acids was decreased in tomato leaves but increased in cucumber roots and leaves by Si application under Cd stress. Si application also increased the cell wall polysaccharide levels in the roots of both species under Cd toxicity. Si-mediated changes in levels of organic acids and cell wall polysaccharides might contribute to the differences in Cd transport in the two species. In addition, Si application also mitigated Cd-induced oxidative damage in both species. The results indicate that there were different mechanisms for Si-mediated decrease in shoot Cd accumulation: in tomato, Si supply decreased root-to-shoot Cd transport; whereas in cucumber, Si supply reduced the Cd uptake by roots. It is suggested that Si-mediated Cd tolerance is associated with different physiological responses in tomato and cucumber plants. PMID:26136764

Expression of the human hepatitis B virus large surface antigen gene in transgenic tomato plants.

PubMed

Lou, Xiao-Ming; Yao, Quan-Hong; Zhang, Zhen; Peng, Ri-He; Xiong, Ai-Sheng; Wang, Hua-Kun

2007-04-01

The original hepatitis B virus (HBV) large surface antigen gene was synthesized. In order to optimize the expression of this gene in tomato plants, the tobacco pathogenesis-related protein S signal peptide was fused to the 5' end of the modified gene and the sequence encoding amino acids S, E, K, D, E, and L was placed at the 3' end. The gene encoding the modified HBV large surface antigen under the control of a fruit-specific promoter was constructed and expressed in transgenic tomato plants. The expression of the antigen from transgenic plants was confirmed by PCR and reverse transcriptase PCR. Enzyme-linked immunoassays using a monoclonal antibody directed against human serum-derived HBsAg revealed that the maximal level of HBsAg was about 0.02% of the soluble protein in transgenic tomato fruit. The amount of HBsAg in mature fruits was found to be 65- to 171-fold larger than in small or medium fruits and leaf tissues. Examination of transgenic plant samples by transmission electron microscopy proved that HBsAg had been expressed and had accumulated. The HBsAg protein was capable of assembling into capsomers and virus-like particles. To our knowledge, this is the first time the HBV large surface antigen has been expressed in plants. This work suggests the possibility of producing a new alternative vaccine for human HBV.

Organic Matter Application Can Reduce Copper Toxicity in Tomato Plants

ERIC Educational Resources Information Center

Campbell, Brian

2010-01-01

Copper fungicides and bactericides are often used in tomato cultivation and can cause toxic Cu levels in soils. In order to combat this, organic matter can be applied to induce chelation reactions and form a soluble complex by which much of the Cu can leach out of the soil profile or be taken up safely by plants. Organic acids such as citric,…

A Bacillus subtilis Sensor Kinase Involved in Triggering Biofilm Formation on the Roots of Tomato Plants

PubMed Central

Chen, Yun; Cao, Shugeng; Chai, Yunrong; Clardy, Jon; Kolter, Roberto; Guo, Jian-hua; Losick, Richard

2012-01-01

SUMMARY The soil bacterium Bacillus subtilis is widely used in agriculture as a biocontrol agent able to protect plants from a variety of pathogens. Protection is thought to involve the formation of bacterial communities - biofilms - on the roots of the plants. Here we used confocal microscopy to visualize biofilms on the surface of the roots of tomato seedlings and demonstrated that biofilm formation requires genes governing the production of the extracellular matrix that holds cells together. We further show that biofilm formation was dependent on the sensor histidine kinase KinD and in particular on an extracellular CACHE domain implicated in small molecule sensing. Finally, we report that exudates of tomato roots strongly stimulated biofilm formation ex planta and that an abundant small molecule in the exudates, l-malic acid, was able to stimulate biofilm formation at high concentrations in a manner that depended on the KinD CACHE domain. We propose that small signaling molecules released by the roots of tomato plants are directly or indirectly recognized by KinD, triggering biofilm formation. PMID:22716461

Melatonin enhances thermotolerance by promoting cellular protein protection in tomato plants.

PubMed

Xu, Wen; Cai, Shu-Yu; Zhang, Yun; Wang, Yu; Ahammed, Golam Jalal; Xia, Xiao-Jian; Shi, Kai; Zhou, Yan-Hong; Yu, Jing-Quan; Reiter, Russel J; Zhou, Jie

2016-11-01

Melatonin is a pleiotropic signaling molecule that provides physiological protection against diverse environmental stresses in plants. Nonetheless, the mechanisms for melatonin-mediated thermotolerance remain largely unknown. Here, we report that endogenous melatonin levels increased with a rise in ambient temperature and that peaked at 40°C. Foliar pretreatment with an optimal dose of melatonin (10 μmol/L) or the overexpression of N-acetylserotonin methyltransferase (ASMT) gene effectively ameliorated heat-induced photoinhibition and electrolyte leakage in tomato plants. Both exogenous melatonin treatment and endogenous melatonin manipulation by overexpression of ASMT decreased the levels of insoluble and ubiquitinated proteins, but enhanced the expression of heat-shock proteins (HSPs) to refold denatured and unfolded proteins under heat stress. Meanwhile, melatonin also induced expression of several ATG genes and formation of autophagosomes to degrade aggregated proteins under the same stress. Proteomic profile analyses revealed that protein aggregates for a large number of biological processes accumulated in wild-type plants. However, exogenous melatonin treatment or overexpression of ASMT reduced the accumulation of aggregated proteins. Aggregation responsive proteins such as HSP70 and Rubisco activase were preferentially accumulated and ubiquitinated in wild-type plants under heat stress, while melatonin mitigated heat stress-induced accumulation and ubiquitination of aggregated proteins. These results suggest that melatonin promotes cellular protein protection through induction of HSPs and autophagy to refold or degrade denatured proteins under heat stress in tomato plants. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Response of nitrogen metabolism to boron toxicity in tomato plants.

PubMed

Cervilla, L M; Blasco, B; Ríos, J J; Rosales, M A; Rubio-Wilhelmi, M M; Sánchez-Rodríguez, E; Romero, L; Ruiz, J M

2009-09-01

Boron (B) toxicity has become important in areas close to the Mediterranean Sea where intensive agriculture has been developed. The objective of this research was to study the effects of B toxicity (0.5 mM and 2.0 mM B) on nitrogen (N) assimilation of two tomato cultivars that are often used in these areas. Leaf biomass, relative leaf growth rate (RGR(L)), concentration of B, nitrate (NO(3) (-)), ammonium (NH(4) (+)), organic N, amino acids and soluble proteins, as well as nitrate reductase (NR), nitrite reductase (NiR), glutamine synthase (GS), glutamate synthetase (GOGAT) and glutamate dehydrogenase (GDH) activities were analysed in leaves. Boron toxicity significantly decreased leaf biomass, RGR(L), organic N, soluble proteins, and NR and NiR activities. The lowest NO(3) (-) and NH(4) (+) concentration in leaves was recorded when plants were supplied with 2.0 mM B in the root medium. Total B, amino acids, activities of GS, GOGAT and GDH increased under B toxicity. Data from the present study prove that B toxicity causes inhibition of NO(3) (-) reduction and increases NH(4) (+) assimilation in tomato plants.

Exogenous Melatonin Mitigates Acid Rain Stress to Tomato Plants through Modulation of Leaf Ultrastructure, Photosynthesis and Antioxidant Potential.

PubMed

Debnath, Biswojit; Hussain, Mubasher; Irshad, Muhammad; Mitra, Sangeeta; Li, Min; Liu, Shuang; Qiu, Dongliang

2018-02-11

Acid rain (AR) is a serious global environmental issue causing physio-morphological changes in plants. Melatonin, as an indoleamine molecule, has been known to mediate many physiological processes in plants under different kinds of environmental stress. However, the role of melatonin in acid rain stress tolerance remains inexpressible. This study investigated the possible role of melatonin on different physiological responses involving reactive oxygen species (ROS) metabolism in tomato plants under simulated acid rain (SAR) stress. SAR stress caused the inhibition of growth, damaged the grana lamella of the chloroplast, photosynthesis, and increased accumulation of ROS and lipid peroxidation in tomato plants. To cope the detrimental effect of SAR stress, plants under SAR condition had increased both enzymatic and nonenzymatic antioxidant substances compared with control plants. But such an increase in the antioxidant activities were incapable of inhibiting the destructive effect of SAR stress. Meanwhile, melatonin treatment increased SAR-stress tolerance by repairing the grana lamella of the chloroplast, improving photosynthesis and antioxidant activities compared with those in SAR-stressed plants. However, these possible effects of melatonin are dependent on concentration. Moreover, our study suggests that 100-μM melatonin treatment improved the SAR-stress tolerance by increasing photosynthesis and ROS scavenging antioxidant activities in tomato plants.

Effect of Aluminum Treatment on Proteomes of Radicles of Seeds Derived from Al-Treated Tomato Plants

PubMed Central

Okekeogbu, Ikenna; Ye, Zhujia; Sangireddy, Sasikiran Reddy; Li, Hui; Bhatti, Sarabjit; Hui, Dafeng; Zhou, Suping; Howe, Kevin J.; Fish, Tara; Yang, Yong; Thannhauser, Theodore W.

2014-01-01

Aluminum (Al) toxicity is a major constraint to plant growth and crop yield in acid soils. Tomato cultivars are especially susceptible to excessive Al3+ accumulated in the root zone. In this study, tomato plants were grown in a hydroponic culture system supplemented with 50 µM AlK(SO4)2. Seeds harvested from Al-treated plants contained a significantly higher Al content than those grown in the control hydroponic solution. In this study, these Al-enriched tomato seeds (harvested from Al-treated tomato plants) were germinated in 50 µM AlK(SO4)2 solution in a homopiperazine-1,4-bis(2-ethanesulfonic acid) buffer (pH 4.0), and the control solution which contained the buffer only. Proteomes of radicles were analyzed quantitatively by mass spectrometry employing isobaric tags for relative and absolute quantitation (iTRAQ®). The proteins identified were assigned to molecular functional groups and cellular metabolic pathways using MapMan. Among the proteins whose abundance levels changed significantly were: a number of transcription factors; proteins regulating gene silencing and programmed cell death; proteins in primary and secondary signaling pathways, including phytohormone signaling and proteins for enhancing tolerance to abiotic and biotic stress. Among the metabolic pathways, enzymes in glycolysis and fermentation and sucrolytic pathways were repressed. Secondary metabolic pathways including the mevalonate pathway and lignin biosynthesis were induced. Biological reactions in mitochondria seem to be induced due to an increase in the abundance level of mitochondrial ribosomes and enzymes in the TCA cycle, electron transport chains and ATP synthesis. PMID:28250376

Design And Control Of Agricultural Robot For Tomato Plants Treatment And Harvesting

NASA Astrophysics Data System (ADS)

Sembiring, Arnes; Budiman, Arif; Lestari, Yuyun D.

2017-12-01

Although Indonesia is one of the biggest agricultural country in the world, implementation of robotic technology, otomation and efficiency enhancement in agriculture process hasn’t extensive yet. This research proposed a low cost agricultural robot architecture. The robot could help farmer to survey their farm area, treat the tomato plants and harvest the ripe tomatoes. Communication between farmer and robot was facilitated by wireless line using radio wave to reach wide area (120m radius). The radio wave was combinated with Bluetooth to simplify the communication between robot and farmer’s Android smartphone. The robot was equipped with a camera, so the farmers could survey the farm situation through 7 inch monitor display real time. The farmers controlled the robot and arm movement through an user interface in Android smartphone. The user interface contains control icons that allow farmers to control the robot movement (formard, reverse, turn right and turn left) and cut the spotty leaves or harvest the ripe tomatoes.

Refuse derived soluble bio-organics enhancing tomato plant growth and productivity.

PubMed

Sortino, Orazio; Dipasquale, Mauro; Montoneri, Enzo; Tomasso, Lorenzo; Perrone, Daniele G; Vindrola, Daniela; Negre, Michele; Piccone, Giuseppe

2012-10-01

Municipal bio-refuse (CVD), containing kitchen wastes, home gardening residues and public park trimmings, was treated with alkali to yield a soluble bio-organic fraction (SBO) and an insoluble residue. These materials were characterized using elemental analysis, potentiometric titration, and 13C NMR spectroscopy, and then applied as organic fertilizers to soil for tomato greenhouse cultivation. Their performance was compared with a commercial product obtained from animal residues. Plant growth, fruit yield and quality, and soil and leaf chemical composition were the selected performance indicators. The SBO exhibited the best performance by enhancing leaf chlorophyll content, improving plant growth and fruit ripening rate and yield. No product performance-chemical composition relationship could be assessed. Solubility could be one reason for the superior performance of SBO as a tomato growth promoter. The enhancement of leaf chlorophyll content is discussed to identify a possible link with the SBO photosensitizing properties that have been demonstrated in other work, and thus with photosynthetic performance. Copyright © 2012 Elsevier Ltd. All rights reserved.

Insecticidal Effects on the Spatial Progression of Tomato Yellow Leaf Curl Virus and Movement of Its Whitefly Vector in Tomato.

PubMed

Dempsey, M; Riley, D G; Srinivasan, R

2017-06-01

Commercial management of whitefly-transmitted Tomato yellow leaf curl virus (TYLCV) typically relies on insecticide control of whitefly vectors as a first line of defense. We quantified this effect in crop tunnel studies, with validation in a tomato field setting. Tomato yellow leaf curl virus-infected and Bemisia tabaci (Gennadius)-infested source plants were planted at the beginning of tunneled rows to serve as inoculum source, so that movement of whiteflies and TYLCV symptoms could be tracked down the length of the tunnel over time. Tunnel study results showed that proximity to the source plant was a more important factor than insecticide treatments. Insecticide-treated tomato transplants did tend to suppress whitefly incidence and slowed TYLCV movement in comparison with the untreated check; however, tomato plants planted closer to the source plant had higher incidence of whiteflies and TYLCV infection, regardless of treatment. In a large tomato plot study with a controlled inoculum source, insecticide treatments significantly reduced the spread of TYLCV. When uninhibited by insecticide treatment, 80% of the TYLCV spread was restricted to <15 m from the source plant (<11 m in the validation study), with insecticide treatment generally reducing the distance and magnitude of this spread. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Plant Pathogen-Induced Water-Soaking Promotes Salmonella enterica Growth on Tomato Leaves

PubMed Central

Potnis, Neha; Colee, James; Jones, Jeffrey B.

2015-01-01

Plant pathogen infection is a critical factor for the persistence of Salmonella enterica on plants. We investigated the mechanisms responsible for the persistence of S. enterica on diseased tomato plants by using four diverse bacterial spot Xanthomonas species that differ in disease severities. Xanthomonas euvesicatoria and X. gardneri infection fostered S. enterica growth, while X. perforans infection did not induce growth but supported the persistence of S. enterica. X. vesicatoria-infected leaves harbored S. enterica populations similar to those on healthy leaves. Growth of S. enterica was associated with extensive water-soaking and necrosis in X. euvesicatoria- and X. gardneri-infected plants. The contribution of water-soaking to the growth of S. enterica was corroborated by an increased growth of populations on water-saturated leaves in the absence of a plant pathogen. S. enterica aggregates were observed with bacterial spot lesions caused by either X. euvesicatoria or X. vesicatoria; however, more S. enterica aggregates formed on X. euvesicatoria-infected leaves as a result of larger lesion sizes per leaf area and extensive water-soaking. Sparsely distributed lesions caused by X. vesicatoria infection do not support the overall growth of S. enterica or aggregates in areas without lesions or water-soaking; S. enterica was observed as single cells and not aggregates. Thus, pathogen-induced water-soaking and necrosis allow S. enterica to replicate and proliferate on tomato leaves. The finding that the pathogen-induced virulence phenotype affects the fate of S. enterica populations in diseased plants suggests that targeting of plant pathogen disease is important in controlling S. enterica populations on plants. PMID:26386057

A trial of production of the plant-derived high-value protein in a plant factory: photosynthetic photon fluxes affect the accumulation of recombinant miraculin in transgenic tomato fruits.

PubMed

Kato, Kazuhisa; Maruyama, Shinichiro; Hirai, Tadayoshi; Hiwasa-Tanase, Kyoko; Mizoguchi, Tsuyoshi; Goto, Eiji; Ezura, Hiroshi

2011-08-01

One of the ultimate goals of plant science is to test a hypothesis obtained by basic science and to apply it to agriculture and industry. A plant factory is one of the ideal systems for this trial. Environmental factors affect both plant yield and the accumulation of recombinant proteins for industrial applications within transgenic plants. However, there have been few reports studying plant productivity for recombinant protein in closed cultivation systems called plant factories. To investigate the effects of photosynthetic photon flux (PPF) on tomato fruit yield and the accumulation of recombinant miraculin, a taste-modifying glycoprotein, in transgenic tomato fruits, plants were cultivated at various PPFs from 100 to 400 (µmol m(-2) s(-)1) in a plant factory. Miraculin production per unit of energy used was highest at PPF100, although miraculin production per unit area was highest at PPF300. The commercial productivity of recombinant miraculin in transgenic tomato fruits largely depended on light conditions in the plant factory. Our trial will be useful to consider the trade-offs between the profits from production of high-value materials in plants and the costs of electricity.

Glutathionylation and Reduction of Methacrolein in Tomato Plants Account for Its Absorption from the Vapor Phase1[OPEN

PubMed Central

Muramoto, Shoko; Matsubara, Yayoi; Mwenda, Cynthia Mugo; Koeduka, Takao; Sakami, Takuya; Tani, Akira; Matsui, Kenji

2015-01-01

A large portion of the volatile organic compounds emitted by plants are oxygenated to yield reactive carbonyl species, which have a big impact on atmospheric chemistry. Deposition to vegetation driven by the absorption of reactive carbonyl species into plants plays a major role in cleansing the atmosphere, but the mechanisms supporting this absorption have been little examined. Here, we performed model experiments using methacrolein (MACR), one of the major reactive carbonyl species formed from isoprene, and tomato (Solanum lycopersicum) plants. Tomato shoots enclosed in a jar with MACR vapor efficiently absorbed MACR. The absorption efficiency was much higher than expected from the gas/liquid partition coefficient of MACR, indicating that MACR was likely metabolized in leaf tissues. Isobutyraldehyde, isobutyl alcohol, and methallyl alcohol (MAA) were detected in the headspace and inside tomato tissues treated with MACR vapor, suggesting that MACR was enzymatically reduced. Glutathione (GSH) conjugates of MACR (MACR-GSH) and MAA (MAA-GSH) were also detected. MACR-GSH was essentially formed through spontaneous conjugation between endogenous GSH and exogenous MACR, and reduction of MACR-GSH to MAA-GSH was likely catalyzed by an NADPH-dependent enzyme in tomato leaves. Glutathionylation was the metabolic pathway most responsible for the absorption of MACR, but when the amount of MACR exceeded the available GSH, MACR that accumulated reduced photosynthetic capacity. In an experiment simulating the natural environment using gas flow, MACR-GSH and MAA-GSH accumulation accounted for 30% to 40% of the MACR supplied. These results suggest that MACR metabolism, especially spontaneous glutathionylation, is an essential factor supporting MACR absorption from the atmosphere by tomato plants. PMID:26169680

A Tolerant Behavior in Salt-Sensitive Tomato Plants can be Mimicked by Chemical Stimuli

PubMed Central

Flors, Víctor; Paradís, Mercedes; García-Andrade, Javier; Cerezo, Miguel; González-Bosch, Carmen

2007-01-01

Lycopersicon esculentum plants exhibit increased salt stress tolerance following treatment with adipic acid monoethylester and 1,3-diaminepropane (DAAME), known as an inducer of resistance against biotic stress in tomato and pepper. For an efficient water and nutrient uptake, plants should adapt their water potential to compensate a decrease in water soil potential produced by salt stress. DAAME-treated plants showed a faster and stronger water potential reduction and an enhanced proline accumulation. Salinity-induced oxidative stress was also ameliorated by DAAME treatments. Oxidative membrane damage and ethylene emission were both reduced in DAAME-treated plants. This effect is probably a consequence of an increase of both non-enzymatic antioxidant activity as well as peroxidase activity. DAAME-mediated tolerance resulted in an unaltered photosynthetic rate and a stimulation of the decrease in transpiration under stress conditions without a cost in growth due to salt stress. The reduction in transpiration rate was concomitant with a reduction in phytotoxic Na+ and Cl− accumulation under saline stress. Interestingly, the ABA deficient tomato mutant sitiens was insensitive to DAAME-induced tolerance following NaCl stress exposure. Additionally, DAAME treatments increased the ABA content of leaves, therefore, an intact ABA signalling pathway seems to be important to express DAAME-induced salt tolerance. Here, we show a possibility of enhance tomato stress tolerance by chemical induction of the major plant defences against salt stress. DAAME-induced tolerance against salt stress could be complementary to or share elements with induced resistance against biotic stress. This might be the reason for the observed wide spectrum of effectiveness of this compound. PMID:19516968

Agrobacterium rhizogenes rolB gene affects photosynthesis and chlorophyll content in transgenic tomato (Solanum lycopersicum L.) plants.

PubMed

Bettini, Priscilla P; Marvasi, Massimiliano; Fani, Fabiola; Lazzara, Luigi; Cosi, Elena; Melani, Lorenzo; Mauro, Maria Luisa

2016-10-01

Insertion of Agrobacterium rhizogenes rolB gene into plant genome affects plant development, hormone balance and defence. However, beside the current research, the overall transcriptional response and gene expression of rolB as a modulator in plant is unknown. Transformed rolB tomato plant (Solanum lycopersicum L.) cultivar Tondino has been used to investigate the differential expression profile. Tomato is a well-known model organism both at the genetic and molecular level, and one of the most important commercial food crops in the world. Through the construction and characterization of a cDNA subtracted library, we have investigated the differential gene expression between transgenic clones of rolB and control tomato and have evaluated genes specifically transcribed in transgenic rolB plants. Among the selected genes, five genes encoding for chlorophyll a/b binding protein, carbonic anhydrase, cytochrome b 6 /f complex Fe-S subunit, potassium efflux antiporter 3, and chloroplast small heat-shock protein, all involved in chloroplast function, were identified. Measurement of photosynthesis efficiency by the level of three different photosynthetic parameters (F v /F m , rETR, NPQ) showed rolB significant increase in non-photochemical quenching and a, b chlorophyll content. Our results point to highlight the role of rolB on plant fitness by improving photosynthesis. Copyright © 2016 Elsevier GmbH. All rights reserved.

Priming by Rhizobacterium Protects Tomato Plants from Biotrophic and Necrotrophic Pathogen Infections through Multiple Defense Mechanisms

PubMed Central

Ahn, Il-Pyung; Lee, Sang-Woo; Kim, Min Gab; Park, Sang-Ryeol; Hwang, Duk-Ju; Bae, Shin-Chul

2011-01-01

A selected strain of rhizobacterium, Pseudomonas putida strain LSW17S (LSW17S), protects tomato plants (Lycopersicon esculentum L. cv. Seokwang) from bacterial speck by biotrophic Pseudomonas syringae pv. tomato strain DC3000 (DC3000) and bacterial wilt by necrotrophic Ralstonia solanacearum KACC 10703 (Rs10703). To investigate defense mechanisms induced by LSW17S in tomato plants, transcription patterns of pathogenesis-related (PR) genes and H2O2 production were analyzed in plants treated with LSW17S and subsequent pathogen inoculation. LSW17S alone did not induce transcriptions of employed PR genes in leaves and roots. DC3000 challenge following LSW17S triggered rapid transcriptions of PR genes and H2O2 production in leaves and roots. Catalase infiltration with DC3000 attenuated defense-related responses and resistance against DC3000 infection. Despite depriving H2O2 production and PR1b transcription by the same treatment, resistance against Rs10703 infection was not deterred significantly. H2O2 is indispensable for defense signaling and/or mechanisms primed by LSW17S and inhibition of bacterial speck, however, it is not involved in resistance against bacterial wilt. PMID:21710203

The tomato calcium sensor Cbl10 and its interacting protein kinase Cipk6 define a signaling pathway in plant immunity.

PubMed

de la Torre, Fernando; Gutiérrez-Beltrán, Emilio; Pareja-Jaime, Yolanda; Chakravarthy, Suma; Martin, Gregory B; del Pozo, Olga

2013-07-01

Ca(2+) signaling is an early and necessary event in plant immunity. The tomato (Solanum lycopersicum) kinase Pto triggers localized programmed cell death (PCD) upon recognition of Pseudomonas syringae effectors AvrPto or AvrPtoB. In a virus-induced gene silencing screen in Nicotiana benthamiana, we independently identified two components of a Ca(2+)-signaling system, Cbl10 (for calcineurin B-like protein) and Cipk6 (for calcineurin B-like interacting protein kinase), as their silencing inhibited Pto/AvrPto-elicited PCD. N. benthamiana Cbl10 and Cipk6 are also required for PCD triggered by other plant resistance genes and virus, oomycete, and nematode effectors and for host susceptibility to two P. syringae pathogens. Tomato Cipk6 interacts with Cbl10 and its in vitro kinase activity is enhanced in the presence of Cbl10 and Ca(2+), suggesting that tomato Cbl10 and Cipk6 constitute a Ca(2+)-regulated signaling module. Overexpression of tomato Cipk6 in N. benthamiana leaves causes accumulation of reactive oxygen species (ROS), which requires the respiratory burst homolog RbohB. Tomato Cbl10 and Cipk6 interact with RbohB at the plasma membrane. Finally, Cbl10 and Cipk6 contribute to ROS generated during effector-triggered immunity in the interaction of P. syringae pv tomato DC3000 and N. benthamiana. We identify a role for the Cbl/Cipk signaling module in PCD, establishing a mechanistic link between Ca(2+) and ROS signaling in plant immunity.

Polychromatic Supplemental Lighting from underneath Canopy Is More Effective to Enhance Tomato Plant Development by Improving Leaf Photosynthesis and Stomatal Regulation

PubMed Central

Song, Yu; Jiang, Chengyao; Gao, Lihong

2016-01-01

Light insufficient stress caused by canopy interception and mutual shading is a major factor limiting plant growth and development in intensive crop cultivation. Supplemental lighting can be used to give light to the lower canopy leaves and is considered to be an effective method to cope with low irradiation stress. Leaf photosynthesis, stomatal regulation, and plant growth and development of young tomato plants were examined to estimate the effects of supplemental lighting with various composite spectra and different light orientations. Light-emitting diodes (LEDs) of polychromatic light quality, red + blue (R/B), white + red + blue (W/R/B), white + red + far-red (W/R/FR), and white + blue (W/B) were assembled from the underneath canopy or from the inner canopy as supplemental lighting resources. The results showed that the use of supplemental lighting significantly increased the photosynthetic efficiency, and reduced stomatal closure while promoting plant growth. Among all supplemental lighting treatments, the W/R/B and W/B from the underneath canopy had best performance. The different photosynthetic performances among the supplemental lighting treatments are resulted from variations in CO2 utilization. The enhanced blue light fraction in the W/R/B and W/B could better stimulate stomatal opening and promote photosynthetic electron transport activity, thus better improving photosynthetic rate. Compared with the inner canopy treatment, the supplemental lighting from the underneath canopy could better enhance the carbon dioxide assimilation efficiency and excessive energy dissipation, leading to an improved photosynthetic performance. Stomatal morphology was highly correlated to leaf photosynthesis and plant development, and should thus be an important determinant for the photosynthesis and the growth of greenhouse tomatoes. PMID:28018376

Effect of essential oil of Origanum rotundifolium on some plant pathogenic bacteria, seed germination and plant growth of tomato

NASA Astrophysics Data System (ADS)

Dadaşoǧlu, Fatih; Kotan, Recep; Karagöz, Kenan; Dikbaş, Neslihan; Ćakmakçi, Ramazan; Ćakir, Ahmet; Kordali, Şaban; Özer, Hakan

2016-04-01

The aim of this study is to determine effect of Origanum rotundifolium's essential oil on some plant pathogenic bacterias, seed germination and plant growth of tomato. Xanthomonas axanopodis pv. vesicatoria strain (Xcv-761) and Clavibacter michiganensis ssp. michiganensis strain (Cmm) inoculated to tomato seed. The seeds were tested for germination in vitro and disease severity and some plant growth parameters in vivo. In vitro assay, maximum seed germination was observed at 62,5 µl/ml essential oil treatment in seeds inoculated with Xcv-761 and at 62,5 µl/ml essential oil and streptomycin treatment in seeds inoculated with Cmm. The least infected cotiledon number was observed at 500 µg/ml streptomycin treatment in seeds inoculated with Cmm. In vivo assay, maximum seed germination was observed at 250 µl/ml essential oil teratment in tomato inoculated with Cmm. Lowest disease severity, is seen in the CMM infected seeds with 250 µl/ml essential oil application these results were statistically significant when compared with pathogen infected seeds. Similarly, in application conducted with XCV-761 infected seed, the lowest disease severity was observed for seeds as a result of 250 µl/ml essential oil application. Also according to the results obtained from essential oil application of CMM infected seeds conducted with 62,5 µl/ml dose; while disease severity was found statistically insignificant compared to 250 µl/ml to essential oil application, ıt was found statistically significant compared to pathogen infected seeds. The results showed that essential oil of O. rotundifolium has a potential for some suppressed plant disease when it is used in appropriate dose.

Plant pathogen-induced water-soaking promotes Salmonella enterica growth on tomato leaves.

PubMed

Potnis, Neha; Colee, James; Jones, Jeffrey B; Barak, Jeri D

2015-12-01

Plant pathogen infection is a critical factor for the persistence of Salmonella enterica on plants. We investigated the mechanisms responsible for the persistence of S. enterica on diseased tomato plants by using four diverse bacterial spot Xanthomonas species that differ in disease severities. Xanthomonas euvesicatoria and X. gardneri infection fostered S. enterica growth, while X. perforans infection did not induce growth but supported the persistence of S. enterica. X. vesicatoria-infected leaves harbored S. enterica populations similar to those on healthy leaves. Growth of S. enterica was associated with extensive water-soaking and necrosis in X. euvesicatoria- and X. gardneri-infected plants. The contribution of water-soaking to the growth of S. enterica was corroborated by an increased growth of populations on water-saturated leaves in the absence of a plant pathogen. S. enterica aggregates were observed with bacterial spot lesions caused by either X. euvesicatoria or X. vesicatoria; however, more S. enterica aggregates formed on X. euvesicatoria-infected leaves as a result of larger lesion sizes per leaf area and extensive water-soaking. Sparsely distributed lesions caused by X. vesicatoria infection do not support the overall growth of S. enterica or aggregates in areas without lesions or water-soaking; S. enterica was observed as single cells and not aggregates. Thus, pathogen-induced water-soaking and necrosis allow S. enterica to replicate and proliferate on tomato leaves. The finding that the pathogen-induced virulence phenotype affects the fate of S. enterica populations in diseased plants suggests that targeting of plant pathogen disease is important in controlling S. enterica populations on plants. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Accumulation of free polyamines enhances the antioxidant response in fruits of grafted tomato plants under water stress.

PubMed

Sánchez-Rodríguez, E; Romero, L; Ruiz, J M

2016-01-15

Polyamines, small aliphatic polycations, have been suggested to play key roles in a number of biological processes. In this paper, attempts were made to investigate the possibility of improving antioxidant response of tomato fruits in relation with endogenous free polyamines content. We studied the reactive oxygen species and polyamines content, and antioxidant and polyamine-biosynthesis enzyme activities in fruits of ungrafted and grafted tomato plants under moderate water stress. We used a drought-tolerant cultivar (Zarina) and drought-sensitive cultivar (Josefina) to obtain reciprocal graft, selfgraft and ungraft plants. Fruits contained higher endogenous polyamine content during the course of the experiment relative to the control, coupled with higher arginine decarboxylase and spermine synthase activities in Zarina ungrafted and ZarxJos. In these cultivars, tomato fruits showed a lower reactive oxygen species generation and higher catalase and superoxide dismutase activities, suggesting that a higher content in polyamines (especially spermine) exerted a positive effect on antioxidant systems. All of these data suggest that spermine leads to more effective reactive oxygen species scavenging (less tissue damage) in tomato fruits, which may function collectively to enhance dehydration tolerance. Copyright © 2015 Elsevier GmbH. All rights reserved.

Snf2 family gene distribution in higher plant genomes reveals DRD1 expansion and diversification in the tomato genome.

PubMed

Bargsten, Joachim W; Folta, Adam; Mlynárová, Ludmila; Nap, Jan-Peter

2013-01-01

As part of large protein complexes, Snf2 family ATPases are responsible for energy supply during chromatin remodeling, but the precise mechanism of action of many of these proteins is largely unknown. They influence many processes in plants, such as the response to environmental stress. This analysis is the first comprehensive study of Snf2 family ATPases in plants. We here present a comparative analysis of 1159 candidate plant Snf2 genes in 33 complete and annotated plant genomes, including two green algae. The number of Snf2 ATPases shows considerable variation across plant genomes (17-63 genes). The DRD1, Rad5/16 and Snf2 subfamily members occur most often. Detailed analysis of the plant-specific DRD1 subfamily in related plant genomes shows the occurrence of a complex series of evolutionary events. Notably tomato carries unexpected gene expansions of DRD1 gene members. Most of these genes are expressed in tomato, although at low levels and with distinct tissue or organ specificity. In contrast, the Snf2 subfamily genes tend to be expressed constitutively in tomato. The results underpin and extend the Snf2 subfamily classification, which could help to determine the various functional roles of Snf2 ATPases and to target environmental stress tolerance and yield in future breeding.

Silencing C19-GA 2-oxidases induces parthenocarpic development and inhibits lateral branching in tomato plants

PubMed Central

Martínez-Bello, Liliam; Moritz, Thomas; López-Díaz, Isabel

2015-01-01

Gibberellins (GAs) are phytohormones that regulate a wide range of developmental processes in plants. Levels of active GAs are regulated by biosynthetic and catabolic enzymes like the GA 2-oxidases (GA2oxs). In tomato (Solanum lycopersicum L.) C19 GA2oxs are encoded by a small multigenic family of five members with some degree of redundancy. In order to investigate their roles in tomato, the silencing of all five genes in transgenic plants was induced. A significant increase in active GA4 content was found in the ovaries of transgenic plants. In addition, the transgenic unfertilized ovaries were much bigger than wild-type ovaries (about 30 times) and a certain proportion (5–37%) were able to develop parthenocarpically. Among the GA2ox family, genes GA2ox1 and -2 seem to be the most relevant for this phenotype since their expression was induced in unfertilized ovaries and repressed in developing fruits, inversely correlating with ovary growth. Interestingly, transgenic lines exhibited a significant inhibition of branching and a higher content of active GA4 in axillary buds. This phenotype was reverted, in transgenic plants, by the application of paclobutrazol, a GA biosynthesis inhibitor, suggesting a role for GAs as repressors of branching. In summary, this work demonstrates that GA 2-oxidases regulate gibberellin levels in ovaries and axillary buds of tomato plants and their silencing is responsible for parthenocarpic fruit growth and branching inhibition. PMID:26093022

Apical Correlative Effects in Leaf Epinasty of Tomato 1

PubMed Central

Kazemi, Saidollah; Kefford, Noel P.

1974-01-01

The influence of the stem apex on leaf curvature was investigated using debudded tomato (Lycopersicon esculentum Mill. cv Anahu) plants and petiole explants, consisting of a section of petiole attached to a section of stem. Decapitation of the main shoot of tomato plants induced hyponasty of petioles in young leaves. Application of auxin in place of the removed apex or fumigation of intact tomato plants with ethylene produced epinastic curvature at the base of the petiole. Simultaneous carbon dioxide treatments prevented the development of petiolar epinasty due to auxin and ethylene treatments. Application of ethylene gas to the decapitated shoot or injection into the stem, induced petiolar epinasty. In a saturating level of ethylene gas, tomato petioles did not respond to indole-3-acetic acid applied to the cut apex. Auxin-induced ethylene production in petiole explants preceded the development of epinasty. Application of indoleacetic acid in lanolin to the entire lower side of the petioles of leaves in situ produced petiole epinasty. Petiolar epinasty due to apically applied indoleacetic acid resulted from differential cell elongation. The auxins indole-3-acetic acid, 2,4-dichlorophenoxyacetic acid, and naphthalene-1-acetic acid induced epinasty when applied apically to decapitated tomato plants, while gibberellic acid, kinetin, abscisic acid, and auxin or gibberellin antagonists had no effect. When such compounds were applied to petiole explants, only indole-3-acetic acid and kinetin caused an increase in ethylene production and the effect of kinetin was relatively weak. Application of 2,3,5-triiodobenzoic acid around the stem did not change the effect on petiolar epinasty of auxin applied to the decapitated shoot or around the stem. Radioautography showed that the label from 14C-indoleacetic acid applied apically entered the petiole and midrib tissue; however, extraction showed that only a fraction of the label in these tissues was in the form of indoleacetic

Using hyperspectral imaging technology to identify diseased tomato leaves

NASA Astrophysics Data System (ADS)

Li, Cuiling; Wang, Xiu; Zhao, Xueguan; Meng, Zhijun; Zou, Wei

2016-11-01

In the process of tomato plants growth, due to the effect of plants genetic factors, poor environment factors, or disoperation of parasites, there will generate a series of unusual symptoms on tomato plants from physiology, organization structure and external form, as a result, they cannot grow normally, and further to influence the tomato yield and economic benefits. Hyperspectral image usually has high spectral resolution, not only contains spectral information, but also contains the image information, so this study adopted hyperspectral imaging technology to identify diseased tomato leaves, and developed a simple hyperspectral imaging system, including a halogen lamp light source unit, a hyperspectral image acquisition unit and a data processing unit. Spectrometer detection wavelength ranged from 400nm to 1000nm. After hyperspectral images of tomato leaves being captured, it was needed to calibrate hyperspectral images. This research used spectrum angle matching method and spectral red edge parameters discriminant method respectively to identify diseased tomato leaves. Using spectral red edge parameters discriminant method produced higher recognition accuracy, the accuracy was higher than 90%. Research results have shown that using hyperspectral imaging technology to identify diseased tomato leaves is feasible, and provides the discriminant basis for subsequent disease control of tomato plants.

Spectrophotometric analysis of tomato plants produced from seeds exposed under space flight conditions for a long time

NASA Astrophysics Data System (ADS)

Nechitailo, Galina S.; Yurov, S.; Cojocaru, A.; Revin, A.

The analysis of the lycopene and other carotenoids in tomatoes produced from seeds exposed under space flight conditions at the orbital station MIR for six years is presented in this work. Our previous experiments with tomato plants showed the germination of seeds to be 32%Genetic investigations revealed 18%in the experiment and 8%experiments were conducted to study the capacity of various stimulating factors to increase germination of seeds exposed for a long time to the action of space flight factors. An increase of 20%achieved but at the same time mutants having no analogues in the control variants were detected. For the present investigations of the third generation of plants produced from seeds stored for a long time under space flight conditions 80 tomatoes from forty plants were selected. The concentration of lycopene in the experimental specimens was 2.5-3 times higher than in the control variants. The spectrophotometric analysis of ripe tomatoes revealed typical three-peaked carotenoid spectra with a high maximum of lycopene (a medium maximum at 474 nm), a moderate maximum of its predecessor, phytoin, (a medium maximum at 267 nm) and a low maximum of carotenes. In green tomatoes, on the contrary, a high maximum of phytoin, a moderate maximum of lycopene and a low maximum of carotenes were observed. The results of the spectral analysis point to the retardation of biosynthesis of carotenes while the production of lycopene is increased and to the synthesis of lycopene from phytoin. Electric conduction of tomato juice in the experimental samples is increased thus suggesting higher amounts of carotenoids, including lycopene and electrolytes. The higher is the value of electric conduction of a specimen, the higher are the spectral maxima of lycopene. The hydrogen ion exponent of the juice of ripe tomatoes increases due to which the efficiency of ATP biosynthesis in cell mitochondria is likely to increase, too. The results demonstrating an increase in the content

The vascular plant-pathogenic bacterium Ralstonia solanacearum produces biofilms required for its virulence on the surfaces of tomato cells adjacent to intercellular spaces.

PubMed

Mori, Yuka; Inoue, Kanako; Ikeda, Kenichi; Nakayashiki, Hitoshi; Higashimoto, Chikaki; Ohnishi, Kouhei; Kiba, Akinori; Hikichi, Yasufumi

2016-08-01

The mechanism of colonization of intercellular spaces by the soil-borne and vascular plant-pathogenic bacterium Ralstonia solanacearum strain OE1-1 after invasion into host plants remains unclear. To analyse the behaviour of OE1-1 cells in intercellular spaces, tomato leaves with the lower epidermis layers excised after infiltration with OE1-1 were observed under a scanning electron microscope. OE1-1 cells formed microcolonies on the surfaces of tomato cells adjacent to intercellular spaces, and then aggregated surrounded by an extracellular matrix, forming mature biofilm structures. Furthermore, OE1-1 cells produced mushroom-type biofilms when incubated in fluids of apoplasts including intercellular spaces, but not xylem fluids from tomato plants. This is the first report of biofilm formation by R. solanacearum on host plant cells after invasion into intercellular spaces and mushroom-type biofilms produced by R. solanacearum in vitro. Sugar application led to enhanced biofilm formation by OE1-1. Mutation of lecM encoding a lectin, RS-IIL, which reportedly exhibits affinity for these sugars, led to a significant decrease in biofilm formation. Colonization in intercellular spaces was significantly decreased in the lecM mutant, leading to a loss of virulence on tomato plants. Complementation of the lecM mutant with native lecM resulted in the recovery of mushroom-type biofilms and virulence on tomato plants. Together, our findings indicate that OE1-1 produces mature biofilms on the surfaces of tomato cells after invasion into intercellular spaces. RS-IIL may contribute to biofilm formation by OE1-1, which is required for OE1-1 virulence. © 2015 BSPP AND JOHN WILEY & SONS LTD.

NH4 + protects tomato plants against Pseudomonas syringae by activation of systemic acquired acclimation

PubMed Central

Fernández-Crespo, Emma; Scalschi, Loredana; Llorens, Eugenio; García-Agustín, Pilar; Camañes, Gemma

2015-01-01

NH4 + nutrition provokes mild toxicity by enhancing H2O2 accumulation, which acts as a signal activating systemic acquired acclimation (SAA). Until now, induced resistance mechanisms in response to an abiotic stimulus and related to SAA were only reported for exposure to a subsequent abiotic stress. Herein, the first evidence is provided that this acclimation to an abiotic stimulus induces resistance to later pathogen infection, since NH4 + nutrition (N-NH4 +)-induced resistance (NH4 +-IR) against Pseudomonas syringae pv tomato DC3000 (Pst) in tomato plants was demonstrated. N-NH4 + plants displayed basal H2O2, abscisic acid (ABA), and putrescine (Put) accumulation. H2O2 accumulation acted as a signal to induce ABA-dependent signalling pathways required to prevent NH4 + toxicity. This acclimatory event provoked an increase in resistance against later pathogen infection. N-NH4 + plants displayed basal stomatal closure produced by H2O2 derived from enhanced CuAO and rboh1 activity that may reduce the entry of bacteria into the mesophyll, diminishing the disease symptoms as well as strongly inducing the oxidative burst upon Pst infection, favouring NH4 +-IR. Experiments with inhibitors of Put accumulation and the ABA-deficient mutant flacca demonstrated that Put and ABA downstream signalling pathways are required to complete NH4 +-IR. The metabolic profile revealed that infected N-NH4 + plants showed greater ferulic acid accumulation compared with control plants. Although classical salicylic acid (SA)-dependent responses against biotrophic pathogens were not found, the important role of Put in the resistance of tomato against Pst was demonstrated. Moreover, this work revealed the cross-talk between abiotic stress acclimation (NH4 + nutrition) and resistance to subsequent Pst infection. PMID:26246613

NH4+ protects tomato plants against Pseudomonas syringae by activation of systemic acquired acclimation.

PubMed

Fernández-Crespo, Emma; Scalschi, Loredana; Llorens, Eugenio; García-Agustín, Pilar; Camañes, Gemma

2015-11-01

NH4 (+) nutrition provokes mild toxicity by enhancing H2O2 accumulation, which acts as a signal activating systemic acquired acclimation (SAA). Until now, induced resistance mechanisms in response to an abiotic stimulus and related to SAA were only reported for exposure to a subsequent abiotic stress. Herein, the first evidence is provided that this acclimation to an abiotic stimulus induces resistance to later pathogen infection, since NH4 (+) nutrition (N-NH4 (+))-induced resistance (NH4 (+)-IR) against Pseudomonas syringae pv tomato DC3000 (Pst) in tomato plants was demonstrated. N-NH4 (+) plants displayed basal H2O2, abscisic acid (ABA), and putrescine (Put) accumulation. H2O2 accumulation acted as a signal to induce ABA-dependent signalling pathways required to prevent NH4 (+) toxicity. This acclimatory event provoked an increase in resistance against later pathogen infection. N-NH4 (+) plants displayed basal stomatal closure produced by H2O2 derived from enhanced CuAO and rboh1 activity that may reduce the entry of bacteria into the mesophyll, diminishing the disease symptoms as well as strongly inducing the oxidative burst upon Pst infection, favouring NH4 (+)-IR. Experiments with inhibitors of Put accumulation and the ABA-deficient mutant flacca demonstrated that Put and ABA downstream signalling pathways are required to complete NH4 (+)-IR. The metabolic profile revealed that infected N-NH4 (+) plants showed greater ferulic acid accumulation compared with control plants. Although classical salicylic acid (SA)-dependent responses against biotrophic pathogens were not found, the important role of Put in the resistance of tomato against Pst was demonstrated. Moreover, this work revealed the cross-talk between abiotic stress acclimation (NH4 (+) nutrition) and resistance to subsequent Pst infection. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology.

Bioassimilable sulphur provides effective control of Oidium neolycopersici in tomato, enhancing the plant immune system.

PubMed

Llorens, Eugenio; Agustí-Brisach, Carlos; González-Hernández, Ana I; Troncho, Pilar; Vicedo, Begonya; Yuste, Teresa; Orero, Mayte; Ledó, Carlos; García-Agustín, Pilar; Lapeña, Leonor

2017-05-01

Developments of alternatives to the use of chemical pesticides to control pests are focused on the induction of natural plant defences. The study of new compounds based on liquid bioassimilable sulphur and its effect as an inductor of the immune system of plants would provide an alternative option to farmers to enhance plant resistance against pathogen attacks such as powdery mildew. In order to elucidate the efficacy of this compound in tomato against powdery mildew, we tested several treatments: curative foliar, preventive foliar, preventive in soil drench and combining preventive in soil drench and curative foliar. In all cases, treated plants showed lower infection development, better physiological parameters and a higher level of chlorophyll. We also observed better performance in parameters involved in plant resistance such as antioxidant response, callose deposition and hormonal levels. The results indicate that preventive and curative treatments can be highly effective for the prevention and control of powdery mildew in tomato plants. Foliar treatments are able to stop the pathogen development when they are applied as curative. Soil drench treatments induce immune response mechanisms of plants, increasing significantly callose deposition and promoting plant development. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Embryogenesis induction, callogenesis, and plant regeneration by in vitro culture of tomato isolated microspores and whole anthers.

PubMed

Seguí-Simarro, José M; Nuez, Fernando

2007-01-01

In this work, some of the different in vitro developmental pathways into which tomato microspores or microsporocytes can be deviated experimentally were explored. The two principal ones are direct embryogenesis from isolated microspores and callus formation from meiocyte-containing anthers. By means of light and electron microscopy, the process of early embryogenesis from isolated microspores and the disruption of normal meiotic development and change of developmental fate towards callus proliferation, morphogenesis, and plant regeneration have been shown. From microspores isolated at the vacuolate stage, embryos can be directly induced, thus avoiding non-androgenic products. In contrast, several different morphogenic events can be triggered in cultures of microsporocyte-containing anthers under adequate conditions, including indirect embryogenesis, adventitious organogenesis, and plant regeneration. Both callus and regenerated plants may be haploid, diploid, and mostly mixoploid. The results demonstrate that both gametophytic and sporophytic calli occur in cultured tomato anthers, and point to an in vitro-induced disturbance of cytokinesis and subsequent fusion of daughter nuclei as a putative cause for mixoploidy and genome doubling during both tetrad compartmentalization and callus proliferation. The potential implications of the different alternative pathways are discussed in the context of their application to the production of doubled-haploid plants in tomato, which is still very poorly developed.

Bacterial siderophores efficiently provide iron to iron-starved tomato plants in hydroponics culture.

PubMed

Radzki, W; Gutierrez Mañero, F J; Algar, E; Lucas García, J A; García-Villaraco, A; Ramos Solano, B

2013-09-01

Iron is one of the essential elements for a proper plant development. Providing plants with an accessible form of iron is crucial when it is scant or unavailable in soils. Chemical chelates are the only current alternative and are highly stable in soils, therefore, posing a threat to drinking water. The aim of this investigation was to quantify siderophores produced by two bacterial strains and to determine if these bacterial siderophores would palliate chlorotic symptoms of iron-starved tomato plants. For this purpose, siderophore production in MM9 medium by two selected bacterial strains was quantified, and the best was used for biological assay. Bacterial culture media free of bacteria (S) and with bacterial cells (BS), both supplemented with Fe were delivered to 12-week-old plants grown under iron starvation in hydroponic conditions; controls with full Hoagland solution, iron-free Hoagland solution and water were also conducted. Treatments were applied twice along the experiment, with a week in between. At harvest, plant yield, chlorophyll content and nutritional status in leaves were measured. Both the bacterial siderophore treatments significantly increased plant yield, chlorophyll and iron content over the positive controls with full Hoagland solution, indicating that siderophores are effective in providing Fe to the plant, either with or without the presence of bacteria. In summary, siderophores from strain Chryseobacterium C138 are effective in supplying Fe to iron-starved tomato plants by the roots, either with or without the presence of bacteria. Based on the amount of siderophores produced, an effective and economically feasible organic Fe chelator could be developed.

Field performance of cucurbit and tomato plants infected with a nonpathogenic mutant of Colletotrichum magna (teleomorph: Glomerella magna; Jekins and Winstead)

USGS Publications Warehouse

Redman, R.S.; Roossinck, M.J.; Maher, S.; Rodriguez, R.J.

2002-01-01

Path-1 is a UV-induced non-pathogenic mutant of a virulent Colletotrichum magna isolate that establishes mutualistic symbioses with cucurbit and tomato species. Under laboratory conditions, this mutualism results in plant growth enhancement, drought tolerance, and disease protection against fungal pathogens. This study focuses on the efficacy of this symbiosis and the symbiotic lifestyle expressed by path-1 under field conditions in the absence of disease stress. The effects of colonization by path-1 on fruit yields and growth was measured in field plots with four cucurbit species including four watermelon cultivars, and two tomato cultivars, over four growing seasons. The persistence of the symbiosis, extent of colonization, and path-1 transmission were also assessed. Yields from path-1 infected plants were equivalent to or greater than yields from non-inoculated control plants and path-1 systemically colonized plants throughout each growing season. Path-1 also increased the growth rates of tomato plants and was not transmitted to uncolonized plants. The results indicate that there are no metabolic costs of this symbiosis and the symbiosis is maintained under field conditions.

Influence of simulated acidic rain on bacterial speck of tomato. [Lycopersicon esculentum Mill var. 'Chico III', Pseudomonas tomato

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bisessar, S.; Palmer, K.T.; Kuja, A.L.

Ambient rain in southern Ontario has a volume-weighted average pH of approximately 4.2. Tomato (Lycopersicon esculentum Mill var. 'Chico III') seedlings were exposed to simulated acidic rain in specially designed chambers. The inoculum of Pseudomonas tomato (Okabe) Alstatt, causal agent of bacterial speck, was sprayed on plants before or after exposure to acidic rain of pH 2.5, 3.5, and 4.5, as well as on plants not exposed to the simulated acidic rain. Speck symptoms (small, dark, brown spots with yellow halos) were found on all inoculated plants. Exposure of plants to simulted acidic rain inhibited speck development, but the inhibitionmore » was greater on plants exposed to acidic rain after inoculation. Spot necrosis, a typical response to acid rain, occurred on up to 15 to 20% of the leaf area on all tomato plants treated with acidic rain at pH 2.5. Plants alos showed a decrease in growth (height and fresh and dry weights) with an increase in rain acidity. Leaves injured by simulated acidic rain and examined histopathologically displayed cellular malformations including hyperplasia and hypertrophy. Pseudomonas tomato failed to grow on acidified King B medium or Difco nutrient broth adjusted to pH 3.5 or lower.« less

Tomato chocolate spot virus, a member of a new torradovirus species that causes a necrosis-associated disease of tomato in Guatemala.

PubMed

Batuman, O; Kuo, Y-W; Palmieri, M; Rojas, M R; Gilbertson, R L

2010-06-01

Tomatoes in Guatemala have been affected by a new disease, locally known as "mancha de chocolate" (chocolate spot). The disease is characterized by distinct necrotic spots on leaves, stems and petioles that eventually expand and cause a dieback of apical tissues. Samples from symptomatic plants tested negative for infection by tomato spotted wilt virus, tobacco streak virus, tobacco etch virus and other known tomato-infecting viruses. A virus-like agent was sap-transmitted from diseased tissue to Nicotiana benthamiana and, when graft-transmitted to tomato, this agent induced chocolate spot symptoms. This virus-like agent also was sap-transmitted to Datura stramonium and Nicotiana glutinosa, but not to a range of non-solanaceous indicator plants. Icosahedral virions approximately 28-30 nm in diameter were purified from symptomatic N. benthamiana plants. When rub-inoculated onto leaves of N. benthamiana plants, these virions induced symptoms indistinguishable from those in N. benthamiana plants infected with the sap-transmissible virus associated with chocolate spot disease. Tomatoes inoculated with sap or grafted with shoots from N. benthamiana plants infected with purified virions developed typical chocolate spot symptoms, consistent with this virus being the causal agent of the disease. Analysis of nucleic acids associated with purified virions of the chocolate-spot-associated virus, revealed a genome composed of two single-stranded RNAs of approximately 7.5 and approximately 5.1 kb. Sequence analysis of these RNAs revealed a genome organization similar to recently described torradoviruses, a new group of picorna-like viruses causing necrosis-associated diseases of tomatoes in Europe [tomato torrado virus (ToTV)] and Mexico [tomato apex necrosis virus (ToANV) and tomato marchitez virus (ToMarV)]. Thus, the approximately 7.5 kb and approximately 5.1 kb RNAs of the chocolate-spot-associated virus corresponded to the torradovirus RNA1 and RNA2, respectively; however

Recessive Resistance Derived from Tomato cv. Tyking-Limits Drastically the Spread of Tomato Yellow Leaf Curl Virus

PubMed Central

Pereira-Carvalho, Rita C.; Díaz-Pendón, Juan A.; Fonseca, Maria Esther N.; Boiteux, Leonardo S.; Fernández-Muñoz, Rafael; Moriones, Enrique; Resende, Renato O.

2015-01-01

The tomato yellow leaf curl disease (TYLCD) causes severe damage to tomato (Solanum lycopersicum L.) crops throughout tropical and subtropical regions of the world. TYLCD is associated with a complex of single-stranded circular DNA plant viruses of the genus Begomovirus (family Geminiviridae) transmitted by the whitefy Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae). The tomato inbred line TX 468-RG is a source of monogenic recessive resistance to begomoviruses derived from the hybrid cv. Tyking F1. A detailed analysis of this germplasm source against tomato yellow leaf curl virus-Israel (TYLCV-IL), a widespread TYLCD-associated virus, showed a significant restriction to systemic virus accumulation even under continuous virus supply. The resistance was effective in limiting the onset of TYLCV-IL in tomato, as significantly lower primary spread of the virus occurred in resistant plants. Also, even if a limited number of resistant plants could result infected, they were less efficient virus sources for secondary spread owing to the impaired TYLCV-IL accumulation. Therefore, the incorporation of this resistance into breeding programs might help TYLCD management by drastically limiting TYLCV-IL spread. PMID:26008699

Tomato yellow leaf curl virus infection mitigates the heat stress response of plants grown at high temperatures

PubMed Central

Ghandi, Anfoka; Adi, Moshe; Lilia, Fridman; Linoy, Amrani; Or, Rotem; Mikhail, Kolot; Mouhammad, Zeidan; Henryk, Czosnek; Rena, Gorovits

2016-01-01

Cultured tomatoes are often exposed to a combination of extreme heat and infection with Tomato yellow leaf curl virus (TYLCV). This stress combination leads to intense disease symptoms and yield losses. The response of TYLCV-susceptible and resistant tomatoes to heat stress together with viral infection was compared. The plant heat-stress response was undermined in TYLCV infected plants. The decline correlated with the down-regulation of heat shock transcription factors (HSFs) HSFA2 and HSFB1, and consequently, of HSF-regulated genes Hsp17, Apx1, Apx2 and Hsp90. We proposed that the weakened heat stress response was due to the decreased capacity of HSFA2 to translocate into the nuclei of infected cells. All the six TYLCV proteins were able to interact with tomato HSFA2 in vitro, moreover, coat protein developed complexes with HSFA2 in nuclei. Capturing of HSFA2 by viral proteins could suppress the transcriptional activation of heat stress response genes. Application of both heat and TYLCV stresses was accompanied by the development of intracellular large protein aggregates containing TYLCV proteins and DNA. The maintenance of cellular chaperones in the aggregated state, even after recovery from heat stress, prevents the circulation of free soluble chaperones, causing an additional decrease in stress response efficiency. PMID:26792235

Tomato linalool synthase is induced in trichomes by jasmonic acid

PubMed Central

van Schie, Chris C. N.; Haring, Michel A.

2007-01-01

Tomato (Lycopersicon esculentum) plants emit a blend of volatile organic compounds, which mainly consists of terpenes. Upon herbivory or wounding, the emission of several terpenes increases. We have identified and characterized the first two tomato monoterpene synthases, LeMTS1 and LeMTS2. Although these proteins were highly homologous, recombinant LeMTS1 protein produced (R)-linalool from geranyl diphosphate (GPP) and (E)-nerolidol from farnesyl diphosphate (FPP), while recombinant LeMTS2 produced β-phellandrene, β-myrcene, and sabinene from GPP. In addition, these genes were expressed in different tissues: LeMTS1 was expressed in flowers, young leaves, stems, and petioles, while LeMTS2 was strongest expressed in stems and roots. LeMTS1 expression in leaves was induced by spider mite-infestation, wounding and jasmonic acid (JA)-treatment, while LeMTS2 did not respond to these stimuli. The expression of LeMTS1 in stems and petioles was predominantly detected in trichomes and could be induced by JA. Because JA treatment strongly induced emission of linalool and overexpression of LeMTS1 in tomato resulted in increased production of linalool, we propose that LeMTS1 is a genuine linalool synthase. Our results underline the importance of trichomes in JA-induced terpene emission in tomato. PMID:17440821

Silencing of the tomato phosphatidylinositol-phospholipase C2 (SlPLC2) reduces plant susceptibility to Botrytis cinerea.

PubMed

Gonorazky, Gabriela; Guzzo, María Carla; Abd-El-Haliem, Ahmed M; Joosten, Matthieu H A J; Laxalt, Ana María

2016-12-01

The tomato [Solanum lycopersicum (Sl)] phosphatidylinositol-phospholipase C (PI-PLC) gene family is composed of six members, named SlPLC1 to SlPLC6, differentially regulated on pathogen attack. We have previously shown that the fungal elicitor xylanase induces a raise of SlPLC2 and SlPLC5 transcripts and that SlPLC2, but not SlPLC5, is required for xylanase-induced expression of defense-related genes. In this work we studied the role of SlPLC2 in the interaction between tomato and the necrotrophic fungus Botrytis cinerea. Inoculation of tomato leaves with B. cinerea increases SlPLC2 transcript levels. We knocked-down the expression of SlPLC2 by virus-induced gene silencing and plant defense responses were analyzed upon B. cinerea inoculation. SlPLC2 silenced plants developed smaller necrotic lesions concomitantly with less proliferation of the fungus. Silencing of SlPLC2 resulted as well in a reduced production of reactive oxygen species. Upon B. cinerea inoculation, transcript levels of the salicylic acid (SA)-defense pathway marker gene SlPR1a were diminished in SlPLC2 silenced plants compared to non-silenced infected plants, while transcripts of the jasmonic acid (JA)-defense gene markers Proteinase Inhibitor I and II (SlPI-I and SlPI-II) were increased. This implies that SlPLC2 participates in plant susceptibility to B. cinerea. © 2016 BSPP and John Wiley & Sons Ltd.

The role of corchorus in spreading of tomato yellow leaf curl virus on tomato in Jeddah, Saudi Arabia.

PubMed

Sohrab, Sayed Sartaj

2016-03-01

Corchorus (Corchorus capsularis L. and Corchorus olitorius L.) is one of the most important fiber crops grown in tropical and subtropical regions throughout the world. Field survey was conducted and naturally infected leaf samples were collected from corchorus and tomato plants in Jeddah, Saudi Arabia. The causal virus was transmitted by whiteflies to tomato plants and begomovirus infection was confirmed by Polymerase chain reaction. The complete viral genome and associated betasatellites were amplified, cloned and sequenced from both corchorus and tomato samples. The genetic variability and phylogenetic relationships were determined for both isolates (corchorus and tomato). The complete genome sequences showed highest (99.5 % nt) similarity with tomato yellow leaf curl virus (TYLCV) and formed closest cluster with TYLCV-Tomato reported from Jizan and Al-Qasim, Saudi Arabia and betasatellites sequences showed highest similarity (99.8 % nt) with Tomato yellow leaf curl betasatellites-Jeddah followed by Tomato yellow leaf curl Oman betasatellites and formed closed cluster with TYLCV-Tomato. On the basis of results obtained from whiteflies transmission, sequence similarity and phylogenetic relationships; it is concluded that the identified virus could be a variant of TYLCV circulating in the Kingdom. The significance of this study demonstrated that the corchorus is serving as reservoir and alternative host and playing an important role in spreading the begomovirus associated disease in the Kingdom of Saudi Arabia.

Refuse derived soluble bio-organics enhancing tomato plant growth and productivity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sortino, Orazio; Dipasquale, Mauro; Montoneri, Enzo, E-mail: enzo.montoneri@unito.it

2012-10-15

Highlights: Black-Right-Pointing-Pointer Municipal bio-wastes are a sustainable source of bio-based products. Black-Right-Pointing-Pointer Refuse derived soluble bio-organics promote chlorophyll synthesis. Black-Right-Pointing-Pointer Refuse derived soluble bio-organics enhance plant growth and fruit ripening rate. Black-Right-Pointing-Pointer Sustainable chemistry exploiting urban refuse allows sustainable development. Black-Right-Pointing-Pointer Chemistry, agriculture and the environment benefit from biowaste technology. - Abstract: Municipal bio-refuse (CVD), containing kitchen wastes, home gardening residues and public park trimmings, was treated with alkali to yield a soluble bio-organic fraction (SBO) and an insoluble residue. These materials were characterized using elemental analysis, potentiometric titration, and 13C NMR spectroscopy, and then applied as organic fertilizers tomore » soil for tomato greenhouse cultivation. Their performance was compared with a commercial product obtained from animal residues. Plant growth, fruit yield and quality, and soil and leaf chemical composition were the selected performance indicators. The SBO exhibited the best performance by enhancing leaf chlorophyll content, improving plant growth and fruit ripening rate and yield. No product performance-chemical composition relationship could be assessed. Solubility could be one reason for the superior performance of SBO as a tomato growth promoter. The enhancement of leaf chlorophyll content is discussed to identify a possible link with the SBO photosensitizing properties that have been demonstrated in other work, and thus with photosynthetic performance.« less

Synergistic effects of plant defense elicitors and Trichoderma harzianum on enhanced induction of antioxidant defense system in tomato against Fusarium wilt disease.

PubMed

Zehra, Andleeb; Meena, Mukesh; Dubey, Manish Kumar; Aamir, Mohd; Upadhyay, R S

2017-11-02

Plant defense against their pathogens can be induced by a complex network of different inducers. The present study investigates the synergistic effect of Trichoderma harzianum, exogenous salicylic acid (SA) and methyl jasmonate (MeJA) over the response and regulation of the antioxidant defense mechanisms and lipid peroxidation in tomato plants against Fusarium wilt disease. In the present work, tomato plants were infected by Fusarium oxysporum f. sp. lycopersici 3 days after inoculated with T. harzianum and/or sprayed daily for 3 days with chemical inducers (SA and MeJA). Plants were analysed at 0, 24, 48, 72 and 96 h after inoculation with Fusarium oxysporum f. sp. lycopersici. Infection of tomato plants by pathogen led to strong reduction in the dry weight of roots and shoots with the enhanced concentration of H 2 O 2 and varying degree of lipid peroxidation. Concurrently, exogenous SA, when applied with pathogen greatly enhanced H 2 O 2 content as well as activities of antioxidant enzymes except catalase (CAT) and ascorbate peroxidase (APx). The pathogen challenged plants pretreated with T. harzianum and MeJA together exhibited less lipid peroxidation and as well as the elevated level of ascorbic acid and enhanced activities of antioxidant enzymes. All applied treatments protected tomato seedlings against Fusarium wilt disease but the percentage of protection was found higher in plants pretreated with the combination of T. harzianum and chemical inducers.

Tomato Infection by Whitefly-Transmitted Circulative and Non-Circulative Viruses Induce Contrasting Changes in Plant Volatiles and Vector Behaviour

PubMed Central

Fereres, Alberto; Peñaflor, Maria Fernanda G. V.; Favaro, Carla F.; Azevedo, Kamila E. X.; Landi, Carolina H.; Maluta, Nathalie K. P.; Bento, José Mauricio S.; Lopes, Joao R.S.

2016-01-01

Virus infection frequently modifies plant phenotypes, leading to changes in behaviour and performance of their insect vectors in a way that transmission is enhanced, although this may not always be the case. Here, we investigated Bemisia tabaci response to tomato plants infected by Tomato chlorosis virus (ToCV), a non-circulative-transmitted crinivirus, and Tomato severe rugose virus (ToSRV), a circulative-transmitted begomovirus. Moreover, we examined the role of visual and olfactory cues in host plant selection by both viruliferous and non-viruliferous B. tabaci. Visual cues alone were assessed as targets for whitefly landing by placing leaves underneath a Plexiglas plate. A dual-choice arena was used to assess whitefly response to virus-infected and mock-inoculated tomato leaves under light and dark conditions. Thereafter, we tested the whitefly response to volatiles using an active air-flow Y-tube olfactometer, and chemically characterized the blends using gas chromatography coupled to mass spectrometry. Visual stimuli tests showed that whiteflies, irrespective of their infectious status, always preferred to land on virus-infected rather than on mock-inoculated leaves. Furthermore, whiteflies had no preference for either virus-infected or mock-inoculated leaves under dark conditions, but preferred virus-infected leaves in the presence of light. ToSRV-infection promoted a sharp decline in the concentration of some tomato volatiles, while an increase in the emission of some terpenes after ToCV infection was found. ToSRV-viruliferous whiteflies preferred volatiles emitted from mock-inoculated plants, a conducive behaviour to enhance virus spread, while volatiles from ToCV-infected plants were avoided by non-viruliferous whiteflies, a behaviour that is likely detrimental to the secondary spread of the virus. In conclusion, the circulative persistent begomovirus, ToSRV, seems to have evolved together with its vector B. tabaci to optimise its own spread. However

Tomato Infection by Whitefly-Transmitted Circulative and Non-Circulative Viruses Induce Contrasting Changes in Plant Volatiles and Vector Behaviour.

PubMed

Fereres, Alberto; Peñaflor, Maria Fernanda G V; Favaro, Carla F; Azevedo, Kamila E X; Landi, Carolina H; Maluta, Nathalie K P; Bento, José Mauricio S; Lopes, Joao R S

2016-08-11

Virus infection frequently modifies plant phenotypes, leading to changes in behaviour and performance of their insect vectors in a way that transmission is enhanced, although this may not always be the case. Here, we investigated Bemisia tabaci response to tomato plants infected by Tomato chlorosis virus (ToCV), a non-circulative-transmitted crinivirus, and Tomato severe rugose virus (ToSRV), a circulative-transmitted begomovirus. Moreover, we examined the role of visual and olfactory cues in host plant selection by both viruliferous and non-viruliferous B. tabaci. Visual cues alone were assessed as targets for whitefly landing by placing leaves underneath a Plexiglas plate. A dual-choice arena was used to assess whitefly response to virus-infected and mock-inoculated tomato leaves under light and dark conditions. Thereafter, we tested the whitefly response to volatiles using an active air-flow Y-tube olfactometer, and chemically characterized the blends using gas chromatography coupled to mass spectrometry. Visual stimuli tests showed that whiteflies, irrespective of their infectious status, always preferred to land on virus-infected rather than on mock-inoculated leaves. Furthermore, whiteflies had no preference for either virus-infected or mock-inoculated leaves under dark conditions, but preferred virus-infected leaves in the presence of light. ToSRV-infection promoted a sharp decline in the concentration of some tomato volatiles, while an increase in the emission of some terpenes after ToCV infection was found. ToSRV-viruliferous whiteflies preferred volatiles emitted from mock-inoculated plants, a conducive behaviour to enhance virus spread, while volatiles from ToCV-infected plants were avoided by non-viruliferous whiteflies, a behaviour that is likely detrimental to the secondary spread of the virus. In conclusion, the circulative persistent begomovirus, ToSRV, seems to have evolved together with its vector B. tabaci to optimise its own spread. However

Salmonella transfer during pilot plant scale washing and roller conveying of tomatoes.

PubMed

Wang, Haiqiang; Ryser, Elliot T

2014-03-01

Salmonella transfer during washing and roller conveying of inoculated tomatoes was quantified using a pilot scale tomato packing line equipped with plastic, foam, or brush rollers. Red round tomatoes (2.3 kg) were dip inoculated with Salmonella enterica serovar Typhimurium LT2 (avirulent) (4 log CFU/g), air dried for 2 h, and then washed in sanitizer-free water for 2 min. Inoculated tomatoes were then passed single file over a 1.5-m conveyor equipped with plastic, foam, or brush rollers followed by 25 previously washed uninoculated tomatoes. Tomato samples were collected after 2 min of both washing and roller conveying, with all 25 uninoculated tomatoes collected individually after conveying. Roller surface samples were collected before and after conveying the uninoculated tomatoes. Both tomato and surface samples were quantitatively examined for Salmonella by direct plating or membrane filtration using xylose lysine Tergitol 4 agar. Regardless of the roller type, Salmonella populations on inoculated tomatoes did not significantly (P < 0.05) decrease during contact with the roller conveyors. After conveying uninoculated tomatoes over contaminated foam rollers, 96% of the 25 tomatoes were cross-contaminated with Salmonella at >100 CFU per tomato. With plastic rollers, 24 and 76% of tomatoes were cross-contaminated with Salmonella at 10 to 100 and 1 to 10 CFU per tomato, respectively. In contrast, only 8% of 25 tomatoes were cross-contaminated with brush rollers with Salmonella populations of 1 to 10 CFU per tomato. Overall, cross-contamination was greatest with foam, followed by plastic and brush rollers (P < 0.05). Adding peroxyacetic acid or chlorine to the wash water significantly decreased cross-contamination during tomato conveying, with chlorine less effective in controlling Salmonella on foam compared with plastic and brush rollers.

Visual Analysis for Detection and Quantification of Pseudomonas cichorii Disease Severity in Tomato Plants.

PubMed

Rajendran, Dhinesh Kumar; Park, Eunsoo; Nagendran, Rajalingam; Hung, Nguyen Bao; Cho, Byoung-Kwan; Kim, Kyung-Hwan; Lee, Yong Hoon

2016-08-01

Pathogen infection in plants induces complex responses ranging from gene expression to metabolic processes in infected plants. In spite of many studies on biotic stress-related changes in host plants, little is known about the metabolic and phenotypic responses of the host plants to Pseudomonas cichorii infection based on image-based analysis. To investigate alterations in tomato plants according to disease severity, we inoculated plants with different cell densities of P. cichorii using dipping and syringe infiltration methods. High-dose inocula (≥ 10(6) cfu/ml) induced evident necrotic lesions within one day that corresponded to bacterial growth in the infected tissues. Among the chlorophyll fluorescence parameters analyzed, changes in quantum yield of PSII (ΦPSII) and non-photochemical quenching (NPQ) preceded the appearance of visible symptoms, but maximum quantum efficiency of PSII (Fv/Fm) was altered well after symptom development. Visible/near infrared and chlorophyll fluorescence hyperspectral images detected changes before symptom appearance at low-density inoculation. The results of this study indicate that the P. cichorii infection severity can be detected by chlorophyll fluorescence assay and hyperspectral images prior to the onset of visible symptoms, indicating the feasibility of early detection of diseases. However, to detect disease development by hyperspectral imaging, more detailed protocols and analyses are necessary. Taken together, change in chlorophyll fluorescence is a good parameter for early detection of P. cichorii infection in tomato plants. In addition, image-based visualization of infection severity before visual damage appearance will contribute to effective management of plant diseases.

Modified expression of alternative oxidase in transgenic tomato and petunia affects the level of tomato spotted wilt virus resistance.

PubMed

Ma, Hao; Song, Congfeng; Borth, Wayne; Sether, Diane; Melzer, Michael; Hu, John

2011-10-20

Tomato spotted wilt virus (TSWV) has a very wide host range, and is transmitted in a persistent manner by several species of thrips. These characteristics make this virus difficult to control. We show here that the over-expression of the mitochondrial alternative oxidase (AOX) in tomato and petunia is related to TSWV resistance. The open reading frame and full-length sequence of the tomato AOX gene LeAox1au were cloned and introduced into tomato 'Healani' and petunia 'Sheer Madness' using Agrobacterium-mediated transformation. Highly expressed AOX transgenic tomato and petunia plants were selfed and transgenic R1 seedlings from 10 tomato lines and 12 petunia lines were used for bioassay. For each assayed line, 22 to 32 tomato R1 progeny in three replications and 39 to 128 petunia progeny in 13 replications were challenged with TSWV. Enzyme-Linked Immunosorbent Assays showed that the TSWV levels in transgenic tomato line FKT4-1 was significantly lower than that of wild-type controls after challenge with TSWV. In addition, transgenic petunia line FKP10 showed significantly less lesion number and smaller lesion size than non-transgenic controls after inoculation by TSWV. In all assayed transgenic tomato lines, a higher percentage of transgenic progeny had lower TSWV levels than non-transgenic plants after challenge with TSWV, and the significantly increased resistant levels of tomato and petunia lines identified in this study indicate that altered expression levels of AOX in tomato and petunia can affect the levels of TSWV resistance.

Modified expression of alternative oxidase in transgenic tomato and petunia affects the level of tomato spotted wilt virus resistance

PubMed Central

2011-01-01

Background Tomato spotted wilt virus (TSWV) has a very wide host range, and is transmitted in a persistent manner by several species of thrips. These characteristics make this virus difficult to control. We show here that the over-expression of the mitochondrial alternative oxidase (AOX) in tomato and petunia is related to TSWV resistance. Results The open reading frame and full-length sequence of the tomato AOX gene LeAox1au were cloned and introduced into tomato 'Healani' and petunia 'Sheer Madness' using Agrobacterium-mediated transformation. Highly expressed AOX transgenic tomato and petunia plants were selfed and transgenic R1 seedlings from 10 tomato lines and 12 petunia lines were used for bioassay. For each assayed line, 22 to 32 tomato R1 progeny in three replications and 39 to 128 petunia progeny in 13 replications were challenged with TSWV. Enzyme-Linked Immunosorbent Assays showed that the TSWV levels in transgenic tomato line FKT4-1 was significantly lower than that of wild-type controls after challenge with TSWV. In addition, transgenic petunia line FKP10 showed significantly less lesion number and smaller lesion size than non-transgenic controls after inoculation by TSWV. Conclusion In all assayed transgenic tomato lines, a higher percentage of transgenic progeny had lower TSWV levels than non-transgenic plants after challenge with TSWV, and the significantly increased resistant levels of tomato and petunia lines identified in this study indicate that altered expression levels of AOX in tomato and petunia can affect the levels of TSWV resistance. PMID:22014312

Photosynthetic Traits of Plants and the Biochemical Profile of Tomato Fruits Are Influenced by Grafting, Salinity Stress, and Growing Season.

PubMed

Marsic, Nina Kacjan; Vodnik, Dominik; Mikulic-Petkovsek, Maja; Veberic, Robert; Sircelj, Helena

2018-06-06

Changes in the photosynthetic traits of plants and metabolic composition of fruits of two tomato cultivars, grafted onto two rootstocks, grown in three salinity levels were studied in two growing periods during the season. Increased salinity stress conditions lowered water potential, stomatal conductance, and transpiration rate of grafted tomato plants, in both growing periods. Water deficit induced stomatal closure, which resulted in stomatal limitation of photosynthesis. The proline content in tomato leaves increased and was closely correlated with salinity. Some of the quality parameters of tomato fruits were affected by rootstock. The sugar/acid ratio was the highest in fruits of 'Belle'/'Maxifort' grafts. With increasing salt stress conditions from 40 to 60 mM NaCl, the lycopene content increased and ascorbic acid content decreased in fruits of 'Gardel'/'Maxifort' grafts, indicating the ability of this scion/rootstock combination to mitigate the toxicity effect of salinity stress. A higher phenolics concentration in fruits from the first growing period may be an additional indicator of stress, caused by higher temperatures and solar radiation, compared with the later period.

Rhizosphere Microbiome Recruited from a Suppressive Compost Improves Plant Fitness and Increases Protection against Vascular Wilt Pathogens of Tomato

PubMed Central

Antoniou, Anastasis; Tsolakidou, Maria-Dimitra; Stringlis, Ioannis A.; Pantelides, Iakovos S.

2017-01-01

Suppressive composts represent a sustainable approach to combat soilborne plant pathogens and an alternative to the ineffective chemical fungicides used against those. Nevertheless, suppressiveness to plant pathogens and reliability of composts are often inconsistent with unpredictable effects. While suppressiveness is usually attributed to the compost’s microorganisms, the mechanisms governing microbial recruitment by the roots and the composition of selected microbial communities are not fully elucidated. Herein, the purpose of the study was to evaluate the impact of a compost on tomato plant growth and its suppressiveness against Fusarium oxysporum f. sp. lycopersici (Foxl) and Verticillium dahliae (Vd). First, growth parameters of tomato plants grown in sterile peat-based substrates including 20 and 30% sterile compost (80P/20C-ST and 70P/30C-ST) or non-sterile compost (80P/20C and 70P/30C) were evaluated in a growth room experiment. Plant height, total leaf surface, and fresh and dry weight of plants grown in the non-sterile compost mixes were increased compared to the plants grown in the sterile compost substrates, indicating the plant growth promoting activity of the compost’s microorganisms. Subsequently, compost’s suppressiveness against Foxl and Vd was evaluated with pathogenicity experiments on tomato plants grown in 70P/30C-ST and 70P/30C substrates. Disease intensity was significantly less in plants grown in the non-sterile compost than in those grown in the sterile compost substrate; AUDPC was 2.3- and 1.4-fold less for Foxl and Vd, respectively. Moreover, fungal quantification in planta demonstrated reduced colonization in plants grown in the non-sterile mixture. To further investigate these findings, we characterized the culturable microbiome attracted by the roots compared to the unplanted compost. Bacteria and fungi isolated from unplanted compost and the rhizosphere of plants were sequence-identified. Community-level analysis revealed

Physiological and Metabolic Responses Triggered by Omeprazole Improve Tomato Plant Tolerance to NaCl Stress

PubMed Central

Rouphael, Youssef; Raimondi, Giampaolo; Lucini, Luigi; Carillo, Petronia; Kyriacou, Marios C.; Colla, Giuseppe; Cirillo, Valerio; Pannico, Antonio; El-Nakhel, Christophe; De Pascale, Stefania

2018-01-01

Interest in the role of small bioactive molecules (< 500 Da) in plants is on the rise, compelled by plant scientists' attempt to unravel their mode of action implicated in stimulating growth and enhancing tolerance to environmental stressors. The current study aimed at elucidating the morphological, physiological and metabolomic changes occurring in greenhouse tomato (cv. Seny) treated with omeprazole (OMP), a benzimidazole inhibitor of animal proton pumps. The OMP was applied at three rates (0, 10, or 100 μM) as substrate drench for tomato plants grown under nonsaline (control) or saline conditions sustained by nutrient solutions of 1 or 75 mM NaCl, respectively. Increasing NaCl concentration from 1 to 75 mM decreased the tomato shoot dry weight by 49% in the 0 μM OMP treatment, whereas the reduction was not significant at 10 or 100 μM of OMP. Treatment of salinized (75 mM NaCl) tomato plants with 10 and especially 100 μM OMP decreased Na+ and Cl− while it increased Ca2+ concentration in the leaves. However, OMP was not strictly involved in ion homeostasis since the K+ to Na+ ratio did not increase under combined salinity and OMP treatment. OMP increased root dry weight, root morphological characteristics (total length and surface), transpiration, and net photosynthetic rate independently of salinity. Metabolic profiling of leaves through UHPLC liquid chromatography coupled to quadrupole-time-of-flight mass spectrometry facilitated identification of the reprogramming of a wide range of metabolites in response to OMP treatment. Hormonal changes involved an increase in ABA, decrease in auxins and cytokinin, and a tendency for GA down accumulation. Cutin biosynthesis, alteration of membrane lipids and heightened radical scavenging ability related to the accumulation of phenolics and carotenoids were observed. Several other stress-related compounds, such as polyamine conjugates, alkaloids and sesquiterpene lactones, were altered in response to OMP. Although a

Tomato progeny inherit resistance to the nematode Meloidogyne javanica linked to plant growth induced by the biocontrol fungus Trichoderma atroviride.

PubMed

Medeiros, Hugo Agripino de; Araújo Filho, Jerônimo Vieira de; Freitas, Leandro Grassi de; Castillo, Pablo; Rubio, María Belén; Hermosa, Rosa; Monte, Enrique

2017-01-10

Root-knot nematodes (RKN) are major crop pathogens worldwide. Trichoderma genus fungi are recognized biocontrol agents and a direct activity of Trichoderma atroviride (Ta) against the RKN Meloidogyne javanica (Mj), in terms of 42% reduction of number of galls (NG), 60% of number of egg masses and 90% of number of adult nematodes inside the roots, has been observed in tomato grown under greenhouse conditions. An in vivo split-root designed experiment served to demonstrate that Ta induces systemic resistance towards Mj, without the need for the organisms to be in direct contact, and significantly reduces NG (20%) and adult nematodes inside tomato roots (87%). The first generation (F1) of Ta-primed tomato plants inherited resistance to RKN; although, the induction of defenses occurred through different mechanisms, and in varying degrees, depending on the Ta-Mj interaction. Plant growth promotion induced by Ta was inherited without compromising the level of resistance to Mj, as the progeny of Ta-primed plants displayed increased size and resistance to Mj without fitness costs. Gene expression results from the defense inductions in the offspring of Ta-primed plants, suggested that an auxin-induced reactive oxygen species production promoted by Ta may act as a major defense strategy during plant growth.

LeMYC2 acts as a negative regulator of blue light mediated photomorphogenic growth, and promotes the growth of adult tomato plants

PubMed Central

2014-01-01

Background Arabidopsis ZBF1/MYC2bHLH transcription factor is a repressor of photomorphogenesis, and acts as a point of cross talk in light, abscisic acid (ABA) and jasmonic acid (JA) signaling pathways. MYC2 also functions as a positive regulator of lateral root development and flowering time under long day conditions. However, the function of MYC2 in growth and development remains unknown in crop plants. Results Here, we report the functional analyses of LeMYC2 in tomato (Lycopersicon esculentum). The amino acid sequence of LeMYC2 showed extensive homology with Arabidopsis MYC2, containing the conserved bHLH domain. To study the function of LeMYC2 in tomato, overexpression and RNA interference (RNAi) LeMYC2 tomato transgenic plants were generated. Examination of seedling morphology, physiological responses and light regulated gene expression has revealed that LeMYC2 works as a negative regulator of blue light mediated photomorphogenesis. Furthermore, LeMYC2 specifically binds to the G-box of LeRBCS-3A promoter. Overexpression of LeMYC2 has led to increased root length with more number of lateral roots. The tomato plants overexpressing LeMYC2 have reduced internode distance with more branches, and display the opposite morphology to RNAi transgenic lines. Furthermore, this study shows that LeMYC2 promotes ABA and JA responsiveness. Conclusions Collectively, this study highlights that working in light, ABA and JA signaling pathways LeMYC2 works as an important regulator for growth and development in tomato plants. PMID:24483714

Microarray Analysis of Tomato Plants Exposed to the Nonviruliferous or Viruliferous Whitefly Vector Harboring Pepper golden mosaic virus

PubMed Central

Musser, Richard O.; Hum-Musser, Sue M.; Gallucci, Matthew; DesRochers, Brittany; Brown, Judith K.

2014-01-01

Abstract Plants are routinely exposed to biotic and abiotic stresses to which they have evolved by synthesizing constitutive and induced defense compounds. Induced defense compounds are usually made, initially, at low levels; however, following further stimulation by specific kinds of biotic and abiotic stresses, they can be synthesized in relatively large amounts to abate the particular stress. cDNA microarray hybridization was used to identify an array of genes that were differentially expressed in tomato plants 15 d after they were exposed to feeding by nonviruliferous whiteflies or by viruliferous whiteflies carrying Pepper golden mosaic virus (PepGMV) ( Begomovirus, Geminiviridae ). Tomato plants inoculated by viruliferous whiteflies developed symptoms characteristic of PepGMV, whereas plants exposed to nonviruliferous whitefly feeding or nonwounded (negative) control plants exhibited no disease symptoms. The microarray analysis yielded over 290 spotted probes, with significantly altered expression of 161 putative annotated gene targets, and 129 spotted probes of unknown identities. The majority of the differentially regulated “known” genes were associated with the plants exposed to viruliferous compared with nonviruliferous whitefly feeding. Overall, significant differences in gene expression were represented by major physiological functions including defense-, pathogen-, photosynthesis-, and signaling-related responses and were similar to genes identified for other insect–plant systems. Viruliferous whitefly-stimulated gene expression was validated by real-time quantitative polymerase chain reaction of selected, representative candidate genes (messenger RNA): arginase, dehydrin, pathogenesis-related proteins 1 and -4, polyphenol oxidase, and several protease inhibitors. This is the first comparative profiling of the expression of tomato plants portraying different responses to biotic stress induced by viruliferous whitefly feeding (with resultant

Differential Control Efficacies of Vitamin Treatments against Bacterial Wilt and Grey Mould Diseases in Tomato Plants.

PubMed

Hong, Jeum Kyu; Kim, Hyeon Ji; Jung, Heesoo; Yang, Hye Ji; Kim, Do Hoon; Sung, Chang Hyun; Park, Chang-Jin; Chang, Seog Won

2016-10-01

Bacterial wilt and grey mould in tomato plants are economically destructive bacterial and fungal diseases caused by Ralstonia solanacearum and Botrytis cinerea , respectively. Various approaches including chemical and biological controls have been attempted to arrest the tomato diseases so far. In this study, in vitro growths of bacterial R. solanacearum and fungal B. cinerea were evaluated using four different vitamins including thiamine (vitamin B1), niacin (vitamin B3), pyridoxine (vitamin B6), and menadione (vitamin K3). In planta efficacies of the four vitamin treatments on tomato protection against both diseases were also demonstrated. All four vitamins showed different in vitro antibacterial activities against R. solanacearum in dose-dependent manners. However, treatment with 2 mM thiamine was only effective in reducing bacterial wilt of detached tomato leaves without phytotoxicity under lower disease pressure (10 6 colony-forming unit [cfu]/ml). Treatment with the vitamins also differentially reduced in vitro conidial germination and mycelial growth of B. cinerea . The four vitamins slightly reduced the conidial germination, and thiamine, pyridoxine and menadione inhibited the mycelial growth of B. cinerea . Menadione began to drastically suppress the conidial germination and mycelial growth by 5 and 0.5 mM, respectively. Grey mould symptoms on the inoculated tomato leaves were significantly reduced by pyridoxine and menadione pretreatments one day prior to the fungal challenge inoculation. These findings suggest that disease-specific vitamin treatment will be integrated for eco-friendly management of tomato bacterial wilt and grey mould.

Differential Control Efficacies of Vitamin Treatments against Bacterial Wilt and Grey Mould Diseases in Tomato Plants

PubMed Central

Hong, Jeum Kyu; Kim, Hyeon Ji; Jung, Heesoo; Yang, Hye Ji; Kim, Do Hoon; Sung, Chang Hyun; Park, Chang-Jin; Chang, Seog Won

2016-01-01

Bacterial wilt and grey mould in tomato plants are economically destructive bacterial and fungal diseases caused by Ralstonia solanacearum and Botrytis cinerea, respectively. Various approaches including chemical and biological controls have been attempted to arrest the tomato diseases so far. In this study, in vitro growths of bacterial R. solanacearum and fungal B. cinerea were evaluated using four different vitamins including thiamine (vitamin B1), niacin (vitamin B3), pyridoxine (vitamin B6), and menadione (vitamin K3). In planta efficacies of the four vitamin treatments on tomato protection against both diseases were also demonstrated. All four vitamins showed different in vitro antibacterial activities against R. solanacearum in dose-dependent manners. However, treatment with 2 mM thiamine was only effective in reducing bacterial wilt of detached tomato leaves without phytotoxicity under lower disease pressure (106 colony-forming unit [cfu]/ml). Treatment with the vitamins also differentially reduced in vitro conidial germination and mycelial growth of B. cinerea. The four vitamins slightly reduced the conidial germination, and thiamine, pyridoxine and menadione inhibited the mycelial growth of B. cinerea. Menadione began to drastically suppress the conidial germination and mycelial growth by 5 and 0.5 mM, respectively. Grey mould symptoms on the inoculated tomato leaves were significantly reduced by pyridoxine and menadione pretreatments one day prior to the fungal challenge inoculation. These findings suggest that disease-specific vitamin treatment will be integrated for eco-friendly management of tomato bacterial wilt and grey mould. PMID:27721697

Solubilisation of Phosphate and Micronutrients by Trichoderma harzianum and Its Relationship with the Promotion of Tomato Plant Growth

PubMed Central

Pang, Guan; Shen, Qi-Rong; Li, Rong; Chen, Wei

2015-01-01

Trichoderma harzianum strain SQR-T037 is a biocontrol agent that has been shown to enhance the uptake of nutrients (macro- and microelements) by plants in fields. The objective of this study was to investigate the contribution of SQR-T037 to P and microelement (Fe, Mn, Cu and Zn) nutrition in tomato plants grown in soil and in hydroponic conditions. Inoculation with SQR-T037 significantly improved the biomass and nutrient uptake of tomato seedlings grown in a nutrient-limiting soil. So we investigated the capability of SQR-T037 to solubilise sparingly soluble minerals in vitro via four known mechanisms: acidification by organic acids, chelation by siderophores, redox by ferric reductase and hydrolysis by phytase. SQR-T037 was able to solubilise phytate, Fe2O3, CuO, and metallic Zn but not Ca3(PO4)2 or MnO2. Organic acids, including lactic acid, citric acid, tartaric acid and succinic acid, were detected by HPLC and LC/MS in two Trichoderma cultures. Additionally, we inoculated tomato seedlings with SQR-T037 using a hydroponic system with specific nutrient deficiencies (i.e., nutrient solutions deficient in P, Fe, Cu or Zn and supplemented with their corresponding solid minerals) to better study the effects of Trichoderma inoculation on plant growth and nutrition. Inoculated seedlings grown in Cu-deficient hydroponic conditions exhibited increases in dry plant biomass (92%) and Cu uptake (42%) relative to control plants. However, we did not observe a significant effect on seedling biomass in plants grown in the Fe- and Zn-deficient hydroponic conditions; by contrast, the biomass decreased by 82% in the P-deficient hydroponic condition. Thus, we demonstrated that Trichoderma SQR-T037 competed for P (phytate) and Zn with tomato seedlings by suppressing root development, releasing phytase and/or chelating minerals. The results of this study suggest that the induction of increased or suppressed plant growth occurs through the direct effect of T. harzianum on root

Solubilisation of Phosphate and Micronutrients by Trichoderma harzianum and Its Relationship with the Promotion of Tomato Plant Growth.

PubMed

Li, Rui-Xia; Cai, Feng; Pang, Guan; Shen, Qi-Rong; Li, Rong; Chen, Wei

2015-01-01

Trichoderma harzianum strain SQR-T037 is a biocontrol agent that has been shown to enhance the uptake of nutrients (macro- and microelements) by plants in fields. The objective of this study was to investigate the contribution of SQR-T037 to P and microelement (Fe, Mn, Cu and Zn) nutrition in tomato plants grown in soil and in hydroponic conditions. Inoculation with SQR-T037 significantly improved the biomass and nutrient uptake of tomato seedlings grown in a nutrient-limiting soil. So we investigated the capability of SQR-T037 to solubilise sparingly soluble minerals in vitro via four known mechanisms: acidification by organic acids, chelation by siderophores, redox by ferric reductase and hydrolysis by phytase. SQR-T037 was able to solubilise phytate, Fe2O3, CuO, and metallic Zn but not Ca3(PO4)2 or MnO2. Organic acids, including lactic acid, citric acid, tartaric acid and succinic acid, were detected by HPLC and LC/MS in two Trichoderma cultures. Additionally, we inoculated tomato seedlings with SQR-T037 using a hydroponic system with specific nutrient deficiencies (i.e., nutrient solutions deficient in P, Fe, Cu or Zn and supplemented with their corresponding solid minerals) to better study the effects of Trichoderma inoculation on plant growth and nutrition. Inoculated seedlings grown in Cu-deficient hydroponic conditions exhibited increases in dry plant biomass (92%) and Cu uptake (42%) relative to control plants. However, we did not observe a significant effect on seedling biomass in plants grown in the Fe- and Zn-deficient hydroponic conditions; by contrast, the biomass decreased by 82% in the P-deficient hydroponic condition. Thus, we demonstrated that Trichoderma SQR-T037 competed for P (phytate) and Zn with tomato seedlings by suppressing root development, releasing phytase and/or chelating minerals. The results of this study suggest that the induction of increased or suppressed plant growth occurs through the direct effect of T. harzianum on root

Application of inorganic carrier-based formulations of fluorescent pseudomonads and Piriformospora indica on tomato plants and evaluation of their efficacy.

PubMed

Sarma, M V R K; Kumar, V; Saharan, K; Srivastava, R; Sharma, A K; Prakash, A; Sahai, V; Bisaria, V S

2011-08-01

Fluorescent pseudomonads are widely used as bioinoculants for improving plant growth and controlling phytopathogenic fungi. Piriformospora indica (Pi), a symbiotic root endophyte, also has beneficial effects on a number of plants. The present study focuses on the improvement of growth yields of tomato plants and control of Fusarium wilt using inorganic carrier-based formulations of two fluorescent pseudomonad strains (R62 and R81) and Pi. The inorganic carrier-based formulations of pseudomonad strains and Pi were tested for plant growth promotion of tomato plants under glass house and field conditions. In controlled glass house experiments, 8·8-fold increase in dry root weight and 8·6-fold increase in dry shoot weight were observed with talcum powder-based consortium formulation of R81 and Pi. Field trial experiments ascertained the glfass house results with a considerable amount of increase in plant growth responses, and amongst all the treatments, R81 + Pi treatment performed consistently well in field conditions with an increase of 2·6-, 3·1- and 3·9-fold increase in dry root weight, shoot weight and fruit yield, respectively. The fluorescent pseudomonad R81 and Pi also acted as biocontrol agents, as their treatments could control the incidence of wilt disease caused by Fusarium oxysporum f.sp. lycopersici in tomato plants under glass house conditions. The culture broths of pseudomonads R62, R81 and Pi were successfully used for development of talcum- and vermiculite-based bioinoculant formulations. In controlled glasshouse experiments, the talcum-based bioinoculant formulations performed significantly better over vermiculite-based formulations. In field experiments the talcum-based consortium formulation of pseudomonad R81 and Pi was most effective. This study suggests that the formulations of pseudomonad strains (R62 and R81) and Pi can be used as bioinoculants for improving the productivity of tomato plants. The application of such formulations is a step

Tomatoes in Space

NASA Technical Reports Server (NTRS)

2004-01-01

BioServe researcher Dr. Yi Li first flew plant experiments on board STS-63. Li discovered that exposure to microgravity increased a particular hormone concentration in plants. Since that time, Li has been able to manipulate this phenomenon and grow fruits, such as tomatoes, that overproduce the hormone, and these plants bear larger seedless fruit in the absence of pollination.

Culture of the Tomato Micro-Tom Cultivar in Greenhouse.

PubMed

Rothan, Christophe; Just, Daniel; Fernandez, Lucie; Atienza, Isabelle; Ballias, Patricia; Lemaire-Chamley, Martine

2016-01-01

Micro-Tom tomato cultivar is particularly adapted to the development of genomic approaches in tomato. Here, we describe the culture of this plant in greenhouse, including climate regulation, seed sowing and watering, vegetative development, plant maintenance, including treatment of phytosanitary problems, and reproductive development.

First Complete Genome Sequence of an Isolate of Tomato Mottle Mosaic Virus Infecting Plants of Solanum lycopersicum in South America.

PubMed

Nagai, Alice; Duarte, Lígia M L; Chaves, Alexandre L R; Alexandre, Maria A V; Ramos-González, Pedro L; Chabi-Jesus, Camila; Harakava, Ricardo; Dos Santos, Déborah Y A C

2018-05-10

The complete nucleotide sequence of an isolate of tomato mottle mosaic virus (ToMMV) was determined. The virus, originally isolated from symptomatic tomato plants found in a county near the city of São Paulo, Brazil, has a genome with 99% nucleotide sequence identity with ToMMV from Mexico, China, Spain, and the United States. Copyright © 2018 Nagai et al.

The Role of Endogenous Strigolactones and Their Interaction with ABA during the Infection Process of the Parasitic Weed Phelipanche ramosa in Tomato Plants

PubMed Central

Cheng, Xi; Floková, Kristýna; Bouwmeester, Harro; Ruyter-Spira, Carolien

2017-01-01

The root parasitic plant species Phelipanche ramosa, branched broomrape, causes severe damage to economically important crops such as tomato. Its seed germination is triggered by host-derived signals upon which it invades the host root. In tomato, strigolactones (SLs) are the main germination stimulants for P. ramosa. Therefore, the development of low SL-producing lines may be an approach to combat the parasitic weed problem. However, since SLs are also a plant hormone controlling many aspects of plant development, SL deficiency may also have an effect on post-germination stages of the infection process, during the parasite-host interaction. In this study, we show that SL-deficient tomato plants (Solanum lycopersicum; SlCCD8 RNAi lines), infected with pre-germinated P. ramosa seeds, display an increased infection level and faster development of the parasite, which suggests a positive role for SLs in the host defense against parasitic plant invasion. Furthermore, we show that SL-deficient tomato plants lose their characteristic SL-deficient phenotype during an infection with P. ramosa through a reduction in the number of internodes and the number and length of secondary branches. Infection with P. ramosa resulted in increased levels of abscisic acid (ABA) in the leaves and roots of both wild type and SL-deficient lines. Upon parasite infection, the level of the conjugate ABA-glucose ester (ABA-GE) also increased in leaves of both wild type and SL-deficient lines and in roots of one SL-deficient line. The uninfected SL-deficient lines had a higher leaf ABA-GE level than the wild type. Despite the high levels of ABA, stomatal aperture and water loss rate were not affected by parasite infection in the SL-deficient line, while in wild type tomato stomatal aperture and water loss increased upon infection. Future studies are needed to further underpin the role that SLs play in the interaction of hosts with parasitic plants and which other plant hormones interact with the

The Role of Endogenous Strigolactones and Their Interaction with ABA during the Infection Process of the Parasitic Weed Phelipanche ramosa in Tomato Plants.

PubMed

Cheng, Xi; Floková, Kristýna; Bouwmeester, Harro; Ruyter-Spira, Carolien

2017-01-01

The root parasitic plant species Phelipanche ramosa , branched broomrape, causes severe damage to economically important crops such as tomato. Its seed germination is triggered by host-derived signals upon which it invades the host root. In tomato, strigolactones (SLs) are the main germination stimulants for P. ramosa . Therefore, the development of low SL-producing lines may be an approach to combat the parasitic weed problem. However, since SLs are also a plant hormone controlling many aspects of plant development, SL deficiency may also have an effect on post-germination stages of the infection process, during the parasite-host interaction. In this study, we show that SL-deficient tomato plants ( Solanum lycopersicum; SlCCD8 RNAi lines), infected with pre-germinated P. ramosa seeds, display an increased infection level and faster development of the parasite, which suggests a positive role for SLs in the host defense against parasitic plant invasion. Furthermore, we show that SL-deficient tomato plants lose their characteristic SL-deficient phenotype during an infection with P. ramosa through a reduction in the number of internodes and the number and length of secondary branches. Infection with P. ramosa resulted in increased levels of abscisic acid (ABA) in the leaves and roots of both wild type and SL-deficient lines. Upon parasite infection, the level of the conjugate ABA-glucose ester (ABA-GE) also increased in leaves of both wild type and SL-deficient lines and in roots of one SL-deficient line. The uninfected SL-deficient lines had a higher leaf ABA-GE level than the wild type. Despite the high levels of ABA, stomatal aperture and water loss rate were not affected by parasite infection in the SL-deficient line, while in wild type tomato stomatal aperture and water loss increased upon infection. Future studies are needed to further underpin the role that SLs play in the interaction of hosts with parasitic plants and which other plant hormones interact with

Effects of foliar applied nickel on tomato plants. [Lycopersicon esculentum

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cash, R.C.; Leone, I.A.

Shoot-applied nickel (Ni) treatments produced symptomatology, foliar Ni accumulation, and cytological changes in tomato (Lycopersicon esculentum Mill.) similar to those caused by treatments with root-applied nickel (Ni). Leaf damage resulting from 100 ..mu..g/ml foliar Ni-treatments consisted of interveinal chlorosis and spotting necrosis which appeared histologically as tissue collapse, cell clumping, and chloroplast disintegration. Shoot-treated plants accumulated more Ni in leaves than in roots; whereas the reverse was true in root-treated plants. Interference with root-to-shoot manganese translocation was attributed to attenuated vascular tissue and phloem blockage. Evidence of reduced nutrient transport and inhibited meristem activity due to Ni toxicity presents amore » potential for crop damage from excessive Ni in the atmosphere as well as in the soil environment.« less

Effect of cobalt ferrite (CoFe2O4) nanoparticles on the growth and development of Lycopersicon lycopersicum (tomato plants).

PubMed

López-Moreno, Martha L; Avilés, Leany Lugo; Pérez, Nitza Guzmán; Irizarry, Bianca Álamo; Perales, Oscar; Cedeno-Mattei, Yarilyn; Román, Félix

2016-04-15

Nanoparticles (NPs) have been synthetized and studied to be incorporated in many industrial and medical applications in recent decades. Due to their different physical and chemical properties compared with bulk materials, researchers are focused to understand their interactions with the surroundings. Living organisms such as plants are exposed to these materials and they are able to tolerate different concentrations and types of NPs. Cobalt ferrite (CoFe2O4) NPs are being studied for their application in medical sciences because of their high coercivity, anisotropy, and large magnetostriction. These properties are desirable in magnetic resonance imaging, drug delivery, and cell labeling. This study is aimed to explore the tolerance of Solanum lycopersicum L. (tomato) plants to CoFe2O4 NPs. Tomato plants were grown in hydroponic media amended with CoFe2O4 nanoparticles in a range from 0 to 1000mgL(-1). Exposure to CoFe2O4 NPs did not affect germination and growth of plants. Uptake of Fe and Co inside plant tissues increased as CoFe2O4 nanoparticle concentration was increased in the media. Mg uptake in plant leaves reached its maximum level of 4.9mgg(-1) DW (dry weight) at 125mgL(-1) of CoFe2O4 NPs exposure and decreased at high CoFe2O4 NPs concentrations. Similar pattern was observed for Ca uptake in leaves where the maximum concentration found was 10mgg(-1) DW at 125mgL(-1) of CoFe2O4 NPs exposure. Mn uptake in plant leaves was higher at 62.5mgL(-1) of CoFe2O4 NPs compared with 125 and 250mgL(-1) treatments. Catalase activity in tomato roots and leaves decreased in plants exposed to CoFe2O4 NPs. Tomato plants were able to tolerate CoFe2O4 NPs concentrations up to 1000mgL(-1) without visible toxicity symptoms. Macronutrient uptake in plants was affected when plants were exposed to 250, 500 and 1000mgL(-1) of CoFe2O4 NPs. Published by Elsevier B.V.

Acclimation of two tomato species to high atmospheric CO sub 2 : I. Sugar and starch concentrations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yelle, S.; Beeson, R.C. Jr.; Trudel, M.J.

Lycopersicon esculentum Mill. cv Vedettos and Lycopersicon chmielewskii Rick, LA1028, were exposed to two CO{sub 2} concentrations for 10 weeks. Tomato plants grown at 900 microliters per liter contained more starch and more sugars than the control. However, we found no significant accumulation of starch and sugars in the young leaves of L. esculentum exposed to high CO{sub 2}. Carbon exchange rates were significantly higher in CO{sub 2}-enriched plants for the first few weeks of treatment but thereafter decreased as tomato plants acclimated to high atmospheric CO{sub 2}. This indicates that the long-term decline of photosynthetic efficiency of leaf 5more » cannot be attributed to an accumulation of sugar and/or starch. The average concentration of starch in leaves 5 and 9 was always higher in L. esculentum than in L. chmielewskii (151.7% higher). A higher proportion of photosynthates was directed into starch for L. esculentum than for L. chmielewskii. However, these characteristics did not improve the long-term photosynthetic efficiency of L. chmielewskii grown at high CO{sub 2} when compared with L. esculentum. The chloroplasts of tomato plants exposed to the higher CO{sub 2} concentration exhibited a marked accumulation of starch. The results reported here suggest that starch and/or sugar accumulation under high CO{sub 2} cannot entirely explain the loss of photosynthetic efficiency of high CO{sub 2}-grown plants.« less

Ethylene emission and PR protein synthesis in ACC deaminase producing Methylobacterium spp. inoculated tomato plants (Lycopersicon esculentum Mill.) challenged with Ralstonia solanacearum under greenhouse conditions.

PubMed

Yim, Woojong; Seshadri, Sundaram; Kim, Kiyoon; Lee, Gillseung; Sa, Tongmin

2013-06-01

Bacteria of genus Methylobacterium have been found to promote plant growth and regulate the level of ethylene in crop plants. This work is aimed to test the induction of defense responses in tomato against bacterial wilt by stress ethylene level reduction mediated by the ACC deaminase activity of Methylobacterium strains. Under greenhouse conditions, the disease index value in Methylobacterium sp. inoculated tomato plants was lower than control plants. Plants treated with Methylobacterium sp. challenge inoculated with Ralstonia solanacearum (RS) showed significantly reduced disease symptoms and lowered ethylene emission under greenhouse condition. The ACC and ACO (1-aminocyclopropane-1-carboxylate oxidase) accumulation in tomato leaves were significantly reduced with Methylobacterium strains inoculation. While ACC oxidase gene expression was found higher in plants treated with R. solanacearum than Methylobacterium sp. treatment, PR proteins related to induced systemic resistance like β-1,3-glucanase, PAL, PO and PPO were increased in Methylobacterium sp. inoculated plants. A significant increase in β-1,3-glucanase and PAL gene expression was found in all the Methylobacterium spp. treatments compared to the R. solanacearum treatment. This study confirms the activity of Methylobacterium sp. in increasing the defense enzymes by modulating the ethylene biosynthesis pathway and suggests the use of methylotrophic bacteria as potential biocontrol agents in tomato cultivation. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

An attack of the plant parasite Cuscuta reflexa induces the expression of attAGP, an attachment protein of the host tomato.

PubMed

Albert, Markus; Belastegui-Macadam, Xana; Kaldenhoff, Ralf

2006-11-01

Dodder or Cuscutaceae are holoparasitic plants subsisting on other dicotyledonous plants. The infection process is initiated by adherence of Cuscuta prehaustoria to the host surface, followed by penetration attempts by hyphae. In the case of a successful infection, these organs connect the parasite's vascular tissue to that of the host. Here we show that contact of Cuscuta reflexa prehaustoria to tomato induces the expression of a new arabinogalactan protein (AGP), attAGP, in the tomato precisely at the site of dodder attack. We show that attAGP is a plasma membrane-bound cell wall-localized protein. Using the RNAi technique and attAGP-targeted virus-induced gene silencing, we observed a correlation between attAGP expression level and force of attachment of the parasite to host tomatoes. If the expression level of attAGP was reduced, the C. reflexa attachment capability was significantly reduced, too. We conclude that C. reflexa infection induced a signal in the host leading to expression of tomato attAGP, which promotes the parasite's adherence.

Enhanced tomato disease resistance primed by arbuscular mycorrhizal fungus

PubMed Central

Song, Yuanyuan; Chen, Dongmei; Lu, Kai; Sun, Zhongxiang; Zeng, Rensen

2015-01-01

Roots of most terrestrial plants form symbiotic associations (mycorrhiza) with soil- borne arbuscular mycorrhizal fungi (AMF). Many studies show that mycorrhizal colonization enhances plant resistance against pathogenic fungi. However, the mechanism of mycorrhiza-induced disease resistance remains equivocal. In this study, we found that mycorrhizal inoculation with AMF Funneliformis mosseae significantly alleviated tomato (Solanum lycopersicum Mill.) early blight disease caused by Alternaria solani Sorauer. AMF pre-inoculation led to significant increases in activities of β-1,3-glucanase, chitinase, phenylalanine ammonia-lyase (PAL) and lipoxygenase (LOX) in tomato leaves upon pathogen inoculation. Mycorrhizal inoculation alone did not influence the transcripts of most genes tested. However, pathogen attack on AMF-inoculated plants provoked strong defense responses of three genes encoding pathogenesis-related proteins, PR1, PR2, and PR3, as well as defense-related genes LOX, AOC, and PAL, in tomato leaves. The induction of defense responses in AMF pre-inoculated plants was much higher and more rapid than that in un-inoculated plants in present of pathogen infection. Three tomato genotypes: a Castlemart wild-type (WT) plant, a jasmonate (JA) biosynthesis mutant (spr2), and a prosystemin-overexpressing 35S::PS plant were used to examine the role of the JA signaling pathway in AMF-primed disease defense. Pathogen infection on mycorrhizal 35S::PS plants led to higher induction of defense-related genes and enzymes relative to WT plants. However, pathogen infection did not induce these genes and enzymes in mycorrhizal spr2 mutant plants. Bioassays showed that 35S::PS plants were more resistant and spr2 plants were more susceptible to early blight compared with WT plants. Our finding indicates that mycorrhizal colonization enhances tomato resistance to early blight by priming systemic defense response, and the JA signaling pathway is essential for mycorrhiza

Enhanced tomato disease resistance primed by arbuscular mycorrhizal fungus.

PubMed

Song, Yuanyuan; Chen, Dongmei; Lu, Kai; Sun, Zhongxiang; Zeng, Rensen

2015-01-01

Roots of most terrestrial plants form symbiotic associations (mycorrhiza) with soil- borne arbuscular mycorrhizal fungi (AMF). Many studies show that mycorrhizal colonization enhances plant resistance against pathogenic fungi. However, the mechanism of mycorrhiza-induced disease resistance remains equivocal. In this study, we found that mycorrhizal inoculation with AMF Funneliformis mosseae significantly alleviated tomato (Solanum lycopersicum Mill.) early blight disease caused by Alternaria solani Sorauer. AMF pre-inoculation led to significant increases in activities of β-1,3-glucanase, chitinase, phenylalanine ammonia-lyase (PAL) and lipoxygenase (LOX) in tomato leaves upon pathogen inoculation. Mycorrhizal inoculation alone did not influence the transcripts of most genes tested. However, pathogen attack on AMF-inoculated plants provoked strong defense responses of three genes encoding pathogenesis-related proteins, PR1, PR2, and PR3, as well as defense-related genes LOX, AOC, and PAL, in tomato leaves. The induction of defense responses in AMF pre-inoculated plants was much higher and more rapid than that in un-inoculated plants in present of pathogen infection. Three tomato genotypes: a Castlemart wild-type (WT) plant, a jasmonate (JA) biosynthesis mutant (spr2), and a prosystemin-overexpressing 35S::PS plant were used to examine the role of the JA signaling pathway in AMF-primed disease defense. Pathogen infection on mycorrhizal 35S::PS plants led to higher induction of defense-related genes and enzymes relative to WT plants. However, pathogen infection did not induce these genes and enzymes in mycorrhizal spr2 mutant plants. Bioassays showed that 35S::PS plants were more resistant and spr2 plants were more susceptible to early blight compared with WT plants. Our finding indicates that mycorrhizal colonization enhances tomato resistance to early blight by priming systemic defense response, and the JA signaling pathway is essential for mycorrhiza

Effect of water withdrawal on formation of free radical, proline accumulation and activities of antioxidant enzymes in ZAT12-transformed transgenic tomato plants.

PubMed

Chandra Rai, Avinash; Singh, Major; Shah, Kavita

2012-12-01

Water stress often leads to the accumulation of reactive oxygen species (ROS) and their excessive production alters the activities of enzymes involved in their removal. ZAT12 is a member of stress-responsive C(2)H(2) type Zinc Finger Protein (ZFP) reported to control the expression of several stress-activated genes in plants through ROS signaling. The ZAT12-transformed tomato lines (cv. H-86 variety Kashi Vishesh) when subjected to water withdrawal for 7, 14 and 21 days revealed significant and consistent changes in activities of enzymes SOD, CAT, APX, GR and POD paralleled with an increased proline levels. Unlike that in wild-type tomato, the leaf superoxide anion and hydrogen peroxide concentrations in the transformed tomato plants did not alter much, suggesting a well regulated formation of free radicals suppressing oxidative stress in the latter. Results suggest BcZAT12-transformed tomato lines ZT1, ZT2 and ZT6 to be better adapted to drought stress tolerance by accumulation of osmolyte proline and increased antioxidant response triggered by the ZAT12 gene. Therefore, the ZAT12-transformed tomato cv. H-86 lines will prove useful for higher yield of tomato crop in regions affected with severe drought stress. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

Total Phenolic, Flavonoid, Tomatine, and Tomatidine Contents and Antioxidant and Antimicrobial Activities of Extracts of Tomato Plant

PubMed Central

Silva-Beltrán, Norma Patricia; Ruiz-Cruz, Saul; Cira-Chávez, Luis Alberto; Estrada-Alvarado, María Isabel; Ornelas-Paz, José de Jesús; López-Mata, Marco Antonio; Del-Toro-Sánchez, Carmen Lizette; Ayala-Zavala, J. Fernando; Márquez-Ríos, Enrique

2015-01-01

The purpose of this study was to evaluate the antioxidant and antimicrobial properties of extracts of different fractions of two tomato plant cultivars. The stems, roots, leaves, and whole-plant fractions were evaluated. Tomatine and tomatidine were identified by HPLC-DAD. The leaf extracts from the two varieties showed the highest flavonoids, chlorophyll, carotenoids, and total phenolics contents and the highest antioxidant activity determined by DPPH, ABTS, and ORAC. A positive correlation was observed between the antioxidant capacities of the extracts and the total phenolic, flavonoid, and chlorophyll contents. The Pitenza variety extracts inhibited the growth of pathogens such as E. coli O157:H7, Salmonella Typhimurium, Staphylococcus aureus, and Listeria ivanovii, yielding inhibition halos of 8.0 to 12.9 mm in diameter and MIC values of 12.5 to 3.125 mg/mL. These results suggest that tomato plant shows well potential as sources of various bioactive compounds, antioxidants, and antimicrobials. PMID:26609308

Induced Resistance to Meloidogyne hapla by other Meloidogyne species on Tomato and Pyrethrum Plants

PubMed Central

Ogallo, J. L.; McClure, M. A.

1995-01-01

Advance inoculation of the tomato cv. Celebrity or the pyrethrum clone 223 with host-incompatible Meloidogyne incognita or M. javanica elicited induced resistance to host-compatible M. hapla in pot and field experiments. Induced resistance increased with the length of the time between inoculations and with the population density of the induction inoculum. Optimum interval before challenge inoculation, or population density of inoculum for inducing resistance, was 10 days, or 5,000 infective nematodes per 500-cm³ pot. The induced resistance suppressed population increase of M. hapla by 84% on potted tomato, 72% on potted pyrethrum, and 55% on field-grown pyrethrum seedlings, relative to unprotected treatments. Pyrethrum seedlings inoculated with M. javanica 10 days before infection with M. hapla were not stunted, whereas those that did not receive the advance inoculum were stunted 33% in pots and 36% in field plots. The results indicated that advance infection of plants with incompatible or mildly virulent nematode species induced resistance to normally compatible nematodes and that the induced resistance response may have potential as a biological control method for plant nematodes. PMID:19277310

Tolerance to Stress Combination in Tomato Plants: New Insights in the Protective Role of Melatonin.

PubMed

Martinez, Vicente; Nieves-Cordones, Manuel; Lopez-Delacalle, Maria; Rodenas, Reyes; Mestre, Teresa C; Garcia-Sanchez, Francisco; Rubio, Francisco; Nortes, Pedro A; Mittler, Ron; Rivero, Rosa M

2018-02-28

Abiotic stresses such as drought, heat or salinity are major causes of yield loss worldwide. Recent studies have revealed that the acclimation of plants to a combination of different environmental stresses is unique and therefore cannot be directly deduced from studying the response of plants to each of the different stresses applied individually. The efficient detoxification of reactive oxygen species (ROS) is thought to play a key role in enhancing the tolerance of plants to abiotic stresses. Here, we report on the role of melatonin in the protection of the photosynthetic apparatus through the increase in ROS detoxification in tomato plants grown under the combination of salinity and heat, two of the most common abiotic stresses known to act jointly. Plants treated with exogenous melatonin showed a different modulation in the expression on some antioxidant-related genes and their related enzymes. More specifically, ascorbate peroxidase, glutathione reductase, glutathione peroxidase and phospholipid hydroperoxide glutathione peroxidase (APX, GR, GPX and Ph-GPX, resepctively) showed an antagonistic regulation as compared to plants that did not receive melatonin. This translated into a better antioxidant capacity and to a lesser ROS accumulation under stress combination. The performance of the photosynthesis parameters and the photosystems was also increased in plants treated with exogenous melatonin under the combination of salinity and heat. In accordance with these findings, tomato plants treated with melatonin were found to grow better under stress combination that the non-treated ones. Our study highlights the important role that exogenous melatonin plays in the acclimation of plants to a combination of two different abiotic stresses, and how this compound can specifically regulate oxidative stress-related genes and enzymes to increase plant tolerance.

Hijacking common mycorrhizal networks for herbivore-induced defence signal transfer between tomato plants

PubMed Central

Song, Yuan Yuan; Ye, Mao; Li, Chuanyou; He, Xinhua; Zhu-Salzman, Keyan; Wang, Rui Long; Su, Yi Juan; Luo, Shi Ming; Zeng, Ren Sen

2014-01-01

Common mycorrhizal networks (CMNs) link multiple plants together. We hypothesized that CMNs can serve as an underground conduit for transferring herbivore-induced defence signals. We established CMN between two tomato plants in pots with mycorrhizal fungus Funneliformis mosseae, challenged a ‘donor' plant with caterpillar Spodoptera litura, and investigated defence responses and insect resistance in neighbouring CMN-connected ‘receiver' plants. After CMN establishment caterpillar infestation on ‘donor' plant led to increased insect resistance and activities of putative defensive enzymes, induction of defence-related genes and activation of jasmonate (JA) pathway in the ‘receiver' plant. However, use of a JA biosynthesis defective mutant spr2 as ‘donor' plants resulted in no induction of defence responses and no change in insect resistance in ‘receiver' plants, suggesting that JA signalling is required for CMN-mediated interplant communication. These results indicate that plants are able to hijack CMNs for herbivore-induced defence signal transfer and interplant defence communication. PMID:24468912

Complete genome sequence of Southern tomato virus naturally infecting tomatoes in Bangladesh using small RNA deep sequencing

USDA-ARS?s Scientific Manuscript database

The complete genome sequence of a Southern tomato virus (STV) isolate on tomato plants in a seed production field in Bangladesh was obtained for the first time using next generation sequencing. The identified isolate STV_BD-13 shares high degree of sequence identity (99%) with several known STV isol...

Fungal cell wall polymer based nanoparticles in protection of tomato plants from wilt disease caused by Fusarium oxysporum f.sp. lycopersici.

PubMed

Sathiyabama, M; Charles, R Einstein

2015-11-20

Cell wall polymer (chitosan) was isolated from Fusarium oxysporum f.sp. lycopersici. They were cross linked with sodium tripolyphosphate (TPP) to synthesize nanoparticles (CWP-NP). The nanoparticles were characterized by FTIR, DLS, SEM, XRD and NMR analyses. The isolated CWP-NP exhibit antifungal activity under in vitro condition. The foliar application of the CWP-NP to tomato plants challenged with F. oxysporum f. sp. lycopersici showed delay in wilt disease symptom expression and reduce the wilt disease severity. Treated plants also showed enhanced yield. These results suggested the role of the CWP-NP in protecting tomato plants from F. oxysporum f.sp. lycopersici infection. Copyright © 2015 Elsevier Ltd. All rights reserved.

Pseudomonas syringae pv. tomato DC3000: a model pathogen for probing disease susceptibility and hormone signaling in plants.

PubMed

Xin, Xiu-Fang; He, Sheng Yang

2013-01-01

Since the early 1980s, various strains of the gram-negative bacterial pathogen Pseudomonas syringae have been used as models for understanding plant-bacterial interactions. In 1991, a P. syringae pathovar tomato (Pst) strain, DC3000, was reported to infect not only its natural host tomato but also Arabidopsis in the laboratory, a finding that spurred intensive efforts in the subsequent two decades to characterize the molecular mechanisms by which this strain causes disease in plants. Genomic analysis shows that Pst DC3000 carries a large repertoire of potential virulence factors, including proteinaceous effectors that are secreted through the type III secretion system and a polyketide phytotoxin called coronatine, which structurally mimics the plant hormone jasmonate (JA). Study of Pst DC3000 pathogenesis has not only provided several conceptual advances in understanding how a bacterial pathogen employs type III effectors to suppress plant immune responses and promote disease susceptibility but has also facilitated the discovery of the immune function of stomata and key components of JA signaling in plants. The concepts derived from the study of Pst DC3000 pathogenesis may prove useful in understanding pathogenesis mechanisms of other plant pathogens.

Impact of post-infiltration soil aeration at different growth stages of sub-surface trickle-irrigated tomato plants

NASA Astrophysics Data System (ADS)

Li, Yuan; Jia, Zong-xia; Niu, Wen-Quan; Wang, Jing-wei

2016-07-01

Sensitivity to low rhizosphere soil aeration may change over time and therefore plant response may also depend on different growth stages of a crop. This study quantified effects of soil aeration during 5 different periods, on growth and yield of trickle-irrigated potted single tomato plants. Irrigation levels were 0.6 to 0.7 (low level) or 0.7 to 0.8 (high level) of total water holding capacity of the pots. Soil was aerated by injecting 2.5 l of air into each pot through the drip tubing immediately after irrigation. Fresh fruit yield, above ground plant dry weight, plant height, and leaf area index response to these treatments were measured. For all these 4 response variables, means of post-infiltration aeration between 58 to 85 days after sowing were 13.4, 43.5, 13.7, and 37.7% higher than those for the non-aerated pots, respectively. The results indicated that: post-infiltration soil aeration can positively impact the yield and growth of sub-surface trickle-irrigated potted tomato plants; positive effects on plant growth can be obtained with aeration during the whole growth period or with aeration for partial periods; positive growth effects of partial periods of aeration appears to persist and result in yield benefit.

Convergence of developmental mutants into a single tomato model system: 'Micro-Tom' as an effective toolkit for plant development research

PubMed Central

2011-01-01

Background The tomato (Solanum lycopersicum L.) plant is both an economically important food crop and an ideal dicot model to investigate various physiological phenomena not possible in Arabidopsis thaliana. Due to the great diversity of tomato cultivars used by the research community, it is often difficult to reliably compare phenotypes. The lack of tomato developmental mutants in a single genetic background prevents the stacking of mutations to facilitate analysis of double and multiple mutants, often required for elucidating developmental pathways. Results We took advantage of the small size and rapid life cycle of the tomato cultivar Micro-Tom (MT) to create near-isogenic lines (NILs) by introgressing a suite of hormonal and photomorphogenetic mutations (altered sensitivity or endogenous levels of auxin, ethylene, abscisic acid, gibberellin, brassinosteroid, and light response) into this genetic background. To demonstrate the usefulness of this collection, we compared developmental traits between the produced NILs. All expected mutant phenotypes were expressed in the NILs. We also created NILs harboring the wild type alleles for dwarf, self-pruning and uniform fruit, which are mutations characteristic of MT. This amplified both the applications of the mutant collection presented here and of MT as a genetic model system. Conclusions The community resource presented here is a useful toolkit for plant research, particularly for future studies in plant development, which will require the simultaneous observation of the effect of various hormones, signaling pathways and crosstalk. PMID:21714900

Effect of Post-Infiltration Soil Aeration at Different Growth Stages on Growth and Fruit Quality of Drip-Irrigated Potted Tomato Plants (Solanum lycopersicum).

PubMed

Li, Yuan; Jia, Zongxia; Niu, Wenquan; Wang, Jingwei; Zhang, Mingzhi

2015-01-01

Soil hydraulic principles suggest that post-infiltration hypoxic conditions would be induced in the plant root-zone for drip-irrigated tomato production in small pots filled with natural soil. No previous study specifically examined the response of tomato plants (Solanum lycopersicum) at different growth stages to low soil aeration under these conditions. A 2 × 6 factorial experiment was conducted to quantify effects of no post-infiltration soil aeration versus aeration during 5 different periods (namely 27-33, 34-57, 58-85, 86-99, and 27-99 days after sowing), on growth and fruit quality of potted single tomato plants that were sub-surface trickle-irrigated every 2 days at 2 levels. Soil was aerated by injecting 2.5 liters of air into each pot through the drip tubing immediately after irrigation. Results showed that post-infiltration aeration, especially during the fruit setting (34-57 DAS) and enlargement (58-85 DAS) growth stages, can positively influence the yield, root dry weight and activity, and the nutritional (soluble solids and vitamin C content), taste (titratable acidity), and market quality (shape and firmness) of the tomato fruits. Interactions between irrigation level and post-infiltration aeration on some of these fruit quality parameters indicated a need for further study on the dynamic interplay of air and water in the root zone of the plants under the conditions of this experiment.

The intercropping partner affects arbuscular mycorrhizal fungi and Fusarium oxysporum f. sp. lycopersici interactions in tomato.

PubMed

Hage-Ahmed, Karin; Krammer, Johannes; Steinkellner, Siegrid

2013-10-01

Arbuscular mycorrhizal fungi (AMF) and their bioprotective aspects are of great interest in the context of sustainable agriculture. Combining the benefits of AMF with the utilisation of plant species diversity shows great promise for the management of plant diseases in environmentally compatible agriculture. In the present study, AMF were tested against Fusarium oxysporum f. sp. lycopersici with tomato intercropped with either leek, cucumber, basil, fennel or tomato itself. Arbuscular mycorrhizal (AM) root colonisation of tomato was clearly affected by its intercropping partners. Tomato intercropped with leek showed even a 20 % higher AM colonisation rate than tomato intercropped with tomato. Positive effects of AMF expressed as an increase of tomato biomass compared to the untreated control treatment could be observed in root as well as in shoot weights. A compensation of negative effects of F. oxysporum f. sp. lycopersici on tomato biomass by AMF was observed in the tomato/leek combination. The intercropping partners leek, cucumber, basil and tomato had no effect on F. oxysporum f. sp. lycopersici disease incidence or disease severity indicating no allelopathic suppression; however, tomato co-cultivated with tomato clearly showed a negative effect on one plant/pot with regard to biomass and disease severity of F. oxysporum f. sp. lycopersici. Nonetheless, bioprotective effects of AMF resulting in the decrease of F. oxysporum f. sp. lycopersici disease severity were evident in treatments with AMF and F. oxysporum f. sp. lycopersici co-inoculation. However, these bioprotective effects depended on the intercropping partner since these effects were only observed in the tomato/leek and tomato/basil combination and for the better developed plant of tomato/tomato. In conclusion, the effects of the intercropping partner on AMF colonisation of tomato are of great interest for crop plant communities and for the influences on each other. The outcome of the bioprotective

Role of Tomato Lipoxygenase D in Wound-Induced Jasmonate Biosynthesis and Plant Immunity to Insect Herbivores

PubMed Central

Li, Shuyu; Wang, Bao; Huang, Tingting; Du, Minmin; Sun, Jiaqiang; Kang, Le; Li, Chang-Bao; Li, Chuanyou

2013-01-01

In response to insect attack and mechanical wounding, plants activate the expression of genes involved in various defense-related processes. A fascinating feature of these inducible defenses is their occurrence both locally at the wounding site and systemically in undamaged leaves throughout the plant. Wound-inducible proteinase inhibitors (PIs) in tomato (Solanum lycopersicum) provide an attractive model to understand the signal transduction events leading from localized injury to the systemic expression of defense-related genes. Among the identified intercellular molecules in regulating systemic wound response of tomato are the peptide signal systemin and the oxylipin signal jasmonic acid (JA). The systemin/JA signaling pathway provides a unique opportunity to investigate, in a single experimental system, the mechanism by which peptide and oxylipin signals interact to coordinate plant systemic immunity. Here we describe the characterization of the tomato suppressor of prosystemin-mediated responses8 (spr8) mutant, which was isolated as a suppressor of (pro)systemin-mediated signaling. spr8 plants exhibit a series of JA-dependent immune deficiencies, including the inability to express wound-responsive genes, abnormal development of glandular trichomes, and severely compromised resistance to cotton bollworm (Helicoverpa armigera) and Botrytis cinerea. Map-based cloning studies demonstrate that the spr8 mutant phenotype results from a point mutation in the catalytic domain of TomLoxD, a chloroplast-localized lipoxygenase involved in JA biosynthesis. We present evidence that overexpression of TomLoxD leads to elevated wound-induced JA biosynthesis, increased expression of wound-responsive genes and, therefore, enhanced resistance to insect herbivory attack and necrotrophic pathogen infection. These results indicate that TomLoxD is involved in wound-induced JA biosynthesis and highlight the application potential of this gene for crop protection against insects and

Role of tomato lipoxygenase D in wound-induced jasmonate biosynthesis and plant immunity to insect herbivores.

PubMed

Yan, Liuhua; Zhai, Qingzhe; Wei, Jianing; Li, Shuyu; Wang, Bao; Huang, Tingting; Du, Minmin; Sun, Jiaqiang; Kang, Le; Li, Chang-Bao; Li, Chuanyou

2013-01-01

In response to insect attack and mechanical wounding, plants activate the expression of genes involved in various defense-related processes. A fascinating feature of these inducible defenses is their occurrence both locally at the wounding site and systemically in undamaged leaves throughout the plant. Wound-inducible proteinase inhibitors (PIs) in tomato (Solanum lycopersicum) provide an attractive model to understand the signal transduction events leading from localized injury to the systemic expression of defense-related genes. Among the identified intercellular molecules in regulating systemic wound response of tomato are the peptide signal systemin and the oxylipin signal jasmonic acid (JA). The systemin/JA signaling pathway provides a unique opportunity to investigate, in a single experimental system, the mechanism by which peptide and oxylipin signals interact to coordinate plant systemic immunity. Here we describe the characterization of the tomato suppressor of prosystemin-mediated responses8 (spr8) mutant, which was isolated as a suppressor of (pro)systemin-mediated signaling. spr8 plants exhibit a series of JA-dependent immune deficiencies, including the inability to express wound-responsive genes, abnormal development of glandular trichomes, and severely compromised resistance to cotton bollworm (Helicoverpa armigera) and Botrytis cinerea. Map-based cloning studies demonstrate that the spr8 mutant phenotype results from a point mutation in the catalytic domain of TomLoxD, a chloroplast-localized lipoxygenase involved in JA biosynthesis. We present evidence that overexpression of TomLoxD leads to elevated wound-induced JA biosynthesis, increased expression of wound-responsive genes and, therefore, enhanced resistance to insect herbivory attack and necrotrophic pathogen infection. These results indicate that TomLoxD is involved in wound-induced JA biosynthesis and highlight the application potential of this gene for crop protection against insects and

Inoculation of tomato plants with rhizobacteria enhances the performance of the phloem-feeding insect Bemisia tabaci

PubMed Central

Shavit, Roee; Ofek-Lalzar, Maya; Burdman, Saul; Morin, Shai

2013-01-01

In their natural environment, plants experience multiple biotic interactions and respond to this complexity in an integrated manner. Therefore, plant responses to herbivory are flexible and depend on the context and complexity in which they occur. For example, plant growth promoting rhizobacteria (PGPR) can enhance plant growth and induce resistance against microbial pathogens and herbivorous insects by a phenomenon termed induced systemic resistance (ISR). In the present study, we investigated the effect of tomato (Solanum lycopersicum) pre-inoculation with the PGPR Pseudomonas fluorescens WCS417r, on the performance of the generalist phloem-feeding insect Bemisia tabaci. Based on the ability of P. fluorescens WCS417r to prime for ISR against generalists chewing insects and necrotrophic pathogens, we hypothesized that pre-inoculated plants will strongly resist B. tabaci infestation. In contrast, we discovered that the pre-inoculation treatment increased the tomato plant suitability for B. tabaci which was emphasized both by faster developmental rate and higher survivability of nymph stages on pre-inoculated plants. Our molecular and chemical analyses suggested that the phenomenon is likely to be related to: (I) the ability of the bacteria to reduce the activity of the plant induced defense systems; (II) a possible manipulation by P. fluorescens of the plant quality (in terms of suitability for B. tabaci) through an indirect effect on the rhizosphere bacterial community. The contribution of our study to the pattern proposed for other belowground rhizobacteria and mycorrhizal fungi and aboveground generalist phloem-feeders is discussed. PMID:23964283

Hexanoic acid protects tomato plants against Botrytis cinerea by priming defence responses and reducing oxidative stress.

PubMed

Finiti, Ivan; de la O Leyva, María; Vicedo, Begonya; Gómez-Pastor, Rocío; López-Cruz, Jaime; García-Agustín, Pilar; Real, Maria Dolores; González-Bosch, Carmen

2014-08-01

Treatment with the resistance priming inducer hexanoic acid (Hx) protects tomato plants from Botrytis cinerea by activating defence responses. To investigate the molecular mechanisms underlying hexanoic acid-induced resistance (Hx-IR), we compared the expression profiles of three different conditions: Botrytis-infected plants (Inf), Hx-treated plants (Hx) and Hx-treated + infected plants (Hx+Inf). The microarray analysis at 24 h post-inoculation showed that Hx and Hx+Inf plants exhibited the differential expression and priming of many Botrytis-induced genes. Interestingly, we found that the activation by Hx of other genes was not altered by the fungus at this time point. These genes may be considered to be specific targets of the Hx priming effect and may help to elucidate its mechanisms of action. It is noteworthy that, in Hx and Hx+Inf plants, there was up-regulation of proteinase inhibitor genes, DNA-binding factors, enzymes involved in plant hormone signalling and synthesis, and, remarkably, the genes involved in oxidative stress. Given the relevance of the oxidative burst occurring in plant-pathogen interactions, the effect of Hx on this process was studied in depth. We showed by specific staining that reactive oxygen species (ROS) accumulation in Hx+Inf plants was reduced and more restricted around infection sites. In addition, these plants showed higher ratios of reduced to oxidized glutathione and ascorbate, and normal levels of antioxidant activities. The results obtained indicate that Hx protects tomato plants from B. cinerea by regulating and priming Botrytis-specific and non-specific genes, preventing the harmful effects of oxidative stress produced by infection. © 2013 BSPP AND JOHN WILEY & SONS LTD.

Purification and characterization of recombinant supersweet protein thaumatin II from tomato fruit.

PubMed

Firsov, Aleksey; Shaloiko, Lyubov; Kozlov, Oleg; Vinokurov, Leonid; Vainstein, Alexander; Dolgov, Sergey

2016-07-01

Thaumatin, a supersweet protein from the African plant katemfe (Thaumatococcus daniellii Benth.), is a promising zero-calorie sweetener for use in the food and pharmaceutical industries. Due to limited natural sources of thaumatin, its production using transgenic plants is an advantageous alternative. We report a simple protocol for purification of recombinant thaumatin II from transgenic tomato. Thaumatin was extracted from ripe tomato fruit in a low-salt buffer and purified on an SP-Sephacryl column. Recombinant thaumatin yield averaged 50 mg/kg fresh fruit. MALDI-MS analysis showed correct processing of thaumatin in tomato plants. The recombinant thaumatin was indistinguishable from the native protein in a taste test. The purified tomato-derived thaumatin had an intrinsic sweetness with a threshold value in taste tests of around 50 nM. These results demonstrate the potential of an expression system based on transgenic tomato plants for production of recombinant thaumatin for the food and pharmaceutical industries. Copyright © 2016 Elsevier Inc. All rights reserved.

Evaluation of diel patterns of relative changes in cell turgor of tomato plants using leaf patch clamp pressure probes.

PubMed

Lee, Kang M; Driever, Steven M; Heuvelink, Ep; Rüger, Simon; Zimmermann, Ulrich; de Gelder, Arie; Marcelis, Leo F M

2012-12-01

Relative changes in cell turgor of leaves of well-watered tomato plants were evaluated using the leaf patch clamp pressure probe (LPCP) under dynamic greenhouse climate conditions. LPCP changes, a measure for relative changes in cell turgor, were monitored at three different heights of transpiring and non-transpiring leaves of tomato plants on sunny and cloudy days simultaneously with whole plant water uptake. Clear diel patterns were observed for relative changes of cell turgor of both transpiring and non-transpiring leaves, which were stronger on sunny days than on cloudy days. A clear effect of canopy height was also observed. Non-transpiring leaves showed relative changes in cell turgor that closely followed plant water uptake throughout the day. However, in the afternoon the relative changes of cell turgor of the transpiring leaves displayed a delayed response in comparison to plant water uptake. Subsequent recovery of cell turgor loss of transpiring leaves during the following night appeared insufficient, as the pre-dawn turgescent state similar to the previous night was not attained. Copyright © Physiologia Plantarum 2012.

The induction of tomato leucine aminopeptidase genes (LapA) after Pseudomonas syringae pv. tomato infection is primarily a wound response triggered by coronatine.

PubMed

Pautot, V; Holzer, F M; Chaufaux, J; Walling, L L

2001-02-01

Tomato plants constitutively express a neutral leucine aminopeptidase (LAP-N) and an acidic LAP (LAP-A) during floral development and in leaves in response to insect infestation, wounding, and Pseudomonas syringae pv. tomato infection. To assess the physiological roles of LAP-A, a LapA-antisense construct (35S:asLapA1) was introduced into tomato. The 35S:asLapA1 plants had greatly reduced or showed undetectable levels of LAP-A and LAP-N proteins in healthy and wounded leaves and during floral development. Despite the loss of these aminopeptidases, no global changes in protein profiles were noted. The 35S:asLapA1 plants also exhibited no significant alteration in floral development and did not impact the growth and development of Manduca sexta and P. syringae pv. tomato growth rates during compatible or incompatible infections. To investigate the mechanism underlying the strong induction of LapA upon P. syringae pv. tomato infection, LapA expression was monitored after infection with coronatine-producing and -deficient P. syringae pv. tomato strains. LapA RNA and activity were detected only with the coronatine-producing P. syringae pv. tomato strain. Coronatine treatment of excised shoots caused increases in RNAs for jasmonic acid (JA)-regulated wound-response genes (LapA and pin2) but did not influence expression of a JA-regulated pathogenesis-related protein gene (PR-1). These results indicated that coronatine mimicked the wound response but was insufficient to activate JA-regulated PR genes.

Early anther ablation triggers parthenocarpic fruit development in tomato.

PubMed

Medina, Mónica; Roque, Edelín; Pineda, Benito; Cañas, Luis; Rodriguez-Concepción, Manuel; Beltrán, José Pío; Gómez-Mena, Concepción

2013-08-01

Fruit set and fruit development in tomato is largely affected by changes in environmental conditions, therefore autonomous fruit set independent of fertilization is a highly desirable trait in tomato. Here, we report the production and characterization of male-sterile transgenic plants that produce parthenocarpic fruits in two tomato cultivars (Micro-Tom and Moneymaker). We generated male-sterility using the cytotoxic gene barnase targeted to the anthers with the PsEND1 anther-specific promoter. The ovaries of these plants grew in the absence of fertilization producing seedless, parthenocarpic fruits. Early anther ablation is essential to trigger the developing of the transgenic ovaries into fruits, in the absence of the signals usually generated during pollination and fertilization. Ovaries are fully functional and can be manually pollinated to obtain seeds. The transgenic plants obtained in the commercial cultivar Moneymaker show that the parthenocarpic development of the fruit does not have negative consequences in fruit quality. Throughout metabolomic analyses of the tomato fruits, we have identified two elite lines which showed increased levels of several health promoting metabolites and volatile compounds. Thus, early anther ablation can be considered a useful tool to promote fruit set and to obtain seedless and good quality fruits in tomato plants. These plants are also useful parental lines to be used in hybrid breeding approaches. © 2013 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

[Effectiveness of aqueous extracts of aromatic and medicinal plants against tomato grey mould in Morocco].

PubMed

Kasmi, Manal; Aourach, Mohammed; El Boukari, Mohammed; Barrijal, Said; Essalmani, Haiat

2017-08-01

Grey mould is a major disease threatening the Moroccan tomato; this disease is often controlled by fungicides. However, the latter are a real danger to human health and environment. Thus, this study is part of the research of harmless alternatives such extracts of aromatic and medicinal plants (Lavandula officinalis, Thymus vulgaris, Cymbopogon citratus, and Melissa officinalis). In this study, the extracts of four medicinal and aromatic plants were tested for their antifungal potency in vitro and in vivo in order to select the most effective. The results show that, in vitro, the Lavandula officinalis, Thymus vulgaris and Cymbopogon citratus aqueous extracts all possess significant antifungal activity, whereas Melissa officinalis shows the least effective. Also in vivo only the aqueous extract of Cymbopogon citratus proves most effective against B. cinerea on tomato fruit. The test of the plants confirms that aqueous extracts of Cymbopogon citratus and Thymus vulgaris are most effective, while the aqueous extracts of Melissa officinalis and Lavandula officinalis always seem to be the least effective. Therefore, the aqueous extracts of Cymbopogon citratus and Thymus vulgaris are the most envisaged for the biological control of grey mould. Copyright © 2017 Académie des sciences. Published by Elsevier Masson SAS. All rights reserved.

A bench-scale, cost effective and simple method to elicit Lycopersicon esculentum cv. PKM1 (tomato) plants against Cucumber mosaic virus attack using ozone-mediated inactivated Cucumber mosaic virus inoculum.

PubMed

Sudhakar, N; Nagendra-Prasad, D; Mohan, N; Murugesan, K

2007-12-01

Studies were undertaken to evaluate ozone for inactivation of Cucumber mosaic virus present in the inoculum and to stimulate Lycopersicon esculentum cv. PKM1 (tomato) plants against Cucumber mosaic virus infection by using the inactivated Cucumber mosaic virus inoculum. Application of a T(4) (0.4mg/l) concentration of ozone to the inoculum containing Cucumber mosaic virus resulted in complete inactivation of the virus. The inactivated viral inoculum was mixed with a penetrator (delivery agent), referred to as T(4) preparation, and it was evaluated for the development of systemic acquired resistance in the tomato plants. Application of a T(4) preparation 5 days before inoculation with the Cucumber mosaic virus protected tomato plants from the effects of Cucumber mosaic virus. Among the components of the inactivated virus tested, coat protein subunits and aggregates were responsible for the acquired resistance in tomato plants. In field trials, the results of enzyme-linked immunosorbent assay revealed that, Cucumber mosaic virus accumulation was significantly less for all the test plants (16%) sprayed with the T(4) preparation than untreated control plants (89.5%) at 28 days postinoculation (dpi). A remarkable increase in the activities of the total soluble phenolics (10-fold) and salicylic acid (16-fold) was detected 5 days after the treatment in foliar extracts of test plants relative to untreated control plants. The results showed that treatment of tomato plants with inactivated viral inoculum led to a significant enhancement of protection against Cucumber mosaic virus attack in a manner that mimics a real pathogen and induces systemic acquired resistance.

Effect of Post-Infiltration Soil Aeration at Different Growth Stages on Growth and Fruit Quality of Drip-Irrigated Potted Tomato Plants (Solanum lycopersicum)

PubMed Central

Li, Yuan; Jia, Zongxia; Niu, Wenquan; Wang, Jingwei; Zhang, Mingzhi

2015-01-01

Soil hydraulic principles suggest that post-infiltration hypoxic conditions would be induced in the plant root-zone for drip-irrigated tomato production in small pots filled with natural soil. No previous study specifically examined the response of tomato plants (Solanum lycopersicum) at different growth stages to low soil aeration under these conditions. A 2 × 6 factorial experiment was conducted to quantify effects of no post-infiltration soil aeration versus aeration during 5 different periods (namely 27–33, 34–57, 58–85, 86–99, and 27–99 days after sowing), on growth and fruit quality of potted single tomato plants that were sub-surface trickle-irrigated every 2 days at 2 levels. Soil was aerated by injecting 2.5 liters of air into each pot through the drip tubing immediately after irrigation. Results showed that post-infiltration aeration, especially during the fruit setting (34–57 DAS) and enlargement (58–85 DAS) growth stages, can positively influence the yield, root dry weight and activity, and the nutritional (soluble solids and vitamin C content), taste (titratable acidity), and market quality (shape and firmness) of the tomato fruits. Interactions between irrigation level and post-infiltration aeration on some of these fruit quality parameters indicated a need for further study on the dynamic interplay of air and water in the root zone of the plants under the conditions of this experiment. PMID:26630675

Molecular characterization of plant growth promoting rhizobacteria that enhance peroxidase and phenylalanine ammonia-lyase activities in chile (Capsicum annuum L.) and tomato (Lycopersicon esculentum Mill.).

PubMed

Sharma, Alok; Pathak, Ashutosh; Sahgal, Manvika; Meyer, Jean-Marie; Wray, Victor; Johri, Bhavdish N

2007-11-01

Pythium and Phytophthora species are associated with damping-off diseases in vegetable nurseries and reduce seedling stand and yield. In this study, bacterial isolates were selected on the basis of in vitro antagonism potential to inhibit mycelial growth of damping-off pathogens along with plant growth properties for field assessment in wet and winter seasons. We demonstrate efficacy of bacterial isolates to protect chile and tomato plants under natural vegetable nursery and artificially created pathogen-infested (Pythium and Phytophthora spp.) nursery conditions. After 21 days of sowing, chile and tomato plants were harvested and analysed for peroxidase and phenylalanine ammonia-lyase activities. Pseudomonas sp. strains FQP PB-3, FQA PB-3 and GRP(3 )were most effective in increasing shoot length (P > 0.05%) in both artificial and natural field sites. For example, Pseudomonas sp. FQA PB-3 treatment increased shoot length by 40% in the artificial Pythium 4746 infested nursery site in chile plants in the wet season. The bacterial treatments significantly increased the activity of peroxidase and phenylalanine ammonia-lyase in chile and tomato plant tissues, which are well known as indicators of an active lignification process. Thus, we conclude that treatment with potential bacterial plant growth promoting agents help plants against pathogen invasion by modulating plant peroxidase and phenylalanine ammonia-lyase activities.

Tomato PYR/PYL/RCAR abscisic acid receptors show high expression in root, differential sensitivity to the abscisic acid agonist quinabactin, and the capability to enhance plant drought resistance.

PubMed

González-Guzmán, Miguel; Rodríguez, Lesia; Lorenzo-Orts, Laura; Pons, Clara; Sarrión-Perdigones, Alejandro; Fernández, Maria A; Peirats-Llobet, Marta; Forment, Javier; Moreno-Alvero, Maria; Cutler, Sean R; Albert, Armando; Granell, Antonio; Rodríguez, Pedro L

2014-08-01

Abscisic acid (ABA) plays a crucial role in the plant's response to both biotic and abiotic stress. Sustainable production of food faces several key challenges, particularly the generation of new varieties with improved water use efficiency and drought tolerance. Different studies have shown the potential applications of Arabidopsis PYR/PYL/RCAR ABA receptors to enhance plant drought resistance. Consequently the functional characterization of orthologous genes in crops holds promise for agriculture. The full set of tomato (Solanum lycopersicum) PYR/PYL/RCAR ABA receptors have been identified here. From the 15 putative tomato ABA receptors, 14 of them could be grouped in three subfamilies that correlated well with corresponding Arabidopsis subfamilies. High levels of expression of PYR/PYL/RCAR genes was found in tomato root, and some genes showed predominant expression in leaf and fruit tissues. Functional characterization of tomato receptors was performed through interaction assays with Arabidopsis and tomato clade A protein phosphatase type 2Cs (PP2Cs) as well as phosphatase inhibition studies. Tomato receptors were able to inhibit the activity of clade A PP2Cs differentially in an ABA-dependent manner, and at least three receptors were sensitive to the ABA agonist quinabactin, which inhibited tomato seed germination. Indeed, the chemical activation of ABA signalling induced by quinabactin was able to activate stress-responsive genes. Both dimeric and monomeric tomato receptors were functional in Arabidopsis plant cells, but only overexpression of monomeric-type receptors conferred enhanced drought resistance. In summary, gene expression analyses, and chemical and transgenic approaches revealed distinct properties of tomato PYR/PYL/RCAR ABA receptors that might have biotechnological implications. © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology.

The Tomato Terpene Synthase Gene Family1[W][OA

PubMed Central

Falara, Vasiliki; Akhtar, Tariq A.; Nguyen, Thuong T.H.; Spyropoulou, Eleni A.; Bleeker, Petra M.; Schauvinhold, Ines; Matsuba, Yuki; Bonini, Megan E.; Schilmiller, Anthony L.; Last, Robert L.; Schuurink, Robert C.; Pichersky, Eran

2011-01-01

Compounds of the terpenoid class play numerous roles in the interactions of plants with their environment, such as attracting pollinators and defending the plant against pests. We show here that the genome of cultivated tomato (Solanum lycopersicum) contains 44 terpene synthase (TPS) genes, including 29 that are functional or potentially functional. Of these 29 TPS genes, 26 were expressed in at least some organs or tissues of the plant. The enzymatic functions of eight of the TPS proteins were previously reported, and here we report the specific in vitro catalytic activity of 10 additional tomato terpene synthases. Many of the tomato TPS genes are found in clusters, notably on chromosomes 1, 2, 6, 8, and 10. All TPS family clades previously identified in angiosperms are also present in tomato. The largest clade of functional TPS genes found in tomato, with 12 members, is the TPS-a clade, and it appears to encode only sesquiterpene synthases, one of which is localized to the mitochondria, while the rest are likely cytosolic. A few additional sesquiterpene synthases are encoded by TPS-b clade genes. Some of the tomato sesquiterpene synthases use z,z-farnesyl diphosphate in vitro as well, or more efficiently than, the e,e-farnesyl diphosphate substrate. Genes encoding monoterpene synthases are also prevalent, and they fall into three clades: TPS-b, TPS-g, and TPS-e/f. With the exception of two enzymes involved in the synthesis of ent-kaurene, the precursor of gibberellins, no other tomato TPS genes could be demonstrated to encode diterpene synthases so far. PMID:21813655

Trichoderma asperellum strain T34 controls Fusarium wilt disease in tomato plants in soilless culture through competition for iron.

PubMed

Segarra, Guillem; Casanova, Eva; Avilés, Manuel; Trillas, Isabel

2010-01-01

Trichoderma asperellum strain T34 has been reported to control the disease caused by Fusarium oxysporum f.sp. lycopersici (Fol) on tomato plants. To study the importance of iron concentration in the growth media for the activity and competitiveness of T34 and the pathogen, we tested four iron concentrations in the nutrient solution [1, 10, 100, and 1000 microM provided as EDTA/Fe(III)] in a biological control experiment with T34 and Fol in tomato plants. The reduction of the Fusarium-infected shoot by T34 was only significant at 10 microM Fe. We hypothesized that Fe competition is one of the key factors in the biocontrol activity exerted by T34 against Fol, as an increase in Fe concentration over 10 microM would lead to the suppression of T34 siderophore synthesis and thus inhibition of Fe competition with Fol. T34 significantly reduced the populations of Fol at all the doses of Fe assayed. In contrast, Fol enhanced the populations of T34 at 1 and 10 microM Fe. Nevertheless, several plant physiological parameters like net CO(2) assimilation (A), stomatal conductance (g(s)), relative quantum efficiency of PSII (Phi(PSII)), and efficiency of excitation energy capture by open PSII reactive centers (Fv'/Fm') demonstrated the protection against Fol damage by treatment with T34 at 100 microM Fe. The first physiological parameter affected by the disease progression was g(s). Plant dry weight was decreased by Fe toxicity at 100 and 1,000 microM. T34-treated plants had significantly greater heights and dry weights than control plants at 1,000 microM Fe, even though T34 did not reduce the Fe content in leaves or stems. Furthermore, T34 enhanced plant height even at the optimal Fe concentration (10 microM) compared to control plants. In conclusion, T. asperellum strain T34 protected tomato plants from both biotic (Fusarium wilt disease) and abiotic stress [Fe(III) toxic effects].

Suppressive Potential of Paenibacillus Strains Isolated from the Tomato Phyllosphere against Fusarium Crown and Root Rot of Tomato

PubMed Central

Sato, Ikuo; Yoshida, Shigenobu; Iwamoto, Yutaka; Aino, Masataka; Hyakumachi, Mitsuro; Shimizu, Masafumi; Takahashi, Hideki; Ando, Sugihiro; Tsushima, Seiya

2014-01-01

The suppressive potentials of Bacillus and Paenibacillus strains isolated from the tomato phyllosphere were investigated to obtain new biocontrol candidates against Fusarium crown and root rot of tomato. The suppressive activities of 20 bacterial strains belonging to these genera were examined using seedlings and potted tomato plants, and two Paenibacillus strains (12HD2 and 42NP7) were selected as biocontrol candidates against the disease. These two strains suppressed the disease in the field experiment. Scanning electron microscopy revealed that the treated bacterial cells colonized the root surface, and when the roots of the seedlings were treated with strain 42NP7 cells, the cell population was maintained on the roots for at least for 4 weeks. Although the bacterial strains had no direct antifungal activity against the causal pathogen in vitro, an increase was observed in the antifungal activities of acetone extracts from tomato roots treated with the cells of both bacterial strains. Furthermore, RT-PCR analysis verified that the expression of defense-related genes was induced in both the roots and leaves of seedlings treated with the bacterial cells. Thus, the root-colonized cells of the two Paenibacillus strains were considered to induce resistance in tomato plants, which resulted in the suppression of the disease. PMID:24920171

Ectopic expression of ORANGE promotes carotenoid accumulation and fruit development in tomato.

PubMed

Yazdani, Mohammad; Sun, Zhaoxia; Yuan, Hui; Zeng, Shaohua; Thannhauser, Theodore W; Vrebalov, Julia; Ma, Qiyue; Xu, Yimin; Fei, Zhangjun; Van Eck, Joyce; Tian, Shiping; Tadmor, Yaakov; Giovannoni, James J; Li, Li

2018-05-05

Carotenoids are critically important to plants and humans. The ORANGE (OR) gene is a key regulator for carotenoid accumulation, but its physiological roles in crops remain elusive. In this study, we generated transgenic tomato ectopically overexpressing the Arabidopsis wild-type OR (AtOR WT ) and a 'golden SNP'-containing OR (AtOR H is ). We found that AtOR H is initiated chromoplast formation in very young fruit and stimulated carotenoid accumulation at all fruit developmental stages, uncoupled from other ripening activities. The elevated levels of carotenoids in the AtOR lines were distributed in the same subplastidial fractions as in wild-type tomato, indicating an adaptive response of plastids to sequester the increased carotenoids. Microscopic analysis revealed that the plastid sizes were increased in both AtOR WT and AtOR H is lines at early fruit developmental stages. Moreover, AtOR overexpression promoted early flowering, fruit set and seed production. Ethylene production and the expression of ripening-associated genes were also significantly increased in the AtOR transgenic fruit at ripening stages. RNA-Seq transcriptomic profiling highlighted the primary effects of OR overexpression on the genes in the processes related to RNA, protein and signalling in tomato fruit. Taken together, these results expand our understanding of OR in mediating carotenoid accumulation in plants and suggest additional roles of OR in affecting plastid size as well as flower and fruit development, thus making OR a target gene not only for nutritional biofortification of agricultural products but also for alteration of horticultural traits. © 2018 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

NO3- , PO43- and SO42- deprivation reduced LKT1-mediated low-affinity K+ uptake and SKOR-mediated K+ translocation in tomato and Arabidopsis plants.

PubMed

Ródenas, Reyes; García-Legaz, Manuel Francisco; López-Gómez, Elvira; Martínez, Vicente; Rubio, Francisco; Ángeles Botella, M

2017-08-01

Regulation of essential macronutrients acquisition by plants in response to their availability is a key process for plant adaptation to changing environments. Here we show in tomato and Arabidopsis plants that when they are subjected to NO 3 - , PO 4 3 - and SO 4 2 - deprivation, low-affinity K + uptake and K + translocation to the shoot are reduced. In parallel, these nutritional deficiencies produce reductions in the messenger levels of the genes encoding the main systems for low-affinity K + uptake and K + translocation, i.e. AKT1 and SKOR in Arabidopsis and LKT1 and the tomato homolog of SKOR, SlSKOR in tomato, respectively. The results suggest that the shortage of one nutrient produces a general downregulation of the acquisition of other nutrients. In the case of K + nutrient, one of the mechanisms for such a response resides in the transcriptional repression of the genes encoding the systems for K + uptake and translocation. © 2017 Scandinavian Plant Physiology Society.

Signal transduction in the wound response of tomato plants.

PubMed Central

Bowles, D

1998-01-01

The wound response of tomato plants has been extensively studied, and provides a useful model to understand signal transduction events leading from injury to marker gene expression. The principal markers that have been used in these studies are genes encoding proteinase inhibitor (pin) proteins. Activation of pin genes occurs in the wounded leaf and in distant unwounded leaves of the plant. This paper reviews current understanding of signalling pathways in the wounded leaf, and in the systemically responding unwounded leaves. First, the nature of known elicitors and their potential roles in planta are discussed, in particular, oligogalacturonides, jasmonates and the peptide signal, systemin. Inhibitors of wound-induced proteinase inhibitor (pin) expression are also reviewed, with particular reference to phenolics, sulphydryl reagents and fusicoccin. In each section, results obtained from the bioassay are considered within the wider context of data from mutants and from transgenic plants with altered levels of putative signalling components. Following this introduction, current models for pin gene regulation are described and discussed, together with a summary for the involvement of phosphorylation-dephosphorylation in wound signalling. Finally, a new model for wound-induced pin gene expression is presented, arising from recent data from the author's laboratory. PMID:9800210

Melatonin mediates selenium-induced tolerance to cadmium stress in tomato plants.

PubMed

Li, Meng-Qi; Hasan, Md Kamrul; Li, Cai-Xia; Ahammed, Golam Jalal; Xia, Xiao-Jian; Shi, Kai; Zhou, Yan-Hong; Reiter, Russel J; Yu, Jing-Quan; Xu, Ming-Xing; Zhou, Jie

2016-10-01

Both selenium (Se) and melatonin reduce cadmium (Cd) uptake and mitigate Cd toxicity in plants. However, the relationship between Se and melatonin in Cd detoxification remains unclear. In this study, we investigated the influence of three forms of Se (selenocysteine, sodium selenite, and sodium selenate) on the biosynthesis of melatonin and the tolerance against Cd in tomato plants. Pretreatment with different forms of Se significantly induced the biosynthesis of melatonin and its precursors (tryptophan, tryptamine, and serotonin); selenocysteine had the most marked effect on melatonin biosynthesis. Furthermore, Se and melatonin supplements significantly increased plant Cd tolerance as evidenced by decreased growth inhibition, photoinhibition, and electrolyte leakage (EL). Se-induced Cd tolerance was compromised in melatonin-deficient plants following tryptophan decarboxylase (TDC) gene silencing. Se treatment increased the levels of glutathione (GSH) and phytochelatins (PCs), as well as the expression of GSH and PC biosynthetic genes in nonsilenced plants, but the effects of Se were compromised in TDC-silenced plants under Cd stress. In addition, Se and melatonin supplements reduced Cd content in leaves of nonsilenced plants, but Se-induced reduction in Cd content was compromised in leaves of TDC-silenced plants. Taken together, our results indicate that melatonin is involved in Se-induced Cd tolerance via the regulation of Cd detoxification. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Design of Tomato Drying System by Utilizing Brine Geothermal

NASA Astrophysics Data System (ADS)

Afuar, W.; Sibarani, B.; Abdurrahman, G.; Hendrarsakti, J.

2016-09-01

Cultivation of tomato plants in Indonesia has been started since 1961.Tomatoes generally will rot in three days if left on storage. Moreover, low quality tomatoes have cheaper price. After harvested, tomatoes need to be treated by drying process so it can last longer. Energy for drying tomatoes can be obtained by utilizing heat from geothermal brine. Purpose of this research is to design a tomato drying system by extracting heat of geothermal brine from separator with certain flow rate to heat up water by using a heat exchanger. Furthermore, this water will be used to heat up the surrounding air which is circulated by blower system to heat up the tomatoes chamber. Tomatoes drying process needs temperature range of 50-70°C to evaporate water content from 95.7% to 26%. After that treatment, the tomatoes are expected to have better durability. The objective of this study is to determine the quantity of hot brine which is needed for drying tomatoes and to design a drying system so that tomatoes can last longer.

Foliar extracts from transgenic tomato plants expressing the structural polyprotein, P1-2A, and protease, 3C, from foot-and-mouth disease virus elicit a protective response in guinea pigs.

PubMed

Pan, Li; Zhang, Yongguang; Wang, Yonglu; Wang, Baoqin; Wang, Wenxiu; Fang, Yuzhen; Jiang, Shoutian; Lv, Jianliang; Wang, Wei; Sun, Yuan; Xie, Qingge

2008-01-15

The expression of recombinant antigens in transgenic plants is increasingly used as an alternative method of producing experimental immunogens. In this report, we describe the production of transgenic tomato plants that express the structural polyprotein, P1-2A, and protease, 3C, from foot-and-mouth disease (FMDV). P1-2A3C was inserted into the plant binary vector, pBin438, and transformed into tomato plants using Agrobacterium tumefaciens strain, GV3101. The presence of P1-2A3C was confirmed by PCR, transcription was verified by RT-PCR, and recombinant protein expression was confirmed by sandwich-ELISA and Western blot analyses. Guinea pigs immunized intramuscularly with foliar extracts from P1-2A3C-transgenic tomato plants were found to develop a virus-specific antibody response against FMDV. Vaccinated guinea pigs were fully protected against a challenge infection, while guinea pigs injected with untransformed plant extracts failed to elicit an antibody response and were not protected against challenge. These results demonstrate that transgenic tomato plants expressing the FMDV structural polyprotein, P1-2A, and the protease, 3C, can be used as a source of recombinant antigen for vaccine production.

Bio-effectors from waste materials as growth promoters for tomato plants, an agronomic and metabolomic study

NASA Astrophysics Data System (ADS)

Abou Chehade, Lara; Chami, Ziad Al; De Pascali, Sandra; Cavoski, Ivana; Fanizzi, Francesco Paolo

2015-04-01

In organic farming, where nutrient management is constrained and sustainability is claimed, bio-effectors pave their way. Considering selected bio-effectors, this study integrates metabolomics to agronomy in depicting induced relevant phenomena. Extracts of three agro-industrial wastes (Lemon processing residues, Fennel processing residues and Brewer's spent grain) are being investigated as sources of bio-effectors for the third trial consequently. Corresponding individual and mixture aqueous extracts are assessed for their synergistic and/or single agronomic and qualitative performances on soil-grown tomato, compared to both a control and humic acid treatments. A metabolomic profiling of tomato fruits via the Proton Nuclear Magnetic Resonance (NMR) spectroscopy, as holistic indicator of fruit quality and extract-induced responses, complements crop productivity and organoleptic/nutritional qualitative analyses. Results are expected to show mainly an enhancement of the fruit qualitative traits, and to confirm partly the previous results of better crop productivity and metabolism enhancement. Waste-derived bio-effectors could be, accordingly, demonstrated as potential candidates of plant-enhancing substances. Keywords: bio-effectors, organic farming, agro-industrial wastes, nuclear magnetic resonance (NMR), tomato.

Multiple phytohormone signalling pathways modulate susceptibility of tomato plants to Alternaria alternata f. sp. lycopersici

PubMed Central

Jia, Chengguo; Zhang, Liping; Wang, Qiaomei

2013-01-01

Three phytohormone molecules – ethylene (ET), jasmonic acid (JA) and salicylic acid (SA) – play key roles in mediating disease response to necrotrophic fungal pathogens. This study investigated the roles of the ET, JA, and SA pathways as well as their crosstalk during the interaction between tomato (Solanum lycopersicum) plants and a necrotrophic fungal pathogen Alternaria alternata f. sp. lycopersici (AAL). Both the ET and JASMONIC ACID INSENSITIVE1 (JAI1) receptor-dependent JA signalling pathways are necessary for susceptibility, while SA response promotes resistance to AAL infection. In addition, the role of JA in susceptibility to AAL is partly dependent on ET biosynthesis and perception, while the SA pathway enhances resistance to AAL and antagonizes the ET response. Based on these results, it is proposed that ET, JA, and SA each on their own can influence the susceptibility of tomato to AAL. Furthermore, the functions of JA and SA in susceptibility to the pathogen are correlated with the enhanced or decreased action of ET, respectively. This study has revealed the functional relationship among the three key hormone pathways in tomato defence against AAL. PMID:23264518

Tomato response to legume cover crop and nitrogen: differing enhancement patterns of fruit yield, photosynthesis and gene expression

USDA-ARS?s Scientific Manuscript database

Tomatoes responded to soil and residue from a hairy vetch cover crop differently on many levels than tomato response to inorganic nitrogen. Tomato fruit production, plant biomass parameters, and photosynthesis were higher in plants grown in vetch than bare soil. Tomato growth and photosynthesis metr...

High invertase activity in tomato reproductive organs correlates with enhanced sucrose import into, and heat tolerance of, young fruit.

PubMed

Li, Zhimiao; Palmer, William M; Martin, Antony P; Wang, Rongqing; Rainsford, Frederick; Jin, Ye; Patrick, John W; Yang, Yuejian; Ruan, Yong-Ling

2012-02-01

Heat stress can cause severe crop yield losses by impairing reproductive development. However, the underlying mechanisms are poorly understood. We examined patterns of carbon allocation and activities of sucrose cleavage enzymes in heat-tolerant (HT) and -sensitive (HS) tomato (Solanum lycopersicum L.) lines subjected to normal (control) and heat stress temperatures. At the control temperature of 25/20 °C (day/night) the HT line exhibited higher cell wall invertase (CWIN) activity in flowers and young fruits and partitioned more sucrose to fruits but less to vegetative tissues as compared to the HS line, independent of leaf photosynthetic capacity. Upon 2-, 4-, or 24-h exposure to day or night temperatures of 5 °C or more above 25/20 °C, cell wall (CWIN) and vacuolar invertases (VIN), but not sucrose synthase (SuSy), activities in young fruit of the HT line were significantly higher than those of the HS line. The HT line had a higher level of transcript of a CWIN gene, Lin7, in 5-day fruit than the HS line under control and heat stress temperatures. Interestingly, heat induced transcription of an invertase inhibitor gene, INVINH1, but reduced its protein abundance. Transcript levels of LePLDa1, encoding phospholipase D, which degrades cell membranes, was less in the HT line than in the HS line after exposure to heat stress. The data indicate that high invertase activity of, and increased sucrose import into, young tomato fruit could contribute to their heat tolerance through increasing sink strength and sugar signalling activities, possibly regulating a programmed cell death pathway.

Analysis of gas exchange, stomatal behaviour and micronutrients uncovers dynamic response and adaptation of tomato plants to monochromatic light treatments.

PubMed

O'Carrigan, Andrew; Babla, Mohammad; Wang, Feifei; Liu, Xiaohui; Mak, Michelle; Thomas, Richard; Bellotti, Bill; Chen, Zhong-Hua

2014-09-01

Light spectrum affects the yield and quality of greenhouse tomato, especially over a prolonged period of monochromatic light treatments. Physiological and chemical analysis was employed to investigate the influence of light spectral (blue, green and red) changes on growth, photosynthesis, stomatal behaviour, leaf pigment, and micronutrient levels. We found that plants are less affected under blue light treatment, which was evident by the maintenance of higher A, gs, Tr, and stomatal parameters and significantly lower VPD and Tleaf as compared to those plants grown in green and red light treatments. Green and red light treatments led to significantly larger increase in the accumulation of Fe, B, Zn, and Cu than blue light. Moreover, guard cell length, width, and volume all showed highly significant positive correlations to gs, Tr and negative links to VPD. There was negative impact of monochromatic lights-induced accumulation of Mn, Cu, and Zn on photosynthesis, leaf pigments and plant growth. Furthermore, most of the light-induced significant changes of the physiological traits were partially recovered at the end of experiment. A high degree of morphological and physiological plasticity to blue, green and red light treatments suggested that tomato plants may have developed mechanisms to adapt to the light treatments. Thus, understanding the optimization of light spectrum for photosynthesis and growth is one of the key components for greenhouse tomato production. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Calcium partitioning and allocation and blossom-end rot development in tomato plants in response to whole-plant and fruit-specific abscisic acid treatments.

PubMed

Tonetto de Freitas, Sergio; McElrone, Andrew J; Shackel, Kenneth A; Mitcham, Elizabeth J

2014-01-01

The mechanisms regulating Ca(2+) partitioning and allocation in plants and fruit remain poorly understood. The objectives of this study were to determine Ca(2+) partitioning and allocation in tomato plants and fruit in response to whole-plant and fruit-specific abscisic acid (ABA) treatments, as well as to analyse the effect of changes in Ca(2+) partitioning and allocation on fruit susceptibility to the Ca(2+) deficiency disorder blossom-end rot (BER) under water stress conditions. Tomato plants of the cultivar Ace 55 (Vf) were grown in a greenhouse and exposed to low Ca(2+) conditions during fruit growth and development. Starting 1 day after pollination (DAP), the following treatments were initiated: (i) whole plants were sprayed weekly with deionized water (control) or (ii) with 500mg l(-1) ABA; or fruit on each plant were dipped weekly (iii) in deionized water (control) or (iv) in 500mg l(-1) ABA. At 15 DAP, BER was completely prevented by whole-plant or fruit-specific ABA treatments, whereas plants or fruit treated with water had 16-19% BER incidence. At 30 DAP, BER was prevented by the whole-plant ABA treatment, whereas fruit dipped in ABA had a 16% and water-treated plants or fruit had a 36-40% incidence of BER. The results showed that spraying the whole plant with ABA increases xylem sap flow and Ca(2+) movement into the fruit, resulting in higher fruit tissue and water-soluble apoplastic Ca(2+) concentrations that prevent BER development. Although fruit-specific ABA treatment had no effect on xylem sap flow rates or Ca(2+) movement into the fruit, it increased fruit tissue water-soluble apoplastic Ca(2+) concentrations and reduced fruit susceptibility to BER to a lesser extent.

Calcium partitioning and allocation and blossom-end rot development in tomato plants in response to whole-plant and fruit-specific abscisic acid treatments

PubMed Central

Tonetto de Freitas, Sergio

2014-01-01

The mechanisms regulating Ca2+ partitioning and allocation in plants and fruit remain poorly understood. The objectives of this study were to determine Ca2+ partitioning and allocation in tomato plants and fruit in response to whole-plant and fruit-specific abscisic acid (ABA) treatments, as well as to analyse the effect of changes in Ca2+ partitioning and allocation on fruit susceptibility to the Ca2+ deficiency disorder blossom-end rot (BER) under water stress conditions. Tomato plants of the cultivar Ace 55 (Vf) were grown in a greenhouse and exposed to low Ca2+ conditions during fruit growth and development. Starting 1 day after pollination (DAP), the following treatments were initiated: (i) whole plants were sprayed weekly with deionized water (control) or (ii) with 500mg l−1 ABA; or fruit on each plant were dipped weekly (iii) in deionized water (control) or (iv) in 500mg l−1 ABA. At 15 DAP, BER was completely prevented by whole-plant or fruit-specific ABA treatments, whereas plants or fruit treated with water had 16–19% BER incidence. At 30 DAP, BER was prevented by the whole-plant ABA treatment, whereas fruit dipped in ABA had a 16% and water-treated plants or fruit had a 36–40% incidence of BER. The results showed that spraying the whole plant with ABA increases xylem sap flow and Ca2+ movement into the fruit, resulting in higher fruit tissue and water-soluble apoplastic Ca2+ concentrations that prevent BER development. Although fruit-specific ABA treatment had no effect on xylem sap flow rates or Ca2+ movement into the fruit, it increased fruit tissue water-soluble apoplastic Ca2+ concentrations and reduced fruit susceptibility to BER to a lesser extent. PMID:24220654

Nitrogen Metabolism and Growth Enhancement in Tomato Plants Challenged with Trichoderma harzianum Expressing the Aspergillus nidulans Acetamidase amdS Gene

PubMed Central

Domínguez, Sara; Rubio, M. Belén; Cardoza, Rosa E.; Gutiérrez, Santiago; Nicolás, Carlos; Bettiol, Wagner; Hermosa, Rosa; Monte, Enrique

2016-01-01

Trichoderma is a fungal genus that includes species that are currently being used as biological control agents and/or as biofertilizers. In addition to the direct application of Trichoderma spp. as biocontrol agents in plant protection, recent studies have focused on the beneficial responses exerted on plants, stimulating the growth, activating the defenses, and/or improving nutrient uptake. The amdS gene, encoding an acetamidase of Aspergillus, has been used as a selectable marker for the transformation of filamentous fungi, including Trichoderma spp., but the physiological effects of the introduction of this gene into the genome of these microorganisms still remains unexplored. No evidence of amdS orthologous genes has been detected within the Trichoderma spp. genomes and the amdS heterologous expression in Trichoderma harzianum T34 did not affect the growth of this fungus in media lacking acetamide. However, it did confer the ability for the fungus to use this amide as a nitrogen source. Although a similar antagonistic behavior was observed for T34 and amdS transformants in dual cultures against Rhizoctonia solani, Botrytis cinerea, and Fusarium oxysporum, a significantly higher antifungal activity was detected in amdS transformants against F. oxysporum, compared to that of T34, in membrane assays on media lacking acetamide. In Trichoderma-tomato interaction assays, amdS transformants were able to promote plant growth to a greater extent than the wild-type T34, although compared with this strain the transformants showed similar capability to colonize tomato roots. Gene expression patterns from aerial parts of 3-week-old tomato plants treated with T34 and the amdS transformants have also been investigated using GeneChip Tomato Genome Arrays. The downregulation of defense genes and the upregulation of carbon and nitrogen metabolism genes observed in the microarrays were accompanied by (i) enhanced growth, (ii) increased carbon and nitrogen levels, and (iii) a

Nitrogen Metabolism and Growth Enhancement in Tomato Plants Challenged with Trichoderma harzianum Expressing the Aspergillus nidulans Acetamidase amdS Gene.

PubMed

Domínguez, Sara; Rubio, M Belén; Cardoza, Rosa E; Gutiérrez, Santiago; Nicolás, Carlos; Bettiol, Wagner; Hermosa, Rosa; Monte, Enrique

2016-01-01

Trichoderma is a fungal genus that includes species that are currently being used as biological control agents and/or as biofertilizers. In addition to the direct application of Trichoderma spp. as biocontrol agents in plant protection, recent studies have focused on the beneficial responses exerted on plants, stimulating the growth, activating the defenses, and/or improving nutrient uptake. The amdS gene, encoding an acetamidase of Aspergillus, has been used as a selectable marker for the transformation of filamentous fungi, including Trichoderma spp., but the physiological effects of the introduction of this gene into the genome of these microorganisms still remains unexplored. No evidence of amdS orthologous genes has been detected within the Trichoderma spp. genomes and the amdS heterologous expression in Trichoderma harzianum T34 did not affect the growth of this fungus in media lacking acetamide. However, it did confer the ability for the fungus to use this amide as a nitrogen source. Although a similar antagonistic behavior was observed for T34 and amdS transformants in dual cultures against Rhizoctonia solani, Botrytis cinerea, and Fusarium oxysporum, a significantly higher antifungal activity was detected in amdS transformants against F. oxysporum, compared to that of T34, in membrane assays on media lacking acetamide. In Trichoderma-tomato interaction assays, amdS transformants were able to promote plant growth to a greater extent than the wild-type T34, although compared with this strain the transformants showed similar capability to colonize tomato roots. Gene expression patterns from aerial parts of 3-week-old tomato plants treated with T34 and the amdS transformants have also been investigated using GeneChip Tomato Genome Arrays. The downregulation of defense genes and the upregulation of carbon and nitrogen metabolism genes observed in the microarrays were accompanied by (i) enhanced growth, (ii) increased carbon and nitrogen levels, and (iii) a

Tomato Spotted Wilt Virus Particle Morphogenesis in Plant Cells

PubMed Central

Kikkert, Marjolein; Van Lent, Jan; Storms, Marc; Bodegom, Pentcho; Kormelink, Richard; Goldbach, Rob

1999-01-01

A model for the maturation of tomato spotted wilt virus (TSWV) particles is proposed, mainly based on results with a protoplast infection system, in which the chronology of different maturation events could be determined. By using specific monoclonal and polyclonal antisera in immunofluorescence and electron microscopy, the site of TSWV particle morphogenesis was determined to be the Golgi system. The viral glycoproteins G1 and G2 accumulate in the Golgi prior to a process of wrapping, by which the viral nucleocapsids obtain a double membrane. In a later stage of the maturation, these doubly enveloped particles fuse to each other and to the endoplasmic reticulum to form singly enveloped particles clustered in membranes. Similarities and differences between the maturation of animal-infecting (bunya)viruses and plant-infecting tospoviruses are discussed. PMID:9971812

Genetic Diversity of Tomato Viroids in North America

USDA-ARS?s Scientific Manuscript database

The North American greenhouse tomato industry has expanded dramatically in the last couple of decades. Nearly 40% of fresh tomatoes in the U.S. supermarkets are now produced in greenhouses. The intense production practices and the protective plant growing environment resulted in a number of unique...

Characterization of two biologically distinct variants of Tomato spotted wilt virus

USDA-ARS?s Scientific Manuscript database

Significant economic losses result on a wide range of crops due to infection with Tomato spotted wilt virus (TSWV). In this study, two TSWV isolates, one from basil and a second from tomato, were established in a common plant host. Viral proteins were monitored over time, plant host ranges were comp...

Proteomic analysis of ripening tomato fruit infected by Botrytis cinerea.

PubMed

Shah, Punit; Powell, Ann L T; Orlando, Ron; Bergmann, Carl; Gutierrez-Sanchez, Gerardo

2012-04-06

Botrytis cinerea, a model necrotrophic fungal pathogen that causes gray mold as it infects different organs on more than 200 plant species, is a significant contributor to postharvest rot in fresh fruit and vegetables, including tomatoes. By describing host and pathogen proteomes simultaneously in infected tissues, the plant proteins that provide resistance and allow susceptibility and the pathogen proteins that promote colonization and facilitate quiescence can be identified. This study characterizes fruit and fungal proteins solubilized in the B. cinerea-tomato interaction using shotgun proteomics. Mature green, red ripe wild type and ripening inhibited (rin) mutant tomato fruit were infected with B. cinerea B05.10, and the fruit and fungal proteomes were identified concurrently 3 days postinfection. One hundred eighty-six tomato proteins were identified in common among red ripe and red ripe-equivalent ripening inhibited (rin) mutant tomato fruit infected by B. cinerea. However, the limited infections by B. cinerea of mature green wild type fruit resulted in 25 and 33% fewer defense-related tomato proteins than in red and rin fruit, respectively. In contrast, the ripening stage of genotype of the fruit infected did not affect the secreted proteomes of B. cinerea. The composition of the collected proteins populations and the putative functions of the identified proteins argue for their role in plant-pathogen interactions.

Differential Timing of Spider Mite-Induced Direct and Indirect Defenses in Tomato Plants1[w

PubMed Central

Kant, Merijn R.; Ament, Kai; Sabelis, Maurice W.; Haring, Michel A.; Schuurink, Robert C.

2004-01-01

Through a combined metabolomics and transcriptomics approach we analyzed the events that took place during the first 5 d of infesting intact tomato (Lycopersicon esculentum) plants with spider mites (Tetranychus urticae). Although the spider mites had caused little visible damage to the leaves after 1 d, they had already induced direct defense responses. For example, proteinase inhibitor activity had doubled and the transcription of genes involved in jasmonate-, salicylate-, and ethylene-regulated defenses had been activated. On day four, proteinase inhibitor activity and particularly transcript levels of salicylate-regulated genes were still maintained. In addition, genes involved in phospholipid metabolism were up-regulated on day one and those in the secondary metabolism on day four. Although transcriptional up-regulation of the enzymes involved in the biosynthesis of monoterpenes and diterpenes already occurred on day one, a significant increase in the emission of volatile terpenoids was delayed until day four. This increase in volatile production coincided with the increased olfactory preference of predatory mites (Phytoseiulus persimilis) for infested plants. Our results indicate that tomato activates its indirect defenses (volatile production) to complement the direct defense response against spider mites. PMID:15122016

Bacterial antagonists of fungal pathogens also control root-knot nematodes by induced systemic resistance of tomato plants.

PubMed

Adam, Mohamed; Heuer, Holger; Hallmann, Johannes

2014-01-01

The potential of bacterial antagonists of fungal pathogens to control the root-knot nematode Meloidogyne incognita was investigated under greenhouse conditions. Treatment of tomato seeds with several strains significantly reduced the numbers of galls and egg masses compared with the untreated control. Best performed Bacillus subtilis isolates Sb4-23, Mc5-Re2, and Mc2-Re2, which were further studied for their mode of action with regard to direct effects by bacterial metabolites or repellents, and plant mediated effects. Drenching of soil with culture supernatants significantly reduced the number of egg masses produced by M. incognita on tomato by up to 62% compared to the control without culture supernatant. Repellence of juveniles by the antagonists was shown in a linked twin-pot set-up, where a majority of juveniles penetrated roots on the side without inoculated antagonists. All tested biocontrol strains induced systemic resistance against M. incognita in tomato, as revealed in a split-root system where the bacteria and the nematodes were inoculated at spatially separated roots of the same plant. This reduced the production of egg masses by up to 51%, while inoculation of bacteria and nematodes in the same pot had only a minor additive effect on suppression of M. incognita compared to induced systemic resistance alone. Therefore, the plant mediated effect was the major reason for antagonism rather than direct mechanisms. In conclusion, the bacteria known for their antagonistic potential against fungal pathogens also suppressed M. incognita. Such "multi-purpose" bacteria might provide new options for control strategies, especially with respect to nematode-fungus disease complexes that cause synergistic yield losses.

The Effect of Spectral Quality on Daily Patterns of Gas Exchange, Biomass Gain, and Water-Use-Efficiency in Tomatoes and Lisianthus: An Assessment of Whole Plant Measurements.

PubMed

Lanoue, Jason; Leonardos, Evangelos D; Ma, Xiao; Grodzinski, Bernard

2017-01-01

Advancements in light-emitting diode (LED) technology have made them a viable alternative to current lighting systems for both sole and supplemental lighting requirements. Understanding how wavelength specific LED lighting can affect plants is thus an area of great interest. Much research is available on the wavelength specific responses of leaves from multiple crops when exposed to long-term wavelength specific lighting. However, leaf measurements do not always extrapolate linearly to the complexities which are found within a whole plant canopy, namely mutual shading and leaves of different ages. Taken together, both tomato ( Solanum lycopersicum ) leaves under short-term illumination and lisianthus ( Eustoma grandiflorum ) and tomato whole plant diurnal patterns of plants acclimated to specific lighting indicate wavelength specific responses of both H 2 O and CO 2 gas exchanges involved in the major growth parameters of a plant. Tomato leaves grown under a white light source indicated an increase in transpiration rate and internal CO 2 concentration and a subsequent decrease in water-use-efficiency (WUE) when exposed to a blue LED light source compared to a green LED light source. Interestingly, the maximum photosynthetic rate was observed to be similar. Using plants grown under wavelength specific supplemental lighting in a greenhouse, a decrease in whole plant WUE was seen in both crops under both red-blue (RB) and red-white (RW) LEDs when compared to a high pressure sodium (HPS) light. Whole plant WUE was decreased by 31% under the RB LED treatment for both crops compared to the HPS treatment. Tomato whole plant WUE was decreased by 25% and lisianthus whole plant WUE was decreased by 15% when compared to the HPS treatment when grown under RW LED. The understanding of the effects of wavelength specific lighting on both leaf and whole plant gas exchange has significant implications on basic academic research as well as commercial greenhouse production.

Subcellular Localization of Pseudomonas syringae pv. tomato Effector Proteins in Plants.

PubMed

Aung, Kyaw; Xin, Xiufang; Mecey, Christy; He, Sheng Yang

2017-01-01

Animal and plant pathogenic bacteria use type III secretion systems to translocate proteinaceous effectors to subvert innate immunity of their host organisms. Type III secretion/effector systems are a crucial pathogenicity factor in many bacterial pathogens of plants and animals. Pseudomonas syringae pv. tomato (Pst) DC3000 injects a total of 36 protein effectors that target a variety of host proteins. Studies of a subset of Pst DC3000 effectors demonstrated that bacterial effectors, once inside the host cell, are localized to different subcellular compartments, including plasma membrane, cytoplasm, mitochondria, chloroplast, and Trans-Golgi network, to carry out their virulence functions. Identifying the subcellular localization of bacterial effector proteins in host cells could provide substantial clues to understanding the molecular and cellular basis of the virulence activities of effector proteins. In this chapter, we present methods for transient or stable expression of bacterial effector proteins in tobacco and/or Arabidopsis thaliana for live cell imaging as well as confirming the subcellular localization in plants using fluorescent organelle markers or chemical treatment.

Biochar and flyash inoculated with plant growth promoting rhizobacteria act as potential biofertilizer for luxuriant growth and yield of tomato plant.

PubMed

Tripti; Kumar, Adarsh; Usmani, Zeba; Kumar, Vipin; Anshumali

2017-04-01

Overuse of agrochemical fertilizers alarmingly causes deterioration in soil health and soil-flora. Persistence of these agrochemicals exerts detrimental effects on environment, potentially inducing toxic effects on human health, thus pronouncing an urgent need for a safer substitute. The present study investigates the potential use of agricultural and industrial wastes as carrier materials, viz. biochar and flyash, respectively, for preparation of bioformulations (or biofertilizers) using two plant growth promoting rhizobacteria, Bacillus sp. strain A30 and Burkholderia sp. strain L2, and its effect on growth of Lycopersicon esculentum Mill. (tomato). The viability of strains was determined based on colony forming units (cfu) count of each bioformulation at an interval of 60 days for a period of 240 days. Seeds were coated with different carrier based bioformulations and pot experiment(s) were carried out to access its effects on plant growth parameters. Biochar based bioformulations showed higher cfu count and maximum viability for strain L2 (10 7  cfu g -1 ) at 240 days of storage. Maximum percentage of seed germination was also observed in biochar inoculated with strain L2. Significant (p < 0.05) increase in plant growth parameters (dry and fresh biomass, length, number of flowers) were ascertained from the pot experiment and amongst all bioformulations, biochar inoculated with strain L2 performed consistently thriving results for tomato yield. Furthermore, post-harvest study of this bioformulation treated soil improved physico-chemical properties and dehydrogenase activity as compared to pre-plantation soil status. Overall, we show that prepared biochar based bioformulation using Burkholderia sp. L2 as inoculum can tremendously enhance the productivity of tomato, soil fertility, and can also act as a sustainable substitute for chemical fertilizers. In addition, mixture of biochar and flyash inoculated with strain L2 also showed noteworthy results for the

A Robust Deep-Learning-Based Detector for Real-Time Tomato Plant Diseases and Pests Recognition.

PubMed

Fuentes, Alvaro; Yoon, Sook; Kim, Sang Cheol; Park, Dong Sun

2017-09-04

Plant Diseases and Pests are a major challenge in the agriculture sector. An accurate and a faster detection of diseases and pests in plants could help to develop an early treatment technique while substantially reducing economic losses. Recent developments in Deep Neural Networks have allowed researchers to drastically improve the accuracy of object detection and recognition systems. In this paper, we present a deep-learning-based approach to detect diseases and pests in tomato plants using images captured in-place by camera devices with various resolutions. Our goal is to find the more suitable deep-learning architecture for our task. Therefore, we consider three main families of detectors: Faster Region-based Convolutional Neural Network (Faster R-CNN), Region-based Fully Convolutional Network (R-FCN), and Single Shot Multibox Detector (SSD), which for the purpose of this work are called "deep learning meta-architectures". We combine each of these meta-architectures with "deep feature extractors" such as VGG net and Residual Network (ResNet). We demonstrate the performance of deep meta-architectures and feature extractors, and additionally propose a method for local and global class annotation and data augmentation to increase the accuracy and reduce the number of false positives during training. We train and test our systems end-to-end on our large Tomato Diseases and Pests Dataset, which contains challenging images with diseases and pests, including several inter- and extra-class variations, such as infection status and location in the plant. Experimental results show that our proposed system can effectively recognize nine different types of diseases and pests, with the ability to deal with complex scenarios from a plant's surrounding area.

Cyperus rotundus extract inhibits acetylcholinesterase activity from animal and plants as well as inhibits germination and seedling growth in wheat and tomato.

PubMed

Sharma, Rashmi; Gupta, Rajendra

2007-05-30

Cyperus rotundus (nutgrass) is the world's worst invasive weed through tubers. Its success in dominating natural habitats depends on its ability to prevent herbivory, and to kill or suppress other plants growing in its vicinity. The present study was done to investigate whether chemicals in nutgrass target neuronal and non-neuronal acetylcholinesterases to affect surrounding animals and plants respectively. Methanolic extract of tubers of nutgrass strongly inhibited activity of AChE from electric eel, wheat and tomato. It also inhibited seed germination and seedling growth in wheat and tomato. Our results suggest that inhibitor of AChE in nutgrass possibly acts as agent of plant's war against (a) herbivore animals, and (b) other plants trying to grow in the same habitat. An antiAChE from nutgrass has been purified by employing chromatography and crystallization. The structural determination of the purified inhibitor is in progress.

Genome-wide microarray analysis of tomato roots showed defined responses to iron deficiency

PubMed Central

2012-01-01

Background Plants react to iron deficiency stress adopting different kind of adaptive responses. Tomato, a Strategy I plant, improves iron uptake through acidification of rhizosphere, reduction of Fe3+ to Fe2+ and transport of Fe2+ into the cells. Large-scale transcriptional analyses of roots under iron deficiency are only available for a very limited number of plant species with particular emphasis for Arabidopsis thaliana. Regarding tomato, an interesting model species for Strategy I plants and an economically important crop, physiological responses to Fe-deficiency have been thoroughly described and molecular analyses have provided evidence for genes involved in iron uptake mechanisms and their regulation. However, no detailed transcriptome analysis has been described so far. Results A genome-wide transcriptional analysis, performed with a chip that allows to monitor the expression of more than 25,000 tomato transcripts, identified 97 differentially expressed transcripts by comparing roots of Fe-deficient and Fe-sufficient tomato plants. These transcripts are related to the physiological responses of tomato roots to the nutrient stress resulting in an improved iron uptake, including regulatory aspects, translocation, root morphological modification and adaptation in primary metabolic pathways, such as glycolysis and TCA cycle. Other genes play a role in flavonoid biosynthesis and hormonal metabolism. Conclusions The transcriptional characterization confirmed the presence of the previously described mechanisms to adapt to iron starvation in tomato, but also allowed to identify other genes potentially playing a role in this process, thus opening new research perspectives to improve the knowledge on the tomato root response to the nutrient deficiency. PMID:22433273

Transcriptomics of the interaction between the monopartite phloem-limited geminivirus tomato yellow leaf curl Sardinia virus and Solanum lycopersicum highlights a role for plant hormones, autophagy and plant immune system fine tuning during infection.

PubMed

Miozzi, Laura; Napoli, Chiara; Sardo, Luca; Accotto, Gian Paolo

2014-01-01

Tomato yellow leaf curl Sardinia virus (TYLCSV), a DNA virus belonging to the genus Begomovirus, causes severe losses in tomato crops. It infects only a limited number of cells in the vascular tissues, making difficult to detect changes in host gene expression linked to its presence. Here we present the first microarray study of transcriptional changes induced by the phloem-limited geminivirus TYLCSV infecting tomato, its natural host. The analysis was performed on the midrib of mature leaves, a material naturally enriched in vascular tissues. A total of 2206 genes were up-regulated and 1398 were down-regulated in infected plants, with an overrepresentation of genes involved in hormone metabolism and responses, nucleic acid metabolism, regulation of transcription, ubiquitin-proteasome pathway and autophagy among those up-regulated, and in primary and secondary metabolism, phosphorylation, transcription and methylation-dependent chromatin silencing among those down-regulated. Our analysis showed a series of responses, such as the induction of GA- and ABA-responsive genes, the activation of the autophagic process and the fine tuning of the plant immune system, observed only in TYLCSV-tomato compatible interaction so far. On the other hand, comparisons with transcriptional changes observed in other geminivirus-plant interactions highlighted common host responses consisting in the deregulation of biotic stress responsive genes, key enzymes in the ethylene biosynthesis and methylation cycle, components of the ubiquitin proteasome system and DNA polymerases II. The involvement of conserved miRNAs and of solanaceous- and tomato-specific miRNAs in geminivirus infection, investigated by integrating differential gene expression data with miRNA targeting data, is discussed.

Surface-enhanced Raman spectroscopy of genomic DNA from in vitro grown tomato (Lycopersicon esculentum Mill.) cultivars before and after plant cryopreservation

NASA Astrophysics Data System (ADS)

Muntean, Cristina M.; Leopold, Nicolae; Tripon, Carmen; Coste, Ana; Halmagyi, Adela

2015-06-01

In this work the surface-enhanced Raman scattering (SERS) spectra of five genomic DNAs from non-cryopreserved control tomato plants (Lycopersicon esculentum Mill. cultivars Siriana, Darsirius, Kristin, Pontica and Capriciu) respectively, have been analyzed in the wavenumber range 400-1800 cm-1. Structural changes induced in genomic DNAs upon cryopreservation were discussed in detail for four of the above mentioned tomato cultivars. The surface-enhanced Raman vibrational modes for each of these cases, spectroscopic band assignments and structural interpretations of genomic DNAs are reported. We have found, that DNA isolated from Siriana cultivar leaf tissues suffers the weakest structural changes upon cryogenic storage of tomato shoot apices. On the contrary, genomic DNA extracted from Pontica cultivar is the most responsive system to cryopreservation process. Particularly, both C2‧-endo-anti and C3'-endo-anti conformations have been detected. As a general observation, the wavenumber range 1511-1652 cm-1, being due to dA, dG and dT residues seems to be influenced by cryopreservation process. These changes could reflect unstacking of DNA bases. However, not significant structural changes of genomic DNAs from Siriana, Darsirius and Kristin have been found upon cryopreservation process of tomato cultivars. Based on this work, specific plant DNA-ligand interactions or accurate local structure of DNA in the proximity of a metallic surface, might be further investigated using surface-enhanced Raman spectroscopy.

Early biotic stress detection in tomato (Solanum lycopersicum) by BVOC emissions.

PubMed

Kasal-Slavik, Tina; Eschweiler, Julia; Kleist, Einhard; Mumm, Roland; Goldbach, Heiner E; Schouten, Alexander; Wildt, Jürgen

2017-12-01

We investigated impacts of early and mild biotic stress on Biogenic Volatile Organic Compounds (BVOC) emissions from tomato in order to test their potential for early (biotic) stress detection. Tomato plants were exposed to two common fungal pathogens, Botrytis cinerea and Oidium neolycopesici and the sap-sucking aphid Myzus persicae. Furthermore, plants were exposed to methyl jasmonate (MeJA) in order to identify BVOC emissions related to activation of jasmonic acid (JA) signalling pathway. These emissions where then used as a reference for identifying active JA signalling pathway in plants at early stages of biotic stress. After infection by the necrotrophic fungus B. cinerea, changes in BVOC emissions indicated that tomato plants had predominantly activated the jasmonic acid (JA) signalling pathway. The plants were able to modify their defence pathways in order to overcome fungal infection. When tomato plants were infected with the biotrophic fungus O. neolycopersici, only minor changes in BVOC emissions were observed with additional emissions of the sesquiterpene α-copaene. α-copaene emissions allowed the identification of general biotic stress in the plants, without pinpointing the actual triggered defence pathway. BVOC emissions during M. persicae attack had changed before the occurrence of visual symptoms. Despite low infestation rates, plants emitted methyl salicylate indicating activation of the SA-mediated defence pathway. Copyright © 2017 Elsevier Ltd. All rights reserved.

Reducing AsA leads to leaf lesion and defence response in knock-down of the AsA biosynthetic enzyme GDP-D-mannose pyrophosphorylase gene in tomato plant.

PubMed

Zhang, Chanjuan; Ouyang, Bo; Yang, Changxian; Zhang, Xiaohui; Liu, Hui; Zhang, Yuyang; Zhang, Junhong; Li, Hanxia; Ye, Zhibiao

2013-01-01

As a vital antioxidant, L-ascorbic acid (AsA) affects diverse biological processes in higher plants. Lack of AsA in cell impairs plant development. In the present study, we manipulated a gene of GDP-mannose pyrophosphorylase which catalyzes the conversion of D-mannose-1-P to GDP-D-mannose in AsA biosynthetic pathway and found out the phenotype alteration of tomato. In the tomato genome, there are four members of GMP gene family and they constitutively expressed in various tissues in distinct expression patterns. As expected, over-expression of SlGMP3 increased total AsA contents and enhanced the tolerance to oxidative stress in tomato. On the contrary, knock-down of SlGMP3 significantly decreased AsA contents below the threshold level and altered the phenotype of tomato plants with lesions and further senescence. Further analysis indicated the causes for this symptom could result from failing to instantly deplete the reactive oxygen species (ROS) as decline of free radical scavenging activity. More ROS accumulated in the leaves and then triggered expressions of defence-related genes and mimic symptom occurred on the leaves similar to hypersensitive responses against pathogens. Consequently, the photosynthesis of leaves was dramatically fallen. These results suggested the vital roles of AsA as an antioxidant in leaf function and defence response of tomato.

The Combination of Trichoderma harzianum and Chemical Fertilization Leads to the Deregulation of Phytohormone Networking, Preventing the Adaptive Responses of Tomato Plants to Salt Stress.

PubMed

Rubio, M B; Hermosa, Rosa; Vicente, Rubén; Gómez-Acosta, Fabio A; Morcuende, Rosa; Monte, Enrique; Bettiol, Wagner

2017-01-01

Plants have evolved effective mechanisms to avoid or reduce the potential damage caused by abiotic stresses. In addition to biocontrol abilities, Trichoderma genus fungi promote growth and alleviate the adverse effects caused by saline stress in plants. Morphological, physiological, and molecular changes were analyzed in salt-stressed tomato plants grown under greenhouse conditions in order to investigate the effects of chemical and biological fertilizations. The application of Trichoderma harzianum T34 to tomato seeds had very positive effects on plant growth, independently of chemical fertilization. The application of salt stress significantly changed the parameters related to growth and gas-exchange rates in tomato plants subject to chemical fertilization. However, the gas-exchange parameters were not affected in unfertilized plants under the same moderate saline stress. The combined application of T34 and salt significantly reduced the fresh and dry weights of NPK-fertilized plants, while the opposite effects were detected when no chemical fertilization was applied. Decaying symptoms were observed in salt-stressed and chemically fertilized plants previously treated with T34. This damaged phenotype was linked to significantly higher intercellular CO 2 and slight increases in stomatal conductance and transpiration, and to the deregulation of phytohormone networking in terms of significantly lower expression levels of the salt overlay sensitivity 1 ( SOS1 ) gene, and the genes involved in signaling abscisic acid-, ethylene-, and salicylic acid-dependent pathways and ROS production, in comparison with those observed in salt-challenged NPK-fertilized plants.

Isolation and composition of chromoplasts from tomatoes.

PubMed

Hansen, Linn U; Chiu, Mei-Chen M

2005-08-24

The fruit of the tomato plant is composed of elongated tomato cells filled with organelles called chromoplasts (plastids). These plastids scattered throughout the cell are rich in nutrients, particularly protein (33%) and lipids (20%). They can be released from the cells by rupture of their cell membranes and then isolated. Plastids and their cell contents can be utilized by the food-processing industry for the preparation of special food products. This study was designed to examine the macronutrient content of isolated tomato plastids and, therefore, determine its potential nutritional value. Use of tomato plastids in pasta sauces and rice dishes, salsa, and extrusion products would increase the nutritional value of the product. Because glucose has been removed in the process of plastid isolation, tomato plastids are useful in the diets of diabetics and cardiovascular patients, as well as for patients in need of weight reduction. Composition comparison of tomato plastid is made with tomato paste, from which glucose has not been removed. Many people require low-sugar products for medical reasons (diabetics and those with cardiovascular disease) and others for weight loss. Therefore, tomato chromoplasts having high protein and lipid contents and low sugar content may be useful in meeting these particular human needs.

Gene expression analysis of the biocontrol fungus Trichoderma harzianum in the presence of tomato plants, chitin, or glucose using a high-density oligonucleotide microarray.

PubMed

Samolski, Ilanit; de Luis, Alberto; Vizcaíno, Juan Antonio; Monte, Enrique; Suárez, M Belén

2009-10-13

It has recently been shown that the Trichoderma fungal species used for biocontrol of plant diseases are capable of interacting with plant roots directly, behaving as symbiotic microorganisms. With a view to providing further information at transcriptomic level about the early response of Trichoderma to a host plant, we developed a high-density oligonucleotide (HDO) microarray encompassing 14,081 Expressed Sequence Tag (EST)-based transcripts from eight Trichoderma spp. and 9,121 genome-derived transcripts of T. reesei, and we have used this microarray to examine the gene expression of T. harzianum either alone or in the presence of tomato plants, chitin, or glucose. Global microarray analysis revealed 1,617 probe sets showing differential expression in T. harzianum mycelia under at least one of the culture conditions tested as compared with one another. Hierarchical clustering and heat map representation showed that the expression patterns obtained in glucose medium clustered separately from the expression patterns observed in the presence of tomato plants and chitin. Annotations using the Blast2GO suite identified 85 of the 257 transcripts whose probe sets afforded up-regulated expression in response to tomato plants. Some of these transcripts were predicted to encode proteins related to Trichoderma-host (fungus or plant) associations, such as Sm1/Elp1 protein, proteases P6281 and PRA1, enchochitinase CHIT42, or QID74 protein, although previously uncharacterized genes were also identified, including those responsible for the possible biosynthesis of nitric oxide, xenobiotic detoxification, mycelium development, or those related to the formation of infection structures in plant tissues. The effectiveness of the Trichoderma HDO microarray to detect different gene responses under different growth conditions in the fungus T. harzianum strongly indicates that this tool should be useful for further assays that include different stages of plant colonization, as well as

Gene expression analysis of the biocontrol fungus Trichoderma harzianum in the presence of tomato plants, chitin, or glucose using a high-density oligonucleotide microarray

PubMed Central

2009-01-01

Background It has recently been shown that the Trichoderma fungal species used for biocontrol of plant diseases are capable of interacting with plant roots directly, behaving as symbiotic microorganisms. With a view to providing further information at transcriptomic level about the early response of Trichoderma to a host plant, we developed a high-density oligonucleotide (HDO) microarray encompassing 14,081 Expressed Sequence Tag (EST)-based transcripts from eight Trichoderma spp. and 9,121 genome-derived transcripts of T. reesei, and we have used this microarray to examine the gene expression of T. harzianum either alone or in the presence of tomato plants, chitin, or glucose. Results Global microarray analysis revealed 1,617 probe sets showing differential expression in T. harzianum mycelia under at least one of the culture conditions tested as compared with one another. Hierarchical clustering and heat map representation showed that the expression patterns obtained in glucose medium clustered separately from the expression patterns observed in the presence of tomato plants and chitin. Annotations using the Blast2GO suite identified 85 of the 257 transcripts whose probe sets afforded up-regulated expression in response to tomato plants. Some of these transcripts were predicted to encode proteins related to Trichoderma-host (fungus or plant) associations, such as Sm1/Elp1 protein, proteases P6281 and PRA1, enchochitinase CHIT42, or QID74 protein, although previously uncharacterized genes were also identified, including those responsible for the possible biosynthesis of nitric oxide, xenobiotic detoxification, mycelium development, or those related to the formation of infection structures in plant tissues. Conclusion The effectiveness of the Trichoderma HDO microarray to detect different gene responses under different growth conditions in the fungus T. harzianum strongly indicates that this tool should be useful for further assays that include different stages of

Growth and development of tomato plants Lycopersicon Esculentum Mill. under different saline conditions by fertirrigation with pretreated cheese whey wastewater.

PubMed

Prazeres, Ana R; Carvalho, Fátima; Rivas, Javier; Patanita, Manuel; Dôres, Jóse

2013-01-01

Pretreated cheese whey wastewater (CWW) has been used at different salinity levels: 1.75, 2.22, 3.22, 5.02 and 10.02 dS m(-1) and compared with fresh water (1.44 dS m(-1)). Two cultivars (cv.) of the tomato plant Lycopersicon Esculentum Mill. (Roma and Rio Grande) were exposed to saline conditions for 72 days. Salinity level (treatment) had no significant effects on the fresh weight and dry matter of the leaves, stems and roots. Similar results were found when specific leaf area, leaflet area, ramifications number of 1st order/plant, stem diameter and length, nodes number/stem and primary root length were considered. Conversely, the salinity level significantly influenced the Soil Plant Analysis Development (SPAD) index and the distance between nodes in the plant stem. In the first case, an increase of 21% was obtained in the salinity levels of 5.02 and 10.02 dS m(-1) for cv. Rio Grande, compared with the control run. The results showed that the pretreated CWW can be a source of nutrients for tomato plants, with reduced effects on growth and development.

The ACC deaminase expressing endophyte Pseudomonas spp. Enhances NaCl stress tolerance by reducing stress-related ethylene production, resulting in improved growth, photosynthetic performance, and ionic balance in tomato plants.

PubMed

Win, Khin Thuzar; Fukuyo, Tanaka; Keiki, Okazaki; Ohwaki, Yoshinari

2018-06-01

Plant growth promoting bacteria (PGPB) endophytes that express 1-aminocyclopropane-1-carboxylate (ACC) deaminase reportedly confer plant tolerance to abiotic stresses such as salinity by lowering stress-related ethylene levels. Two preselected ACC deaminase expressing endophytic Pseudomonas spp. strains, OFT2 and OFT5, were compared in terms of their potential to promote plant growth, leaf water contents, photosynthetic performance, and ionic balance of tomato plants under conditions of moderate NaCl stress (75 mM). Salinity stress strongly affected growth, leaf water contents, and photosynthetic performance of tomato seedlings, and inoculation with either OFT2 or OFT5 ameliorated these adverse effects. Decreases in plant biomass due to salinity stress were significant in both uninoculated control plants and in plants inoculated with OFT2 compared with plants without NaCl stress. However, no reductions in total biomass were observed in plants that were inoculated with the OFT5 strain. Strain OFT5 influenced growth, physiological status, and ionic balance of tomato plants more efficiently than strain OFT2 under NaCl stress. In particular, inoculated OFT5 reduced salt-induced ethylene production by tomato seedlings, and although it did not reduce shoot uptake of Na, it promoted shoot uptake of other macronutrients (P, K, and Mg) and micronutrients (Mn, Fe, Cu, and Zn). These nutrients may activate processes that alleviate the effects of salt, suggesting that OFT5 can be used to improve nutrient uptake and plant growth under moderate salt-affected conditions by reducing stress-related ethylene levels. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

High invertase activity in tomato reproductive organs correlates with enhanced sucrose import into, and heat tolerance of, young fruit

PubMed Central

Li, Zhimiao; Palmer, William M.; Martin, Antony P.; Wang, Rongqing; Rainsford, Frederick; Jin, Ye; Patrick, John W.; Yang, Yuejian; Ruan, Yong-Ling

2012-01-01

Heat stress can cause severe crop yield losses by impairing reproductive development. However, the underlying mechanisms are poorly understood. We examined patterns of carbon allocation and activities of sucrose cleavage enzymes in heat-tolerant (HT) and -sensitive (HS) tomato (Solanum lycopersicum L.) lines subjected to normal (control) and heat stress temperatures. At the control temperature of 25/20 °C (day/night) the HT line exhibited higher cell wall invertase (CWIN) activity in flowers and young fruits and partitioned more sucrose to fruits but less to vegetative tissues as compared to the HS line, independent of leaf photosynthetic capacity. Upon 2-, 4-, or 24-h exposure to day or night temperatures of 5 °C or more above 25/20 °C, cell wall (CWIN) and vacuolar invertases (VIN), but not sucrose synthase (SuSy), activities in young fruit of the HT line were significantly higher than those of the HS line. The HT line had a higher level of transcript of a CWIN gene, Lin7, in 5-day fruit than the HS line under control and heat stress temperatures. Interestingly, heat induced transcription of an invertase inhibitor gene, INVINH1, but reduced its protein abundance. Transcript levels of LePLDa1, encoding phospholipase D, which degrades cell membranes, was less in the HT line than in the HS line after exposure to heat stress. The data indicate that high invertase activity of, and increased sucrose import into, young tomato fruit could contribute to their heat tolerance through increasing sink strength and sugar signalling activities, possibly regulating a programmed cell death pathway. PMID:22105847

Automatic Detection of Diseased Tomato Plants Using Thermal and Stereo Visible Light Images

PubMed Central

Raza, Shan-e-Ahmed; Prince, Gillian; Clarkson, John P.; Rajpoot, Nasir M.

2015-01-01

Accurate and timely detection of plant diseases can help mitigate the worldwide losses experienced by the horticulture and agriculture industries each year. Thermal imaging provides a fast and non-destructive way of scanning plants for diseased regions and has been used by various researchers to study the effect of disease on the thermal profile of a plant. However, thermal image of a plant affected by disease has been known to be affected by environmental conditions which include leaf angles and depth of the canopy areas accessible to the thermal imaging camera. In this paper, we combine thermal and visible light image data with depth information and develop a machine learning system to remotely detect plants infected with the tomato powdery mildew fungus Oidium neolycopersici. We extract a novel feature set from the image data using local and global statistics and show that by combining these with the depth information, we can considerably improve the accuracy of detection of the diseased plants. In addition, we show that our novel feature set is capable of identifying plants which were not originally inoculated with the fungus at the start of the experiment but which subsequently developed disease through natural transmission. PMID:25861025

Detection of Expansin Proteins and Activity during Tomato Fruit Ontogeny1

PubMed Central

Rose, Jocelyn K.C.; Cosgrove, Daniel J.; Albersheim, Peter; Darvill, Alan G.; Bennett, Alan B.

2000-01-01

Expansins are plant proteins that have the capacity to induce extension in isolated cell walls and are thought to mediate pH-dependent cell expansion. J.K.C. Rose, H.H. Lee, and A.B. Bennett ([1997] Proc Natl Acad Sci USA 94: 5955–5960) reported the identification of an expansin gene (LeExp1) that is specifically expressed in ripening tomato (Lycopersicon esculentum) fruit where cell wall disassembly, but not cell expansion, is prominent. Expansin expression during fruit ontogeny was examined using antibodies raised to recombinant LeExp1 or a cell elongation-related expansin from cucumber (CsExp1). The LeExp1 antiserum detected expansins in extracts from ripe, but not preripe tomato fruit, in agreement with the pattern of LeExp1 mRNA accumulation. In contrast, antibodies to CsExp1 cross-reacted with expansins in early fruit development and the onset of ripening, but not at a later ripening stage. These data suggest that ripening-related and expansion-related expansin proteins have distinct antigenic epitopes despite overall high sequence identity. Expansin proteins were detected in a range of fruit species and showed considerable variation in abundance; however, appreciable levels of expansin were not present in fruit of the rin or Nr tomato mutants that exhibit delayed and reduced softening. LeExp1 protein accumulation was ethylene-regulated and matched the previously described expression of mRNA, suggesting that expression is not regulated at the level of translation. We report the first detection of expansin activity in several stages of fruit development and while characteristic creep activity was detected in young and developing tomato fruit and in ripe pear, avocado, and pepper, creep activity in ripe tomato showed qualitative differences, suggesting both hydrolytic and expansin activities. PMID:10938374

The translocation and distribution of CeO2 nanoparticles in plants (Soybeans, Chili, Eggplant and Tomato)

NASA Astrophysics Data System (ADS)

Li, Teng; Dai, Yanhui

2018-02-01

Intensive production of CeO2 nanoparticles (NPs) would lead to their release into the environment. While their use in commercial goods is constantly increasing, location of NPs in plant is still poorly documented. In this study we determined the translocation of CeO2-NPs in four plants (Soybeans, Tomato, Chili and Eggplant) grown in natural conditions. The plants were digged out 1/4 roots into 2000 mg/L CeO2-NPs solution during the blossoming period. After being exposed for one month, the contents of Ce in plant tissues were measured by inductively coupled plasma mass spectrometry (ICP-MS). There was more Ce in the leaf of treated plants than in control plants. The contents of Ce in leaf tissues was different. This research offers vital information about the translocation and distribution of CeO2-NPs in higher plants.

Some fungal endophytes from vegetable crops and their anti-oomycete activities against tomato late blight.

PubMed

Kim, H-Y; Choi, G J; Lee, H B; Lee, S-W; Lim, H K; Jang, K S; Son, S W; Lee, S O; Cho, K Y; Sung, N D; Kim, J-C

2007-03-01

To isolate endophytic fungi from vegetable plants and examine their in vivo anti-oomycete activity against Phytophthora infestans in tomato plants. Endophytic fungi were isolated from surface-sterilized plant tissues and anti-oomycete activity was measured by in vivo assay using tomato seedlings. Endophytic fungi showing potent anti-oomycete activity were identified by morphological characteristics and nuclear ribosomal ITS1-5.8S-ITS2 sequence analysis. A total of 152 isolates were obtained from 66 healthy tissue samples of cucumber, red pepper, tomato, pumpkin and Chinese cabbage and the fermentation broths of 23 isolates showed potent in vivo anti-oomycete activity against tomato late blight with control values over 90%. The Fusarium oxysporum strain EF119, which was isolated from roots of red pepper, showed the most potent disease control efficacy against tomato late blight. In dual-culture tests, it inhibited the growth of Pythium ultimum, P. infestans and Phytophthora capsici. Among endophytic fungi isolated from healthy tissues of vegetable plants, F. oxysporum EF119 showed the most potent in vivo anti-oomycete activity against tomato late blight and in vitro anti-oomycete activity against several oomycete pathogens. Endophytic fungi showing anti-oomycete activity in vitro and in vivo may be used as biocontrol agents particularly of tomato late blight.

The history of tomato: from domestication to biopharming.

PubMed

Bergougnoux, Véronique

2014-01-01

Imported from the Andean region to Europe in the 16th century, today tomato is widespread throughout the world and represents the most economically important vegetable crop worldwide. Tomato is not only traded in the fresh market but is also used in the processing industry in soups, as paste, concentrate, juice, and ketchup. It is an incredible source of important nutrients such as lycopene, β-carotene and vitamin C, which all have positive impacts on human health. Its production and consumption is increasing with population growth. In this review, we report how tomato was already domesticated by the ancient Incan and Aztec civilizations, and how it came to Europe, where its breeding history started. The development of genetic, molecular biology and plant biotechnology have opened the doors towards the modern genetic engineering of tomato. The different goals of tomato genetic engineering are presented, as well as examples of successfully engineered tomatoes in terms of resistance to biotic and abiotic stresses, and fruit quality. The development of GM tomato for biopharming is also described. Copyright © 2013 Elsevier Inc. All rights reserved.

The Dynamics of Embolism Refilling in Abscisic Acid (ABA)-Deficient Tomato Plants

PubMed Central

Secchi, Francesca; Perrone, Irene; Chitarra, Walter; Zwieniecka, Anna K.; Lovisolo, Claudio; Zwieniecki, Maciej A.

2013-01-01

Plants are in danger of embolism formation in xylem vessels when the balance between water transport capacity and transpirational demand is compromised. To maintain this delicate balance, plants must regulate the rate of transpiration and, if necessary, restore water transport in embolized vessels. Abscisic acid (ABA) is the dominant long-distance signal responsible for plant response to stress, and it is possible that it plays a role in the embolism/refilling cycle. To test this idea, a temporal analysis of embolism and refilling dynamics, transpiration rate and starch content was performed on ABA-deficient mutant tomato plants. ABA-deficient mutants were more vulnerable to embolism formation than wild-type plants, and application of exogenous ABA had no effect on vulnerability. However, mutant plants treated with exogenous ABA had lower stomatal conductance and reduced starch content in the xylem parenchyma cells. The lower starch content could have an indirect effect on the plant’s refilling activity. The results confirm that plants with high starch content (moderately stressed mutant plants) were more likely to recover from loss of water transport capacity than plants with low starch content (mutant plants with application of exogenous ABA) or plants experiencing severe water stress. This study demonstrates that ABA most likely does not play any direct role in embolism refilling, but through the modulation of carbohydrate content, it could influence the plant’s capacity for refilling. PMID:23263667

Effect of textile waste water on tomato plant, Lycopersicon esculentum.

PubMed

Marwari, Richa; Khan, T I

2012-09-01

In this study Sanganer town, Jaipur was selected as study area. The plants of Lycopersicon esculentum var. K 21(Tomato) treated with 20 and 30% textile wastewater were analyzed for metal accumulation, growth and biochemical parameters at per, peak and post flowering stages. Findings of the study revealed that chlorophyll content was most severely affected with the increase in metal concentration. Total chlorophyll content showed a reduction of 72.44% while carbohydrate, protein and nitrogen content showed a reduction of 46.83, 71.65 and 71.65% respectively. With the increase in waste water treatment the root and shoot length, root and shoot dry weight and total dry weight were reduced to 50.55, 52.06, 69.93, 72.42, 72.10% respectively. After crop harvesting, the fruit samples of the plants treated with highest concentration of textile waste water contained 2.570 mg g(-1)d.wt. of Zn, 0.800 mg g(-1) d.wt. Cu, 1.520 mg g(-1) d.wt. Cr and 2.010 mg g(-1) d.wt. Pb.

Clustering and cellular distribution characteristics of virus particles of Tomato spotted wilt virus and Tomato zonate spot virus in different plant hosts.

PubMed

Zhang, Zhongkai; Zheng, Kuanyu; Dong, Jiahong; Fang, Qi; Hong, Jian; Wang, Xifeng

2016-01-19

Tomato spotted wilt virus (TSWV) and Tomato zonate spot virus (TZSV) are the two dominant species of thrip-transmitted tospoviruses, cause significant losses in crop yield in Yunnan and its neighboring provinces in China. TSWV and TZSV belong to different serogroup of tospoviruses but induce similar symptoms in the same host plant species, which makes diagnostic difficult. We used different electron microscopy preparing methods to investigate clustering and cellular distribution of TSWV and TZSV in the host plant species. Negative staining of samples infected with TSWV and TZSV revealed that particles usually clustered in the vesicles, including single particle (SP), double particles clustering (DPC), triple particles clustering (TPC). In the immunogold labeling negative staining against proteins of TZSV, the antibodies against Gn protein were stained more strongly than the N protein. Ultrathin section and high pressure freeze (HPF)-electron microscopy preparations revealed that TSWV particles were distributed in the cisternae of endoplasmic reticulum (ER), filamentous inclusions (FI) and Golgi bodies in the mesophyll cells. The TSWV particles clustered as multiple particles clustering (MPC) and distributed in globular viroplasm or cisternae of ER in the top leaf cell. TZSV particles were distributed more abundantly in the swollen membrane of ER in the mesophyll cell than those in the phloem parenchyma cells and were not observed in the top leaf cell. However, TZSV virions were mainly present as single particle in the cytoplasm, with few clustering as MPC. In this study, we identified TSWV and TZSV particles had the distinct cellular distribution patterns in the cytoplasm from different tissues and host plants. This is the first report of specific clustering characteristics of tospoviruses particles as well as the cellular distribution of TSWV particles in the FI and globular viroplasm where as TZSV particles inside the membrane of ER. These results indicated that

Control of Plant Trichome and Root-Hair Development by a Tomato (Solanum lycopersicum) R3 MYB Transcription Factor

PubMed Central

Tominaga-Wada, Rumi; Nukumizu, Yuka; Sato, Shusei; Wada, Takuji

2013-01-01

In Arabidopsis thaliana the CPC-like MYB transcription factors [CAPRICE (CPC), TRIPTYCHON (TRY), ENHANCER OF TRY AND CPC 1, 2, 3/CPC-LIKE MYB 3 (ETC1, ETC2, ETC3/CPL3), TRICHOMELESS 1, 2/CPC-LIKE MYB 4 (TCL1, TCL2/CPL4)] and the bHLH transcription factors [GLABRA3 (GL3) and ENHANCER OF GLABRA 3 (EGL3)] are central regulators of trichome and root-hair development. We identified TRY and GL3 homologous genes from the tomato genome and named them SlTRY and SlGL3, respectively. Phylogenic analyses revealed a close relationship between the tomato and Arabidopsis genes. Real-time reverse transcription PCR analyses showed that SlTRY and SlGL3 were predominantly expressed in aerial parts of developing tomato. After transformation into Arabidopsis, CPC::SlTRY inhibited trichome formation and enhanced root-hair differentiation by strongly repressing GL2 expression. On the other hand, GL3::SlGL3 transformation did not show any obvious effect on trichome or non-hair cell differentiation. These results suggest that tomato and Arabidopsis partially use similar transcription factors for epidermal cell differentiation, and that a CPC-like R3 MYB may be a key common regulator of plant trichome and root-hair development. PMID:23326563

Application of plant impedance for diagnosing plant disease

NASA Astrophysics Data System (ADS)

Xu, Huirong; Jiang, Xuesong; Zhu, Shengpan; Ying, Yibin

2006-10-01

Biological cells have components acting as electrical elements that maintain the health of the cell by regulation of the electrical charge content. Plant impedance is decided by the state of plant physiology and pathology. Plant physiology and pathology can be studies by measuring plant impedance. The effect of Cucumber Mosaic Virus red bean isolate (CMV-RB) on electrical resistance of tomato leaves was studied by the method of impedance measurement. It was found that the value of resistance of tomato leaves infected with CMV-RB was smaller than that in sound plant leaves. This decrease of impedances in leaf tissue was occurred with increased severity of disease. The decrease of resistance of tomato leaves infected with CMV-RB could be detected by electrical resistance detecting within 4 days after inoculation even though significant visible differences between the control and the infected plants were not noted, so that the technique for measurement of tomato leaf tissue impedance is a rapid, clever, simple method on diagnosis of plant disease.

Functional characterization of an invertase inhibitor gene involved in sucrose metabolism in tomato fruit.

PubMed

Zhang, Ning; Jiang, Jing; Yang, Yan-li; Wang, Zhi-he

2015-10-01

In this study, we produced tomato plants overexpressing an invertase inhibitor gene (Sly-INH) from tomato, using a simple and efficient transient transformation system. Compared with control plants, the expression of Sly-INH was highly upregulated in Sly-INH overexpressing plants, as indicated by real-time polymerase chain reaction (PCR). Physiological analysis revealed that Sly-INH inhibited the activity of cell wall invertase (CWIN), which increased sugar accumulation in tomato fruit. Furthermore, Sly-INH mediated sucrose metabolism by regulating CWIN activity. Our results suggest that invertase activity is potentially regulated by the Sly-INH inhibitor at the post-translational level, and they demonstrate that the transient transformation system is an effective method for determining the functions of genes in tomato.

Abscisic Acid Determines Basal Susceptibility of Tomato to Botrytis cinerea and Suppresses Salicylic Acid-Dependent Signaling Mechanisms1

PubMed Central

Audenaert, Kris; De Meyer, Geert B.; Höfte, Monica M.

2002-01-01

Abscisic acid (ABA) is one of the plant hormones involved in the interaction between plants and pathogens. In this work, we show that tomato (Lycopersicon esculentum Mill. cv Moneymaker) mutants with reduced ABA levels (sitiens plants) are much more resistant to the necrotrophic fungus Botrytis cinerea than wild-type (WT) plants. Exogenous application of ABA restored susceptibility to B. cinerea in sitiens plants and increased susceptibility in WT plants. These results indicate that ABA plays a major role in the susceptibility of tomato to B. cinerea. ABA appeared to interact with a functional plant defense response against B. cinerea. Experiments with transgenic NahG tomato plants and benzo(1,2,3)thiadiazole-7-carbothioic acid demonstrated the importance of salicylic acid in the tomato-B. cinerea interaction. In addition, upon infection with B. cinerea, sitiens plants showed a clear increase in phenylalanine ammonia lyase activity, which was not observed in infected WT plants, indicating that the ABA levels in healthy WT tomato plants partly repress phenylalanine ammonia lyase activity. In addition, sitiens plants became more sensitive to benzo(1,2,3)thiadiazole-7-carbothioic acid root treatment. The threshold values for PR1a gene expression declined with a factor 10 to 100 in sitiens compared with WT plants. Thus, ABA appears to negatively modulate the salicylic acid-dependent defense pathway in tomato, which may be one of the mechanisms by which ABA levels determine susceptibility to B. cinerea. PMID:11842153

Western flower thrips can transmit Tomato spotted wilt virus from infected tomato fruits

USDA-ARS?s Scientific Manuscript database

Tomato spotted wilt virus (TSWV) has long been known to spread via plant propagation materials including transplants. Global dissemination of TSWV has also been linked to transport of thrips-infested and virus-infected horticultural and floricultural products through trade and commerce. However, th...

Surface-enhanced Raman spectroscopy of genomic DNA from in vitro grown tomato (Lycopersicon esculentum Mill.) cultivars before and after plant cryopreservation.

PubMed

Muntean, Cristina M; Leopold, Nicolae; Tripon, Carmen; Coste, Ana; Halmagyi, Adela

2015-06-05

In this work the surface-enhanced Raman scattering (SERS) spectra of five genomic DNAs from non-cryopreserved control tomato plants (Lycopersicon esculentum Mill. cultivars Siriana, Darsirius, Kristin, Pontica and Capriciu) respectively, have been analyzed in the wavenumber range 400-1800 cm(-1). Structural changes induced in genomic DNAs upon cryopreservation were discussed in detail for four of the above mentioned tomato cultivars. The surface-enhanced Raman vibrational modes for each of these cases, spectroscopic band assignments and structural interpretations of genomic DNAs are reported. We have found, that DNA isolated from Siriana cultivar leaf tissues suffers the weakest structural changes upon cryogenic storage of tomato shoot apices. On the contrary, genomic DNA extracted from Pontica cultivar is the most responsive system to cryopreservation process. Particularly, both C2'-endo-anti and C3'-endo-anti conformations have been detected. As a general observation, the wavenumber range 1511-1652 cm(-1), being due to dA, dG and dT residues seems to be influenced by cryopreservation process. These changes could reflect unstacking of DNA bases. However, not significant structural changes of genomic DNAs from Siriana, Darsirius and Kristin have been found upon cryopreservation process of tomato cultivars. Based on this work, specific plant DNA-ligand interactions or accurate local structure of DNA in the proximity of a metallic surface, might be further investigated using surface-enhanced Raman spectroscopy. Copyright © 2015 Elsevier B.V. All rights reserved.

Improvement of tomato local varieties by grafting in organic farming

NASA Astrophysics Data System (ADS)

Moreno, Marta M.; Villena, Jaime; Moreno, Carmen; García, Arántzazu M.; Mancebo, Ignacio; Meco, Ramón

2015-04-01

Grafting is the union of two or more pieces of living plant tissue that grow as a single plant. The early use of grafted vegetables was associated with protected cultivation which involves successive cropping (Lee et al., 2010). For this reason, in the past, grafting was used with vegetable crops to limit the effects of soil-borne diseases. However, the reasons for grafting as well as the kinds of vegetable grafted have increased considerably over the years. In tomato (Solanum lycopersicum L.), one of the most important horticultural crops in the world, the effect of grafting has also been widely studied. These effects on commercial tomato varieties can be summarized in increasing plant vigor and crop yield or inducing tolerance to abiotic stresses, although the effects on tomato fruit quality or on the sensory properties are not so patent (David et al., 2008). However, a few studies about the effect of grafting on local tomato varieties, which are especially recommended for organic production in spite of their lower yields in many cases, have been developed. In this work we evaluated the effect of grafting on tomato local varieties under organic management using vigorous commercial rootstocks, and aspects related to vigor, yield and tomato fruit composition were analyzed. In general terms, grafting increased the plant vigor, the crop yield and the fruit antioxidant content, although no modification of morphological fruit attributes was observed. Keywords: grafting, Solanum lycopersicum L., local varieties, organic farming. References: Davis A.R., Perkins-Veazie P., Hassell R., Levi A., King S.R., Zhang X. 2008. Grafting effects on vegetable quality. HortScience 43(6): 1670-1671. Lee J.M., Kubota C., Tsao S.J., Bie Z., Hoyos-Echevarría P., Morra L., Oda M. 2010. Current status of vegetable grafting: Diffusion, grafting techniques, automation. Scientia Horticulturae 127: 93-105.

Growth of plants in solution culture containing low levels of chromium. [Tomato, lettuce, duckweed

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huffman, E.W.D. Jr.; Allaway, W.H.

1973-01-01

Chromium was not required for normal growth of romaine lettuce (Lactuca sativa L. subsp. longifolia), tomato (Lycopersicon esculentum Mill.), wheat (Triticum aestivum L.), or bean (Phaseolus vulgaris L.) in solution culture containing 3.8 X 10/sup -4/ ..mu..M Cr. Plants grown on this purified nutrient solution contained an average of 22 ng Cr/g dry weight. Duckweed (Lemna sp.) grew and reproduced normally on a dilute nutrient solution containing 3.8 X 20/sup -5/ ..mu..M Cr.

Different mechanisms of Trichoderma virens-mediated resistance in tomato against Fusarium wilt involve the jasmonic and salicylic acid pathways.

PubMed

Jogaiah, Sudisha; Abdelrahman, Mostafa; Tran, Lam-Son Phan; Ito, Shin-Ichi

2018-04-01

In the present study, we investigated the role of Trichoderma virens (TriV_JSB100) spores or cell-free culture filtrate in the regulation of growth and activation of the defence responses of tomato (Solanum lycopersicum) plants against Fusarium oxysporum f. sp. lycopersici by the development of a biocontrol-plant-pathogen interaction system. Two-week-old tomato seedlings primed with TriV_JSB100 spores cultured on barley grains (BGS) or with cell-free culture filtrate (CF) were inoculated with Fusarium pathogen under glasshouse conditions; this resulted in significantly lower disease incidence in tomato Oogata-Fukuju plants treated with BGS than in those treated with CF. To dissect the pathways associated with this response, jasmonic acid (JA) and salicylic acid (SA) signalling in BGS- and CF-induced resistance was evaluated using JA- and SA-impaired tomato lines. We observed that JA-deficient mutant def1 plants were susceptible to Fusarium pathogen when they were treated with BGS. However, wild-type (WT) BGS-treated tomato plants showed a higher JA level and significantly lower disease incidence. SA-deficient mutant NahG plants treated with CF were also found to be susceptible to Fusarium pathogen and displayed low SA levels, whereas WT CF-treated tomato plants exhibited moderately lower disease levels and substantially higher SA levels. Expression of the JA-responsive defensin gene PDF1 was induced in WT tomato plants treated with BGS, whereas the SA-inducible pathogenesis-related protein 1 acidic (PR1a) gene was up-regulated in WT tomato plants treated with CF. These results suggest that TriV_JSB100 BGS and CF differentially induce JA and SA signalling cascades for the elicitation of Fusarium oxysporum resistance in tomato. © 2017 BSPP AND JOHN WILEY & SONS LTD.

The tomato plastidic fructokinase SlFRK3 plays a role in xylem development.

PubMed

Stein, Ofer; Damari-Weissler, Hila; Secchi, Francesca; Rachmilevitch, Shimon; German, Marcelo A; Yeselson, Yelena; Amir, Rachel; Schaffer, Arthur; Holbrook, N Michele; Aloni, Roni; Zwieniecki, Maciej A; Granot, David

2016-03-01

Plants have two kinds of fructokinases (FRKs) that catalyze the key step of fructose phosphorylation, cytosolic and plastidic. The major cytosolic tomato FRK, SlFRK2, is essential for the development of xylem vessels. In order to study the role of SlFRK3, which encodes the only plastidic FRK, we generated transgenic tomato (Solanum lycopersicon) plants with RNAi suppression of SlFRK3 as well as plants expressing beta-glucoronidase (GUS) under the SlFRK3 promoter. GUS staining indicated SlFRK3 expression in vascular tissues of the leaves and stems, including cambium, differentiating xylem, young xylem fibers and phloem companion cells. Suppression of SlFRK3 reduced the stem xylem area, stem and root water conductance, and whole-plant transpiration, with minor effects on plant development. However, suppression of SlFRK3 accompanied by partial suppression of SlFRK2 induced significant growth-inhibition effects, including the wilting of mature leaves. Grafting experiments revealed that these growth effects are imposed primarily by the leaves, whose petioles had unlignified, thin-walled xylem fibers with collapsed parenchyma cells around the vessels. A cross between the SlFRK2-antisense and SlFRK3-RNAi lines exhibited similar wilting and anatomical effects, confirming that these effects are the result of the combined suppression of SlFRK3 and SlFRK2. These results demonstrate a role of the plastidic SlFRK3 in xylem development and hydraulic conductance. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

Oxidative Stress and Antioxidants in Tomato (Solanum lycopersicum) Plants Subjected to Boron Toxicity

PubMed Central

Cervilla, Luis M.; Blasco, Begoña; Ríos, Juan J.; Romero, Luis; Ruiz, Juan M.

2007-01-01

Background and Aims Boron (B) toxicity triggers the formation of reactive oxygen species in plant tissues. However, there is still a lack of knowledge as to how B toxicity affects the plant antioxidant defence system. It has been suggested that ascorbate could be important against B stress, although existing information is limited in this respect. The objective of this study was to analyse how ascorbate and some other components of the antioxidant network respond to B toxicity. Methods Two tomato (Solanum lycopersicum) cultivars (‘Kosaco’ and ‘Josefina’) were subjected to 0·05 (control), 0·5 and 2 mm B. The following were studied in leaves: dry weight; relative leaf growth rate; total and free B; H2O2; malondialdehyde; ascorbate; glutathione; sugars; total non-enzymatic antioxidant activity, and the activity of superoxide dismutase, catalase, ascorbate peroxidase, monodehydroascorbate reductase, dehydroascorbate reductase, glutathione reductase, ascorbate oxidase and l-galactose dehydrogenase. Key Results The B-toxicity treatments diminished growth and boosted the amount of B, malondialdehyde and H2O2 in the leaves of the two cultivars, these trends being more pronounced in ‘Josefina’ than in ‘Kosaco’. B toxicity increased ascorbate concentration in both cultivars and increased glutathione only in ‘Kosaco’. Activities of antioxidant- and ascorbate-metabolizing enzymes were also induced. Conclusions High B concentration in the culture medium provokes oxidative damage in tomato leaves and induces a general increase in antioxidant enzyme activity. In particular, B toxicity increased ascorbate pool size. It also increased the activity of l-galactose dehydrogenase, an enzyme involved in ascorbate biosynthesis, and the activity of enzymes of the Halliwell–Asada cycle. This work therefore provides a starting point towards a better understanding of the role of ascorbate in the plant response against B stress. PMID:17660516

A Robust Deep-Learning-Based Detector for Real-Time Tomato Plant Diseases and Pests Recognition

PubMed Central

Yoon, Sook; Kim, Sang Cheol; Park, Dong Sun

2017-01-01

Plant Diseases and Pests are a major challenge in the agriculture sector. An accurate and a faster detection of diseases and pests in plants could help to develop an early treatment technique while substantially reducing economic losses. Recent developments in Deep Neural Networks have allowed researchers to drastically improve the accuracy of object detection and recognition systems. In this paper, we present a deep-learning-based approach to detect diseases and pests in tomato plants using images captured in-place by camera devices with various resolutions. Our goal is to find the more suitable deep-learning architecture for our task. Therefore, we consider three main families of detectors: Faster Region-based Convolutional Neural Network (Faster R-CNN), Region-based Fully Convolutional Network (R-FCN), and Single Shot Multibox Detector (SSD), which for the purpose of this work are called “deep learning meta-architectures”. We combine each of these meta-architectures with “deep feature extractors” such as VGG net and Residual Network (ResNet). We demonstrate the performance of deep meta-architectures and feature extractors, and additionally propose a method for local and global class annotation and data augmentation to increase the accuracy and reduce the number of false positives during training. We train and test our systems end-to-end on our large Tomato Diseases and Pests Dataset, which contains challenging images with diseases and pests, including several inter- and extra-class variations, such as infection status and location in the plant. Experimental results show that our proposed system can effectively recognize nine different types of diseases and pests, with the ability to deal with complex scenarios from a plant’s surrounding area. PMID:28869539

The Effect of Spectral Quality on Daily Patterns of Gas Exchange, Biomass Gain, and Water-Use-Efficiency in Tomatoes and Lisianthus: An Assessment of Whole Plant Measurements

PubMed Central

Lanoue, Jason; Leonardos, Evangelos D.; Ma, Xiao; Grodzinski, Bernard

2017-01-01

Advancements in light-emitting diode (LED) technology have made them a viable alternative to current lighting systems for both sole and supplemental lighting requirements. Understanding how wavelength specific LED lighting can affect plants is thus an area of great interest. Much research is available on the wavelength specific responses of leaves from multiple crops when exposed to long-term wavelength specific lighting. However, leaf measurements do not always extrapolate linearly to the complexities which are found within a whole plant canopy, namely mutual shading and leaves of different ages. Taken together, both tomato (Solanum lycopersicum) leaves under short-term illumination and lisianthus (Eustoma grandiflorum) and tomato whole plant diurnal patterns of plants acclimated to specific lighting indicate wavelength specific responses of both H2O and CO2 gas exchanges involved in the major growth parameters of a plant. Tomato leaves grown under a white light source indicated an increase in transpiration rate and internal CO2 concentration and a subsequent decrease in water-use-efficiency (WUE) when exposed to a blue LED light source compared to a green LED light source. Interestingly, the maximum photosynthetic rate was observed to be similar. Using plants grown under wavelength specific supplemental lighting in a greenhouse, a decrease in whole plant WUE was seen in both crops under both red-blue (RB) and red-white (RW) LEDs when compared to a high pressure sodium (HPS) light. Whole plant WUE was decreased by 31% under the RB LED treatment for both crops compared to the HPS treatment. Tomato whole plant WUE was decreased by 25% and lisianthus whole plant WUE was decreased by 15% when compared to the HPS treatment when grown under RW LED. The understanding of the effects of wavelength specific lighting on both leaf and whole plant gas exchange has significant implications on basic academic research as well as commercial greenhouse production. PMID:28676816

Transgenic tomatoes expressing human beta-amyloid for use as a vaccine against Alzheimer's disease.

PubMed

Youm, Jung Won; Jeon, Jae Heung; Kim, Hee; Kim, Young Ho; Ko, Kisung; Joung, Hyouk; Kim, Hyunsoon

2008-10-01

Human beta-amyloid (Abeta) is believed to be one of the main components of Alzheimer's disease, so reduction of Abeta is considered a key therapeutic target. Using Agrobacterium-mediated nuclear transformation, we generated transgenic tomatoes for Abeta with tandem repeats. Integration of the human Abeta gene into the tomato genome and its transcription were detected by PCR and Northern blot, respectively. Expression of the Abeta protein was confirmed by western blot and ELISA, and then the transgenic tomato line expressing the highest protein level was selected for vaccination. Mice immunized orally with total soluble extracts from the transgenic tomato plants elicited an immune response after receiving a booster. The results indicate that tomato plants may provide a useful system for the production of human Abeta antigen.

Exposure to Dust and Endotoxin of Employees in Cucumber and Tomato Nurseries

PubMed Central

Madsen, A. M.; Hansen, V. M.; Nielsen, S. H.; Olsen, T. T.

2009-01-01

Exposure to bioaerosols in occupational settings is associated with a range of adverse health effects. The aim of this study was to investigate the exposure levels to dust and endotoxin of people working in two cucumber nurseries and two tomato nurseries. Exposure was measured for greenhouse workers (n = 70) mainly working on harvesting cucumbers and tomatoes and clearing the plants after the harvest season. The people were exposed to between 0.2 and 15 mg inhalable dust m−3 (median = 1.6 mg m−3) and between 0.5 and 400 ng inhalable endotoxin m−3 (median = 32 ng m−3). The exposure to ‘total dust’ and endotoxin measured by stationary samplers (n = 30) in the greenhouses was low. Endotoxin was present in relatively high concentrations on cucumber leaves compared with leaves on pot plants. The Danish occupational exposure limit (OEL) for total organic dust is 3 mg m−3 and 36% and 17% of the cucumber and tomato workers, respectively, were exposed to >3.0 mg inhalable dust m−3. There is no OEL for endotoxin, but ‘no effect levels’ at ∼15 ng m−3 have been found. The majority of subjects (65%) were exposed to >15 ng m−3. Significantly higher exposure was found for employees in cucumber nurseries than for employees in tomato nurseries. Clearing tomato plants after the harvest season caused a higher exposure to endotoxin than tomato harvesting. In conclusion, people working in cucumber and tomato nurseries were often exposed to high levels of inhalable dust and endotoxin. Cucumber harvest workers were exposed to significantly more dust and endotoxin than tomato harvest workers. The dust and endotoxin aerosolized during the working processes were only transported to other areas in the greenhouses to a very low degree. Cucumber and tomato leaves were identified as endotoxin reservoirs. PMID:19033558

Classification and phylogenetic analyses of the Arabidopsis and tomato G-type lectin receptor kinases.

PubMed

Teixeira, Marcella A; Rajewski, Alex; He, Jiangman; Castaneda, Olenka G; Litt, Amy; Kaloshian, Isgouhi

2018-04-06

Pathogen perception by plants is mediated by plasma membrane-localized immune receptors that have varied extracellular domains. Lectin receptor kinases (LecRKs) are among these receptors and are subdivided into 3 classes, C-type LecRKs (C-LecRKs), L-type LecRKs (L-LecRKs) and G-type LecRKs (G-LecRKs). While C-LecRKs are represented by one or two members in all plant species investigated and have unknown functions, L-LecRKs have been characterized in a few plant species and have been shown to play roles in plant defense against pathogens. Whereas Arabidopsis G-LecRKs have been characterized, this family of LecRKs has not been studied in tomato. This investigation updates the current characterization of Arabidopsis G-LecRKs and characterizes the tomato G-LecRKs, using LecRKs from the monocot rice and the basal eudicot columbine to establish a basis for comparisons between the two core eudicots. Additionally, revisiting parameters established for Arabidopsis nomenclature for LecRKs is suggested for both Arabidopsis and tomato. Moreover, using phylogenetic analysis, we show the relationship among and between members of G-LecRKs from all three eudicot plant species. Furthermore, investigating presence of motifs in G-LecRKs we identified conserved motifs among members of G-LecRKs in tomato and Arabidopsis, with five present in at least 30 of the 38 Arabidopsis members and in at least 45 of the 73 tomato members. This work characterized tomato G-LecRKs and added members to the currently characterized Arabidopsis G-LecRKs. Additionally, protein sequence analysis showed an expansion of this family in tomato as compared to Arabidopsis, and the existence of conserved common motifs in the two plant species as well as conserved species-specific motifs.

The tomato FT ortholog triggers systemic signals that regulate growth and flowering and substitute for diverse environmental stimuli

PubMed Central

Lifschitz, Eliezer; Eviatar, Tamar; Rozman, Alexander; Shalit, Akiva; Goldshmidt, Alexander; Amsellem, Ziva; Alvarez, John Paul; Eshed, Yuval

2006-01-01

The systemic model for floral induction, dubbed florigen, was conceived in photoperiod-sensitive plants but implies, in its ultimate form, a graft-transmissible signal that, although activated by different stimuli in different flowering systems, is common to all plants. We show that SFT (SINGLE-FLOWER TRUSS), the tomato ortholog of FLOWERING LOCUS T (FT), induces flowering in day-neutral tomato and tobacco plants and is encoded by SFT. sft tomato mutant plants are late-flowering, with altered architecture and flower morphology. SFT-dependent graft-transmissible signals complement all developmental defects in sft plants and substitute for long-day stimuli in Arabidopsis, short-day stimuli in Maryland Mammoth tobacco, and light-dose requirements in tomato uniflora mutant plants. The absence of donor SFT RNA from flowering receptor shoots and the localization of the protein in leaf nuclei implicate florigen-like messages in tomato as a downstream pathway triggered by cell-autonomous SFT RNA transcripts. Flowering in tomato is synonymous with termination of the shoot apical meristems, and systemic SFT messages attenuate the growth of apical meristems before and independent of floral production. Floral enhancement by systemic SFT signals is therefore one pleiotropic effect of FT orthologs. PMID:16606827

The tomato FT ortholog triggers systemic signals that regulate growth and flowering and substitute for diverse environmental stimuli.

PubMed

Lifschitz, Eliezer; Eviatar, Tamar; Rozman, Alexander; Shalit, Akiva; Goldshmidt, Alexander; Amsellem, Ziva; Alvarez, John Paul; Eshed, Yuval

2006-04-18

The systemic model for floral induction, dubbed florigen, was conceived in photoperiod-sensitive plants but implies, in its ultimate form, a graft-transmissible signal that, although activated by different stimuli in different flowering systems, is common to all plants. We show that SFT (SINGLE-FLOWER TRUSS), the tomato ortholog of FLOWERING LOCUS T (FT), induces flowering in day-neutral tomato and tobacco plants and is encoded by SFT. sft tomato mutant plants are late-flowering, with altered architecture and flower morphology. SFT-dependent graft-transmissible signals complement all developmental defects in sft plants and substitute for long-day stimuli in Arabidopsis, short-day stimuli in Maryland Mammoth tobacco, and light-dose requirements in tomato uniflora mutant plants. The absence of donor SFT RNA from flowering receptor shoots and the localization of the protein in leaf nuclei implicate florigen-like messages in tomato as a downstream pathway triggered by cell-autonomous SFT RNA transcripts. Flowering in tomato is synonymous with termination of the shoot apical meristems, and systemic SFT messages attenuate the growth of apical meristems before and independent of floral production. Floral enhancement by systemic SFT signals is therefore one pleiotropic effect of FT orthologs.

Parasite Removal, but Not Herbivory, Deters Future Parasite Attachment on Tomato

PubMed Central

Tjiurutue, Muvari Connie; Palmer-Young, Evan C.; Adler, Lynn S.

2016-01-01

Plants face many antagonistic interactions that occur sequentially. Often, plants employ defense strategies in response to the initial damage that are highly specific and can affect interactions with subsequent antagonists. In addition to herbivores and pathogens, plants face attacks by parasitic plants, but we know little about how prior herbivory compared to prior parasite attachment affects subsequent host interactions. If host plants can respond adaptively to these different damage types, we predict that prior parasitism would have a greater deterrent effect on subsequent parasites than would prior herbivory. To test the effects of prior parasitism and prior herbivory on subsequent parasitic dodder (Cuscuta spp.) preference, we conducted two separate greenhouse studies with tomato hosts (Solanum lycopersicum). In the first experiment, we tested the effects of previous dodder attachment on subsequent dodder preference on tomato hosts using three treatments: control plants that had no previous dodder attachment; dodder-removed plants that had an initial dodder seedling attached, removed and left in the same pot to simulate parasite death; and dodder-continuous plants with an initial dodder seedling that remained attached. In the second experiment, we tested the effects of previous caterpillar damage (Spodoptera exigua) and mechanical damage on future dodder attachment on tomato hosts. Dodder attached most slowly to tomato hosts that had dodder plants previously attached and then removed, compared to control plants or plants with continuous dodder attachment. In contrast, herbivory did not affect subsequent dodder attachment rate. These results indicate that dodder preference depended on the identity and the outcome of the initial attack, suggesting that early-season interactions have the potential for profound impacts on subsequent community dynamics. PMID:27529694

SlMAPK3 enhances tolerance to tomato yellow leaf curl virus (TYLCV) by regulating salicylic acid and jasmonic acid signaling in tomato (Solanum lycopersicum)

PubMed Central

Li, Yunzhou; Qin, Lei; Zhao, Jingjing; Muhammad, Tayeb; Cao, Hehe; Li, Hailiang; Zhang, Yan; Liang, Yan

2017-01-01

Several recent studies have reported on the role of mitogen-activated protein kinase (MAPK3) in plant immune responses. However, little is known about how MAPK3 functions in tomato (Solanum lycopersicum L.) infected with tomato yellow leaf curl virus (TYLCV). There is also uncertainty about the connection between plant MAPK3 and the salicylic acid (SA) and jasmonic acid (JA) defense-signaling pathways. The results of this study indicated that SlMAPK3 participates in the antiviral response against TYLCV. Tomato seedlings were inoculated with TYLCV to investigate the possible roles of SlMAPK1, SlMAPK2, and SlMAPK3 against this virus. Inoculation with TYLCV strongly induced the expression and the activity of all three genes. Silencing of SlMAPK1, SlMAPK2, and SlMAPK3 reduced tolerance to TYLCV, increased leaf H2O2 concentrations, and attenuated expression of defense-related genes after TYLCV infection, especially in SlMAPK3-silenced plants. Exogenous SA and methyl jasmonic acid (MeJA) both significantly induced SlMAPK3 expression in tomato leaves. Over-expression of SlMAPK3 increased the transcript levels of SA/JA-mediated defense-related genes (PR1, PR1b/SlLapA, SlPI-I, and SlPI-II) and enhanced tolerance to TYLCV. After TYLCV inoculation, the leaves of SlMAPK3 over-expressed plants compared with wild type plants showed less H2O2 accumulation and greater superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) activity. Overall, the results suggested that SlMAPK3 participates in the antiviral response of tomato to TYLCV, and that this process may be through either the SA or JA defense-signaling pathways. PMID:28222174

SlMAPK3 enhances tolerance to tomato yellow leaf curl virus (TYLCV) by regulating salicylic acid and jasmonic acid signaling in tomato (Solanum lycopersicum).

PubMed

Li, Yunzhou; Qin, Lei; Zhao, Jingjing; Muhammad, Tayeb; Cao, Hehe; Li, Hailiang; Zhang, Yan; Liang, Yan

2017-01-01

Several recent studies have reported on the role of mitogen-activated protein kinase (MAPK3) in plant immune responses. However, little is known about how MAPK3 functions in tomato (Solanum lycopersicum L.) infected with tomato yellow leaf curl virus (TYLCV). There is also uncertainty about the connection between plant MAPK3 and the salicylic acid (SA) and jasmonic acid (JA) defense-signaling pathways. The results of this study indicated that SlMAPK3 participates in the antiviral response against TYLCV. Tomato seedlings were inoculated with TYLCV to investigate the possible roles of SlMAPK1, SlMAPK2, and SlMAPK3 against this virus. Inoculation with TYLCV strongly induced the expression and the activity of all three genes. Silencing of SlMAPK1, SlMAPK2, and SlMAPK3 reduced tolerance to TYLCV, increased leaf H2O2 concentrations, and attenuated expression of defense-related genes after TYLCV infection, especially in SlMAPK3-silenced plants. Exogenous SA and methyl jasmonic acid (MeJA) both significantly induced SlMAPK3 expression in tomato leaves. Over-expression of SlMAPK3 increased the transcript levels of SA/JA-mediated defense-related genes (PR1, PR1b/SlLapA, SlPI-I, and SlPI-II) and enhanced tolerance to TYLCV. After TYLCV inoculation, the leaves of SlMAPK3 over-expressed plants compared with wild type plants showed less H2O2 accumulation and greater superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) activity. Overall, the results suggested that SlMAPK3 participates in the antiviral response of tomato to TYLCV, and that this process may be through either the SA or JA defense-signaling pathways.

Salmonella Persistence in Tomatoes Requires a Distinct Set of Metabolic Functions Identified by Transposon Insertion Sequencing.

PubMed

de Moraes, Marcos H; Desai, Prerak; Porwollik, Steffen; Canals, Rocio; Perez, Daniel R; Chu, Weiping; McClelland, Michael; Teplitski, Max

2017-03-01

Human enteric pathogens, such as Salmonella spp. and verotoxigenic Escherichia coli , are increasingly recognized as causes of gastroenteritis outbreaks associated with the consumption of fruits and vegetables. Persistence in plants represents an important part of the life cycle of these pathogens. The identification of the full complement of Salmonella genes involved in the colonization of the model plant (tomato) was carried out using transposon insertion sequencing analysis. With this approach, 230,000 transposon insertions were screened in tomato pericarps to identify loci with reduction in fitness, followed by validation of the screen results using competition assays of the isogenic mutants against the wild type. A comparison with studies in animals revealed a distinct plant-associated set of genes, which only partially overlaps with the genes required to elicit disease in animals. De novo biosynthesis of amino acids was critical to persistence within tomatoes, while amino acid scavenging was prevalent in animal infections. Fitness reduction of the Salmonella amino acid synthesis mutants was generally more severe in the tomato rin mutant, which hyperaccumulates certain amino acids, suggesting that these nutrients remain unavailable to Salmonella spp. within plants. Salmonella lipopolysaccharide (LPS) was required for persistence in both animals and plants, exemplifying some shared pathogenesis-related mechanisms in animal and plant hosts. Similarly to phytopathogens, Salmonella spp. required biosynthesis of amino acids, LPS, and nucleotides to colonize tomatoes. Overall, however, it appears that while Salmonella shares some strategies with phytopathogens and taps into its animal virulence-related functions, colonization of tomatoes represents a distinct strategy, highlighting this pathogen's flexible metabolism. IMPORTANCE Outbreaks of gastroenteritis caused by human pathogens have been increasingly associated with foods of plant origin, with tomatoes being

Salmonella Persistence in Tomatoes Requires a Distinct Set of Metabolic Functions Identified by Transposon Insertion Sequencing

PubMed Central

Desai, Prerak; Porwollik, Steffen; Canals, Rocio; Perez, Daniel R.; Chu, Weiping; McClelland, Michael; Teplitski, Max

2016-01-01

ABSTRACT Human enteric pathogens, such as Salmonella spp. and verotoxigenic Escherichia coli, are increasingly recognized as causes of gastroenteritis outbreaks associated with the consumption of fruits and vegetables. Persistence in plants represents an important part of the life cycle of these pathogens. The identification of the full complement of Salmonella genes involved in the colonization of the model plant (tomato) was carried out using transposon insertion sequencing analysis. With this approach, 230,000 transposon insertions were screened in tomato pericarps to identify loci with reduction in fitness, followed by validation of the screen results using competition assays of the isogenic mutants against the wild type. A comparison with studies in animals revealed a distinct plant-associated set of genes, which only partially overlaps with the genes required to elicit disease in animals. De novo biosynthesis of amino acids was critical to persistence within tomatoes, while amino acid scavenging was prevalent in animal infections. Fitness reduction of the Salmonella amino acid synthesis mutants was generally more severe in the tomato rin mutant, which hyperaccumulates certain amino acids, suggesting that these nutrients remain unavailable to Salmonella spp. within plants. Salmonella lipopolysaccharide (LPS) was required for persistence in both animals and plants, exemplifying some shared pathogenesis-related mechanisms in animal and plant hosts. Similarly to phytopathogens, Salmonella spp. required biosynthesis of amino acids, LPS, and nucleotides to colonize tomatoes. Overall, however, it appears that while Salmonella shares some strategies with phytopathogens and taps into its animal virulence-related functions, colonization of tomatoes represents a distinct strategy, highlighting this pathogen's flexible metabolism. IMPORTANCE Outbreaks of gastroenteritis caused by human pathogens have been increasingly associated with foods of plant origin, with tomatoes

Guidelines to use tomato in experiments with a controlled environment

PubMed Central

Schwarz, Dietmar; Thompson, Andrew J.; Kläring, Hans-Peter

2014-01-01

Domesticated tomato (Solanum lycopersicum) is the most important horticultural crop worldwide. Low polymorphism at the DNA level conflicts with the wealth of morphological variation. Fruits vary widely in size, shape, and color. In contrast, genetic variation between the 16 wild relatives is tremendous. Several large seed banks provide tomato germplasm for both domesticated and wild accessions of tomato. Recently, the genomes of the inbred cultivar “Heinz 1706” (≈900 Mb), and S. pimpinellifolium (739 Mb) were sequenced. Genomic markers and genome re-sequencing data are available for >150 cultivars and accessions. Transformation of tomato is relatively easy and T-DNA insertion line collections are available. Tomato is widely used as a model crop for fruit development but also for diverse physiological, cellular, biochemical, molecular, and genetic studies. It can be easily grown in greenhouses or growth chambers. Plants grow, flower, and develop fruits well at daily light lengths between 8 and 16 h. The required daily light integral of an experiment depends on growth stage and temperature investigated. Temperature must be 10–35°C, relative humidity 30–90%, and, CO2 concentration 200–1500 μmol mol−1. Temperature determines the speed of the phenological development while daily light integral and CO2 concentration affect photosynthesis and biomass production. Seed to seed cultivation takes 100 days at 20°C and can be shortened or delayed by temperature. Tomato may be cultivated in soil, substrates, or aeroponically without any substrate. Root volume, and water uptake requirements are primarily determined by transpiration demands of the plants. Many nutrient supply recipes and strategies are available to ensure sufficient supply as well as specific nutrient deficits/surplus. Using appropriate cultivation techniques makes tomato a convenient model plant for researchers, even for beginners. PMID:25477888

Molecular cloning and characterization of a novel tomato xylosyltransferase specific for gentisic acid.

PubMed

Tárraga, Susana; Lisón, Purificación; López-Gresa, María Pilar; Torres, Cristina; Rodrigo, Ismael; Bellés, José María; Conejero, Vicente

2010-10-01

The importance of salicylic acid (SA) in the signal transduction pathway of plant disease resistance has been well documented in many incompatible plant-pathogen interactions, but less is known about signalling in compatible interactions. In this type of interaction, tomato plants have been found to accumulate high levels of 2,5-dihydroxybenzoic acid (gentisic acid, GA), a metabolic derivative of SA. Exogenous GA treatments induce in tomato plants a set of PR proteins that differ from those induced by salicylic acid. While SA accumulates in tomato plants mainly as 2-O-β-D-glucoside, GA has only been found as 5-O-β-D-xyloside. To characterize this step of the GA signalling pathway further, the present work focuses on the study of the GA-conjugating activity in tomato plants. A gentisate glycosyltransferase (GAGT) cDNA has been isolated and overexpressed in Pichia pastoris, and GA-conjugating activity was confirmed by detecting the xylosylated GA. The purified plant protein is highly specific for GA, showing no activity toward many other phenolic compounds, including SA. In addition, it shows an outstanding selectivity for UDP-xylose as the sugar donor, which differentiates this enzyme from most glycosyltransferases. Both the GA-conjugating activity and the corresponding mRNA show a strong, rapid, and transient induction upon treatment of tomato plants with GA or SA. Furthermore, its expression is rapidly induced by compatible infections. However, neither the gene nor the activity seems to respond to incompatible infections or wounding. The unique properties of this new glycosyltransferase suggest a specific role in regulating the free GA levels in compatible plant-pathogen interactions.

Pharmacological and gene regulation properties point to the SlHAK5 K+ transporter as a system for high-affinity Cs+ uptake in tomato plants.

PubMed

Ródenas, Reyes; Nieves-Cordones, Manuel; Rivero, Rosa M; Martinez, Vicente; Rubio, Francisco

2018-04-01

Potassium (K + ) and cesium (Cs + ) are chemically similar but while K + is an essential nutrient, Cs + can be toxic for living organisms, plants included. Two different situations could lead to problems derived from the presence of Cs + in agricultural systems: (1) presence of Cs + at high concentrations that could produce toxic effects on plants, (2) presence of micromolar concentrations of radiocesium, which can be accumulated in the plant and affect animal and human health through the food chain. While K + uptake has been well described in tomato plants, information on molecular mechanisms involved in Cs + accumulation in this species is absent. Here, we show that in tomato plants, high concentrations of Cs + produce deficiency of K + but do not induce high-affinity K + uptake or the gene encoding the high-affinity K + transporter SlHAK5. At these concentrations, Cs + uptake takes place through a Ca 2+ -sensitive pathway, probably a non-selective cation channel. At micromolar concentrations, Cs + is accumulated by a high-affinity uptake system upregulated in K + -starved plants. This high-affinity Cs + uptake shares features with high-affinity K + uptake. It is sensitive to NH 4 + and insensitive to Ba 2+ and Ca 2+ and its presence parallels the pattern of SlHAK5 expression. Moreover, blockers of reactive oxygen species and ethylene action repress SlHAK5 and negatively regulate both high-affinity K + and Cs + uptake. Thus, we propose that SlHAK5 contributes to Cs + uptake from micromolar concentrations in tomato plants and can constitute a pathway for radiocesium transfer from contaminated areas to the food chain. © 2017 Scandinavian Plant Physiology Society.

A plant derived multifunctional tool for nanobiotechnology based on Tomato bushy stunt virus.

PubMed

Grasso, Simone; Lico, Chiara; Imperatori, Francesca; Santi, Luca

2013-06-01

Structure, size, physicochemical properties and production strategies make many plant viruses ideal protein based nanoscaffolds, nanocontainers and nano-building blocks expected to deliver a multitude of applications in different fields such as biomedicine, pharmaceutical chemistry, separation science, catalytic chemistry, crop pest control and biomaterials science. Functionalization of viral nanoparticles through modification by design of their external and internal surfaces is essential to fully exploit the potentiality of these objects. In the present paper we describe the development of a plant derived multifunctional tool for nanobiotechnology based on Tomato bushy stunt virus. We demonstrate the ability of this system to remarkably sustain genetic modifications and in vitro chemical derivatizations of its outer surface, which resulted in the successful display of large chimeric peptides fusions and small chemical molecules, respectively. Moreover, we have defined physicochemical conditions for viral swelling and reversible viral pore gating that we have successfully employed for foreign molecules loading and retention in the inner cavity of this plant virus nanoparticles system. Finally, a production and purification strategy from Nicotiana benthamiana plants has been addressed and optimized.

A Primary Screening and Applying of Plant Volatiles as Repellents to Control Whitefly Bemisia tabaci (Gennadius) on Tomato

NASA Astrophysics Data System (ADS)

Du, Wenxiao; Han, Xiaoqing; Wang, Yubo; Qin, Yuchuan

2016-02-01

With the goal of finding a new way to reduce population densities of Bemisia tabaci biotype Q in greenhouses, seven repellent volatile chemicals and their combinations were screened. The mixture of DLCO (D-limonene, citral and olive oil (63:7:30)) had a better cost performance(SC50 = 22.59 mg/ml)to repel whiteflies from settling than the other mixtures or single chemicals. In the greenhouse, in both the choice test and the no-choice tests, the number of adult whiteflies that settled on 1% DLCO-treated tomato plants was significantly lower than those settling on the control plants for the different exposure periods (P < 0.01). In the choice test, the egg amount on the treated tomato plants was significantly lower (P < 0.01) than that on the control plants, but there was no significant difference (P > 0.05) between the number of eggs on treated and control plants in the no-choice test. Compared with the controls, 1% DLCO did not cause significantly statistic mortality rates (P > 0.05) out of different living stages of B. tabaci. The tests for evaluating the repellent efficacy, showed that a slow-releasing bottle containing the mixture had a period of efficacy of 29 days, and the application of this mixture plus a yellow board used as a push-pull strategy in the greenhouse was also effective.

A Primary Screening and Applying of Plant Volatiles as Repellents to Control Whitefly Bemisia tabaci (Gennadius) on Tomato

PubMed Central

Du, Wenxiao; Han, Xiaoqing; Wang, Yubo; Qin, Yuchuan

2016-01-01

With the goal of finding a new way to reduce population densities of Bemisia tabaci biotype Q in greenhouses, seven repellent volatile chemicals and their combinations were screened. The mixture of DLCO (D-limonene, citral and olive oil (63:7:30)) had a better cost performance(SC50 = 22.59 mg/ml)to repel whiteflies from settling than the other mixtures or single chemicals. In the greenhouse, in both the choice test and the no-choice tests, the number of adult whiteflies that settled on 1% DLCO-treated tomato plants was significantly lower than those settling on the control plants for the different exposure periods (P < 0.01). In the choice test, the egg amount on the treated tomato plants was significantly lower (P < 0.01) than that on the control plants, but there was no significant difference (P > 0.05) between the number of eggs on treated and control plants in the no-choice test. Compared with the controls, 1% DLCO did not cause significantly statistic mortality rates (P > 0.05) out of different living stages of B. tabaci. The tests for evaluating the repellent efficacy, showed that a slow-releasing bottle containing the mixture had a period of efficacy of 29 days, and the application of this mixture plus a yellow board used as a push-pull strategy in the greenhouse was also effective. PMID:26907368

Organogenesis from transformed tomato explants.

PubMed

Frary, Anne; Van Eck, Joyce

2005-01-01

Tomato was one of the first crops for which a genetic transformation system was reported involving regeneration by organogenesis from Agrobacterium-transformed explants. Since the initial reports, various factors have been studied that affect the efficiency of tomato transformation and the technique has been useful for the isolation and identification of many genes involved in plant disease resistance, morphology and development. In this method, cotyledon explants from in vitro-grown seedlings are precultured overnight on a tobacco suspension feeder layer. The explants are then inoculated with Agrobacterium and returned to the feeder layer for a 2-d period of cocultivation. After cocultivation, the explants are transferred to an MS-based selective regeneration medium containing zeatin. Regenerated shoots are then rooted on a separate selective medium. This protocol has been used with several tomato cultivars and routinely yields transformation efficiencies of 10-15%.

Release of lipoxygenase products and monoterpenes by tomato plants as an indicator of Botrytis cinerea-induced stress.

PubMed

Jansen, R M C; Miebach, M; Kleist, E; van Henten, E J; Wildt, J

2009-11-01

Changes in emission of volatile organic compounds (VOCs) from tomato induced by the fungus Botrytis cinerea were studied in plants inoculated by spraying with suspensions containing B. cinerea spores. VOC emissions were analysed using on-line gas chromatography-mass spectrometry, with a time resolution of about 1 h, for up to 2 days after spraying. Four phases were delimited according to the starting point and the applied day/night rhythm of the experiments. These phases were used to demonstrate changes in VOC flux caused by B. cinerea infestation. Tomato plants inoculated with B. cinerea emitted a different number and amount of VOCs after inoculation compared to control plants that had been sprayed with a suspension without B. cinerea spores. The changes in emissions were dependent on time after inoculation as well as on the severity of infection. The predominant VOCs emitted after inoculation were volatile products from the lipoxygenase pathway (LOX products). The increased emission of LOX products proved to be a strong indicator of a stress response, indicating that VOC emissions can be used to detect plant stress at an early stage. Besides emission of LOX products, there were also increases in monoterpene emissions. However, neither increased emission of LOX products nor of monoterpenes is specific for B. cinerea attack. The emission of LOX products is also induced by other stresses, and increased emission of monoterpenes seems to be the result of mechanical damage induced by secondary stress impacts on leaves.

Effect of a formulation of Bacillus firmus on root-knot nematode Meloidogyne incognita infestation and the growth of tomato plants in the greenhouse and nursery.

PubMed

Terefe, Metasebia; Tefera, Tadele; Sakhuja, P K

2009-02-01

Bacillus firmus, commercial WP formulation (BioNem) was evaluated against the root-knot nematode Meloidogyne incognita in a laboratory, greenhouse and under field conditions on tomato plants. In the laboratory tests, an aqueous suspension of BioNem at 0.5%, 1%, 1.5% and 2% concentration reduced egg hatching from 98% to 100%, 24-days after treatment. Treatment of second-stage juveniles with 2.5% and 3% concentration of BioNem, caused 100% inhibition of mobility, 24 h after treatment. In the green house trials, BioNem applied at 8 g/pot (1200 cc soil) planted with a tomato seedlings reduced gall formation by 91%, final nematode populations by 76% and the number of eggs by 45%. Consequently, plant height and biomass was increased by 71% and 50%, respectively, compared to the untreated control, 50-days after treatment application. Application of BioNem at 16 g/pot was phytotoxic to plants. In the field trails, BioNem applied at 200 and 400 kg ha(-1) was effective in reducing the number of galls (75-84%), and increased shoot height (29-31%) and weight (20-24%) over the untreated control, 45-days after treatment. Our results indicate that B. firmus is a promising microorganism for the biological control of M. incognita in tomato pots.

Analysis of tomato gene promoters activated in syncytia induced in tomato and potato hairy roots by Globodera rostochiensis.

PubMed

Wiśniewska, A; Dąbrowska-Bronk, J; Szafrański, K; Fudali, S; Święcicka, M; Czarny, M; Wilkowska, A; Morgiewicz, K; Matusiak, J; Sobczak, M; Filipecki, M

2013-06-01

The potato cyst nematode (Globodera rostochiensis) induces feeding sites (syncytia) in tomato and potato roots. In a previous study, 135 tomato genes up-regulated during G. rostochiensis migration and syncytium development were identified. Five genes (CYP97A29, DFR, FLS, NIK and PMEI) were chosen for further study to examine their roles in plant-nematode interactions. The promoters of these genes were isolated and potential cis regulatory elements in their sequences were characterized using bioinformatics tools. Promoter fusions with the β-glucuronidase gene were constructed and introduced into tomato and potato genomes via transformation with Agrobacterium rhizogenes to produce hairy roots. The analysed promoters displayed different activity patterns in nematode-infected and uninfected transgenic hairy roots.

Prospects: the tomato genome as a cornerstone for gene discovery

USDA-ARS?s Scientific Manuscript database

Those involved in the international tomato genome sequencing effort contributed to not only the development of an important genome sequence relevant to a major economic and nutritional crop, but also to the tomato experimental system as a model for plant biology. Without question, prior seminal work...

Multidisciplinary approach to assess the sensitivity of dwarf tomato plants to low-LET ionising radiation

NASA Astrophysics Data System (ADS)

De Micco, Veronica; De Pascale, Stefania; Aronne, Giovanna; Paradiso, Roberta; Vitaglione, Paola; Turano, Mimmo; Arena, Carmen

Ionising radiation, acting alone or in interaction with microgravity and other environmental constraints, may affect plant at molecular, morpho-structural and physiological level. The intensity of the plant’s response depends on the properties of radiation and on the features of the plant itself. Indeed, different species are characterised by different susceptibility to radiation which may change during the life course. The aim of this research was to study the radiosensitivity to low-LET ionising radiation of plants of dwarf tomato (Solanum lycopersicum L. ‘Microtom’) at two phenological phases (vegetative and reproductive), within the purpose of analysing plants for consideration as candidates for Bioregenerative Life Support Systems (BLSS) in Space. To pursue this objective, plants of the cultivar Microtom were irradiated with different doses of X-rays either at the stage of the second true leaf (VP - vegetative phase) or when at least one flower was blossomed (RP - reproductive phase). Plant’s response to ionising radiation was assessed through a multidisciplinary approach combining genetic analyses, ecophysiological measurements, morpho-anatomical characterisation of leaves and fruits, nutritional analyses of fruits. Growth, molecular and morpho-functional traits were measured during plant development up to fruiting in both VP and RP plant groups, and compared with non-irradiated control plants. Plant growth was monitored weekly recording parameters such as plant height, number of leaves, leaf area, flowering and fruiting rate. Potential DNA alterations were explored through Random Amplified Polymorphic DNA (RAPD) technique. The efficiency of the photosynthetic apparatus was evaluated by determining photosynthetic pigment composition, photochemistry and leaf gas exchanges. Leaf and fruit structure were analysed through light and epi-fluorescence microscopy. Leaf anatomical traits related to photosynthetic efficiency, and to structural radioprotection

Cholera toxin B protein in transgenic tomato fruit induces systemic immune response in mice.

PubMed

Jiang, Xiao-Ling; He, Zhu-Mei; Peng, Zhi-Qiang; Qi, Yu; Chen, Qing; Yu, Shou-Yi

2007-04-01

Cholera toxin B (CTB) subunit is a well-characterized antigen against cholera. Transgenic plants can offer an inexpensive and safe source of edible CTB vaccine and may be one of the best candidates for the production of plant vaccines. The present study aimed to develop transgenic tomato expressing CTB protein, especially in the ripening tomato fruit under the control of the tomato fruit-specific E8 promoter by using Agrobacterium-mediated transformation. Transgenic plants were selected using PCR and Southern blot analysis. Exogenous protein extracted from leaf, stem, and fruit tissues of transgenic plants was detected by ELISA and Western blot analysis, showing specific expression in the ripening fruit, with the highest amount of CTB protein being 0.081% of total soluble protein. Gavage of mice with ripe transgenic tomato fruits induced both serum and mucosal CTB specific antibodies. These results demonstrate the immunogenicity of the CTB protein in transgenic tomato and provide a considerable basis for exploring the utilization of CTB in the development of tomato-based edible vaccine against cholera. The rCTB antigen resulted in much lower antibody titers than an equal amount of exogenous CTB in transgenic fruits, suggesting the protective effect of the fibrous tissue of the fruit to the exogenous CTB protein against the degradation of protease in the digestive tracts of mice.

Rhizosphere Microbiomes Modulated by Pre-crops Assisted Plants in Defense Against Plant-Parasitic Nematodes

PubMed Central

Elhady, Ahmed; Adss, Shimaa; Hallmann, Johannes; Heuer, Holger

2018-01-01

Plant-parasitic nematodes cause considerable damage to crop plants. The rhizosphere microbiome can affect invasion and reproductive success of plant-parasitic nematodes, thus affecting plant damage. In this study, we investigated how the transplanted rhizosphere microbiome from different crops affect plant-parasitic nematodes on soybean or tomato, and whether the plant’s own microbiome from the rhizosphere protects it better than the microbiome from fallow soil. Soybean plants growing in sterilized substrate were inoculated with the microbiome extracted from the rhizosphere of soybean, maize, or tomato. Controls were inoculated with extracts from bulk soil, or not inoculated. After the microbiome was established, the root lesion nematode Pratylenchus penetrans was added. Root invasion of P. penetrans was significantly reduced on soybean plants inoculated with the microbiome from maize or soybean compared to tomato or bulk soil, or the uninoculated control. In the analogous experiment with tomato plants inoculated with either P. penetrans or the root knot nematode Meloidogyne incognita, the rhizosphere microbiomes of maize and tomato reduced root invasion by P. penetrans and M. incognita compared to microbiomes from soybean or bulk soil. Reproduction of M. incognita on tomato followed the same trend, and it was best suppressed by the tomato rhizosphere microbiome. In split-root experiments with soybean and tomato plants, a systemic effect of the inoculated rhizosphere microbiomes on root invasion of P. penetrans was shown. Furthermore, some transplanted microbiomes slightly enhanced plant growth compared to uninoculated plants. The microbiomes from maize rhizosphere and bulk soil increased the fresh weights of roots and shoots of soybean plants, and microbiomes from soybean rhizosphere and bulk soil increased the fresh weights of roots and shoots of tomato plants. Nematode invasion did not affect plant growth in these short-term experiments. In conclusion, this

Evaluating Weeds as Hosts of Tomato yellow leaf curl virus.

PubMed

Smith, Hugh A; Seijo, Teresa E; Vallad, Gary E; Peres, Natalia A; Druffel, Keri L

2015-08-01

Bemisia tabaci (Gennadius) biotype B transmits Tomato yellow leaf curl virus (TYLCV), which affects tomato production globally. Prompt destruction of virus reservoirs is a key component of virus management. Identification of weed hosts of TYLCV will be useful for reducing such reservoirs. The status of weeds as alternate hosts of TYLCV in Florida remains unclear. In greenhouse studies, B. tabaci adults from a colony reared on TYLCV-infected tomato were established in cages containing one of four weeds common to horticultural fields in central and south Florida. Cages containing tomato and cotton were also infested with viruliferous whiteflies as a positive control and negative control, respectively. Whitefly adults and plant tissue were tested periodically over 10 wk for the presence of TYLCV using PCR. After 10 wk, virus-susceptible tomato plants were placed in each cage to determine if whiteflies descended from the original adults were still infective. Results indicate that Bidens alba, Emilia fosbergii, and Raphanus raphanistrum are not hosts of TYLCV, and that Amaranthus retroflexus is a host. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Elevated O3 increases volatile organic compounds via jasmonic acid pathway that promote the preference of parasitoid Encarsia formosa for tomato plants.

PubMed

Cui, Hongying; Wei, Jianing; Su, Jianwei; Li, Chuanyou; Ge, Feng

2016-12-01

The elevated atmospheric O 3 level may change the interactions of plants and insects, which potentially affects direct and indirect plant defences. However, the underlying mechanism of the impact of elevated O 3 on indirect plant defence, namely the efficacy of natural enemies, is unclear. Here we tested a hypothesis that linked the effects of elevated O 3 and whitefly herbivory on tomato volatile releases mediated by the jasmonic acid (JA) pathway with the preferences of parasitoid Encarsia formosa for two different tomato genotypes (wild-type (Wt) and JA-deficient genotype (spr2)). The O 3 and whitefly herbivory significantly increased the production of volatile organic compounds (VOCs), including monoterpenes and green leaf volatiles (GLVs). The Wt plants released higher volatile levels, particularly monoterpenes, than did the spr2 plants. In Y-tube tests, limonene and Z-3-hexanol played key roles in the attraction of E. formosa. Moreover, regardless of plant genotype, the two plant genotypes were preferred by adult E. formosa under the O 3 and O 3 + herbivory treatments. Our results suggest that under elevated O 3 , the activation of the JA pathway significantly up-regulates the emission rates of volatiles, through which the efficacy of natural enemy might be promoted. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Enhancement of growth and yield of tomato by Rhodopseudomonas sp. under greenhouse conditions.

PubMed

Lee, Kang-Hyeong; Koh, Rae-Hyun; Song, Hong-Gyu

2008-12-01

A greenhouse test was carried out to examine the effects on tomato growth of application of purple non-sulfur bacterium Rhodopseudomonas sp. which had enhanced germination and growth of tomato seed under axenic conditions. The shoot length of tomato plant inoculated by Rhodopseudomonas sp. KL9 increased by 34.6% compared to that of control in 8 weeks of cultivation. During the same period, this strain increased 120.6 and 78.6% of dry weight of shoot and root of tomato plants, respectively. The formation ratio of tomato fruit from flower was also raised by inoculation of KL9. In addition, Rhodopseudomonas sp. KL9 treatment enhanced the fresh weight and lycopene content in the harvested tomato fruits by 98.3 and 48.3%, respectively compared to those of the uninoculated control. When the effect on the indigenous bacterial community and fate of the inoculated Rhodopseudomonas sp. KL9 were monitored by denaturing gradient gel electrophoresis analysis, its application did not affect the native bacterial community in tomato rhizosphere soil, but should be repeated to maintain its population size. This bacterial capability may be applied as an environment-friendly biofertilizer to cultivation of high quality tomato and other crops including lycopene-containing vegetables and fruits.

The typical RB76 recombination breakpoint of the invasive recombinant tomato yellow leaf curl virus of Morocco can be generated experimentally but is not positively selected in tomato.

PubMed

Belabess, Z; Urbino, C; Granier, M; Tahiri, A; Blenzar, A; Peterschmitt, M

2018-01-02

TYLCV-IS76 is an unusual recombinant between the highly recombinogenic tomato yellow leaf curl virus (TYLCV) and tomato yellow leaf curl Sardinia virus (TYLCSV), two Mediterranean begomoviruses (Geminiviridae). In contrast with the previously reported TYLCV/TYLCSV recombinants, it has a TYLCSV derived fragment of only 76 nucleotides, and has replaced its parental viruses in natural conditions (Morocco, Souss region). The viral population shift coincided with the deployment of the popular Ty-1 resistant tomato cultivars, and according to experimental studies, has been driven by a strong positive selection in such resistant plants. However, although Ty-1 cultivars were extensively used in Mediterranean countries, TYLCV-IS76 was not reported outside Morocco. This, in combination with its unusual recombination pattern suggests that it was generated through a rare and possibly multistep process. The potential generation of a recombination breakpoint (RB) at locus 76 (RB76) was investigated over time in 10 Ty-1 resistant and 10 nearly isogenic susceptible tomato plants co-inoculated with TYLCV and TYLCSV clones. RB76 could not be detected in the recombinant progeny using the standard PCR/sequencing approach that was previously designed to monitor the emergence of TYLCV-IS76 in Morocco. Using a more sensitive PCR test, RB76 was detected in one resistant and five susceptible plants. The results are consistent with a very low intra-plant frequency of RB76 bearing recombinants throughout the test and support the hypothesis of a rare emergence of TYLCV-IS76. More generally, RBs were more scattered in resistant than in susceptible plants and an unusual RB at position 141 (RB141) was positively selected in the resistant cultivar; interestingly, RB141 bearing recombinants were detected in resistant tomato plants from the field. Scenarios of TYLCV-IS76 pre-emergence are proposed. Copyright © 2017 Elsevier B.V. All rights reserved.

Beyond Predation: The Zoophytophagous Predator Macrolophus pygmaeus Induces Tomato Resistance against Spider Mites

PubMed Central

Pappas, Maria L.; Steppuhn, Anke; Geuss, Daniel; Topalidou, Nikoleta; Zografou, Aliki; Broufas, George D.

2015-01-01

Many predatory insects that prey on herbivores also feed on the plant, but it is unknown whether plants affect the performance of herbivores by responding to this phytophagy with defence induction. We investigate whether the prior presence of the omnivorous predator Macrolophus pygmaeus (Rambur) on tomato plants affects plant resistance against two different herbivore species. Besides plant-mediated effects of M. pygmaeus on herbivore performance, we examined whether a plant defence trait that is known to be inducible by herbivory, proteinase inhibitors (PI), may also be activated in response to the interactions of this predator with the tomato plant. We show that exposing tomato plants to the omnivorous predator M. pygmaeus reduced performance of a subsequently infesting herbivore, the two-spotted spider mite Tetranychus urticae Koch, but not of the greenhouse whitefly Trialeurodes vaporariorum (Westwood). The spider-mite infested tomato plants experience a lower herbivore load, i.e., number of eggs deposited and individuals present, when previously exposed to the zoophytophagous predator. This effect is not restricted to the exposed leaf and persists on exposed plants for at least two weeks after the removal of the predators. The decreased performance of spider mites as a result of prior exposure of the plant to M. pygmaeus is accompanied by a locally and systemically increased accumulation of transcripts and activity of proteinase inhibitors that are known to be involved in plant defence. Our results demonstrate that zoophytophagous predators can induce plant defence responses and reduce herbivore performance. Hence, the suppression of populations of certain herbivores via consumption may be strengthened by the induction of plant defences by zoophytophagous predators. PMID:25974207

Newly discovered natural hosts of tomato chlorosis virus in Costa Rica

USDA-ARS?s Scientific Manuscript database

Tomato chlorosis virus (ToCV) is an emerging whitefly-transmitted crinivirus. ToCV was detected in field-grown and greenhouse tomato (Solanum lycopersicum L.) plants in Costa Rica in 2007, causing symptoms of severe yellowing and foliar chlorosis. To identify alternative hosts that may serve as viru...

Data on xylem sap proteins from Mn- and Fe-deficient tomato plants obtained using shotgun proteomics.

PubMed

Ceballos-Laita, Laura; Gutierrez-Carbonell, Elain; Takahashi, Daisuke; Abadía, Anunciación; Uemura, Matsuo; Abadía, Javier; López-Millán, Ana Flor

2018-04-01

This article contains consolidated proteomic data obtained from xylem sap collected from tomato plants grown in Fe- and Mn-sufficient control, as well as Fe-deficient and Mn-deficient conditions. Data presented here cover proteins identified and quantified by shotgun proteomics and Progenesis LC-MS analyses: proteins identified with at least two peptides and showing changes statistically significant (ANOVA; p ≤ 0.05) and above a biologically relevant selected threshold (fold ≥ 2) between treatments are listed. The comparison between Fe-deficient, Mn-deficient and control xylem sap samples using a multivariate statistical data analysis (Principal Component Analysis, PCA) is also included. Data included in this article are discussed in depth in the research article entitled "Effects of Fe and Mn deficiencies on the protein profiles of tomato ( Solanum lycopersicum) xylem sap as revealed by shotgun analyses" [1]. This dataset is made available to support the cited study as well to extend analyses at a later stage.

Optical Sensing to Determine Tomato Plant Spacing for Precise Agrochemical Application: Two Scenarios

PubMed Central

Martínez-Guanter, Jorge; Garrido-Izard, Miguel; Valero, Constantino; Slaughter, David C.; Pérez-Ruiz, Manuel

2017-01-01

The feasibility of automated individual crop plant care in vegetable crop fields has increased, resulting in improved efficiency and economic benefits. A systems-based approach is a key feature in the engineering design of mechanization that incorporates precision sensing techniques. The objective of this study was to design new sensing capabilities to measure crop plant spacing under different test conditions (California, USA and Andalucía, Spain). For this study, three different types of optical sensors were used: an optical light-beam sensor (880 nm), a Light Detection and Ranging (LiDAR) sensor (905 nm), and an RGB camera. Field trials were conducted on newly transplanted tomato plants, using an encoder as a local reference system. Test results achieved a 98% accuracy in detection using light-beam sensors while a 96% accuracy on plant detections was achieved in the best of replications using LiDAR. These results can contribute to the decision-making regarding the use of these sensors by machinery manufacturers. This could lead to an advance in the physical or chemical weed control on row crops, allowing significant reductions or even elimination of hand-weeding tasks. PMID:28492504

Alleviation of salt stress by enterobacter sp. EJ01 in tomato and Arabidopsis is accompanied by up-regulation of conserved salinity responsive factors in plants.

PubMed

Kim, Kangmin; Jang, Ye-Jin; Lee, Sang-Myeong; Oh, Byung-Taek; Chae, Jong-Chan; Lee, Kui-Jae

2014-02-01

Microbiota in the niches of the rhizosphere zones can affect plant growth and responses to environmental stress conditions via mutualistic interactions with host plants. Specifically, some beneficial bacteria, collectively referred to as Plant Growth Promoting Rhizobacteria (PGPRs), increase plant biomass and innate immunity potential. Here, we report that Enterobacter sp. EJ01, a bacterium isolated from sea china pink (Dianthus japonicus thunb) in reclaimed land of Gyehwa-do in Korea, improved the vegetative growth and alleviated salt stress in tomato and Arabidopsis. EJ01 was capable of producing 1-aminocy-clopropane-1-carboxylate (ACC) deaminase and also exhibited indole-3-acetic acid (IAA) production. The isolate EJ01 conferred increases in fresh weight, dry weight, and plant height of tomato and Arabidopsis under both normal and high salinity conditions. At the molecular level, short-term treatment with EJ01 increased the expression of salt stress responsive genes such as DREB2b, RD29A, RD29B, and RAB18 in Arabidopsis. The expression of proline biosynthetic genes (i.e. P5CS1 and P5CS2) and of genes related to priming processes (i.e. MPK3 and MPK6) were also up-regulated. In addition, reactive oxygen species scavenging activities were enhanced in tomatoes treated with EJ01 in stressed conditions. GFP-tagged EJ01 displayed colonization in the rhizosphere and endosphere in the roots of Arabidopsis. In conclusion, the newly isolated Enterobacter sp. EJ01 is a likely PGPR and alleviates salt stress in host plants through multiple mechanisms, including the rapid up-regulation of conserved plant salt stress responsive signaling pathways.

Alleviation of Salt Stress by Enterobacter sp. EJ01 in Tomato and Arabidopsis Is Accompanied by Up-Regulation of Conserved Salinity Responsive Factors in Plants

PubMed Central

Kim, Kangmin; Jang, Ye-Jin; Lee, Sang-Myeong; Oh, Byung-Taek; Chae, Jong-Chan; Lee, Kui-Jae

2014-01-01

Microbiota in the niches of the rhizosphere zones can affect plant growth and responses to environmental stress conditions via mutualistic interactions with host plants. Specifically, some beneficial bacteria, collectively referred to as Plant Growth Promoting Rhizobacteria (PGPRs), increase plant biomass and innate immunity potential. Here, we report that Enterobacter sp. EJ01, a bacterium isolated from sea china pink (Dianthus japonicus thunb) in reclaimed land of Gyehwa-do in Korea, improved the vegetative growth and alleviated salt stress in tomato and Arabidopsis. EJ01 was capable of producing 1-aminocy-clopropane-1-carboxylate (ACC) deaminase and also exhibited indole-3-acetic acid (IAA) production. The isolate EJ01 conferred increases in fresh weight, dry weight, and plant height of tomato and Arabidopsis under both normal and high salinity conditions. At the molecular level, short-term treatment with EJ01 increased the expression of salt stress responsive genes such as DREB2b, RD29A, RD29B, and RAB18 in Arabidopsis. The expression of proline biosynthetic genes (i.e. P5CS1 and P5CS2) and of genes related to priming processes (i.e. MPK3 and MPK6) were also up-regulated. In addition, reactive oxygen species scavenging activities were enhanced in tomatoes treated with EJ01 in stressed conditions. GFP-tagged EJ01 displayed colonization in the rhizosphere and endosphere in the roots of Arabidopsis. In conclusion, the newly isolated Enterobacter sp. EJ01 is a likely PGPR and alleviates salt stress in host plants through multiple mechanisms, including the rapid up-regulation of conserved plant salt stress responsive signaling pathways. PMID:24598995

Reverse transcription loop-mediated isothermal amplification for species-specific detection of tomato chlorotic spot orthotospovirus

USDA-ARS?s Scientific Manuscript database

Tomato chlorotic spot virus (TCSV) is an emerging tospovirus that can cause severe disease on tomato plants. There are at least four tospoviruses infecting tomato, and mixed infection of various viruses in a field crop is quite common. With similarity in the symptomatology and cross serological reac...

Complete genome sequence of a tomato infecting tomato mottle mosaic virus in New York

USDA-ARS?s Scientific Manuscript database

Complete genome sequence of an emerging isolate of tomato mottle mosaic virus (ToMMV) infecting experimental nicotianan benthamiana plants in up-state New York was obtained using small RNA deep sequencing. ToMMV_NY-13 shared 99% sequence identity to ToMMV isolates from Mexico and Florida. Broader d...

Expression of a highly basic peroxidase gene in NaCl-adapted tomato cell suspensions.

PubMed

Medina, M I; Botella, M A; Quesada, M A; Valpuesta, V

1997-05-05

A tomato peroxidase gene, TPX2, that is only weakly expressed in the roots of young tomato seedlings is highly expressed in tomato suspension cells adapted to high external NaCl concentration. The protein encoded by this gene, with an isolectric point value of approximately 9.6, is found in the culture medium of the growing cells. Our data suggest that the expression of TPX2 in the salt-adapted cells is not the result of the elicitation imposed by the in vitro culture or the presence of high NaCl concentration in the medium.

Papaya is not a host for Tomato Yellow Leaf Curl Virus

USDA-ARS?s Scientific Manuscript database

The economic value of tomato production is threatened by tomato yellow leaf-curl virus TYLCV and its vector, the silverleaf whitefly Bemisia tabaci biotype B (Gennadius) (Hemiptera: Aleyrodidae). Use of papaya Carica papaya L. as a banker plant for a whitefly parasitoid shows promise as a whitefly m...

Demonstration tests of infrared peeling system with electrical emitters for tomatoes

USDA-ARS?s Scientific Manuscript database

Infrared (IR) dry-peeling is an emerging technology that could avoid the drawbacks of steam and lye peeling of tomatoes. The objectives of this research was to evaluate the performance of an IR peeling system at two tomato processing plants located in California and to compare product quality, peela...

Plant age, communication, and resistance to herbivores: young sagebrush plants are better emitters and receivers.

PubMed

Shiojiri, Kaori; Karban, Richard

2006-08-01

Plants progress through a series of distinct stages during development, although the role of plant ontogeny in their defenses against herbivores is poorly understood. Recent work indicates that many plants activate systemic induced resistance after herbivore attack, although the relationship between resistance and ontogeny has not been a focus of this work. In addition, for sagebrush and a few other species, individuals near neighbors that experience simulated herbivory become more resistant to subsequent attack. Volatile, airborne cues are required for both systemic induced resistance among branches and for communication among individuals. We conducted experiments in stands of sagebrush of mixed ages to determine effects of plant age on volatile signaling between branches and individuals. Young and old control plants did not differ in levels of chewing damage that they experienced. Systemic induced resistance among branches was only observed for young plants. Young plants showed strong evidence of systemic resistance only if airflow was permitted among branches; plants with only vascular connections showed no systemic resistance. We also found evidence for volatile communication between individuals. For airborne communication, young plants were more effective emitters of cues as well as more responsive receivers of volatile cues.

Establishment of papaya banker plant system for Parasitoid, Encarsia sophia (Hymenoptera: Aphilidae) against Bemisia tabaci (Hemiptera: Aleyrodidae) in greenhouse tomato production

USDA-ARS?s Scientific Manuscript database

The silverleaf whitefly, Bemisia tabaci biotype B (Gennadius) (Hemiptera:Aleyrodidae), is a key pest of tomato (Solanum lycopersicum L.) and other vegetable crops worldwide. To combat this pest, a non-crop banker plant system was evaluated that employs a parasitoid, Encarsia sophia (Girault & Dodd) ...

Expression analysis of human β-secretase in transgenic tomato fruits.

PubMed

Kim, H-S; Youm, J-W; Moon, K-B; Ha, J-H; Kim, Y-H; Joung, H; Jeon, J-H

2012-03-01

An emerging strategy in biomanufacturing involves using transgenic plants to express recombinant pharmaceutical and industrial proteins in large quantities. β-Site APP cleaving enzyme 1 (β-secretase 1, BACE1) is an enzyme involved in the abnormal production of Aβ42, the major component of senile plaques in Alzheimer's disease (AD). Thus, BACE1 represents a key target protein in the development of new potential drugs to treat Alzheimer's disease. We aimed to develop a tomato-derived recombinant BACE1 (rBACE1) protein to serve as a vaccine antigen that would promote an immune response. We utilized a plant expression cassette, pE8BACE, to optimize BACE1 expression in tomato fruits. Polyemerase chain reaction and Southern blot analyses verified integration of the BACE1 gene into the plant genome. Northern and Western blot analyses demonstrated successful mRNA and protein expression of rBACE1, respectively; the Sensizyme assay kit estimated the expression level of rBACE1 protein at 136 ± 7 ng mg⁻¹ total soluble protein. The tomato-derived rBACE1 retains its activity for a long storage period at cool or room temperature, and is highly resistant to degradation in conditions such as low acidity. Tomato-derived rBACE1 was severely degraded by heat or boiling. The proteolytic activity of tomato-derived rBACE1, confirmed by fluorescence resonance transfer assay, was similar to that of a commercial sample of Escherichia coli-derived BACE1. Copyright © 2011 Elsevier Inc. All rights reserved.

Amount of cadmium associated with Cd-binding protein in roots of young plants. [Agrostis gigantea

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rauser, W.E.

1986-04-01

The partitioning of Cd between roots and shoots was determined for young plants exposed to Cd in nutrient solution. The intentionally high concentration of 3 ..mu..m Cd was used to assess the role of root Cd-binding protein (Cd-BP) in Cd detoxification. The roots of tomatoes exposed to Cd retained 60-84% of the plant Cd from day 2 through day 9 without toxicity symptoms evident. Cd-BP did not contribute to Cd retention over the initial 4 days, only 1-4% of the root Cd was in this protein fraction. Maize roots retained 59-66% of the plant Cd from day 1 through daymore » 7. The Cd-BP fraction bound 8-19% of the root Cd on day 1 and 31-55% by day 7. Cd toxicity symptoms occurred in leaves by 4 days. In the grass Agrostis gigantea the roots retained 73-85% of the seedling Cd after 1 day and for another 6 days. A high proportion of the root Cd(34-68%) was in the Cd-BP fraction after one day and continued to be so to day 7 (46-64%). No Cd toxicity symptoms were evident. Only the specific pattern of rapid, early and sustained production of Cd-BP observed in Agrostis was consistent with the putative detoxification role for Cd-BP.« less

AM symbiosis alters phenolic acid content in tomato roots

PubMed Central

Flors, Victor; García, Juan M; Pozo, Maria J

2010-01-01

Arbuscular mycorrhizal (AM) fungi colonize the roots of most plants to establish a mutualistic symbiosis leading to important benefits for plant health. We have recently shown that AM symbiosis alters both transcriptional and hormonal profiles in tomato roots, many of these changes related to plant defense. Here, we analytically demonstrate that the levels of other important defense-related compounds as phenolic acids are also altered in the symbiosis. Both caffeic and chlorogenic acid levels significantly decreased in tomato roots upon mycorrhization, while ferulic acid increased. Moreover, in the case of caffeic acid a differential reduction was observed depending on the colonizing AM fungus. The results confirm that AM associations imply the regulation of plant defense responses, and that the host changes may vary depending on the AM fungus involved. The potential implications of altered phenolic acid levels on plant control over mycorrhizal colonization and in the plant resistance to pathogens is discussed. PMID:21490421

Phenotypic Characterization of a Diversity Panel of Tomato

USDA-ARS?s Scientific Manuscript database

At the USDA, ARS Plant Genetic Resources Unit (PGRU) we have phenotypically characterized more than 2,000 accessions of tomato (Solanum lycopersicum L.) for which data are publically available on the National Plant Germplasm System (NPGS) Germplasm Resources Information Network (GRIN) (http://www.ar...

Rapid identification of causal mutations in tomato EMS populations via mapping-by-sequencing.

PubMed

Garcia, Virginie; Bres, Cécile; Just, Daniel; Fernandez, Lucie; Tai, Fabienne Wong Jun; Mauxion, Jean-Philippe; Le Paslier, Marie-Christine; Bérard, Aurélie; Brunel, Dominique; Aoki, Koh; Alseekh, Saleh; Fernie, Alisdair R; Fraser, Paul D; Rothan, Christophe

2016-12-01

The tomato is the model species of choice for fleshy fruit development and for the Solanaceae family. Ethyl methanesulfonate (EMS) mutants of tomato have already proven their utility for analysis of gene function in plants, leading to improved breeding stocks and superior tomato varieties. However, until recently, the identification of causal mutations that underlie particular phenotypes has been a very lengthy task that many laboratories could not afford because of spatial and technical limitations. Here, we describe a simple protocol for identifying causal mutations in tomato using a mapping-by-sequencing strategy. Plants displaying phenotypes of interest are first isolated by screening an EMS mutant collection generated in the miniature cultivar Micro-Tom. A recombinant F 2 population is then produced by crossing the mutant with a wild-type (WT; non-mutagenized) genotype, and F 2 segregants displaying the same phenotype are subsequently pooled. Finally, whole-genome sequencing and analysis of allele distributions in the pools allow for the identification of the causal mutation. The whole process, from the isolation of the tomato mutant to the identification of the causal mutation, takes 6-12 months. This strategy overcomes many previous limitations, is simple to use and can be applied in most laboratories with limited facilities for plant culture and genotyping.

A role for APETALA1/fruitfull transcription factors in tomato leaf development.

PubMed

Burko, Yogev; Shleizer-Burko, Sharona; Yanai, Osnat; Shwartz, Ido; Zelnik, Iris Daphne; Jacob-Hirsch, Jasmine; Kela, Itai; Eshed-Williams, Leor; Ori, Naomi

2013-06-01

Flexible maturation rates underlie part of the diversity of leaf shape, and tomato (Solanum lycopersicum) leaves are compound due to prolonged organogenic activity of the leaf margin. The CINCINNATA-teosinte branched1, cycloidea, PCF (CIN-TCP) transcription factor lanceolate (LA) restricts this organogenic activity and promotes maturation. Here, we show that tomato APETALA1/fruitfull (AP1/FUL) MADS box genes are involved in tomato leaf development and are repressed by LA. AP1/FUL expression is correlated negatively with LA activity and positively with the organogenic activity of the leaf margin. LA binds to the promoters of the AP1/FUL genes MBP20 and TM4. Overexpression of MBP20 suppressed the simple-leaf phenotype resulting from upregulation of LA activity or from downregulation of class I knotted like homeobox (KNOXI) activity. Overexpression of a dominant-negative form of MBP20 led to leaf simplification and partly suppressed the increased leaf complexity of plants with reduced LA activity or increased KNOXI activity. Tomato plants overexpressing miR319, a negative regulator of several CIN-TCP genes including LA, flower with fewer leaves via an SFT-dependent pathway, suggesting that miR319-sensitive CIN-TCPs delay flowering in tomato. These results identify a role for AP1/FUL genes in vegetative development and show that leaf and plant maturation are regulated via partially independent mechanisms.

Anti-phytopathogen potential of endophytic actinobacteria isolated from tomato plants (Lycopersicon esculentum) in southern Brazil, and characterization of Streptomyces sp. R18(6), a potential biocontrol agent.

PubMed

de Oliveira, Margaroni Fialho; da Silva, Mariana Germano; Van Der Sand, Sueli T

2010-09-01

Tomato plants (Lycopersicon esculentum) are highly susceptible to phytopathogen attack. The resulting intensive application of pesticides on tomato crops can affect the environment and health of humans and animals. The objective of this study was to select potential biocontrol agents among actinobacteria from tomato plants, in a search for alternative phytopathogen control. We evaluated 70 endophytic actinobacteria isolated from tomato plants in southern Brazil, testing their antimicrobial activity, siderophore production, indoleacetic acid production, and phosphate solubility. The actinomycete isolate with the highest antimicrobial potential was selected using the agar-well diffusion method, in order to optimize conditions for the production of compounds with antimicrobial activity. For this study, six growth media (starch casein-SC, ISP2, Bennett's, Sahin, Czapek-Dox, and TSB), three temperatures (25 degrees C, 30 degrees C, and 35 degrees C) and different pH were tested. Of the actinobacteria tested, 88.6% showed antimicrobial activity against at least one phytopathogen, 72.1% showed a positive reaction for indoleacetic acid production, 86.8% produced siderophores and 16.2% showed a positive reaction for phosphate solubility. Isolate R18(6) was selected due to its antagonistic activity against all phytopathogenic microorganisms tested in this study. The best conditions for production were observed in the SC medium, at 30 degrees C and pH 7.0. The isolate R18(6) showed close biochemical and genetic similarity to Streptomyces pluricolorescens. Copyright 2010 Elsevier Masson SAS. All rights reserved.

The roles of call wall invertase inhibitor in regulating chilling tolerance in tomato.

PubMed

Xu, Xiao-Xia; Hu, Qin; Yang, Wan-Nian; Jin, Ye

2017-11-09

Hexoses are important metabolic signals that respond to abiotic and biotic stresses. Cold stress adversely affects plant growth and development, limiting productivity. The mechanism by which sugars regulate plant cold tolerance remains elusive. We examined the function of INVINH1, a cell wall invertase inhibitor, in tomato chilling tolerance. Cold stress suppressed the transcription of INVINH1 and increased that of cell wall invertase genes, Lin6 and Lin8 in tomato seedlings. Silencing INVINH1 expression in tomato increased cell wall invertase activity and enhanced chilling tolerance. Conversely, transgenic tomatoes over-expressing INVINH1 showed reduced cell wall invertase activity and were more sensitive to cold stress. Chilling stress increased glucose and fructose levels, and the hexoses content increased or decreased by silencing or overexpression INVINH1. Glucose applied in vitro masked the differences in chilling tolerance of tomato caused by the different expressions of INVINH1. The repression of INVINH1 or glucose applied in vitro regulated the expression of C-repeat binding factors (CBFs) genes. Transcript levels of NCED1, which encodes 9-cisepoxycarotenoid dioxygenase (NCED), a key enzyme in the biosynthesis of abscisic acid, were suppressed by INVINH1 after exposure to chilling stress. Meanwhile, application of ABA protected plant from chilling damage caused by the different expression of INVINH1. In tomato, INVINH1 plays an important role in chilling tolerance by adjusting the content of glucose and expression of CBFs.

Preparation of Graphene Oxide and Its Mechanism in Promoting Tomato Roots Growth.

PubMed

Jiao, Jingzhi; Cheng, Fan; Zhang, Xuekun; Xie, Lingli; Li, Zhiyang; Yuan, Chengfei; Xu, Benbo; Zhang, Liming

2016-04-01

Graphene oxide is a new kind of nanomaterial. The graphene oxide was prepared and its quality detected by atomic force microscopy (AFM) and transmission electron microscopy (TEM), for better understanding of effects of the nanomaterial on plants. Wild type. (WT) tomato (Solanum lycopersicum) germplasm 'New Yorker' and corresponding transgenic plants (Prd29A::LeNCED1) were treated with prepared graphene oxide. 9-cis-epoxycarotenoid dioxygenase (NCED) is a key gene for ABA biosynthesis and overexpression of the NCED resulted in ABA accumulation and higher drought tolerance. Seminal root length in the WT tomato was longer than that in the control samples when the seedlings were treated with 20 mg/L graphene oxide for 15 days. In contrast, the same treatment resulted in shorter seminal root length in the transgenic plants compared with control samples. The graphene oxide treatments led to lower Superoxide Dismutase (SOD), Peroxidase (POD), Catalase (CAT) activity and Malondialdehyde (MDA) content in the WT and transgenic plants. 20 mg/L graphene oxide treatment also affected the transcript levels of IAA7, IAA4 and IAA10 but the effect on the wild type and corresponding transgenic plants was different. IAA4 transcription level decreased both in the WT and Prd29A::LeNCED1 transgenic plants while the IAA7 transcription level decreased in the transgenic plants and increased in the WT tomato. The IAA10 transcription level decreased in the WT tomato and increased in the Prd29A::LeNCED1 transgenic plants. Graphene oxide treatments resulted in higher transcription level of ABCG25 and ABCG40 in the WT plants but had no significant effect on transgenic plants. The transcription level of NCED in the WT and Prd29A::LeNCED1 transgenic plants treated with graphene oxide increased significantly, however, it was higher in the transgenic plants than in the WT tomato after 15 d treatment, indicating that the graphene oxide activated the rd29A promoter as does drought and salt. The HD

Crinivirus and begomovirus detection in tomato plantlets and weeds associated to nurseries in Cartago province

USDA-ARS?s Scientific Manuscript database

The aim of this work was to detect plant infections caused by Tomato chlorosis virus (ToCV) and begomoviruses in tomato plantlets, as well as in weeds growing around nursery greenhouses. During one year, starting in April 2008, 168 leaf tissue samples were collected, 90 tomato plantlets and 78 weed...

Genome-wide transcriptomic analysis of BR-deficient Micro-Tom reveals correlations between drought stress tolerance and brassinosteroid signaling in tomato.

PubMed

Lee, Jinsu; Shim, Donghwan; Moon, Suyun; Kim, Hyemin; Bae, Wonsil; Kim, Kyunghwan; Kim, Yang-Hoon; Rhee, Sung-Keun; Hong, Chang Pyo; Hong, Suk-Young; Lee, Ye-Jin; Sung, Jwakyung; Ryu, Hojin

2018-06-01

Brassinosteroids (BRs) are plant steroid hormones that play crucial roles in a range of growth and developmental processes. Although BR signal transduction and biosynthetic pathways have been well characterized in model plants, their biological roles in an important crop, tomato (Solanum lycopersicum), remain unknown. Here, cultivated tomato (WT) and a BR synthesis mutant, Micro-Tom (MT), were compared using physiological and transcriptomic approaches. The cultivated tomato showed higher tolerance to drought and osmotic stresses than the MT tomato. However, BR-defective phenotypes of MT, including plant growth and stomatal closure defects, were completely recovered by application of exogenous BR or complementation with a SlDWARF gene. Using genome-wide transcriptome analysis, 619 significantly differentially expressed genes (DEGs) were identified between WT and MT plants. Several DEGs were linked to known signaling networks, including those related to biotic/abiotic stress responses, lignification, cell wall development, and hormone responses. Consistent with the higher susceptibility of MT to drought stress, several gene sets involved in responses to drought and osmotic stress were differentially regulated between the WT and MT tomato plants. Our data suggest that BR signaling pathways are involved in mediating the response to abiotic stress via fine-tuning of abiotic stress-related gene networks in tomato plants. Copyright © 2018. Published by Elsevier Masson SAS.

Unraveling the Protein Network of Tomato Fruit in Response to Necrotrophic Phytopathogenic Rhizopus nigricans

PubMed Central

Pan, Xiaoqi; Zhu, Benzhong; Luo, Yunbo; Fu, Daqi

2013-01-01

Plants are endowed with a sophisticated defense mechanism that gives signals to plant cells about the immediate danger from surroundings and protects them from pathogen invasion. In the search for the particular proteins involved in fruit defense responses, we report here a comparative analysis of tomato fruit (Solanum lycopersicum cv. Ailsa Craig) infected by Rhizopus nigricans Ehrenb, which is a significant contributor to postharvest rot disease in fresh tomato fruits. In total, four hundred forty-five tomato proteins were detected in common between the non-infected group and infected tomato fruit of mature green. Forty-nine differentially expressed spots in 2-D gels were identified, and were sorted into fifteen functional groups. Most of these proteins participate directly in the stress response process, while others were found to be involved in several equally important biological processes: protein metabolic process, carbohydrate metabolic process, ethylene biosynthesis, and cell death and so on. These responses occur in different cellular components, both intra- and extracellular spaces. The differentially expressed proteins were integrated into several pathways to show the regulation style existing in tomato fruit host. The composition of the collected proteins populations and the putative functions of the identified proteins argue for their roles in pathogen-plant interactions. Collectively results provide evidence that several regulatory pathways contribute to the resistance of tomato fruit to pathogen. PMID:24023804

Biological control strategies for the South American tomato moth (Lepidoptera: Gelechiidae) in greenhouse tomatoes.

PubMed

Cabello, Tomas; Gallego, Juan R; Fernandez, Francisco J; Gamez, Manuel; Vila, Enric; Del Pino, Modesto; Hernandez-Suarez, Estrella

2012-12-01

The South American tomato pinworm, Tuta absoluta (Meyrick) has been introduced into new geographic areas, including the Mediterranean region, where it has become a serious threat to tomato production. Three greenhouse trials conducted in tomato crops during 2009 and 2010 explored control strategies using the egg-parasitoid Trichogramma achaeae Nagaraja and Nagarkatti compared with chemical control. The effectiveness of the predator Nesidiocoris tenuis (Reuter) was also tested. In greenhouses with early pest infestations (discrete generations), periodic inundative releases (eight releases at a rate of 50 adults/m2, twice a week) were necessary to achieve an adequate parasitism level (85.63 +/- 5.70%) early in the growing season. However, only one inoculative release (100 adults/m2) was sufficient to achieve a comparatively high parasitism level (91.03 +/- 12.58%) under conditions of high pest incidence and overlapping generations. Some intraguild competition was observed between T. achaeae and the predator, N. tenuis. This mirid species is commonly used in Mediterranean greenhouse tomato crops for the control of the sweetpotato whitefly, Bemisia tabaci (Gennadius). Tomato cultivars were also observed to influence the activity of natural enemies, mainly N. tenuis (whose average numbers ranged between 0.17 +/- 0.03 and 0.41 +/- 0.05 nymphs per leaf depending on the cultivar). This may be because of differences in plant nutrients in different cultivars, which may affect the feeding of omnivorous insects. In contrast, cultivar effects on T. achaeae were less apparent or possibly nonexistent. Nevertheless, there was an indirect effect in as much as T. achaeae was favored in cultivars not liked by N. tenuis.

Metabolomics by Proton High-Resolution Magic-Angle-Spinning Nuclear Magnetic Resonance of Tomato Plants Treated with Two Secondary Metabolites Isolated from Trichoderma.

PubMed

Mazzei, Pierluigi; Vinale, Francesco; Woo, Sheridan Lois; Pascale, Alberto; Lorito, Matteo; Piccolo, Alessandro

2016-05-11

Trichoderma fungi release 6-pentyl-2H-pyran-2-one (1) and harzianic acid (2) secondary metabolites to improve plant growth and health protection. We isolated metabolites 1 and 2 from Trichoderma strains, whose different concentrations were used to treat seeds of Solanum lycopersicum. The metabolic profile in the resulting 15 day old tomato leaves was studied by high-resolution magic-angle-spinning nuclear magnetic resonance (HRMAS NMR) spectroscopy directly on the whole samples without any preliminary extraction. Principal component analysis (PCA) of HRMAS NMR showed significantly enhanced acetylcholine and γ-aminobutyric acid (GABA) content accompanied by variable amount of amino acids in samples treated with both Trichoderma secondary metabolites. Seed germination rates, seedling fresh weight, and the metabolome of tomato leaves were also dependent upon doses of metabolites 1 and 2 treatments. HRMAS NMR spectroscopy was proven to represent a rapid and reliable technique for evaluating specific changes in the metabolome of plant leaves and calibrating the best concentration of bioactive compounds required to stimulate plant growth.

Complete Genome Sequence of Tomato Mosaic Virus Isolated from Jasmine in the United States

PubMed Central

Fillmer, Kornelia; Adkins, Scott; Pongam, Patchara

2015-01-01

Tomato mosaic virus was reported from jasmine in Florida. We present the first complete genome sequence of a tomato mosaic virus isolate from this woody perennial plant in the United States. PMID:26159525

Tomato yellow leaf curl virus infection of a resistant tomato line with a silenced sucrose transporter gene LeHT1 results in inhibition of growth, enhanced virus spread, and necrosis.

PubMed

Eybishtz, Assaf; Peretz, Yuval; Sade, Dagan; Gorovits, Rena; Czosnek, Henryk

2010-02-01

To identify genes involved in resistance of tomato to Tomato yellow leaf curl virus (TYLCV), cDNA libraries from lines resistant (R) and susceptible (S) to the virus were compared. The hexose transporter LeHT1 was found to be expressed preferentially in R tomato plants. The role of LeHT1 in the establishment of TYLCV resistance was studied in R plants where LeHT1 has been silenced using Tobacco rattle virus-induced gene silencing (TRV VIGS). Following TYLCV inoculation, LeHT1-silenced R plants showed inhibition of growth and enhanced virus accumulation and spread. In addition, a necrotic response was observed along the stem and petioles of infected LeHT1-silenced R plants, but not on infected not-silenced R plants. This response was specific of R plants since it was absent in infected LeHT1-silenced S plants. Necrosis had several characteristics of programmed cell death (PCD): DNA from necrotic tissues presented a PCD-characteristic ladder pattern, the amount of a JNK analogue increased, and production of reactive oxygen was identified by DAB staining. A similar necrotic reaction along stem and petioles was observed in LeHT1-silenced R plants infected with the DNA virus Bean dwarf mosaic virus and the RNA viruses Cucumber mosaic virus and Tobacco mosaic virus. These results constitute the first evidence for a necrotic response backing natural resistance to TYLCV in tomato, confirming that plant defense is organized in multiple layers. They demonstrate that the hexose transporter LeHT1 is essential for the expression of natural resistance against TYLCV and its expression correlates with inhibition of virus replication and movement.

Identification of nutrient deficiency in maize and tomato plants by in vivo chlorophyll a fluorescence measurements.

PubMed

Kalaji, Hazem M; Oukarroum, Abdallah; Alexandrov, Vladimir; Kouzmanova, Margarita; Brestic, Marian; Zivcak, Marek; Samborska, Izabela A; Cetner, Magdalena D; Allakhverdiev, Suleyman I; Goltsev, Vasilij

2014-08-01

The impact of some macro (Ca, S, Mg, K, N, P) and micro (Fe) nutrients deficiency on the functioning of the photosynthetic machinery in tomato (Solanum lycopersicum L.) and maize (Zea mays L.) plants grown in hydroponic cultures were investigated. Plants grown on a complete nutrient solution (control) were compared with those grown in a medium, which lacked one of macro- or microelements. The physiological state of the photosynthetic machinery in vivo was analysed after 14-days of deficient condition by the parameters of JIP-test based on fast chlorophyll a fluorescence records. In most of the nutrient-deficient samples, the decrease of photochemical efficiency, increase in non-photochemical dissipation and decrease of the number of active photosystem II (PSII) reaction centres were observed. However, lack of individual nutrients also had nutrient-specific effects on the photochemical processes. In Mg and Ca-deficient plants, the most severe decrease in electron donation by oxygen evolving complex (OEC) was indicated. Sulphur deficiency caused limitation of electron transport beyond PSI, probably due to decrease in the PSI content or activity of PSI electron acceptors; in contrary, Ca deficiency had an opposite effect, where the PSII activity was affected much more than PSI. Despite the fact that clear differences in nutrient deficiency responses between tomato and maize plants were observed, our results indicate that some of presented fluorescence parameters could be used as fluorescence phenotype markers. The principal component analysis of selected JIP-test parameters was presented as a possible species-specific approach to identify/predict the nutrient deficiency using the fast chlorophyll fluorescence records. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Tomato is a highly effective vehicle for expression and oral immunization with Norwalk virus capsid protein.

PubMed

Zhang, Xiuren; Buehner, Norene A; Hutson, Anne M; Estes, Mary K; Mason, Hugh S

2006-07-01

Norwalk virus (NV) is an important agent of epidemic gastroenteritis, and an oral subunit vaccine shows potential for protection. Recombinant Norwalk virus (rNV) capsid protein expressed in plants assembles virus-like particles (VLPs) that are orally immunogenic in mice and humans. In this article we examine rNV expression in tomato and potato using a plant-optimized gene, and test the immunogenicity of dried tomato fruit and potato tuber fed to mice. The synthetic gene increased rNV expression fourfold in tomato and potato plants, which assembled VLP. Four doses of 0.4 g freeze-dried tomato fruit containing 64 microg rNV (40 microg VLPs) induced NV-specific serum IgG and mucosal IgA in > or = 80% of mice, while doses of 0.8 g elicited systemic and mucosal antibody responses in all mice. Feedings of 1 g freeze-dried potato tuber containing 120 microg rNV (90 microg VLPs) were required to produce 100% responsiveness. Oxidation of phenolic compounds upon rehydration of dried tuber caused significant VLP instability, thus decreasing immunogenicity. Air-dried tomato fruit stimulated stronger immune responses than freeze-dried fruit of the same mass, perhaps by limiting the destruction of plant cell matrix and membrane systems that occurs with freeze-drying. Thus, rNV in dried transgenic tomato fruit was a more potent immunogen than that in dried potato tubers, based on the total VLPs ingested. These findings support the use of stabilized, dried tomato fruit for oral delivery of subunit vaccines.

77 FR 3433 - Notice of Request for Extension of Approval of an Information Collection; Importation of Tomatoes...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-01-24

... Collection; Importation of Tomatoes From Certain Central American Countries AGENCY: Animal and Plant Health... collection associated with regulations for the importation of tomatoes from certain Central American... INFORMATION CONTACT: For information on regulations for the importation of tomatoes from certain Central...

Biological control of corky root in tomato.

PubMed

Fiume, G; Fiume, F

2008-01-01

Corky root caused by Pyrenochaeta lycopersici (Schneider et Gerlach) is one of the most important soil borne fungal pathogens which develops in the soils, causing diseases in different crops. The research was carried out to evaluate the effectiveness of the biological control of corky root on tomato. Biological control was performed by using Trichoderma viride Pers. 18/17 SS, Streptomyces spp. AtB42 and Bacillus subtilis M51 PI. According to present and future regulations on the use of chemical fungicides and considering that treatments must avoids environmental pollution, the main object of this research was to find alternative strategies by using biocontrol agents against P. lycopersici that affect tomato plants. In laboratory, the effectiveness of T. viride 18/17 SS, Streptomyces spp. AtB42 and B. subtilis M51 PI to control P. lycopersici were studied. In greenhouse, the research was carried out comparing the following treatments: 1) untreated control; 2) T. viride 18/17 SS; 3) Streptomyces spp. AtB42; 4) B. subtilis M51 PI. Roots of plants of tomato H3028 Hazera were treated with the antagonist suspensions just prior of transplant. Treatments were repeated about 2 months after, with the same suspensions sprayed on the soil to the plant collar. In dual culture, the inhibition of P. lycopersici ranged up to 81.2% (caused from T. viride 18/17 SS), 75.6% (from Streptomyces spp. AtB42) and 66.8% (from B. subtilis M51 PI). In greenhouse trials, with regard to corky root symptoms, all treated plots showed signifycative differences compared to untreated. T. viride gave the better results followed by Streptomyces spp. and then by B. subtilis. The fungus antagonist showed good root surface competence such as demonstrated its persistence on the roots surface of the tomato plants whose roots were treated with T. viride 18/17 SS up to 2 months before.

Specific Responses of Salmonella enterica to Tomato Varieties and Fruit Ripeness Identified by In Vivo Expression Technology

PubMed Central

Noel, Jason T.; Arrach, Nabil; Alagely, Ali; McClelland, Michael; Teplitski, Max

2010-01-01

Background Recent outbreaks of vegetable-associated gastroenteritis suggest that enteric pathogens colonize, multiply and persist in plants for extended periods of time, eventually infecting people. Genetic and physiological pathways, by which enterics colonize plants, are still poorly understood. Methodology/Principal Findings To better understand interactions between Salmonella enterica sv. Typhimurium and tomatoes, a gfp-tagged Salmonella promoter library was screened inside red ripe fruits. Fifty-one unique constructs that were potentially differentially regulated in tomato relative to in vitro growth were identified. The expression of a subset of these promoters was tested in planta using recombinase-based in vivo expression technology (RIVET) and fitness of the corresponding mutants was tested. Gene expression in Salmonella was affected by fruit maturity and tomato cultivar. A putative fadH promoter was upregulated most strongly in immature tomatoes. Expression of the fadH construct depended on the presence of linoleic acid, which is consistent with the reduced accumulation of this compound in mature tomato fruits. The cysB construct was activated in the fruit of cv. Hawaii 7997 (resistant to a race of Ralstonia solanacearum) more strongly than in the universally susceptible tomato cv. Bonny Best. Known Salmonella motility and animal virulence genes (hilA, flhDC, fliF and those encoded on the pSLT virulence plasmid) did not contribute significantly to fitness of the bacteria inside tomatoes, even though deletions of sirA and motA modestly increased fitness of Salmonella inside tomatoes. Conclusions/Significance This study reveals the genetic basis of the interactions of Salmonella with plant hosts. Salmonella relies on a distinct set of metabolic and regulatory genes, which are differentially regulated in planta in response to host genotype and fruit maturity. This enteric pathogen colonizes tissues of tomatoes differently than plant pathogens, and relies

Control of the Tomato Leafminer, Tuta absoluta (Lepidoptera: Gelechiidae), in Open-Field Tomatoes by Indigenous Natural Enemies Occurring in Israel.

PubMed

Shaltiel-Harpaz, Liora; Gerling, Dan; Graph, Shaul; Kedoshim, Hendrika; Azolay, Lotem; Rozenberg, Tamir; Nachache, Yaakov; Steinberg, Shimon; Allouche, Arnon; Alon, Tamar

2016-02-01

The tomato leafminer, Tuta absoluta (Meyrick), had established in Israel by 2010, attacking both open-field tomatoes and greenhouse crops.We searched for its natural enemies in open-field tomatoes, and tried to determine their potential for controlling this pest. We surveyed the local natural enemies in open tomato fields and measured their impact on pest populations in an unsprayed field. We assessed the suppressive ability of the dominant hemipteran predator, Nesidiocoris tenuis Reuter, against T. absoluta under controlled laboratory conditions and evaluated the impact of its augmentation on T. absoluta control in open-field tomatoes. We found five natural enemy species:the predator, N. tenuis, two braconids, and two eulophids. Predation accounted for 64.5±9.2% (mean ± SE) of T. absoluta larval mortality, whereas parasitism accounted for 20.96±7.5%. Together, they eliminated the pest population at tomato harvest time. Under controlled conditions, predation by N. tenuis rose from 58 to 72% with increased density of T. absoluta, suggesting positive density dependence. The reduction of T. absoluta (83%) by N. tenuis was higher than that of Bemisia tabaci (32%), suggesting a preference of N. tenuis for T. absoluta. Augmentation of N.tenuis was as effective as conventional treatment insecticide treatment, and plant damage was low and did not seem to affect yield. Results indicate that reduced pesticide use enables indigenous natural enemies, particularly N.tenuis, to successfully control T. absoluta and prevent crop damage in open-field tomatoes.

In vitro food production for isolated closed environments: formation of ripe tomato fruits from excised flower buds.

PubMed

Applewhite, P B; K-Sawhney, R; Galston, A W

1997-01-01

Excised preanthesis flower buds of young Pixie Hybrid tomato plants develop into red ripe fruits in aseptic culture on a modified Murashige-Skoog medium with 3% sucrose at pH 5.8. The addition of certain synthetic auxins (IAA, NAA, IBA), auxin precursors (ISA), or cytokinins (KIN, IPA, ZEA, BAP) to the medium improved the percentage of buds developing into fruits, the weight of the ripe fruits, or both. The best results were obtained by an auxin-cytokinin combination of 10 microM IBA with 1 microM BAP. Storage of the excised buds at low temperature (6 degrees C) for up to 4 weeks before transfer to 27 degrees C caused only minimal deterioration in size and number of the fruit crop. Extension of low-temperature storage to 8 weeks produced smaller fruits that took longer to develop. This system could produce fresh, ripe small tomatoes on a sustained basis for up to 2 months for an isolated environment such as a space vehicle or submarine.

Endogenous Abscisic Acid Promotes Hypocotyl Growth and Affects Endoreduplication during Dark-Induced Growth in Tomato (Solanum lycopersicum L.)

PubMed Central

Humplík, Jan F.; Bergougnoux, Véronique; Jandová, Michaela; Šimura, Jan; Pěnčík, Aleš; Tomanec, Ondřej; Rolčík, Jakub; Novák, Ondřej; Fellner, Martin

2015-01-01

Dark-induced growth (skotomorphogenesis) is primarily characterized by rapid elongation of the hypocotyl. We have studied the role of abscisic acid (ABA) during the development of young tomato (Solanum lycopersicum L.) seedlings. We observed that ABA deficiency caused a reduction in hypocotyl growth at the level of cell elongation and that the growth in ABA-deficient plants could be improved by treatment with exogenous ABA, through which the plants show a concentration dependent response. In addition, ABA accumulated in dark-grown tomato seedlings that grew rapidly, whereas seedlings grown under blue light exhibited low growth rates and accumulated less ABA. We demonstrated that ABA promotes DNA endoreduplication by enhancing the expression of the genes encoding inhibitors of cyclin-dependent kinases SlKRP1 and SlKRP3 and by reducing cytokinin levels. These data were supported by the expression analysis of the genes which encode enzymes involved in ABA and CK metabolism. Our results show that ABA is essential for the process of hypocotyl elongation and that appropriate control of the endogenous level of ABA is required in order to drive the growth of etiolated seedlings. PMID:25695830

Temperature field for radiative tomato peeling

NASA Astrophysics Data System (ADS)

Cuccurullo, G.; Giordano, L.

2017-01-01

Nowadays peeling of tomatoes is performed by using steam or lye, which are expensive and polluting techniques, thus sustainable alternatives are searched for dry peeling and, among that, radiative heating seems to be a fairly promising method. This paper aims to speed up the prediction of surface temperatures useful for realizing dry-peeling, thus a 1D-analytical model for the unsteady temperature field in a rotating tomato exposed to a radiative heating source is presented. Since only short times are of interest for the problem at hand, the model involves a semi-infinite slab cooled by convective heat transfer while heated by a pulsating heat source. The model being linear, the solution is derived following the Laplace Transform method. A 3D finite element model of the rotating tomato is introduced as well in order to validate the analytical solution. A satisfactory agreement is attained. Therefore, two different ways to predict the onset of the peeling conditions are available which can be of help for proper design of peeling plants. Particular attention is paid to study surface temperature uniformity, that being a critical parameter for realizing an easy tomato peeling.

Ethylene sensitivity and relative air humidity regulate root hydraulic properties in tomato plants.

PubMed

Calvo-Polanco, Monica; Ibort, Pablo; Molina, Sonia; Ruiz-Lozano, Juan Manuel; Zamarreño, Angel María; García-Mina, Jose María; Aroca, Ricardo

2017-11-01

The effect of ethylene and its precursor ACC on root hydraulic properties, including aquaporin expression and abundance, is modulated by relative air humidity and plant sensitivity to ethylene. Relative air humidity (RH) is a main factor contributing to water balance in plants. Ethylene (ET) is known to be involved in the regulation of root water uptake and stomatal opening although its role on plant water balance under different RH is not very well understood. We studied, at the physiological, hormonal and molecular levels (aquaporins expression, abundance and phosphorylation state), the plant responses to exogenous 1-aminocyclopropane-1-carboxylic acid (ACC; precursor of ET) and 2-aminoisobutyric acid (AIB; inhibitor of ET biosynthesis), after 24 h of application to the roots of tomato wild type (WT) plants and its ET-insensitive never ripe (nr) mutant, at two RH levels: regular (50%) and close to saturation RH. Highest RH induced an increase of root hydraulic conductivity (Lp o ) of non-treated WT plants, and the opposite effect in nr mutants. The treatment with ACC reduced Lp o in WT plants at low RH and in nr plants at high RH. The application of AIB increased Lp o only in nr plants at high RH. In untreated plants, the RH treatment changed the abundance and phosphorylation of aquaporins that affected differently both genotypes according to their ET sensitivity. We show that RH is critical in regulating root hydraulic properties, and that Lp o is affected by the plant sensitivity to ET, and possibly to ACC, by regulating aquaporins expression and their phosphorylation status. These results incorporate the relationship between RH and ET in the response of Lp o to environmental changes.

A spectroscopy-based detector to monitor tomato growth condition in greenhouse

NASA Astrophysics Data System (ADS)

Yang, Ce; Li, Minzan; Cui, Di

2008-12-01

A spectroscopy-based detector is developed to measure the nitrogen and chlorophyll content of tomato leaves and then to predict the growth condition of tomato plants in greenhouse. The detector uses two wavebands, 527 nm and 762 nm, since it is proved that these wavebands are sensitive to nitrogen and chlorophyll content in plant leaves by previous field test. The detector contains: A Y-type optic fiber, two silicon photocells, a signal processing unit, and a MCU. Light reflection from tomato leaves is transmitted by the Y-type optic fiber to the surface of the silicon photo cells, which transfer optical signal into electrical signal. Then the analog signal is amplified to conform to the TTL level signal standard and finally converted to digital signal by MAX186. After that, the MCU carries on a series of actions, including data calculating, displaying and storage. Using the measured data, the Normalized Difference Vegetation Index (NDVI) is calculated to estimate the nitrogen and chlorophyll content in plant leaves. The result is directly displayed on an LCD screen. Users have an option in saving data, either into a USB-memory stick or into a database over the PC serial port. The detector is portable, inexpensive, and convenient, which make it meet farmers' need in China. The performance test shows that the growth model works very well, and the device has high accuracy in predicting the growth condition of tomato plants in greenhouse.

Imaging O2 changes induced in tomato roots by fungal pathogen

NASA Astrophysics Data System (ADS)

Rubol, S.; Turco, E.; Rodeghiero, M.; Bellin, A.

2014-12-01

In the last decade, planar optodes have demonstrated to be a useful non-invasive tool to monitor real time oxygen concentrations in a wide range of applications. However, only limited investigations have been carried out to explore the use of optodes in plant respiration studies. In particular, their use to study plant-pathogen interactions has been not deeply investigated. Here, we present for the first time an in vitro experimental setup capable to depict the dynamical effects of the fungal pathogen Fusarium oxysporum f.sp. lycopersici (Fol) on tomato roots by the use of a recently developed optical non-invasive optode oxygen sensor (Visisens, Presens, Germany). Fol is a soil-borne pathogen and the causal agent of wilt in tomato plants, a destructive worldwide disease. The interaction Fol-tomato is widely accepted as a model system in plant pathology. In this work, oxygen concentrations are monitored continuously in time and considered a proxy for root respiration and metabolic activity. The experimental procedure reveals three different dynamic stages: 1) a uniform oxygen consumption in tomato roots earlier before pathogen colonization, 2) a progressive decrease in the oxygen concentration indicating a high metabolic activity as soon as the roots were surrounded and colonized by the fungal mycelium, and 3) absence of root respiration, as a consequence of root death. Our results suggest the ability of the fungal mycelium to move preferentially towards and along the root as a consequence of the recognition event.

A DEMETER-like DNA demethylase governs tomato fruit ripening.

PubMed

Liu, Ruie; How-Kit, Alexandre; Stammitti, Linda; Teyssier, Emeline; Rolin, Dominique; Mortain-Bertrand, Anne; Halle, Stefanie; Liu, Mingchun; Kong, Junhua; Wu, Chaoqun; Degraeve-Guibault, Charlotte; Chapman, Natalie H; Maucourt, Mickael; Hodgman, T Charlie; Tost, Jörg; Bouzayen, Mondher; Hong, Yiguo; Seymour, Graham B; Giovannoni, James J; Gallusci, Philippe

2015-08-25

In plants, genomic DNA methylation which contributes to development and stress responses can be actively removed by DEMETER-like DNA demethylases (DMLs). Indeed, in Arabidopsis DMLs are important for maternal imprinting and endosperm demethylation, but only a few studies demonstrate the developmental roles of active DNA demethylation conclusively in this plant. Here, we show a direct cause and effect relationship between active DNA demethylation mainly mediated by the tomato DML, SlDML2, and fruit ripening- an important developmental process unique to plants. RNAi SlDML2 knockdown results in ripening inhibition via hypermethylation and repression of the expression of genes encoding ripening transcription factors and rate-limiting enzymes of key biochemical processes such as carotenoid synthesis. Our data demonstrate that active DNA demethylation is central to the control of ripening in tomato.

A DEMETER-like DNA demethylase governs tomato fruit ripening

PubMed Central

Liu, Ruie; How-Kit, Alexandre; Stammitti, Linda; Teyssier, Emeline; Rolin, Dominique; Mortain-Bertrand, Anne; Halle, Stefanie; Liu, Mingchun; Kong, Junhua; Wu, Chaoqun; Degraeve-Guibault, Charlotte; Chapman, Natalie H.; Maucourt, Mickael; Hodgman, T. Charlie; Tost, Jörg; Bouzayen, Mondher; Hong, Yiguo; Seymour, Graham B.; Giovannoni, James J.; Gallusci, Philippe

2015-01-01

In plants, genomic DNA methylation which contributes to development and stress responses can be actively removed by DEMETER-like DNA demethylases (DMLs). Indeed, in Arabidopsis DMLs are important for maternal imprinting and endosperm demethylation, but only a few studies demonstrate the developmental roles of active DNA demethylation conclusively in this plant. Here, we show a direct cause and effect relationship between active DNA demethylation mainly mediated by the tomato DML, SlDML2, and fruit ripening— an important developmental process unique to plants. RNAi SlDML2 knockdown results in ripening inhibition via hypermethylation and repression of the expression of genes encoding ripening transcription factors and rate-limiting enzymes of key biochemical processes such as carotenoid synthesis. Our data demonstrate that active DNA demethylation is central to the control of ripening in tomato. PMID:26261318

The role of alternative oxidase in tomato fruit ripening and its regulatory interaction with ethylene

PubMed Central

Lin, Hong-Hui

2012-01-01

Although the alternative oxidase (AOX) has been proposed to play a role in fruit development, the function of AOX in fruit ripening is unclear. To gain further insight into the role of AOX in tomato fruit ripening, transgenic tomato plants 35S-AOX1a and 35S-AOX-RNAi were generated. Tomato plants with reduced LeAOX levels exhibited retarded ripening; reduced carotenoids, respiration, and ethylene production; and the down-regulation of ripening-associated genes. Moreover, no apparent respiratory climacteric occurred in the AOX-reduced tomato fruit, indicating that AOX might play an important role in climacteric respiration. In contrast, the fruit that overexpressed LeAOX1a accumulated more lycopene, though they displayed a similar pattern of ripening to wild-type fruit. Ethylene application promoted fruit ripening and anticipated ethylene production and respiration, including the alternative pathway respiration. Interestingly, the transgenic plants with reduced LeAOX levels failed to ripen after 1-methylcyclopropene (1-MCP) treatment, while such inhibition was notably less effective in 35S-AOX1a fruit. These findings indicate that AOX is involved in respiratory climacteric and ethylene-mediated fruit ripening of tomato. PMID:22915749

76 FR 37053 - Notice of Request for Extension of Approval of an Information Collection; Importation of Tomatoes...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-24

... Collection; Importation of Tomatoes From Souss-Massa-Draa, Morocco AGENCY: Animal and Plant Health Inspection... with regulations for the importation of tomatoes from Souss-Massa-Draa, Morocco. DATES: We will...: For information on regulations for the importation of tomatoes from Souss-Massa-Draa, Morocco, contact...

The sugar transporter inventory of tomato: genome-wide identification and expression analysis.

PubMed

Reuscher, Stefan; Akiyama, Masahito; Yasuda, Tomohide; Makino, Haruko; Aoki, Koh; Shibata, Daisuke; Shiratake, Katsuhiro

2014-06-01

The mobility of sugars between source and sink tissues in plants depends on sugar transport proteins. Studying the corresponding genes allows the manipulation of the sink strength of developing fruits, thereby improving fruit quality for human consumption. Tomato (Solanum lycopersicum) is both a major horticultural crop and a model for the development of fleshy fruits. In this article we provide a comprehensive inventory of tomato sugar transporters, including the SUCROSE TRANSPORTER family, the SUGAR TRANSPORTER PROTEIN family, the SUGAR FACILITATOR PROTEIN family, the POLYOL/MONOSACCHARIDE TRANSPORTER family, the INOSITOL TRANSPORTER family, the PLASTIDIC GLUCOSE TRANSLOCATOR family, the TONOPLAST MONOSACCHARIDE TRANSPORTER family and the VACUOLAR GLUCOSE TRANSPORTER family. Expressed sequence tag (EST) sequencing and phylogenetic analyses established a nomenclature for all analyzed tomato sugar transporters. In total we identified 52 genes in tomato putatively encoding sugar transporters. The expression of 29 sugar transporter genes in vegetative tissues and during fruit development was analyzed. Several sugar transporter genes were expressed in a tissue- or developmental stage-specific manner. This information will be helpful to better understand source to sink movement of photoassimilates in tomato. Identification of fruit-specific sugar transporters might be a first step to find novel genes contributing to tomato fruit sugar accumulation. © The Author 2014. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Genetic characterization of Italian tomato varieties and their traceability in tomato food products-Sardaro-2012-Food Science & Nutrition-Wiley Online Library

PubMed Central

Sardaro, Maria Luisa Savo; Marmiroli, Marta; Maestri, Elena; Marmiroli, Nelson

2013-01-01

Genetic diversity underlies the improvement of crops by plant breeding. Landraces of tomato (Solanum lycopersicum L.) can contain valuable alleles not common in modern germplasms. The aim was to measure genetic diversity present in 47 most common tomato varieties grown in Italy, 35 were varieties used for processing and 12 were landraces considered “salad varieties”. Furthermore, we demonstrated the possibility that the variety traceability can be extended through the entire production chain. Diversity was measured using 11 microsatellite markers and 94 genotypes. Among the markers used, a total of 48 alleles were detected. A dendrogram based on total microsatellite polymorphism grouped 47 varieties into three major clusters at 0.75 similarity coefficient, differentiating the modern varieties from tomatoes landraces. The DNA markers developed confirmed the possibility to support the genotype identification all along the tomato production chain. The number of alleles and genotypes identified in the present work is the largest considering papers on food traceability. PMID:24804014

Genetic characterization of Italian tomato varieties and their traceability in tomato food products-Sardaro-2012-Food Science & Nutrition-Wiley Online Library.

PubMed

Sardaro, Maria Luisa Savo; Marmiroli, Marta; Maestri, Elena; Marmiroli, Nelson

2013-01-01

Genetic diversity underlies the improvement of crops by plant breeding. Landraces of tomato (Solanum lycopersicum L.) can contain valuable alleles not common in modern germplasms. The aim was to measure genetic diversity present in 47 most common tomato varieties grown in Italy, 35 were varieties used for processing and 12 were landraces considered "salad varieties". Furthermore, we demonstrated the possibility that the variety traceability can be extended through the entire production chain. Diversity was measured using 11 microsatellite markers and 94 genotypes. Among the markers used, a total of 48 alleles were detected. A dendrogram based on total microsatellite polymorphism grouped 47 varieties into three major clusters at 0.75 similarity coefficient, differentiating the modern varieties from tomatoes landraces. The DNA markers developed confirmed the possibility to support the genotype identification all along the tomato production chain. The number of alleles and genotypes identified in the present work is the largest considering papers on food traceability.

Silencing SlMED18, tomato Mediator subunit 18 gene, restricts internode elongation and leaf expansion.

PubMed

Wang, Yunshu; Hu, Zongli; Zhang, Jianling; Yu, XiaoHui; Guo, Jun-E; Liang, Honglian; Liao, Changguang; Chen, Guoping

2018-02-19

Mediator complex, a conserved multi-protein, is necessary for controlling RNA polymerase II (Pol II) transcription in eukaryotes. Given little is known about them in tomato, a tomato Mediator subunit 18 gene was isolated and named SlMED18. To further explore the function of SlMED18, the transgenic tomato plants targeting SlMED18 by RNAi-mediated gene silencing were generated. The SlMED18-RNAi lines exhibited multiple developmental defects, including smaller size and slower growth rate of plant and significantly smaller compound leaves. The contents of endogenous bioactive GA 3 in SlMED18 silenced lines were slightly less than that in wild type. Furthermore, qRT-PCR analysis indicated that expression of gibberellins biosynthesis genes such as SlGACPS and SlGA20x2, auxin transport genes (PIN1, PIN4, LAX1 and LAX2) and several key regulators, KNOX1, KNOX2, PHAN and LANCEOLATE(LA), which involved in the leaf morphogenesis were significantly down-regulated in SlMED18-RNAi lines. These results illustrated that SlMED18 plays an essential role in regulating plant internode elongation and leaf expansion in tomato plants and it acts as a key positive regulator of gibberellins biosynthesis and signal transduction as well as auxin proper transport signalling. These findings are the basis for understanding the function of the individual Mediator subunits in tomato.

High species richness of native pollinators in Brazilian tomato crops.

PubMed

Silva-Neto, C M; Bergamini, L L; Elias, M A S; Moreira, G L; Morais, J M; Bergamini, B A R; Franceschinelli, E V

2017-01-01

Pollinators provide an essential service to natural ecosystems and agriculture. In tomatoes flowers, anthers are poricidal, pollen may drop from their pore when flowers are shaken by the wind. However, bees that vibrate these anthers increase pollen load on the stigma and in fruit production. The present study aimed to identify the pollinator richness of tomato flowers and investigate their morphological and functional traits related to the plant-pollinator interaction in plantations of Central Brazil. The time of anthesis, flower duration, and the number and viability of pollen grains and ovules were recorded. Floral visitors were observed and collected. Flower buds opened around 6h30 and closed around 18h00. They reopened on the following day at the same time in the morning, lasting on average 48 hours. The highest pollen availability occurred during the first hours of anthesis. Afterwards, the number of pollen grains declined, especially between 10h00 to 12h00, which is consistent with the pollinator visitation pattern. Forty bee species were found in the tomato fields, 30 of which were considered pollinators. We found that during the flowering period, plants offered an enormous amount of pollen to their visitors. These may explain the high richness and amount of bees that visit the tomato flowers in the study areas. The period of pollen availability and depletion throughout the day overlapped with the bees foraging period, suggesting that bees are highly effective in removing pollen grains from anthers. Many of these grains probably land on the stigma of the same flower, leading to self-pollination and subsequent fruit development. Native bees (Exomalopsis spp.) are effective pollinators of tomato flowers and are likely to contribute to increasing crop productivity. On the other hand, here tomato flowers offer large amounts of pollen resource to a high richness and amount of bees, showing a strong plant-pollinator interaction in the study agroecosystem.

Abscisic acid triggers whole-plant and fruit-specific mechanisms to increase fruit calcium uptake and prevent blossom end rot development in tomato fruit.

PubMed

de Freitas, Sergio Tonetto; Shackel, Kenneth A; Mitcham, Elizabeth J

2011-05-01

Calcium (Ca) uptake into fruit and leaves is dependent on xylemic water movement, and hence presumably driven by transpiration and growth. High leaf transpiration is thought to restrict Ca movement to low-transpiring tomato fruit, which may increase fruit susceptibility to the Ca-deficiency disorder, blossom end rot (BER). The objective of this study was to analyse the effect of reduced leaf transpiration in abscisic acid (ABA)-treated plants on fruit and leaf Ca uptake and BER development. Tomato cultivars Ace 55 (Vf) and AB2 were grown in a greenhouse environment under Ca-deficit conditions and plants were treated weekly after pollination with water (control) or 500 mg l(-1) ABA. BER incidence was completely prevented in the ABA-treated plants and reached values of 30-45% in the water-treated controls. ABA-treated plants had higher stem water potential, lower leaf stomatal conductance, and lower whole-plant water loss than water-treated plants. ABA treatment increased total tissue and apoplastic water-soluble Ca concentrations in the fruit, and decreased Ca concentrations in leaves. In ABA-treated plants, fruit had a higher number of Safranin-O-stained xylem vessels at early stages of growth and development. ABA treatment reduced the phloem/xylem ratio of fruit sap uptake. The results indicate that ABA prevents BER development by increasing fruit Ca uptake, possibly by a combination of whole-plant and fruit-specific mechanisms.

Expression of ORF2 partial gene of hepatitis E virus in tomatoes and immunoactivity of expression products.

PubMed

Ma, Ying; Lin, Shun-Quan; Gao, Yi; Li, Mei; Luo, Wen-Xin; Zhang, Jun; Xia, Ning-Shao

2003-10-01

To transfer hepatitis E virus (HEV) ORF2 partial gene to tomato plants, to investigate its expression in transformants and the immunoactivity of expression products, and to explore the feasibility of developing a new type of plant-derived HEV oral vaccine. Plant binary expression vector p1301E2, carrying a fragment of HEV open reading frame-2 (named HEV-E2), was constructed by linking the fragment to a constitutive CaMV35s promoter and nos terminator, then directly introduced into Agrobacterium tumefaciens EHA105. With leaf-disc method, tomato plants medicated by EHA105 were transformed and hygromycin-resistant plantlets were obtained in selective medium containing hygromycin. The presence and integration of foreign DNA in transgenic tomato genome were confirmed by Gus gene expression, PCR amplification and Southern dot blotting. The immunoactivity of recombinant protein extracted from transformed plants was examined by enzyme-linked immunosorbant assay (ELISA) using a monoclonal antibody specifically against HEV. ELISA was also used to estimate the recombinant protein content in leaves and fruits of the transformants. Seven positive lines of HEV-E2-transgenic tomato plants confirmed by PCR and Southern blotting were obtained and the immunoactivity of recombinant protein could be detected in extracts of transformants. The expression levels of recombinant protein were 61.22 ng/g fresh weight in fruits and 6.37-47.9 ng/g fresh weight in leaves of the transformants. HEV-E2 gene was correctly expressed in transgenic tomatoes and the recombinant antigen derived from them has normal immunoactivity. Transgenic tomatoes may hold a good promise for producing a new type of low-cost oral vaccine for hepatitis E virus.

Genomic analyses provide insights into the history of tomato breeding.

PubMed

Lin, Tao; Zhu, Guangtao; Zhang, Junhong; Xu, Xiangyang; Yu, Qinghui; Zheng, Zheng; Zhang, Zhonghua; Lun, Yaoyao; Li, Shuai; Wang, Xiaoxuan; Huang, Zejun; Li, Junming; Zhang, Chunzhi; Wang, Taotao; Zhang, Yuyang; Wang, Aoxue; Zhang, Yancong; Lin, Kui; Li, Chuanyou; Xiong, Guosheng; Xue, Yongbiao; Mazzucato, Andrea; Causse, Mathilde; Fei, Zhangjun; Giovannoni, James J; Chetelat, Roger T; Zamir, Dani; Städler, Thomas; Li, Jingfu; Ye, Zhibiao; Du, Yongchen; Huang, Sanwen

2014-11-01

The histories of crop domestication and breeding are recorded in genomes. Although tomato is a model species for plant biology and breeding, the nature of human selection that altered its genome remains largely unknown. Here we report a comprehensive analysis of tomato evolution based on the genome sequences of 360 accessions. We provide evidence that domestication and improvement focused on two independent sets of quantitative trait loci (QTLs), resulting in modern tomato fruit ∼100 times larger than its ancestor. Furthermore, we discovered a major genomic signature for modern processing tomatoes, identified the causative variants that confer pink fruit color and precisely visualized the linkage drag associated with wild introgressions. This study outlines the accomplishments as well as the costs of historical selection and provides molecular insights toward further improvement.

Genome-wide analysis of histone modifiers in tomato: gaining an insight into their developmental roles.

PubMed

Aiese Cigliano, Riccardo; Sanseverino, Walter; Cremona, Gaetana; Ercolano, Maria R; Conicella, Clara; Consiglio, Federica M

2013-01-28

Histone post-translational modifications (HPTMs) including acetylation and methylation have been recognized as playing a crucial role in epigenetic regulation of plant growth and development. Although Solanum lycopersicum is a dicot model plant as well as an important crop, systematic analysis and expression profiling of histone modifier genes (HMs) in tomato are sketchy. Based on recently released tomato whole-genome sequences, we identified in silico 32 histone acetyltransferases (HATs), 15 histone deacetylases (HDACs), 52 histone methytransferases (HMTs) and 26 histone demethylases (HDMs), and compared them with those detected in Arabidopsis (Arabidopsis thaliana), maize (Zea mays) and rice (Oryza sativa) orthologs. Comprehensive analysis of the protein domain architecture and phylogeny revealed the presence of non-canonical motifs and new domain combinations, thereby suggesting for HATs the existence of a new family in plants. Due to species-specific diversification during evolutionary history tomato has fewer HMs than Arabidopsis. The transcription profiles of HMs within tomato organs revealed a broad functional role for some HMs and a more specific activity for others, suggesting key HM regulators in tomato development. Finally, we explored S. pennellii introgression lines (ILs) and integrated the map position of HMs, their expression profiles and the phenotype of ILs. We thereby proved that the strategy was useful to identify HM candidates involved in carotenoid biosynthesis in tomato fruits. In this study, we reveal the structure, phylogeny and spatial expression of members belonging to the classical families of HMs in tomato. We provide a framework for gene discovery and functional investigation of HMs in other Solanaceae species.

Overexpression of plum auxin receptor PslTIR1 in tomato alters plant growth, fruit development and fruit shelf-life characteristics.

PubMed

El-Sharkawy, I; Sherif, S; El Kayal, W; Jones, B; Li, Z; Sullivan, A J; Jayasankar, Subramanian

2016-02-29

TIR1-like proteins are F-box auxin receptors. Auxin binding to the F-box receptor proteins promotes the formation of SCF(TIR1) ubiquitin ligase complex that targets the auxin repressors, Aux/IAAs, for degradation via the ubiquitin/26S proteasome pathway. The release of auxin response factors (ARFs) from their Aux/IAA partners allows ARFs to mediate auxin-responsive changes in downstream gene transcription. In an attempt to understand the potential role of auxin during fruit development, a plum auxin receptor, PslTIR1, has previously been characterized at the cellular, biochemical and molecular levels, but the biological significance of this protein is still lacking. In the present study, tomato (Solanum lycopersicum) was used as a model to investigate the phenotypic and molecular changes associated with the overexpression of PslTIR1. The findings of the present study highlighted the critical role of PslTIR1 as positive regulator of auxin-signalling in coordinating the development of leaves and fruits. This was manifested by the entire leaf morphology of transgenic tomato plants compared to the wild-type compound leaf patterning. Moreover, transgenic plants produced parthenocarpic fruits, a characteristic property of auxin hypersensitivity. The autocatalytic ethylene production associated with the ripening of climacteric fruits was not significantly altered in transgenic tomato fruits. Nevertheless, the fruit shelf-life characteristics were affected by transgene presence, mainly through enhancing fruit softening rate. The short shelf-life of transgenic tomatoes was associated with dramatic upregulation of several genes encoding proteins involved in cell-wall degradation, which determine fruit softening and subsequent fruit shelf-life. The present study sheds light into the involvement of PslTIR1 in regulating leaf morphology, fruit development and fruit softening-associated ripening, but not autocatalytic ethylene production. The results demonstrate that auxin

An improved method for Agrobacterium rhizogenes-mediated transformation of tomato suitable for the study of arbuscular mycorrhizal symbiosis.

PubMed

Ho-Plágaro, Tania; Huertas, Raúl; Tamayo-Navarrete, María I; Ocampo, Juan A; García-Garrido, José M

2018-01-01

Solanum lycopersicum , an economically important crop grown worldwide, has been used as a model for the study of arbuscular mycorrhizal (AM) symbiosis in non-legume plants for several years and several cDNA array hybridization studies have revealed specific transcriptomic profiles of mycorrhizal tomato roots. However, a method to easily screen candidate genes which could play an important role during tomato mycorrhization is required. We have developed an optimized procedure for composite tomato plant obtaining achieved through Agrobacterium rhizogenes -mediated transformation. This protocol involves the unusual in vitro culture of composite plants between two filter papers placed on the culture media. In addition, we show that DsRed is an appropriate molecular marker for the precise selection of cotransformed tomato hairy roots . S. lycopersicum composite plant hairy roots appear to be colonized by the AM fungus Rhizophagus irregularis in a manner similar to that of normal roots, and a modified construct useful for localizing the expression of promoters putatively associated with mycorrhization was developed and tested. In this study, we present an easy, fast and low-cost procedure to study AM symbiosis in tomato roots.

Hexanoic acid is a resistance inducer that protects tomato plants against Pseudomonas syringae by priming the jasmonic acid and salicylic acid pathways.

PubMed

Scalschi, Loredana; Vicedo, Begonya; Camañes, Gemma; Fernandez-Crespo, Emma; Lapeña, Leonor; González-Bosch, Carmen; García-Agustín, Pilar

2013-05-01

Hexanoic acid-induced resistance (Hx-IR) is effective against several pathogens in tomato plants. Our study of the mechanisms implicated in Hx-IR against Pseudomonas syringae pv. tomato DC3000 suggests that hexanoic acid (Hx) treatment counteracts the negative effect of coronatine (COR) and jasmonyl-isoleucine (JA-Ile) on the salicylic acid (SA) pathway. In Hx-treated plants, an increase in the expression of jasmonic acid carboxyl methyltransferase (JMT) and the SA marker genes PR1 and PR5 indicates a boost in this signalling pathway at the expense of a decrease in JA-Ile. Moreover, Hx treatment potentiates 12-oxo-phytodienoic acid accumulation, which suggests that this molecule might play a role per se in Hx-IR. These results support a positive relationship between the SA and JA pathways in Hx-primed plants. Furthermore, one of the mechanisms of virulence mediated by COR is stomatal re-opening on infection with P. syringae. In this work, we observed that Hx seems to inhibit stomatal opening in planta in the presence of COR, which suggests that, on infection in tomato, this treatment suppresses effector action to prevent bacterial entry into the mesophyll. © 2012 BSPP AND BLACKWELL PUBLISHING LTD.

A genome-scale metabolic network reconstruction of tomato (Solanum lycopersicum L.) and its application to photorespiratory metabolism.

PubMed

Yuan, Huili; Cheung, C Y Maurice; Poolman, Mark G; Hilbers, Peter A J; van Riel, Natal A W

2016-01-01

Tomato (Solanum lycopersicum L.) has been studied extensively due to its high economic value in the market, and high content in health-promoting antioxidant compounds. Tomato is also considered as an excellent model organism for studying the development and metabolism of fleshy fruits. However, the growth, yield and fruit quality of tomatoes can be affected by drought stress, a common abiotic stress for tomato. To investigate the potential metabolic response of tomato plants to drought, we reconstructed iHY3410, a genome-scale metabolic model of tomato leaf, and used this metabolic network to simulate tomato leaf metabolism. The resulting model includes 3410 genes and 2143 biochemical and transport reactions distributed across five intracellular organelles including cytosol, plastid, mitochondrion, peroxisome and vacuole. The model successfully described the known metabolic behaviour of tomato leaf under heterotrophic and phototrophic conditions. The in silico investigation of the metabolic characteristics for photorespiration and other relevant metabolic processes under drought stress suggested that: (i) the flux distributions through the mevalonate (MVA) pathway under drought were distinct from that under normal conditions; and (ii) the changes in fluxes through core metabolic pathways with varying flux ratio of RubisCO carboxylase to oxygenase may contribute to the adaptive stress response of plants. In addition, we improved on previous studies of reaction essentiality analysis for leaf metabolism by including potential alternative routes for compensating reaction knockouts. Altogether, the genome-scale model provides a sound framework for investigating tomato metabolism and gives valuable insights into the functional consequences of abiotic stresses. © 2015 The Authors.The Plant Journal published by Society for Experimental Biology and John Wiley & Sons Ltd.

Effect of Seed Treatment by Cold Plasma on the Resistance of Tomato to Ralstonia solanacearum (Bacterial Wilt)

PubMed Central

Jiang, Jiafeng; Lu, Yufang; Li, Jiangang; Li, Ling; He, Xin; Shao, Hanliang; Dong, Yuanhua

2014-01-01

This study investigated the effect of cold plasma seed treatment on tomato bacterial wilt, caused by Ralstonia solanacearum (R. solanacearum), and the regulation of resistance mechanisms. The effect of cold plasma of 80W on seed germination, plant growth, nutrient uptake, disease severity, hydrogen peroxide (H2O2) concentration and activities of peroxidase (POD; EC 1.11.1.7), polyphenol oxidase (PPO; EC 1.10.3.2) and phenylalanine ammonia lyase (PAL; EC 4.3.1.5) were examined in tomato plants. Plasma treatment increased tomato resistance to R. solanacearum with an efficacy of 25.0%. Plasma treatment significantly increased both germination and plant growth in comparison with the control treatment, and plasma-treated plants absorbed more calcium and boron than the controls. In addition, H2O2 levels in treated plants rose faster and reached a higher peak, at 2.579 µM gFW−1, 140% greater than that of the control. Activities of POD (421.3 U gFW−1), PPO (508.8 U gFW−1) and PAL (707.3 U gFW−1) were also greater in the treated plants than in the controls (103.0 U gFW−1, 166.0 U gFW−1 and 309.4 U gFW−1, respectively). These results suggest that plasma treatment affects the regulation of plant growth, H2O2 concentration, and POD, PPO and PAL activity in tomato, resulting in an improved resistance to R. solanacearum. Consequently, cold plasma seed treatment has the potential to control tomato bacterial wilt caused by R. solanacearum. PMID:24840508

Polyamines Attenuate Ethylene-Mediated Defense Responses to Abrogate Resistance to Botrytis cinerea in Tomato1[C][W][OA

PubMed Central

Nambeesan, Savithri; AbuQamar, Synan; Laluk, Kristin; Mattoo, Autar K.; Mickelbart, Michael V.; Ferruzzi, Mario G.; Mengiste, Tesfaye; Handa, Avtar K.

2012-01-01

Transgenic tomato (Solanum lycopersicum) lines overexpressing yeast spermidine synthase (ySpdSyn), an enzyme involved in polyamine (PA) biosynthesis, were developed. These transgenic lines accumulate higher levels of spermidine (Spd) than the wild-type plants and were examined for responses to the fungal necrotrophs Botrytis cinerea and Alternaria solani, bacterial pathogen Pseudomonas syringae pv tomato DC3000, and larvae of the chewing insect tobacco hornworm (Manduca sexta). The Spd-accumulating transgenic tomato lines were more susceptible to B. cinerea than the wild-type plants; however, responses to A. solani, P. syringae, or M. sexta were similar to the wild-type plants. Exogenous application of ethylene precursors, S-adenosyl-Met and 1-aminocyclopropane-1-carboxylic acid, or PA biosynthesis inhibitors reversed the response of the transgenic plants to B. cinerea. The increased susceptibility of the ySpdSyn transgenic tomato to B. cinerea was associated with down-regulation of gene transcripts involved in ethylene biosynthesis and signaling. These data suggest that PA-mediated susceptibility to B. cinerea is linked to interference with the functions of ethylene in plant defense. PMID:22128140

Characterization of rhizosphere bacteria for control of phytopathogenic fungi of tomato.

PubMed

Pastor, Nicolás; Carlier, Evelin; Andrés, Javier; Rosas, Susana B; Rovera, Marisa

2012-03-01

Fluorescent Pseudomonas spp., isolated from rhizosphere soil of tomato and pepper plants, were evaluated in vitro as potential antagonists of fungal pathogens. Strains were characterized using the API 20NE biochemical system, and tested against the causal agents of stem canker and leaf blight (Alternaria alternata f. sp. lycopersici), southern blight (Sclerotium rolfsii Sacc.), and root rot (Fusarium solani). To this end, dual culture antagonism assays were carried out on 25% Tryptic Soy Agar, King B medium, and Potato Dextrose Agar to determine the effect of the strains on mycelial growth of the pathogens. The effect of two concentrations of FeCl(3) on antagonism against Alternaria alternata f. sp. lycopersici was also tested. In addition, strains were screened for ability to produce exoenzymes and siderophores. Finally, the selected Pseudomonas strain, PCI2, was evaluated for effect on tomato seedling development and as a potential candidate for controlling tomato damping-off caused by Sclerotium rolfsii Sacc., under growth chamber conditions. All strains significantly inhibited Alternaria alternata f. sp. lycopersici, particularly in 25% TSA medium. Antagonistic effect on Sclerotium rolfsii Sacc. and Fusarium solani was greater on King B medium. Protease was produced by 30% of the strains, but no strains produced cellulase or chitinase. Growth chamber studies resulted in significant increases in plant stand as well as in root dry weight. PCI2 was able to establish and survive in tomato plants rhizosphere after 40 days following planting of bacterized seeds. Copyright © 2011 Elsevier Ltd. All rights reserved.

The developmental outcomes of P0-mediated ARGONAUTE destabilization in tomato.

PubMed

Hendelman, Anat; Kravchik, Michael; Stav, Ran; Zik, Moriyah; Lugassi, Nitsan; Arazi, Tzahi

2013-01-01

The plant protein ARGONAUTE1 (AGO1) functions in multiple RNA-silencing pathways, including those of microRNAs, key regulators of growth and development. Genetic analysis of ago1 mutants with informative defects has provided valuable insights into AGO1's biological functions. Tomato encodes two AGO1 homologs (SlAGO1s), but mutants have not been described to date. To analyze SlAGO1s' involvement in development, we confirmed that both undergo decay in the presence of the Polerovirus silencing suppressor P0 and produce a transgenic responder line (OP:P0HA) that, upon transactivation, expresses P0 C-terminally fused to a hemagglutinin (HA) tag (P0HA) and destabilizes SlAGO1s at the site of expression. By crossing OP:P0HA with a battery of driver lines, constitutive as well as organ- and stage-specific SlAGO1 downregulation was induced in the F1 progeny. Activated plants exhibited various developmental phenotypes that partially overlapped with those of Arabidopsis ago1 mutants. Plants that constitutively expressed P0HA had reduced SlAGO1 levels and increased accumulation of miRNA targets, indicating compromised SlAGO1-mediated silencing. Consistent with this, they exhibited pleiotropic morphological defects and their growth was arrested post-germination. Transactivation of P0HA in young leaf and floral organ primordia dramatically modified corresponding organ morphology, including the radialization of leaflets, petals and anthers, suggesting that SlAGO1s' activities are required for normal lateral organ development and polarity. Overall, our results suggest that the OP:P0HA responder line can serve as a valuable tool to suppress SlAGO1 silencing pathways in tomato. The suppression of additional SlAGOs by P0HA and its contribution to the observed phenotypes awaits investigation.

Response of tomatoes to ozone, sulphur dioxide, and infection by Pratylenchus penetrans

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shew, B.B.; Reinert, R.A.; Barker, K.R.

1982-01-01

Tomato plants (Lycopersicon esculentum 'Walter') were inoculated with initial population densities of Pratylenchus penetrans ranging 0-4000 nematodes per pot and were repeatedly exposed to ozone (O/sub 3/). Exposures to charcoal-filtered air served as controls. Decreases in dry weights of plant parts excised from tomato plants exposed to 0.2 ..mu..l O/sub 3/ per liter of air added to the decrease in dry weight caused by exposure to sulfur dioxide (SO/sub 2/) at 0.2 ..mu..l/L of air adequately predicted the decrease in dry weight of tomato plants caused by exposure to 0.2 ..mu..l O/sub 3/ + 0.2 ..mu..l SO/sub 2/ per litermore » of air. When 0.2 ..mu..l O/sub 3/ and 0.8 ..mu..l SO/sub 2/ per liter of air were present in mixture, they acted antagonistically and caused less change in leaf and shoot dry weight than could be predicted by the main effects of O/sub 3/ or SO/sub 2/. The presence of P. penetrans attacking the roots enhanced the negative effects of O/sub 3/ + SO/sub 2/ on leaf growth (dry weight), but suppressed the inhibitory effects of O/sub 3/ + SO/sub 2/ on auxillary shoot dry weight. Treatments containing 0.8 ..mu..l SO/sub 2/ per liter of air reduced tomato fruit weight, but the amount of reduction was antagonized by the presence of O/sub 3/.« less

Paraoxonase 1 Q192R (PON1-192) polymorphism is associated with reduced lipid peroxidation in healthy young men on a low-carotenoid diet supplemented with tomato juice.

PubMed

Bub, Achim; Barth, Stephan W; Watzl, Bernhard; Briviba, Karlis; Rechkemmer, Gerhard

2005-03-01

The HDL-bound enzyme paraoxonase (PON) protects LDL from oxidation and may therefore attenuate the development of atherosclerosis. We examined the effect of tomato and carrot juice consumption on PON1 activity and lipid peroxidation in healthy young volunteers with different PON1-192 genotypes (Q/R substitution at position 192). In this randomized cross-over study twenty-two healthy, non-smoking men on a low-carotenoid diet received 330 ml/d tomato juice (37.0 mg lycopene, 1.6 mg beta-carotene) or carrot juice (27.1 mg beta-carotene, 13.1 mg alpha-carotene) for 2 weeks. Intervention periods were preceded by 2-week low-carotenoid intake. We determined the PON1-192 genotype by restriction fragment length polymorphism-polymerase chain reaction (RFLP-PCR) and measured ex vivo LDL oxidation (lag time), plasma malondialdehyde and PON1 activity at the beginning and end of each intervention period. At baseline, lag time was higher (P<0.05) in QQ (111 (sd 9) min) than in QR/RR subjects (101 (sd 8) min). Neither tomato nor carrot juice consumption had significant effects on PON1 activity. However, tomato juice consumption reduced (P<0.05) plasma malondialdehyde in QR/RR (Delta: -0.073 (sd 0.11) micromol/l) as compared to QQ subjects (Delta:+0.047 (sd 0.13) micromol/l). Carrot juice had no significant effect on malondialdehyde irrespective of the PON1-192 genotype. Male volunteers with the QR/RR genotype showed an increased lipid peroxidation at baseline. Although tomato and carrot juice fail to affect PON1 activity, tomato juice intake reduced lipid peroxidation in healthy volunteers carrying the R-allele of the PON1-192 genotype and could thus contribute to CVD risk reduction in these individuals.

The symbiosis with the arbuscular mycorrhizal fungus Rhizophagus irregularis drives root water transport in flooded tomato plants.

PubMed

Calvo-Polanco, Monica; Molina, Sonia; Zamarreño, Angel María; García-Mina, Jose María; Aroca, Ricardo

2014-05-01

It is known that the presence of arbuscular mycorrhizal fungi within the plant roots enhances the tolerance of the host plant to different environmental stresses, although the positive effect of the fungi in plants under waterlogged conditions has not been well studied. Tolerance of plants to flooding can be achieved through different molecular, physiological and anatomical adaptations, which will affect their water uptake capacity and therefore their root hydraulic properties. Here, we investigated the root hydraulic properties under non-flooded and flooded conditions in non-mycorrhizal tomato plants and plants inoculated with the arbuscular mycorrhizal fungus Rhizophagus irregularis. Only flooded mycorrhizal plants increased their root hydraulic conductivity, and this effect was correlated with a higher expression of the plant aquaporin SlPIP1;7 and the fungal aquaporin GintAQP1. There was also a higher abundance of the PIP2 protein phoshorylated at Ser280 in mycorrhizal flooded plants. The role of plant hormones (ethylene, ABA and IAA) in root hydraulic properties was also taken into consideration, and it was concluded that, in mycorrhizal flooded plants, ethylene has a secondary role regulating root hydraulic conductivity whereas IAA may be the key hormone that allows the enhancement of root hydraulic conductivity in mycorrhizal plants under low oxygen conditions.

Growth and Tomato Nutrition Content with Bandotan (Ageratum Conyzoides L) Bokashi Applied

NASA Astrophysics Data System (ADS)

Anhar, A.; Junialdi, R.; Zein, A.; Advinda, L.; Leilani, I.

2018-04-01

Bandotan (A.conyzoides) is one of the most common weeds in dry land. Weeds can reduce the results of a variety of crops. On the contrary, the use of this weed as the organic material would be able to increase the nutrient content of the soil. The problem is, the decomposition of this weed is naturally longer than the process in the form of Bokashi. This study aims to determine the effect of Bandotan applied in the form of Bokashi on growth and nutrient content of tomato plants. This study was an experimental study and completely randomized design was used with 5 treatments and 3 replications. The treatment were rate of bandotan bokashi those 100, 120, 140, 160 g / polybag and 0,6g NPK / polybag as a control. The research was conducted in the Screen House of Biology Department, Faculty of Mathematic and Sciences, Universitas Negeri Padang. Tomato growth observed was high, wet weight, biomass and weight of the fruit. While the nutritional quality of tomatoes was vitamin C and A. Data were analyzed using ANOVA and a further test DNMRT at 5% level. The results showed that bokhasi bandotan 120g / polybag give best effect to the weight of tomatoes. However, bandotan bokashi do not give effect to the high, wet weight, biomass, vitamin C and vitamin A of tomato. Bokashi bandotan can be utilized as a substitute for synthetic fertilizer NPK for tomato plants.

Involvement of Trichoderma harzianum Epl-1 Protein in the Regulation of Botrytis Virulence- and Tomato Defense-Related Genes.

PubMed

Gomes, Eriston V; Ulhoa, Cirano J; Cardoza, Rosa E; Silva, Roberto N; Gutiérrez, Santiago

2017-01-01

Several Trichoderma spp. are well known for their ability to: (i) act as important biocontrol agents against phytopathogenic fungi; (ii) function as biofertilizers; (iii) increase the tolerance of plants to biotic and abiotic stresses; and (iv) induce plant defense responses via the production and secretion of elicitor molecules. In this study, we analyzed the gene-regulation effects of Trichoderma harzianum Epl-1 protein during the interactions of mutant Δ epl-1 or wild-type T. harzianum strains with: (a) the phytopathogen Botrytis cinerea and (b) with tomato plants, on short (24 h hydroponic cultures) and long periods (4-weeks old plants) after Trichoderma inoculation. Our results indicate that T. harzianum Epl-1 protein affects the in vitro expression of B. cinerea virulence genes, especially those involved in the botrydial biosynthesis ( BcBOT genes), during the mycoparasitism interaction. The tomato defense-related genes were also affected, indicating that Epl-1 is involved in the elicitation of the salicylic acid pathway. Moreover, Epl-1 also regulates the priming effect in host tomato plants and contributes to enhance the interaction with the host tomato plant during the early stage of root colonization.

Involvement of Trichoderma harzianum Epl-1 Protein in the Regulation of Botrytis Virulence- and Tomato Defense-Related Genes

PubMed Central

Gomes, Eriston V.; Ulhoa, Cirano J.; Cardoza, Rosa E.; Silva, Roberto N.; Gutiérrez, Santiago

2017-01-01

Several Trichoderma spp. are well known for their ability to: (i) act as important biocontrol agents against phytopathogenic fungi; (ii) function as biofertilizers; (iii) increase the tolerance of plants to biotic and abiotic stresses; and (iv) induce plant defense responses via the production and secretion of elicitor molecules. In this study, we analyzed the gene-regulation effects of Trichoderma harzianum Epl-1 protein during the interactions of mutant Δepl-1 or wild-type T. harzianum strains with: (a) the phytopathogen Botrytis cinerea and (b) with tomato plants, on short (24 h hydroponic cultures) and long periods (4-weeks old plants) after Trichoderma inoculation. Our results indicate that T. harzianum Epl-1 protein affects the in vitro expression of B. cinerea virulence genes, especially those involved in the botrydial biosynthesis (BcBOT genes), during the mycoparasitism interaction. The tomato defense-related genes were also affected, indicating that Epl-1 is involved in the elicitation of the salicylic acid pathway. Moreover, Epl-1 also regulates the priming effect in host tomato plants and contributes to enhance the interaction with the host tomato plant during the early stage of root colonization. PMID:28611802

A Role for APETALA1/FRUITFULL Transcription Factors in Tomato Leaf Development[C][W

PubMed Central

Burko, Yogev; Shleizer-Burko, Sharona; Yanai, Osnat; Shwartz, Ido; Zelnik, Iris Daphne; Jacob-Hirsch, Jasmine; Kela, Itai; Eshed-Williams, Leor; Ori, Naomi

2013-01-01

Flexible maturation rates underlie part of the diversity of leaf shape, and tomato (Solanum lycopersicum) leaves are compound due to prolonged organogenic activity of the leaf margin. The CINCINNATA -TEOSINTE BRANCHED1, CYCLOIDEA, PCF (CIN-TCP) transcription factor LANCEOLATE (LA) restricts this organogenic activity and promotes maturation. Here, we show that tomato APETALA1/FRUITFULL (AP1/FUL) MADS box genes are involved in tomato leaf development and are repressed by LA. AP1/FUL expression is correlated negatively with LA activity and positively with the organogenic activity of the leaf margin. LA binds to the promoters of the AP1/FUL genes MBP20 and TM4. Overexpression of MBP20 suppressed the simple-leaf phenotype resulting from upregulation of LA activity or from downregulation of class I knotted like homeobox (KNOXI) activity. Overexpression of a dominant-negative form of MBP20 led to leaf simplification and partly suppressed the increased leaf complexity of plants with reduced LA activity or increased KNOXI activity. Tomato plants overexpressing miR319, a negative regulator of several CIN-TCP genes including LA, flower with fewer leaves via an SFT-dependent pathway, suggesting that miR319-sensitive CIN-TCPs delay flowering in tomato. These results identify a role for AP1/FUL genes in vegetative development and show that leaf and plant maturation are regulated via partially independent mechanisms. PMID:23771895

Host-Induced Silencing of Pathogenicity Genes Enhances Resistance to Fusarium oxysporum Wilt in Tomato.

PubMed

Bharti, Poonam; Jyoti, Poonam; Kapoor, Priya; Sharma, Vandana; Shanmugam, V; Yadav, Sudesh Kumar

2017-08-01

This study presents a novel approach of controlling vascular wilt in tomato by RNAi expression directed to pathogenicity genes of Fusarium oxysporum f. sp. lycopersici. Vascular wilt of tomato caused by Fusarium oxysporum f. sp. lycopersici leads to qualitative and quantitative loss of the crop. Limitation in the existing control measures necessitates the development of alternative strategies to increase resistance in the plants against pathogens. Recent findings paved way to RNAi, as a promising method for silencing of pathogenicity genes in fungus and provided effective resistance against fungal pathogens. Here, two important pathogenicity genes FOW2, a Zn(II)2Cys6 family putative transcription regulator, and chsV, a putative myosin motor and a chitin synthase domain, were used for host-induced gene silencing through hairpinRNA cassettes of these genes against Fusarium oxysporum f. sp. lycopersici. HairpinRNAs were assembled in appropriate binary vectors and transformed into tomato plant targeting FOW2 and chsV genes, for two highly pathogenic strains of Fusarium oxysporum viz. TOFOL-IHBT and TOFOL-IVRI. Transgenic tomatoes were analyzed for possible attainment of resistance in transgenic lines against fungal infection. Eight transgenic lines expressing hairpinRNA cassettes showed trivial disease symptoms after 6-8 weeks of infection. Hence, the host-induced posttranscriptional gene silencing of pathogenicity genes in transgenic tomato plants has enhanced their resistance to vascular wilt disease caused by Fusarium oxysporum.

Effects of Thrips Density, Mode of Inoculation, and Plant Age on Tomato Spotted Wilt Virus Transmission in Peanut Plants.

PubMed

Shrestha, Anita; Sundaraj, Sivamani; Culbreath, Albert K; Riley, David G; Abney, Mark R; Srinivasan, Rajagopalbabu

2015-02-01

Spotted wilt caused by tomato spotted wilt virus (TSWV; family Bunyaviridae; genus Tospovirus) is a serious disease of peanut (Arachis hypogaea L.) in the southeastern United States. Peanut genotypes with field resistance to TSWV are effective in suppressing spotted wilt. All commercially available genotypes with field resistance to TSWV were developed through conventional breeding. As a part of the breeding process, peanut genotypes are regularly screened under field situations. Despite numerous advantages associated with field screening, it is often limited by inconsistent vector (thrips) and TSWV pressure. A greenhouse transmission protocol would aid in thorough screening of selected genotypes and conserve time. In this study, various parameters associated with TSWV transmission, including tobacco thrips, Frankliniella fusca (Hinds) density, mode of inoculation, and plant age, were evaluated. Greater incidences of TSWV infection were obtained with thrips-mediated inoculation when compared with mechanical inoculation. TSWV inoculation with three, five, and 10 thrips resulted in greater incidences of TSWV infection in plants than inoculation with one thrips. However, incidences of TSWV infection did not vary between plants inoculated with three, five, and 10 viruliferous thrips. With both thrips-mediated and mechanical inoculation methods, incidences of TSWV infection in 1-wk-old plants were greater than in 4-wk-old plants. TSWV copy numbers, as determined by qPCR, also decreased with plant age. Results suggest that using at least three thrips per plant and 1- to 2-wk-old plants would maximize TSWV infection in inoculated plants. © The Author 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Large-scale analysis of full-length cDNAs from the tomato (Solanum lycopersicum) cultivar Micro-Tom, a reference system for the Solanaceae genomics.

PubMed

Aoki, Koh; Yano, Kentaro; Suzuki, Ayako; Kawamura, Shingo; Sakurai, Nozomu; Suda, Kunihiro; Kurabayashi, Atsushi; Suzuki, Tatsuya; Tsugane, Taneaki; Watanabe, Manabu; Ooga, Kazuhide; Torii, Maiko; Narita, Takanori; Shin-I, Tadasu; Kohara, Yuji; Yamamoto, Naoki; Takahashi, Hideki; Watanabe, Yuichiro; Egusa, Mayumi; Kodama, Motoichiro; Ichinose, Yuki; Kikuchi, Mari; Fukushima, Sumire; Okabe, Akiko; Arie, Tsutomu; Sato, Yuko; Yazawa, Katsumi; Satoh, Shinobu; Omura, Toshikazu; Ezura, Hiroshi; Shibata, Daisuke

2010-03-30

The Solanaceae family includes several economically important vegetable crops. The tomato (Solanum lycopersicum) is regarded as a model plant of the Solanaceae family. Recently, a number of tomato resources have been developed in parallel with the ongoing tomato genome sequencing project. In particular, a miniature cultivar, Micro-Tom, is regarded as a model system in tomato genomics, and a number of genomics resources in the Micro-Tom-background, such as ESTs and mutagenized lines, have been established by an international alliance. To accelerate the progress in tomato genomics, we developed a collection of fully-sequenced 13,227 Micro-Tom full-length cDNAs. By checking redundant sequences, coding sequences, and chimeric sequences, a set of 11,502 non-redundant full-length cDNAs (nrFLcDNAs) was generated. Analysis of untranslated regions demonstrated that tomato has longer 5'- and 3'-untranslated regions than most other plants but rice. Classification of functions of proteins predicted from the coding sequences demonstrated that nrFLcDNAs covered a broad range of functions. A comparison of nrFLcDNAs with genes of sixteen plants facilitated the identification of tomato genes that are not found in other plants, most of which did not have known protein domains. Mapping of the nrFLcDNAs onto currently available tomato genome sequences facilitated prediction of exon-intron structure. Introns of tomato genes were longer than those of Arabidopsis and rice. According to a comparison of exon sequences between the nrFLcDNAs and the tomato genome sequences, the frequency of nucleotide mismatch in exons between Micro-Tom and the genome-sequencing cultivar (Heinz 1706) was estimated to be 0.061%. The collection of Micro-Tom nrFLcDNAs generated in this study will serve as a valuable genomic tool for plant biologists to bridge the gap between basic and applied studies. The nrFLcDNA sequences will help annotation of the tomato whole-genome sequence and aid in tomato functional

Factors Affecting Soil Microbial Community Structure in Tomato Cropping Systems

USDA-ARS?s Scientific Manuscript database

Soil and rhizosphere microbial communities in agroecosystems may be affected by soil, climate, plant species, and management. We identified some of the most important factors controlling microbial biomass and community structure in an agroecosystem utilizing tomato plants with the following nine tre...

Elucidating the functional role of endoreduplication in tomato fruit development

PubMed Central

Chevalier, Christian; Nafati, Mehdi; Mathieu-Rivet, Elodie; Bourdon, Matthieu; Frangne, Nathalie; Cheniclet, Catherine; Renaudin, Jean-Pierre; Gévaudant, Frédéric; Hernould, Michel

2011-01-01

Background Endoreduplication is the major source of endopolyploidy in higher plants. The process of endoreduplication results from the ability of cells to modify their classical cell cycle into a partial cell cycle where DNA synthesis occurs independently from mitosis. Despite the ubiquitous occurrence of the phenomenon in eukaryotic cells, the physiological meaning of endoreduplication remains vague,although several roles during plant development have been proposed, mostly related to cell differentiation and cell size determination. Scope Here recent advances in the knowledge of endoreduplication and fruit organogenesis are reviewed, focusing on tomato (Solanum lycopersicum) as a model, and the functional analyses of endoreduplication-associated regulatory genes in tomato fruit are described. Conclusions The cyclin-dependent kinase inhibitory kinase WEE1 and the anaphase promoting complex activator CCS52A both participate in the control of cell size and the endoreduplication process driving cell expansion during early fruit development in tomato. Moreover the fruit-specific functional analysis of the tomato CDK inhibitor KRP1 reveals that cell size and fruit size determination can be uncoupled from DNA ploidy levels, indicating that endoreduplication acts rather as a limiting factor for cell growth. The overall functional data contribute to unravelling the physiological role of endoreduplication in growth induction of fleshy fruits. PMID:21199834

Pollination of tomatoes by the stingless bee Melipona quadrifasciata and the honey bee Apis mellifera (Hymenoptera, Apidae).

PubMed

dos Santos, S A Bispo; Roselino, A C; Hrncir, M; Bego, L R

2009-06-30

The pollination effectiveness of the stingless bee Melipona quadrifasciata and the honey bee Apis mellifera was tested in tomato plots. The experiment was conducted in four greenhouses as well as in an external open plot in Ribeirão Preto, SP, Brazil. The tomato plants were exposed to visits by M. quadrifasciata in one greenhouse and to A. mellifera in another; two greenhouses were maintained without bees (controls) and an open field plot was exposed to pollinators in an area where both honey bee and stingless bee colonies are abundant. We counted the number of tomatoes produced in each plot. Two hundred tomatoes from each plot were weighed, their vertical and transversal circumferences were measured, and the seeds were counted. We collected 253 Chrysomelidae, 17 Halictidae, one Paratrigona sp, and one honey bee from the flowers of the tomato plants in the open area. The largest number of fruits (1414 tomatoes), the heaviest and largest tomatoes, and the ones with the most seed were collected from the greenhouse with stingless bees. Fruits cultivated in the greenhouse with honey bees had the same weight and size as those produced in one of the control greenhouses. The stingless bee, M. quadrifasciata, was significantly more efficient than honey bees in pollinating greenhouse tomatoes.

RNAi-mediated silencing of MAP kinase signalling genes (Fmk1, Hog1, and Pbs2) in Fusarium oxysporum reduces pathogenesis on tomato plants.

PubMed

Pareek, Manish; Rajam, Manchikatla Venkat

2017-09-01

Fusarium oxysporum is a soil-borne plant fungal pathogen, and causes colossal losses in several crop plants including tomato. Effective control measures include the use of harmful fungicides and resistant cultivars, but these methods have shown limited success. Conventional methods to validate fungal pathogenic genes are labour intensive. Therefore, an alternative strategy is required to efficiently characterize unknown pathogenic genes. RNA interference (RNAi) has emerged as a potential tool to functionally characterize novel fungal pathogenic genes and also to control fungal diseases. Here, we report an efficient method to produce stable RNAi transformants of F. oxysporum using Agrobacterium-mediated transformation (AMT). We have transformed F. oxysporum spores using RNAi constructs of Fmk1, Hog1, and Pbs2 MAP kinase signalling genes. Fmk1 RNAi fungal transformants showed loss of surface hydrophobicity, reduced invasive growth on tomato fruits and hypo-virulence on tomato seedlings. Hog1 and Pbs2 RNAi transformants showed altered conidial size, and reduced invasive growth and pathogenesis. These results showed that AMT using RNAi constructs is an effective approach for dissecting the role of genes involved in pathogenesis in F. oxysporum and this could be extended for other fungal systems. The obtained knowledge can be easily translated for developing fungal resistant crops by RNAi. Copyright © 2017 British Mycological Society. Published by Elsevier Ltd. All rights reserved.

Effects of Extremely High ’G’ Acceleration Forces on NASA’s Control and Space Exposed Tomato Seeds