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Sample records for pv tomato strains

  1. Genome Sequences of Two Pseudomonas syringae pv. tomato Race 1 Strains, Isolated from Tomato Fields in California

    OpenAIRE

    Thapa, Shree P.; Coaker, Gitta

    2016-01-01

    Pseudomonas syringae pv. tomato race 1 strains have evolved to overcome genetic resistance in tomato. Here, we present the draft genome sequences of two race 1 P.?syringae pv. tomato strains, A9 and 407, isolated from diseased tomato plants in California.

  2. Assessment of strains of Pseudomonas syringae pv. tomato from Tanzania for resistance to copper and streptomycin

    DEFF Research Database (Denmark)

    Shenge, K.C.; Wydra, K.; Mabagala, M.B.

    2008-01-01

    Fifty-six strains of Pseudomonas syringae pv. tomato (P.s. pv. tomato) were collected from tomato-producing areas in Tanzania and assessed for resistance to copper and antibiotics. The collection was done from three tomato-producing regions (Morogoro, Arusha and Iringa), representing three...... different ecological conditions in the country. After isolation and identification, the P. s. pv. tomato strains were grown on King's medium B (KB) amended with 20% copper sulphate (w/v). The strains were also assessed for resistance to antibiotics. Results indicated that there was widespread resistance...... strains of the pathogen were moderately resistant to copper sulphate, such that 54.0% of them were able to grow on the KB medium amended with 20% (w/v) of the copper compound....

  3. 40 CFR 180.1261 - Xanthomonas campestris pv. vesicatoria and Pseudomonas syringae pv. tomato specific Bacteriophages.

    Science.gov (United States)

    2010-07-01

    ... and Pseudomonas syringae pv. tomato specific Bacteriophages. 180.1261 Section 180.1261 Protection of.... vesicatoria and Pseudomonas syringae pv. tomato specific Bacteriophages. An exemption from the requirement of... syringae pv. tomato specific bacteriophages in or on pepper and tomato. [74 FR 26536, June 3, 2009] ...

  4. A rapid seedling resistance assay identifies wild tomato lines that are resistant to Psuedomonas syringe pv. tomato race 1

    Science.gov (United States)

    Bacterial speck caused by Pseudomonas syringae has historically been controlled by the Pto/Prf gene cluster. Emerging strains like P. syringae pv. tomato race 1 overcome resistance conferred by Pto/Prf, and can cause serious crop loss under appropriate environmental conditions. We developed a rapid ...

  5. Molecular characterization of Pseudomonas syringae pv. tomato isolates from Tanzania

    DEFF Research Database (Denmark)

    Shenge, K.C.; Stephan, D.; Mabagala, R. B.

    2008-01-01

    Bacterial speck caused by Pseudomonas syringae pv. tomato is an emerging disease of tomato in Tanzania. Following reports of outbreaks of the disease in many locations in Tanzania, 56 isolates of P. syringae pv. tomato were collected from four tomato- producing areas and characterized using...

  6. Identification of a Candidate Gene in Solanum habrochaites for Resistance to a Race 1 Strain of Pseudomonas syringae pv. tomato

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    Zhilong Bao

    2015-11-01

    Full Text Available Bacterial speck disease caused by pv. ( is a persistent problem on tomato ( L.. Resistance against race 0 strains is conferred by the Pto protein, which recognizes either of two pathogen effectors: AvrPto or AvrPtoB. However, current tomato varieties do not have resistance to the increasingly common race 1 strains, which lack these effectors. We identified accessions of S. Knapp & D. M. Spooner that are resistant to the race 1 strain T1. Genome sequence comparisons of T1 and two strains that are virulent on these accessions suggested that known microbe-associated molecular patterns (MAMPs or effectors are not involved in the resistance. We developed an F population from a cross between one T1-resistant accession, LA2109, and a susceptible tomato cultivar to investigate the genetic basis of this resistance. Linkage analysis using whole-genome sequence of 58 F plants identified quantitative trait loci (QTL, , in a 5.8-Mb region on chromosome 2, and , in a 52.4-Mb region on chromosome 8, which account for 24 and 26% of the phenotypic variability, respectively. High-resolution mapping of confirmed it contributed to T1 resistance and delimited it to a 1060-kb region containing 139 genes, including three encoding receptor-like proteins (RLPs and 17 encoding receptor-like protein kinases (RLKs. One RLK gene, Solyc02g072470, is a promising candidate for , as it is highly expressed in LA2109 and induced on treatment with MAMPs. might be useful for enhancing resistance to race 1 strains and its future characterization could provide insights into the plant immune system.

  7. First report of bacterial speck of tomato caused by Pseudomonas syringae pv. tomato race 1 in Portugal

    OpenAIRE

    Cruz, L.; Cruz, J.; Eloy, M.; Oliveira, Helena; Vaz, H.; Tenreiro, R.

    2010-01-01

    Protected and open field tomato crops are economically important for Portuguese agriculture. In 1983, Pseudomonas syringae pv. tomato (Okabe, 1933) Young, Dye & Wilkie, 1978 was first reported affecting protected crops (3) and then later under open field conditions (1). In the 2009 spring/summer season, several outbreaks of bacterial speck of tomato showing an unusual degree of severity were observed in open fields from the Tagus Valley Region

  8. Natural variation for responsiveness to flg22, flgII-28, and csp22 and Pseudomonas syringae pv. tomato in heirloom tomatoes.

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    Selvakumar Veluchamy

    Full Text Available Tomato (Solanum lycopersicum L. is susceptible to many diseases including bacterial speck caused by Pseudomonas syringae pv. tomato. Bacterial speck disease is a serious problem worldwide in tomato production areas where moist conditions and cool temperatures occur. To enhance breeding of speck resistant fresh-market tomato cultivars we identified a race 0 field isolate, NC-C3, of P. s. pv. tomato in North Carolina and used it to screen a collection of heirloom tomato lines for speck resistance in the field. We observed statistically significant variation among the heirloom tomatoes for their response to P. s. pv. tomato NC-C3 with two lines showing resistance approaching a cultivar that expresses the Pto resistance gene, although none of the heirloom lines have Pto. Using an assay that measures microbe-associated molecular pattern (MAMP-induced production of reactive oxygen species (ROS, we investigated whether the heirloom lines showed differential responsiveness to three bacterial-derived peptide MAMPs: flg22 and flgII-28 (from flagellin and csp22 (from cold shock protein. Significant differences were observed for MAMP responsiveness among the lines, although these differences did not correlate strongly with resistance or susceptibility to bacterial speck disease. The identification of natural variation for MAMP responsiveness opens up the possibility of using a genetic approach to identify the underlying loci and to facilitate breeding of cultivars with enhanced disease resistance. Towards this goal, we discovered that responsiveness to csp22 segregates as a single locus in an F2 population of tomato.

  9. Comparison of the complete genome sequences of Pseudomonassyringae pv. syringae B728a and pv. tomato DC3000.

    Energy Technology Data Exchange (ETDEWEB)

    Feil, Helene; Feil, William S.; Chain, Patrick; Larimer, Frank; DiBartolo, Genevieve; Copeland, Alex; Lykidis, Athanasios; Trong,Stephen; Nolan, Matt; Goltsman, Eugene; Thiel, James; Malfatti,Stephanie; Loper, Joyce E.; Lapidus, Alla; Detter, John C.; Land, Miriam; Richardson, Paul M.; Kyrpides, Nikos C.; Ivanova, Natalia; Lindow, StevenE.

    2005-04-01

    producing avariety of different symptoms depending on the host species and site ofinfection. For example, it causes leaf spot diseases that defoliateplants such as tomato, bean, soybean, trunk cankers, and so-called"blast" diseases on fruit, nut and ornamental species. Considerablevariation occurs both between and within different pathovars of P.syringae (1). Because of its importance as a plant pathogen, it has beenthe subject of much research, especially of its epidemiology andvirulence mechanisms (2). Pseudomonas syringae pv. syringae (Pss) strainB728a is typical of most strains of this pathovar in that it exhibits avery pronounced epiphytic phase on plants. Such strains achieve andmaintain large populations on healthy plants, where they are exposed tostressful conditions such as dryness and sunlight that are hostile tobacterial growth(2). Epiphytic Pss populations serve as inocula that cansubsequently invade plants and initiate disease. Pss strains are distinctfrom many P. syringae strains, such as P. syringae pv. tomato (Pst)strain DC3000, that poorly colonize the exterior of plants; these strainsmay be considered "endophytes" based on their ability to multiply mostlywithin the plant (3). True epiphytes such as Pss B728a often reachsurface populations of over 107 cells/g while strains such as Pst DC3000seldom exceed 105 cells/g (2, 3). Thus, these strains might be consideredto occupy different ends of the epiphytic/endophytic spectrum of plantcolonization as described by Beattie and Lindow (4). As a pathogen and anepiphyte, Pss B728a has evolved to exploit at least two distincthabitats: the leaf surface and apoplast. Because rapid changes intemperature, low water content, and incident solar radiation occur onleaf surfaces, it has been hypothesized that the epiphyte Pss B728aposseses more genes conferring environmental stress tolerance than theendophyte Pst DC3000 (4). Pss B728a also exhibits several traits such asice nucleation activity and SR production (2) that are

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

    Science.gov (United States)

    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.

  11. The plant pathogen Pseudomonas syringae pv. tomato is genetically monomorphic and under strong selection to evade tomato immunity.

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    Rongman Cai

    2011-08-01

    Full Text Available Recently, genome sequencing of many isolates of genetically monomorphic bacterial human pathogens has given new insights into pathogen microevolution and phylogeography. Here, we report a genome-based micro-evolutionary study of a bacterial plant pathogen, Pseudomonas syringae pv. tomato. Only 267 mutations were identified between five sequenced isolates in 3,543,009 nt of analyzed genome sequence, which suggests a recent evolutionary origin of this pathogen. Further analysis with genome-derived markers of 89 world-wide isolates showed that several genotypes exist in North America and in Europe indicating frequent pathogen movement between these world regions. Genome-derived markers and molecular analyses of key pathogen loci important for virulence and motility both suggest ongoing adaptation to the tomato host. A mutational hotspot was found in the type III-secreted effector gene hopM1. These mutations abolish the cell death triggering activity of the full-length protein indicating strong selection for loss of function of this effector, which was previously considered a virulence factor. Two non-synonymous mutations in the flagellin-encoding gene fliC allowed identifying a new microbe associated molecular pattern (MAMP in a region distinct from the known MAMP flg22. Interestingly, the ancestral allele of this MAMP induces a stronger tomato immune response than the derived alleles. The ancestral allele has largely disappeared from today's Pto populations suggesting that flagellin-triggered immunity limits pathogen fitness even in highly virulent pathogens. An additional non-synonymous mutation was identified in flg22 in South American isolates. Therefore, MAMPs are more variable than expected differing even between otherwise almost identical isolates of the same pathogen strain.

  12. Xanthomonads and other yellow-pigmented, Xanthomonas-like bacteria associated with tomato seeds in Tanzania

    DEFF Research Database (Denmark)

    Mbega, Ernest Rashid; Wulff, Ednar Gadelha; Mabagala, R.B.

    2012-01-01

    of Xanthomonas campestris pv. malvacearum, were pathogenic on tomato and pepper plants. Strains identified by Biolog as Sphingomonas sanguinis and Sphingomonas terrae also incited black rot symptoms on pepper leaves. However, bacterial strains belonging to the genus Stenotrophomonas, Chryseobacterium, Pantoea...... and Flavobacterium were not pathogenic on tomato and pepper. Phylogenetic analysis showed that strains of the genus Xanthomonas are more closely related to Stenotrophomonas and Pantoea compared to the other bacterial genera found in tomato seeds....

  13. Inducible Expression of the De-Novo Designed Antimicrobial Peptide SP1-1 in Tomato Confers Resistance to Xanthomonas campestris pv. vesicatoria.

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    Areli Herrera Diaz

    Full Text Available Antimicrobial peptides (AMPs are small peptides with less than 50 amino acids and are part of the innate immune response in almost all organisms, including bacteria, vertebrates, invertebrates and plants. AMPs are active against a broad-spectrum of pathogens. The inducible expression of AMPs in plants is a promising approach to combat plant pathogens with minimal negative side effects, such as phytotoxicity or infertility. In this study, inducible expression of the de-novo designed AMP SP1-1 in Micro Tom tomato protected tomato fruits against bacterial spot disease caused by Xanthomonas campestris pv. vesicatoria. The peptide SP1-1 was targeted to the apoplast which is the primary infection site for plant pathogens, by fusing SP1-1 peptide to the signal peptide RsAFP1 of radish (Raphanus sativus. The pathogen inducibility of the expression was enabled by using an optimized inducible 4XW2/4XS promoter. As a result, the tomato fruits of independently generated SP1-1 transgenic lines were significantly more resistant to X. campestris pv. vesicatoria than WT tomato fruits. In transgenic lines, bacterial infection was reduced up to 65% in comparison to the infection of WT plants. Our study demonstrates that the combination of the 4XW2/4XS cis-element from parsley with the synthetic antimicrobial peptide SP1-1 is a good alternative to protect tomato fruits against infections with X. campestris pv. vesicatoria.

  14. Colonization of Tomato Root by Antagonistic Bacterial Strains to Fusarium Wilt of Tomato

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    Arif Wibowo

    2005-12-01

    Full Text Available Fusarium wilt of tomato caused by Fusarium oxysporum f.sp. lycopersici (Fol is an important disease in tomato which cause a significant loss of yield in major growing regions of the world. This study examined the ability of bacterial strains antagonistic to F. oxysporum f.sp. lycopersici (H5, H22, H63, H71, Burkholderia cepacia strain 65 and 526 to colonize tomato seedlings and the effect of plant growth. The effect of bacterial population size and air temperature on the bacterial colonization and their spread along the root systems was also assessed.The results of this study showed that the bacterial population at 28°/23° C day/night temperature 14 days after planting was significantly greater than 23°/18° C for 4 of 6 strains tested. Although there was no significant effect of temperature on bacterial population observed in this study, the ability of the baacterial strains to colonize the rhizosphere was significantly different. Three strains (H5, B. cepacia strain 65 and 526 survived well in the rhizosphere and at 4 weeks after planting rhizosphere populations per gram fresh root were not significantly different from those recovered 2 weeks after planting. The largest population of the bacterial inoculants developed in the basal region of the roots and this differed between strains by log10 2.7 cfu/cm root. The bacterial populations in other parts of the root were also strain dependent. Strain H71, for example, was able to colonize the root segments at a high population level. However strain H63 was recovered only in small number in all root segments.

  15. Isolation and sequence analysis of the Pseudomonas syringae pv. tomato gene encoding a 2,3-diphosphoglycerate-independent phosphoglyceromutase.

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    Morris, V L; Jackson, D P; Grattan, M; Ainsworth, T; Cuppels, D A

    1995-01-01

    Pseudomonas syringae pv. tomato DC3481, a Tn5-induced mutant of the tomato pathogen DC3000, cannot grow and elicit disease symptoms on tomato seedlings. It also cannot grow on minimal medium containing malate, citrate, or succinate, three of the major organic acids found in tomatoes. We report here that this mutant also cannot use, as a sole carbon and/or energy source, a wide variety of hexoses and intermediates of hexose catabolism. Uptake studies have shown that DC3481 is not deficient in transport. A 3.8-kb EcoRI fragment of DC3000 DNA, which complements the Tn5 mutation, has been cloned and sequenced. The deduced amino acid sequences of two of the three open reading frames (ORFs) present on this fragment, ORF2 and ORF3, had no significant homology with sequences in the GenBank databases. However, the 510-amino-acid sequence of ORF1, the site of the Tn5 insertion, strongly resembled the deduced amino acid sequences of the Bacillus subtilis and Zea mays genes encoding 2,3-diphosphoglycerate (DPG)-independent phosphoglyceromutase (PGM) (52% identity and 72% similarity and 37% identity and 57% similarity, respectively). PGMs not requiring the cofactor DPG are usually found in plants and algae. Enzyme assays confirmed that P. syringae PGM activity required an intact ORF1. Not only is DC3481 the first PGM-deficient pseudomonad mutant to be described, but the P. syringae pgm gene is the first gram-negative bacterial gene identified that appears to code for a DPG-independent PGM. PGM activity appears essential for the growth and pathogenicity of P. syringae pv. tomato on its host plant. PMID:7896694

  16. Isolation and sequence analysis of the Pseudomonas syringae pv. tomato gene encoding a 2,3-diphosphoglycerate-independent phosphoglyceromutase.

    Science.gov (United States)

    Morris, V L; Jackson, D P; Grattan, M; Ainsworth, T; Cuppels, D A

    1995-04-01

    Pseudomonas syringae pv. tomato DC3481, a Tn5-induced mutant of the tomato pathogen DC3000, cannot grow and elicit disease symptoms on tomato seedlings. It also cannot grow on minimal medium containing malate, citrate, or succinate, three of the major organic acids found in tomatoes. We report here that this mutant also cannot use, as a sole carbon and/or energy source, a wide variety of hexoses and intermediates of hexose catabolism. Uptake studies have shown that DC3481 is not deficient in transport. A 3.8-kb EcoRI fragment of DC3000 DNA, which complements the Tn5 mutation, has been cloned and sequenced. The deduced amino acid sequences of two of the three open reading frames (ORFs) present on this fragment, ORF2 and ORF3, had no significant homology with sequences in the GenBank databases. However, the 510-amino-acid sequence of ORF1, the site of the Tn5 insertion, strongly resembled the deduced amino acid sequences of the Bacillus subtilis and Zea mays genes encoding 2,3-diphosphoglycerate (DPG)-independent phosphoglyceromutase (PGM) (52% identity and 72% similarity and 37% identity and 57% similarity, respectively). PGMs not requiring the cofactor DPG are usually found in plants and algae. Enzyme assays confirmed that P. syringae PGM activity required an intact ORF1. Not only is DC3481 the first PGM-deficient pseudomonad mutant to be described, but the P. syringae pgm gene is the first gram-negative bacterial gene identified that appears to code for a DPG-independent PGM. PGM activity appears essential for the growth and pathogenicity of P. syringae pv. tomato on its host plant.

  17. Effectiveness of composts and Trichoderma strains for control of Fusarium wilt of tomato

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    Yousra TAGHDI

    2015-09-01

    Full Text Available Fusarium wilt caused by Fusarium oxysporum f. sp. lycopersici (FOL is a major limiting disease in tomato production in Morocco. Commercial and locally produced Moroccan composts and peat were found to reduce Fusarium wilt in tomato plants. We explored the presence of Trichoderma strains in these materials, and in six soils sampled in the North West of Morocco, where a low incidence of Fusarium wilt had been previously observed. The most abundant Trichoderma-like fungus was selected from each soil, compost or peat sample. Twelve Trichoderma strains were isolated and identified molecularly. Trichoderma asperellum CT9 and Trichoderma virens ST11 showed the greatest overall antagonistic activity against FOL, Rhizoctonia solani, Botrytis cinerea and Pythium ultimum. The three strains evaluated in in planta tests, CT9, ST11 and T. virens ST10, reduced tomato Fusarium wilt, and strain ST11  also promoted growth of tomato plants.

  18. Pseudomonas syringae pv. Tomato DC3000 Type III secretion effector polymutants reveal an interplay between hopAD1 and AvrPtoB

    Science.gov (United States)

    The model pathogen Pseudomonas syringae pv. tomato DC3000 suppresses the two-tiered innate immune system of plants by injecting a complex repertoire of effector proteins into host cells via the type III secretion system. The model effector AvrPtoB has multiple domains and plant protein interactors i...

  19. Antibacterial effect of roselle extracts (Hibiscus sabadariffa), sodium hypochlorite and acetic acid against multidrug-resistant Salmonella strains isolated from tomatoes.

    Science.gov (United States)

    Gutiérrez-Alcántara, E J; Rangel-Vargas, E; Gómez-Aldapa, C A; Falfan-Cortes, R N; Rodríguez-Marín, M L; Godínez-Oviedo, A; Cortes-López, H; Castro-Rosas, J

    2016-02-01

    Antibiotic-resistant Salmonella strains were isolated from saladette and red round type tomatoes, and an analysis done of the antibacterial activity of roselle calyx extracts against any of the identified strains. One hundred saladette tomato samples and 100 red round tomato samples were collected from public markets. Each sample consisted of four whole tomatoes. Salmonella was isolated from the samples by conventional culture procedure. Susceptibility to 16 antibiotics was tested for the isolated Salmonella strains by standard test. The antibacterial effect of four roselle calyx extracts (water, methanol, acetone and ethyl acetate), sodium hypochlorite and acetic acid against antibiotic-resistant Salmonella isolates was evaluated on contaminated tomatoes. Twenty-four Salmonella strains were isolated from 12% of each tomato type. Identified Salmonella serotypes were Typhimurium and Typhi. All isolated strains exhibited resistance to at least three antibiotics and some to as many as 12. Over contaminated tomatoes, the roselle calyx extracts produced a greater reduction (2-2·6 log) in antibiotic-resistant Salmonella strain concentration than sodium hypochlorite and acetic acid. The presence of multidrug-resistant Salmonella in vegetables is a significant public health concern. Multidrug-resistant Salmonella strains were isolated from raw tomatoes purchased in public markets in Mexico and challenged with roselle Hibiscus sabdariffa calyx extracts, sodium hypochlorite and acetic acid. On tomatoes, the extracts caused a greater reduction in the concentration of antibiotic-resistant Salmonella strains than sodium hypochlorite and acetic acid. Roselle calyx extracts are a potentially useful addition to disinfection procedures of raw tomatoes in the field, processing plants, restaurants and homes. © 2015 The Society for Applied Microbiology.

  20. Association mapping of main tomato fruit sugars and organic acids

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    Jiantao Zhao

    2016-08-01

    Full Text Available Association mapping has been widely used to map the significant associated loci responsible for natural variation in complex traits and are valuable for crop improvement. Sugars and organic acids are the most important metabolites in tomato fruits. We used a collection of 174 tomato accessions composed of S. lycopersicum (123 accessions and S. lycopersicum var cerasiforme (51 accessions to detect significantly associated loci controlling the variation of main sugars and organic acids. The accessions were genotyped with 182 SSRs spreading over the tomato genome. Association mapping was conducted on the main sugars and organic acids detected by gas chromatography-mass spectrometer (GC-MS over two years using the mixed linear model (MLM. We detected a total of 58 significantly associated loci (P<0.001 for the 17 sugars and organic acids, including fructose, glucose, sucrose, citric acid, malic acid. These results not only co-localized with several reported QTLs, including fru9.1/PV, suc9.1/PV, ca2.1/HS, ca3.1/PV, ca4.1/PV and ca8.1/PV, but also provided a list of candidate significantly associated loci to be functionally validated. These significantly associated loci could be used for deciphering the genetic architecture of tomato fruit sugars and organic acids and for tomato quality breeding.

  1. A Biocontrol Strain of Bacillus subtilis WXCDD105 Used to Control Tomato Botrytis cinerea and Cladosporium fulvum Cooke and Promote the Growth of Seedlings

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    Hui Wang

    2018-05-01

    Full Text Available In this study, a strain named WXCDD105, which has strong antagonistic effects on Botrytis cinerea and Cladosporium fulvum Cooke, was screened out from the rhizosphere of healthy tomato plants. The tomato plants had inhibition diameter zones of 5.00 mm during the dual culture for four days. Based on the morphological and physiological characteristics, the 16S rDNA sequence, and the gyrB gene sequence analysis, the strain WXCDD105 was identified as Bacillus subtilis suBap. subtilis. The results of the mycelial growth test showed that the sterile filtrate of the strain WXCDD105 could significantly inhibit mycelial growth of Botrytis cinerea and Cladosporium fulvum Cooke. The inhibition rates were 95.28 and 94.44%, respectively. The potting experiment showed that the strain WXCDD105 made effective the control of tomato gray mold and tomato leaf mold. The control efficiencies were 74.70 and 72.07%. The antagonistic test results showed that the strain WXCDD105 had different degrees of inhibition on 10 kinds of plant pathogenic fungi and the average inhibition rates were more than 80%. We also found that the strain WXCDD105 stimulated both the seed germination and seedling growth of tomatoes. Using the fermentation liquid of WXCDD105 (108 cfu·mL−1 to treat the seeds, the germination rate and radicle length were increased. Under the treatment of the fermentation liquid of the strain WXCDD105 (106 cfu·mL−1, nearly all physiological indexes of tomato seedlings were significantly higher than that of the control groups. This could not only keep the nutritional quality of tomato fruits but also prevent them from rotting. This study provided us with an excellent strain for biological control of tomato gray mold, tomato leaf mold, and tomato growth promotion. This also laid the technical foundation for its application.

  2. Identification of Isolates that Cause a Leaf Spot Disease of Brassicas as Xanthomonas campestris pv. raphani and Pathogenic and Genetic Comparison with Related Pathovars.

    Science.gov (United States)

    Vicente, J G; Everett, B; Roberts, S J

    2006-07-01

    ABSTRACT Twenty-five Xanthomonas isolates, including some isolates received as either X. campestris pv. armoraciae or pv. raphani, caused discrete leaf spot symptoms when spray-inoculated onto at least one Brassica oleracea cultivar. Twelve of these isolates and four other Xanthomonas isolates were spray- and pin-inoculated onto 21 different plant species/cultivars including horseradish (Armoracia rusticana), radish (Raphanus sativus), and tomato (Lycopersicon esculentum). The remaining 13 leaf spot isolates were spray-inoculated onto a subset of 10 plant species/cultivars. The leaf spot isolates were very aggressive on several Brassica spp., radish, and tomato causing leaf spots and dark sunken lesions on the middle vein, petiole, and stem. Based on the differential reactions of several Brassica spp. and radish cultivars, the leaf spot isolates were divided into three races, with races 1 and 3 predominating. A differential series was established to determine the race-type of isolates and a gene-for-gene model based on the interaction of two avirulence genes in the pathogen races and two matching resistance genes in the differential hosts is proposed. Repetitive-DNA polymerase chain reaction-based fingerprinting was used to assess the genetic diversity of the leaf spot isolates and isolates of closely related Xanthomonas pathovars. Although there was variability within each race, the leaf spot isolates were clustered separately from the X. campestris pv. campestris isolates. We propose that X. campestris isolates that cause a nonvascular leaf spot disease on Brassica spp. should be identified as pv. raphani and not pv. armoraciae. Race-type strains and a neopathotype strain for X. campestris pv. raphani are proposed.

  3. Co-silencing of tomato S-adenosylhomocysteine hydrolase genes confers increased immunity against Pseudomonas syringae pv. tomato DC3000 and enhanced tolerance to drought stress

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    Li Xiao Hui

    2015-09-01

    Full Text Available S-adenosylhomocysteine hydrolase (SAHH, catalyzing the reversible hydrolysis of S-adenosylhomocysteine to adenosine and homocysteine, is a key enzyme that maintain the cellular methylation potential in all organisms. We report here the biological functions of tomato SlSAHHs in stress response. The tomato genome contains three SlSAHH genes that encode SlSAHH proteins with high level of sequence identity. qRT-PCR analysis revealed that SlSAHHs responded with distinct expression induction patterns to Pseudomonas syringae pv. tomato (Pst DC3000 and Botrytis cinerea as well as to defense signaling hormones such as salicylic acid, jasmonic acid and a precursor of ethylene. Virus-induced gene silencing-based knockdown of individual SlSAHH gene did not affect the growth performance and the response to Pst DC3000. However, co-silencing of three SlSAHH genes using a conserved sequence led to significant inhibition of vegetable growth. The SlSAHH-co-silenced plants displayed increased resistance to Pst DC3000 but did not alter the resistance to B. cinerea. Co-silencing of SlSAHHs resulted in constitutively activated defense responses including elevated SA level, upregulated expression of defense-related and PAMP-triggered immunity marker genes and increased callose deposition and H2O2 accumulation. Furthermore, the SlSAHH-co-silenced plants also exhibited enhanced drought stress tolerance although they had relatively small roots. These data demonstrate that, in addition to the functions in growth and development, SAHHs also play important roles in regulating biotic and abiotic stress responses in plants.

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

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    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

  5. Water Extract from Spent Mushroom Substrate of Hericium erinaceus Suppresses Bacterial Wilt Disease of Tomato

    Science.gov (United States)

    Kwak, A Min; Min, Kyeong Jin; Lee, Sang Yeop

    2015-01-01

    Culture filtrates of six different edible mushroom species were screened for antimicrobial activity against tomato wilt bacteria Ralstonia solanacearum B3. Hericium erinaceus, Lentinula edodes (Sanjo 701), Grifola frondosa, and Hypsizygus marmoreus showed antibacterial activity against the bacteria. Water, n-butanol, and ethyl acetate extracts of spent mushroom substrate (SMS) of H. erinaceus exhibited high antibacterial activity against different phytopathogenic bacteria: Pectobacterium carotovorum subsp. carotovorum, Agrobacterium tumefaciens, R. solanacearum, Xanthomonas oryzae pv. oryzae, X. campestris pv. campestris, X. axonopodis pv. vesicatoria, X. axonopodis pv. citiri, and X. axonopodis pv. glycine. Quantitative real-time PCR revealed that water extracts of SMS (WESMS) of H. erinaceus induced expressions of plant defense genes encoding β-1,3-glucanase (GluA) and pathogenesis-related protein-1a (PR-1a), associated with systemic acquired resistance. Furthermore, WESMS also suppressed tomato wilt disease caused by R. solanacearum by 85% in seedlings and promoted growth (height, leaf number, and fresh weight of the root and shoot) of tomato plants. These findings suggest the WESMS of H. erinaceus has the potential to suppress bacterial wilt disease of tomato through multiple effects including antibacterial activity, plant growth promotion, and defense gene induction. PMID:26539048

  6. Chemical characterization of Xanthan biopolymers synthesized by Xanthomonas campestris pv pruni strains

    International Nuclear Information System (INIS)

    Moreira, Angelita da S.; Vendruscolo, Claire T.; Furlan, Ligia; Galland, Griselda

    2001-01-01

    In this work we describe the characterisation of Xanthan biopolymers synthesized by two Xanthomonas campestris pv pruni strains, in aerobic fermentation. By chromatography on TLC we could notice the presence of Mannose monomer in higher proportion in the 82 strain with relation to the another ones. The viscosity results showed the temperature dependence. The 06 and 82 strains had their viscosity increased whereas for the 87 strain we could observe a reduction with temperature increasing. The 13 C NMR spectrum of 87 strain showed the characteristic signals at approximately 92.8, 70.4 and 61.4 ppm, attributed to C1, C4 and C6 from glucose monomer, with higher intensity. (author)

  7. Characterization of Alternaria strains from Argentinean blueberry, tomato, walnut and wheat

    DEFF Research Database (Denmark)

    Andersen, Birgitte; Nielsen, Kristian Fog; Fernández Pinto, Virginia

    2015-01-01

    of the chemical potential. Four strains belonged to the Alternaria infectoria sp.-grp., 6 to the Alternaria arborescens sp.-grp., 6 showed a sporulation pattern similar to that of “M” according to Simmons, 1 to that of Alternaria vaccinii, and the remaining 70 constituted a diverse group belonging...... sporulation pattern “M” were only isolated from tomatoes. Otherwise, no clear association between substrate and identity could be found. The analyses in the study show that at least 75% of the Argentinean strains are able to produce potential mycotoxins....

  8. Chemical characterization of Xanthan biopolymers synthesized by Xanthomonas campestris pv pruni strains; Caracterizacao quimica de biopolimeros sintetizados por Xanthomonas campestris pv pruni

    Energy Technology Data Exchange (ETDEWEB)

    Moreira, Angelita da S.; Vendruscolo, Claire T.; Furlan, Ligia [Universidade Federal de Pelotas, RS (Brazil). Centro de Biotecnologia]. E-mail: angelita@ufpel.tche.br; claire@ufpel.tche.br; ligia@ufpel.tche.br; Galland, Griselda [Rio Grande do Sul Univ., Porto Alegre, RS (Brazil). Inst. de Qumica

    2001-07-01

    In this work we describe the characterisation of Xanthan biopolymers synthesized by two Xanthomonas campestris pv pruni strains, in aerobic fermentation. By chromatography on TLC we could notice the presence of Mannose monomer in higher proportion in the 82 strain with relation to the another ones. The viscosity results showed the temperature dependence. The 06 and 82 strains had their viscosity increased whereas for the 87 strain we could observe a reduction with temperature increasing. The {sup 13}C NMR spectrum of 87 strain showed the characteristic signals at approximately 92.8, 70.4 and 61.4 ppm, attributed to C1, C4 and C6 from glucose monomer, with higher intensity. (author)

  9. A Novel Reporter Rat Strain That Conditionally Expresses the Bright Red Fluorescent Protein tdTomato.

    Directory of Open Access Journals (Sweden)

    Hiroyuki Igarashi

    Full Text Available Despite the strength of the Cre/loxP recombination system in animal models, its application in rats trails that in mice because of the lack of relevant reporter strains. Here, we generated a floxed STOP tdTomato rat that conditionally expresses a red fluorescent protein variant (tdTomato in the presence of exogenous Cre recombinase. The tdTomato signal vividly visualizes neurons including their projection fibers and spines without any histological enhancement. In addition, a transgenic rat line (FLAME that ubiquitously expresses tdTomato was successfully established by injecting intracytoplasmic Cre mRNA into fertilized ova. Our rat reporter system will facilitate connectome studies as well as the visualization of the fine structures of genetically identified cells for long periods both in vivo and ex vivo. Furthermore, FLAME is an ideal model for organ transplantation research owing to improved traceability of cells/tissues.

  10. Virus-induced Gene Silencing-based Functional Analyses Revealed the Involvement of Several Putative Trehalose-6-Phosphate Synthase/Phosphatase Genes in Disease Resistance against Botrytis cinerea and Pseudomonas syringae pv. tomato DC3000 in Tomato

    Directory of Open Access Journals (Sweden)

    Huijuan Zhang

    2016-08-01

    Full Text Available Trehalose and its metabolism have been demonstrated to play important roles in control of plant growth, development and stress responses. However, direct genetic evidence supporting the functions of trehalose and its metabolism in defense response against pathogens is lacking. In the present study, genome-wide characterization of putative trehalose-related genes identified 11 SlTPSs for trehalose-6-phosphate synthase, 8 SlTPPs for trehalose-6-phosphate phosphatase and one SlTRE1 for trehalase in tomato genome. Nine SlTPSs, 4 SlTPPs and SlTRE1 were selected for functional analyses to explore their involvement in tomato disease resistance. Some selected SlTPSs, SlTPPs and SlTRE1 responded with distinct expression induction patterns to Botrytis cinerea and Pseudomonas syringae pv. tomato (Pst DC3000 as well as to defense signaling hormones (e.g. salicylic acid, jasmonic acid and a precursor of ethylene. Virus-induced gene silencing-mediated silencing of SlTPS3, SlTPS4 or SlTPS7 led to deregulation of ROS accumulation and attenuated the expression of defense-related genes upon pathogen infection and thus deteriorated the resistance against B. cinerea or Pst DC3000. By contrast, silencing of SlTPS5 or SlTPP2 led to an increased expression of the defense-related genes upon pathogen infection and conferred an increased resistance against Pst DC3000. Silencing of SlTPS3, SlTPS4, SlTPS5, SlTPS7 or SlTPP2 affected trehalose level in tomato plants with or without infection of B. cinerea or Pst DC3000. These results demonstrate that SlTPS3, SlTPS4, SlTPS5, SlTPS7 and SlTPP2 play roles in resistance against B. cinerea and Pst DC3000, implying the importance of trehalose and tis metabolism in regulation of defense response against pathogens in tomato.

  11. Biocontrol of Fusarium Crown and Root Rot and Promotion of Growth of Tomato by Paenibacillus Strains Isolated from Soil

    Science.gov (United States)

    Xu, Sheng Jun

    2014-01-01

    In this study, bacterial strains were isolated from soils from 30 locations of Samcheok, Gangwon province. Of the isolated strains, seven showed potential plant growth promoting and antagonistic activities. Based on cultural and morphological characterization, and 16S rRNA gene sequencing, these strains were identified as Paenibacillus species. All seven strains produced ammonia, cellulase, hydrocyanic acid, indole-3-acetic acid, protease, phosphatase, and siderophores. They also inhibited the mycelial growth of Fusarium oxysporum f. sp. radicis-lycopersici in vitro. The seven Paenibacillus strains enhanced a range of growth parameters in tomato plants under greenhouse conditions, in comparison with non-inoculated control plants. Notably, treatment of tomato plants with one identified strain, P. polymyxa SC09-21, resulted in 80.0% suppression of fusarium crown and root rot under greenhouse conditions. The plant growth promoting and antifungal activity of P. polymyxa SC09-21 identified in this study highlight its potential suitability as a bioinoculant. PMID:25071385

  12. Role of soil, crop debris, and a plant pathogen in Salmonella enterica contamination of tomato plants.

    Directory of Open Access Journals (Sweden)

    Jeri D Barak

    Full Text Available BACKGROUND: In the U.S., tomatoes have become the most implicated vehicle for produce-associated Salmonellosis with 12 outbreaks since 1998. Although unconfirmed, trace backs suggest pre-harvest contamination with Salmonella enterica. Routes of tomato crop contamination by S. enterica in the absence of direct artificial inoculation have not been investigated. METHODOLOGY/PRINCIPAL FINDINGS: This work examined the role of contaminated soil, the potential for crop debris to act as inoculum from one crop to the next, and any interaction between the seedbourne plant pathogen Xanthomonas campestris pv. vesicatoria and S. enterica on tomato plants. Our results show S. enterica can survive for up to six weeks in fallow soil with the ability to contaminate tomato plants. We found S. enterica can contaminate a subsequent crop via crop debris; however a fallow period between crop incorporation and subsequent seeding can affect contamination patterns. Throughout these studies, populations of S. enterica declined over time and there was no bacterial growth in either the phyllosphere or rhizoplane. The presence of X. campestris pv. vesicatoria on co-colonized tomato plants had no effect on the incidence of S. enterica tomato phyllosphere contamination. However, growth of S. enterica in the tomato phyllosphere occurred on co-colonized plants in the absence of plant disease. CONCLUSIONS/SIGNIFICANCE: S. enterica contaminated soil can lead to contamination of the tomato phyllosphere. A six week lag period between soil contamination and tomato seeding did not deter subsequent crop contamination. In the absence of plant disease, presence of the bacterial plant pathogen, X. campestris pv. vesicatoria was beneficial to S. enterica allowing multiplication of the human pathogen population. Any event leading to soil contamination with S. enterica could pose a public health risk with subsequent tomato production, especially in areas prone to bacterial spot disease.

  13. Genetic diversity and distribution of a distinct strain of Chili leaf curl virus and associated betasatellite infecting tomato and pepper in Oman.

    Science.gov (United States)

    Khan, Akhtar J; Akhtar, Sohail; Al-Zaidi, Amal M; Singh, Achuit K; Briddon, Rob W

    2013-10-01

    Tomato and pepper are widely grown in Oman for local consumption. A countrywide survey was conducted during 2010-2011 to collect samples and assess the diversity of begomoviruses associated with leaf curl disease of tomato and pepper. A virus previously only identified on the Indian subcontinent, chili leaf curl virus (ChLCV), was found associated with tomato and pepper diseases in all vegetable grown areas of Oman. Some of the infected plant samples were also found to contain a betasatellite. A total of 19 potentially full-length begomovirus and eight betasatellite clones were sequenced. The begomovirus clones showed >96% nucleotide sequence identity, showing them to represent a single species. Comparisons to sequences available in the databases showed the highest levels of nucleotide sequence identity (88.0-91.1%) to isolates of the "Pakistan" strain of ChLCV (ChLCV-PK), indicating the virus from Oman to be a distinct strain, for which the name Oman strain (ChLCV-OM) is proposed. An analysis for recombination showed ChLCV-OM likely to have originated by recombination between ChLCV-PK (the major parent), pepper leaf curl Lahore virus and a third strain of ChLCV. The betasatellite sequences obtained were shown to have high levels of identity to isolates of tomato leaf curl betasatellite (ToLCB) previous shown to be present in Oman. For the disease in tomato Koch's postulates were satisfied by Agrobacterium-mediated inoculation of virus and betasatellites clones. This showed the symptoms induced by the virus in the presence of the betasatellite to be enhanced, although viral DNA levels were not affected. ChLCV-OM is the fourth begomovirus identified in tomato in Oman and the first in Capsicum. The significance of these findings is discussed. Copyright © 2013 Elsevier B.V. All rights reserved.

  14. Transcriptional Dynamics Driving MAMP-Triggered Immunity and Pathogen Effector-Mediated Immunosuppression in Arabidopsis Leaves Following Infection with Pseudomonas syringae pv tomato DC3000.

    Science.gov (United States)

    Lewis, Laura A; Polanski, Krzysztof; de Torres-Zabala, Marta; Jayaraman, Siddharth; Bowden, Laura; Moore, Jonathan; Penfold, Christopher A; Jenkins, Dafyd J; Hill, Claire; Baxter, Laura; Kulasekaran, Satish; Truman, William; Littlejohn, George; Prusinska, Justyna; Mead, Andrew; Steinbrenner, Jens; Hickman, Richard; Rand, David; Wild, David L; Ott, Sascha; Buchanan-Wollaston, Vicky; Smirnoff, Nick; Beynon, Jim; Denby, Katherine; Grant, Murray

    2015-11-01

    Transcriptional reprogramming is integral to effective plant defense. Pathogen effectors act transcriptionally and posttranscriptionally to suppress defense responses. A major challenge to understanding disease and defense responses is discriminating between transcriptional reprogramming associated with microbial-associated molecular pattern (MAMP)-triggered immunity (MTI) and that orchestrated by effectors. A high-resolution time course of genome-wide expression changes following challenge with Pseudomonas syringae pv tomato DC3000 and the nonpathogenic mutant strain DC3000hrpA- allowed us to establish causal links between the activities of pathogen effectors and suppression of MTI and infer with high confidence a range of processes specifically targeted by effectors. Analysis of this information-rich data set with a range of computational tools provided insights into the earliest transcriptional events triggered by effector delivery, regulatory mechanisms recruited, and biological processes targeted. We show that the majority of genes contributing to disease or defense are induced within 6 h postinfection, significantly before pathogen multiplication. Suppression of chloroplast-associated genes is a rapid MAMP-triggered defense response, and suppression of genes involved in chromatin assembly and induction of ubiquitin-related genes coincide with pathogen-induced abscisic acid accumulation. Specific combinations of promoter motifs are engaged in fine-tuning the MTI response and active transcriptional suppression at specific promoter configurations by P. syringae. © 2015 American Society of Plant Biologists. All rights reserved.

  15. Characterisation of the mgo operon in Pseudomonas syringae pv. syringae UMAF0158 that is required for mangotoxin production

    Science.gov (United States)

    2012-01-01

    Background Mangotoxin is an antimetabolite toxin that is produced by strains of Pseudomonas syringae pv. syringae; mangotoxin-producing strains are primarily isolated from mango tissues with symptoms of bacterial apical necrosis. The toxin is an oligopeptide that inhibits ornithine N-acetyl transferase (OAT), a key enzyme in the biosynthetic pathway of the essential amino acids ornithine and arginine. The involvement of a putative nonribosomal peptide synthetase gene (mgoA) in mangotoxin production and virulence has been reported. Results In the present study, we performed a RT-PCR analysis, insertional inactivation mutagenesis, a promoter expression analysis and terminator localisation to study the gene cluster containing the mgoA gene. Additionally, we evaluated the importance of mgoC, mgoA and mgoD in mangotoxin production. A sequence analysis revealed an operon-like organisation. A promoter sequence was located upstream of the mgoB gene and was found to drive lacZ transcription. Two terminators were located downstream of the mgoD gene. RT-PCR experiments indicated that the four genes (mgoBCAD) constitute a transcriptional unit. This operon is similar in genetic organisation to those in the three other P. syringae pathovars for which complete genomes are available (P. syringae pv. syringae B728a, P. syringae pv. tomato DC3000 and P. syringae pv. phaseolicola 1448A). Interestingly, none of these three reference strains is capable of producing mangotoxin. Additionally, extract complementation resulted in a recovery of mangotoxin production when the defective mutant was complemented with wild-type extracts. Conclusions The results of this study confirm that mgoB, mgoC, mgoA and mgoD function as a transcriptional unit and operon. While this operon is composed of four genes, only the last three are directly involved in mangotoxin production. PMID:22251433

  16. A resistance locus in the American heirloom rice variety Carolina Gold Select is triggered by TAL effectors with diverse predicted targets and is effective against African strains of Xanthomonas oryzae pv. oryzicola.

    Science.gov (United States)

    Triplett, Lindsay R; Cohen, Stephen P; Heffelfinger, Christopher; Schmidt, Clarice L; Huerta, Alejandra I; Tekete, Cheick; Verdier, Valerie; Bogdanove, Adam J; Leach, Jan E

    2016-09-01

    The rice pathogens Xanthomonas oryzae pathovar (pv.) oryzae and pv. oryzicola produce numerous transcription activator-like (TAL) effectors that increase bacterial virulence by activating expression of host susceptibility genes. Rice resistance mechanisms against TAL effectors include polymorphisms that prevent effector binding to susceptibility gene promoters, or that allow effector activation of resistance genes. This study identifies, in the heirloom variety Carolina Gold Select, a third mechanism of rice resistance involving TAL effectors. This resistance manifests through strong suppression of disease development in response to diverse TAL effectors from both X. oryzae pathovars. The resistance can be triggered by an effector with only 3.5 central repeats, is independent of the composition of the repeat variable di-residues that determine TAL effector binding specificity, and is independent of the transcriptional activation domain. We determined that the resistance is conferred by a single dominant locus, designated Xo1, that maps to a 1.09 Mbp fragment on chromosome 4. The Xo1 interval also confers complete resistance to the strains in the African clade of X. oryzae pv. oryzicola, representing the first dominant resistance locus against bacterial leaf streak in rice. The strong phenotypic similarity between the TAL effector-triggered resistance conferred by Xo1 and that conferred by the tomato resistance gene Bs4 suggests that monocots and dicots share an ancient or convergently evolved mechanism to recognize analogous TAL effector epitopes. © 2016 The Authors The Plant Journal © 2016 John Wiley & Sons Ltd.

  17. Complete genome sequence of two tomato-infecting begomoviruses in Venezuela: evidence of a putative novel species and a novel recombinant strain.

    Science.gov (United States)

    Romay, Gustavo; Chirinos, Dorys T; Geraud-Pouey, Francis; Gillis, Annika; Mahillon, Jacques; Bragard, Claude

    2018-02-01

    At least six begomovirus species have been reported infecting tomato in Venezuela. In this study the complete genomes of two tomato-infecting begomovirus isolates (referred to as Trujillo-427 and Zulia-1084) were cloned and sequenced. Both isolates showed the typical genome organization of New World bipartite begomoviruses, with DNA-A genomic components displaying 88.8% and 90.3% similarity with established begomoviruses, for isolates Trujillo-427 and Zulia-1084, respectively. In accordance to the guidelines for begomovirus species demarcation, the Trujillo-427 isolate represents a putative new species and the name "Tomato wrinkled mosaic virus" is proposed. Meanwhile, Zulia-1084 represents a putative new strain classifiable within species Tomato chlorotic leaf distortion virus, for which a recombinant origin is suggested.

  18. Emergence of a resistance breaking TSWV strain in tomato in California

    Science.gov (United States)

    Tomato spotted wilt virus (TSWV) is a highly destructive pathogen of tomato in the central valley of California. During the 2016 tomato growing season, unusually early and severe symptoms of TSWV occurred in fields of TSWV-resistant fresh market tomato cultivars. Disease incidences of 50-80% were ob...

  19. Multilocus Sequence Typing Reveals Relevant Genetic Variation and Different Evolutionary Dynamics among Strains of Xanthomonas arboricola pv. juglandis

    Directory of Open Access Journals (Sweden)

    Marco Scortichini

    2010-11-01

    Full Text Available Forty-five Xanthomonas arboricola pv. juglandis (Xaj strains originating from Juglans regia cultivation in different countries were molecularly typed by means of MultiLocus Sequence Typing (MLST, using acnB, gapA, gyrB and rpoD gene fragments. A total of 2.5 kilobases was used to infer the phylogenetic relationship among the strains and possible recombination events. Haplotype diversity, linkage disequilibrium analysis, selection tests, gene flow estimates and codon adaptation index were also assessed. The dendrograms built by maximum likelihood with concatenated nucleotide and amino acid sequences revealed two major and two minor phylotypes. The same haplotype was found in strains originating from different continents, and different haplotypes were found in strains isolated in the same year from the same location. A recombination breakpoint was detected within the rpoD gene fragment. At the pathovar level, the Xaj populations studied here are clonal and under neutral selection. However, four Xaj strains isolated from walnut fruits with apical necrosis are under diversifying selection, suggesting a possible new adaptation. Gene flow estimates do not support the hypothesis of geographic isolation of the strains, even though the genetic diversity between the strains increases as the geographic distance between them increases. A triplet deletion, causing the absence of valine, was found in the rpoD fragment of all 45 Xaj strains when compared with X. axonopodis pv. citri strain 306. The codon adaptation index was high in all four genes studied, indicating a relevant metabolic activity.

  20. Potencialidade de um actinomiceto de rizosfera de tomateiro como agente de biocontrole de doenças Potenciality of an actinomycete from tomato rhizosphere as a biocontrol agent for tomato diseases

    Directory of Open Access Journals (Sweden)

    Renato Carrer Filho

    2009-09-01

    Full Text Available Um actinomiceto (Streptomyces setonii, isolado 'UFV-RD1', obtido de rizosfera de planta sadia de tomateiro, foi selecionado dentre outros 117, como promissor agente de biocontrole de enfermidades da cultura. Em testes de antagonismo in vitro contra patógenos do tomateiro, o isolado 'UFV-RD1' foi incapaz de inibir o crescimento de bactérias (Pseudomonas syringae pv. tomato, Ralstonia solanacearum, Pectobacterium carotovorum subsp. carotovorum, Xanthomonas campestris pv. vesicatoria mas inibiu a germinação de conídios de alguns fungos (Alternaria solani, Phytophthora infestans, Corynespora cassiicola, Stemphylium solani. Em ensaios de biocontrole experimental in vivo, em casa de vegetação, o actinomiceto foi efetivo em reduzir a severidade de sintomas no caso de patógenos fúngicos e bacterianos testados como desafiantes. A campo, quando A. solani e P. infestans ocorreram naturalmente, as plantas originárias de sementes microbiolizadas com propágulos da estirpe 'UFV-RD1' exibiram sintomas menos severos que as plantas controle para o caso da pinta preta. O agente de biocontrole é promissor para futuros protocolos de manejo integrado, como forma de reduzir a quantidade de defensivos utilizados.An actinomycete (Streptomyces setonii, isolate 'UFV-RD1', isolated from the rhizosphere of a healthy tomato plant was selected out of 117 as a promising biocontrol agent for tomato diseases. In in vitro antagonism tests against tomato pathogens, the isolate 'UFV-RD1' was unable to inhibit growth of bacterial pathogens (Pseudomonas syringae pv. tomato, Ralstonia solanacearum, Pectobacterium carotovorum subsp. carotovorum, Xanthomonas campestris pv. vesicatoria but inhibited conidium germination of fungi (Alternaria solani, Phytophthora infestans, Corynespora cassiicola, Stemphylium solani. Experimental biocontrol assays in a greenhouse indicated that the actinomycete was effective for reducing symptom severity in the case of bacteria and fungi tested

  1. Systemic resistance and lipoxygenase-related defence response induced in tomato by Pseudomonas putida strain BTP1

    Directory of Open Access Journals (Sweden)

    Dommes Jacques

    2008-11-01

    Full Text Available Abstract Background Previous studies showed the ability of Pseudomonas putida strain BTP1 to promote induced systemic resistance (ISR in different host plants. Since ISR is long-lasting and not conducive for development of resistance of the targeted pathogen, this phenomenon can take part of disease control strategies. However, in spite of the numerous examples of ISR induced by PGPR in plants, only a few biochemical studies have associated the protective effect with specific host metabolic changes. Results In this study, we showed the protective effect of this bacterium in tomato against Botrytis cinerea. Following treatment by P. putida BTP1, analyses of acid-hydrolyzed leaf extracts showed an accumulation of antifungal material after pathogen infection. The fungitoxic compounds thus mainly accumulate as conjugates from which active aglycones may be liberated through the activity of hydrolytic enzymes. These results suggest that strain BTP1 can elicit systemic phytoalexin accumulation in tomato as one defence mechanism. On another hand, we have shown that key enzymes of the lipoxygenase pathway are stimulated in plants treated with the bacteria as compared with control plants. Interestingly, this stimulation is observed only after pathogen challenge in agreement with the priming concept almost invariably associated with the ISR phenomenon. Conclusion Through the demonstration of phytoalexin accumulation and LOX pathway stimulation in tomato, this work provides new insights into the diversity of defence mechanisms that are inducible by non-pathogenic bacteria in the context of ISR.

  2. Expression of the Bs2 pepper gene confers resistance to bacterial spot disease in tomato.

    Science.gov (United States)

    Tai, T H; Dahlbeck, D; Clark, E T; Gajiwala, P; Pasion, R; Whalen, M C; Stall, R E; Staskawicz, B J

    1999-11-23

    The Bs2 resistance gene of pepper specifically recognizes and confers resistance to strains of Xanthomonas campestris pv. vesicatoria that contain the corresponding bacterial avirulence gene, avrBs2. The involvement of avrBs2 in pathogen fitness and its prevalence in many X. campestris pathovars suggests that the Bs2 gene may be durable in the field and provide resistance when introduced into other plant species. Employing a positional cloning strategy, the Bs2 locus was isolated and the gene was identified by coexpression with avrBs2 in an Agrobacterium-mediated transient assay. A single candidate gene, predicted to encode motifs characteristic of the nucleotide binding site-leucine-rich repeat class of resistance genes, was identified. This gene specifically controlled the hypersensitive response when transiently expressed in susceptible pepper and tomato lines and in a nonhost species, Nicotiana benthamiana, and was designated as Bs2. Functional expression of Bs2 in stable transgenic tomatoes supports its use as a source of resistance in other Solanaceous plant species.

  3. Comparative genomic analysis of two-component regulatory proteins in Pseudomonas syringae

    DEFF Research Database (Denmark)

    Lavin, J.L.; Kiil, Kristoffer; Resano, O.

    2007-01-01

    Background: Pseudomonas syringae is a widespread bacterial plant pathogen, and strains of P. syringae may be assigned to different pathovars based on host specificity among different plant species. The genomes of P. syringae pv. syringae (Psy) B728a, pv. tomato (Pto) DC3000 and pv. phaseolicola...

  4. Strains of Peru tomato virus infecting cocona (Solanum sessiliflorum), tomato and pepper in Peru with reference to genome evolution in genus Potyvirus.

    Science.gov (United States)

    Melgarejo, T A; Alminaite, A; Fribourg, C; Spetz, C; Valkonen, J P T

    2004-10-01

    Two isolates (SL1 and SL6) of Peru tomato virus (PTV, genus Potyvirus) were obtained from cocona plants (Solanum sessiliflorum) growing in Tingo María, the jungle of the Amazon basin in Peru. One PTV isolate (TM) was isolated from a tomato plant (Lycopersicon esculentum) growing in Huaral at the Peruvian coast. The three PTV isolates were readily transmissible by Myzus persicae. Isolate SL1, but not SL6, caused chlorotic lesions in inoculated leaves of Chenopodium amaranticolor and C. quinoa. Isolate TM differed from SL1 and SL6 in causing more severe mosaic symptoms in tomato, and vein necrosis in the leaves of cocona. Pepper cv. Avelar (Capsicum annuum) showed resistance to the PTV isolates SL1 and SL6 but not TM. The 5'- and 3'-proximal sequences of the three PTV isolates were cloned, sequenced and compared to the corresponding sequences of four PTV isolates from pepper, the only host from which PTV isolates have been previously characterised at the molecular level. Phylogenetic analyses on the P1 protein and coat protein amino acid sequences indicated, in accordance with the phenotypic data from indicator hosts, that the PTV isolates from cocona represented a distinguishable strain. In contrast, the PTV isolates from tomato and pepper were not grouped according to the host. Inclusion of the sequence data from the three PTV isolates of this study in a phylogenetic analysis with other PTV isolates and other potyviruses strengthen the membership of PTV in the so-called "PVY subgroup" of Potyvirus. This subgroup of closely related potyvirus species was also distinguishable from other potyviruses by their more uniform sizes of the protein-encoding regions within the polyprotein.

  5. Cell wall-bound invertase limits sucrose export and is involved in symptom development and inhibition of photosynthesis during compatible interaction between tomato and Xanthomonas campestris pv vesicatoria.

    Science.gov (United States)

    Kocal, Nurcan; Sonnewald, Uwe; Sonnewald, Sophia

    2008-11-01

    Cell wall-bound invertase (cw-Inv) plays an important role in carbohydrate partitioning and regulation of sink-source interaction. There is increasing evidence that pathogens interfere with sink-source interaction, and induction of cw-Inv activity has frequently been shown in response to pathogen infection. To investigate the role of cw-Inv, transgenic tomato (Solanum lycopersicum) plants silenced for the major leaf cw-Inv isoforms were generated and analyzed during normal growth and during the compatible interaction with Xanthomonas campestris pv vesicatoria. Under normal growth conditions, activities of sucrolytic enzymes as well as photosynthesis and respiration were unaltered in the transgenic plants compared with wild-type plants. However, starch levels of source leaves were strongly reduced, which was most likely caused by an enhanced sucrose exudation rate. Following X. campestris pv vesicatoria infection, cw-Inv-silenced plants showed an increased sucrose to hexose ratio in the apoplast of leaves. Symptom development, inhibition of photosynthesis, and expression of photosynthetic genes were clearly delayed in transgenic plants compared with wild-type plants. In addition, induction of senescence-associated and pathogenesis-related genes observed in infected wild-type plants was abolished in cw-Inv-silenced tomato lines. These changes were not associated with decreased bacterial growth. In conclusion, cw-Inv restricts carbon export from source leaves and regulates the sucrose to hexose ratio in the apoplast. Furthermore, an increased apoplastic hexose to sucrose ratio can be linked to inhibition of photosynthesis and induction of pathogenesis-related gene expression but does not significantly influence bacterial growth. Indirectly, bacteria may benefit from low invertase activity, since the longevity of host cells is raised and basal defense might be dampened.

  6. Modular Study of the Type III Effector Repertoire in Pseudomonas syringae pv. tomato DC3000 Reveals a Matrix of Effector Interplay in Pathogenesis

    Directory of Open Access Journals (Sweden)

    Hai-Lei Wei

    2018-05-01

    Full Text Available Summary: The bacterial pathogen Pseudomonas syringae pv. tomato DC3000 suppresses the two-tiered innate immune system of Nicotiana benthamiana and other plants by injecting a complex repertoire of type III secretion effector (T3E proteins. Effectorless polymutant DC3000D36E was used with a modularized system for native delivery of the 29 DC3000 T3Es singly and in pairs. Assays of the performance of this T3E library in N. benthamiana leaves revealed a matrix of T3E interplay, with six T3Es eliciting death and eight others variously suppressing the death activity of the six. The T3E library was also interrogated for effects on DC3000D36E elicitation of a reactive oxygen species burst, for growth in planta, and for T3Es that reversed these effects. Pseudomonas fluorescens and Agrobacterium tumefaciens heterologous delivery systems yielded notably different sets of death-T3Es. The DC3000D36E T3E library system highlights the importance of 13 T3Es and their interplay in interactions with N. benthamiana. : Wei et al. used a Pseudomonas syringae strain lacking all known type III effectors with a modularized library expressing the 29 active effectors in the strain’s native repertoire, individually and in pairs, to comprehensively determine effector actions and interplay in inducing and suppressing responses associated with plant pathogenesis and immunity. Keywords: effector-triggered-immunity, pattern-triggered-immunity, Hop proteins, plant immunity, mini-Tn7

  7. Differential secretome analysis of Pseudomonas syringae pv tomato using gel-free MS proteomics

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    Jörg eSchumacher

    2014-07-01

    Full Text Available The plant pathogen Pseudomonas syringae pv. tomato (DC3000 causes virulence by delivering effector proteins into host plant cells through its type three secretion system (T3SS. In response to the plant environment DC3000 expresses hypersensitive response and pathogenicity genes (hrp. Pathogenesis depends on the ability of the pathogen to manipulate the plant metabolism and to inhibit plant immunity, which depends to a large degree on the plant’s capacity to recognise both pathogen and microbial determinants (PAMP/MAMP-triggered immunity. We have developed and employed MS-based shotgun and targeted proteomics to (i elucidate the extracellular and secretome composition of DC3000 and (ii evaluate temporal features of the assembly of the T3SS and the secretion process together with its dependence of pH. The proteomic screen, under hrp inducing in vitro conditions, of extracellular and cytoplasmatic fractions indicated the segregated presence of not only T3SS implicated proteins such as HopK1, HrpK1, HrpA1 and Avrpto1, but also of proteins not usually associated with the T3SS or with pathogenicity. Using multiple reaction monitoring MS (MRM-MS to quantify HrpA1 and Avrpto1, we found that HrpA1 is rapidly expressed, at a strict pH-dependent rate and is post-translationally processed extracellularly. These features appear to not interfere with rapid Avrpto1 expression and secretion but may suggest some temporal post-translational regulatory mechanism of the T3SS assembly. The high specificity and sensitivity of the MRM-MS approach should provide a powerful tool to measure secretion and translocation in infected tissues.

  8. Genomic survey of pathogenicity determinants and VNTR markers in the cassava bacterial pathogen Xanthomonas axonopodis pv. Manihotis strain CIO151.

    Science.gov (United States)

    Arrieta-Ortiz, Mario L; Rodríguez-R, Luis M; Pérez-Quintero, Álvaro L; Poulin, Lucie; Díaz, Ana C; Arias Rojas, Nathalia; Trujillo, Cesar; Restrepo Benavides, Mariana; Bart, Rebecca; Boch, Jens; Boureau, Tristan; Darrasse, Armelle; David, Perrine; Dugé de Bernonville, Thomas; Fontanilla, Paula; Gagnevin, Lionel; Guérin, Fabien; Jacques, Marie-Agnès; Lauber, Emmanuelle; Lefeuvre, Pierre; Medina, Cesar; Medina, Edgar; Montenegro, Nathaly; Muñoz Bodnar, Alejandra; Noël, Laurent D; Ortiz Quiñones, Juan F; Osorio, Daniela; Pardo, Carolina; Patil, Prabhu B; Poussier, Stéphane; Pruvost, Olivier; Robène-Soustrade, Isabelle; Ryan, Robert P; Tabima, Javier; Urrego Morales, Oscar G; Vernière, Christian; Carrere, Sébastien; Verdier, Valérie; Szurek, Boris; Restrepo, Silvia; López, Camilo; Koebnik, Ralf; Bernal, Adriana

    2013-01-01

    Xanthomonas axonopodis pv. manihotis (Xam) is the causal agent of bacterial blight of cassava, which is among the main components of human diet in Africa and South America. Current information about the molecular pathogenicity factors involved in the infection process of this organism is limited. Previous studies in other bacteria in this genus suggest that advanced draft genome sequences are valuable resources for molecular studies on their interaction with plants and could provide valuable tools for diagnostics and detection. Here we have generated the first manually annotated high-quality draft genome sequence of Xam strain CIO151. Its genomic structure is similar to that of other xanthomonads, especially Xanthomonas euvesicatoria and Xanthomonas citri pv. citri species. Several putative pathogenicity factors were identified, including type III effectors, cell wall-degrading enzymes and clusters encoding protein secretion systems. Specific characteristics in this genome include changes in the xanthomonadin cluster that could explain the lack of typical yellow color in all strains of this pathovar and the presence of 50 regions in the genome with atypical nucleotide composition. The genome sequence was used to predict and evaluate 22 variable number of tandem repeat (VNTR) loci that were subsequently demonstrated as polymorphic in representative Xam strains. Our results demonstrate that Xanthomonas axonopodis pv. manihotis strain CIO151 possesses ten clusters of pathogenicity factors conserved within the genus Xanthomonas. We report 126 genes that are potentially unique to Xam, as well as potential horizontal transfer events in the history of the genome. The relation of these regions with virulence and pathogenicity could explain several aspects of the biology of this pathogen, including its ability to colonize both vascular and non-vascular tissues of cassava plants. A set of 16 robust, polymorphic VNTR loci will be useful to develop a multi-locus VNTR analysis

  9. Response of tobacco to the Pseudomonas syringae pv. Tomato DC3000 is mainly dependent on salicylic acid signaling pathway.

    Science.gov (United States)

    Liu, Yang; Wang, Li; Cai, Guohua; Jiang, Shanshan; Sun, Liping; Li, Dequan

    2013-07-01

    Pseudomonas syringae pv. Tomato DC3000 (Pst DC3000) was the first pathogen to be demonstrated to infect Arabidopsis and to cause disease symptoms in the laboratory setting. However, the defense response to Pst DC3000 was unclear in tobacco. In this report, the expression profiles of twelve defense response-related genes were analyzed after treatment with salicylic acid (SA), jasmonic acid (JA), and pathogen Pst DC3000 by qRT-PCR. According to our results, it could be presented that the genes primarily induced by SA were also induced to higher levels after Pst DC3000 infection. SA accumulation could be induced to a higher level than that of JA after Pst DC3000 infection. In addition, SA could result in hypersensitive response (HR), which did not completely depend on accumulation of reactive oxygen species. These results indicated that tobacco mainly depended on SA signaling pathway rather than on JA signaling pathway in response to Pst DC3000. Further study demonstrated that JA could significantly inhibit the accumulation of SA and the generation of the HR induced by Pst DC3000. © 2013 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  10. The Biocontrol Efficacy of Streptomyces pratensis LMM15 on Botrytis cinerea in Tomato

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    Qinggui Lian

    2017-01-01

    Full Text Available LMM15, an actinomycete with broad spectrum antifungal activity, was isolated from a diseased tomato leaf using the baiting technique. A phylogenetic tree analysis based on similarity percentage of 16S rDNA sequences showed that the bacterium was 97.0% affiliated with the species Streptomyces pratensis. This strain was therefore coded as S. pratensis LMM15. The ferment filtrate of LMM15 had ability to inhibit mycelia growth of Botrytis cinerea and reduce lesion expansion of gray mold on detached leaves and fruits. In greenhouse experiments, both the fresh and dry weights of tomato seedlings were significantly increased with the increased concentrations of total chlorophyll. The incidence of tomato gray mold decreased by 46.35%; this was associated with the increase of proline content and malondialdehyde (MDA and the changes in defense-related enzymes on tomato leaves when the strain was sprayed on the tomato leaves 24 h prior to inoculation with pathogens. This study showed that the strain S. pratensis LMM15 could be a potential agent for controlling tomato gray mold.

  11. The Biocontrol Efficacy of Streptomyces pratensis LMM15 on Botrytis cinerea in Tomato.

    Science.gov (United States)

    Lian, Qinggui; Zhang, Jing; Gan, Liang; Ma, Qing; Zong, Zhaofeng; Wang, Yang

    2017-01-01

    LMM15, an actinomycete with broad spectrum antifungal activity, was isolated from a diseased tomato leaf using the baiting technique. A phylogenetic tree analysis based on similarity percentage of 16S rDNA sequences showed that the bacterium was 97.0% affiliated with the species Streptomyces pratensis . This strain was therefore coded as S. pratensis LMM15. The ferment filtrate of LMM15 had ability to inhibit mycelia growth of Botrytis cinerea and reduce lesion expansion of gray mold on detached leaves and fruits. In greenhouse experiments, both the fresh and dry weights of tomato seedlings were significantly increased with the increased concentrations of total chlorophyll. The incidence of tomato gray mold decreased by 46.35%; this was associated with the increase of proline content and malondialdehyde (MDA) and the changes in defense-related enzymes on tomato leaves when the strain was sprayed on the tomato leaves 24 h prior to inoculation with pathogens. This study showed that the strain S. pratensis LMM15 could be a potential agent for controlling tomato gray mold.

  12. Agrobacterium-mediated transformation of tomato with the ICE1 transcription factor gene.

    Science.gov (United States)

    Juan, J X; Yu, X H; Jiang, X M; Gao, Z; Zhang, Y; Li, W; Duan, Y D; Yang, G

    2015-01-30

    ICE1 genes play a very important role in plants in cold conditions. To improve the cold resistance of tomato, the ICE1 gene of Arabidopsis thaliana was used to construct the plant expression vector p3301-ICE1, and was overexpressed in tomato through Agrobacterium-mediated transformation. Five strains of resistant plants were obtained. PCR and half-quantitative results showed that the ICE1 gene was transferred to tomato; three strains tested positive. After low-temperature stress treatment, praline content and peroxide and catalase activities in the transgenic tomato plants were higher compared with non-transgenic controls, while malondialdehyde content was clearly lower.

  13. Inhibition of apoptic cell death induced by Pseudomonas syringae pv. Tabaci and mycotoxin fumonisin B1

    NARCIS (Netherlands)

    Iakimova, E.T.; Batchvorova, R.; Kapchina, V.; Popov, T.; Atanassov, A.; Woltering, E.J.

    2004-01-01

    The impact of programmed cell death (PCD) inhibitors on lesion formation and biochemical events in transgenic (ttr line) and non-transgenic (Nevrokop 1164) tobacco infected with Pseudomonas syringae pv. tabaci was tested. Programmed cell death in tomato cell culture was induced by Fumonisin B1 (FUM)

  14. Proposal of Xanthomonas translucens pv. pistaciae pv. nov., pathogenic to pistachio (Pistacia vera).

    Science.gov (United States)

    Giblot-Ducray, Danièle; Marefat, Alireza; Gillings, Michael R; Parkinson, Neil M; Bowman, John P; Ophel-Keller, Kathy; Taylor, Cathy; Facelli, Evelina; Scott, Eileen S

    2009-12-01

    Strains of Xanthomonas translucens have caused dieback in the Australian pistachio industry for the last 15 years. Such pathogenicity to a dicotyledonous woody host contrasts with that of other pathovars of X. translucens, which are characterized by their pathogenicity to monocotyledonous plant families. Further investigations, using DNA-DNA hybridization, gyrB gene sequencing and integron screening, were conducted to confirm the taxonomic status of the X. translucens pathogenic to pistachio. DNA-DNA hybridization provided a clear classification, at the species level, of the pistachio pathogen as a X. translucens. In the gyrB-based phylogeny, strains of the pistachio pathogen clustered among the X. translucens pathovars as two distinct lineages. Integron screening revealed that the cassette arrays of strains of the pistachio pathogen were different from those of other Xanthomonas species, and again distinguished two groups. Together with previously reported pathogenicity data, these results confirm that the pistachio pathogen is a new pathovar of X. translucens and allow hypotheses about its origin. The proposed name is Xanthomonas translucens pv. pistaciae pv. nov.

  15. [Determination of the profiles of secondary metabolites characteristic of Alternaria strains isolated from tomato].

    Science.gov (United States)

    Benavidez Rozo, Martha Elizabeth; Patriarca, Andrea; Cabrera, Gabriela; Fernández Pinto, Virginia E

    2014-01-01

    Many Alternaria species have been studied for their ability to produce bioactive secondary metabolites, such as tentoxin (TEN), some of which have toxic properties. The main food contaminant toxins are tenuazonic acid, alternariol (AOH), alternariol monomethyl ether (AME), altenuene, and altertoxins i, ii and iii. To determine the profiles of secondary metabolites characteristic of Alternaria strains isolated from tomato for their chemotaxonomic classification. The profiles of secondary metabolites were determined by HPLC MS. The Alternaria isolates obtained from spoiled tomatoes belong, according to their morphological characteristics, to the species groups Alternaria alternata, Alternaria tenuissima and Alternaria arborescens, with A. tenuissima being the most frequent. The most frequent profiles of secondary metabolites belonging to the species groups A. alternata (AOH, AME, TEN), A. tenuissima (AOH, AME, TEN, tenuazonic acid) and A. arborescens (AOH, AME, TEN, tenuazonic acid) were determined, with some isolates of the latter being able to synthesize AAL toxins. Secondary metabolite profiles are a useful tool for the differentiation of small spored Alternaria isolates not easily identifiable by their morphological characteristics. Copyright © 2013 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.

  16. Antagonistic activity of Bacillus subtilis SB1 and its biocontrol effect on tomato bacterial wilt

    Science.gov (United States)

    A potential biocontrol agent of bacterial wilt, Bacillus subtilis SB1, isolated from tomato roots, showed a broad-spectrum of antimicrobial activity in in vitro experiments. It inhibited the growth of many plant pathogens, including Ralstonia solanacearum, Xanthomonas oryzae pv. oryzae, Fusarium ox...

  17. Phenotypic and Genotypic Evaluation of Pseudomonas syringae pv. syringae Strains, Causing Citrus Blast in the West of Mazandaran and the East of Guilan

    Directory of Open Access Journals (Sweden)

    S. Sameie-Shirkadeh

    2017-01-01

    Full Text Available Introduction: P. syringae pv. syringae (P.s.s, the causal agent of blast of citrus trees, is one of the most important plant pathogens in the world. P.s.s is unique among most P. syringae pathovars according to its ability to cause disease in over 180 species of plants in several unrelated genera. Traditionally, Strains of P.s.s are identified on the basis of biochemical and nutritional tests and symptom expression in host plants. Genomic fingerprinting methods based on the polymerase chain reaction (PCR have been applied for identification and classification of plant-associated bacteria to the subspecies level. The objectives of this study were the phenotypic and molecular evaluation of P.s. pv. syringae strains causing citrus blast in the West of Mazandaran and the East of Guilan, and study of genetic diversity of P.s.s isolates of citrus by using ERIC and REP-PCR markers. Materials and Methods: During 2011 to 2012, citrus infected tissues were sampled from different orchards in the West of Mazandaran and the East of Guilan. Bacterial phenotypes were studied based on standard physiological and biochemical tests. Gram reaction was determined by potassium hydroxide solubility test (KOH test. Strains were grown on King'B medium (KB and fluorescent pigment production was evaluated. Levan formation, oxidase reaction, potato soft rot, Arginine dihydrolase and induction of the hypersensitive reaction in tobacco leaves (LOPAT tests, were done as described by Schadd et al. The standard strains of P.s. pv. syringae form IVIA were used as reference strains in this study. Pathogenicity Test was done as described by Yessad et al. Citrus seedlings were maintained in a greenhouse at 20°C. In addition, a PCR-based method was used to confirm the genus and species of bacteria by using bacterial specific primer pair’s designed for a specific gene of syringomycin B. Genetic diversity among the strains, was studied by rep-PCR fingerprinting. Genomic

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

    Science.gov (United States)

    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.

  19. Selection of halophilic bacteria for biological control of tomato gray mould caused by Botrytis cinerea

    Directory of Open Access Journals (Sweden)

    Imane BERRADA

    2013-01-01

    Full Text Available In Morocco, tomato gray mould caused by Botrytis cinerea Pers: Fr. is a serious threat for postharvest storage of tomatoes. Fifteen halophilic bacteria were evaluated for their antagonistic activity against B. cinerea: 11 Gram positive strains assigned to the genera Bacillus (9, Jeotgalibacillus (1 and Planococcus (1 and four Gram negative strains assigned to the genera Salinivibrio (1, Vibrio (2 and Photobacterium (1. In in vitro screening, 12 antifungal isolates secreted diffusible compounds, hydrolytic enzymes or volatile compounds. In vivo screening of the isolates, Bacillus safensis CCMM B582 and Bacillus oceanisediminis CCMM B584 showed permanent antagonistic activity on tomato fruits, with 100% inhibition of B. cinerea after 7 days. These two strains may offer potential for biological control of tomato gray mould.

  20. Characterization of rhizosphere bacteria for control of phytopathogenic fungi of tomato.

    Science.gov (United States)

    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.

  1. Virulence of Pseudomonas syringae pv. tomato DC3000 Is Influenced by the Catabolite Repression Control Protein Crc.

    Science.gov (United States)

    Chakravarthy, Suma; Butcher, Bronwyn G; Liu, Yingyu; D'Amico, Katherine; Coster, Matthew; Filiatrault, Melanie J

    2017-04-01

    Pseudomonas syringae infects diverse plant species and is widely used as a model system in the study of effector function and the molecular basis of plant diseases. Although the relationship between bacterial metabolism, nutrient acquisition, and virulence has attracted increasing attention in bacterial pathology, it is largely unexplored in P. syringae. The Crc (catabolite repression control) protein is a putative RNA-binding protein that regulates carbon metabolism as well as a number of other factors in the pseudomonads. Here, we show that deletion of crc increased bacterial swarming motility and biofilm formation. The crc mutant showed reduced growth and symptoms in Arabidopsis and tomato when compared with the wild-type strain. We have evidence that the crc mutant shows delayed hypersensitive response (HR) when infiltrated into Nicotiana benthamiana and tobacco. Interestingly, the crc mutant was more susceptible to hydrogen peroxide, suggesting that, in planta, the mutant may be sensitive to reactive oxygen species generated during pathogen-associated molecular pattern-triggered immunity (PTI). Indeed, HR was further delayed when PTI-induced tissues were challenged with the crc mutant. The crc mutant did not elicit an altered PTI response in plants compared with the wild-type strain. We conclude that Crc plays an important role in growth and survival during infection.

  2. Characterization of endophytic Bacillus strains from tomato plants (Lycopersicon esculentum) displaying antifungal activity against Botrytis cinerea Pers.

    Science.gov (United States)

    Kefi, Asma; Ben Slimene, Imen; Karkouch, Ines; Rihouey, Christophe; Azaeiz, Sana; Bejaoui, Marwa; Belaid, Rania; Cosette, Pascal; Jouenne, Thierry; Limam, Ferid

    2015-12-01

    Eighty endophytic bacteria were isolated from healthy tissues of roots, stems, leaves and fruits of tomato plants (Lycopersicon esculentum). Four strains, named BL1, BT5, BR8 and BF11 were selected for their antagonism against Botrytis cinerea, a phytopathogenic fungus responsible of gray mold in several important crops, with growth inhibitory activity ranging from 27 to 53%. Morphological, biochemical, and molecular parameters as 16S rDNA sequencing demonstrated that the selected bacterial strains were related to Bacillus species which are known to produce and secrete a lot of lipopeptides with strong inhibitory effect against pathogen mycelial growth. Electrospray mass spectrometry analysis showed that these strains produced heterogeneous mixture of antibiotics belonging to fengycin and surfactin for BL1 and BT5, to iturin and surfactin for BR8, to bacillomycin D, fengycin and surfactin for BF11. Furthermore, these bacteria exhibited biocontrol potential by reducing the disease severity when tested on detached leaflets. Based on their antifungal activity against Botrytis cinerea, these strains could be used for biological control of plant diseases.

  3. Defining essential processes in plant pathogenesis with Pseudomonas syringae pv. tomato DC3000 disarmed polymutants and a subset of key type III effectors.

    Science.gov (United States)

    Wei, Hai-Lei; Collmer, Alan

    2017-12-25

    Pseudomonas syringae pv. tomato DC3000 and its derivatives cause disease in tomato, Arabidopsis and Nicotiana benthamiana. The primary virulence factors include a repertoire of 29 effector proteins injected into plant cells by the type III secretion system and the phytotoxin coronatine. The complete repertoire of effector genes and key coronatine biosynthesis genes have been progressively deleted and minimally reassembled to reconstitute basic pathogenic ability in N. benthamiana, and in Arabidopsis plants that have mutations in target genes that mimic effector actions. This approach and molecular studies of effector activities and plant immune system targets have highlighted a small subset of effectors that contribute to essential processes in pathogenesis. Most notably, HopM1 and AvrE1 redundantly promote an aqueous apoplastic environment, and AvrPtoB and AvrPto redundantly block early immune responses, two conditions that are sufficient for substantial bacterial growth in planta. In addition, disarmed DC3000 polymutants have been used to identify the individual effectors responsible for specific activities of the complete repertoire and to more effectively study effector domains, effector interplay and effector actions on host targets. Such work has revealed that AvrPtoB suppresses cell death elicitation in N. benthamiana that is triggered by another effector in the DC3000 repertoire, highlighting an important aspect of effector interplay in native repertoires. Disarmed DC3000 polymutants support the natural delivery of test effectors and infection readouts that more accurately reveal effector functions in key pathogenesis processes, and enable the identification of effectors with similar activities from a broad range of other pathogens that also defeat plants with cytoplasmic effectors. © 2017 BSPP AND JOHN WILEY & SONS LTD.

  4. Cloning of a two-component signal transduction system of Xanthomonas campestris pv. phaseoli var. fuscans strain BXPF65

    DEFF Research Database (Denmark)

    Chan, JWYF; Maynard, Scott; Goodwin, PH

    1998-01-01

    A putative two-component signal transduction system was amplified and cloned from the plant pathogenic bacterium Xanthomonas campestris pv. phaseoli var. fuscans isolate BXPF65. The 620 bp amplified fragment was sequenced and analyzed with the BLAST Enhanced Alignment Utility (BEAUTY). BEAUTY...... that the putative histidine kinase has homology with conserved “transmitter” domains of sensor proteins in two-component signal transduction systems. RFLP analysis using the putative signal transduction system showed polymorphisms among the strains....

  5. Tomato bushy stunt virus (TBSV) infecting Lycopersicon esculentum.

    Science.gov (United States)

    Hafez, El Sayed E; Saber, Ghada A; Fattouh, Faiza A

    2010-01-01

    Tomato bushy stunt virus (TBSV) was detected in tomato crop (Lycopersicon esculentum) in Egypt with characteristic mosaic leaf deformation, stunting, and bushy growth symptoms. TBSV infection was confirmed serologically by ELISA and calculated incidence was 25.5%. Basic physicochemical properties of a purified TBSV Egh isolate were identical to known properties of tombusviruses of isometric 30-nm diameter particles, 41-kDa coat protein and the genome of approximately 4800 nt. This is the first TBSV isolate reported in Egypt. Cloning and partial sequencing of the isolate showed that it is more closely related to TBSV-P and TBSV-Ch than TBSV-Nf and TBSV-S strains of the virus. However, it is distinct from the above strains and could be a new strain of the virus which further confirms the genetic diversity of tombusviruses.

  6. PGPR Potentially Improve Growth of Tomato Plants in Salt-Stressed Environment

    Directory of Open Access Journals (Sweden)

    Mariam Zameer

    2016-06-01

    Full Text Available Plant growth promoting rhizobacteria are colonized bacterial species that has the capability to improve plant growth by certain direct and indirect means. Environmental factors including both biotic and abiotic stresses are among the major constraints to crop production. In the current study, the effectiveness of microbial inoculation (Bacillus megaterium for enhancing growth of tomato plants under salt stress conditions has been investigated. Significant improvement in shoot length, root length, leaf surface area, number of leaves, total weight of the shoot and root was observed in tomato plants inoculated with zm7 strain post 15 and 30 days of its application. Zm3, Zm4 and Zm6 strains improved the morphological parameters as compared to the control. Chlorophyll content a, chlorophyll content b, anthocyanin and carotenoid content was increased in tomato plants subjected to Zm7, Zm6 and Zm4 strains. Stress responsive genes; metallothionein and glutothion gene were found highly expressed in Zm7 treated tomato plants as compared to control, untreated plants. Significant correlation of anthocyanin was reported for carotenoids, chlorophyll-b, shoot weight and total weight of seedling while carotenoids were significantly correlated with leaf surface area, root length, chlorophyll-b and anthocyanin. Overall, Zm7 strain proved best for improvement in salt stressed plant’s morphological parameters and biochemical parameters as compared to control, untreated plants.

  7. Mangotoxin production of Pseudomonas syringae pv. syringae is regulated by MgoA.

    Science.gov (United States)

    Carrión, Víctor J; van der Voort, Menno; Arrebola, Eva; Gutiérrez-Barranquero, José A; de Vicente, Antonio; Raaijmakers, Jos M; Cazorla, Francisco M

    2014-02-21

    The antimetabolite mangotoxin is a key factor in virulence of Pseudomonas syringae pv. syringae strains which cause apical necrosis of mango trees. Previous studies showed that mangotoxin biosynthesis is governed by the mbo operon. Random mutagenesis led to the identification of two other gene clusters that affect mangotoxin biosynthesis. These are the gacS/gacA genes and mgo operon which harbors the four genes mgoBCAD. The current study shows that disruption of the nonribosomal peptide synthetase (NRPS) gene mgoA resulted in loss of mangotoxin production and reduced virulence on tomato leaves. Transcriptional analyses by qPCR and promoter reporter fusions revealed that mbo expression is regulated by both gacS/gacA and mgo genes. Also, expression of the mgo operon was shown to be regulated by gacS/gacA. Heterologous expression under the native promoter of the mbo operon resulted in mangotoxin production in non-producing P. syringae strains, but not in other Pseudomonas species. Also introduction of the mbo and mgo operons in nonproducing P. protegens Pf-5 did not confer mangotoxin production but did enhance transcription of the mbo promoter. From the data obtained in this study, we conclude that both mbo and mgo operons are under the control of the gacS/gacA two-component system and that the MgoA product acts as a positive regulator of mangotoxin biosynthesis.

  8. Isolation and characterization of rhizosphere bacteria for the biocontrol of the damping-off disease of tomatoes in Tunisia.

    Science.gov (United States)

    Hammami, Inés; Ben Hsouna, Anis; Hamdi, Naceur; Gdoura, Radhouane; Triki, Mohamed Ali

    2013-01-01

    Fluorescent Pseudomonas spp., isolated from tomato and pepper plants rhizosphere soil, was evaluated in vitro as a potential antagonist of fungal pathogens. Pseudomonas strains were tested against the causal agents of tomatoes damping-off (Sclerotinia sclerotiorum), root rot (Fusarium solani), and causal agents of stem canker and leaf blight (Alternaria alternata). For this purpose, 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. In addition, strains were screened for their ability to produce exoenzymes and siderophores. All the strains significantly inhibited Alternaria alternata, particularly in 25% TSA medium. Antagonistic effect on Sclerotinia sclerotiorum and Fusarium solani was greater on King B medium. Protease was produced by 30% of the strains, but no strain produced cellulase or chitinase. Finally, the selected Pseudomonas strain, Psf5, was evaluated on tomato seedling development and as a potential candidate for controlling tomato damping-off caused by Sclerotinia sclerotiorum, under growth chamber conditions. In vivo studies resulted in significant increases in plant stand as well as in root dry weight. Psf5 was able to establish and survive in tomato plants rhizosphere after 40days following the planting of bacterized seeds. © 2013 Académie des sciences. Published by Elsevier SAS. All rights reserved.

  9. The levels of nitrite and nitrate, proline and protein profiles in tomato plants infected with pseudomonas syringae

    International Nuclear Information System (INIS)

    Berber, I.; Onlu, H.

    2012-01-01

    In this study, the contents of nitrite-nitrate and free L-proline, and pathogenesis-related (PR) proteins in tomato plants following inoculation with Pseudomonas syringae pv. tomato strain were examined. The results of the nitrite and nitrate indicated that there was a reduction in the levels of nitrate in the infected tomato plants through 1-8 study days, compared with the healthy plants. On the other hands, when the nitrite amounts increased in the first and second days, the nitrite concentrations reduced in infected plants at subsequent time periods, compared with uninfected plants. The accumulation of free proline increased in the infected plants, according to control plants. The whole-cell protein profiles displayed that the levels of the protein bands of molecular masses 204.6 kDa and 69.9 kDa significantly increased in infected and uninfected plants during 2-10 study days. In additionally, in the quantities of the protein bands of molecular weights 90.3 and 79.4 kDa were observed an increase in the infected and healthy plants after the fourth day. However, the protein band of molecular weight 54.3 kDa was visible only in uninfected plants for the fourth and eighth days. Finally, the study suggest that there were the sophisticate relationships among the proline accumulation, the conversion of nitrate to nitrite and the induction of PR protein genes in the regulation of defense mechanisms toward microbial invaders. Our results also indicated that the increases in nitrite and proline contents might be useful indicator for the response toward pathogen attacks. (author)

  10. Multilocus sequence typing of Pseudomonas syringae sensu lato confirms previously described genomospecies and permits rapid identification of P. syringae pv. coriandricola and P. syringae pv. apii causing bacterial leaf spot on parsley.

    Science.gov (United States)

    Bull, Carolee T; Clarke, Christopher R; Cai, Rongman; Vinatzer, Boris A; Jardini, Teresa M; Koike, Steven T

    2011-07-01

    Since 2002, severe leaf spotting on parsley (Petroselinum crispum) has occurred in Monterey County, CA. Either of two different pathovars of Pseudomonas syringae sensu lato were isolated from diseased leaves from eight distinct outbreaks and once from the same outbreak. Fragment analysis of DNA amplified between repetitive sequence polymerase chain reaction; 16S rDNA sequence analysis; and biochemical, physiological, and host range tests identified the pathogens as Pseudomonas syringae pv. apii and P. syringae pv. coriandricola. Koch's postulates were completed for the isolates from parsley, and host range tests with parsley isolates and pathotype strains demonstrated that P. syringae pv. apii and P. syringae pv. coriandricola cause leaf spot diseases on parsley, celery, and coriander or cilantro. In a multilocus sequence typing (MLST) approach, four housekeeping gene fragments were sequenced from 10 strains isolated from parsley and 56 pathotype strains of P. syringae. Allele sequences were uploaded to the Plant-Associated Microbes Database and a phylogenetic tree was built based on concatenated sequences. Tree topology directly corresponded to P. syringae genomospecies and P. syringae pv. apii was allocated appropriately to genomospecies 3. This is the first demonstration that MLST can accurately allocate new pathogens directly to P. syringae sensu lato genomospecies. According to MLST, P. syringae pv. coriandricola is a member of genomospecies 9, P. cannabina. In a blind test, both P. syringae pv. coriandricola and P. syringae pv. apii isolates from parsley were correctly identified to pathovar. In both cases, MLST described diversity within each pathovar that was previously unknown.

  11. Isolation of Enterobacter cowanii in tomatoes after gamma irradiation

    International Nuclear Information System (INIS)

    Vicalvi, M.C.V.; Solidonio, E.G.; Silva, M.A.; Colaco, W.; Silva, G.R. da; Sena, K.X.F.R de

    2013-01-01

    The tomato is one of the most consumed fruit in the world. Bacteria of the family Enterobacteriaceae are responsible for large outbreaks of gastroenteritis. Irradiation is a physical method which reduces waste by eliminating spoilage organisms in foods. The objective of this study was to identify and determine the resistance profile of micro-organisms of the family Enterobacteriaceae from irradiated tomatoes. Were used three batches each containing 80 tomatoes, and divided in control and irradiated. The samples were individually properly identified as the irradiation dose applied. The material was subjected to irradiation with gamma rays, for irradiating with a cobalt-60 source, using doses: 1.0, 1.5 and 2 kGy (6,060 kGy/h). For microbiological analysis tomatoes were cut out, and removing the shells to obtain samples weighing 25g. Each sample was transferred to an Erlenmeyer containing sterilized water, stirring the assembly mechanically. Aliquots of the wash waters were sown in differential and selective media. After reisolation, the colonies were subjected to Gram staining then performed biochemical tests for identification. The antibiotic susceptibility tests were performed according to CLSI (Clinical Laboratory Standard Institute). It was isolated three strains of Enterobacter cowanii in tomato samples irradiated with a dose of 1.0 kGy, without isolating the other doses. As for the resistance profile, the strains were resistant to Ampicillin identified. Gamma irradiation at a dose of 1.5 and 2 kGy was effective in tomatoes as well as the micro-organism isolated after irradiation showed no profile of multidrug resistance. (author)

  12. Building Integrated PV and PV/Hybrid Products - The PV:BONUS Experience: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, H.; Pierce, L. K.

    2001-10-01

    Presented at the 2001 NCPV Program Review Meeting: Successes and lessons learned from PV:BONUS (Building Opportunities in the United States in PV). This program has funded the development of PV or PV/hybrid products for building applications.

  13. Cloning of genes required for hypersensitivity and pathogenicity in Pseudomonas syringae pv. aptata.

    Science.gov (United States)

    Minardi, P

    1995-01-01

    A genomic library of Pseudomonas syringae pv. aptata strain NCPPB 2664, which causes bacterial blight of sugar beet, lettuce and other plants, was constructed in the cosmid vector pCPP31. The 13.4 kb EcoRI fragment of the cosmid pHIR11, containing the hrp (hypersensitive response and pathogenicity) gene cluster of the closely related bacterium Pseudomonas syringae pv. syringae strain 61, was used as a probe to identify a homologous hrp gene cluster in P. syringae pv. aptata. Thirty of 2500 cosmid clones, screened by colony hybridization, gave a strong hybridization signal with the probe, but none of these conferred to the non-pathogenic bacterium, Pseudomonas fluorescens, the ability to elicit the hypersensitive response (HR) in tobacco. Southern blot analysis of EcoRI-digested genomic DNA of P. syringae pv. aptata showed hybridizing bands of 12 kb and 4.4 kb. Only a 12 kb fragment hybridized in digests of the cosmids. Cosmid clone pCPP1069 was mutagenized with Tn10-minitet and marker-exchanged into the genome of P. syringae pv. aptata. Three resulting prototrophic mutant strains failed to elicit the HR in tobacco and to cause disease in lettuce. The DNA flanking the Tn10-minitet insertions from mutated derivatives of pCPP1069 hybridized with the 10.6 kb Bg/II fragment of pHIR11. These results indicate that P. syringae pv. aptata harbours hrp genes that are similar to, but arranged differently from, homologous hrp genes of P. syringae pv. syringae.

  14. Immunocytochemical localization of HrpA and HrpZ supports a role for the Hrp pilus in the transfer of effector proteins from Pseudomonas syringae pv. tomato across the host plant cell wall.

    Science.gov (United States)

    Brown, I R; Mansfield, J W; Taira, S; Roine, E; Romantschuk, M

    2001-03-01

    The Hrp pilus, composed of HrpA subunits, is an essential component of the type III secretion system in Pseudomonas syringae. We used electron microscopy (EM) and immunocytochemistry to examine production of the pilus in vitro from P. syringae pv. tomato strain DC3000 grown under hrp-inducing conditions on EM grids. Pili, when labeled with antibodies to HrpA, developed rapidly in a nonpolar manner shortly after the detection of the hrpA transcript and extended up to 5 microm into surrounding media. Structures at the base of the pilus were clearly differentiated from the basal bodies of flagella. The HrpZ protein, also secreted via the type III system, was found by immunogold labeling to be associated with the pilus in vitro. Accumulation and secretion of HrpA and HrpZ were also examined quantitatively after the inoculation of wild-type DC3000 and hrpA and hrpZ mutants into leaves of Arabidopsis thaliana. The functional pilus crossed the plant cell wall to generate tracks of immunogold labeling for HrpA and HrpZ. Mutants that produced HrpA but did not assemble pili were nonpathogenic, did not secrete HrpA protein, and were compromised for the accumulation of HrpZ. A model is proposed in which the rapidly elongating Hrp pilus acts as a moving conveyor, facilitating transfer of effector proteins from bacteria to the plant cytoplasm across the formidable barrier of the plant cell wall.

  15. Pepino mosaic virus, a first report of a virus infecting tomato in Syria

    Directory of Open Access Journals (Sweden)

    Ahmad Fakhro

    2010-05-01

    Full Text Available This is the first report of Pepino mosaic virus (PepMV occurring in tomato plants grown in plastic greenhouses in a Mediterranean city in Syria. One tomato fruit from sixty samples tested positive for this virus by DAS-ELISA. Biotest assay, RT-PCR, and sequencing confirmed the presence of PepMV. The highest sequence identity of the Syrian isolate was with the EU-tomato strains of PepMV.

  16. Modular Study of the Type III Effector Repertoire in Pseudomonas syringae pv. tomato DC3000 Reveals a Matrix of Effector Interplay in Pathogenesis.

    Science.gov (United States)

    Wei, Hai-Lei; Zhang, Wei; Collmer, Alan

    2018-05-08

    The bacterial pathogen Pseudomonas syringae pv. tomato DC3000 suppresses the two-tiered innate immune system of Nicotiana benthamiana and other plants by injecting a complex repertoire of type III secretion effector (T3E) proteins. Effectorless polymutant DC3000D36E was used with a modularized system for native delivery of the 29 DC3000 T3Es singly and in pairs. Assays of the performance of this T3E library in N. benthamiana leaves revealed a matrix of T3E interplay, with six T3Es eliciting death and eight others variously suppressing the death activity of the six. The T3E library was also interrogated for effects on DC3000D36E elicitation of a reactive oxygen species burst, for growth in planta, and for T3Es that reversed these effects. Pseudomonas fluorescens and Agrobacterium tumefaciens heterologous delivery systems yielded notably different sets of death-T3Es. The DC3000D36E T3E library system highlights the importance of 13 T3Es and their interplay in interactions with N. benthamiana. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

  17. Assessing European egg parasitoids as a mean of controlling the invasive South American tomato pinworm Tuta absoluta.

    Directory of Open Access Journals (Sweden)

    Anaïs Chailleux

    Full Text Available The South American tomato pinworm (Tuta absoluta has recently invaded Europe and is rapidly spreading in the Afro-Eurasian continent where it is becoming a major pest on tomato crops. Laboratory tests were undertaken to evaluate the potential of 29 European strains of Trichogramma parasitoids to control T. absoluta. In addition to the host itself, the host plant (tomato was used during the laboratory tests in order to increase the chance of selecting the best parasitoid strains. Trichogramma females were placed with T. absoluta eggs on a tomato leaflet in tubes. We compared the parasitism of T. absoluta by the various Trichogramma species tested to the Trichogramma species currently commercially available for the pest control in Europe, i.e. Trichogramma achaeae. Thereafter, the more promising strains were tested on a larger scale, in mesocosm (i.e. cages in greenhouses and in greenhouse compartments to evaluate efficiency of laboratory selected strains under cropping conditions. The most efficient strain from the laboratory screening trials did not perform as efficiently under the greenhouse conditions. We discuss differences in parasitism levels among species and strains and among the different scales tested in the experiments, as well as implications of these results for further screening for biocontrol agents.

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

    Science.gov (United States)

    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].

  19. Thermal inactivation kinetics of Bacillus coagulans spores in tomato juice.

    Science.gov (United States)

    Peng, Jing; Mah, Jae-Hyung; Somavat, Romel; Mohamed, Hussein; Sastry, Sudhir; Tang, Juming

    2012-07-01

    The thermal characteristics of the spores and vegetative cells of three strains of Bacillus coagulans (ATCC 8038, ATCC 7050, and 185A) in tomato juice were evaluated. B. coagulans ATCC 8038 was chosen as the target microorganism for thermal processing of tomato products due to its spores having the highest thermal resistance among the three strains. The thermal inactivation kinetics of B. coagulans ATCC 8038 spores in tomato juice between 95 and 115°C were determined independently in two different laboratories using two different heating setups. The results obtained from both laboratories were in general agreement, with z-values (z-value is defined as the change in temperature required for a 10-fold reduction of the D-value, which is defined as the time required at a certain temperature for a 1-log reduction of the target microorganisms) of 8.3 and 8.7°C, respectively. The z-value of B. coagulans 185A spores in tomato juice (pH 4.3) was found to be 10.2°C. The influence of environmental factors, including cold storage time, pH, and preconditioning, upon the thermal resistance of these bacterial spores is discussed. The results obtained showed that a storage temperature of 4°C was appropriate for maintaining the viability and thermal resistance of B. coagulans ATCC 8038 spores. Acidifying the pH of tomato juice decreased the thermal resistance of these spores. A 1-h exposure at room temperature was considered optimal for preconditioning B. coagulans ATCC 8038 spores in tomato juice.

  20. PV-CAD: an integrated tool for designing PV facades; PV-CAD - Ein integriertes Werkzeug zur Auslegung von PV-Fassaden

    Energy Technology Data Exchange (ETDEWEB)

    Giese, H.; Viotto, M. [Inst. fuer Solare Energieversorgungstechnik (ISET) e.V., Kassel (Germany); Esser, M.; Pukrop, D. [Univ. Oldenburg (Germany). Abt. Energie- und Halbleiterforschung; Stellbogen, D. [Zentrum fuer Sonnenergie- und Wasserstoff-Forschung, Stuttgart (Germany)

    1997-12-31

    PV-CAD provides PV system planners with a practice-oriented tool for an efficient design of PV facades. Being compatible with the standard programmes of the architects` and electrical engineering sectors it can be used on already existing systems and allows the user to draw on previously acquired knowedge. Its open interfaces permit the integration of further design tools. PV CAD works under Microsoft Windows for which it has the necessary graphic user interface. Its compliance to PC standards opens up a wide range of applications and permits its use also on inexpensive computers. Thanks to its promotion by the Federal Ministry for Education, Science, Research, and Technology under the research project ``Computer programmes for the design of photovoltaic facades`` PV-CAD is available at a moderate price. PV-CAD permits an efficient planning of solar facades and therefore has the potential to stimulate the use of PV on buildings. (orig.) [Deutsch] Mit PV-CAD steht dem Anlagenplaner ein anwendungsorientiertes Werkzeug zur Verfuegung, das eine rationelle Auslegung von PV-Fassaden ermoeglicht. Die Kompatibilitaet zu Standardprogrammen aus dem Architektur- und Elektrosektor erlaubt die Nutzung bereits vorhandener Systeme und damit erworbener Kenntnisse. Offene Schnittstellen gestatten die Einbindung weiterer Entwurfswerkzeuge. PV-CAD arbeitet unter Microsoft-Windows und verfuegt ueber die entsprechende grafische Benutzerschnittstelle. Die Kompatibilitaet zum PC-Standard eroeffnet eine sehr breite Anwenderbasis und ermoeglicht den Einsatz des Programms auch auf preiswerten Rechnern. Aufgrund der Foerderung durch das Bundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie im Rahmen des Forschungsprojekts `Rechnerprogramm zur Auslegung von Photovoltaik-Fassaden` steht PV-CAD preiswert zur Verfuegung. PV-CAD ermoeglicht eine effiziente Planung von Solarfassaden und kann daher dem PV-Einsatz in Gebaeuden weitere Impulse geben. (orig.)

  1. PV-WEB: internet-based PV information tool

    International Nuclear Information System (INIS)

    Cowley, P.

    2003-01-01

    This report gives details of a project to create a web-based information system on photovoltaic (PV) systems for the British PV Association (PV-UK) for use by decision makers in government, the utilities, and the housing and construction sectors. The project, which aims to provide an easily accessible tool for UK companies, promote PV technology, increase competitiveness, and identify market opportunities, is described. The design of the web site and its implementation and the evolution are discussed, along with the maintenance of the site by PV-UK and the opportunities offered to PV-UK Members

  2. PV-WEB: internet-based PV information tool

    Energy Technology Data Exchange (ETDEWEB)

    Cowley, P

    2003-07-01

    This report gives details of a project to create a web-based information system on photovoltaic (PV) systems for the British PV Association (PV-UK) for use by decision makers in government, the utilities, and the housing and construction sectors. The project, which aims to provide an easily accessible tool for UK companies, promote PV technology, increase competitiveness, and identify market opportunities, is described. The design of the web site and its implementation and the evolution are discussed, along with the maintenance of the site by PV-UK and the opportunities offered to PV-UK Members.

  3. Characterization of antagonistic-potential of two Bacillus strains and their biocontrol activity against Rhizoctonia solani in tomato.

    Science.gov (United States)

    Solanki, Manoj Kumar; Singh, Rajesh Kumar; Srivastava, Supriya; Kumar, Sudheer; Kashyap, Prem Lal; Srivastava, Alok K

    2015-01-01

    To investigate the biocontrol mechanism of two antagonistic Bacillus strains (Bacillus subtilis MB14 and Bacillus amyloliquefaciens MB101), three in vitro antagonism assays were screened and the results were concluded that both strains inhibited Rhizoctonia solani growth in a similar manner by dual culture assay, but the maximum percent of inhibition only resulted with MB101 by volatile and diffusible metabolite assays. Moreover, cell free supernatant (CFS) of MB101 also showed significant (p > 0.05) growth inhibition as compared to MB14, when 10 and 20% CFS mix with the growth medium of R. solani. After in vitro-validation, both strains were evaluated under greenhouse and the results concluded that strain MB101 had significant biocontrol potential as compared to MB14. Strain MB101 was enhanced the plant height, biomass and chlorophyll content of tomato plant through a higher degree of root colonization. In field trials, strain MB101 showed higher lessening in root rot symptoms with significant fruit yield as compare to strain MB14 and infected control. Next to the field study, the presence of four antibiotic genes (srfAA, fenD, ituC, and bmyB) also concluded the antifungal nature of both Bacillus strains. Phylogenetic analysis of protein sequences revealed a close relatedness of three genes (srfAA, fenD, and ituC) with earlier reported sequences of B. subtilis and B. amyloliquefaciens. However, bmyB showed heterogeneity in among both strains (MB14 and MB101) and it may be concluded that higher degree of antagonism, root colonization and different antibiotic producing genes may play an important role in biocontrol mechanism of strain MB101. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Visualization of N-acylhomoserine lactone-mediated cell-cell communication between bacteria colonizing the tomato rhizosphere

    DEFF Research Database (Denmark)

    Steidle, A.; Sigl, K.; Schuhegger, R.

    2001-01-01

    developed and characterized novel Gfp-based monitor strains that allow in situ visualization of AHL-mediated communication between individual cells in the plant rhizosphere. For this purpose, three Gfp-based AHL sensor plasmids that respond to different spectra of AHL molecules were transferred into AHL......-negative derivatives of Pseudomonas putida IsoF and Serratia liquefaciens MG1, two strains that are capable of colonizing tomato roots. These AHL monitor strains were used to visualize communication between defined bacterial populations in the rhizosphere of axenically grown tomato plants. Furthermore, we integrated...

  5. The Arabidopsis thaliana cysteine-rich receptor-like kinase CRK20 modulates host responses to Pseudomonas syringae pv. tomato DC3000 infection.

    Science.gov (United States)

    Ederli, Luisa; Madeo, Laura; Calderini, Ornella; Gehring, Chris; Moretti, Chiaraluce; Buonaurio, Roberto; Paolocci, Francesco; Pasqualini, Stefania

    2011-10-15

    In plants, the cysteine-rich repeat kinases (CRKs) are a sub-family of receptor-like protein kinases that contain the DUF26 motif in their extracellular domains. It has been shown that in Arabidopsis thaliana, CRK20 is transcriptionally induced by pathogens, salicylic acid and ozone (O(3)). However, its role in responses to biotic and abiotic stress remains to be elucidated. To determine the function of CRK20 in such responses, two CRK20 loss-of-function mutants, crk20-1 and crk20-2, were isolated from public collections of Arabidopsis T-DNA tagged lines and examined for responses to O(3) and Pseudomonas syringae pv. tomato (Pst) DC3000. crk20-1 and crk20-2 showed similar O(3) sensitivities and no differences in the expression of defense genes when compared with the wild-type. However, pathogen growth was significantly reduced, while there were no differences in the induction of salicylic acid related defense genes or salicylic acid accumulation. Furthermore, correlation analysis of CRK20 gene expression suggests that it has a role in the control of H(2)O and/or nutrient transport. We therefore propose that CRK20 promotes conditions that are favorable for Pst DC3000 growth in Arabidopsis, possibly through the regulation of apoplastic homeostasis, and consequently, of the environment of this biotrophic pathogen. Copyright © 2011 Elsevier GmbH. All rights reserved.

  6. The Arabidopsis thaliana cysteine-rich receptor-like kinase CRK20 modulates host responses to Pseudomonas syringae pv. tomato DC3000 infection

    KAUST Repository

    Ederli, Luisa

    2011-10-01

    In plants, the cysteine-rich repeat kinases (CRKs) are a sub-family of receptor-like protein kinases that contain the DUF26 motif in their extracellular domains. It has been shown that in Arabidopsis thaliana, CRK20 is transcriptionally induced by pathogens, salicylic acid and ozone (O3). However, its role in responses to biotic and abiotic stress remains to be elucidated. To determine the function of CRK20 in such responses, two CRK20 loss-of-function mutants, crk20-1 and crk20-2, were isolated from public collections of Arabidopsis T-DNA tagged lines and examined for responses to O3 and Pseudomonas syringae pv. tomato (Pst) DC3000. crk20-1 and crk20-2 showed similar O3 sensitivities and no differences in the expression of defense genes when compared with the wild-type. However, pathogen growth was significantly reduced, while there were no differences in the induction of salicylic acid related defense genes or salicylic acid accumulation. Furthermore, correlation analysis of CRK20 gene expression suggests that it has a role in the control of H2O and/or nutrient transport. We therefore propose that CRK20 promotes conditions that are favorable for Pst DC3000 growth in Arabidopsis, possibly through the regulation of apoplastic homeostasis, and consequently, of the environment of this biotrophic pathogen. © 2011 Elsevier GmbH.

  7. Methyl salicylate production in tomato affects biotic interactions.

    Science.gov (United States)

    Ament, Kai; Krasikov, Vladimir; Allmann, Silke; Rep, Martijn; Takken, Frank L W; Schuurink, Robert C

    2010-04-01

    The role of methyl salicylate (MeSA) production was studied in indirect and direct defence responses of tomato (Solanum lycopersicum) to the spider mite Tetranychus urticae and the root-invading fungus Fusarium oxysporum f. sp. lycopersici, respectively. To this end, we silenced the tomato gene encoding salicylic acid methyl transferase (SAMT). Silencing of SAMT led to a major reduction in SAMT expression and MeSA emission upon herbivory by spider mites, without affecting the induced emission of other volatiles (terpenoids). The predatory mite Phytoseiulus persimilis, which preys on T. urticae, could not discriminate between infested and non-infested SAMT-silenced lines, as it could for wild-type tomato plants. Moreover, when given the choice between infested SAMT-silenced and infested wild-type plants, they preferred the latter. These findings are supportive of a major role for MeSA in this indirect defence response of tomato. SAMT-silenced tomato plants were less susceptible to a virulent strain of F. oxysporum f. sp. lycopersici, indicating that the direct defense responses in the roots are also affected in these plants. Our studies show that the conversion of SA to MeSA can affect both direct and indirect plant defence responses.

  8. Pseudomonas savastanoi pv. savastanoi: some like it knot.

    Science.gov (United States)

    Ramos, Cayo; Matas, Isabel M; Bardaji, Leire; Aragón, Isabel M; Murillo, Jesús

    2012-12-01

    Pseudomonas savastanoi pv. savastanoi is the causal agent of olive (Olea europaea) knot disease and an unorthodox member of the P. syringae complex, causing aerial tumours instead of the foliar necroses and cankers characteristic of most members of this complex. Olive knot is present wherever olive is grown; although losses are difficult to assess, it is assumed that olive knot is one of the most important diseases of the olive crop. The last century witnessed a large number of scientific articles describing the biology, epidemiology and control of this pathogen. However, most P. savastanoi pv. savastanoi strains are highly recalcitrant to genetic manipulation, which has effectively prevented the pathogen from benefitting from the scientific progress in molecular biology that has elevated the foliar pathogens of the P. syringae complex to supermodels. A number of studies in recent years have made significant advances in the biology, ecology and genetics of P. savastanoi pv. savastanoi, paving the way for the molecular dissection of its interaction with other nonpathogenic bacteria and their woody hosts. The selection of a genetically pliable model strain was soon followed by the development of rapid methods for virulence assessment with micropropagated olive plants and the analysis of cellular interactions with the plant host. The generation of a draft genome of strain NCPPB 3335 and the closed sequence of its three native plasmids has allowed for functional and comparative genomic analyses for the identification of its pathogenicity gene complement. This includes 34 putative type III effector genes and genomic regions, shared with other pathogens of woody hosts, which encode metabolic pathways associated with the degradation of lignin-derived compounds. Now, the time is right to explore the molecular basis of the P. savastanoi pv. savastanoi-olive interaction and to obtain insights into why some pathovars like it necrotic and why some like it knot

  9. Arabidopsis AtERF15 positively regulates immunity against Pseudomonas syringae pv. tomato DC3000 and Botrytis cinerea

    Directory of Open Access Journals (Sweden)

    Huijuan eZhang

    2015-09-01

    Full Text Available Upon pathogen infection, activation of immune response requires effective transcriptional reprogramming that regulates inducible expression of a large set of defense genes. A number of ethylene-responsive factor transcription factors have been shown to play critical roles in regulating immune responses in plants. In the present study, we explored the functions of Arabidopsis AtERF15 in immune responses against Pseudomonas syringae pv. tomato (Pst DC3000, a (hemibiotrophic bacterial pathogen, and Botrytis cinerea, a necrotrophic fungal pathogen. Expression of AtERF15 was induced by infection of Pst DC3000 and B. cinerea and by treatments with salicylic acid (SA and methyl jasmonate. Biochemical assays demonstrated that AtERF15 is a nucleus-localized transcription activator. The AtERF15-overexpressing (AtERF15-OE plants displayed enhanced resistance while the AtERF15-RNAi plants exhibited decreased resistance against Pst DC3000 and B. cinerea. Meanwhile, Pst DC3000- or B. cinerea-induced expression of defense genes was upregulated in AtERF15-OE plants but downregulated in AtERF15-RNAi plants, as compared to the expression in wild type plants. In response to infection with B. cinerea, the AtERF15-OE plants accumulated less reactive oxygen species (ROS while the AtERF15-RNAi plants accumulated more ROS. The flg22- and chitin-induced oxidative burst was abolished and expression levels of the pattern-triggered immunity-responsive genes AtFRK1 and AtWRKY53 were suppressed in AtER15-RNAi plants upon treatment with flg22 or chitin. Furthermore, SA-induced defense response was also partially impaired in the AtERF15-RNAi plants. These data demonstrate that AtERF15 is a positive regulator of multiple layers of the immune responses in Arabidopsis.

  10. Inhibitory effect and possible mechanism of a Pseudomonas strain QBA5 against gray mold on tomato leaves and fruits caused by Botrytis cinerea.

    Science.gov (United States)

    Gao, Pan; Qin, Jiaxing; Li, Delong; Zhou, Shanyue

    2018-01-01

    The fungal pathogen Botrytis cinerea causes gray mold disease on various hosts, which results in serious economic losses. Over the past several decades, many kinds of fungicides have been used to successfully control the disease. Meanwhile, the uses of fungicides lead to environmental pollution as well as a potential threat to the human health by the chemical residues in tomato fruit. Also, the gray mold disease is difficult to control with fungicides. Therefore, exploring alternative measures such as biological controls could be the best choice to control the disease and alleviate damages caused by fungicides. In this study, we isolated and identified a novel Pseudomonas strain termed as QBA5 from healthy tomato plant based on the morphological, biochemical characteristics and molecular detection. The antifungal activity assays revealed that, in the presence of QBA5, conidia germination, germ tube elongation and mycelial growth of B. cinerea were significantly inhibited. Most importantly, QBA5 exerted a significant preventive effectiveness against gray mold on tomato fruits and plants. The possible mechanism of QBA5 involved in the inhibition of B. cinerea was investigated. It revealed that the conidia plasma membrane of B. cinerea was severely damaged by QBA5. Further, four different antifungal compounds in the supernatant of QBA5 were separated by preparative high performance liquid chromatography (PHPLC). Overall, the data indicate that there is a considerable potential for QBA5 to reduce the damage caused by gray mold disease on tomato.

  11. Inhibitory effect and possible mechanism of a Pseudomonas strain QBA5 against gray mold on tomato leaves and fruits caused by Botrytis cinerea.

    Directory of Open Access Journals (Sweden)

    Pan Gao

    Full Text Available The fungal pathogen Botrytis cinerea causes gray mold disease on various hosts, which results in serious economic losses. Over the past several decades, many kinds of fungicides have been used to successfully control the disease. Meanwhile, the uses of fungicides lead to environmental pollution as well as a potential threat to the human health by the chemical residues in tomato fruit. Also, the gray mold disease is difficult to control with fungicides. Therefore, exploring alternative measures such as biological controls could be the best choice to control the disease and alleviate damages caused by fungicides. In this study, we isolated and identified a novel Pseudomonas strain termed as QBA5 from healthy tomato plant based on the morphological, biochemical characteristics and molecular detection. The antifungal activity assays revealed that, in the presence of QBA5, conidia germination, germ tube elongation and mycelial growth of B. cinerea were significantly inhibited. Most importantly, QBA5 exerted a significant preventive effectiveness against gray mold on tomato fruits and plants. The possible mechanism of QBA5 involved in the inhibition of B. cinerea was investigated. It revealed that the conidia plasma membrane of B. cinerea was severely damaged by QBA5. Further, four different antifungal compounds in the supernatant of QBA5 were separated by preparative high performance liquid chromatography (PHPLC. Overall, the data indicate that there is a considerable potential for QBA5 to reduce the damage caused by gray mold disease on tomato.

  12. Effect of pre-sowing laser biostimulation of seeds on physico-chemical properties of glasshouse tomato fruits

    International Nuclear Information System (INIS)

    Koper, R.; Rybak, P.

    2000-01-01

    Paper presented results of study on the effect of pre-sowing laser biostimulation of glasshouse tomato seeds, Recento cultivar, on physico-chemical properties of yielded fruits. Tomato fruit resistance to elastic strains was tested in laboratory as well as the extract content and total acidity of fruits were analysed. Positive influence of laser treatment on tested tomato fruit properties was noted

  13. Genetic diversity of Xanthomonas axonopodis pv. citri based on plasmid profile and pulsed field gel electrophoresis

    Directory of Open Access Journals (Sweden)

    Carvalho Flávia Maria de Souza

    2005-01-01

    Full Text Available Xanthomonas axonopodis pv. citri strains that cause disease in citrus were investigated by pulsed field and plasmid profile analysis. For the first method, genomic DNA was digested by the rare-cutting enzymes Xba I and Vsp I. The strains evaluated were collected in seven different States of Brazil and in Argentina, Bolivia, Paraguay and Uruguay. Genetic variability was found among strains of X. axonopodis pv. citri from different geographical areas Argentina, Bolivia and Uruguay, with similarities varying from 0.62 to 0.83. However, the strains collected in Brazil, despite being from different States, have shown a genetic similarity ranging from 0.83 to 1.00. Cluster analysis showed a relationship between genomic similarity and geographical origin of the strains. Plasmids were observed in all strains, with a total of five different plasmids, with sizes between 57.7 and 83.0 kilobases. The 72.6 kb plasmid was the most frequent, present in 15 out of 22 strains, while the 68.1 kb plasmid was observed in two strains only. Although the plasmid diversity detected in the present study was not very great, the X. axonopodis pv. citri strains evaluated showed a considerable degree of diversity with regard to this extrachromosomal genetic element.

  14. PV and PV/hybrid products for buildings

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, H. P.; Hayter, S. J.; Martin, R. L., Pierce, L. K.

    2000-05-15

    Residential, commercial, and industrial buildings combined are the largest consumers of electricity in the United States and represent a significant opportunity for photovoltaic (PV) and PV/hybrid systems. The U.S. Department of Energy (DOE) is conducting a phased research and product development program, Building Opportunities in the United States for Photovoltaics (PV:BONUS), focused on this market sector. The purpose of the program is to develop technologies and foster business arrangements integrating cost-effective PV or hybrid products into buildings. The first phase was completed in 1996 and a second solicitation, PV:BONUS2, was initiated during 1997. These projects are resulting in a variety of building-integrated products. This paper summarizes the recent progress of the seven firms and collaborative teams currently participating in PV:BONUS2 and outlines planned work for the final phase of their work.

  15. Identification and distribution of Tomato yellow leaf curl virus TYLCV ...

    African Journals Online (AJOL)

    SAM

    2014-03-26

    Mar 26, 2014 ... Analysis of samples harvested in 2001-2002 showed that infection of tomato crops was more common in the southwest than in the north (Tahiri et al., 2007). The sequence analysis revealed the existence of the. Spanish strain of TYLCSV and of two genetically different strains of TYLCV. The Spanish origin ...

  16. Expression of Vitis amurensis VaERF20 in Arabidopsis thaliana Improves Resistance to Botrytis cinerea and Pseudomonas syringae pv. Tomato DC3000

    Directory of Open Access Journals (Sweden)

    Mengnan Wang

    2018-03-01

    Full Text Available Ethylene response factor (ERF transcription factors play important roles in regulating immune responses in plants. In our study, we characterized a member of the ERF transcription factor family, VaERF20, from the Chinese wild Vitis genotype, V. amurensis Rupr “Shuangyou”. Phylogenetic analysis indicated that VaERF20 belongs to group IXc of the ERF family, in which many members are known to contribute to fighting pathogen infection. Consistent with this, expression of VaERF20 was induced by treatment with the necrotrophic fungal pathogen Botrytis cinerea (B. cinerea in “Shuangyou” and V. vinifera “Red Globe”. Arabidopsis thaliana plants over-expressing VaERF20 displayed enhanced resistance to B. cinerea and the bacterium Pseudomonas syringae pv. tomato (Pst DC3000. Patterns of pathogen-induced reactive oxygen species (ROS accumulation were entirely distinct in B. cinerea and PstDC3000 inoculated plants. Examples of both salicylic acid (SA and jasmonic acid/ethylene (JA/ET responsive defense genes were up-regulated after B. cinerea and PstDC3000 inoculation of the VaERF20-overexpressing transgenic A. thaliana plants. Evidence of pattern-triggered immunity (PTI, callose accumulation and stomatal defense, together with increased expression of PTI genes, was also greater in the transgenic lines. These data indicate that VaERF20 participates in various signal transduction pathways and acts as an inducer of immune responses.

  17. DES-TOMATO: A Knowledge Exploration System Focused On Tomato Species

    KAUST Repository

    Salhi, Adil

    2017-07-14

    Tomato is the most economically important horticultural crop used as a model to study plant biology and particularly fruit development. Knowledge obtained from tomato research initiated improvements in tomato and, being transferrable to other such economically important crops, has led to a surge of tomato-related research and published literature. We developed DES-TOMATO knowledgebase (KB) for exploration of information related to tomato. Information exploration is enabled through terms from 26 dictionaries and combination of these terms. To illustrate the utility of DES-TOMATO, we provide several examples how one can efficiently use this KB to retrieve known or potentially novel information. DES-TOMATO is free for academic and nonprofit users and can be accessed at http://cbrc.kaust.edu.sa/des_tomato/, using any of the mainstream web browsers, including Firefox, Safari and Chrome.

  18. DES-TOMATO: A Knowledge Exploration System Focused On Tomato Species

    KAUST Repository

    Salhi, Adil; Negrã o, Só nia; Essack, Magbubah; Morton, Mitchell J. L.; Bougouffa, Salim; Mohamad Razali, Rozaimi; Radovanovic, Aleksandar; Marchand, Benoit; Kulmanov, Maxat; Hoehndorf, Robert; Tester, Mark A.; Bajic, Vladimir B.

    2017-01-01

    Tomato is the most economically important horticultural crop used as a model to study plant biology and particularly fruit development. Knowledge obtained from tomato research initiated improvements in tomato and, being transferrable to other such economically important crops, has led to a surge of tomato-related research and published literature. We developed DES-TOMATO knowledgebase (KB) for exploration of information related to tomato. Information exploration is enabled through terms from 26 dictionaries and combination of these terms. To illustrate the utility of DES-TOMATO, we provide several examples how one can efficiently use this KB to retrieve known or potentially novel information. DES-TOMATO is free for academic and nonprofit users and can be accessed at http://cbrc.kaust.edu.sa/des_tomato/, using any of the mainstream web browsers, including Firefox, Safari and Chrome.

  19. Response of Various Tomato Genotypes to Begomovirus Infection and Its Improved Diagnostic

    Directory of Open Access Journals (Sweden)

    NOOR AIDAWATI

    2007-09-01

    Full Text Available Begomovirus infection was identified from tomato growing areas in West Java (Bogor, Central Java (Boyolali, and D.I. Yogyakarta (Kaliurang. Efforts to reduce the infection among others are planting resistance varieties. This research was undertaken to evaluate 14 tomato genotypes for their response to the infection. Dot blot hybridization using nonradioactive (digoxigenin DNA probe was employed to determine the presence of begomovirus in inoculated plants. Polymerase chain reaction-amplified product of DNA clone of tobacco leaf curl virus –Indonesia was used as a source of DNA probe. All of tomato genotypes evaluated in this study was infected separately by three strain of begomovirus (GVPSlm, GVABy, GVCBgr. Tomato genotypes Bonanza, Jelita, Safira, Permata, Presto, PSPT 8, PSPT 5B, Apel-Belgia, Karibia, Mitra, PSPT 9, Marta, and PSPT 2, showed susceptible or highly susceptible response to the three strains of begomovirus. Exception to those was shown by cv. Intan which resulted in moderate resistance when inoculated with GVCBgr although it resulted susceptible response with the other two strains. Dot-blot hybridization technique was proved to be a powerful tool to detect begomovirus infection in plants showing symptom as well as symptom-less plants. Accumulation of the virus in those plants was relatively high, except in cv. Bonanza and Apel-Belgia. Dot-blot hybridization technique using DIG-labeled DNA probe was able to detect begomovirus DNA in infected tissue up to 10−2 dilution factor.

  20. 21 CFR 73.585 - Tomato lycopene extract; tomato lycopene concentrate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Tomato lycopene extract; tomato lycopene... SERVICES GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Foods § 73.585 Tomato lycopene extract; tomato lycopene concentrate. (a) Identity. (1) The color additive tomato lycopene extract is a...

  1. Suppression of Plant Immune Responses by the Pseudomonas savastanoi pv. savastanoi NCPPB 3335 Type III Effector Tyrosine Phosphatases HopAO1 and HopAO2

    Directory of Open Access Journals (Sweden)

    María Pilar Castañeda-Ojeda

    2017-05-01

    Full Text Available The effector repertoire of the olive pathogen P. savastanoi pv. savastanoi NCPPB 3335 includes two members of the HopAO effector family, one of the most diverse T3E families of the P. syringae complex. The study described here explores the phylogeny of these dissimilar members, HopAO1 and HopAO2, among the complex and reveals their activities as immune defense suppressors. Although HopAO1 is predominantly encoded by phylogroup 3 strains isolated from woody organs of woody hosts, both HopAO1 and HopAO2 are phylogenetically clustered according to the woody/herbaceous nature of their host of isolation, suggesting host specialization of the HopAO family across the P. syringae complex. HopAO1 and HopAO2 translocate into plant cells and show hrpL-dependent expression, which allows their classification as actively deployed type III effectors. Our data also show that HopAO1 and HopAO2 possess phosphatase activity, a hallmark of the members of this family. Both of them exert an inhibitory effect on early plant defense responses, such as ROS production and callose deposition, and are able to suppress ETI responses induced by the effectorless polymutant of P. syringae pv. tomato DC3000 (DC3000D28E in Nicotiana. Moreover, we demonstrate that a ΔhopAO1 mutant of P. savastanoi NCPBB 3335 exhibits a reduced fitness and virulence in olive plants, which supports the relevance of this effector during the interaction of this strain with its host plants. This work contributes to the field with the first report regarding functional analysis of HopAO homologs encoded by P. syringae or P. savastanoi strains isolated from woody hosts.

  2. Suppression of Plant Immune Responses by the Pseudomonas savastanoi pv. savastanoi NCPPB 3335 Type III Effector Tyrosine Phosphatases HopAO1 and HopAO2

    Science.gov (United States)

    Castañeda-Ojeda, María Pilar; Moreno-Pérez, Alba; Ramos, Cayo; López-Solanilla, Emilia

    2017-01-01

    The effector repertoire of the olive pathogen P. savastanoi pv. savastanoi NCPPB 3335 includes two members of the HopAO effector family, one of the most diverse T3E families of the P. syringae complex. The study described here explores the phylogeny of these dissimilar members, HopAO1 and HopAO2, among the complex and reveals their activities as immune defense suppressors. Although HopAO1 is predominantly encoded by phylogroup 3 strains isolated from woody organs of woody hosts, both HopAO1 and HopAO2 are phylogenetically clustered according to the woody/herbaceous nature of their host of isolation, suggesting host specialization of the HopAO family across the P. syringae complex. HopAO1 and HopAO2 translocate into plant cells and show hrpL-dependent expression, which allows their classification as actively deployed type III effectors. Our data also show that HopAO1 and HopAO2 possess phosphatase activity, a hallmark of the members of this family. Both of them exert an inhibitory effect on early plant defense responses, such as ROS production and callose deposition, and are able to suppress ETI responses induced by the effectorless polymutant of P. syringae pv. tomato DC3000 (DC3000D28E) in Nicotiana. Moreover, we demonstrate that a ΔhopAO1 mutant of P. savastanoi NCPBB 3335 exhibits a reduced fitness and virulence in olive plants, which supports the relevance of this effector during the interaction of this strain with its host plants. This work contributes to the field with the first report regarding functional analysis of HopAO homologs encoded by P. syringae or P. savastanoi strains isolated from woody hosts. PMID:28529516

  3. Impacts of PV Array Sizing on PV Inverter Lifetime and Reliability

    DEFF Research Database (Denmark)

    Sangwongwanich, Ariya; Yang, Yongheng; Sera, Dezso

    2017-01-01

    . However, oversizing the PV array will increase the loading of PV inverters, which may have undesired influence on the PV inverter lifetime and reliability. In that case, it may result in a negative impact on the overall PV energy cost, due to the increased maintenance for the PV inverters. This paper...... evaluates the lifetime of PV inverters considering the PV array sizing and installation sites, e.g., Denmark and Arizona. The results reveal that the PV array sizing has a considerable impact on the PV inverter lifetime and reliability, especially in Denmark, where the average solar irradiance level...

  4. Impacts of PV Array Sizing on PV Inverter Lifetime and Reliability

    OpenAIRE

    Sangwongwanich, Ariya; Yang, Yongheng; Sera, Dezso; Blaabjerg, Frede

    2017-01-01

    In order to enable a more wide-scale utilization of PV systems, the cost of PV energy has to be comparable with other energy sources. Oversizing the PV array is one common approach to reduce the cost of PV energy, since it increases the PV energy yield during low solar irradiance conditions. However, oversizing the PV array will increase the loading of PV inverters, which may have undesired influence on the PV inverter lifetime and reliability. In that case, it may result in a negative impact...

  5. Redox proteomics of tomato in response to Pseudomonas syringae infection

    Science.gov (United States)

    Balmant, Kelly Mayrink; Parker, Jennifer; Yoo, Mi-Jeong; Zhu, Ning; Dufresne, Craig; Chen, Sixue

    2015-01-01

    Unlike mammals with adaptive immunity, plants rely on their innate immunity based on pattern-triggered immunity (PTI) and effector-triggered immunity (ETI) for pathogen defense. Reactive oxygen species, known to play crucial roles in PTI and ETI, can perturb cellular redox homeostasis and lead to changes of redox-sensitive proteins through modification of cysteine sulfhydryl groups. Although redox regulation of protein functions has emerged as an important mechanism in several biological processes, little is known about redox proteins and how they function in PTI and ETI. In this study, cysTMT proteomics technology was used to identify similarities and differences of protein redox modifications in tomato resistant (PtoR) and susceptible (prf3) genotypes in response to Pseudomonas syringae pv tomato (Pst) infection. In addition, the results of the redox changes were compared and corrected with the protein level changes. A total of 90 potential redox-regulated proteins were identified with functions in carbohydrate and energy metabolism, biosynthesis of cysteine, sucrose and brassinosteroid, cell wall biogenesis, polysaccharide/starch biosynthesis, cuticle development, lipid metabolism, proteolysis, tricarboxylic acid cycle, protein targeting to vacuole, and oxidation–reduction. This inventory of previously unknown protein redox switches in tomato pathogen defense lays a foundation for future research toward understanding the biological significance of protein redox modifications in plant defense responses. PMID:26504582

  6. Linkage mapping of candidate genes for induce resistance and growth promotion by trichoderma koningiopsis (th003) in tomato solanum lycopersicum

    International Nuclear Information System (INIS)

    Simbaqueba, Jaime; Cotes, Alba Marina; Barrero, Luz Stella

    2011-01-01

    Induced systemic resistance (ISR) is a mechanism by which plants enhance defenses against any stress condition. ISR and growth promotion are enhanced when tomato (Solanum lycopersicum) is inoculated with several strains of Trichoderma ssp. this study aims to genetically map tomato candidate genes involved in ISR and growth promotion induced by the Colombian native isolate Trichoderma koningiopsis th003. Forty-nine candidate genes previously identified on tomato plants treated with th003 and T. hamatum T382 strains were evaluated for polymorphisms and 16 of them were integrated on the highly saturated genetic linkage map named TOMATO EXPEN 2000. The location of six unigenes was similar to the location of resistance gene analogs (RGAS), defense related ests and resistance QTLs previously reported, suggesting new possible candidates for these quantitative trait loci (QTL) regions. The candidate gene-markers may be used for future ISR or growth promotion assisted selection in tomato.

  7. pH Control Enables Simultaneous Enhancement of Nitrogen Retention and N2O Reduction in Shewanella loihica Strain PV-4

    Directory of Open Access Journals (Sweden)

    Hayeon Kim

    2017-09-01

    Full Text Available pH has been recognized as one of the key environmental parameters with significant impacts on the nitrogen cycle in the environment. In this study, the effects of pH on NO3–/NO2– fate and N2O emission were examined with Shewanella loihica strain PV-4, an organism with complete denitrification and respiratory ammonification pathways. Strain PV-4 was incubated at varying pH with lactate as the electron donor and NO3–/NO2– and N2O as the electron acceptors. When incubated with NO3– and N2O at pH 6.0, transient accumulation of N2O was observed and no significant NH4+ production was observed. At pH 7.0 and 8.0, strain PV-4 served as a N2O sink, as N2O concentration decreased consistently without accumulation. Respiratory ammonification was upregulated in the experiments performed at these higher pH values. When NO2– was used in place of NO3–, neither growth nor NO2– reduction was observed at pH 6.0. NH4+ was the exclusive product from NO2– reduction at both pH 7.0 and 8.0 and neither production nor consumption of N2O was observed, suggesting that NO2– regulation superseded pH effects on the nitrogen-oxide dissimilation reactions. When NO3– was the electron acceptor, nirK transcription was significantly upregulated upon cultivation at pH 6.0, while nrfA transcription was significantly upregulated at pH 8.0. The highest level of nosZ transcription was observed at pH 6.0 and the lowest at pH 8.0. With NO2– as the electron acceptor, transcription profiles of nirK, nrfA, and nosZ were statistically indistinguishable between pH 7.0 and 8.0. The transcriptions of nirK and nosZ were severely downregulated regardless of pH. These observations suggested that the kinetic imbalance between N2O production and consumption, but neither decrease in expression nor activity of NosZ, was the major cause of N2O accumulation at pH 6.0. The findings also suggest that simultaneous enhancement of nitrogen retention and N2O emission reduction may be

  8. Identification, characterization and antigenicity of the Plasmodium vivax rhoptry neck protein 1 (PvRON1

    Directory of Open Access Journals (Sweden)

    Patarroyo Manuel E

    2011-10-01

    Full Text Available Abstract Background Plasmodium vivax malaria remains a major health problem in tropical and sub-tropical regions worldwide. Several rhoptry proteins which are important for interaction with and/or invasion of red blood cells, such as PfRONs, Pf92, Pf38, Pf12 and Pf34, have been described during the last few years and are being considered as potential anti-malarial vaccine candidates. This study describes the identification and characterization of the P. vivax rhoptry neck protein 1 (PvRON1 and examine its antigenicity in natural P. vivax infections. Methods The PvRON1 encoding gene, which is homologous to that encoding the P. falciparum apical sushi protein (ASP according to the plasmoDB database, was selected as our study target. The pvron1 gene transcription was evaluated by RT-PCR using RNA obtained from the P. vivax VCG-1 strain. Two peptides derived from the deduced P. vivax Sal-I PvRON1 sequence were synthesized and inoculated in rabbits for obtaining anti-PvRON1 antibodies which were used to confirm the protein expression in VCG-1 strain schizonts along with its association with detergent-resistant microdomains (DRMs by Western blot, and its localization by immunofluorescence assays. The antigenicity of the PvRON1 protein was assessed using human sera from individuals previously exposed to P. vivax malaria by ELISA. Results In the P. vivax VCG-1 strain, RON1 is a 764 amino acid-long protein. In silico analysis has revealed that PvRON1 shares essential characteristics with different antigens involved in invasion, such as the presence of a secretory signal, a GPI-anchor sequence and a putative sushi domain. The PvRON1 protein is expressed in parasite's schizont stage, localized in rhoptry necks and it is associated with DRMs. Recombinant protein recognition by human sera indicates that this antigen can trigger an immune response during a natural infection with P. vivax. Conclusions This study shows the identification and characterization of

  9. PV potential and potential PV rent in European regions

    DEFF Research Database (Denmark)

    Hansen, Anders Chr.; Thorn, Paul

    2013-01-01

    The paper provides a GIS based model for assessing the potentials of photovoltaic electricity in Europe by NUTS 2 regions. The location specific energy potential per PV-­‐panel area is estimated based on observations of solar irradiation, conversion efficiency, levelised costs and the social value...... of PV-­‐electricity. Combined with the potential density of PV-­‐panel area based on land cover and environental restrictions, the PV energy potential and the potential PV ressource rent is calculated. These calculations enbable the model to estimate the regional patterns at NUTS 2 level...

  10. One-step Multiplex RT-PCR Method for Simultaneous Detection of Seed Transmissible Bacteria and Viruses in Pepper and Tomato Seeds

    Directory of Open Access Journals (Sweden)

    Kyusik Jeong

    2011-04-01

    Full Text Available The aim of this study was to develop specific and sensitive PCR-based procedures for simultaneous detection of economically important plant seed infection pathogenic bacteria and virus, Xanthomonns campestris pv. vesicatoria (Xcv, Clavibacter michiganensis subsp. michiganensis (Cmm, Erwinia carotovora subsp. carotovora (Ecc, Pepper mild mottle virus (PMMoV and Tobacco mild green mosaic virus (TMGMV in pepper and tomato seeds. Most of pepper and tomato bacterial and virus diseases are responsible for germination and growth obstruction. PCR with arbitral primers: selection of specific primers, performance of PCR with specific primers and determination of the threshold level for pathogens detection. To detect simultaneously the Xcv, Cmm, Ecc, PMMoV and TMGMV in pepper and tomato seeds, five pairs (Cmm-F/R, Ecc-F/R, Xcv-F/R, PMMoV-F/R, TMGMV-F/R of specific primer were synthesized by primer-blast program. The multiplex PCR for the five pathogens in pepper and tomato seeds could detect specially without interference among primers and/or cDNA of plant seeds and other plant pathogens. The PCR result for pathogen detection using 20 commercial pepper and 10 tomato seed samples, Ecc was detected from 4 pepper and 2 tomato seed samples, PMMoV was detected from 1 pepper seed sample, and PMMoV and TMGMV were simultaneously detected from 1 pepper seed sample.

  11. Phylogenetic analysis of Tomato spotted wilt virus (TSWV) NSs protein demonstrates the isolated emergence of resistance-breaking strains in pepper.

    Science.gov (United States)

    Almási, Asztéria; Csilléry, Gábor; Csömör, Zsófia; Nemes, Katalin; Palkovics, László; Salánki, Katalin; Tóbiás, István

    2015-02-01

    Resurgence of Tomato spotted wilt virus (TSWV) worldwide as well as in Hungary causing heavy economic losses directed the attention to the factors contributing to the outbreak of this serious epidemics. The introgression of Tsw resistance gene into various pepper cultivars seemed to solve TSWV control, but widely used resistant pepper cultivars bearing the same, unique resistance locus evoked the rapid emergence of resistance-breaking (RB) TSWV strains. In Hungary, the sporadic appearance of RB strains in pepper-producing region was first observed in 2010-2011, but in 2012 it was detected frequently. Previously, the non-structural protein (NSs) encoded by small RNA (S RNA) of TSWV was verified as the avirulence factor for Tsw resistance, therefore we analyzed the S RNA of the Hungarian RB and wild type (WT) isolates and compared to previously analyzed TSWV strains with RB properties from different geographical origins. Phylogenetic analysis demonstrated that the different RB strains had the closest relationship with the local WT isolates and there is no conserved mutation present in all the NSs genes of RB isolates from different geographical origins. According to these results, we concluded that the RB isolates evolved separately in geographic point of view, and also according to the RB mechanism.

  12. Tomato contact dermatitis

    DEFF Research Database (Denmark)

    Paulsen, Evy; Christensen, Lars P; Andersen, Klaus Ejner

    2012-01-01

    The tomato plant (Solanum lycopersicum) is an important crop worldwide. Whereas immediate-type reactions to tomato fruits are well known, contact dermatitis caused by tomatoes or tomato plants is rarely reported. The aims of this study were to present new data on contact sensitization to tomato...... plants and review the literature on contact dermatitis caused by both plants and fruits. An ether extract of tomato plants made as the original oleoresin plant extracts, was used in aimed patch testing, and between 2005 and 2011. 8 of 93 patients (9%) tested positive to the oleoresin extracts....... This prevalence is in accordance with the older literature that reports tomato plants as occasional sensitizers. The same applies to tomato fruits, which, in addition, may cause protein contact dermatitis. The allergens of the plant are unknown, but both heat-stable and heat-labile constituents seem...

  13. Quality perception of organically grown tomatoes (Lycopersicon esculentum Mill. in Vienna, Austria

    Directory of Open Access Journals (Sweden)

    PK Ng’ang’a

    2015-12-01

    Full Text Available Austria is one of the major organic tomato producing countries for local and export marketing. These tomatoes are produced in parts of Austria especially around Vienna where their production system has to meet stringent organic quality standards in both local and international markets. These quality standards may put considerable strain on farmers and are normally formulated without famers’ participation so may not be wholly representative of the farmers’ quality interpretation. The aim of this paper is therefore to determine the Austrian organic tomatoes growers’ perception and practice of quality and challenges. Qualitative semi-structured interviews were carried out among 28 organic tomatoes farmers in Vienna, Austria. Findings suggest that quality of organic tomatoes is mainly perceived in terms of both informal values (big fruit size, long shelf life, food security and amount of income received from tomato sales as well as formal norms (non- application of chemicals, human health, damage free, sweet taste, red colour, and juiciness. There were no gendered differences in quality perception among the growers. High costs of production inputs were identified as the main challenge to attaining quality in organic tomatoes. Following these findings, there is need for effective participation of growers in formulation of standards as well as subsidizing of production inputs by the government. The Austrian tomato growers as well as local and international retailers should work closely to increase the price received by the Austrian organic tomato growers so that it more adequately covers their production costs.

  14. Pathogenic and genetic diversity of Xanthomonas translucens pv. undulosa in North Dakota.

    Science.gov (United States)

    Adhikari, Tika B; Gurung, Suraj; Hansen, Jana M; Bonman, J Michael

    2012-04-01

    Bacterial leaf streak (BLS), caused by Xanthomonas translucens pv. undulosa, has become more prevalent recently in North Dakota and neighboring states. From five locations in North Dakota, 226 strains of X. translucens pv. undulosa were collected and evaluated for pathogenicity and then selected strains were inoculated on a set of 12 wheat cultivars and other cereal hosts. The genetic diversity of all strains was determined using repetitive sequence-based polymerase chain reaction (rep-PCR) and insertion sequence-based (IS)-PCR. Bacterial strains were pathogenic on wheat and barley but symptom severity was greatest on wheat. Strains varied greatly in aggressiveness, and wheat cultivars also showed differential responses to several strains. The 16S ribosomal DNA sequences of the strains were identical, and distinct from those of the other Xanthomonas pathovars. Combined rep-PCR and IS-PCR data produced 213 haplotypes. Similar haplotypes were detected in more than one location. Although diversity was greatest (≈92%) among individuals within a location, statistically significant (P ≤ 0.001 or 0.05) genetic differentiation among locations was estimated, indicating geographic differentiation between pathogen populations. The results of this study provide information on the pathogen diversity in North Dakota, which will be useful to better identify and characterize resistant germplasm.

  15. USE OF SAPROPHYTIC FUNGI SPECIMENS AS A PLANT PROTECTION AGENTS IN TOMATOE PLANTATION

    Directory of Open Access Journals (Sweden)

    Katarzyna Bandurska

    2015-07-01

    Full Text Available The purpose of this study was to determine the effects of the Trichoderma spp. fungi on the conditions and health of tomato plants. The experiments were conducted in pot cultures and controlled conditions. Commercial formula TRIFENDER containing Trichoderma asperellum spores and isolated from garden soil strain T12 Trichoderma viride were used. In one embodiment, the plants were treated with pathogenic strain of Fusarium sp. that commonly damages crops and against which the whole arsenal of chemicals is used. Preparations obtained from isolated and multiplied fungal cultures were used for the treatment of the above-ground (spraying and under-ground (sprinkling parts of tomatoes. Influence of the Trichoderma fungi was determined by comparing the presence of necrosis on leaves in various groups of cultivated tomatoes compared to control samples. The development of seedlings was checked by measuring the length of plants and the weight of fresh and dry plants. The results demonstrated the protective role of Trichoderma spp. fungi in relation to the Fusarium sp.. Leaves of tomato treated with solutions of saprophytic fungi had a statistically significant lower amount of necrotic changes caused by the pathogen. More effective in this regard was uncommercial isolate of T. viride. Formulation used in the experiments Trifender and isolate T. viride statistically significant influence on the growth and development of the tomato plants as evidenced by increased compared to the control fresh and dry weight of plants.

  16. The Arabidopsis lectin receptor kinase LecRK-V.5 represses stomatal immunity induced by Pseudomonas syringae pv. tomato DC3000.

    Directory of Open Access Journals (Sweden)

    Marie Desclos-Theveniau

    2012-02-01

    Full Text Available Stomata play an important role in plant innate immunity by limiting pathogen entry into leaves but molecular mechanisms regulating stomatal closure upon pathogen perception are not well understood. Here we show that the Arabidopsis thaliana L-type lectin receptor kinase-V.5 (LecRK-V.5 negatively regulates stomatal immunity. Loss of LecRK-V.5 function increased resistance to surface inoculation with virulent bacteria Pseudomonas syringae pv tomato DC3000. Levels of resistance were not affected after infiltration-inoculation, suggesting that LecRK-V.5 functions at an early defense stage. By contrast, lines overexpressing LecRK-V.5 were more susceptible to Pst DC3000. Enhanced resistance in lecrk-V.5 mutants was correlated with constitutive stomatal closure, while increased susceptibility phenotypes in overexpression lines were associated with early stomatal reopening. Lines overexpressing LecRK-V.5 also demonstrated a defective stomatal closure after pathogen-associated molecular pattern (PAMP treatments. LecRK-V.5 is rapidly expressed in stomatal guard cells after bacterial inoculation or treatment with the bacterial PAMP flagellin. In addition, lecrk-V.5 mutants guard cells exhibited constitutive accumulation of reactive oxygen species (ROS and inhibition of ROS production opened stomata of lecrk-V.5. LecRK-V.5 is also shown to interfere with abscisic acid-mediated stomatal closure signaling upstream of ROS production. These results provide genetic evidences that LecRK-V.5 negatively regulates stomatal immunity upstream of ROS biosynthesis. Our data reveal that plants have evolved mechanisms to reverse bacteria-mediated stomatal closure to prevent long-term effect on CO(2 uptake and photosynthesis.

  17. Detection and molecular characterization of tomato yellow leaf curl virus naturally infecting Lycopersicon esculentum in Egypt.

    Science.gov (United States)

    Rabie, M; Ratti, C; Abdel Aleem, E; Fattouh, F

    Tomato yellow leaf curl virus (TYLCV) infections of tomato crops in Egypt were widely spread in 2014. Infected symptomatic tomato plants from different governorates were sampled. TYLCV strains Israel and Mild (TYLCV-IL, TYLCV-Mild) were identified by multiplex and real-time PCR. In addition, nucleotide sequence analysis of the V1 and V2 protein genes, revealed ten TYLCV Egyptian isolates (TYLCV from TY1 to 10). Phylogenetic analysis showed their high degree of relatedness with TYLCV-IL Jordan isolate (98%). Here we have showed the complete nucleotide sequence of the TYLCV Egyptian isolate TY10, sampled from El Beheira. A high degree of similarity to other previously reported Egyptian isolates and isolates from Jordan and Japan reflect the importance of phylogenetic analysis in monitoring virus genetic diversity and possibilities for divergence of more virulent strains or genotypes.

  18. Self-protection of Pseudomonas syringae pv. tabaci from its toxin, tabtoxinine-β-lactam

    International Nuclear Information System (INIS)

    Knight, T.J.; Durbin, R.D.; Langston-Unkefer, P.J.

    1987-01-01

    An extracellular toxin, tabtoxinine-β-lactam (TβL), is produced by Pseudomonas syringae pv. tabaci. This toxin irreversibly inhibits its target, glutamine synthetase; yet P. syringae pv. tabaci retains significant amounts of glutamine synthetase activity during toxin production in culture. As part of our investigation of the self-protection of P. syringae pv. tabaci, the authors compared the effects of TβL on Tox + (TβL-producing, insensitive to TβL) and Tox - (TβL nonproducing, sensitive to TΛ) strains. The extent of protection afforded to the Tox - strain when induced to adenylylate glutamine synthetase was tested. It was concluded that an additional protection mechanism was required. A detoxification activity was found in the Tox + strain which opens the ε-lactam ring to TβL to produce the inactive, open-chain form, tabtoxinine. Whole cells of the Tox + strain incubated for 24 h with [ 14 C]TβL (0.276 μmol/3 x 10 10 cells) contained [ 14 C]tabtoxinine (0.056 μmol), and the medium contained TβL (0.226 μmol). Extracts of spheroplasts of the Tox + stain also converted TβL to tabtoxinine, whereas extracts of the Tox - strain did not alter TβL. The conversion was time dependent and stoichiometric and was destroyed by boiling for 30 min or by the addition of 5mM EDTA. Penicillin, a possible substrate and competitive inhibitor of this lactamase activity, inhibited the conversion of TΛ to tabtoxinine. Periplasmic fluid did not catalyze the conversion of TβL

  19. Biofilm formation is determinant in tomato rhizosphere colonization by Bacillus velezensis FZB42.

    Science.gov (United States)

    Al-Ali, Ameen; Deravel, Jovana; Krier, François; Béchet, Max; Ongena, Marc; Jacques, Philippe

    2017-10-23

    In this work, the behavior in tomato rhizosphere of Bacillus velezensis FZB42 was analyzed taking into account the surfactin production, the use of tomato roots exudate as substrates, and the biofilm formation. B. velezensis FZB42 and B. amyloliquefaciens S499 have a similar capability to colonize tomato rhizosphere. Little difference in this colonization was observed with surfactin non producing B. velezensis FZB42 mutant strains. B. velezensis is able to grow in the presence of root exudate and used preferentially sucrose, maltose, glutamic, and malic acids as carbon sources. A mutant enable to produce exopolysaccharide (EPS - ) was constructed to demonstrate the main importance of biofilm formation on rhizosphere colonization. This mutant had completely lost its ability to form biofilm whatever the substrate present in the culture medium and was unable to efficiently colonize tomato rhizosphere.

  20. Interband cascade (IC) photovoltaic (PV) architecture for PV devices

    Science.gov (United States)

    Yang, Rui Q.; Tian, Zhaobing; Mishima, Tetsuya D.; Santos, Michael B.; Johnson, Matthew B.; Klem, John F.

    2015-10-20

    A photovoltaic (PV) device, comprising a PV interband cascade (IC) stage, wherein the IC PV stage comprises an absorption region with a band gap, the absorption region configured to absorb photons, an intraband transport region configured to act as a hole barrier, and an interband tunneling region configured to act as an electron barrier. An IC PV architecture for a photovoltaic device, the IC PV architecture comprising an absorption region, an intraband transport region coupled to the absorption region, and an interband tunneling region coupled to the intraband transport region and to the adjacent absorption region, wherein the absorption region, the intraband transport region, and the interband tunneling region are positioned such that electrons will flow from the absorption region to the intraband transport region to the interband tunneling region.

  1. Association and Expression of Virulence from Plasmids of the Group B Strain in Pseudomonas syringae pv. eriobotryae

    Directory of Open Access Journals (Sweden)

    Tran Dang Khanh

    2018-04-01

    Full Text Available Pseudomonas syringae pv. eriobotryae causes serious stem canker in loquat (Eriobotrya japonica trees. This study was conducted to determine whether plasmids are involved with its virulence. The strain NAE89, which belonged to the B group, harbored two plasmids at approximately 6.2 and 50 Mdal that caused stem canker and halo leaf spots on loquat plants. Following digestion with BamHI and ligation into the BamHI cloning site of the broad range host cosmid pLAFR3, four DNA fragments at 3.8, 6.6, 12.3, and 22.8 kb were generated. Although the plasmid-encoded virulence gene psvA was undigested with the BamHI, the halo leaf spot gene may be adjacent to the psvA gene was digested. A pLAFR3 cosmid clone was introduced into the non-pathogenic PE0 and NAE89-1 strains by triparental matings and the pathogenicity was recovered. As a result, the pLAFR3 cosmid clone was introduced into the largest size DNA fragment of 22.8 kb and determined to be the causal agent of canker on the stem of the loquat. This study revealed that the psvA gene, previously found in the 50 Mdal plasmid, was also observed in the 22.8 kb DNA fragment.

  2. An Analysis of Open World PvP in LOTRO's PvMP as a Case Study for PvP Games

    Directory of Open Access Journals (Sweden)

    Toh Weimin

    2014-11-01

    Full Text Available This article focuses on the analysis of emergent gameplay, based on a case study of the author's subjective gameplay experience of Player versus Monster Player (PvMP in The Lord of the Rings Online (LOTRO. The argument presented here is that although there is a core system of Player versus Player (PvP which LOTRO shares with other online games, each type of online game has a specific kind of PvP system which attracts players to engage in the gameplay. For instance, the open world sandbox type of PvP attracts certain players to play in LOTRO's PvMP. One of the main aims of this study is thus to investigate some of the core systems of PvP gameplay in open world sandbox PvP. In this article, LOTRO is shown to offer unique opportunities for studying emergent gameplay in open world games, with particular relevance to PvP studies. Two of the core systems of PvP discussed include the design of the simple gameplay rules to support emergent gameplay, and the community's attitudes towards player's behaviours. The types of emergent gameplay discussed include free play versus negotiated fair play, the players' utilisation of strategies in open world PvP to support collaborative and competitive gameplay, and the changing dynamics of open ended gameplay. It is hoped that the analysis provided in this article would form the­ basis of future work on a more general framework for understanding PvP in other online games.

  3. Fire resistant PV shingle assembly

    Science.gov (United States)

    Lenox, Carl J.

    2012-10-02

    A fire resistant PV shingle assembly includes a PV assembly, including PV body, a fire shield and a connection member connecting the fire shield below the PV body, and a support and inter-engagement assembly. The support and inter-engagement assembly is mounted to the PV assembly and comprises a vertical support element, supporting the PV assembly above a support surface, an upper interlock element, positioned towards the upper PV edge, and a lower interlock element, positioned towards the lower PV edge. The upper interlock element of one PV shingle assembly is inter-engageable with the lower interlock element of an adjacent PV shingle assembly. In some embodiments the PV shingle assembly may comprise a ventilation path below the PV body. The PV body may be slidably mounted to the connection member to facilitate removal of the PV body.

  4. PV/T slates - Laboratory measurements; PV/T-Schiefer. Labormessungen

    Energy Technology Data Exchange (ETDEWEB)

    Kropf, S.

    2003-07-01

    This comprehensive, illustrated report for the Swiss Federal Office of Energy (SFOE) is one a series of five reports dealing with increasing the overall efficiency of photovoltaic (PV) installations by also using the heat collected by the dark-coloured PV panels. The work reported on addresses open questions on the use of the heat and its optimal use. This report deals with an experimental outdoor set-up and reviews in-situ measurements made on a prototype of a ventilated PV-tile system (PV/T-Slates). The report describes the configuration and construction of the experimental PV-tiled roof and the measurement system used to measure its electrical and thermal performance. The results of the measurements made are presented in detail in graphical form. The influence of various factors such as air-slit width and mounting angle are discussed.

  5. Plasmodium vivax Tryptophan Rich Antigen PvTRAg36.6 Interacts with PvETRAMP and PvTRAg56.6 Interacts with PvMSP7 during Erythrocytic Stages of the Parasite.

    Directory of Open Access Journals (Sweden)

    Kriti Tyagi

    Full Text Available Plasmodium vivax is most wide spread and a neglected malaria parasite. There is a lack of information on parasite biology of this species. Genome of this parasite encodes for the largest number of tryptophan-rich proteins belonging to 'Pv-fam-a' family and some of them are potential drug/vaccine targets but their functional role(s largely remains unexplored. Using bacterial and yeast two hybrid systems, we have identified the interacting partners for two of the P. vivax tryptophan-rich antigens called PvTRAg36.6 and PvTRAg56.2. The PvTRAg36.6 interacts with early transcribed membrane protein (ETRAMP of P.vivax. It is apically localized in merozoites but in early stages it is seen in parasite periphery suggesting its likely involvement in parasitophorous vacuole membrane (PVM development or maintenance. On the other hand, PvTRAg56.2 interacts with P.vivax merozoite surface protein7 (PvMSP7 and is localized on merozoite surface. Co-localization of PvTRAg56.2 with PvMSP1 and its molecular interaction with PvMSP7 probably suggest that, PvTRAg56.2 is part of MSP-complex, and might assist or stabilize the protein complex at the merozoite surface. In conclusion, the PvTRAg proteins have different sub cellular localizations and specific associated functions during intra-erythrocytic developmental cycle.

  6. Plasmodium vivax Tryptophan Rich Antigen PvTRAg36.6 Interacts with PvETRAMP and PvTRAg56.6 Interacts with PvMSP7 during Erythrocytic Stages of the Parasite

    Science.gov (United States)

    Tyagi, Kriti; Hossain, Mohammad Enayet; Thakur, Vandana; Aggarwal, Praveen; Malhotra, Pawan; Mohmmed, Asif; Sharma, Yagya Dutta

    2016-01-01

    Plasmodium vivax is most wide spread and a neglected malaria parasite. There is a lack of information on parasite biology of this species. Genome of this parasite encodes for the largest number of tryptophan-rich proteins belonging to ‘Pv-fam-a’ family and some of them are potential drug/vaccine targets but their functional role(s) largely remains unexplored. Using bacterial and yeast two hybrid systems, we have identified the interacting partners for two of the P. vivax tryptophan-rich antigens called PvTRAg36.6 and PvTRAg56.2. The PvTRAg36.6 interacts with early transcribed membrane protein (ETRAMP) of P.vivax. It is apically localized in merozoites but in early stages it is seen in parasite periphery suggesting its likely involvement in parasitophorous vacuole membrane (PVM) development or maintenance. On the other hand, PvTRAg56.2 interacts with P.vivax merozoite surface protein7 (PvMSP7) and is localized on merozoite surface. Co-localization of PvTRAg56.2 with PvMSP1 and its molecular interaction with PvMSP7 probably suggest that, PvTRAg56.2 is part of MSP-complex, and might assist or stabilize the protein complex at the merozoite surface. In conclusion, the PvTRAg proteins have different sub cellular localizations and specific associated functions during intra-erythrocytic developmental cycle. PMID:26954579

  7. Induced resistance in tomato by SAR activators during predisposing salinity stress

    Directory of Open Access Journals (Sweden)

    Matthew Francis Pye

    2013-05-01

    Full Text Available Plant activators are chemicals that induce disease resistance. The phytohormone salicylic acid (SA is a crucial signal for systemic acquired resistance (SAR, and SA-mediated resistance is a target of several commercial plant activators, including Actigard (1,2,3-benzothiadiazole-7-thiocarboxylic acid-s-methyl-ester, BTH and Tiadinil (N-(3-chloro-4-methylphenyl-4-methyl-1,2,3-thiadiazole-5-carboxamide, TDL. BTH and TDL were examined for their impact on abscisic acid (ABA-mediated, salt-induced disease predisposition in tomato seedlings. A brief episode of salt stress to roots significantly increased the severity of disease caused by Pseudomonas syringae pv. tomato (Pst and Phytophthora capsici relative to non-stressed plants. Root treatment with TDL induced resistance to Pst in leaves and provided protection in both non-stressed and salt-stressed seedlings in WT and highly susceptible NahG plants. Non-stressed and salt-stressed ABA-deficient sitiens mutants were highly resistant to Pst. Neither TDL nor BTH induced resistance to root infection by P. capsici, nor did they moderate the salt-induced increment in disease severity. Root treatment with these plant activators increased the levels of ABA in roots and shoots similar to levels observed in salt-stressed plants. The results indicate that SAR activators can protect tomato plants from bacterial speck disease under predisposing salt stress, and suggest that some SA-mediated defense responses function sufficiently in plants with elevated levels of ABA.

  8. A Novel Protein Elicitor BAR11 From Saccharothrix yanglingensis Hhs.015 Improves Plant Resistance to Pathogens and Interacts With Catalases as Targets

    OpenAIRE

    Yanan Zhang; Yanan Zhang; Xia Yan; Xia Yan; Hongmei Guo; Hongmei Guo; Feiyang Zhao; Feiyang Zhao; Lili Huang; Lili Huang

    2018-01-01

    Previously, we reported the biocontrol effects of Saccharothrix yanglingensis strain Hhs.015 on Valsa mali. Here, we report a novel protein elicitor BAR11 from the biocontrol strain Hhs.015 and its functions in plant defense responses. Functional analysis showed that the elicitor BAR11 significantly stimulated plant systemic resistance in Arabidopsis thaliana to Pseudomonas syringae pv. tomato DC3000. In addition, systemic tissues accumulated reactive oxygen species and deposited callose in a...

  9. Transgenic tomato plants overexpressing tyramine N-hydroxycinnamoyltransferase exhibit elevated hydroxycinnamic acid amide levels and enhanced resistance to Pseudomonas syringae.

    Science.gov (United States)

    Campos, Laura; Lisón, Purificación; López-Gresa, María Pilar; Rodrigo, Ismael; Zacarés, Laura; Conejero, Vicente; Bellés, José María

    2014-10-01

    Hydroxycinnamic acid amides (HCAA) are secondary metabolites involved in plant development and defense that have been widely reported throughout the plant kingdom. These phenolics show antioxidant, antiviral, antibacterial, and antifungal activities. Hydroxycinnamoyl-CoA:tyramine N-hydroxycinnamoyl transferase (THT) is the key enzyme in HCAA synthesis and is induced in response to pathogen infection, wounding, or elicitor treatments, preceding HCAA accumulation. We have engineered transgenic tomato plants overexpressing tomato THT. These plants displayed an enhanced THT gene expression in leaves as compared with wild type (WT) plants. Consequently, leaves of THT-overexpressing plants showed a higher constitutive accumulation of the amide coumaroyltyramine (CT). Similar results were found in flowers and fruits. Moreover, feruloyltyramine (FT) also accumulated in these tissues, being present at higher levels in transgenic plants. Accumulation of CT, FT and octopamine, and noradrenaline HCAA in response to Pseudomonas syringae pv. tomato infection was higher in transgenic plants than in the WT plants. Transgenic plants showed an enhanced resistance to the bacterial infection. In addition, this HCAA accumulation was accompanied by an increase in salicylic acid levels and pathogenesis-related gene induction. Taken together, these results suggest that HCAA may play an important role in the defense of tomato plants against P. syringae infection.

  10. The PV market

    International Nuclear Information System (INIS)

    Hammond, B.

    1992-01-01

    This paper forecasts the photovoltaic (PV) market growth for the 1990s. Ten years of PV history are reviewed and used to establish market trends in terms of average selling price (ASP) and kilowatts shipped by market segment. The market is segmented into indoor consumer, stand-alone, and grid-connected applications. Indoor consumer presently represents a saturated market and is fairly predictable. The stand-alone market (i.e. not connected to the utility grid) is fairly stable and predictable. The utility PV market however is highly dependent on a number of market factors such as the cost of conventional energy the cost of PV systems utility acceptance of PV and regulatory controls. Government and institutional regulations, environmental issues, and OPEC and Middle East politics will have the greatest impact on the cost of conventional fuels. Private and federal investment in PV technology development could have a significant impact on the cost of PV systems. Forecasts are provided through the year 2000 for indoor consumer stand-alone and utility markets

  11. Philadelphia and the Tomato.

    Science.gov (United States)

    Smith, Andrew F.; Kling, Tatiana

    This booklet describes for elementary students the many contributions of people, traveling many places, over many years to bring the tomato to Philadelphia. The booklet includes the following: (1) "Introduction to the Tomato"; (2) "Where Does the Tomato Come From?"; (3) "The Spanish Tomato"; (4) "The Philadelphia…

  12. Bacillus effect on the germination and growth of tomato seedlings (Solanum lycopersicum L.

    Directory of Open Access Journals (Sweden)

    Teresa Cabra Cendales

    2017-01-01

    Full Text Available The capacity to solubilize phosphate and to produce indole compounds Indole Acetic Acid type, was evaluated in 15 strains isolated from castor bean lignocellulosic residues (Ricinus communis. To determine the solubilizing activity of phosphates a qualitative test by using Pikovskaya culture medium was employed and for the evaluation of the production of indole compounds (IAA a Salkowsky colorimetric analysis technique was applied. Among the microorganisms tested, the Bacillus pumilus GIBI 206 demonstrated capacity to solubilize phosphates and Bacillus subtilis GIBI 200 showed of capacity to solubilize phosphates and to produce Indoleacetic Acid (IAA. To determine the effect of the Bacillus subtilis strain on germination and growth promotion, tomato seeds (Solanum lycopersicum ‘Santa Clara’ were inoculated; the inoculation of the seeds along with the microorganism revealed statistically significant differences, during the germination stage compared to the control treatment. Nevertheless, it revealed a positive influence on the development of tomato plants, originating a significant increase on the mass and length of its stem and root. The results of this research offer the possibility of using the Bacillus subtilis as a growth promoter in tomato seedlings and in the formulation of bio-products.

  13. Fungitoxic potential of tagetes erectus for the management of alternaria alternata strains of tomato

    International Nuclear Information System (INIS)

    Mehmood, T.; Shafique, S.; Shafique, S.; Zaheer, Z.

    2014-01-01

    Tomato (Lycopersicum esculentum Mill.) is economically the most vital vegetable crops of this world but diseases reduce tomato production to a greater extent worldwide. Plants exudates contribute a lot in fight against pathogens. The current study indicates the pathogenic potential of Alternaria alternata FCBP-573 against tomato. RAPD analysis confirmed that A. alternata FCBP-573 had variability in its genetic constitution with other two isolates; this disparity in genetic constitution might be a cause to stir up more pathogenicity in this isolate. Therefore, it was selected as the most pathogenic isolate and subjected to biological control through Tagetes erectus L. In antifungal bioassays different plant parts of T. erectus with 1-4% concentrations of aqueous, and organic extracts of each part were evaluated against A. alternata FCBP- 573. Results revealed that the growth of A. alternata FCBP-573 was greatly inhibited at 4% concentration of methanol extract followed by aqueous and n-hexane extract. Among different plant parts tested, root extract exhibited more promising results by causing 81-92% reduction in biomass. The research concludes that aqueous and organic extracts of ornamentals have potential to obstruct dreadful effect of pathogenic fungi by suppressing their growth. T. erectus conferred vital and surprisingly stable compounds having inhibitory potential against A. alternata FCBP-573. (author)

  14. Phenylacetic acid-producing Rhizoctonia solani represses the biosynthesis of nematicidal compounds in vitro and influences biocontrol of Meloidogyne incognita in tomato by Pseudomonas fluorescens strain CHA0 and its GM derivatives.

    Science.gov (United States)

    Siddiqui, I A; Shaukat, S S

    2005-01-01

    The aim of the present investigation was to determine the influence of Rhizoctonia solani and its pathogenicity factor on the production of nematicidal agent(s) by Pseudomonas fluorescens strain CHA0 and its GM derivatives in vitro and nematode biocontrol potential by bacterial inoculants in tomato. One (Rs7) of the nine R. solani isolates from infected tomato roots inhibited seedling emergence and caused root rot in tomato. Thin layer chromatography revealed that culture filtrates of two isolates (Rs3 and Rs7) produced brown spots at Rf-values closely similar to synthetic phenylacetic acid (PAA), a phytotoxic factor. Filtrates from isolate Rs7, amended with the growth medium of P. fluorescens, markedly repressed nematicidal activity and PhlA'-'LacZ reporter gene expression of the bacteria in vitro. On the contrary, isolate Rs4 enhanced nematicidal potential of a 2,4-diacetylphloroglucinol overproducing mutant, CHA0/pME3424, of P. fluorescens strain CHA0 in vitro. Therefore, R. solani isolates Rs4 and Rs7 were tested more rigorously for their potential to influence biocontrol effectiveness of the bacterial agents. Methanol extract of the culture filtrates of PAA-producing isolate Rs7 resulting from medium amended with phenylalanine enhanced fungal repression of the production of nematicidal agents by bacteria, while amendments with zinc or molybdenum eliminated such fungal repression, thereby restoring bacterial potential to cause nematode mortality in vitro. A pot experiment was carried out, 3-week-old tomato seedlings were infested with R. solani isolates Rs4 or Rs7 and/or inoculated with Meloidogyne incognita, the root-knot nematode. The infested soil was treated with aqueous cell suspensions (10(8) CFU) of P. fluorescens strain CHA0 or its GM derivatives or left untreated (as a control). Observations taken 45 days after nematode inoculation revealed that, irrespective of the bacterial treatments, galling intensity per gram of fresh tomato roots was markedly

  15. COMPARISON OF CAROTENOID CONTENT IN TOMATO, TOMATO PULP AND KETCHUP BY LIQUID CHROMATOGRAPHY

    Directory of Open Access Journals (Sweden)

    J. J. T. GAMA

    2009-01-01

    Full Text Available

    Although tomatoes are commonly consumed fresh, over 80 % the consumption of tomatoes is in the form of processed products such as tomato pulp, ketchup, juice and sauce. Research has indicated the potential health benefits of a diet rich in tomatoes and tomato products. The present study was carried out to determine the carotenoid content of fresh tomato, tomato pulp and ketchup by high performance liquid chromatography. The major differences among these products were in the concentration of some of the pigments. Tomato had all-trans-lycopene (1046-1099 μg/g DW, cislycopene (125-132 μg/g DW and all-trans- -carotene (45-59 μg/g DW as principal carotenoids. Tomato pulp and ketchup had all-trans-lycopene (951-999 μg/g DW and 455-476 μg/g DW, all-trans- -carotene (76-88 DW μg/g and 20-27 DW μg/g and cis-lycopene (71-83 μg/g DW and 14-25 μg/g DW as the main pigments, respectively. They also contained other carotenoids in much smaller amounts (lycoxanthin, zeaxanthin, anteraxanthin, lutein, -carotene, -carotene and phytofluene.

  16. Effect of gamma-irradiation on the survival of Listeria monocytogenes and allergenicity of cherry tomatoes

    International Nuclear Information System (INIS)

    Todoriki, Setsuko; Bari, Latiful; Kitta, Kazumi; Ohba, Mika; Ito, Yasuhiro; Tsujimoto, Yuka; Kanamori, Norihito; Yano, Erika; Moriyama, Tatsuya; Kawamura, Yukio; Kawamoto, Shinichi

    2009-01-01

    The presence of Listeria monocytogenes in fresh produce is a growing concern because of the possibility of food-borne illness. Ionizing radiation is an effective non-thermal means of eliminating pathogenic bacteria in fresh produce; however, the effect of ionizing irradiation on the allergenic properties of the host commodities remains unknown. This study aimed (i) to determine the effective dose of gamma-irradiation in eliminating L. monocytogenes on whole cherry tomatoes and (ii) to evaluate the effect of gamma-irradiation on the allergenic properties of tomato proteins. Cherry tomatoes that were inoculated with a mixture of five L. monocytogenes strains were treated with gamma-rays from a 60 Co source. A 1.25 kGy dose of gamma-irradiation was found to be sufficient to eliminate L. monocytogenes on whole cherry tomatoes. The immunoblot profile of serum samples obtained from two patients with tomato allergy revealed that gamma-irradiation did not affect the allergenicity of tomato proteins for up to 7 days after irradiation when the tomatoes were stored at 20 deg. C. Additionally, the m-RNA levels of β-fructofuranosidase, polygalacturonase, pectin esterase, and superoxide dismutase, the main allergenic proteins in tomato, were not affected by the applied irradiation dose. Thus, this study demonstrated that a 1.25 kGy dose of gamma-irradiation effectively eliminates L. monocytogenes on cherry tomatoes without affecting the expression of allergenic proteins in the fruits.

  17. Effect of gamma-irradiation on the survival of Listeria monocytogenes and allergenicity of cherry tomatoes

    Science.gov (United States)

    Todoriki, Setsuko; Bari, Latiful; Kitta, Kazumi; Ohba, Mika; Ito, Yasuhiro; Tsujimoto, Yuka; Kanamori, Norihito; Yano, Erika; Moriyama, Tatsuya; Kawamura, Yukio; Kawamoto, Shinichi

    2009-07-01

    The presence of Listeria monocytogenes in fresh produce is a growing concern because of the possibility of food-borne illness. Ionizing radiation is an effective non-thermal means of eliminating pathogenic bacteria in fresh produce; however, the effect of ionizing irradiation on the allergenic properties of the host commodities remains unknown. This study aimed (i) to determine the effective dose of gamma-irradiation in eliminating L. monocytogenes on whole cherry tomatoes and (ii) to evaluate the effect of gamma-irradiation on the allergenic properties of tomato proteins. Cherry tomatoes that were inoculated with a mixture of five L. monocytogenes strains were treated with gamma-rays from a 60Co source. A 1.25 kGy dose of gamma-irradiation was found to be sufficient to eliminate L. monocytogenes on whole cherry tomatoes. The immunoblot profile of serum samples obtained from two patients with tomato allergy revealed that gamma-irradiation did not affect the allergenicity of tomato proteins for up to 7 days after irradiation when the tomatoes were stored at 20 °C. Additionally, the m-RNA levels of β-fructofuranosidase, polygalacturonase, pectin esterase, and superoxide dismutase, the main allergenic proteins in tomato, were not affected by the applied irradiation dose. Thus, this study demonstrated that a 1.25 kGy dose of gamma-irradiation effectively eliminates L. monocytogenes on cherry tomatoes without affecting the expression of allergenic proteins in the fruits.

  18. Effect of gamma-irradiation on the survival of Listeria monocytogenes and allergenicity of cherry tomatoes

    Energy Technology Data Exchange (ETDEWEB)

    Todoriki, Setsuko [National Food Research Institute, Tsukuba, Ibaraki 305-8642 (Japan)], E-mail: setsuko@affrc.go.jp; Bari, Latiful; Kitta, Kazumi; Ohba, Mika; Ito, Yasuhiro; Tsujimoto, Yuka [National Food Research Institute, Tsukuba, Ibaraki 305-8642 (Japan); Kanamori, Norihito [Japan International Research Center for Agricultural Science, Tsukuba, Ibaraki 305-8686 (Japan); Yano, Erika; Moriyama, Tatsuya; Kawamura, Yukio [School of Agriculture, Kinki University, Nara-city, Nara 631-8505 (Japan); Kawamoto, Shinichi [National Food Research Institute, Tsukuba, Ibaraki 305-8642 (Japan)

    2009-07-15

    The presence of Listeria monocytogenes in fresh produce is a growing concern because of the possibility of food-borne illness. Ionizing radiation is an effective non-thermal means of eliminating pathogenic bacteria in fresh produce; however, the effect of ionizing irradiation on the allergenic properties of the host commodities remains unknown. This study aimed (i) to determine the effective dose of gamma-irradiation in eliminating L. monocytogenes on whole cherry tomatoes and (ii) to evaluate the effect of gamma-irradiation on the allergenic properties of tomato proteins. Cherry tomatoes that were inoculated with a mixture of five L. monocytogenes strains were treated with gamma-rays from a {sup 60}Co source. A 1.25 kGy dose of gamma-irradiation was found to be sufficient to eliminate L. monocytogenes on whole cherry tomatoes. The immunoblot profile of serum samples obtained from two patients with tomato allergy revealed that gamma-irradiation did not affect the allergenicity of tomato proteins for up to 7 days after irradiation when the tomatoes were stored at 20 deg. C. Additionally, the m-RNA levels of {beta}-fructofuranosidase, polygalacturonase, pectin esterase, and superoxide dismutase, the main allergenic proteins in tomato, were not affected by the applied irradiation dose. Thus, this study demonstrated that a 1.25 kGy dose of gamma-irradiation effectively eliminates L. monocytogenes on cherry tomatoes without affecting the expression of allergenic proteins in the fruits.

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

    Science.gov (United States)

    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.

  20. Gaseous 3-pentanol primes plant immunity against a bacterial speck pathogen, Pseudomonas syringae pv. tomato via salicylic acid and jasmonic acid-dependent signaling pathways in Arabidopsis.

    Science.gov (United States)

    Song, Geun C; Choi, Hye K; Ryu, Choong-Min

    2015-01-01

    3-Pentanol is an active organic compound produced by plants and is a component of emitted insect sex pheromones. A previous study reported that drench application of 3-pentanol elicited plant immunity against microbial pathogens and an insect pest in crop plants. Here, we evaluated whether 3-pentanol and the derivatives 1-pentanol and 2-pentanol induced plant systemic resistance using the in vitro I-plate system. Exposure of Arabidopsis seedlings to 10 μM and 100 nM 3-pentanol evaporate elicited an immune response to Pseudomonas syringae pv. tomato DC3000. We performed quantitative real-time PCR to investigate the 3-pentanol-mediated Arabidopsis immune responses by determining Pathogenesis-Related (PR) gene expression levels associated with defense signaling through salicylic acid (SA), jasmonic acid (JA), and ethylene signaling pathways. The results show that exposure to 3-pentanol and subsequent pathogen challenge upregulated PDF1.2 and PR1 expression. Selected Arabidopsis mutants confirmed that the 3-pentanol-mediated immune response involved SA and JA signaling pathways and the NPR1 gene. Taken together, this study indicates that gaseous 3-pentanol triggers induced resistance in Arabidopsis by priming SA and JA signaling pathways. To our knowledge, this is the first report that a volatile compound of an insect sex pheromone triggers plant systemic resistance against a bacterial pathogen.

  1. Gaseous 3-pentanol primes plant immunity against a bacterial speck pathogen, Pseudomonas syringae pv. tomato via salicylic acid and jasmonic acid-dependent signaling pathways in Arabidopsis

    Directory of Open Access Journals (Sweden)

    Geun Cheol eSong

    2015-10-01

    Full Text Available 3-Pentanol is an active organic compound produced by plants and is a component of emitted insect sex pheromones. A previous study reported that drench application of 3-pentanol elicited plant immunity against microbial pathogens and an insect pest in crop plants. Here, we evaluated whether 3-pentanol and the derivatives 1-pentanol and 2-pentanol induced plant systemic resistance using the in vitro I-plate system. Exposure of Arabidopsis seedlings to 10 M and 100 nM 3-pentanol evaporate elicited an immune response to Pseudomonas syringae pv. tomato DC3000. We performed quantitative real-time PCR to investigate the 3-pentanol-mediated Arabidopsis immune responses by determining Pathogenesis-Related (PR gene expression levels associated with defense signaling through SA, JA, and ethylene signaling pathways. The results show that exposure to 3-pentanol and subsequent pathogen challenge upregulated PDF1.2 and PR1 expression. Selected Arabidopsis mutants confirmed that the 3-pentanol-mediated immune response involved salicylic acid (SA and jasmonic acid (JA signaling pathways and the NPR1 gene. Taken together, this study indicates that gaseous 3-pentanol triggers induced resistance in Arabidopsis by priming SA and JA signaling pathways. To our knowledge, this is the first report that a volatile compound of an insect sex pheromone triggers plant systemic resistance against a bacterial pathogen.

  2. Building brighter PV business

    International Nuclear Information System (INIS)

    Hacker, R.

    2002-01-01

    The current status and future prospects of the UK market for solar photovoltaic (PV) electricity are briefly discussed. Through the Department of Trade and Industry (DTI), the UK Government has supported research and development (R and D) into PV for a number of years. This programme has now been extended to demonstrating PV systems on houses. Phase 2 - the domestic field trial programme - aims to monitor the performance of individual systems and the impact on a cluster of systems on the electricity network. New funding had allowed a trebling of the size of this programme, which involves both private developers and housing associations. The DTI is also working to promote PV on commercial buildings, eg the installation of BP Solar PV systems at BP petrol stations. The PV industry in the UK is technically strong and is working to overcome the barriers in the UK to greater uptake of the technology (including cost, conservatism, legal requirements and metering practices). Improvements are expected in a number of recent initiatives in the electricity industry to boost PV use and the PV industry is lobbying for PV to be included in the Enhanced Capital Allowances (ECA) scheme

  3. Comparative genome analysis of pathogenic and non-pathogenic Clavibacter strains reveals adaptations to their lifestyle

    OpenAIRE

    Załuga, Joanna; Stragier, Pieter; Baeyen, Steve; Haegeman, Annelies; Van Vaerenbergh, Johan; Maes, Martine; De Vos, Paul

    2014-01-01

    Background The genus Clavibacter harbors economically important plant pathogens infecting agricultural crops such as potato and tomato. Although the vast majority of Clavibacter strains are pathogenic, there is an increasing number of non-pathogenic isolates reported. Non-pathogenic Clavibacter strains isolated from tomato seeds are particularly problematic because they affect the current detection and identification tests for Clavibacter michiganensis subsp. michiganensis (Cmm), which is reg...

  4. Structurally designed attenuated subunit vaccines for S. aureus LukS-PV and LukF-PV confer protection in a mouse bacteremia model.

    Directory of Open Access Journals (Sweden)

    Hatice Karauzum

    Full Text Available Previous efforts towards S. aureus vaccine development have largely focused on cell surface antigens to induce opsonophagocytic killing aimed at providing sterile immunity, a concept successfully applied to other Gram-positive pathogens such as Streptococcus pneumoniae. However, these approaches have largely failed, possibly in part due to the remarkable diversity of the staphylococcal virulence factors such as secreted immunosuppressive and tissue destructive toxins. S. aureus produces several pore-forming toxins including the single subunit alpha hemolysin as well as bicomponent leukotoxins such as Panton-Valentine leukocidin (PVL, gamma hemolysins (Hlg, and LukED. Here we report the generation of highly attenuated mutants of PVL subunits LukS-PV and LukF-PV that were rationally designed, based on an octameric structural model of the toxin, to be deficient in oligomerization. The attenuated subunit vaccines were highly immunogenic and showed significant protection in a mouse model of S. aureus USA300 sepsis. Protection against sepsis was also demonstrated by passive transfer of rabbit immunoglobulin raised against LukS-PV. Antibodies to LukS-PV inhibited the homologous oligomerization of LukS-PV with LukF-PV as well heterologous oligomerization with HlgB. Importantly, immune sera from mice vaccinated with the LukS mutant not only inhibited the PMN lytic activity produced by the PVL-positive USA300 but also blocked PMN lysis induced by supernatants of PVL-negative strains suggesting a broad protective activity towards other bicomponent toxins. These findings strongly support the novel concept of an anti-virulence, toxin-based vaccine intended for prevention of clinical S. aureus invasive disease, rather than achieving sterile immunity. Such a multivalent vaccine may include attenuated leukotoxins, alpha hemolysin, and superantigens.

  5. Building opportunities in the U.S. for PV (PV:BONUS): A progress report

    International Nuclear Information System (INIS)

    Taylor, R.W.

    1994-01-01

    Five contract teams are developing photovoltaic (PV) products that will have a significant impact on building-integrated PV systems. The product lines that these teams are pursuing include roofing materials, building facade materials, PV integrated into modular homes, ac-PV modules, and utility-dispatchable PV systems. The objective of these efforts is to develop product and market opportunities that can provide for the introduction of PV into the buildings market sector at higher allowable installed systems costs than conventional ground- or roof-mounted systems. Each of the teams has a unique approach, and synergistic opportunities among teams are beginning to emerge. This paper reviews the product and market development efforts of these teams and describes the links between the product efforts and parallel analytical work to develop PV as a demand-side management option

  6. Expression of the Grape VaSTS19 Gene in Arabidopsis Improves Resistance to Powdery Mildew and Botrytis cinerea but Increases Susceptibility to Pseudomonas syringe pv Tomato DC3000.

    Science.gov (United States)

    Wang, Yaqiong; Wang, Dejun; Wang, Fan; Huang, Li; Tian, Xiaomin; van Nocker, Steve; Gao, Hua; Wang, Xiping

    2017-09-17

    Stilbene synthase (STS) is a key enzyme that catalyzes the biosynthesis of resveratrol compounds and plays an important role in disease resistance. The molecular pathways linking STS with pathogen responses and their regulation are not known. We isolated an STS gene, VaSTS19 , from a Chinese wild grape, Vitis amurensis Rupr. cv. "Tonghua-3", and transferred this gene to Arabidopsis . We then generated VaSTS19 -expressing Arabidopsis lines and evaluated the functions of VaSTS19 in various pathogen stresses, including powdery mildew, B. cinerea and Pseudomonas syringae pv. tomato DC3000 ( Pst DC3000). VaSTS19 enhanced resistance to powdery mildew and B. cinerea , but increased susceptibility to Pst DC3000. Aniline blue staining revealed that VaSTS19 transgenic lines accumulated more callose compared to nontransgenic control plants, and showed smaller stomatal apertures when exposed to pathogen-associated molecular patterns (flagellin fragment (flg22) or lipopolysaccharides (LPS)). Analysis of the expression of several disease-related genes suggested that VaSTS19 expression enhanced defense responses though salicylic acid (SA) and/or jasmonic acid (JA) signaling pathways. These findings provide a deeper insight into the function of STS genes in defense against pathogens, and a better understanding of the regulatory cross talk between SA and JA pathways.

  7. Host range and symptomatology of Pepino mosaic virus strains occurring in Europe

    NARCIS (Netherlands)

    Blystad, Dag Ragnar; Vlugt, van der René; Alfaro-Fernández, Ana; Carmen Córdoba, del María; Bese, Gábor; Hristova, Dimitrinka; Pospieszny, Henryk; Mehle, Nataša; Ravnikar, Maja; Tomassoli, Laura; Varveri, Christina; Nielsen, Steen Lykke

    2015-01-01

    Pepino mosaic virus (PepMV) has caused great concern in the greenhouse tomato industry after it was found causing a new disease in tomato in 1999. The objective of this paper is to investigate alternative hosts and compare important biological characteristics of the three PepMV strains occurring

  8. Host range of symptomatology of Pepino mosaic virus strains occurring in Europe

    DEFF Research Database (Denmark)

    Blystad, Dag-Ragnar; van der Vlugt, René; Alfaro-Fernández, Ana

    2015-01-01

    Pepino mosaic virus (PepMV) has caused great concern in the greenhouse tomato industry after it was found causing a new disease in tomato in 1999. The objective of this paper is to investigate alternative hosts and compare important biological characteristics of the three PepMV strains occurring...

  9. Isolation of Enterobacter cowanii in tomatoes after gamma irradiation; Isolamento de Enterobacter cowanii em tomates apos irradiacao gama

    Energy Technology Data Exchange (ETDEWEB)

    Vicalvi, M.C.V.; Solidonio, E.G.; Silva, M.A.; Colaco, W., E-mail: claudiavicalvi@hotmail.com [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Programa de Pos Graduacao em Tecnologias Energeticas e Nucleares; Silva, G.R. da; Sena, K.X.F.R de [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Lab. de Antibioticos

    2013-08-15

    The tomato is one of the most consumed fruit in the world. Bacteria of the family Enterobacteriaceae are responsible for large outbreaks of gastroenteritis. Irradiation is a physical method which reduces waste by eliminating spoilage organisms in foods. The objective of this study was to identify and determine the resistance profile of micro-organisms of the family Enterobacteriaceae from irradiated tomatoes. Were used three batches each containing 80 tomatoes, and divided in control and irradiated. The samples were individually properly identified as the irradiation dose applied. The material was subjected to irradiation with gamma rays, for irradiating with a cobalt-60 source, using doses: 1.0, 1.5 and 2 kGy (6,060 kGy/h). For microbiological analysis tomatoes were cut out, and removing the shells to obtain samples weighing 25g. Each sample was transferred to an Erlenmeyer containing sterilized water, stirring the assembly mechanically. Aliquots of the wash waters were sown in differential and selective media. After reisolation, the colonies were subjected to Gram staining then performed biochemical tests for identification. The antibiotic susceptibility tests were performed according to CLSI (Clinical Laboratory Standard Institute). It was isolated three strains of Enterobacter cowanii in tomato samples irradiated with a dose of 1.0 kGy, without isolating the other doses. As for the resistance profile, the strains were resistant to Ampicillin identified. Gamma irradiation at a dose of 1.5 and 2 kGy was effective in tomatoes as well as the micro-organism isolated after irradiation showed no profile of multidrug resistance. (author)

  10. Studies on the O-specific polysaccharide of the lipopolysaccharide from the Pseudomonas mediterranea strain C5P1rad1, a bacterium pathogenic of tomato and chrysanthemum.

    Science.gov (United States)

    Zdorovenko, Evelina L; Cimmino, Alessio; Marchi, Guido; Shashkov, Alexander S; Fiori, Mario; Knirel, Yuriy A; Evidente, Antonio

    2017-08-07

    An O-specific polysaccharide (OPS) was isolated from the lipopolysaccharide of Pseudomonas mediterranea strain C5P1rad1, the causal agents of tomato pith necrosis and Chrysanthemum stem rot, and studied by one- and two-dimensional 1 H and 13 C NMR spectroscopy. The following structure of the trisaccharide repeating unit of the OPS was established, which, to our knowledge, is unique among the known bacterial polysaccharide structures: →4)-β-d-ManpNAc3NAcA-(1 → 4)-β-d-ManpNAc3NAcA-(1 → 3)-α-d-QuipNAc4NAc-(1→ where QuiNAc4NAc and ManNAc3NAcA indicate 2,4-diacetamido-2,4,6-trideoxyglucose and 2,3-diacetamido-2,3-dideoxymannuronic acid, respectively. Pre-treatment of leaves with LPS or OPS preparations at 250 and 50 μg mL -1 did not inhibit development of a hypersensitivity reaction induced by P. mediterranea C5P1rad1 on tobacco, tomato and chrysanthemum plants. The same preparations at 250 μg mL -1 partially prevented elicitation of the hypersensitivity reaction by Pseudomonas syringae KVPT7RC on chrysanthemum but not tobacco and tomato. Copyright © 2017. Published by Elsevier Ltd.

  11. Jasmonate ZIM-domain (JAZ protein regulates host and nonhost pathogen-induced cell death in tomato and Nicotiana benthamiana.

    Directory of Open Access Journals (Sweden)

    Yasuhiro Ishiga

    Full Text Available The nonhost-specific phytotoxin coronatine (COR produced by several pathovars of Pseudomonas syringae functions as a jasmonic acid-isoleucine (JA-Ile mimic and contributes to disease development by suppressing plant defense responses and inducing reactive oxygen species in chloroplast. It has been shown that the F-box protein CORONATINE INSENSITIVE 1 (COI1 is the receptor for COR and JA-Ile. JASMONATE ZIM DOMAIN (JAZ proteins act as negative regulators for JA signaling in Arabidopsis. However, the physiological significance of JAZ proteins in P. syringae disease development and nonhost pathogen-induced hypersensitive response (HR cell death is not completely understood. In this study, we identified JAZ genes from tomato, a host plant for P. syringae pv. tomato DC3000 (Pst DC3000, and examined their expression profiles in response to COR and pathogens. Most JAZ genes were induced by COR treatment or inoculation with COR-producing Pst DC3000, but not by the COR-defective mutant DB29. Tomato SlJAZ2, SlJAZ6 and SlJAZ7 interacted with SlCOI1 in a COR-dependent manner. Using virus-induced gene silencing (VIGS, we demonstrated that SlJAZ2, SlJAZ6 and SlJAZ7 have no effect on COR-induced chlorosis in tomato and Nicotiana benthamiana. However, SlJAZ2-, SlJAZ6- and SlJAZ7-silenced tomato plants showed enhanced disease-associated cell death to Pst DC3000. Furthermore, we found delayed HR cell death in response to the nonhost pathogen Pst T1 or a pathogen-associated molecular pattern (PAMP, INF1, in SlJAZ2- and SlJAZ6-silenced N. benthamiana. These results suggest that tomato JAZ proteins regulate the progression of cell death during host and nonhost interactions.

  12. Comparative genome analysis of pathogenic and non-pathogenic Clavibacter strains reveals adaptations to their lifestyle.

    Science.gov (United States)

    Załuga, Joanna; Stragier, Pieter; Baeyen, Steve; Haegeman, Annelies; Van Vaerenbergh, Johan; Maes, Martine; De Vos, Paul

    2014-05-22

    The genus Clavibacter harbors economically important plant pathogens infecting agricultural crops such as potato and tomato. Although the vast majority of Clavibacter strains are pathogenic, there is an increasing number of non-pathogenic isolates reported. Non-pathogenic Clavibacter strains isolated from tomato seeds are particularly problematic because they affect the current detection and identification tests for Clavibacter michiganensis subsp. michiganensis (Cmm), which is regulated with a zero tolerance in tomato seed. Their misidentification as pathogenic Cmm hampers a clear judgment on the seed quality and health. To get more insight in the genetic features linked to the lifestyle of these bacteria, a whole-genome sequence of the tomato seed-borne non-pathogenic Clavibacter LMG 26808 was determined. To gain a better understanding of the molecular determinants of pathogenicity, the genome sequence of LMG 26808 was compared with that of the pathogenic Cmm strain (NCPPB 382). The comparative analysis revealed that LMG 26808 does not contain plasmids pCM1 and pCM2 and also lacks the majority of important virulence factors described so far for pathogenic Cmm. This explains its apparent non-pathogenic nature in tomato plants. Moreover, the genome analysis of LMG 26808 detected sequences from a plasmid originating from a member of Enterobacteriaceae/Klebsiella relative. Genes received that way and coding for antibiotic resistance may provide a competitive advantage for survival of LMG 26808 in its ecological niche. Genetically, LMG 26808 was the most similar to the pathogenic Cmm NCPPB 382 but contained more mobile genetic elements. The genome of this non-pathogenic Clavibacter strain contained also a high number of transporters and regulatory genes. The genome sequence of the non-pathogenic Clavibacter strain LMG 26808 and the comparative analyses with other pathogenic Clavibacter strains provided a better understanding of the genetic bases of virulence and

  13. PV ready roofing systems

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    The integration of PV technology into roofs of houses has become very popular in the United States, Japan, Germany and The Netherlands. There could be a considerable market in the UK for these systems, given the large number of houses that are projected to be built in the next 10 years, and taking account of increased awareness of energy issues. A significant proportion of the market share of annual installed PV is for solar PV systems installed into homes (currently 15%), this is expected to rise to 23% (900MW) by 2010. The grid connected roof and building mounted facade systems represent the fastest growing market for PV systems in Europe. In conclusion, therefore, innovative approached for fixing PV technology onto roofs have been identified for both domestic roofs and for the commercial sector. With reference to production methodologies within the roofing industry, both approaches should be capable of being designed with PV-ready connections suitable for fixing PV modules at a later date. This will help overcome the key barriers of cost of installation, skills required and the lack of retrofit potential. Based on the results of this project, Sustainable Energy together with PV Systems are keen to take forward the full research and development of PV-ready systems for both the domestic and commercial sectors.

  14. Sensorless PV Array Diagnostic Method for Residential PV Systems

    DEFF Research Database (Denmark)

    Sera, Dezso; Spataru, Sergiu; Mathe, Laszlo

    2011-01-01

    This work proposes a temperature and irradiance sensorless diagnostic method suitable for small residential PV installations, focusing on detection of partial shadows. The method works by detection of failures in crystalline silicone PV arrays by concomitant monitoring of some of their key...

  15. Hygienic quality of traditional processing and stability of tomato (Lycopersicon esculentum) puree in Togo.

    Science.gov (United States)

    Ameyapoh, Yaovi; de Souza, Comlan; Traore, Alfred S

    2008-09-01

    Microbiological and physicochemical qualities of a tomato (Lycopersicon esculentum) puree production line (ripe tomato, washing, cutting, pounding, bleaching, straining, bottling and pasteurization) and its preservation in Togo, West Africa, were studied using the HACCP method. Samples generated during the steps described previously were analyzed by determining sensory, chemical and microbiological characteristics. Samples were analyzed using MPN for coliform populations and plate count methodology for other bacteria. The microorganisms involved in spoilage of the opened products were moulds of genera Penicillium, Aspergillus, Fusarium, Geotrichum, Mucor and gram-positive Bacillus bacteria. The preserved tomato puree exhibited a pH value of 4.3, 90% water content, 0.98 water activity (aw) and an average ascorbic acid level of 27.3mg/100g. Results showed that the critical control point (CCP) of this tomato puree processing line is the pasteurization stage. The analysis of selected microbiological and physicochemical parameters during the preservation of bottled tomato puree indicated that this product was stable over 22 months at 29 degrees C. But the stability of the opened product stored at 29 degrees C did not exceed two months.

  16. Transposon mutagenesis reveals differential pathogenesis of Ralstonia solanacearum on tomato and Arabidopsis.

    Science.gov (United States)

    Lin, Yu-Mei; Chou, I-Chun; Wang, Jaw-Fen; Ho, Fang-I; Chu, Yu-Ju; Huang, Pei-Cheng; Lu, Der-Kang; Shen, Hwei-Ling; Elbaz, Mounira; Huang, Shu-Mei; Cheng, Chiu-Ping

    2008-09-01

    Ralstonia solanacearum causes a deadly wilting disease on a wide range of crops. To elucidate pathogenesis of this bacterium in different host plants, we set out to identify R. solanacearum genes involved in pathogenesis by screening random transposon insertion mutants of a highly virulent strain, Pss190, on tomato and Arabidopsis thaliana. Mutants exhibiting various decreased virulence levels on these two hosts were identified. Sequence analysis showed that most, but not all, of the identified pathogenesis genes are conserved among distinct R. solanacearum strains. A few of the disrupted loci were not reported previously as being involved in R. solanacearum pathogenesis. Notably, a group of mutants exhibited differential pathogenesis on tomato and Arabidopsis. These results were confirmed by characterizing allelic mutants in one other R. solanacearum strain of the same phylotype. The significantly decreased mutants' colonization in Arabidopsis was found to be correlated with differential pathogenesis on these two plants. Differential requirement of virulence genes suggests adaptation of this bacterium in different host environments. Together, this study reveals commonalities and differences of R. solanacearum pathogenesis on single solanaceous and nonsolanaceous hosts, and provides important new insights into interactions between R. solanacearum and different host plants.

  17. City and County Solar PV Training Program, Module 2: Screening and Identifying PV Projects

    Energy Technology Data Exchange (ETDEWEB)

    Elgqvist, Emma M [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2018-04-09

    When screening and identifying PV projects, cities and counties should understand the different factors that impact the technical and economic potential of a PV project, the steps of the PV screening process, and how to use REopt Lite to screen a site for PV and storage project potential.

  18. Isolation, identification, and biocontrol of antagonistic bacterium against Botrytis cinerea after tomato harvest

    Directory of Open Access Journals (Sweden)

    Jun-Feng Shi

    Full Text Available ABSTRACT Tomato is one of the most important vegetables in the world. Decay after harvest is a major issue in the development of tomato industry. Currently, the most effective method for controlling decay after harvest is storage of tomato at low temperature combined with usage of chemical bactericide; however, long-term usage of chemical bactericide not only causes pathogen resistance but also is harmful for human health and environment. Biocontrol method for the management of disease after tomato harvest has great practical significance. In this study, antagonistic bacterium B-6-1 strain was isolated from the surface of tomato and identified as Enterobacter cowanii based on morphological characteristics and physiological and biochemical features combined with sequence analysis of 16SrDNA and ropB gene and construction of dendrogram. Effects of different concentrations of antagonistic bacterium E. cowanii suspension on antifungal activity after tomato harvest were analyzed by mycelium growth rate method. Results revealed that antifungal activity was also enhanced with increasing concentrations of antagonistic bacterium; inhibitory rates of 1 × 105 colony-forming units (cfu/mL antagonistic bacterial solution on Fusarium verticillioides, Alternaria tenuissima, and Botrytis cinerea were 46.31%, 67.48%, and 75.67%, respectively. By using in vivo inoculation method, it was further confirmed that antagonistic bacterium could effectively inhibit the occurrence of B. cinerae after tomato harvest, biocontrol effect of 1 × 109 cfu/mL zymotic fluid reached up to 95.24%, and antagonistic bacterium E. cowanii has biocontrol potential against B. cinerea after harvest of fruits and vegetables.

  19. Development and validation of a real-time quantitative PCR assay to detect Xanthomonas axonopodis pv. allii from onion seed.

    Science.gov (United States)

    Robène, Isabelle; Perret, Marion; Jouen, Emmanuel; Escalon, Aline; Maillot, Marie-Véronique; Chabirand, Aude; Moreau, Aurélie; Laurent, Annie; Chiroleu, Frédéric; Pruvost, Olivier

    2015-07-01

    Bacterial blight of onion is an emerging disease threatening world onion production. The causal agent Xanthomonas axonopodis pv. allii is seed transmitted and a reliable and sensitive tool is needed to monitor seed exchanges. A triplex quantitative real-time PCR assay was developed targeting two X. axonopodis pv. allii-specific markers and an internal control chosen in 5.8S rRNA gene from Alliaceae. Amplification of at least one marker indicates the presence of the bacterium in seed extracts. This real-time PCR assay detected all the 79 X. axonopodis pv. allii strains tested and excluded 85.2% of the 135 non-target strains and particularly all 39 saprophytic and pathogenic bacteria associated with onion. Cross-reactions were mainly obtained for strains assigned to nine phylogenetically related X. axonopodis pathovars. The cycle cut-off was estimated statistically at 36.3 considering a risk of false positive of 1%. The limit of detection obtained in at least 95% of the time (LOD 95%) was 5×10(3) CFU/g (colony forming unit/g). The sensitivity threshold was found to be 1 infected seed in 32,790 seeds. This real-time PCR assay should be useful for preventing the long-distance spread of X. axonopodis pv. allii via contaminated seed lots and determining the epidemiology of the bacterium. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. PV power plants

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-07-01

    Within the international seminar of the Ostbayerisches Technologie-Transfer-Institut e.V. (OTTI) at 11th June, 2012 in Munich (Federal Republic of Germany), the following lectures were held: (1) Technical due diligence (Dietmar Obst); (2) Certification / rating system for large PV plants (Robert Pfatischer); (3) O and M requirements (Lars Rulf); (4) IR photography for large scale systems (Bernhard Weinreich); (5) New market models for PV systems - direct marketing and sales of PV electricity (Martin Schneider); (6) Needs and benefits for plant certification for grid connection and operation (Christoph Luetke-Lengerich); (7) Lare volume module testing / Screening in the field and workshop (Semir Merzoug); (8) Dismantling costs of large scale PV plants (Siegfried Schimpf).

  1. Recent evolution of a novel begomovirus causing tomato leaf curl disease in the Al-Batinah region of Oman.

    Science.gov (United States)

    Khan, Akhtar J; Akhtar, Sohail; Singh, Achuit K; Al-Shehi, Adel A; Al-Matrushi, Abdulrahman M; Ammara, Ume; Briddon, Rob W

    2014-03-01

    For last two decades, begomoviruses (family Geminiviridae) have been a major constraint for tomato production in Oman, particularly in the Al-Batinah region, the major agricultural area of Oman. Farms in the Al-Batinah region were surveyed during January-March and November-December in 2012 and January-February in 2013. Leaf samples of tomato plants showing typical leaf curl disease symptoms were collected and analyzed for begomoviruses. Out of fifteen begomovirus clones sequenced, seven were shown to be tomato yellow leaf curl virus strain Oman (TYLCV-OM); three, chili leaf curl virus strain Oman (ChLCV-OM); and one, tomato leaf curl Oman virus (ToLCOMV) - viruses that have previously been shown to occur in Oman. Four sequences were shown to have relatively low percent identity values to known begomoviruses, with the highest (86 %) to isolates of pepper leaf curl Lahore virus, indicating that these should be included in a new species, for which the name "Tomato leaf curl Al Batinah virus" (ToLCABV) is proposed. Although the betasatellite tomato leaf curl betasatellite (ToLCB; 7 full-length sequences isolated) was identified with some isolates of ChLCV-OM, TYLCV-OM and ToLCOMV, it was not identified in association with any of the ToLCABV isolates. Analysis of the sequences of the TYLCV-OM and ToLCOMV isolates characterized here did not show them to differ significantly from previously characterized isolates of these viruses. The three isolates of ChLCV-OM characterized were shown to have a recombination pattern distinct from earlier characterized isolates. ToLCABV was shown to have resulted from recombination between ChLCV-OM and ToLCOMV. A clone of ToLCABV was infectious by Agrobacterium-mediated inoculation to Nicotiana benthamiana and tomato, inducing symptoms typical of those seen in tomato in the field. Additionally, ToLCABV was shown to be able to interact in planta with ToLCB, resulting in a change in symptom phenotype, although the betasatellite did not

  2. Anti-atherosclerotic effects of tomatoes

    Directory of Open Access Journals (Sweden)

    Hidekatsu Yanai

    2017-06-01

    Full Text Available Tomatoes are rich in lycopene, which causes the red coloring of tomatoes. Several reports have suggested lycopene plays a role in the prevention of cardiovascular diseases. In this study, we systematically reviewed the interventional studies using tomatoes or tomato products to understandtheanti-atherosclerotic effects of the tomatoas a functional food. We found that a significantnumber of interventional studies reportedtheanti-atherosclerotic effects of tomatoes, includinganti-obesity effects, hypotensiveeffects, improvement of lipid/glucose metabolismand endothelial function, anti-oxidative and anti-inflammatory effect, and anti-platelet effect; however, the anti-platelet effect was disagreed uponby some studies. Furthermore, we discoveredcooking methods significantlyaffect anti-atherosclerotic effects of tomatoes.

  3. Tomato Preserves.

    Science.gov (United States)

    Stevens, Wendy Tessman

    1996-01-01

    Describes a project in which students selected seeds from two heirloom varieties of tomatoes, sowed the seeds, harvested the tomatoes, and fermented the seeds. Details are provided for each step of the project and the school address is included so that other students can begin similar projects. (DDR)

  4. Tomato type and post-treatment water rinse affect efficacy of acid washes against Salmonella enterica inoculated on stem scars of tomatoes and product quality.

    Science.gov (United States)

    Fan, Xuetong; Gurtler, Joshua B; Sokorai, Kimberly J B

    2018-09-02

    A study was conducted to evaluate the effects of post-treatment rinsing with water on the inactivation efficacy of acid treatments against Salmonella inoculated onto stem scar areas of two types of tomatoes. In addition, impact on fruit quality was investigated during 21 days post-treatment storage at 10 °C. A four-strain cocktail of Salmonella enterica (S. Montevideo, S. Newport, S. Saintpaul, and S. Typhimurium) was inoculated onto stem scar areas of grape and large round tomatoes. The inoculated fruits were then treated for 2 min with the following solutions: water, 2% lactic acid +2% acetic acid +2% levulinic acid, 1.7% lactic acid +1.7% acetic acid +1.7% levulinic acid, and 3% lactic acid +3% acetic acid. After treatments, half of the fruits were rinsed with water while another half were not rinsed. Non-inoculated grape tomatoes for quality analysis were treated with the same solutions with and without subsequent water rinse. Results demonstrated that the acid combinations reduced populations of Salmonella enterica on the stem scar area of grape tomatoes by 1.52-1.90 log CFU/fruit, compared with the non-treated control while water wash and rinse removed the bacterium by only 0.23-0.30 log CFU/fruit. On the stem scar of large round tomatoes, the same acid treatments achieved 3.54 log CFU/fruit reduction of the pathogen. The varying response to the acid washes between grape and large round tomatoes seems to be related to the differences in surface characteristics of stem scar areas observed with SEM. Rinsing with water after acid combination treatments did not significantly affect the efficacy of the treatments in either grape or large round tomatoes. Acidic off-odor was detected on fruits treated with acid combination without water rinse 1 day after treatment while water rinse eliminated the off-odor. The acid treatments with and without water rinse did not consistently affect appearance, color, firmness, or lycopene or ascorbic acid contents of

  5. Physicochemical and microbiological evaluation of sun dried tomatoes in comparison with fresh tomatoes

    International Nuclear Information System (INIS)

    Sohail, M.

    2011-01-01

    The present study was conducted to evaluate the quality of sun dried tomatoes in comparison with fresh tomatoes. Fresh fully ripen tomatoes were washed and cut in thin slices with sterilized stainless steel knife and divided into two lots, one was taken as control and other was dipped in 3% potassium meta bisulfite solution for 5 minutes. The samples were spread over stainless steel trays covered with muslin cloth and kept in solar dehydrator for 5 days at 55 +- 2 deg. C. The physicochemical analyses were carried out in both dried and fresh (control) tomatoes. They were also analyzed microbiologically for bacterial and fugal count. Results showed that sun dried tomatoes are microbiologically safe. The values of moisture content and vitamin C of fresh and sun dried tomatoes statistically differ from each others at probability level of 5 %. The nutrient which is highly affected by sun drying is vitamin C. In fresh tomatoes it was 32.5 mg/100 g which is reduced to 24.6 mg/100 g after sun drying and further reduced to 15.86 mg/100 g during three months storage. The moisture content of the fresh tomatoes was 94.4% which decreased to 8.15% after drying, and then slowly increased to 9.95% in the three months storage. Statistically no major difference was found in the other nutrients during storage, which indicates that sun drying is nutritionally and microbiologically safe and can be used to preserve tomatoes and other fruits and vegetables for off season use. (author)

  6. PV Obelisk - Information system with photovoltaics; PV-Obelisk Orientierungssystem mit Photovoltaik

    Energy Technology Data Exchange (ETDEWEB)

    Ruoss, D.; Rasmussen, J.

    2004-07-01

    This final report for the Swiss Federal Office of Energy (SFOE) describes the development of an information system powered by a photovoltaic (PV) array. As an innovative approach, the 'PV-Obelisk' project is the combination of PV with a multi-functional pillar made of natural stone in an aesthetic way. The PV modules serve both as a power supply and as a design element. Two initial prototypes led the way to a third, optimised consumer configuration that was planned to guarantee maximum user frequency. Test operation in front of the 'Heidiland' motor way restaurant confirmed the market analyses made and delivered the expected results. The product, whose three LCD displays are updated via a mobile telephony-based text-message system, proved its technical reliability and showed a high user frequency. Because of the high overall energy consumption, PV power can only partially contribute to the energy supply needed. Various compromises in the technical and aesthetic areas are discussed that were made for the sake of product acceptance in the market. The range of application areas for such a 'PV Obelisk' are discussed and the need for early co-ordination with urban planners is stressed.

  7. An assessment of adaptive and antagonistic properties of Trichoderma sp. strains in vegetable waste composts

    Directory of Open Access Journals (Sweden)

    Wolna-Maruwka Agnieszka

    2017-12-01

    Full Text Available The experiment consisted in monitoring the count of moulds and three selected Trichoderma sp. isolates (T1 - Trichoderma atroviride, T2 - Trichoderma harzianum, T3 - Trichoderma harzianum in vegetable (onion and tomato waste composted with additives (straw, pig manure. Additionally, the aim of the study was to determine the type of interaction occurring between autochthonous fungi isolated from composts after the end of the thermophilic phase and Trichoderma sp. strains applied in the experiment. Number of microorganisms was determined by the plate method, next the identification was confirmed. The rating scale developed by Mańka was used to determine the type of interactions occurring between microorganisms. The greatest count of moulds in onion waste composts was noted in the object which had simultaneously been inoculated with two strains T1 - T. atroviride and T3 - T. harzianum. The greatest count of moulds was noted in the tomato waste composts inoculated with T2 - T. harzianum strain. Microscope identification revealed that Penicillum sp., Rhizopus sp., Alternaria sp. and Mucor sp. strains were predominant in onion waste composts. In tomato waste composts Penicillium was the predominant genus, followed by Rhizopus. The test of antagonism revealed the inhibitory effect of Trichoderma isolates on most autochthonous strains of moulds. Tomato waste composts proved to be better substrates for the growth and development of Trichoderma sp. isolates. The results of the study show that vegetable waste can be used in agriculture as carriers of antagonistic microorganisms.

  8. Assessment of genetic diversity of Xanthomonas oryzae pv. oryzae

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    @@Bacterial blight of rice, caused by Xanthomonas oryzae pv. Oryzae(Xoo. ), is one of the major rice diseases in China. Making clear the shift of genetic diversity of the pathogen will provide important information for rice breeding. Strains collected from 11 provinces located in Southern region of the Changjiang River in China were assessed by using inoculation method and IS-PCR(Insertion Sequence-Based Polymerase Chain Reaction) analysis.

  9. Cytogenetic and molecular studies on tomato chromosomes using diploid tomato and tomato monosomic additions in tetraploid potato

    NARCIS (Netherlands)

    Chang, S.B.

    2004-01-01

    Geneticists have studied the tomato, Lycopersicon esculentum, for several decades and now obtained a saturated linkage map on which numerous genes controlling morphological traits and disease resistances, and molecular markers have been positioned. They also investigated the chromosomes of tomato,

  10. EFFECTIVE COMPLEX PROCESSING OF RAW TOMATOES

    Directory of Open Access Journals (Sweden)

    AIDA M. GADZHIEVA

    2018-03-01

    Full Text Available Tomatoes grown in the central and southern parts of the country, which contain 5 - 6 % of solids, including 0.13 % of pectin, 0.86 % of fat, 0.5 % of organic acids, 0.5 % minerals, etc. are used as research material. These tomatoes, grown in the mountains, on soils with high salinity, contain high amounts of valuable components and have long term preservation. For the extraction of valuable components from dried tomato pomace, the CO2 extraction method is applied. The technological and environmental feasibility of graded tomato drying in the atmosphere of an inert gas and in a solar drier is evaluated; the scheme of dried tomatoes production is improved; a system for tomato pomace drying is developed; a scheme of tomato powder production from pulp, skin and seeds is developed. The combined method of tomato pomace drying involves the simultaneous use of electromagnetic field of low and ultra-high frequency and blowing hot nitrogen on the product surface. Conducting the drying process in the atmosphere of nitrogen intensifies the process of removing moisture from tomatoes. The expediency of using tomato powder as an enriching additive is proved. Based on the study of the chemical composition of the tomato powder made from the Dagestan varieties, and on the organoleptic evaluation and physicochemical analysis of finished products, we prove the best degree of recoverability of tomato powder in the production of reconstituted juice and tomato beverages.

  11. Induced systemic resistance against Botrytis cinerea by Micromonospora strains isolated from root nodules

    Directory of Open Access Journals (Sweden)

    Pilar eMartínez-Hidalgo

    2015-09-01

    Full Text Available Micromonospora is a Gram positive bacterium that can be isolated from nitrogen fixing nodules from healthy leguminous plants, where they could be beneficial to the plant. Their plant growth promoting activity in legume and non-legume plants has been previously demonstrated. The present study explores the ability of Micromonospora strains to control fungal pathogens and to stimulate plant immunity. Micromonospora strains isolated from surface sterilized nodules of alfalfa showed in vitro antifungal activity against several pathogenic fungi. Moreover, root inoculation of tomato plants with these Micromonospora strains effectively reduced leaf infection by the fungal pathogen Botrytis cinerea, despite spatial separation between both microorganisms. This induced systemic resistance, confirmed in different tomato cultivars, is long lasting. Gene expression analyses evidenced that Micromonospora stimulates the plant capacity to activate defense mechanisms upon pathogen attack. The defensive response of tomato plants inoculated with Micromonospora spp. differs from that of non-inoculated plants, showing a stronger induction of jasmonate-regulated defenses when the plant is challenged with a pathogen. The hypothesis of jasmonates playing a key role in this defense priming effect was confirmed using defense-impaired tomato mutants, since the JA-deficient line def1 was unable to display a long term induced resistance upon Micromonospora spp. inoculation.In conclusion, nodule isolated Micromonospora strains should be considered excellent candidates as biocontrol agents as they combine both direct antifungal activity against plant pathogens and the ability to prime plant immunity.

  12. 21 CFR 155.190 - Canned tomatoes.

    Science.gov (United States)

    2010-04-01

    ... tomatoes. (a) Identity—(1) Description. (i) Canned tomatoes is the food prepared from mature tomatoes...). Without shifting the tomatoes, so incline the sieve as to facilitate drainage of the liquid. Two minutes...

  13. Novel Methods to Determine Feeder Locational PV Hosting Capacity and PV Impact Signatures

    Energy Technology Data Exchange (ETDEWEB)

    Reno, Matthew J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Coogan, Kyle [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Seuss, John [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Broderick, Robert Joseph [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-05-01

    Often PV hosting capacity analysis is performed for a limited number of distribution feeders. For medium - voltage distribution feeders, previous results generally analyze less than 20 feeders, and then the results are extrapolated out to similar types of feeders. Previous hosting capacity research has often focused on determining a single value for the hosting capacity for the entire feeder, whereas this research expands previous hosting capacity work to investigate all the regions of the feeder that may allow many different hosting capacity values wit h an idea called locational hosting capacity (LHC)to determine the largest PV size that can be interconnected at different locations (buses) on the study feeders. This report discusses novel methods for analyzing PV interconnections with advanced simulati on methods. The focus is feeder and location - specific impacts of PV that determine the locational PV hosting capacity. Feeder PV impact signature are used to more precisely determine the local maximum hosting capacity of individual areas of the feeder. T he feeder signature provides improved interconnection screening with certain zones that show the risk of impact to the distribution feeder from PV interconnections.

  14. Expression of the Grape VaSTS19 Gene in Arabidopsis Improves Resistance to Powdery Mildew and Botrytis cinerea but Increases Susceptibility to Pseudomonas syringe pv Tomato DC3000

    Directory of Open Access Journals (Sweden)

    Yaqiong Wang

    2017-09-01

    Full Text Available Stilbene synthase (STS is a key enzyme that catalyzes the biosynthesis of resveratrol compounds and plays an important role in disease resistance. The molecular pathways linking STS with pathogen responses and their regulation are not known. We isolated an STS gene, VaSTS19, from a Chinese wild grape, Vitis amurensis Rupr. cv. “Tonghua-3”, and transferred this gene to Arabidopsis. We then generated VaSTS19-expressing Arabidopsis lines and evaluated the functions of VaSTS19 in various pathogen stresses, including powdery mildew, B. cinerea and Pseudomonas syringae pv. tomato DC3000 (PstDC3000. VaSTS19 enhanced resistance to powdery mildew and B. cinerea, but increased susceptibility to PstDC3000. Aniline blue staining revealed that VaSTS19 transgenic lines accumulated more callose compared to nontransgenic control plants, and showed smaller stomatal apertures when exposed to pathogen-associated molecular patterns (flagellin fragment (flg22 or lipopolysaccharides (LPS. Analysis of the expression of several disease-related genes suggested that VaSTS19 expression enhanced defense responses though salicylic acid (SA and/or jasmonic acid (JA signaling pathways. These findings provide a deeper insight into the function of STS genes in defense against pathogens, and a better understanding of the regulatory cross talk between SA and JA pathways.

  15. The tomato sauce making process affects the bioaccessibility and bioavailability of tomato phenolics: a pharmacokinetic study.

    Science.gov (United States)

    Martínez-Huélamo, Miriam; Tulipani, Sara; Estruch, Ramón; Escribano, Elvira; Illán, Montserrat; Corella, Dolores; Lamuela-Raventós, Rosa M

    2015-04-15

    Tomato sauce is the most commonly consumed processed tomato product worldwide, but very little is known about how the manufacturing process may affect the phenolic composition and bioavailability after consumption. In a prospective randomised, cross-over intervention study, we analysed the plasma and urinary levels of tomato phenolic compounds and their metabolites after acute consumption of raw tomatoes and tomato sauce, enriched or not with refined olive oil during production. Respectively, eleven and four phenolic metabolites were found in urine and plasma samples. The plasma concentration and urinary excretion of naringenin glucuronide were both significantly higher after the consumption of tomato sauce than raw tomatoes. The results suggest that the mechanical and thermal treatments during tomato sauce manufacture may help to deliver these potentially bioactive phenolics from the food matrix more effectively than the addition of an oil component, thus increasing their bioavailability. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Energy balance of the global photovoltaic (PV) industry--is the PV industry a net electricity producer?

    Science.gov (United States)

    Dale, Michael; Benson, Sally M

    2013-04-02

    A combination of declining costs and policy measures motivated by greenhouse gas (GHG) emissions reduction and energy security have driven rapid growth in the global installed capacity of solar photovoltaics (PV). This paper develops a number of unique data sets, namely the following: calculation of distribution of global capacity factor for PV deployment; meta-analysis of energy consumption in PV system manufacture and deployment; and documentation of reduction in energetic costs of PV system production. These data are used as input into a new net energy analysis of the global PV industry, as opposed to device level analysis. In addition, the paper introduces a new concept: a model tracking energetic costs of manufacturing and installing PV systems, including balance of system (BOS) components. The model is used to forecast electrical energy requirements to scale up the PV industry and determine the electricity balance of the global PV industry to 2020. Results suggest that the industry was a net consumer of electricity as recently as 2010. However, there is a >50% that in 2012 the PV industry is a net electricity provider and will "pay back" the electrical energy required for its early growth before 2020. Further reducing energetic costs of PV deployment will enable more rapid growth of the PV industry. There is also great potential to increase the capacity factor of PV deployment. These conclusions have a number of implications for R&D and deployment, including the following: monitoring of the energy embodied within PV systems; designing more efficient and durable systems; and deploying PV systems in locations that will achieve high capacity factors.

  17. Disease control effect of strevertenes produced by Streptomyces psammoticus against tomato fusarium wilt.

    Science.gov (United States)

    Kim, Jeong Do; Han, Jae Woo; Lee, Sung Chul; Lee, Dongho; Hwang, In Cheon; Kim, Beom Seok

    2011-03-09

    During screening of microorganisms producing antifungal metabolites, Streptomyces psammoticus strain KP1404 was isolated. The culture extract of this strain showed potent disease control efficacy against Fusarium wilt on tomato plants. The antifungal metabolites ST-1 and ST-2 were isolated from the culture extract using a variety of chromatographic procedures. On the basis of MS and NMR spectrometric analysis, the structures of the antifungal active compounds ST-1 and ST-2 were determined to be the polyene antibiotics strevertene A and strevertene B, respectively. In vitro, strevertenes A and B showed inhibitory effects against the mycelial growth of Alternaria mali , Aspergillus oryzae , Cylindrocarpon destructans , Colletotrichum orbiculare , Fusarium oxysporum f.sp. lycopersici, and Sclerotinia sclerotiorum , even at concentrations of 4-16 μg/mL. Fusarium wilt development on tomato plants was strongly retarded by treatment with 1 μg/mL of these strevertenes. The disease control efficacies of strevertenes on Fusarium wilt were as remarkable as that of benomyl.

  18. Zesty Tomato Soup

    Science.gov (United States)

    ... https://medlineplus.gov/recipe/zestytomatosoup.html Zesty Tomato Soup To use the sharing features on this page, ... Number of Servings: 4 Not your traditional tomato soup, this quick-cooking dish can be a side ...

  19. Comparative genomics reveals diversity among xanthomonads infecting tomato and pepper

    LENUS (Irish Health Repository)

    Potnis, Neha

    2011-03-11

    Abstract Background Bacterial spot of tomato and pepper is caused by four Xanthomonas species and is a major plant disease in warm humid climates. The four species are distinct from each other based on physiological and molecular characteristics. The genome sequence of strain 85-10, a member of one of the species, Xanthomonas euvesicatoria (Xcv) has been previously reported. To determine the relationship of the four species at the genome level and to investigate the molecular basis of their virulence and differing host ranges, draft genomic sequences of members of the other three species were determined and compared to strain 85-10. Results We sequenced the genomes of X. vesicatoria (Xv) strain 1111 (ATCC 35937), X. perforans (Xp) strain 91-118 and X. gardneri (Xg) strain 101 (ATCC 19865). The genomes were compared with each other and with the previously sequenced Xcv strain 85-10. In addition, the molecular features were predicted that may be required for pathogenicity including the type III secretion apparatus, type III effectors, other secretion systems, quorum sensing systems, adhesins, extracellular polysaccharide, and lipopolysaccharide determinants. Several novel type III effectors from Xg strain 101 and Xv strain 1111 genomes were computationally identified and their translocation was validated using a reporter gene assay. A homolog to Ax21, the elicitor of XA21-mediated resistance in rice, and a functional Ax21 sulfation system were identified in Xcv. Genes encoding proteins with functions mediated by type II and type IV secretion systems have also been compared, including enzymes involved in cell wall deconstruction, as contributors to pathogenicity. Conclusions Comparative genomic analyses revealed considerable diversity among bacterial spot pathogens, providing new insights into differences and similarities that may explain the diverse nature of these strains. Genes specific to pepper pathogens, such as the O-antigen of the lipopolysaccharide cluster

  20. Transgenic tomato hybrids resistant to tomato spotted wilt virus infection.

    NARCIS (Netherlands)

    Haan, de P.; Ultzen, T.; Prins, M.; Gielen, J.; Goldbach, R.; Grinsven, van M.

    1996-01-01

    Tomato spotted wilt virus (TSWV) infections cause significant economic losses in the commercial culture of tomato (Lycopersicon esculentum). Culture practices have only been marginally effective in controlling TSWV. The ultimate way to minimize losses caused by TSWV is resistant varieties. These can

  1. Coexistence between neighbours

    DEFF Research Database (Denmark)

    Shenge, K.C.; Mabagala, R.B.; Mortensen, C A Nieves Paulino

    2008-01-01

    Experiments were conducted under laboratory and screenhouse conditions to study the coexistence between Pseudomonas syringae pv. tomato and Xanthomonas campestris pv. vesicatoria, incitants of bacterial speck and bacterial spot diseases of tomato. Results of in vitro studies showed that when mixe...

  2. Induction of mutations for nematode resistance in tomato

    International Nuclear Information System (INIS)

    Alameddine, A.

    1976-01-01

    The objective of this work is to develop resistance to root-knot nematodes in tomato by induction, selection and utilization of the newly created resistant strains. Seeds of two varieties of tomato Lycopersicon esculentum L., namely Amcopack and Supermarmande, were subjected to various doses of gamma rays ranging from 10 Krads to 40 Krads in an effort to gain resistance to Meloidogyne incognita Chitwood, the prevalent species of nematodes in Lebanon. The variety Supermarmande seemed not to be affected by irradiation while Amcopack gained some resistance with a corresponding increase in the dose of radiation. The data suggest that in a variety like Amcopack, irradiation may stimulate resistance while in others like Supermarmande, susceptibility is not reduced with a corresponding increase of dosage. Those alterations in reaction within varieties may be due to genetic differences which allow some varieties to acquire resistance to nematodes when exposed to certain dosages, while others to suffer seriously due to sensitivity. (author)

  3. The Ca2+ induced two-component system, CvsSR regulates the Type III secretion system and the extracytoplasmic function sigma-factor AlgU in Pseudomonas syringae pv. tomato DC3000.

    Science.gov (United States)

    Fishman, Maxwell R; Zhang, Johnson; Bronstein, Philip A; Stodghill, Paul; Filiatrault, Melanie J

    2017-12-20

    Two-component systems (TCSs) of bacteria regulate many different aspects of the bacterial life cycle including pathogenesis. Most TCSs remain uncharacterized with no information about the signal(s) or regulatory targets and/or role in bacterial pathogenesis. Here, we characterized a TCS in the plant-pathogenic bacterium Pseudomonas syringae pv. tomato DC3000 ( Pto ) composed of the histidine kinase, CvsS, and the response regulator, CvsR. CvsSR is necessary for virulence of Pto , since ΔcvsS and ΔcvsR strains produced fewer symptoms and demonstrated reduced growth on multiple hosts as compared to WT. We discovered that expression of cvsSR is induced by Ca 2+ concentrations found in leaf apoplastic fluid. Thus, Ca 2+ can be added to the list of signals that promote pathogenesis of Pto during host colonization. Through chromatin immunoprecipitation followed by next generation sequencing (ChIP-seq) and global transcriptome analysis (RNA-seq) we discerned the CvsR regulon. CvsR directly activated expression of the type III secretion system regulators, hrpR and hrpS , that regulates Pto virulence in a type III secretion system dependent manner. CvsR also indirectly repressed transcription of the extracytoplasmic sigma factor algU and production of alginate. Phenotypic analysis determined that CvsSR inversely regulated biofilm formation, swarming motility, and cellulose production in a Ca 2+ -dependent manner. Overall, our results show that CvsSR is a key regulatory hub critical for interaction with host plants. Importance Pathogenic bacteria must be able to react and respond to the surrounding environment, make use of available resources, and avert or counter host immune responses. Often, these abilities rely on two-component systems (TCSs) composed of interacting proteins that modulate gene expression. We identified a TCS in the plant-pathogenic bacterium Pseudomonas syringae that responds to the presence of calcium, which is an important signal during the plant

  4. PV Thermal systems: PV panels supplying renewable electricity and heat

    NARCIS (Netherlands)

    Helden, van W.G.J.; Zolingen, van R.J.C.; Zondag, H.A.

    2004-01-01

    With PV Thermal panels sunlight is converted into electricity and heat simultaneously. Per unit area the total efficiency of a PVT panel is higher than the sum of the efficiencies of separate PV panels and solar thermal collectors. During the last 20 years research into PVT techniques and concepts

  5. Brunenders: a partially attenuated historic poliovirus type I vaccine strain.

    Science.gov (United States)

    Sanders, Barbara P; Liu, Ying; Brandjes, Alies; van Hoek, Vladimir; de Los Rios Oakes, Isabel; Lewis, John; Wimmer, Eckard; Custers, Jerome H H V; Schuitemaker, Hanneke; Cello, Jeronimo; Edo-Matas, Diana

    2015-09-01

    Brunenders, a type I poliovirus (PV) strain, was developed in 1952 by J. F. Enders and colleagues through serial in vitro passaging of the parental Brunhilde strain, and was reported to display partial neuroattenuation in monkeys. This phenotype of attenuation encouraged two vaccine manufacturers to adopt Brunenders as the type I component for their inactivated poliovirus vaccines (IPVs) in the 1950s, although today no licensed IPV vaccine contains Brunenders. Here we confirmed, in a transgenic mouse model, the report of Enders on the reduced neurovirulence of Brunenders. Although dramatically neuroattenuated relative to WT PV strains, Brunenders remains more virulent than the attenuated oral vaccine strain, Sabin 1. Importantly, the neuroattenuation of Brunenders does not affect in vitro growth kinetics and in vitro antigenicity, which were similar to those of Mahoney, the conventional type I IPV vaccine strain. We showed, by full nucleotide sequencing, that Brunhilde and Brunenders differ at 31 nucleotides, eight of which lead to amino acid changes, all located in the capsid. Upon exchanging the Brunenders capsid sequence with that of the Mahoney capsid, WT neurovirulence was regained in vivo, suggesting a role for the capsid mutations in Brunenders attenuation. To date, as polio eradication draws closer, the switch to using attenuated strains for IPV is actively being pursued. Brunenders preceded this novel strategy as a partially attenuated IPV strain, accompanied by decades of successful use in the field. Providing data on the attenuation of Brunenders may be of value in the further construction of attenuated PV strains to support the grand pursuit of the global eradication of poliomyelitis.

  6. The in planta transcriptome of Ralstonia solanacearum: conserved physiological and virulence strategies during bacterial wilt of tomato.

    Science.gov (United States)

    Jacobs, Jonathan M; Babujee, Lavanya; Meng, Fanhong; Milling, Annett; Allen, Caitilyn

    2012-01-01

    Plant xylem fluid is considered a nutrient-poor environment, but the bacterial wilt pathogen Ralstonia solanacearum is well adapted to it, growing to 10(8) to 10(9) CFU/g tomato stem. To better understand how R. solanacearum succeeds in this habitat, we analyzed the transcriptomes of two phylogenetically distinct R. solanacearum strains that both wilt tomato, strains UW551 (phylotype II) and GMI1000 (phylotype I). We profiled bacterial gene expression at ~6 × 10(8) CFU/ml in culture or in plant xylem during early tomato bacterial wilt pathogenesis. Despite phylogenetic differences, these two strains expressed their 3,477 common orthologous genes in generally similar patterns, with about 12% of their transcriptomes significantly altered in planta versus in rich medium. Several primary metabolic pathways were highly expressed during pathogenesis. These pathways included sucrose uptake and catabolism, and components of these pathways were encoded by genes in the scrABY cluster. A UW551 scrA mutant was significantly reduced in virulence on resistant and susceptible tomato as well as on potato and the epidemiologically important weed host Solanum dulcamara. Functional scrA contributed to pathogen competitive fitness during colonization of tomato xylem, which contained ~300 µM sucrose. scrA expression was induced by sucrose, but to a much greater degree by growth in planta. Unexpectedly, 45% of the genes directly regulated by HrpB, the transcriptional activator of the type 3 secretion system (T3SS), were upregulated in planta at high cell densities. This result modifies a regulatory model based on bacterial behavior in culture, where this key virulence factor is repressed at high cell densities. The active transcription of these genes in wilting plants suggests that T3SS has a biological role throughout the disease cycle. IMPORTANCE Ralstonia solanacearum is a widespread plant pathogen that causes bacterial wilt disease. It inflicts serious crop losses on tropical

  7. Effect of plant resistance and BioAct WG (Purpureocillium lilacinum strain 251) on Meloidogyne incognita in a tomato-cucumber rotation in a greenhouse.

    Science.gov (United States)

    Giné, Ariadna; Sorribas, Francisco J

    2017-05-01

    The effectiveness of combining resistant tomato with BioAct WG (Purpureocillium lilacinum strain 251, Pl251) against Meloidogyne incognita was assessed in a tomato-cucumber rotation in a greenhouse over 2 years. Additionally, the enzymatic activity of the fungus, the percentage of fungal egg and juvenile parasitism, cardinal temperatures and the effect of water potential on mycelial growth and the soil receptivity to Pl251 were determined in vitro. Plant resistance was the only factor that suppressed nematode and crop yield losses. Percentage of egg parasitism in plots treated with BioAct WG was less than 2.6%. However, under in vitro conditions, Pl251 showed protease, lipase and chitinase activities and parasitised 94.5% of eggs, but no juveniles. Cardinal temperatures were 14.2, 24-26 and 35.4 °C. The maximum Pl251 mycelial growth was at -0.25 MPa and 25 °C. Soil temperatures and water potential in the greenhouse were in the range of the fungus. However, soil receptivity was lower in greenhouse soil, irrespective of sterilisation, than in sterilised sand. Plant resistance was the only factor able to suppress nematode densities, disease severity and yield losses, and to protect the following cucumber crop. Environmental factors involved in soil receptivity could have negatively affected fungus effectiveness. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  8. Comparison of three different methods of perturbing the potential vorticity field in mesoscale forecasts of Mediterranean heavy precipitation events: PV-gradient, PV-adjoint and PV-satellite

    Science.gov (United States)

    Vich, M.; Romero, R.; Richard, E.; Arbogast, P.; Maynard, K.

    2010-09-01

    Heavy precipitation events occur regularly in the western Mediterranean region. These events often have a high impact on the society due to economic and personal losses. The improvement of the mesoscale numerical forecasts of these events can be used to prevent or minimize their impact on the society. In previous studies, two ensemble prediction systems (EPSs) based on perturbing the model initial and boundary conditions were developed and tested for a collection of high-impact MEDEX cyclonic episodes. These EPSs perturb the initial and boundary potential vorticity (PV) field through a PV inversion algorithm. This technique ensures modifications of all the meteorological fields without compromising the mass-wind balance. One EPS introduces the perturbations along the zones of the three-dimensional PV structure presenting the local most intense values and gradients of the field (a semi-objective choice, PV-gradient), while the other perturbs the PV field over the MM5 adjoint model calculated sensitivity zones (an objective method, PV-adjoint). The PV perturbations are set from a PV error climatology (PVEC) that characterizes typical PV errors in the ECMWF forecasts, both in intensity and displacement. This intensity and displacement perturbation of the PV field is chosen randomly, while its location is given by the perturbation zones defined in each ensemble generation method. Encouraged by the good results obtained by these two EPSs that perturb the PV field, a new approach based on a manual perturbation of the PV field has been tested and compared with the previous results. This technique uses the satellite water vapor (WV) observations to guide the correction of initial PV structures. The correction of the PV field intents to improve the match between the PV distribution and the WV image, taking advantage of the relation between dark and bright features of WV images and PV anomalies, under some assumptions. Afterwards, the PV inversion algorithm is applied to run

  9. COMPLEX PROCESSING TECHNOLOGY OF TOMATO RAW MATERIALS

    Directory of Open Access Journals (Sweden)

    A. M. Gadzhieva

    2015-01-01

    Full Text Available Tomatoes grown in the central and southern parts of the country, which contain 5-6 % of solids, including 0.13 % of pectin, 0.86 % of fat, 0.5 % of organic acids; 0.5 % minerals, etc. were used as a subject of research. These tomatoes, grown in the mountains, on soils with high salinity, contain high amounts of valuable components and have a long-term preservation. For the extraction of valuable components from dried tomato pomace CO2 extraction method was applied. Technological and environmental feasibility of tomatoes stage drying in the atmosphere of inert gas in solar dry kiln were evaluated; production scheme of dried tomatoes is improved; a system for tomato pomace drying is developed; a production scheme of powders of pulp, skin and seeds of tomatoes is developed. Combined method of tomato pomace drying involves the simultaneous use of the electromagnetic field of low and ultra-high frequency and blowing product surface with hot nitrogen. Conducting the drying process in an inert gas atmosphere of nitrogen intensified the process of moisture removing from tomatoes. The expediency of using tomato powder as enriching additive was proved. Based on the study of the chemical composition of the tomato powder made from Dagestan varieties of tomatoes, and on the organoleptic evaluation and physico-chemical studies of finished products, we have proved the best degree of recoverability of tomato powder during the production of reconstituted juice and tomato beverages.

  10. Polyhydroxyalcanoates of strains of Azospirillum spp. isolated of roots of Lycopersicon esculentum Mill. “tomato” and Oryza sativa L. “rice” in Lambayeque

    Directory of Open Access Journals (Sweden)

    Katty Baca

    2010-12-01

    Full Text Available In this work was determined the concentration of polyhydroxyalkanoates (PHAs of Azospirillum strains isolated from roots of Lycopersicon esculentum Mill "tomato" and Oryza sativa L. "rice" as an alternative to accumulation of petroleum-based plastics. Previously disinfected root were plated in Nfb semisolid medium where nitrogen-fixing bacteria were recognized by a whitish film on the surface and turn from green to blue. The genus Azospirillum was identified in Congo red agar medium, obtained 96 isolates of A. lipoferum and A. brasilense on tomato and rice. Batch fermentation was performed with broth Azotobacter modified feeding a saturated solution of malic acid every 12 hours and were stained with Sudan Black B. Strains were selected with the greatest number of PHAs granules (in tomato, 18 of A. lipoferum and 2 of A. brasilense; in rice, 10 of A. lipoferum and 10 of A. brasilense and quantified the biomass and PHAs. PHAs concentration reached 0.661 gL-1 in A. lipoferum KM(T-73 and 0.738 gL-1 in A. brasilense KM(T-19, both isolated from tomato. Strains of A. lipoferum and A. brasilense isolated from tomato reached a higher concentration of biomass and PHAs against the strains of rice.

  11. Photovoltaics for Buildings Cutting-Edge PV

    International Nuclear Information System (INIS)

    Hayter, S. J.; Martin, R. L.

    1998-01-01

    Photovoltaic (PV) technology development for building-integrated applications (commonly called PV for Buildings) is one of the fastest growing areas in the PV industry. Buildings represent a huge potential market for photovoltaics because they consume approximately two-thirds of the electricity consumed in the US. The PV and buildings industries are beginning to work together to address issues including building codes and standards, integration, after-market servicing, education, and building energy efficiency. One of the most notable programs to encourage development of new PV-for-buildings products is the PV:BONUS program, supported by the US Department of Energy. Demand for these products from building designers has escalated since the program was initiated in 1993. This paper presents a range of PV-for-buildings issues and products that are currently influencing today's PV and buildings markets

  12. Global PV Market Development

    International Nuclear Information System (INIS)

    Schmidt, F.

    2009-01-01

    The dawn of 2009 saw several events which caused major turbulence in the global photovoltaic industry. In 2008 the Spanish PV market grew beyond all expectations and even outranked Germany as the world's number one market. However, the promotion scheme was modified and a market cap was introduced in 2009, cutting back the maximum capacity to be installed to about the level of 2007. In addition, the industry is facing an oversupply of PV modules and a harsh recession which is significantly affecting the traditionally strong PV markets. International photovoltaic companies are challenged by a changing market situation: all of a sudden, competition has increased significantly, pushing the customer to the fore. As a result, a consolidation process is expected within the PV industry worldwide. However, the story is not all negative. In the U.S., the election of Barack Obama may be seen as the starting signal for a massive expansion in PV, likely to bring the country to first place globally within the next five years. Furthermore, different markets and market segments are being opened up - especially in Europe - thanks to the gradual arrival of generation parity and new PV support mechanisms. EuPD Research has observed and studied international PV markets since its foundation. The information included in the presentation is based on a wide range of quantitative and qualitative studies that EuPD Research has conducted in the key markets since 2002. Florian Schmidt, EuPD Research's Head of Product Management, will give an overview of the global PV market and how it is developing in this crucial year 2009. Aspects such as technology development, production capacities and the demand side will be included, with a special emphasis on the European PV markets. So far Chinese PV companies have often benefited from the booming PV markets in Europe, above all Germany and Spain. Due to the lack of domestic market, the Chinese industry strongly depends on the export and is

  13. Tomato Sauce Enriched with Olive Oil Exerts Greater Effects on Cardiovascular Disease Risk Factors than Raw Tomato and Tomato Sauce: A Randomized Trial

    Directory of Open Access Journals (Sweden)

    Palmira Valderas-Martinez

    2016-03-01

    Full Text Available Epidemiological studies have observed a negative association between tomato intake and the incidence of cardiovascular disease. As tomato sauces are usually cooked with the addition of oil, some studies have pointed out that both processes may increase the bioavailability of the bioactive compounds. However, the effect of consumption of raw tomatoes and tomato sauces on inflammation biomarkers and adhesion molecules related to atherosclerosis remains unknown. The aim of this study was to test the postprandial effects of a single dose of raw tomatoes (RT, tomato sauce (TS and tomato sauce with refined olive oil (TSOO on cardiovascular disease risk factors. We performed an open, prospective, randomized, cross-over, controlled feeding trial in 40 healthy subjects who randomly received: 7.0 g of RT/kg of body weight (BW, 3.5 g of TS/kg BW, 3.5 g of TSOO/Kg BW and 0.25 g of sugar solved in water/kg BW on a single occasion on four different days. Biochemical parameters and cellular and circulating inflammatory biomarkers were assessed at baseline and 6 h after each intervention. The results indicate that, compared to control intervention, a single tomato intake in any form decreased plasma total cholesterol, triglycerides and several cellular and plasma inflammatory biomarkers, and increased plasma high density lipoproteins (HDL cholesterol and interleukine (IL 10 concentrations. However, the changes of plasma IL-6 and vascular cell adhesion molecule-1 (VCAM-1, and lymphocyte function-associated antigen-1 (LFA-1 from T-lymphocytes and CD36 from monocytes were significantly greater after TSOO than after RT and TS interventions. We concluded that tomato intake has beneficial effects on cardiovascular risk factors, especially cooked and enriched with oil.

  14. Seleção de bactérias endofíticas de tomateiro como potenciais agentes de biocontrole e de promoção de crescimento Screening of endophytic bacteria isolated from tomato plants as potencial biocontrol agents and growth promotion

    Directory of Open Access Journals (Sweden)

    Patrícia Baston Barretti

    2009-01-01

    Full Text Available Quarenta isolados bacterianos endofíticos de plantas sadias de tomateiro foram avaliados quanto à sua potencialidade como agentes de biocontrole de doenças do tomateiro. Foi realizada, em casa de vegetação, uma seleção massal utilizando-se Pseudomonas syringae pv. tomato e Alternaria solani, como patógenos desafiantes. Com base na média do número de lesões por planta, quatro isolados foram selecionados como potenciais agentes de biocontrole dessas enfermidades fúngica e bacteriana do tomateiro. Esses isolados foram identificados, por meio do sequenciamento do gene 16S do DNA ribossômico, como Acinetobacter johnsonii (UFV-E05, Serratia marcescens (UFV-E13, Sinorhizobium sp. (UFV-E25 e Bacillus megaterium (UFV-E26. Os mesmos isolados selecionados para o biocontrole também foram avaliados quanto à sua capacidade de promover o crescimento em plantas e somente S. marcescens (UFV-E13 proporcionou aumento na altura das plantas.Forty isolates of endophytic bacteria obtained from healthy tomato plants were tested for their potential as biocontrol agents of tomato diseases. A massal screening was performed at greenhouse using Pseudomonas syringae pv. tomato and Alternaria solani as challenging pathogens. Based on the average number of lesions per plant, four isolates were selected as potential agents of biocontrol of these tomato diseases caused by fungi and bacteria. These isolates were identified by 16S ribosomal DNA sequence analysis as Acinetobacter johnsonii (UFV-E05, Serratia marcescens (UFV-E13, Sinorhizobium sp. (UFV-E25 and Bacillus megaterium (UFV-E26. The four endophytes selected for biocontrol were also evaluated for their ability of promoting plant growth and only S. marcescens (UFV-E13 presented increase in the height of the plants.

  15. Differential modulation of plant immune responses by diverse members of the Pseudomonas savastanoi pv. savastanoi HopAF type III effector family.

    Science.gov (United States)

    Castañeda-Ojeda, M Pilar; López-Solanilla, Emilia; Ramos, Cayo

    2017-06-01

    The Pseudomonas savastanoi pv. savastanoi NCPPB 3335 type III secretion system (T3SS) effector repertoire includes 33 candidates, seven of which translocate into host cells and interfere with plant defences. The present study was performed to investigate the co-existence of both plasmid- and chromosomal-encoded members of the HopAF effector family, HopAF1-1 and HopAF1-2, respectively, in the genome of NCPPB 3335. Here, we show that the HopAF1 paralogues are widely distributed in the Pseudomonas syringae complex, where HopAF1-1 is most similar to the homologues encoded by other P. syringae pathovars infecting woody hosts that belong to phylogroups 1 and 3. We show that the expression of both HopAF1-1 and HopAF-2 is transcriptionally dependent on HrpL and demonstrate their delivery into Nicotiana tabacum leaves. Although the heterologous delivery of either HopAF1-1 or HopAF1-2 significantly suppressed the production of defence-associated reactive oxygen species levels, only HopAF1-2 reduced the levels of callose deposition. Moreover, the expression of HopAF1-2 by functionally effectorless P. syringae pv. tomato DC3000D28E completely inhibited the hypersensitive response in tobacco and significantly increased the competitiveness of the strain in Nicotiana benthamiana. Despite their functional differences, subcellular localization studies reveal that green fluorescent protein (GFP) fusions to either HopAF1-1 or HopAF1-2 are targeted to the plasma membrane when they are expressed in plant cells, a process that is completely dependent on the integrity of their N-myristoylation motif. Our results further support the notion that highly similar T3SS effectors might differentially interact with diverse plant targets, even when they co-localize in the same cell compartment. © 2016 BSPP AND JOHN WILEY & SONS LTD.

  16. PV-hybrid and mini-grid

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-07-01

    Within the 5th European PV-hybrid and mini-grid conference 29th and 30th April, 2010 in Tarragona (Spain) the following lectures were held: (1) Overview of IEA PVPS Task 11 PV-hybrid systems within mini grids; (2) Photovoltaic revolution for deployment in developing countries; (3) Legal and financial conditions for the sustainable operation of mini-grids; (4) EU instruments to promote renewable energies in developing countries; (5) PV hybridization of diesel electricity generators: Conditions of profitability and examples in differential power and storage size ranges; (6) Education suit of designing PV hybrid systems; (7) Sustainable renewable energy projects for intelligent rural electrification in Laos, Cambodia and Vietnam; (8) Techno-economic feasibility of energy supply of remote villages in Palestine by PV systems, diesel generators and electric grid (Case studies: Emnazeil and Atouf villages); (9) Technical, economical and sustainability considerations of a solar PV mini grid as a tool for rural electrification in Uganda; (10) Can we rate inverters for rural electrification on the basis of energy efficiency?; (11) Test procedures for MPPT charge controllers characterization; (12) Energy storage for mini-grid stabilization; (13) Redox flow batteries - Already an alternative storage solution for hybrid PV mini-grids?; (14) Control methods for PV hybrid mini-grids; (15) Partial AC-coupling in mini-grids; (15) Normative issues of small wind turbines in PV hybrid systems; (16) Communication solutions for PV hybrid systems; (17) Towards flexible control and communication of mini-grids; (18) PV/methanol fuel cell hybrid system for powering a highway security variable message board; (19) Polygeneration smartgrids: A solution for the supply of electricity, potable water and hydrogen as fuel for transportation in remote Areas; (20) Implementation of the Bronsbergen micro grid using FACDS; (21) A revisited approach for the design of PV wind hybrid systems; (22

  17. SunShot 2030 for Photovoltaics (PV): Envisioning a Low-Cost PV Future

    Energy Technology Data Exchange (ETDEWEB)

    Cole, Wesley J [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Frew, Bethany A [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Gagnon, Pieter J [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Richards, James [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Sun, Yinong [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Zuboy, Jarrett; Woodhouse, Michael A [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Margolis, Robert M [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-10-01

    This presentation summarizes the findings from the report 'SunShot 2030 for Photovoltaics (PV): Envisioning a Low-cost PV Future.' This presentation was given as a webinar on September 26, 2017.

  18. Economic PV - a shift in thinking

    International Nuclear Information System (INIS)

    Maycock, P.

    1999-01-01

    This article argues that photovoltaic (PV) technology is already economically viable contrary to current opinion. A table of world PV module shipments for 1990 to 1998 by market sector is presented, and use of PV modules in consumer electronics such as calculators, battery trickle chargers, and garden lights; in communications and signals (eg. microwave repeaters, cellular communication); and in the residential sector in fluorescent lights, radios etc. are discussed. The early adopters of PV technology, and the value placed on PV devices by consumers are considered. Details of PV manufacturing costs for 1997, and forecasts for 2000 and 2010 are tabulated

  19. Anti-protozoal effects of the tomato tetrasaccharide glycoalkaloid tomatine and the aglycone tomatidine on mucosal trichomonads

    Science.gov (United States)

    The present study investigated the inhibitory effects of the commercial tetrasaccharide tomato glycoalkaloid tomatine and the aglycone tomatidine on three mucosal pathogenic protozoa that are reported to infect humans, cattle, and cats, respectively: Trichomonas vaginalis Strain G3, Tritrichomonas f...

  20. Effects of postharvest handling conditions on internalization and growth of Salmonella enterica in tomatoes.

    Science.gov (United States)

    Zhou, Bin; Luo, Yaguang; Nou, Xiangwu; Yang, Yang; Wu, Yunpeng; Wang, Qin

    2014-03-01

    Salmonella internalization in tomatoes during postharvest handling is a major food safety concern. This study was conducted to determine the effect of immersion time, immersion depth, and temperature differential between bacterial suspension and tomato pulp on the internalization of Salmonella enterica in tomato fruits. The effect of storage temperature and duration on the survival and growth of internalized Salmonella cells was also evaluated. Overall, immersion time significantly affected the incidence and extent of S. enterica internalization (P internalization. The depth of Salmonella internalization in tomato tissues also increased with increasing immersion time. Immersion time also significantly influenced the degree to which the temperature differential affected Salmonella internalization. With an immersion time of 2 min, the temperature differential had no significant effect on Salmonella internalization (P = 0.2536). However, with an immersion time of 15 min, a significantly larger Salmonella population became internalized in tomatoes immersed in solutions with a -30°F (-16.7°C) temperature differential. Internalized S. enterica cells persisted in the core tissues during 14 days of storage. Strain type and storage duration significantly affected (P internalized Salmonella recovered, but storage temperatures of 55 to 70°F (12.8 to 21.1°C) did not (P > 0.05). These findings indicate the importance of preventing pathogen internalization during postharvest handling.

  1. Host-Induced Silencing of Pathogenicity Genes Enhances Resistance to Fusarium oxysporum Wilt in Tomato.

    Science.gov (United States)

    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.

  2. The stealth episome: suppression of gene expression on the excised genomic island PPHGI-1 from Pseudomonas syringae pv. phaseolicola.

    Directory of Open Access Journals (Sweden)

    Scott A C Godfrey

    2011-03-01

    Full Text Available Pseudomonas syringae pv. phaseolicola is the causative agent of halo blight in the common bean, Phaseolus vulgaris. P. syringae pv. phaseolicola race 4 strain 1302A contains the avirulence gene avrPphB (syn. hopAR1, which resides on PPHGI-1, a 106 kb genomic island. Loss of PPHGI-1 from P. syringae pv. phaseolicola 1302A following exposure to the hypersensitive resistance response (HR leads to the evolution of strains with altered virulence. Here we have used fluorescent protein reporter systems to gain insight into the mobility of PPHGI-1. Confocal imaging of dual-labelled P. syringae pv. phaseolicola 1302A strain, F532 (dsRFP in chromosome and eGFP in PPHGI-1, revealed loss of PPHGI-1::eGFP encoded fluorescence during plant infection and when grown in vitro on extracted leaf apoplastic fluids. Fluorescence-activated cell sorting (FACS of fluorescent and non-fluorescent PPHGI-1::eGFP F532 populations showed that cells lost fluorescence not only when the GI was deleted, but also when it had excised and was present as a circular episome. In addition to reduced expression of eGFP, quantitative PCR on sub-populations separated by FACS showed that transcription of other genes on PPHGI-1 (avrPphB and xerC was also greatly reduced in F532 cells harbouring the excised PPHGI-1::eGFP episome. Our results show how virulence determinants located on mobile pathogenicity islands may be hidden from detection by host surveillance systems through the suppression of gene expression in the episomal state.

  3. Predicting the presence of whiteflies and tomato yellow leaf curl virus in Florida tomato fields

    Science.gov (United States)

    Florida is one of the leading states for production of fresh market tomatoes. Production is severely affected by Tomato yellow leaf curl virus (TYLCV). The objective of this study was to identify landscape and climatic factors that drive whitefly populations and TYLCV incidence in commercial tomato ...

  4. Tomato juices and tomato juice concentrates : a study of factors contributing to their gross viscosity

    NARCIS (Netherlands)

    Heutink, R.

    1986-01-01

    The gross viscosity of tomato juice and tomato juice concentrates was found to be determined primarily by the water insoluble solids (WIS) content. The serum viscosity did not contribute to gross viscosity. The WIS consisted of whole tomato cells, vascular bundles and skin fragments. In general the

  5. Effects of tomato variety, temperature differential and post-stem removal time on internalization of Salmonella Thompson into tomatoes

    Science.gov (United States)

    Tomatoes have been implicated in several Salmonellosis outbreaks due to possible contamination through bacterial infiltration into tomatoes during post-harvest handling. The aim of this study was to determine the effects of tomato variety, dump tank water to tomato pulp temperature differential, and...

  6. PV module mounting method and mounting assembly

    Science.gov (United States)

    Lenox, Carl J.S.; Johnson, Kurt M.

    2013-04-23

    A method for mounting PV modules to a deck includes selecting PV module layout pattern so that adjacent PV module edges are spaced apart. PV mounting and support assemblies are secured to the deck according to the layout pattern using fasteners extending into the deck. The PV modules are placed on the PV mounting and support assemblies. Retaining elements are located over and secured against the upper peripheral edge surfaces of the PV modules so to secure them to the deck with the peripheral edges of the PV modules spaced apart from the deck. In some examples a PV module mounting assembly, for use on a shingled deck, comprises flashing, a base mountable on the flashing, a deck-penetrating fastener engageable with the base and securable to the deck so to secure the flashing and the base to the shingled deck, and PV module mounting hardware securable to the base.

  7. Irrigation water quality and the benefits of implementing good agricultural practices during tomato (Lycopersicum esculentum) production.

    Science.gov (United States)

    Estrada-Acosta, M; Jiménez, M; Chaidez, C; León-Félix, J; Castro-Del Campo, N

    2014-07-01

    The implementation of good agricultural practices (GAP) from irrigation water to the tomato packaging process enhances the safety of fresh produce and its value throughout the food chain. The aim of the present study was to show that fresh produce farms that apply and enforce GAP could reduce the presence of Salmonella in finished produce. Samples were collected biweekly from six packing houses from the central region of Sinaloa, México, for the isolation of Salmonella spp by the ISO 6579:2002 method, and the isolated strains were serotyped and genotyped by the Kauffmman-White scheme and pulsed field gel electrophoresis (PFGE), respectively. Salmonella strains were detected in 13 (36.1 %) irrigation water samples, while only two tomato samples were positive (5.5 %). Eight different serotypes were identified in irrigation water, and Salmonella Oranienburg (34 %) was the most prevalent; however, only Salmonella Agona and Salmonella Weltevreden were present on tomatoes. Salmonella Oranienburg was the most widely dispersed and variable serotype, with 10 different PFGE profiles. Salmonella Weltevreden was isolated from both types of samples, albeit with distinct genetic profiles, implying that the sources of contamination differ. These results confirm the utility of implementing good agricultural practices to reduce Salmonella contamination in irrigation water and the packaging process.

  8. Effects of Tomato Root Exudates on Meloidogyne incognita.

    Directory of Open Access Journals (Sweden)

    Guodong Yang

    Full Text Available Plant root exudates affect root-knot nematodes egg hatch. Chemicals in root exudates can attract nematodes to the roots or result in repellence, motility inhibition or even death. However, until recently little was known about the relationship between tomato root exudates chemicals and root-knot nematodes. In this study, root exudates were extracted from three tomato rootstocks with varying levels of nematode resistance: Baliya (highly resistant, HR, RS2 (moderately resistant, MR and L-402 (highly susceptible, T. The effects of the root exudates on Meloidogyne incognita (M. incognita egg hatch, survival and chemotaxis of second-stage juveniles (J2 were explored. The composition of the root exudates was analysed by gas chromatography/mass spectrometry (GC/MS prior to and following M. incognita inoculation. Four compounds in root exudates were selected for further analysis and their allopathic effect on M. incognita were investigated. Root exudates from each tomato rootstocks (HR, MR and T strains suppressed M. incognita egg hatch and increased J2 mortality, with the highest rate being observed in the exudates from the HR plants. Exudate from HR variety also repelled M. incognita J2 while that of the susceptible plant, T, was demonstrated to be attractive. The relative amount of esters and phenol compounds in root exudates from HR and MR tomato rootstocks increased notably after inoculation. Four compounds, 2,6-Di-tert-butyl-p-cresol, L-ascorbyl 2,6-dipalmitate, dibutyl phthalate and dimethyl phthalate increased significantly after inoculation. The egg hatch of M. incognita was suppressed by each of the compound. L-ascorbyl 2,6-dipalmitate showed the most notable effect in a concentration-dependent manner. All four compounds were associated with increased J2 mortality. The greatest effect was observed with dimethyl phthalate at 2 mmol·L-1. Dibutyl phthalate was the only compound observed to repel M. incognita J2 with no effect being detected in

  9. Numerical study of PV/T-SAHP system

    Institute of Scientific and Technical Information of China (English)

    Gang PEI; Jie JI; Ke-liang LIU; Han-feng HE; Ai-guo JIANG

    2008-01-01

    In order to utilize solar energy effectively and to achieve a higher electrical efficiency by limiting the operating temperature of the photovoltaic (PV) panel, a novel photovoltaic/thermal solar-assisted heat pump (PV/T-SAHP) system was proposed and constructed. The hybrid solar system generates electricity and thermal energy simultaneously. A distributed parameters model of the PV/T-SAHP system was developed and applied to analyze the system dynamic performance in terms of PV action, photothermal action and Rankine cycle processes. The simulation results indicated that the coefficient of performance (COP) of the proposed PV/T-SAHP can be much better than that of the conventional heat pump. Both PV-efficiency and photothermic efficiency have been improved considerably. The results also showed that the performance of this PV/T-SAHP system was strongly influenced by the evaporator area, tube pitch and tilt angle of the PV/T evaporator, which are the key factors in PV/T-SAHP system optimization and PV/T evaporator design.

  10. Advanced Copper Composites Against Copper-Tolerant Xanthomonas perforans and Tomato Bacterial Spot.

    Science.gov (United States)

    Strayer-Scherer, A; Liao, Y Y; Young, M; Ritchie, L; Vallad, G E; Santra, S; Freeman, J H; Clark, D; Jones, J B; Paret, M L

    2018-02-01

    Bacterial spot, caused by Xanthomonas spp., is a widespread and damaging bacterial disease of tomato (Solanum lycopersicum). For disease management, growers rely on copper bactericides, which are often ineffective due to the presence of copper-tolerant Xanthomonas strains. This study evaluated the antibacterial activity of the new copper composites core-shell copper (CS-Cu), multivalent copper (MV-Cu), and fixed quaternary ammonium copper (FQ-Cu) as potential alternatives to commercially available micron-sized copper bactericides for controlling copper-tolerant Xanthomonas perforans. In vitro, metallic copper from CS-Cu and FQ-Cu at 100 μg/ml killed the copper-tolerant X. perforans strain within 1 h of exposure. In contrast, none of the micron-sized copper rates (100 to 1,000 μg/ml) from Kocide 3000 significantly reduced copper-tolerant X. perforans populations after 48 h of exposure compared with the water control (P copper-based treatments killed the copper-sensitive X. perforans strain within 1 h. Greenhouse studies demonstrated that all copper composites significantly reduced bacterial spot disease severity when compared with copper-mancozeb and water controls (P copper composites significantly reduced disease severity when compared with water controls, using 80% less metallic copper in comparison with copper-mancozeb in field studies (P copper composites have the potential to manage copper-tolerant X. perforans and tomato bacterial spot.

  11. [Controlling effect of antagonist bioorganic fertilizer on tomato root-knot nematode].

    Science.gov (United States)

    Zhu, Zhen; Chen, Fang; Xiao, Tong-jian; Wang, Xiao-hui; Ran, Wei; Yang, Xing-ming; Shen, Qi-rong

    2011-04-01

    Indoor in vitro culture experiment and greenhouse pot experiment were conducted to evaluate the capabilities of three bacterial strains XZ-173 (Bacillus amyloliquefaciens), SL-25 (B. gibsonii), and KS-62 (Paenibacillus polymyxa) that can hydrolyze collagen protein in controlling tomato root-knot nematode. In the in vitro culture experiment, suspensions of XZ-173, SL-25, and KS-62 induced a mortality rate of 75.9%, 66.7%, and 50.0% to the second-stage junior nematode within 24 h, and decreased the egg hatching rate to 17.8%, 28.9% and 37.6% after 7-day incubation, respectively, in contrast to the 17.4% mortality rate and 53.6% egg hatching rate in the control (sterilized water). In the greenhouse pot experiment, the bioorganic fertilizer mixed with equal parts of fermented XZ-173, SL-25, and KS-62 gained the best result, with the root-knot nematode population in rhizosphere soil decreased by 84.0% as compared with the control. The bioorganic fertilizer also decreased the numbers of galls and eggs on tomato roots significantly, and increased the underground and aboveground biomass of tomato. Therefore, antagonist bioorganic fertilizer has promising potential in controlling root-knot nematode.

  12. Design optimization of grid-connected PV inverters

    DEFF Research Database (Denmark)

    Koutroulis, Eftichios; Blaabjerg, Frede

    2011-01-01

    The DC/AC inverters are the key elements in grid-connected PV energy production systems. In this paper, new design optimization techniques focused on transformerless (very high efficiency) PV inverters are proposed. They have been developed based on an analysis of the deficiencies of the current......, state-of-the-art PV inverters design technology, which limits the amount of PV energy supplied into the electric grid. The influences of the electric grid regulations and standards and the PV array operational characteristics on the design of grid-connected PV inverters have also been considered....... The simulation results verify that the proposed optimization techniques enable the maximization of the PV energy injected into the electric grid by the optimized PV installation....

  13. A case study of utility PV economics

    International Nuclear Information System (INIS)

    Wenger, H.; Hoff, T.; Osborn, D.E.

    1997-01-01

    This paper presents selected results from a detailed study of grid-connected photovoltaic (PV) applications within the service area of the Sacramento Municipal Utility District. The intent is to better understand the economics and markets for grid-connected PV systems in a utility setting. Research results include: Benefits calculations for utility-owned PV systems at transmission and distribution voltages; How the QuickScreen software package can help utilities investigate the viability of distributed PV; Energy production and capacity credit estimates for fixed and tracking PV systems; Economics and rate impacts of net metering residential PV systems; Market potential estimates for residential rooftop PV systems; and Viability and timing of grid-connected PV commercialization paths

  14. Mechanism of action and in vitro activity of short hybrid antimicrobial peptide PV3 against Pseudomonas aeruginosa

    International Nuclear Information System (INIS)

    Memariani, Hamed; Shahbazzadeh, Delavar; Sabatier, Jean-Marc; Memariani, Mojtaba; Karbalaeimahdi, Ali; Bagheri, Kamran Pooshang

    2016-01-01

    Antimicrobial peptides are attractive candidates for developing novel therapeutic agents, since they are lethal to a broad spectrum of pathogens and have a unique low tendency for resistance development. In this study, mechanism of action and in vitro anti-pseudomonal activity of previously designed short hybrid antimicrobial peptide PV3 were investigated. Compared to ceftazidime, PV3 had not only higher antibacterial activity but also faster bactericidal activity. PV3 reduced biofilm biomass and viability of biofilm embedded bacteria in a concentration-dependent manner. Although the antimicrobial activity of PV3 was reduced in Mueller-Hinton broth (MHB) containing human serum, it was still active enough to eradication of bacteria at low concentrations. Compared with standard condition (MHB only), there was no significant decrease in antibacterial activity of PV3 against P. aeruginosa strains under 150 mM NaCl (p = 0.615) and 1 mM MgCl 2 (p = 0.3466). Fluorescence microscopy and field emission scanning electron microscopy further indicated that PV3 killed bacteria by disrupting the cell membrane. Since PV3 has potent anti-pseudomonal activity and has little cytotoxicity in vitro, it seems plausible that the peptide should be further investigated with animal studies to support future pharmacological formulations and potential topical applications. - Highlights: • PV3 killed Pseudomonas aeruginosa by membrane-disrupting mechanism. • PV3 reduced biofilm biomass and viability of biofilm embedded bacteria in a concentration-dependent manner. • Short hybrid antimicrobial peptide PV3 exhibited higher and faster bactericidal activity comparing to ceftazidime.

  15. Solar PV. Innovators talking; Zon PV. Innovators aan het woord

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-02-15

    Qualitative studies have been conducted of the results of completed projects focused on energy innovation, spread over the seven themes of the top sector Energy: Energy saving in industry, Energy conservation in the built environment, Gas, Bio-energy, Smart grids, Offshore Wind, Solar PV. This provides insight into the follow-up activities and lessons of some EOS (Energy Research Subsidy) completed projects with the aim to inspire, connect and strengthen the TKIs (Topconsortia for Knowledge and Innovation) and individual companies and researchers working on energy innovation. This report concerns the research on solar PV [Dutch] Er is een kwalitatief onderzoek uitgevoerd naar de resultaten van afgeronde projecten gericht op energie-innovatie, verdeeld over de zeven thema's van de topsector Energie: Energiebesparing in de industrie; Energiebesparing in de gebouwde omgeving; Gas; Bio-energie; Smart grids; Wind op zee; Zon-pv. Daarmee wordt inzicht gegeven in de vervolgactiviteiten en lessen van een aantal afgesloten EOS-projecten (Energie Onderzoek Subsidie) met het oog op het inspireren, verbinden en versterken van de TKI's (Topconsortia voor Kennis en Innovatie) en individuele bedrijven en onderzoekers die werken aan energie-innovatie. Dit rapport betreft het onderzoek naar zon PV.

  16. Solar PV. Innovators talking; Zon PV. Innovators aan het woord

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-02-15

    Qualitative studies have been conducted of the results of completed projects focused on energy innovation, spread over the seven themes of the top sector Energy: Energy saving in industry, Energy conservation in the built environment, Gas, Bio-energy, Smart grids, Offshore Wind, Solar PV. This provides insight into the follow-up activities and lessons of some EOS (Energy Research Subsidy) completed projects with the aim to inspire, connect and strengthen the TKIs (Topconsortia for Knowledge and Innovation) and individual companies and researchers working on energy innovation. This report concerns the research on solar PV [Dutch] Er is een kwalitatief onderzoek uitgevoerd naar de resultaten van afgeronde projecten gericht op energie-innovatie, verdeeld over de zeven thema's van de topsector Energie: Energiebesparing in de industrie; Energiebesparing in de gebouwde omgeving; Gas; Bio-energie; Smart grids; Wind op zee; Zon-pv. Daarmee wordt inzicht gegeven in de vervolgactiviteiten en lessen van een aantal afgesloten EOS-projecten (Energie Onderzoek Subsidie) met het oog op het inspireren, verbinden en versterken van de TKI's (Topconsortia voor Kennis en Innovatie) en individuele bedrijven en onderzoekers die werken aan energie-innovatie. Dit rapport betreft het onderzoek naar zon PV.

  17. Firefighter Safety for PV Systems

    DEFF Research Database (Denmark)

    Mathe, Laszlo; Sera, Dezso; Spataru, Sergiu

    2015-01-01

    An important and highly discussed safety issue for photovoltaic (PV) systems is that as long as the PV panels are illuminated, a high voltage is present at the PV string terminals and cables between the string and inverters that is independent of the state of the inverter's dc disconnection switch...

  18. Grid integrated distributed PV (GridPV).

    Energy Technology Data Exchange (ETDEWEB)

    Reno, Matthew J.; Coogan, Kyle

    2013-08-01

    This manual provides the documentation of the MATLAB toolbox of functions for using OpenDSS to simulate the impact of solar energy on the distribution system. The majority of the functions are useful for interfacing OpenDSS and MATLAB, and they are of generic use for commanding OpenDSS from MATLAB and retrieving information from simulations. A set of functions is also included for modeling PV plant output and setting up the PV plant in the OpenDSS simulation. The toolbox contains functions for modeling the OpenDSS distribution feeder on satellite images with GPS coordinates. Finally, example simulations functions are included to show potential uses of the toolbox functions. Each function in the toolbox is documented with the function use syntax, full description, function input list, function output list, example use, and example output.

  19. PV/T slates - Pilot project in Steinhausen; PV/T-Schiefer. Pilotprojekt Steinhausen

    Energy Technology Data Exchange (ETDEWEB)

    Kropf, S.

    2003-07-01

    This comprehensive, illustrated report for the Swiss Federal Office of Energy (SFOE) is one a series of five reports dealing with increasing the overall efficiency of photovoltaic (PV) installations by also using the heat collected by the dark-coloured PV panels. The work reported on addresses open questions on the use of the heat and its optimal use. This report deals with a ventilated PV-tile system (PV/T-Slates) mounted on a garden shed in Steinhausen, Switzerland. The installation provides power and heat to the main house. The report describes the construction and operation of this pilot project and the results of measurements made on its electrical and thermal performance. The results of measurements made are presented in detail in graphical form and compared with the results of simulation. Suggestions are made for the optimisation of the system. Figures are presented on energy production and energy flows in graphical form.

  20. The Epl1 and Sm1 proteins from Trichoderma atroviride and Trichoderma virens differentially modulate systemic disease resistance against different life style pathogens in Solanum lycopersicum

    Directory of Open Access Journals (Sweden)

    Miguel Angel eSalas-Marina

    2015-02-01

    Full Text Available Fungi belonging to the genus Trichoderma, commonly found in soil or colonizing plant roots, exert beneficial effects on plants, including the promotion of growth and the induction of resistance to disease. T. virens and T. atroviride secrete the proteins Sm1 and Epl1, respectively, which elicit local and systemic disease resistance in plants. In this work, we show that these fungi promote growth in tomato (Solanum lycopersicum plants. T. virens was more effective than T. atroviride in promoting biomass gain, and both fungi were capable of inducing systemic protection in tomato against Alternaria solani, Botrytis cinerea, and Pseudomonas syringae pv. tomato (Pst DC3000. Deletion (KO of epl1 in T. atroviride resulted in diminished systemic protection against A. solani and B. cinerea, whereas the T. virens sm1 KO strain was less effective in protecting tomato against Pst DC3000 and B. cinerea. Importantly, over-expression (OE of epl1 and sm1 led to an increase in disease resistance against all tested pathogens. Although the Trichoderma WT strains induced both systemic acquired resistance (SAR- and induced systemic resistance (ISR-related genes in tomato, inoculation of plants with OE and KO strains revealed that Epl1 and Sm1 play a minor role in the induction of these genes. However, we found that Epl1 and Sm1 induce the expression of a peroxidase and an α-dioxygenase encoding genes, respectively, which could be important for tomato protection by Trichoderma spp. Altogether, these observations indicate that colonization by beneficial and/or infection by pathogenic microorganisms dictates many of the outcomes in plants, which are more complex than previously thought.

  1. Photovoltaics: PV takes off the UK

    International Nuclear Information System (INIS)

    Noble, Ray; Gregory, Jenny

    2000-01-01

    Despite historical ups and downs, there is still ambition to bring increasingly efficient photovoltaic (PV) systems to the market. PV for major remote telecommunications systems is now an established part of the market, many mobile phone systems are powered by PV and there is potential for increased use of home solar systems, especially in developing countries. Over the past few years, building-integrated PV (BIPV) has been on the increase. In 1999, global production from PV exceeded 200 MW and the UK installed capacity was greater than 1 MW. BIPV is a fast growing market and its characteristics and advantages are discussed. PV installations at Nottingham University, Greenwich Pavilion, BP Amoco Sunbury, Baglan Bay, BP filling stations, and Sainsbury's are described

  2. INTEGRATED WEED MANAGEMENT ON THE PROCESSING TOMATO CROP AND TOMATO FOR CONSUMPTION IN NATURA

    Directory of Open Access Journals (Sweden)

    Y. O. Castro

    2016-11-01

    Full Text Available Weeds cause direct and indirect damage to processing tomato and tomato for consumption in natura. The coexistence period is decisive for the intensity of damage, although the economic cost is also considered for decision making when to control the weeds. There are similarities between processing tomato and tomato for consumption in natura cropping system and peculiarities. This causes the management has adopted its common applications and its variables within each system. As control alternative, the farmer has basically the preventive control, mechanical, cultural, biological and chemical. The application of a single method is not recommended. Ideally, the methods needs to be integrated in order to combat weeds, highly evolved populations and resistant to unfavorable conditions. Consider weed management taking only one control measure is to underestimate the evolutionary ability of such species. Therefore, it is necessary to integrate the various methods available to the weed interference not impede the tomato production.

  3. Tomato fruit and seed colonization by Clavibacter michiganensis subsp. michiganensis through external and internal routes.

    Science.gov (United States)

    Tancos, Matthew A; Chalupowicz, Laura; Barash, Isaac; Manulis-Sasson, Shulamit; Smart, Christine D

    2013-11-01

    The Gram-positive bacterium Clavibacter michiganensis subsp. michiganensis, causal agent of bacterial wilt and canker of tomato, is an economically devastating pathogen that inflicts considerable damage throughout all major tomato-producing regions. Annual outbreaks continue to occur in New York, where C. michiganensis subsp. michiganensis spreads via infected transplants, trellising stakes, tools, and/or soil. Globally, new outbreaks can be accompanied by the introduction of contaminated seed stock; however, the route of seed infection, especially the role of fruit lesions, remains undefined. In order to investigate the modes of seed infection, New York C. michiganensis subsp. michiganensis field strains were stably transformed with a gene encoding enhanced green fluorescent protein (eGFP). A constitutively eGFP-expressing virulent C. michiganensis subsp. michiganensis isolate, GCMM-22, was used to demonstrate that C. michiganensis subsp. michiganensis could not only access seeds systemically through the xylem but also externally through tomato fruit lesions, which harbored high intra- and intercellular populations. Active movement and expansion of bacteria into the fruit mesocarp and nearby xylem vessels followed, once the fruits began to ripen. These results highlight the ability of C. michiganensis subsp. michiganensis to invade tomato fruits and seeds through multiple entry routes.

  4. [Effects of interaction between vermicompost and probiotics on soil nronerty, yield and quality of tomato].

    Science.gov (United States)

    Shen, Fei; Zhu, Tong-bin; Teng, Ming-jiao; Chen, Yue; Liu, Man-qiang; Hu, Feng; Li, Hui-xin

    2016-02-01

    In this study, we investigated the effects of two strains of probiotic bacteria (Bacillus megaterium BM and Bacillus amyloliquefaciens BA) combined with chemical fertilizers and vermicompost on the soil property, the yield and quality of tomato. The results showed that under the same nutrient level, vermicompost significantly increased the yield, soluble sugar and protein contents of fruit, the soil pH and available phosphorus when compared with chemical fertilizers. Vermicompost combined with probiotics not only increased the tomato yield, soluble sugar, protein and vitamin C contents, sugar/acid ratio of fruit, and reduced the organic acid and nitrate nitrogen contents of fruit, also increased the soil pH and nitrate nitrogen content, and reduced soil electric conductivity when compared with vermicompost treatment. This improved efficiency was better than that by chemical fertilizers combined with probiotics. For BA and BM applied with chemical fertilizers or vermicompost, both stains had no significant effect on tomato quality. When co-applied with vermicompost, BA and BM showed significant difference in tomato yield. High soil available phosphorus content was determined when BM was combined with chemical fertilizers, while high soil available potassium content was obtained when BA was combined with vermicompost. Our results suggested that probiotics and vermicompost could be used as alternatives of chemical fertilizers in tomato production and soil fertility improvement.

  5. Competitiveness of tomato production in punjab, pakistan

    International Nuclear Information System (INIS)

    Akhtar, W.; Qureshi, A.H.; Khan, M.A.

    2016-01-01

    The study measures competitiveness at farm level and economic efficiency at country level of tomato production in relation to tomato trade by using Policy Analysis Matrix (PAM) framework in Punjab, Pakistan. The province was divided into two tomato production regions i.e., Central and Southern Punjab for analysis purpose under importable scenario by using import parity price. Results of PAM model revealed that tomato production in both regions of Punjab has competitiveness under prevailing market situation as indicated by positive private profitability and private cost ratio (PCR) which is less than 1. Competitiveness difference in two regions indicated that Central Punjab has more competitiveness at farm level in tomato production. Economic efficiency results i.e. Domestic Resource Cost (DRC) ratio remained 0.39 and 0.51 in Central and Southern Punjab, respectively with positive social profitability indicating strong comparative advantage under importable scenario. The above results implied that Central Punjab has greater economic efficiency than Southern Punjab in domestic resources use for production of tomato as import substitute commodity. Results of Nominal Protection Coefficient (NPC) and Effective Protection Coefficient (EPC) indicated that combine effects of policies on output and tradable input market did not pass any protection to tomato farmers in the study area. Net effect of policy or market failure is reducing the profitability of tomato producers at farm level which indicates lack of motivation from policies for farmers to expand tomato production as import substitute crop. Present study recommended competitiveness and economic efficiency analysis in other tomato producing regions of the country for year round tomato supply on the basis of resource efficiency and to curtail tomato imports to save the precious foreign exchange. To enhance the competitiveness there is need to increase farmer's incentives through increase of farm level price up to

  6. PV-BUK: Operating and maintenance costs of photovoltaic installations; PV-BUK - Betriebs- und Unterhaltskosten von PV-Anlagen - Schlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Stettler, S.; Toggweiler, P. [Enecolo AG, Moenchaltorf (Switzerland); Ruoss, D.; Schudel, P. [Envision, Lucerne (Switzerland); Kottmann, A.; Steinle, F. [BE Netz AG, Lucerne (Switzerland)

    2008-03-15

    This final report elaborated for the Swiss Federal Office of Energy (SFOE) takes a look at the results of a project carried out to determine the costs for facility management, to estimate future cost development and to propose activities for the further reduction of the operation and maintenance costs of photovoltaic systems. Information on the cost situation was collected by literature study, as well as in interviews and surveys with photovoltaic (PV) experts and the owners of PV installations. The discussion of the results at a workshop with about 20 Swiss PV experts is noted. The results are presented and discussed. These show that operating costs per kWh decrease with the size of the PV system. Figures are quoted. The major part of the costs are quoted as being those for spare parts, especially for the inverter. The authors are of the opinion that, in future, costs for facility management will further decrease, as they are partly linked to capital and insurance costs. Potential for optimisation is said to exist in several areas of facility management such as, for example, in system monitoring and fast reaction in the case of malfunctions.

  7. Gamma-irradiation of tomatoes

    International Nuclear Information System (INIS)

    Tencheva, S.; Todorov, S.

    1975-01-01

    The influence of gamma-ray on tomatoes picked in a pink-red ripening stage, good for consumption, is studied. For that purpose tomatoes of ''Pioneer 2'' variety packed in perforated 500 g plastic bags were irradiated on a gamma device (Cobalt-60) at a dose power of 1900 rad/min with doses 200 or 300 krad. Samples were stored after irradiation at room temperature (20 - 22sup(o)C). Microbiological studies demonstrated that 44 resp. 99.96 per cent of the initial number of microorganisms was destroyed after irradiation with 200 resp. 300 krad. The time required for the number of microorganisms to be restored was accordingly increased. Irradiation delayed tomato ripening by 4 to 6 days, demonstrable by the reduced content of the basic staining substances - carotene and licopine. Immediately after irradiation the ascorbic acid content was reduced by an average of 13 per cent. After 18 days the amount of ascorbic acid in irradiated tomatoes was increased to a higher than the starting level, this is attributed to reductone formation during irradiation. The elevated total sugar content shown to be invert sugar was due to further tomato ripening. (Ch.K.)

  8. Vibrio vulnificus phage PV94 is closely related to temperate phages of V. cholerae and other Vibrio species.

    Directory of Open Access Journals (Sweden)

    Mark Pryshliak

    Full Text Available BACKGROUND: Vibrio vulnificus is an important pathogen which can cause serious infections in humans. Yet, there is limited knowledge on its virulence factors and the question whether temperate phages might be involved in pathogenicity, as is the case with V. cholerae. Thus far, only two phages (SSP002 and VvAW1 infecting V. vulnificus have been genetically characterized. These phages were isolated from the environment and are not related to Vibrio cholerae phages. The lack of information on temperate V. vulnificus phages prompted us to isolate those phages from lysogenic strains and to compare them with phages of other Vibrio species. RESULTS: In this study the temperate phage PV94 was isolated from a V. vulnificus biotype 1 strain by mitomycin C induction. PV94 is a myovirus whose genome is a linear double-stranded DNA of 33,828 bp with 5'-protruding ends. Sequence analysis of PV94 revealed a modular organization of the genome. The left half of the genome comprising the immunity region and genes for the integrase, terminase and replication proteins shows similarites to V. cholerae kappa phages whereas the right half containing genes for structural proteins is closely related to a prophage residing in V. furnissii NCTC 11218. CONCLUSION: We present the first genomic sequence of a temperate phage isolated from a human V. vulnificus isolate. The sequence analysis of the PV94 genome demonstrates the wide distribution of closely related prophages in various Vibrio species. Moreover, the mosaicism of the PV94 genome indicates a high degree of horizontal genetic exchange within the genus Vibrio, by which V. vulnificus might acquire virulence-associated genes from other species.

  9. Nutritional evaluation of dried tomato seeds.

    Science.gov (United States)

    Persia, M E; Parsons, C M; Schang, M; Azcona, J

    2003-01-01

    Two samples of tomato seeds, a by-product of the tomato canning industry were evaluated to determine proximate analysis, amino acid content, and digestibility, TMEn, and protein efficiency ratio. Tomato seeds were also used to replace corn and soybean meal (SBM) in a chick diet on an equal true amino acid digestibility and TMEn basis. Tomato seeds were found to contain 8.5% moisture, 25% CP, 20.0% fat, 3.1% ash, 35.1% total dietary fiber, 0.12% Ca, 0.58% P, and 3,204 kcal/kg of TMEn. The total amounts of methionine, cystine, and lysine in the tomato seeds were 0.39, 0.40, and 1.34%, respectively, and their true digestibility coefficients, determined in cecectomized roosters, were 75, 70, and 54%, respectively. The protein efficiency ratio (weight gain per unit of protein intake) value when fed to chicks at 9% CP was 2.5 compared to 3.6 for SBM (P seeds could replace corn and SBM without any adverse affects on chick weight gain, feed intake, or gain:feed ratio from 8 to 21 d posthatch. Tomato seeds at any level in the diet did not significantly affect skin pigmentation. Although the protein quality of tomato seeds may not be as high as SBM, tomato seeds do contain substantial amounts of digestible amino acids and TMEn. When formulating diets on a true digestible amino acid and TMEn basis, tomato seeds can be supplemented into chick rations at up to 15% without any adverse affects on growth performance.

  10. Optimization of PV-based energy production by dynamic PV-panel/inverter configuration

    DEFF Research Database (Denmark)

    Paasch, Kasper; Nymand, Morten; Haase, Frerk

    This paper investigates the possible increase in annual energy production of a PV system with more than one MPPT (maximum power point tracker) input channels under Nordic illumination conditions, in case a concept of dynamic switching of the PV panels is used at the inputs of the inverters....

  11. PV integration into a CSP plant

    Science.gov (United States)

    Carvajal, Javier López; Barea, Jose M.; Barragan, Jose; Ortega, Carlos

    2017-06-01

    This paper describes a preliminary techno-economic analysis of the integration of a PV plant into an optimized Parabolic Trough Plant in order to reduce the online consumptions and thus, increase the net electricity injected into the grid. The idea is to assess the feasibility of such project and see what configuration would be the optimal. An extra effort has been made in terms of modelling as the analysis has to be done to the integrated CSP + PV plant instead of analyzing them independently. Two different technologies have been considered for the PV plant, fix and one-axis tracking. Additionally three different scenarios have been considered for the CSP plant auxiliary consumptions as they are essential for determining the optimal PV plant (the higher the auxiliary consumption the higher the optimal PV plant). As could be expected, the results for all cases with PV show an improvement in terms of electricity generation and also in terms of LCOE with respect to the CSP plant. Such improvement is slightly higher with tracking technology for this specific study. Although this exercise has been done to an already designed CSP plant (so only the PV plant had to be optimized), the methodology could be applied for the optimization of an integrated CSP + PV plant during the design phase.

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    Ma Hao

    2011-10-01

    Full Text Available Abstract 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.

  14. Managing thrips and tospoviruses in tomato

    Science.gov (United States)

    Tomato spotted wilt virus and more recently emerged Tomato chlorotic spot virus and Groundnut ringspot virus are all transmitted by thrips, making managment complex. All three viruses and the thrips vector are major pests of tomato in Florida. Current management tools for these viruses and the th...

  15. Projecting of PV facades in consideration of PV-specific operating conditions; Besonderheiten bei der Projektierung von Photovoltaik-Fassadenanlagen

    Energy Technology Data Exchange (ETDEWEB)

    Decker, B.; Grimmig, B.; Mencke, D. [Institut fuer Solarenergieforschung GmbH Hameln/Emmerthal (ISFH), Emmerthal (Germany). Gruppe Photovoltaik-Systeme; Stellbogen, D. [Zentrum fuer Sonnenenergie- und Wasserstoff-Forschung Baden-Wuerttemberg (ZSW), Stuttgart (Germany). Fachgebiet Photovoltaische Anlagentechnik

    1998-02-01

    PV facades can provide several additional functions such as weather protection, thermal insulation, daylighting or sun protection. On the other hand, specific operating conditions for PV facades must be taken into account when selecting components and designing the system. Depending on ventilation conditions, there is a large range of maximum module temperatures. South-oriented PV facades receive about 30% less yearly irradiation than an optimally inclined PV generator, hence reflection losses are approximately 4% higher. The maximum of yearly irradiation lies only in the 400-600 W/m{sup 2} range. Surrounding buildings and/or vegetation can impair performance of the PV-facades. For a south-oriented PV facade an annual yield in the range of 470-560 kwh/kW{sub p}.a has been prodicted which was verified by operating results of eight PV facades. (orig.) [Deutsch] Photovoltaik (PV) Fassaden ermoeglichen neben der Stromerzeugung zusaetzliche Funktionen wie Wetterschutz bzw. Waermedaemmung des Gebaeudes oder Tageslichtnutzung bzw. Sonnenschutz der Innenraeume. Allerdings muessen fassadenspezifische Betriebsbedingungen, bei der Komponentenauswahl und Systemauslegung beruecksichtigt werden. Unterschiedliche Hinterlueftungsbedingungen fuehren zu einer grossen Bandbreite der maximalen Modultemperatur. PV-Suedfassaden empfangen etwa 30% weniger Jahreseinstrahlung als ein optimal geneigter PV-Generator. Die Haelfte der jaehrlichen Einstrahlung trifft mit Einfallswinkeln groesser 50 auf die vertikal angeordneten Module wodurch die Reflexionsverluste um ca. 4% hoeher sind. Das Maximum der Jahreseinstrahlung liegt nur um 400-600 W/m{sup 2} und erreicht selten Werte ueber 800 W/m{sup 2}. Umliegende Gebaeude oder Vegetation koennen zu Teilabschattungen des Generators fuehren. Fuer eine vertikale PV-Suedfassade wird ein Jahresenergieertrag in Hoehe von 470-560 kWh/kW{sub p}.a prognostiziert, der anhand der Betriebsergebnisse von acht PV-Fassadenanlagen verifiziert werden konnte

  16. Rheological Behavior of Tomato Fiber Suspensions Produced by High Shear and High Pressure Homogenization and Their Application in Tomato Products

    Science.gov (United States)

    Sun, Ping; Adhikari, Benu P.; Li, Dong

    2018-01-01

    This study investigated the effects of high shear and high pressure homogenization on the rheological properties (steady shear viscosity, storage and loss modulus, and deformation) and homogeneity in tomato fiber suspensions. The tomato fiber suspensions at different concentrations (0.1%–1%, w/w) were subjected to high shear and high pressure homogenization and the morphology (distribution of fiber particles), rheological properties, and color parameters of the homogenized suspensions were measured. The homogenized suspensions were significantly more uniform compared to unhomogenized suspension. The homogenized suspensions were found to better resist the deformation caused by external stress (creep behavior). The apparent viscosity and storage and loss modulus of homogenized tomato fiber suspension are comparable with those of commercial tomato ketchup even at the fiber concentration as low as 0.5% (w/w), implying the possibility of using tomato fiber as thickener. The model tomato sauce produced using tomato fiber showed desirable consistency and color. These results indicate that the application of tomato fiber in tomato-based food products would be desirable and beneficial. PMID:29743890

  17. Early Arabidopsis root hair growth stimulation by pathogenic strains of Pseudomonas syringae.

    Science.gov (United States)

    Pecenková, Tamara; Janda, Martin; Ortmannová, Jitka; Hajná, Vladimíra; Stehlíková, Zuzana; Žárský, Viktor

    2017-09-01

    Selected beneficial Pseudomonas spp. strains have the ability to influence root architecture in Arabidopsis thaliana by inhibiting primary root elongation and promoting lateral root and root hair formation. A crucial role for auxin in this long-term (1week), long-distance plant-microbe interaction has been demonstrated. Arabidopsis seedlings were cultivated in vitro on vertical plates and inoculated with pathogenic strains Pseudomonas syringae pv. maculicola (Psm) and P. syringae pv. tomato DC3000 (Pst), as well as Agrobacterium tumefaciens (Atu) and Escherichia coli (Eco). Root hair lengths were measured after 24 and 48h of direct exposure to each bacterial strain. Several Arabidopsis mutants with impaired responses to pathogens, impaired ethylene perception and defects in the exocyst vesicle tethering complex that is involved in secretion were also analysed. Arabidopsis seedling roots infected with Psm or Pst responded similarly to when infected with plant growth-promoting rhizobacteria; root hair growth was stimulated and primary root growth was inhibited. Other plant- and soil-adapted bacteria induced similar root hair responses. The most compromised root hair growth stimulation response was found for the knockout mutants exo70A1 and ein2. The single immune pathways dependent on salicylic acid, jasmonic acid and PAD4 are not directly involved in root hair growth stimulation; however, in the mutual cross-talk with ethylene, they indirectly modify the extent of the stimulation of root hair growth. The Flg22 peptide does not initiate root hair stimulation as intact bacteria do, but pretreatment with Flg22 prior to Psm inoculation abolished root hair growth stimulation in an FLS2 receptor kinase-dependent manner. These early response phenomena are not associated with changes in auxin levels, as monitored with the pDR5::GUS auxin reporter. Early stimulation of root hair growth is an effect of an unidentified component of living plant pathogenic bacteria. The root

  18. Functional genomics of tomato

    Indian Academy of Sciences (India)

    2014-10-20

    Oct 20, 2014 ... 1Repository of Tomato Genomics Resources, Department of Plant Sciences, School .... Due to its position at the crossroads of Sanger's sequencing .... replacement for the microarray-based expression profiling. .... during RNA fragmentation step prior to library construction, ...... tomato pollen as a test case.

  19. The case for better PV forecasting

    DEFF Research Database (Denmark)

    Alet, Pierre-Jean; Efthymiou, Venizelos; Graditi, Giorgio

    2016-01-01

    Rising levels of PV penetration mean increasingly sophisticated forecasting technologies are needed to maintain grid stability and maximise the economic value of PV systems. The Grid Integration working group of the European Technology and Innovation Platform – Photovoltaics (ETIP PV) shares the ...

  20. Development of a GIS Tool for High Precision PV Degradation Monitoring and Supervision: Feasibility Analysis in Large and Small PV Plants

    Directory of Open Access Journals (Sweden)

    Miguel de Simón-Martín

    2017-06-01

    Full Text Available It is well known that working photovoltaic (PV plants show several maintenance needs due to wiring and module degradation, mismatches, dust, and PV cell defects and faults. There are a wide range of theoretical studies as well as some laboratory tests that show how these circumstances may affect the PV production. Thus, it is mandatory to evaluate the whole PV plant performance and, then, its payback time, profitability, and environmental impact or carbon footprint. However, very few studies include a systematic procedure to quantify and supervise the real degradation effects and fault impacts on the field. In this paper, the authors first conducted a brief review of the most frequent PV faults and the degradation that can be found under real conditions of operation of PV plants. Then, they proposed and developed an innovative Geographic Information System (GIS application to locate and supervise them. The designed tool was applied to both a large PV plant of 108 kWp and a small PV plant of 9 kWp installed on a home rooftop. For the large PV plant, 24 strings of PV modules were modelized and introduced into the GIS application and every module in the power plant was studied including voltage, current, power, series and parallel resistances, fill factor, normalized PV curve to standard test conditions (STC, thermography and visual analysis. For the small PV installation three strings of PV panels were studied identically. It must be noted that PV modules in this case included power optimizers. The precision of the study enabled the researchers to locate and supervise up to a third part of every PV cell in the system, which can be adequately georeferenced. The developed tool allows both the researchers and the investors to increase control of the PV plant performance, to lead to better planning of maintenance actuations, and to evaluate several PV module replacement strategies in a preventive maintenance program. The PV faults found include hot

  1. Adiabatic Rearrangement of Hollow PV Towers

    Directory of Open Access Journals (Sweden)

    Eric A Hendricks

    2010-10-01

    Full Text Available Diabatic heating from deep moist convection in the hurricane eyewall produces a towering annular structure of elevated potential vorticity (PV. This structure has been referred to as a hollow PV tower. The sign reversal of the radial gradient of PV satisfies the Charney-Stern necessary condition for combined barotropic-baroclinic instability. For thin enough annular structures, small perturbations grow exponentially, extract energy from the mean flow, and lead to hollow tower breakdown, with significant vortex structural and intensity change. The three-dimensional adiabatic rearrangements of two prototypical hurricane-like hollow PV towers (one thick and one thin are examined in an idealized framework. For both hollow towers, dynamic instability causes air parcels with high PV to be mixed into the eye preferentially at lower levels, where unstable PV wave growth rates are the largest. Little or no mixing is found to occur at upper levels. The mixing at lower and middle levels is most rapid for the breakdown of the thin hollow tower, consistent with previous barotropic results. For both hollow towers, this advective rearrangement of PV affects the tropical cyclone structure and intensity in a number of ways. First, the minimum central pressure and maximum azimuthal mean velocity simultaneously decrease, consistent with previous barotropic results. Secondly, isosurfaces of absolute angular momentum preferentially shift inward at low levels, implying an adiabatic mechanism by which hurricane eyewall tilt can form. Thirdly, a PV bridge, similar to that previously found in full-physics hurricane simulations, develops as a result of mixing at the isentropic levels where unstable PV waves grow most rapidly. Finally, the balanced mass field resulting from the PV rearrangement is warmer in the eye between 900 and 700 hPa. The location of this warming is consistent with observed warm anomalies in the eye, indicating that in certain instances the hurricane

  2. Engineering drought tolerant tomato plants over-expressing BcZAT12 gene encoding a C₂H₂ zinc finger transcription factor.

    Science.gov (United States)

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

    2013-01-01

    Efficient genetic transformation of cotyledonary explants of tomato (Solanum lycopersicum, cv. H-86, Kashi vishesh) was obtained. Disarmed Agrobacterium tumifaciens strain GV 3101 was used in conjugation with binary vector pBinAR containing a construct consisting of the coding sequence of the BcZAT12 gene under the regulatory control of the stress inducible Bclea1a promoter. ZAT12 encodes a C₂H₂ zinc finger protein which confers multiple abiotic stress tolerance to plants. Integration of ZAT12 gene into nuclear genome of individual kanamycin resistant transformed T₀ tomato lines was confirmed by Southern blot hybridization with segregation analysis of T(1) plants showing Mendelian inheritance of the transgene. Expression of ZAT12 in drought-stressed transformed tomato lines was verified in T₂ generation plants using RT-PCR. Of the six transformed tomato lines (ZT1-ZT6) the transformants ZT1 and ZT5 showed maximum expression of BcZAT12 gene transcripts when exposed to 7 days drought stress. Analysis of relative water content (RWC), electrolyte leakage (EL), chlorophyll colour index (CCI), H₂O₂ level and catalase activity suggested that tomato BcZAT12 transformants ZT1 and ZT5 have significantly increased levels of drought tolerance. These results suggest that BcZAT12 transformed tomato cv. H-86 has real potential for molecular breeding programs aimed at augmenting yield of tomato in regions affected with drought stress. Copyright © 2012 Elsevier Ltd. All rights reserved.

  3. Molecular Mechanisms of Attenuation of the Sabin Strain of Poliovirus Type 3

    OpenAIRE

    Guest, Stephen; Pilipenko, Evgeny; Sharma, Kamal; Chumakov, Konstantin; Roos, Raymond P.

    2004-01-01

    Mutations critical for the central nervous system (CNS) attenuation of the Sabin vaccine strains of poliovirus (PV) are located within the viral internal ribosome entry site (IRES). We examined the interaction of the IRESs of PV type 3 (PV3) and Sabin type 3 (Sabin3) with polypyrimidine tract-binding protein (PTB) and a neural cell-specific homologue, nPTB. PTB and nPTB were found to bind to a site directly adjacent to the attenuating mutation, and binding at this site was less efficient on t...

  4. Parallel experimental study of a novel super-thin thermal absorber based photovoltaic/thermal (PV/T system against conventional photovoltaic (PV system

    Directory of Open Access Journals (Sweden)

    Peng Xu

    2015-11-01

    Full Text Available Photovoltaic (PV semiconductor degrades in performance due to temperature rise. A super thin-conductive thermal absorber is therefore developed to regulate the PV working temperature by retrofitting the existing PV panel into the photovoltaic/thermal (PV/T panel. This article presented the parallel comparative investigation of the two different systems through both laboratory and field experiments. The laboratory evaluation consisted of one PV panel and one PV/T panel respectively while the overall field system involved 15 stand-alone PV panels and 15 retrofitted PV/T panels. The laboratory testing results demonstrated the PV/T panel could achieve the electrical efficiency of about 16.8% (relatively 5% improvement comparing with the stand-alone PV panel, and yield an extra amount of heat with thermal efficiency of nearly 65%. The field testing results indicated that the hybrid PV/T panel could enhance the electrical return of PV panels by nearly 3.5%, and increase the overall energy output by nearly 324.3%. Further opportunities and challenges were then discussed from aspects of different PV/T stakeholders to accelerate the development. It is expected that such technology could become a significant solution to yield more electricity, offset heating load freely and reduce carbon footprint in contemporary energy environment.

  5. Economic Sustainability of Italian Greenhouse Cherry Tomato

    Directory of Open Access Journals (Sweden)

    Riccardo Testa

    2014-11-01

    Full Text Available Greenhouse tomato cultivation plays an important role in Sicily, being the primary production area in Italy, due to its favorable pedo-climatic conditions that permit extra-seasonal productions. In Sicily, more than half of greenhouse tomato production is derived from the Province of Ragusa on the southeastern coast, where especially cherry tomato typologies are cultivated. Over the last decade, the Ragusa Province has registered a decrease both in terms of greenhouse tomato area and harvested production due to several structural problems that would require restructuring of the tomato supply chain. Thus, since recognition of real costs and profitability of tomato growing is a vital issue, both from the perspective of the farm, as well as from that of the entrepreneur, the aim of this paper was to analyze the economic sustainability of Sicilian greenhouse cherry tomato cultivated in the Ragusa Province. In particular, an economic analysis on 30 representative farms was conducted in order to estimate production costs and profits of greenhouse cherry tomato. According to our results, the lack of commercial organization, which characterizes the small farms we surveyed, determines low contractual power for farmers and, consequently, low profitability.

  6. The market for photovoltaic (PV) technology

    International Nuclear Information System (INIS)

    Frantzis, L.; Vejtasa, K.M.

    1993-01-01

    This paper describes a study that was intended to provide the Electric Power Research Institute (EPRI) with a market analysis for photovoltaic (PV) technologies under development by EPRI and others. The analysis was to focus on markets and factors leading to significant incremental growth for PV demand, large enough to support more efficient scale PV manufacturing capacity. EPRI anticipates that PV ultimately could provide grid-connected power, however, the 1995--2010 market dynamics are uncertain. The specific objectives of this study, therefore, were to: determine what major future domestic US markets for PV technologies will emerge and provide enough volume to support significant improvements in manufacturing costs through manufacturing economies of scale; provide insight on what is needed to gain acceptance of PV technologies for electric power generation in those major markets; provide insight on when investments in demonstration and manufacturing facilities should be made and what is needed to be successful in each element of the business that these markets could support (e.g., technology development, manufacturing, sales, installation, and service); and provide key insights on the requirements for commercial success of PV in the utility sector

  7. Mineral Content in Leaves of Tomato Plants Grafted on Solanum Rootstocks

    OpenAIRE

    松添, 直隆; 間, 浩美; 花田, 勝美; モハメド, アリ; 大久保, 敬; 藤枝, 國光

    1995-01-01

    Nutrient uptake of tomato plants cv. Momotaro grafted on Solanum sisymbriifoliulm, S. torvum and S. toxicarium which are resistant to soil-born disease were compared with tomato grafted on its own root, a tomato/tomato, scion/rootstock combination. Mineral content in leaves of tomato/S. sisymbriifoliulm was nearly equal to that of tomato/tomato. In leaves of tomato/S. torvum, nitrogen content was higher, and magnesium content was lower than those of tomato/tomato. Furthermore, phosphorus and ...

  8. Plastid and Stromule Morphogenesis in Tomato

    Science.gov (United States)

    PYKE, KEVIN A.; HOWELLS, CAROLINE A.

    2002-01-01

    By using green fluorescent protein targeted to the plastid organelle in tomato (Lycopersicon esculentum Mill.), the morphology of plastids and their associated stromules in epidermal cells and trichomes from stems and petioles and in the chromoplasts of pericarp cells in the tomato fruit has been revealed. A novel characteristic of tomato stromules is the presence of extensive bead‐like structures along the stromules that are often observed as free vesicles, distinct from and apparently unconnected to the plastid body. Interconnections between the red pigmented chromoplast bodies are common in fruit pericarp cells suggesting that chromoplasts could form a complex network in this cell type. The potential implications for carotenoid biosynthesis in tomato fruit and for vesicles originating from beaded stromules as a secretory mechanism for plastids in glandular trichomes of tomato is discussed. PMID:12466096

  9. Tomato immune receptor Ve1 recognizes effector of multiple fungal pathogens uncovered by genome and RNA sequencing

    NARCIS (Netherlands)

    Jonge, de R.; Esse, van H.P.; Maruthachalam, K.; Bolton, M.D.; Santhanam, P.; Keykha Saber, M.; Zhang, Z.; Usami, T.; Lievens, B.; Subbarao, K.V.; Thomma, B.

    2012-01-01

    Fungal plant pathogens secrete effector molecules to establish disease on their hosts, and plants in turn use immune receptors to try to intercept these effectors. The tomato immune receptor Ve1 governs resistance to race 1 strains of the soil-borne vascular wilt fungi Verticillium dahliae and

  10. Development of immunofluorescence colony staining (IFC) for detection of Xanthomonas campestris pv. vesicatoria and Clavibacter michiganensis subsp michiganensis in tomato seeds

    NARCIS (Netherlands)

    Nemeth, J.; Vuurde, van J.W.L.

    2006-01-01

    Immunofluorescence colony-staining (IFC) is based on sample pour plating in combination with immunofluorescence staining for recognition of the target colony. IFC was optimised for detecting Xanthomonas campestris pv. vesicatoria (Xcv) and Clavibacter michiganensis subsp. michiganensis (Cmm) in

  11. AP2/ERF Transcription Factors Involved in Response to Tomato Yellow Leaf Curly Virus in Tomato

    Directory of Open Access Journals (Sweden)

    Ying Huang

    2016-07-01

    Full Text Available Tomato yellow leaf curly virus (TYLCV, transmitted by the whitefly (, causes leaf curling and yellowing, plant dwarfism, and growth inhibition in tomato ( L.. The APETALA2 (AP2 and ethylene response factor (ERF transcription factor (TF family, the largest plant-specific TF family, was identified to function in plant development and pathogen defense. Our study aimed to analyze the mechanism underlying the function of ERF (SlERF TFs in response to TYLCV infection and improve useful information to increase the resistance to TYLCV in tomato. A total of 22 tomato AP2/ERF TFs in response to TYLCV were identified according to transcriptome database. Five ERF-B3 TFs were identified in cultivars Hongbeibei (highly resistant, Zheza-301, Zhefen-702 (both resistant, Jinpeng-1, and Xianke-6 (both susceptible. Interaction network indicated that SlERF TFs could interact with mitogen-activated protein kinase (MAPK. Expression profiles of five ERF-B3 genes (, , , , and were detected by quantitative real-time–polymerase chain reaction (qRT-PCR after TYLCV infection in five tomato cultivars. expression was upregulated in five tomato cultivars. The expressions of three genes (, , and were upregulated in Zheza-301 and Zhefen-702. and expressions were downregulated in Hongbeibei and Xianke-6, respectively. Yeast one-hybrid showed that the GCC-box binding ability of ERF-B3 TFs differed in resistant and susceptible tomato cultivars. Expression profiles were related to the GCC-box binding ability of SlERF TFs in resistant and susceptible tomato cultivars. The defense mechanism underlying the tomato’s response to TYLCV involved a complicated network, which provided important information for us in breeding and genetic analysis.

  12. Pepino mosaic virus and Tomato chlorosis virus causing mixed infection in protected tomato crops in Sicily

    Directory of Open Access Journals (Sweden)

    SALVATORE DAVINO

    2008-07-01

    Full Text Available An unusual virus-like yellow leaf disorder associated with fruit marbling was observed during the winter of 2005 in some greenhouse tomato crops in the province of Ragusa Sicily (Southern Italy. Leaf samples from 250 symptomatic tomato plants were serologically tested by DAS-ELISA technique for 5 viruses: Tomato spotted wilt virus (TSWV, Impatiens necrotic spot virus (INSV, Tobacco mosaic virus (TMV, Cucumber mosaic virus (CMV and Pepino mosaic virus (PepMV. PepMV was detected in 215 of the samples. The virus was mechanically transmitted to cucumber, wild metel, wild tobacco and ‘Rio Grande’ tomato. The experimental host range of PepMV-Ragusa differed from that of the PepMV found in Sardinia in 2001, which infected ‘Camone’ tomato. By applying RT-PCR to 25 PepMV-infected tomato plants, the expected 844 bp DNA fragment for PepMV and the expected 439 bp DNA fragment for Tomato chlororis virus (ToCV were obtained from all the samples tested. Sequences of the obtained amplicons were used to study the phylogenetic relationships of the viruses with isolates from other countries. Nucleotide sequence alignments showed that the sequence CP-PepMV-Ragusa (Genbank acc. No. DQ 517884 were 99% homologous with both US2 and Spain-Murcia isolates, while those of ToCV-Ragusa (Genbank acc. No. DQ517885 isolate HSP70, were 99% homologous with the Florida isolate, and 98% with the Lebanon isolate. The results proved that the unusual disorder found in greenhouse tomatoes in Sicily can be associated with infections by PepMV and ToCV, reported for the first time in a mixed infection.

  13. Carotenoids and lycopene content in fresh and dried tomato fruits and tomato juice

    Directory of Open Access Journals (Sweden)

    Andrea Mendelová

    2013-01-01

    Full Text Available Important component of the tomato are carotenoid dyes, especially lycopene. The importance of lycopene in the diet of people in recent years has grown mainly for its pharmacological effects due to its ability to reduce the risk of carcinoma diseases and prevention of cardiovascular diseases. The aim of this work was to analyze the content of total carotenoids and lycopene in 8 varieties of tomato and to monitor dynamic changes after their different treatments (heating, drying. The experiment included following tomato varieties: Bambino F1, Darina F1, Diana F1, Denár, Milica F1, Orange F1, Paulína F1, Šejk F1.We found that processing of tomato fruits into juices and dried slices positively affected the presence of carotenoids and lycopene. Processing leads to an increase in the content of carotenoids that can be attributed to better availability of these components in the human body.

  14. Design of Tomato Drying System by Utilizing Brine Geothermal

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

  16. Accumulation of anthocyanins in tomato skin extends shelf life.

    Science.gov (United States)

    Bassolino, Laura; Zhang, Yang; Schoonbeek, Henk-Jan; Kiferle, Claudia; Perata, Pierdomenico; Martin, Cathie

    2013-11-01

    Shelf life is one of the most important traits for the tomato (Solanum lycopersicum) industry. Two key factors, post-harvest over-ripening and susceptibility to post-harvest pathogen infection, determine tomato shelf life. Anthocyanins accumulate in the skin of Aft/Aft atv/atv tomatoes, the result of introgressing alleles affecting anthocyanin biosynthesis in fruit from two wild relatives of tomato, which results in extended fruit shelf life. Compared with ordinary, anthocyanin-less tomatoes, the fruits of Aft/Aft atv/atv keep longer during storage and are less susceptible to Botrytis cinerea, a major tomato pathogen, post-harvest. Using genetically modified tomatoes over-producing anthocyanins, we confirmed that skin-specific accumulation of anthocyanins in tomato is sufficient to reduce the susceptibility of fruit to Botrytis cinerea. Our data indicate that accumulation of anthocyanins in tomato fruit, achieved either by traditional breeding or genetic engineering can be an effective way to extend tomato shelf life. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust.

  17. ECONOMIC EFFICIENCY IN TOMATOES PRODUCTION IN GREENHOUSES

    Directory of Open Access Journals (Sweden)

    A POPESCU

    2003-07-01

    Full Text Available This study aimed to appreciate the evolution of economic efficiency in tomatoes production in greenhouses within a private firm situated next to the capital. The firm owns 4 ha greenhouses and the weight of tomatoes crop in the cultivated area is just 38.75 %. In fact, during the last three years, the tomatoes cultivated surface has been diminished in favour of flowers production which, like tomatoes production is an important income source for any producer. The reduction of the tomatoes cultivated area was compensated by the increase of intensification grade using new high performance hybrids and modern technologies. Thus, the scientific production management has been looking for maintaining the total production at the same level from a year to another by an increased average tomatoes yield by 53.33 % . The continuous increase of farm input price has doubled the cost per surface unit and increased the cost per tomatoes kilogram by 33 %. The increase of tomatoes demand and of market price by 31 % have had a positive influence on the farm incomes which has doubled during the last three years. In the year 2000, the company has obtained USD 41,818 income/ha of which subtracting the related production cost we can easily get USD 4,815 profit/ha. The average profit rate recorded by the firm is 13 % in the period 2000-2002, when the study was made. As a conclusion, tomatoes production in greenhouses is a good deal. To keep a high economic efficiency, under the diminishing of the cultivated area, the producers have to increase average tomatoes production by using high performance technology based on high economic value hybrids.

  18. Isolation and composition of chromoplasts from tomatoes.

    Science.gov (United States)

    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.

  19. PRESERVATIVE POTENTIAL OF PURIFIED BACTERIOCIN PRODUCED FROM BREVIBACILLUS BORSTELENSIS AG1 ISOLATED FROM MARCHA – A TRADITIONAL WINE STARTER CULTURE CAKE IN TOMATO PASTE

    OpenAIRE

    Anupama Gupta; Nivedita Sharma; Neha Gautam

    2015-01-01

    Purified bacteriocin produced from Brevibacillus borstelensis AG1 isolated from Marcha a local wine starter herbal cake, was used to enhance the shelf life of tomato paste. Preservative effect of purified bacteriocin was studied for nine days in tomato paste inoculated with food borne pathogens and was compared to commercial biopreservative – nisin and chemical preservative – sodium benzoate. The indicator strains i.e. Listeria monocytogenes MTCC839, Bacillus subtilis CRI and Clostridium perf...

  20. Studies on the reaction in tissue culture of tomato genotypes under biotic stress

    Directory of Open Access Journals (Sweden)

    Ewa Hanus-Fajerska

    2014-01-01

    Full Text Available Plant regeneration in vitro from virus-infected somatic tomato (Lycopersicon sp. tissue was performed. Regeneration experiments were started after the determination of virus presence, using enzyme-linked immunosorbent assay, in leaves used as a source of explants. Leaf explants infected with selected strains of tomato mosaic Tobamovirus or cucumber mosaic Cucumovirus respectively, were cultured on a standarised MS agar medium to induce adventitious shoots, which were afterwards excised, rooted in vitro and cultured to plants. Explants were also screened for their ability to produce callus. Diverse effects of viral infection, ranging from stimulation to inhibition of callus formation and of morphogenesis rate, were observed. The health condition of the tissue proved to affect regeneration potential of Lycopersicon esculentum, whereas wild accesions did not react in that case so distinctly. In cultivated tomato was encountered the decline in competence to reproduce shoots adventitiously in infected tissue. There was also relationship between donor plant health condition and adventitious root formation in regenerated shoots. Experiments with short-term cultures of L. esculenum reveled also that a certain number of shoots regenerated from diseased tissue can be virus-free.

  1. Identification of rat Rosa26 locus enables generation of knock-in rat lines ubiquitously expressing tdTomato.

    Science.gov (United States)

    Kobayashi, Toshihiro; Kato-Itoh, Megumi; Yamaguchi, Tomoyuki; Tamura, Chihiro; Sanbo, Makoto; Hirabayashi, Masumi; Nakauchi, Hiromitsu

    2012-11-01

    Recent discovery of a method for derivation and culture of germline-competent rat pluripotent stem cells (PSCs) enables generation of transgenic rats or knock-out rats via genetic modification of such PSCs. This opens the way to use rats, as is routine in mice, for analyses of gene functions or physiological features. In mouse or human, one widely used technique to express a gene of interest stably and ubiquitously is to insert that gene into the Rosa26 locus via gene targeting of PSCs. Rosa26 knock-in mice conditionally expressing a reporter or a toxin gene have contributed to tracing or ablation of specific cell lineages. We successfully identified a rat orthologue of the mouse Rosa26 locus. Insertion of tdTomato, a variant of red fluorescent protein, into the Rosa26 locus of PSCs of various rat strains allows ubiquitous expression of tdTomato. Through germline transmission of one Rosa26-tdTomato knock-in embryonic stem cell line, we also obtained tdTomato knock-in rats. These expressed tdTomato ubiquitously throughout their bodies, which indicates that the rat Rosa26 locus conserves functions of its orthologues in mouse and human. The new tools described here (targeting vectors, knock-in PSCs, and rats) should be useful for a variety of research using rats.

  2. Experimental investigation of PV modules recycling; PV module recycle no jikkenteki kento

    Energy Technology Data Exchange (ETDEWEB)

    Unagida, H; Kurokawa, K [Tokyo University of Agriculture and Technology, Tokyo (Japan); Sakuta, K; Otani, K; Murata, K [Electrotechnical Laboratory, Tsukuba (Japan)

    1997-11-25

    Recycling, cost/energy analysis and recovery experiment were made on crystalline silicon PV modules with EVA(ethylene vinyl acetate)-laminated structure. The life of modules is dependent not on performance deterioration of PV cells themselves but on yellowing or poor transmittance of EVA caused by ultraviolet ray, and disconnection between cells by thermal stress. Recovery is carried out in 3 stages of cell, wafer and material. Recovery in the stages of cell and wafer results in considerable reduction of energy and cost. The recovery experiment was carried out using PV module samples prepared by cutting the modules into 25times15mm pieces after removing Al frames from the used modules, peeling back sheets and cutting off EVA. Since a nitric acid process at 70-80degC can dissolve EVA effectively, it is promising for reuse of surface glass and PV cells as they are. This process is also carried out under a condition around room temperature and pressure, contributing to cost reduction and energy saving for recycling. Generation of harmful NOx is only a problem to be solved. 2 refs., 6 figs., 1 tab.

  3. A Practical Irradiance Model for Bifacial PV Modules

    Energy Technology Data Exchange (ETDEWEB)

    Marion, Bill; MacAlpine, Sara; Deline, Chris; Asgharzadeh, Amir; Toor, Fatima; Riley, Daniel; Stein, Joshua; Hansen, Clifford

    2017-06-21

    A model, suitable for a row or multiple rows of photovoltaic (PV) modules, is presented for estimating the backside irradiance for bifacial PV modules. The model, which includes the effects of shading by the PV rows, is based on the use of configuration factors to determine the fraction of a source of irradiance that is received by the backside of the PV module. Backside irradiances are modeled along the sloped height of the PV module, but assumed not to vary along the length of the PV row. The backside irradiances are corrected for angle-of-incidence losses and may be added to the front side irradiance to determine the total irradiance resource for the PV cell. Model results are compared with the measured backside irradiances for NREL and Sandia PV systems, and with results when using ray tracing software.

  4. POSTHARVEST FUNGAL DETERIORATION OF TOMATO ...

    African Journals Online (AJOL)

    Dr A.B.Ahmed

    commercial food vendors often intentionally use physically damaged tomatoes and ... The production of the bulk of the fresh tomato and. 'tatase' in Nigeria is in ...... mycotoxin contamination of food include but not limited to mycotoxicoses, liver ...

  5. Resistance of functional Lactobacillus plantarum strains against food stress conditions.

    Science.gov (United States)

    Ferrando, Verónica; Quiberoni, Andrea; Reinhemer, Jorge; Suárez, Viviana

    2015-06-01

    The survival of three Lactobacillus plantarum strains (Lp 790, Lp 813 and Lp 998) with functional properties was studied taking into account their resistance to thermal, osmotic and oxidative stress factors. Stress treatments applied were: 52 °C-15 min (Phosphate Buffer pH 7, thermal shock), H2O2 0.1% (p/v) - 30 min (oxidative shock) and NaCl aqueous solution at 17, 25 and 30% (p/v) (room temperature - 1 h, osmotic shock). The osmotic stress was also evaluated on cell growth in MRS broth added of 2, 4, 6, 8 and 10% (p/v) of NaCl, during 20 h at 30 °C. The cell thermal adaptation was performed in MRS broth, selecting 45 °C for 30 min as final conditions for all strains. Two strains (Lp 813 and Lp 998) showed, in general, similar behaviour against the three stress factors, being clearly more resistant than Lp 790. An evident difference in growth kinetics in presence of NaCl was observed between Lp 998 and Lp 813, Lp998 showing a higher optical density (OD570nm) than Lp 813 at the end of the assay. Selected thermal adaptation improved by 2 log orders the thermal resistance of both strains, but cell growth in presence of NaCl was enhanced only in Lp 813. Oxidative resistance was not affected with this thermal pre-treatment. These results demonstrate the relevance of cell technological resistance when selecting presumptive "probiotic" cultures, since different stress factors might considerably affect viability or/and performance of the strains. The incidence of stress conditions on functional properties of the strains used in this work are currently under research in our group. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Analysis of Clonostachys rosea-induced resistance to tomato gray mold disease in tomato leaves.

    Directory of Open Access Journals (Sweden)

    Liana Dalcantara Ongouya Mouekouba

    Full Text Available Tomato gray mold disease, caused by Botrytis cinerea, is a serious disease in tomato. Clonostachys rosea is an antagonistic microorganism to B. cinerea. To investigate the induced resistance mechanism of C. rosea, we examined the effects of these microorganisms on tomato leaves, along with changes in the activities of three defense enzymes (PAL, PPO, GST, second messengers (NO, H2O2, O2(- and phytohormones (IAA, ABA, GA3, ZT, MeJA, SA and C2H4. Compared to the control, all treatments induced higher levels of PAL, PPO and GST activity in tomato leaves and increased NO, SA and GA3 levels. The expression of WRKY and MAPK, two important transcription factors in plant disease resistance, was upregulated in C. rosea- and C. rosea plus B. cinerea-treated samples. Two-dimensional gel electrophoresis analysis showed that two abundant proteins were present in the C. rosea plus B. cinerea-treated samples but not in the other samples. These proteins were determined (by mass spectrum analysis to be LEXYL2 (β-xylosidase and ATP synthase CF1 alpha subunit. Therefore, C. rosea plus B. cinerea treatment induces gray mold resistance in tomato. This study provides a basis for elucidating the mechanism of C. rosea as a biocontrol agent.

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

    Science.gov (United States)

    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.

  8. Impact of high-intensity pulsed electric fields on carotenoids profile of tomato juice made of moderate-intensity pulsed electric field-treated tomatoes.

    Science.gov (United States)

    Vallverdú-Queralt, Anna; Odriozola-Serrano, Isabel; Oms-Oliu, Gemma; Lamuela-Raventós, Rosa M; Elez-Martínez, Pedro; Martín-Belloso, Olga

    2013-12-01

    The effect of pulsed electric fields (PEF) on the carotenoid content of tomato juices was studied. First, moderate-intensity PEF (MIPEF) was applied to raw tomatoes. Afterwards, MIPEF-treated and untreated tomatoes were immediately refrigerated at 4 °C for 24 h and then, they were separately ground to produce tomato juices. Juices were treated by heat treatments or by high-intensity PEF (HIPEF) and stored under refrigeration for 56 days. MIPEF treatment of tomatoes increased the content of carotenoid compounds in tomato juices. An enhancement of 63-65% in 15-cis-lycopene was observed in juices prepared with MIPEF-treated tomatoes. A slight increase in cis-lycopene isomers was observed over time, whereas other carotenoids slightly decreased. However, HIPEF treated tomato juices maintained higher carotenoid content (10-20%) through the storage time than thermally and untreated juices. The combination of MIPEF and HIPEF treatments could be used not only to produce tomato juices with high carotenoid content but also, to maintain higher the carotenoid content during storage time. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. Power of design - the future of building-integrated PV

    International Nuclear Information System (INIS)

    Abbate, Cinzia

    2001-01-01

    This paper discusses strategies to make building integrated photovoltaic (PV) systems more acceptable and to allow PV material to compete with conventional construction material. The history of developments in building integration and difficulties encountered by architects wishing to use PV products are explored, and the Dutch Amersfoot project in Utrecht involving a new suburb of 501 house covered with PV panels is described. Questions raised regarding architectural integration of PV systems, and PV systems and the construction market are discussed. The Italian PV programme, financial and political constraints, and the positioning of PV on existing structures are reported

  10. PSCAD Modules Representing PV Generator

    Energy Technology Data Exchange (ETDEWEB)

    Muljadi, E.; Singh, M.; Gevorgian, V.

    2013-08-01

    Photovoltaic power plants (PVPs) have been growing in size, and the installation time is very short. With the cost of photovoltaic (PV) panels dropping in recent years, it can be predicted that in the next 10 years the contribution of PVPs to the total number of renewable energy power plants will grow significantly. In this project, the National Renewable Energy Laboratory (NREL) developed a dynamic modeling of the modules to be used as building blocks to develop simulation models of single PV arrays, expanded to include Maximum Power Point Tracker (MPPT), expanded to include PV inverter, or expanded to cover an entire PVP. The focus of the investigation and complexity of the simulation determines the components that must be included in the simulation. The development of the PV inverter was covered in detail, including the control diagrams. Both the current-regulated voltage source inverter and the current-regulated current source inverter were developed in PSCAD. Various operations of the PV inverters were simulated under normal and abnormal conditions. Symmetrical and unsymmetrical faults were simulated, presented, and discussed. Both the three-phase analysis and the symmetrical component analysis were included to clarify the understanding of unsymmetrical faults. The dynamic model validation was based on the testing data provided by SCE. Testing was conducted at SCE with the focus on the grid interface behavior of the PV inverter under different faults and disturbances. The dynamic model validation covers both the symmetrical and unsymmetrical faults.

  11. OnToPV - a virtual guidance through the PV-plant ''Solardach New Munich Trade Fair''; OnToPV - eine virtuelle Fuehrung druch die PV-Anlage ''Solardach Neue Messe Muenchen''

    Energy Technology Data Exchange (ETDEWEB)

    Stich, C.; Becker, G.; Zehner, M. [Fachhochschule Muenchen (Germany). Fachbereich Elektrotechnik; Giesler, B. [Shell Solar GmbH, Muenchen (Germany); Weber, W.; Flade, F. [Solarenergiefoerderverein Bayern e.V., Muenchen (Germany)

    2003-07-01

    OnToPV is the project of an online tour guide through the PV-plant of the new Munich trade fair. The first focs was to provide an interactive circuit of a PV-plant. Within a virtual tour different areas of the plant should be made accessible over the internet. For this purpose a three-dimensional, multimedia guidance was developed for the PV-plant of the new Munich trade fair with informative diagrams, *.pdf-files and retrievable video-files. In such a way interested internet-users could experience with minimum system requirements, local- and time-independently the PV-plant in its structure and components and could receive different background informations in addition. From the view of the plant operators such an internet project serves on the one hand as an additional source of information where questions could be referred to and on the other hand as sort of advertisement for the technology and the PV-system. In addition the attractiveness of the internet appearance of the plant operator rises and the public awareness of such projects could increase. Seen from the user perspective - such an internet project gives private or business users the possibility to inform themselves interactively, purposefully and with the possibility to move through the plant on their own. Users could utilize the guidance through the plant without overcoming far geographical distances, saving time and money. Perhaps this source of information helps awaking a larger consciousness for renewable energies. The result OnToPV showed the various possibilities offered by projects of this kind in the internet. Ideas of possible extensions as for example the integration of current PV-plant operational data or of a virtual learning platform illustrate the perspectives of the project. Virtual guidance of this kind for various types of power plants are conceivable. (orig.)

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

    Science.gov (United States)

    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.

  13. Carotenes in processed tomato after thermal treatment

    NARCIS (Netherlands)

    Luterotti, S.; Bicanic, D.D.; Markovic, K.; Franko, M.

    2015-01-01

    This report adds to the ongoing vivid dispute on the fate of carotenes in tomato upon thermal processing. Although many papers dealing with changes in the raw tomatoes during industrial treatment have already appeared, data on the fate of finished, processed tomato products when they are

  14. λ-Carrageenan Suppresses Tomato Chlorotic Dwarf Viroid (TCDVd Replication and Symptom Expression in Tomatoes

    Directory of Open Access Journals (Sweden)

    Jatinder S. Sangha

    2015-05-01

    Full Text Available The effect of carrageenans on tomato chlorotic dwarf viroid (TCDVd replication and symptom expression was studied. Three-week-old tomato plants were spray-treated with iota(ɩ-, lambda(λ-, and kappa(κ-carrageenan at 1 g·L−1 and inoculated with TCDVd after 48 h. The λ-carrageenan significantly suppressed viroid symptom expression after eight weeks of inoculation, only 28% plants showed distinctive bunchy-top symptoms as compared to the 82% in the control group. Viroid concentration was reduced in the infected shoot cuttings incubated in λ-carrageenan amended growth medium. Proteome analysis revealed that 16 tomato proteins were differentially expressed in the λ-carrageenan treated plants. Jasmonic acid related genes, allene oxide synthase (AOS and lipoxygenase (LOX, were up-regulated in λ-carrageenan treatment during viroid infection. Taken together, our results suggest that λ-carrageenan induced tomato defense against TCDVd, which was partly jasmonic acid (JA dependent, and that it could be explored in plant protection against viroid infection.

  15. PV monitoring at Jubilee Campus - Nottingham University

    Energy Technology Data Exchange (ETDEWEB)

    Riffat, S.B.; Gan, G.

    2002-07-01

    This report summarises the results of a project monitoring the efficiency of photovoltaic (PV) modules integrated in the roofs of atria to meet the energy consumption needs of ventilation fans in the academic buildings at the Jubilee Campus of the University of Nottingham. Details are given of the instrumentation of one atrium to allow the monitoring the effectiveness of the ventilation in cooling the PV arrays integrated in the atrium roof, the economic analysis of the benefit of cooling the PV system, and the use of computational fluid dynamics (CFD) modelling to predict the performance of the atrium. The design of the PV system, the calculated system efficiency, the high cost of atrium integrated PV power supplies, the periodic failure of the inverters, and the overheating of the PV array and the atrium space in the summer are discussed.

  16. Consumer attitudes and preferences for fresh market tomatoes.

    Science.gov (United States)

    Oltman, A E; Jervis, S M; Drake, M A

    2014-10-01

    This study established attractive attributes and consumer desires for fresh tomatoes. Three focus groups (n = 28 participants) were conducted to explore how consumers perceived tomatoes, including how they purchased and consumed them. Subsequently, an Adaptive Choice Based Conjoint (ACBC) survey was conducted to understand consumer preferences toward traditional tomatoes. The ACBC survey with Kano questions (n = 1037 consumers in Raleigh, NC) explored the importance of color, firmness, size, skin, texture, interior, seed presence, flavor, and health benefits. The most important tomato attribute was color, then juice when sliced, followed by size, followed by seed presence, which was at parity with firmness. An attractive tomato was red, firm, medium/small sized, crisp, meaty, juicy, flavorful, and with few seeds. Deviations from these features resulted in a tomato that was rejected by consumers. Segmentations of consumers were determined by patterns in utility scores. External attributes were the main drivers of tomato liking, but different groups of tomato consumers exist with distinct preferences for juiciness, firmness, flavor, and health benefits. Conjoint analysis is a research technique that collects a large amount of data from consumers in a format designed to be reflective of a real life market setting and can be combined with qualitative insight from focus groups to gain information on consumer consumption and purchase behaviors. This study established that the most important fresh tomato attributes were color, amount of juice when sliced, and size. Distinct consumer clusters were differentiated by preference for color/appearance, juiciness and firm texture. Tomato growers can utilize the results to target attributes that drive consumer choice for fresh tomatoes. © 2014 Institute of Food Technologists®

  17. PV-DSM: Policy actions to speed commercialization

    International Nuclear Information System (INIS)

    Hoff, T.; Wenger, H.J.; Keane, D.M.

    1993-01-01

    Pacific Gas and Electric Company (PG ampersand E) recently applied Demand-Side Management (DSM) evaluation techniques to photovoltaic (PV) technology to develop the concept of photovoltaics as a Demand-Side Management option (PV-DSM). The analysis demonstrated that PV-DSM has the potential to be economically attractive. Two criticisms in response to that analysis are that the assumptions of 25 year financing and a 25 year evaluation period are unrealistic. This paper responds to those criticisms and documents the mathematical relationships to calculate the value of PV-DSM from a customer's perspective. It demonstrates how regulatory and government agencies could implement policies to resolve both issues and speed PV commercialization

  18. The possibility of developing hybrid PV/T solar system

    Science.gov (United States)

    Dobrnjac, M.; Zivkovic, P.; Babic, V.

    2017-05-01

    An alternative and cost-effective solution to developing integrated PV system is to use hybrid photovoltaic/thermal (PV/T) solar system. The temperature of PV modules increases due to the absorbed solar radiation that is not converted into electricity, causing a decrease in their efficiency. In hybrid PV/T solar systems the reduction of PV module temperature can be combined with a useful fluid heating. In this paper we present the possibility of developing a new hybrid PV/T solar system. Hybrid PV/T system can provide electrical and thermal energy, thus achieving a higher energy conversion rate of the absorbed solar radiation. We developed PV/T prototype consisted of commercial PV module and thermal panel with our original solution of aluminium absorber with special geometric shapes. The main advantages of our combined PV/T system are: removing of heat from the PV panel; extending the lifetime of photovoltaic cells; excess of the removing heat from PV part is used to heat the fluid in the thermal part of the panel; the possibility of using on the roof and facade constructions because less weight.

  19. Antioxidant Activity from Various Tomato Processing

    Directory of Open Access Journals (Sweden)

    Retno Sri Iswari

    2016-04-01

    Full Text Available Tomato is one of the high antioxidant potential vegetables. Nowadays, there are many techniques of tomato processings instead of fresh consumption, i.e. boiled, steamed, juiced and sauteed. Every treatment of cooking will influence the chemical compound inside the fruits and the body's nutrition intake. It is important to conduct the research on antioxidant compound especially lycopene, β-carotene, vitamin C, α-tocopherol, and its activity after processing. This research has been done using the experimental method. Tomatoes were cooked into six difference ways, and then it was extracted using the same procedure continued with antioxidant measurement. The research results showed that steaming had promoted the higher antioxidant numbers (lycopene. α-tocopherol, β-carotene and vitamin C and higher TCA and antioxidant activities in the tomatoes than other processings. It was indicated that steaming was the best way to enhance amount, capacity and activities of antioxidants of the tomatoes.

  20. Efficacy of the Non-Pathogenic Agrobacterium Strains K84 and K1026 against Crown Gall in Tunisia

    Directory of Open Access Journals (Sweden)

    A. Rhouma

    2004-08-01

    Full Text Available The non-pathogenic Agrobacterium radiobacter strain K84 and its genetically modified (GEM strain K1026 were tested for their effectiveness against local Tunisian strains and two reference strains (C58 and B6 of the crown gall bacterium Agrobacterium tumefaciens. Tests in planta were carried out on herbaceous plants (tomato and tagetes and on some sensitive rootstocks (bitter almond, peach almond hybrid GF677 and quince BA29. In vitro tests showed that both K84 and K1026 were effective and that the difference between these strains was not statistically significant. On tomato and tagetes, strain K84 was effective against all crown gall isolates with the exception of the A. tumefaciens reference strain B6. GEM strain K1026 was very effective against all isolates from Tunisia and against the reference strains. Both antagonistic strains significantly reduced the percentage of galled plants as well as the number of galls per plant. Under field conditions, both antagonists controlled crown gall effectively. Best results were obtained on the bitter almond-tree rootstock. Antagonist effectiveness was less evident on quince BA29 and peach almond GF677 rootstocks. The genetically modified strain K1026 is of interest in controlling crown gall disease in Tunisia.

  1. PV Obelisk - Information system with photovoltaics

    International Nuclear Information System (INIS)

    Ruoss, D.; Rasmussen, J.

    2004-01-01

    This final report for the Swiss Federal Office of Energy (SFOE) describes the development of an information system powered by a photovoltaic (PV) array. As an innovative approach, the 'PV-Obelisk' project is the combination of PV with a multi-functional pillar made of natural stone in an aesthetic way. The PV modules serve both as a power supply and as a design element. Two initial prototypes led the way to a third, optimised consumer configuration that was planned to guarantee maximum user frequency. Test operation in front of the 'Heidiland' motor way restaurant confirmed the market analyses made and delivered the expected results. The product, whose three LCD displays are updated via a mobile telephony-based text-message system, proved its technical reliability and showed a high user frequency. Because of the high overall energy consumption, PV power can only partially contribute to the energy supply needed. Various compromises in the technical and aesthetic areas are discussed that were made for the sake of product acceptance in the market. The range of application areas for such a 'PV Obelisk' are discussed and the need for early co-ordination with urban planners is stressed

  2. Flavor characteristics of the juices from fresh market tomatoes differentiated from those from processing tomatoes by combined analysis of volatile profiles with sensory evaluation.

    Science.gov (United States)

    Iijima, Yoko; Iwasaki, Yumi; Otagiri, Yuji; Tsugawa, Hiroshi; Sato, Tsuneo; Otomo, Hiroe; Sekine, Yukio; Obata, Akio

    2016-12-01

    Various commercial tomato juices with different flavors are available at markets worldwide. To clarify the marker compounds related to the flavor characteristics of tomato juice, we analyzed 15 pure commercial tomato juices by a combination of volatile profiling and sensory evaluation. The correlations among volatiles and the relationship between volatiles and sensory descriptors were elucidated by multivariate analyses. Consequently, the tomato juices made from fresh market tomatoes (including the popular Japanese tomato variety "Momotaro") were clearly separated from other juices made from processing tomatoes, by both the volatile composition and sensory profiles. cis-3-Hexenol, hexanal, and apocarotenoids negatively contributed to the juices from fresh market tomatoes, whereas Strecker aldehydes and furfural showed positive contributions to the juices. Accordingly, the sensory characteristics of juices from fresh market tomatoes were related to cooked and fruity flavors but not to green or fresh notes.

  3. The new NOZ-PV: Market-oriented

    International Nuclear Information System (INIS)

    Ter Horst, E.

    1995-01-01

    In the proposal for the new National Research Program for Photovoltaics (NOZ-PV) 1995-1999 the focus is on four subjects: solar cell technology, the industrial support, the stimulation of autonomous, favorable applications and markets for PV, and the realization of a training program PV in the Built Areas. The program will be carried out as a market-oriented program. 1 tab., 2 figs

  4. Tomato NAC transcription factor SlSRN1 positively regulates defense response against biotic stress but negatively regulates abiotic stress response.

    Directory of Open Access Journals (Sweden)

    Bo Liu

    Full Text Available Biotic and abiotic stresses are major unfavorable factors that affect crop productivity worldwide. NAC proteins comprise a large family of transcription factors that play important roles in plant growth and development as well as in responses to biotic and abiotic stresses. In a virus-induced gene silencing-based screening to identify genes that are involved in defense response against Botrytis cinerea, we identified a tomato NAC gene SlSRN1 (Solanum lycopersicum Stress-related NAC1. SlSRN1 is a plasma membrane-localized protein with transactivation activity in yeast. Expression of SlSRN1 was significantly induced by infection with B. cinerea or Pseudomonas syringae pv. tomato (Pst DC3000, leading to 6-8 folds higher than that in the mock-inoculated plants. Expression of SlSRN1 was also induced by salicylic acid, jasmonic acid and 1-amino cyclopropane-1-carboxylic acid and by drought stress. Silencing of SlSRN1 resulted in increased severity of diseases caused by B. cinerea and Pst DC3000. However, silencing of SlSRN1 resulted in increased tolerance against oxidative and drought stresses. Furthermore, silencing of SlSRN1 accelerated accumulation of reactive oxygen species but attenuated expression of defense genes after infection by B. cinerea. Our results demonstrate that SlSRN1 is a positive regulator of defense response against B. cinerea and Pst DC3000 but is a negative regulator for oxidative and drought stress response in tomato.

  5. Draft Genome Sequence of Bacillus velezensis Lzh-a42, a Plant Growth-Promoting Rhizobacterium Isolated from Tomato Rhizosphere.

    Science.gov (United States)

    Li, Zhenghua; Chen, Mei; Ran, Kun; Wang, Jihua; Zeng, Qiangcheng; Song, Feng

    2018-03-22

    The plant growth-promoting rhizobacterium Bacillus velezensis strain Lzh-a42, which has antimicrobial activity, was isolated from tomato rhizosphere. Here, we report its genome sequence, which includes several predicted functional genes related to secondary metabolite biosynthesis, antimicrobial activity, and biofilm synthesis. Copyright © 2018 Li et al.

  6. Involvement of Trichoderma harzianum Epl-1 Protein in the Regulation of Botrytis Virulence- and Tomato Defense-Related Genes.

    Science.gov (United States)

    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.

  7. Involvement of Trichoderma harzianum Epl-1 Protein in the Regulation of Botrytis Virulence- and Tomato Defense-Related Genes

    Directory of Open Access Journals (Sweden)

    Eriston V. Gomes

    2017-05-01

    Full Text Available 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.

  8. Annual technical report. PV domestic field trial

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-01

    This report describes progress at the first five sites of the UK photovoltaic (PV) domestic field trial. All five sites are generating electricity, but one has not yet been commissioned and two sites are not yet monitoring performance. The BedZED development has roof-mounted PV modules and PV cells installed in sealed double-glazing. Solar slates/tiles have been installed at the Laing Homes development in Montagu Road, where the designer has sought to minimise the visual impact of the PV system on the roofs. At Hunters Moon, PV modules have been retrofitted and some unforeseen difficulties have arisen. PV is an integral part of the roof design at the state-of-the-art low energy development by Integer Houses at Greenfields. Corn Croft uses a British mounting system to facilitate integration of the modules flush with the roof. Installation issues and the progress of the trial are discussed.

  9. Multicompartment analysis of the effects of fertilizing nitrogen form, quantity of potassium fertilizer and tomato variety upon tomato-fruit sugar metabolism

    International Nuclear Information System (INIS)

    Watanabe, Kazuhiko; Mori, Masato; Kubo, Yunosuke; Takeba, Tsuyoshi.

    1977-01-01

    Concerning ''streaky decay'' of tomato fruits, the sugar metabolism of tomato fruits has been studied by multicompartment analysis dividing the radioactivity into 14 C-glucose non-absorbing, ethanol soluble, carbonic acid gas and ethanol insoluble compartments. 14 C-glucose was introduced to pieces of tomato fruits about 60 days after fructification. Influence in the stage of 14 C-glucose entry into the tissue was recognized in a tomato variety affected by excess ammonia and a tomato variety affected by potassium shortage on the carbonic acid gas generation portion. The decrease of metabolism turnover from the ethanol soluble to the insoluble compartment was remarkable in the tomato variety so nutritionally treated as to be apt to cause streaky decay and the variety susceptible to it. (Mori, K.)

  10. PV in a sports arena; PV im Hexenkessel

    Energy Technology Data Exchange (ETDEWEB)

    Hoeche, B.

    2008-05-19

    The German soccer club Werder Bremen is reconstructing its stadium. Apart from higher spectator comfort and a better atmosphere, there will also be PV systems on the roof and external walls of the arena. (orig.)

  11. The PV market - Past, present, and future

    International Nuclear Information System (INIS)

    Hammond, B.

    1992-01-01

    This paper forecasts the photovoltaic (PV) market growth for the 1900's. Ten years of PV history are reviewed and used to establish market trends in terms of average selling price (ASP) and kilowatts shipped by market segment. The market is segmented into indoor consumer, stand-alone, and grid-connected applications. Indoor consumer presently represents a saturated market and is fairly predictable. The stand-alone market (i.e. not connected to the utility grid) is fairly stable and predictable. The utility PV market, however, is highly dependent on a number of market factors such as the cost of conventional energy, the cost of PV systems, utility acceptance of PV, and regulatory controls. Government and institutional regulations, environmental issues, OPEC and Middle East politics will have the greatest impact on the cost of conventional fuels. Private and federal investment in PV technology development could have a significant impact on the cost of PV systems. Forecasts are provided through the year 2000 for indoor consumer, stand-alone, and utility markets. PV has unique attributes which make it a desirable source of energy in specific applications. It is a renewable source of energy, non-polluting, very reliable, predictable, low maintenance, modular, and has a very low operating cost. The energy source (sunlight) is distributed around the globe. Its limitations are high initial cost, no inherent energy storage, and low energy density

  12. Optimal Design of Modern Transformerless PV Inverter Topologies

    DEFF Research Database (Denmark)

    Saridakis, Stefanos; Koutroulis, Eftichios; Blaabjerg, Frede

    2013-01-01

    the operational lifetime period of the PV installation, is also considered in the optimization process. According to the results of the proposed design method, different optimal values of the PV inverter design variables are derived for each PV inverter topology and installation site. The H5, H6, neutral point...... clamped, active-neutral point clamped and conergy-NPC PV inverters designed using the proposed optimization process feature lower levelized cost of generated electricity and lifetime cost, longer mean time between failures and inject more PV-generated energy into the electric grid than their nonoptimized......The design optimization of H5, H6, neutral point clamped, active-neutral point clamped, and conergy-NPC transformerless photovoltaic (PV) inverters is presented in this paper. The components reliability in terms of the corresponding malfunctions, affecting the PV inverter maintenance cost during...

  13. The Clavibacter michiganensis subsp. michiganensis-tomato interactome reveals the perception of pathogen by the host and suggests mechanisms of infection

    Energy Technology Data Exchange (ETDEWEB)

    Savidor, Alon [Tel Aviv University; Teper, [Tel Aviv University; Gartemann, KH [Tel Aviv University; Eichenlaub, R [Tel Aviv University; Chalupowicz, L [Tel Aviv University; Manulis-Sasson, S [Tel Aviv University; Barash, I [Tel Aviv University; Tews, H [Tel Aviv University; Mayer, K [Tel Aviv University; Giannone, Richard J [ORNL; Hettich, Robert {Bob} L [ORNL; Sessa, G [Tel Aviv University

    2012-01-01

    The Gram-positive bacterium Clavibacter michiganensis subsp. michiganensis (Cmm) causes wilt and canker disease of tomato (Solanum lycopersicum). Mechanisms of Cmm pathogenicity and tomato response to Cmm infection are not well understood. To explore the interaction between Cmm and tomato, multidimensional protein identification technology (MudPIT) and tandem mass spectrometry were used to analyze in vitro and in planta generated samples. The results show that during infection Cmm senses the plant environment, transmits signals, induces, and then secretes multiple hydrolytic enzymes, including serine proteases of the Pat-1, Ppa, and Sbt familes, the CelA, XysA, and NagA glycosyl hydrolases, and other cell wall-degrading enzymes. Tomato induction of pathogenesis-related (PR) proteins, LOX1, and other defense-related proteins during infection indicates that the plant senses the invading bacterium and mounts a basal defense response, although partial with some suppressed components including class III peroxidases and a secreted serine peptidase. The tomato ethylene-synthesizing enzyme ACC-oxidase was induced during infection with the wild-type Cmm but not during infection with an endophytic Cmm strain, identifying Cmm-triggered host synthesis of ethylene as an important factor in disease symptom development. The proteomic data were also used to improve Cmm genome annotation, and thousands of Cmm gene models were confirmed or expanded.

  14. PV-HYBRID and MINI-GRID. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    Within the 3rd European Conference at the Centre de Congres in Aix en Provence (France) between 11th and 12th May, 2006, the following lessons were held: (1) Small electric networks: European drivers and projects for the integration of RES and DG into the electricity grids of the future (Manuel Sanchez-Jimenez); (2) PV hybrid system within mini grids - IEA PVPS programme (Meuch Konraf); (3) Renewables for the developing world (Alvaro Ponce Plaza); (4) Rural electicity supply using photovoltaic / - Diesel hybrid systems: Attractive for investors in the renewable energy sector? (Andreas Hahn); (5) Economic analysis of stand-alone and grid-connected photovoltaic systems under current tariff structure of Taiwan (Yaw-Juen Wang); (6) Using wind-PV-diesel hybrid system for electrification of remote village in Western Libya (N.M. Kreama); (7) Venezuela's renewable energy program for small towns and rural areas ''Sembrando Luz'' (Jorge Torres); (8) AeroSmart5, the professional, sysem-compatible small-scale wind energy converter will be tested in field tests (Fabian Jochem); (9) Lifetime, test procedures and recommendations for optimal operating strategies for lead-acid-batteries in renewable energy systems - A survey on results from European projects from the 5th framework programme (Rudi Kaiser); (10) Prototype of a reversible fuel cell system for autonomous power supplies (Tom Smolinska); (11) Interconnection management in microgrids (Michel Vandenbergh); (12) Control strategy for a small-scale stand-alone power system based on renewable energy and hydrogen (Harald Miland); (13) Standard renewable electricity supply for people in rural areas - mini-grids in western provinces of China (Michael Wollny); (14) The Brava island a ''100% renewable energy'' project (Jean-Christian Marcel); (15) Breakthrough to a new era of PV-hybrid systems with the help of standardised components communication? (Michael Mueller); (16) Standardized

  15. Degradation in PV Encapsulation Strength of Attachment: An Interlaboratory Study Towards a Climate-Specific Test

    Energy Technology Data Exchange (ETDEWEB)

    Miller, David; Annigoni, Eleonora; Ballion, Amal; Bokria, Jayesh G.; Bruckman, Laura S.; Burns, David M.; Chen, Xinxin; Feng, Jiangtao; French, Roger H.; Fowler, Sean; Honeker, Christian C.; Kempe, Michael; Khonkar, Hussam; Kohl, Michael; Perret-Aebi, Laure-Emmanuelle; Phillips, Nancy H.; Scott, Kurt P.; Sculati-Meillaud, Fanny; Wohlgemuth, John

    2016-06-06

    Reduced strength of attachment of the encapsulant resulting from the outdoor environment, including ultraviolet (UV) radiation, may decrease photovoltaic (PV) module lifetime by enabling widespread corrosion of internal components. To date, few studies exist showing how the adhesion of PV components varies with environmental stress. We have conducted an interlaboratory experiment to provide an understanding that will be used to develop climatic specific module tests. Factors examined in the study included the UV light source (lamp type), temperature, and humidity to be proposed for use in accelerated aging tests. A poly (ethylene-co-vinyl acetate) (EVA) formulation often used in veteran PV installations was studied using a compressive shear test - to quantify the strength of attachment at the EVA/glass interface. Replicate laminated glass/polymer/glass coupon specimens were weathered at 12 institutions using a variety of indoor chambers or field aging. Shear strength, shear strain, and toughness were measured using a mechanical load-frame for the compressive shear test, with subsequent optical imaging and electron microscopy of the separated surfaces.

  16. Environmental impact of PV cell waste scenario.

    Science.gov (United States)

    Bogacka, M; Pikoń, K; Landrat, M

    2017-12-01

    Rapid growth of the volume of waste from PV cells is expected in the following years. The problem of its utilization seems to be the most important issue for future waste management systems. The environmental impacts of the PV recycling scenario are presented in the manuscript. The analysis is based on the LCA approach and the average data available in specialized databases for silicon standard PV cell is used. The functional unit includes parameters like: efficiency, composition, surface area. The discussion on the environmental impact change due to the location of the PV production and waste processing plants is presented in the manuscript. Additionally, the discussion on the environmental effect of substituting different energy resources with PV cells is presented in the manuscript. The analysis of the PV cell life cycle scenario presented in the article was performed using the SIMA PRO software and data from Ecoinvent 3.0 database together with additional data obtained from other sources. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Novel laboratory mouse papillomavirus (MusPV) infection.

    Science.gov (United States)

    Ingle, A; Ghim, S; Joh, J; Chepkoech, I; Bennett Jenson, A; Sundberg, J P

    2011-03-01

    Most papillomaviruses (PVs) are oncogenic. There are at least 100 different human PVs and 65 nonhuman vertebrate hosts, including wild rodents, which have species-specific PV infections. Florid papillomatosis arose in a colony of NMRI-Foxn1(nu)/Foxn1(nu) (nude) mice at the Advanced Centre for Treatment Research and Education in Cancer in India. Lesions appeared at the mucocutaneous junctions of the nose and mouth. Histologically, lesions were classical papillomas with epidermal hyperplasia on thin fibrovascular stalks in a verrucous pattern. Koilocytotic cells were observed in the stratum granulosum of the papillomatous lesions. Immunohistochemically, these abnormal cells were positive for PV group-specific antigens. With transmission electron microscopy, virus particles were observed in crystalline intranuclear inclusions within keratinocytes. The presence of a mouse PV, designated MusPV, was confirmed by amplification of PV DNA with degenerative primers specific for PVs. This report is the first of a PV and its related disease in laboratory mice.

  18. PV Working with Industry, 2nd Quarter, 2000

    Energy Technology Data Exchange (ETDEWEB)

    Poole, L.; Moon, S.

    2000-06-29

    NREL PV Working With Industry is a quarterly newsletter devoted to the research, development, and deployment performed by NREL staff in concert with their industry and university partners. The Second Quarter, 2000, issue is titled ``Our Shared PV Future''. It contains a review of several important PV-related meetings held in the prior three months: the NCPV Program Review, the 16 European PV Conference, and year-2000 Earth Day activities in Denver, CO. The editorialist is Paul Maycock, Publisher of PV News.

  19. Efficacy of integrated treatment of UV light and low dose gamma irradiation on Escherichia coli O157:H7 and Salmonella enterica on grape tomatoes

    Science.gov (United States)

    Efficacy of integrated treatment of UVC and low dose Gamma irradiation to inactivate mixed Strains of Escherichia coli O157:H7 and Salmonella enterica inoculated on whole Grape tomatoes was evaluated. A mixed bacterial cocktail composed of a three strain mixture of E. coli O157:H7 (C9490, E02128 an...

  20. Screening of tomato genotypes for resistance to tomato fruit borer (helicoverpa armiger hubner) in Pakistan

    International Nuclear Information System (INIS)

    Sajjad, M.; Ashfaq, M.; Suhail, A.

    2011-01-01

    Tomato genotypes viz., Roma Local, Rio Grande, Tanja, Chico III, Long Tipped, Red-Top, FS-8001, FS-8002, Tropic, Pakit, Peelo, NARC-1, Roma VFN, Pant Bahr, Ebein, Nova Mech, Rockingham, Nagina, Shalkot-96, Pomodoro, Manik, Gressilesse, Nadir, Early Mech, Tommy, Pusha Rubi, Tropic boy, Big Long, Sahil, Sun 6002, Money-Maker and Royesta were evaluated to screen out the suitable resistant/susceptible genotypes against the fruit borer in Pakistan. The results imparted that the percentage of fruit infestation and larval population per plant on tested genotypes of tomato varied significantly. Roma VF, NARC-1 and FS-8002 were categorized as susceptible genotypes with fruit infestation (37.69%, 37.08% and 36.41%, respectively) and larval population per plant (1.02%, 1.02% and 0.84 %, respectively). Whereas, the genotypes Sahil, Pakit and Nova Mecb had fruit infestation (12.30%, 13.14% and 13.96%, respectively) and larval population per plant (0.42%, 0.42% and 0.43%, respectively) and declared as resistant genotypes to tomato fruit borer. Lower values of host plant susceptibility indices (HPSI) were recorded on resistant genotypes. Sahil, Pakit and Nova Mecb could be used as a source of resistance for developing tomato genotypes resistant to tomato fruit borer. (author)

  1. The effector repertoire of Fusarium oxysporum determines the tomato xylem proteome composition following infection

    Directory of Open Access Journals (Sweden)

    Fleur eGawehns

    2015-11-01

    Full Text Available Plant pathogens secrete small proteins, of which some are effectors that promote infection. During colonization of the tomato xylem vessels the fungus Fusarium oxysporum f. sp. lycopersici (Fol secretes small proteins that are referred to as SIX (Secreted In Xylem proteins. Of these, Six1 (Avr3, Six3 (Avr2, Six5 and Six6 are required for full virulence, denoting them as effectors. To investigate their activities in the plant, the xylem sap proteome of plants inoculated with Fol wild-type or either AVR2, AVR3, SIX2, SIX5 or SIX6 knockout strains was analyzed with nano-Liquid Chromatography-Mass Spectrometry (nLC-MSMS. Compared to mock-inoculated sap 12 additional plant proteins appeared while 45 proteins were no longer detectable in the xylem sap of Fol-infected plants. Of the 285 proteins found in both uninfected and infected plants the abundance of 258 proteins changed significantly following infection. The xylem sap proteome of plants infected with four Fol effector knockout strains differed significantly from plants infected with wild-type Fol, while that of the SIX2-knockout inoculated plants remained unchanged. Besides an altered abundance of a core set of 24 differentially accumulated proteins (DAPs, each of the four effector knockout strains affected specifically the abundance of a subset of DAPs. Hence, Fol effectors have both unique and shared effects on the composition of the tomato xylem sap proteome.

  2. Grid Integrated Distributed PV (GridPV) Version 2.

    Energy Technology Data Exchange (ETDEWEB)

    Reno, Matthew J.; Coogan, Kyle

    2014-12-01

    This manual provides the documentation of the MATLAB toolbox of functions for using OpenDSS to simulate the impact of solar energy on the distribution system. The majority of the functio ns are useful for interfacing OpenDSS and MATLAB, and they are of generic use for commanding OpenDSS from MATLAB and retrieving information from simulations. A set of functions is also included for modeling PV plant output and setting up the PV plant in th e OpenDSS simulation. The toolbox contains functions for modeling the OpenDSS distribution feeder on satellite images with GPS coordinates. Finally, example simulations functions are included to show potential uses of the toolbox functions. Each function i n the toolbox is documented with the function use syntax, full description, function input list, function output list, example use, and example output.

  3. Screening of tomato varieties for fruit tree based Agroforestry system

    OpenAIRE

    J. Hossain

    2014-01-01

    An experiment was conducted with four tomato varieties under a six year old orchard was accomplished at the Bangabandhu Sheikh Mujibur Rahman Agricultural University (BSMRAU) research farm during October 2011 to April 2012. The experiment was laid out in a Randomized Complete Block Design with three replications. Four tomato varieties (BARI Tomato 2, BARI Tomato 8, BARI Tomato 14 and BARI Tomato 15) were grown under guava, mango, olive and control. Results showed that light availability in co...

  4. 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.

    Science.gov (United States)

    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.

  5. Flexible packaging for PV modules

    Science.gov (United States)

    Dhere, Neelkanth G.

    2008-08-01

    Economic, flexible packages that provide needed level of protection to organic and some other PV cells over >25-years have not yet been developed. However, flexible packaging is essential in niche large-scale applications. Typical configuration used in flexible photovoltaic (PV) module packaging is transparent frontsheet/encapsulant/PV cells/flexible substrate. Besides flexibility of various components, the solder bonds should also be flexible and resistant to fatigue due to cyclic loading. Flexible front sheets should provide optical transparency, mechanical protection, scratch resistance, dielectric isolation, water resistance, UV stability and adhesion to encapsulant. Examples are Tefzel, Tedlar and Silicone. Dirt can get embedded in soft layers such as silicone and obscure light. Water vapor transmittance rate (WVTR) of polymer films used in the food packaging industry as moisture barriers are ~0.05 g/(m2.day) under ambient conditions. In comparison, light emitting diodes employ packaging components that have WVTR of ~10-6 g/(m2.day). WVTR of polymer sheets can be improved by coating them with dense inorganic/organic multilayers. Ethylene vinyl acetate, an amorphous copolymer used predominantly by the PV industry has very high O2 and H2O diffusivity. Quaternary carbon chains (such as acetate) in a polymer lead to cleavage and loss of adhesional strength at relatively low exposures. Reactivity of PV module components increases in presence of O2 and H2O. Adhesional strength degrades due to the breakdown of structure of polymer by reactive, free radicals formed by high-energy radiation. Free radical formation in polymers is reduced when the aromatic rings are attached at regular intervals. This paper will review flexible packaging for PV modules.

  6. Interharmonics from Grid-Connected PV Systems

    DEFF Research Database (Denmark)

    Sangwongwanich, Ariya; Yang, Yongheng; Sera, Dezso

    2017-01-01

    As the penetration level of grid-connected Photovoltaic (PV) systems increases, the power quality is one of the major concerns for system operators and the demands are becoming even stricter. The impact of interharmonics on the grid has been acknowledged in recent research when considering a large......-scale adoption of PV inverters. However, the origins of interharmonics remain unclear. Thus, this paper performs tests on a commercial PV inverter to explore interharmonic generation and more important investigates the mechanism of interharmonic emission. The investigation reveals that the perturbation...... of the solutions. Simulation results indicate that the constant-voltage MPPT method is the most suitable solution to the mitigation of interharmonics introduced by the MPPT operation, as it avoids the perturbation in the PV voltage during operation....

  7. Optimal Solar PV Arrays Integration for Distributed Generation

    Energy Technology Data Exchange (ETDEWEB)

    Omitaomu, Olufemi A [ORNL; Li, Xueping [University of Tennessee, Knoxville (UTK)

    2012-01-01

    Solar photovoltaic (PV) systems hold great potential for distributed energy generation by installing PV panels on rooftops of residential and commercial buildings. Yet challenges arise along with the variability and non-dispatchability of the PV systems that affect the stability of the grid and the economics of the PV system. This paper investigates the integration of PV arrays for distributed generation applications by identifying a combination of buildings that will maximize solar energy output and minimize system variability. Particularly, we propose mean-variance optimization models to choose suitable rooftops for PV integration based on Markowitz mean-variance portfolio selection model. We further introduce quantity and cardinality constraints to result in a mixed integer quadratic programming problem. Case studies based on real data are presented. An efficient frontier is obtained for sample data that allows decision makers to choose a desired solar energy generation level with a comfortable variability tolerance level. Sensitivity analysis is conducted to show the tradeoffs between solar PV energy generation potential and variability.

  8. Commercialization of PV-powered pumping systems for use in utility PV service programs. Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    The project described in this report was a commercialization effort focused on cost-effective remote water pumping systems for use in utility-based photovoltaic (PV) service programs. The project combined a commercialization strategy tailored specifically for electric utilities with the development of a PV-powered pumping system that operates conventional ac pumps rather than relying on the more expensive and less reliable PV pumps on the market. By combining these two attributes, a project goal was established of creating sustained utility purchases of 250 PV-powered water pumping systems per year. The results of each of these tasks are presented in two parts contained in this Final Summary Report. The first part summarizes the results of the Photovoltaic Services Network (PSN) as a new business venture, while the second part summarizes the results of the Golden Photon system installations. Specifically, results and photographs from each of the system installations are presented in this latter part.

  9. Reaction of common bean lines to Xanthomonas axonopodis pv. phaseoli and Curtobacterium flaccumfaciens pv. flaccumfaciens

    Directory of Open Access Journals (Sweden)

    Tamires Ribeiro

    2016-12-01

    Full Text Available The aim of this study was to evaluate the resistance of 58 common bean lines against common bacterial blight (Xanthomonas axonopodis pv. phaseoli and bacterial wilt (Curtobacterium flaccumfaciens pv. flaccumfaciens. The experimental design consisted of completely randomized blocks, with four replications per pathogen. The results were subjected to variance analysis by the F test at 1% probability. Significant differences between the treatments indicated different resistance levels among the lines against both pathogens. According to the Scott-Knott test, six lines were resistant to Xanthomonas axonopodis pv. phaseoli, 14 moderately resistant, and 38 susceptible. To Curtobacterium flaccumfaciens pv. flaccumfaciens, 11 lines were resistant, 26 moderately resistant and 21 susceptible. Among these, the lines Pr10-3-4/1, Pr10-5-2/1 and Pr10-5- 2/2 of the black bean group and C10-2-4/2 of the Carioca group were resistant to both major bacterial diseases affecting common bean in Brazil.

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

    Science.gov (United States)

    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.

  11. Alleviating salt stress in tomato inoculated with mycorrhizae: Photosynthetic performance and enzymatic antioxidants

    Directory of Open Access Journals (Sweden)

    Mohsen K.H. Ebrahim

    2017-11-01

    Full Text Available Tomato cultivars (Sultana-7 & Super Strain-B were germinated with various concentrations (0–200 mM of NaCl. Seed germination in the Super Strain-B was promoted by 25 mM NaCl. However, the germination of both cultivars was progressively inhibited by 50 and 100 mM NaCl and obstructed at 200 mM NaCl, and this response was more pronounced for Sultana-7. Therefore, Super Strain-B was selected for further investigation, such as growth under NaCl stress (50 & 100 mM and inoculation with vesicular-arbuscular mycorrhizal fungus (Glomus fasciculatum, VAMF. The leaves of Super Strain-B showed reduced mineral (N, P, K, Mg uptake and K/Na ratio as well as increased Na uptake and N/P ratio in response to salinity. Moreover, salinity decreased the chlorophyll (Chl contents coupled with an increase in Chl a/b, Hill-reaction activity, and quenched Chl a fluorescence emission. These changes reflect a disturbance in the structure, composition and function of the photosynthetic apparatus as well as the activity of photosystem 2. The superoxide dismutase and peroxidase activities of leaves were enhanced by salinity, whereas the catalase activity was decreased. Leaf polysaccharides and proteins as well as shoot biomass also decreased as a result of salinity, but the total soluble sugars and root to shoot ratio improved.VAMF enhanced both the photosynthesis and productivity of plants; thus, VAMF may alleviate the adverse effects of salinity in plants by increasing their salt tolerance. Although mycorrhizal infection showed a negative correlation with salinity, it remained relatively high (21 & 25% at 100 mM NaCl. Keywords: Mycorrhizae, tomato, salinity, minerals, photosynthetic performance and antioxidant enzymes

  12. A Practical Irradiance Model for Bifacial PV Modules: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Marion, Bill; MacAlpine, Sara; Deline, Chris; Asgharzadeh, Amir; Toor, Fatima; Riley, Daniel; Stein, Joshua; Hansen, Clifford

    2017-06-15

    A model, suitable for a row or multiple rows of photovoltaic (PV) modules, is presented for estimating the backside irradiance for bifacial PV modules. The model, which includes the effects of shading by the PV rows, is based on the use of configuration factors (CFs) to determine the fraction of a source of irradiance that is received by the backside of the PV module. Backside irradiances are modeled along the sloped height of the PV module, but assumed not to vary along the length of the PV row. The backside irradiances are corrected for angle-of-incidence losses and may be added to the front side irradiance to determine the total irradiance resource for the PV cell. Model results are compared with the measured backside irradiances for NREL and Sandia PV systems, and with results when using the RADIANCE ray tracing program.

  13. Multifunctional a-Si PV systems

    Energy Technology Data Exchange (ETDEWEB)

    Peippo, K; Lund, P; Vartiainen, E [Helsinki Univ. of Technology, Otaniemi (Finland). Advanced Energy Systems

    1998-10-01

    The optimal use of the various forms of solar energy (passive, active, daylighting, photovoltaics) in buildings calls for an optimal integration of the technologies. As energy conservation potential in space heating may soon be exhausted, electricity efficiency and on-site generation will play an increasing role in energy-conscious building design. There, dispersed PV systems integrated into buildings show a significant market potential, due to a number of benefits: no extra land area is required, PV-array may replace conventional cladding materials and become a building element. Moreover, the produced PV-electricity is more valuable for the building owner than for an electric utility

  14. Industrial processing versus home processing of tomato sauce

    NARCIS (Netherlands)

    Tomas, Merve; Beekwilder, Jules; Hall, Robert D.; Sagdic, Osman; Boyacioglu, Dilek; Capanoglu, Esra

    2017-01-01

    The effect of industrial and home processing, in vitro gastrointestinal digestion, individual phenolic content, and antioxidant capacity of tomato into tomato sauce were investigated. Industrial processing of tomato fruit into sauce had an overall positive effect on the total antioxidant capacity

  15. Preferential Promotion of Lycopersicon esculentum (Tomato) Growth by Plant Growth Promoting Bacteria Associated with Tomato.

    Science.gov (United States)

    Vaikuntapu, Papa Rao; Dutta, Swarnalee; Samudrala, Ram Babu; Rao, Vukanti R V N; Kalam, Sadaf; Podile, Appa Rao

    2014-12-01

    A total of 74 morphologically distinct bacterial colonies were selected during isolation of bacteria from different parts of tomato plant (rhizoplane, phylloplane and rhizosphere) as well as nearby bulk soil. The isolates were screened for plant growth promoting (PGP) traits such as production of indole acetic acid, siderophore, chitinase and hydrogen cyanide as well as phosphate solubilization. Seven isolates viz., NR4, NR6, RP3, PP1, RS4, RP6 and NR1 that exhibited multiple PGP traits were identified, based on morphological, biochemical and 16S rRNA gene sequence analysis, as species that belonged to four genera Aeromonas, Pseudomonas, Bacillus and Enterobacter. All the seven isolates were positive for 1-aminocyclopropane-1-carboxylate deaminase. Isolate NR6 was antagonistic to Fusarium solani and Fusarium moniliforme, and both PP1 and RP6 isolates were antagonistic to F. moniliforme. Except RP6, all isolates adhered significantly to glass surface suggestive of biofilm formation. Seed bacterization of tomato, groundnut, sorghum and chickpea with the seven bacterial isolates resulted in varied growth response in laboratory assay on half strength Murashige and Skoog medium. Most of the tomato isolates positively influenced tomato growth. The growth response was either neutral or negative with groundnut, sorghum and chickpea. Overall, the results suggested that bacteria with PGP traits do not positively influence the growth of all plants, and certain PGP bacteria may exhibit host-specificity. Among the isolates that positively influenced growth of tomato (NR1, RP3, PP1, RS4 and RP6) only RS4 was isolated from tomato rhizosphere. Therefore, the best PGP bacteria can also be isolated from zones other than rhizosphere or rhizoplane of a plant.

  16. Tomato SlRbohB, a member of the NADPH oxidase family, is required for disease resistance against Botrytis cinerea and tolerance to drought stress

    Directory of Open Access Journals (Sweden)

    Xiaohui eLi

    2015-06-01

    Full Text Available NADPH oxidases (also known as respiratory burst oxidase homologues, Rbohs are the enzymes that catalyze the generation of reactive oxygen species (ROS in plants. In the present study, eight SlRboh genes were identified in tomato and their possible involvement in resistance to Botrytis cinerea and drought tolerance was examined. Expression of SlRbohs was induced by B. cinerea and Pseudomonas syringae pv. tomato but displayed distinct patterns. Virus-induced gene silencing (VIGS-based silencing of SlRbohB resulted in reduced resistance to B. cinerea but silencing of each of other SlRbohs did not affect the resistance. The SlRbohB-silenced plants accumulated more ROS and attenuated expression of defense genes after infection of B. cinerea than the nonsilenced plants. Silencing of SlRbohB also suppressed flg22-induced ROS burst and the expression of SlLrr22, a marker gene related to PAMP-triggered immunity (PTI. Transient expression of SlRbohB in Nicotiana benthamiana led to enhanced resistance to B. cinerea. Furthermore, silencing of SlRbohB resulted in decreased drought tolerance, accelerated water loss in leaves and altered expression of drought-responsive genes. Our data demonstrate that SlRbohB positively regulates the resistance to B. cinerea, flg22-induced PTI and drought tolerance in tomato.

  17. Induction of mutations in tomato variety Solar Set

    International Nuclear Information System (INIS)

    Peiris, R.

    1995-01-01

    The production of tomatoes in Sri Lanka is hampered by many problems. Tomato is an economic crop which is nutritious and has export potential. The major constraint for tomato production is Bacterial Wilt caused by Pseudomonas Solanacearum. A study was initiated with the obnjective of finding tomato genotype having resistance to bacterial wilt. The seeds of the varity, Solar Set which is highly susceptible to bacterial wilt was exposed to irradiation from Co 60 source after adjusting moisture content to 14%. The dosese given were 0, 25, 30, 35, 40, 45, 50 krad. The seeds were sown in plastic trays and germination count was taken after 3 days. The LD50 value for the induction of mutants in tomato variety Solar Set is observed to be 35.6 Kr and it is the best dose value for the induction of beneficial mutants in tomato variety, Solar Set by irradiation

  18. Effect of gamma irradiation on fatty acids of tomato seed oil

    International Nuclear Information System (INIS)

    El-Sayed, S.A.; Raouf, M.S.; Morad, M.M.; Rady, A.H.

    1979-01-01

    Since gamma irradiation of tomatoes is investigated as a tool for increasing tomato shelf-lefe, in this study the tomato seed oil produced from irradiated tomatoes was compared with that produced from industrial tomato seeds and with cotton seeds. Fatty acid contents of tomato seed oil, produced from industrial tomato seed waste and from tomato seeds (Variety Ace), were found nearly the same as in the edible cotton seed oil. Hence, both tomato seed oils may be considered as an additional source of essential fatty acids especially linoleic. Gamma irradiation doses ranged from 50-200 Krad had no significant effect on total saturated and total unsaturated fatty acids. 200 Krad led to significant increases in lenolic acid on the account of insignificant decrease in palmatic acid. Essentail and non essential amino acids of tomato seed meal seem to be equivalent to these of cotton seed meal. This suggests the possible use of tomato seed meal in animal feeding

  19. Simultaneous and individual quantitative estimation of Salmonella, Shigella and Listeria monocytogenes on inoculated Roma tomatoes (Lycopersicon esculentum var. Pyriforme) and Serrano peppers (Capsicum annuum) using an MPN technique.

    Science.gov (United States)

    Cabrera-Díaz, E; Martínez-Chávez, L; Sánchez-Camarena, J; Muñiz-Flores, J A; Castillo, A; Gutiérrez-González, P; Arvizu-Medrano, S M; González-Aguilar, D G; Martínez-Gonzáles, N E

    2018-08-01

    Simultaneous and individual enumeration of Salmonella, Shigella and Listeria monocytogenes was compared on inoculated Roma tomatoes and Serrano peppers using an Most Probable Number (MPN) technique. Samples consisting of tomatoes (4 units) or peppers (8 units) were individually inoculated with a cocktail of three strains of Salmonella, Shigella or L. monocytogenes, or by simultaneous inoculation of three strains of each pathogen, at low (1.2-1.7 log CFU/sample) and high (2.2-2.7 log CFU/sample) inocula. Samples were analyzed by an MPN technique using universal pre-enrichment (UP) broth at 35 °C for 24 ± 2 h. The UP tubes from each MPN series were transferred to enrichment and plating media following adequate conventional methods for isolating each pathogen. Data were analyzed using multifactorial analysis of variance (p  simultaneous), type of bacteria (Salmonella > Shigella and L. monocytogenes), type of sample (UP broth > pepper and tomato), and inoculum level (high > low). The MPN technique was effective for Salmonella on both commodities. Shigella counts were higher on tomatoes compared to peppers, (p < 0.05), and for L. monocytogenes on peppers (p < 0.05). Copyright © 2018 Elsevier Ltd. All rights reserved.

  20. PV installations, protection and the code

    Energy Technology Data Exchange (ETDEWEB)

    Silecky, L. [Mersen, Toronto, ON (Canada)

    2010-12-15

    This article discussed the need for improved standards in Ontario's solar industry to ensure safety for the systems and also safety for the workers. Photovoltaic cells used in solar arrays can now deliver between 50 vDC to 600 vDC. The workings of such a high voltage photocell must be understood in order to understand its protection needs. Since PVs are semiconductors and susceptible to damage from short circuits and overloads, a fast-acting overcurrent protective device (OCPD) should be used. Combiner boxes are also needed to provide a clean method of safely connecting all the wires that are needed in the system, including surge protection and a means of isolation between the PV array and the inverter. Section 50 of the Canadian Electrical Code outlines the requirements for solar PV systems, but it does not mention the protection of DC circuits, including DC fuse protectors which are manufactured to provide a high degree of protection for the PV array. As the photovoltaic (PV) market continues to grow in Ontario, the PV industry also has a responsibility to ensure it is in compliance with codes and standards related to photovoltaic systems. This author suggested that Article 690 of the National Electric Code (NEC) is a good document to use when determining the requirements for PV systems. 3 figs.

  1. Comparative transcriptome profiling of a resistant vs. susceptible tomato (Solanum lycopersicum cultivar in response to infection by tomato yellow leaf curl virus.

    Directory of Open Access Journals (Sweden)

    Tianzi Chen

    Full Text Available Tomato yellow leaf curl virus (TYLCV threatens tomato production worldwide by causing leaf yellowing, leaf curling, plant stunting and flower abscission. The current understanding of the host plant defense response to this virus is very limited. Using whole transcriptome sequencing, we analyzed the differential gene expression in response to TYLCV infection in the TYLCV-resistant tomato breeding line CLN2777A (R and TYLCV-susceptible tomato breeding line TMXA48-4-0 (S. The mixed inoculated samples from 3, 5 and 7 day post inoculation (dpi were compared to non-inoculated samples at 0 dpi. Of the total of 34831 mapped transcripts, 209 and 809 genes were differentially expressed in the R and S tomato line, respectively. The proportion of up-regulated differentially expressed genes (DEGs in the R tomato line (58.37% was higher than that in the S line (9.17%. Gene ontology (GO analyses revealed that similar GO terms existed in both DEGs of R and S lines; however, some sets of defense related genes and their expression levels were not similar between the two tomato lines. Genes encoding for WRKY transcriptional factors, R genes, protein kinases and receptor (-like kinases which were identified as down-regulated DEGs in the S line were up-regulated or not differentially expressed in the R line. The up-regulated DEGs in the R tomato line revealed the defense response of tomato to TYLCV infection was characterized by the induction and regulation of a series of genes involved in cell wall reorganization, transcriptional regulation, defense response, ubiquitination, metabolite synthesis and so on. The present study provides insights into various reactions underlining the successful establishment of resistance to TYLCV in the R tomato line, and helps in the identification of important defense-related genes in tomato for TYLCV disease management.

  2. Experimental grid connected PV system power analysis

    Science.gov (United States)

    Semaoui, Smail; Abdeladim, Kamel; Arab, Amar Hadj; Boulahchich, Saliha; Amrouche, Said Ould; Yassaa, Noureddine

    2018-05-01

    Almost 80 % of Algerian territory is appropriate for the exploitation of solar energy. The Algerian energetic strategy provides a substantial injection of PV electricity to the national grid. Currently, about 344 MWp of PV arrays which corresponds approximately to 2,34 km2 of module surfaces, are connected on electricity grid over the national territory. The Algerian Northern regions are characterized by strong pollution and high humidity. These phenomena affect the energetic productivity of PV generator. The objective of our study is to analyze experimental grid connected PV system power in coastal locations. Hence, experiments have been conducted on three identical PV systems to determine the electrical performances. Transformer-less inverters are the most attractive for the ground-based photovoltaic (PV) system due to their efficiencies, reduced cost and weight. Besides, the absence of the galvanic isolation generates problems of capacitive leakage current on the AC side and the degradation of the insulation resistance on the DC side of the inverter. In this work, experimental study of the behavior of single-phase inverters without transformers is presented. The main objective of this work is to study the degradation of the insulation resistance at the input of the inverter, and the capacitive leakage current at the output of the inverter. This study was achieved at the CDER on a rainy day of 15/03/2017, on the first PV plant connected to the low voltage network in Algeria. This investigation can help forecasting the PV array energetic production by taking into account natural conditions.

  3. Management of Meloidogyne incognita on tomato with endophytic bacteria and fresh residue of Wasabia japonica.

    Science.gov (United States)

    Li, G J; Dong, Q E; Ma, L; Huang, Y; Zhu, M L; Ji, Y P; Wang, Q H; Mo, M H; Zhang, K Q

    2014-10-01

    To characterize the nematicidal endophytic bacteria (NEB) of Wasabia japonica (wasabi) and evaluated the control efficacies of promising NEB as well as fresh wasabi residue (FWR) against Meloidogyne incognita on tomato. By in vitro bioassay, 53 NEB strains showing nematicidal efficacies of >50% against J2 of M. incognita were isolated from wasabi. Basing on 16S rRNA gene sequences, these NEB were identified into 18 species of 11 genera. In greenhouse, incorporation of selected NEB culture or FWR into potted soil significantly reduced infection of M. incognita on tomato. Treating tomatoes with either FWR or NEB of Raoultella terrigena RN16 and Pseudomonas reinekei SN21 in the field yielded excellent control efficacies against M. incognita, especially the combinations of FWR with either R. terrigena RN16 or Ps. reinekei SN21 at doses of 50 g plus 100 ml per plant or more. The results established that R. terrigena RN16 and Ps. reinekei SN21 applied separately or combined with FWR have the potential to provide bioprotection agents against M. incognita. This study provides novel way for disease management using combination of endophyte and host residue. © 2014 The Society for Applied Microbiology.

  4. Effects of pre-sowing gamma irradiation of tomato seeds on production and yield of open field tomato crops

    International Nuclear Information System (INIS)

    Zhamyansurehn, D.; Voloozh, D.

    1976-01-01

    The following conclusions may be drawn from results obtained in experiments with pre-sowing irradiation of tomato seeds and its effect on tomato crops. The dose of 2500 R proved to be optimum for increase of tomato crops yield. The yield increase resulted from increase in average weight, quantity and the dry matter of the fruit. The irradiation did not significantly affect the concentration of sugar, phosphorus, nitrogen and ascorbic acid in the fruit. (author)

  5. Effects of pre-sowing gamma irradiation of tomato seeds on production and yield of open field tomato crops

    Energy Technology Data Exchange (ETDEWEB)

    Zhamyansurehn, D [Institut Fiziki i Matematiki Akademii Nauk Mongol' skoj Narodnoj Respubliki, Ulan Bator; Voloozh, D

    1976-01-01

    The following conclusions may be drawn from results obtained in experiments with pre-sowing irradiation of tomato seeds and its effect on tomato crops. The dose of 2500 R proved to be optimum for increase of tomato crops yield. The yield increase resulted from increase in average weight, quantity and the dry matter of the fruit. The irradiation did not significantly affect the concentration of sugar, phosphorus, nitrogen and ascorbic acid in the fruit.

  6. China PV Business and Applications Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Sherring, Chris (Sherring Energy Associates)

    1999-08-30

    This report provides an overview of photovoltaics (PV) business and applications in China. Although more than 70 million people in China are without access to grid electricity, many of the unelectrified regions benefit from considerable renewable resources, including good solar insolation. Current annual PV sales are still modest, however, and are estimated to be between 2.0 and 2.5 megawatts. This and other significant PV data, including information regarding the current status of key aspects of Chinese businesses, markets, and distribution channels, are included in the report. Detailed company profiles of Chinese business organizations and summaries of visits made to these companies (as well as to more remote sites in Inner Mongolia to examine PV usage by the end-use customer) in September-October 1998 are also presented.

  7. Robust PV Degradation Methodology and Application

    Energy Technology Data Exchange (ETDEWEB)

    Jordan, Dirk [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Deline, Christopher A [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Kurtz, Sarah [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Kimball, Greg [SunPower; Anderson, Mike [SunPower

    2017-11-15

    The degradation rate plays an important role in predicting and assessing the long-term energy generation of PV systems. Many methods have been proposed for extracting the degradation rate from operational data of PV systems, but most of the published approaches are susceptible to bias due to inverter clipping, module soiling, temporary outages, seasonality, and sensor degradation. In this manuscript, we propose a methodology for determining PV degradation leveraging available modeled clear-sky irradiance data rather than site sensor data, and a robust year-over-year (YOY) rate calculation. We show the method to provide reliable degradation rate estimates even in the case of sensor drift, data shifts, and soiling. Compared with alternate methods, we demonstrate that the proposed method delivers the lowest uncertainty in degradation rate estimates for a fleet of 486 PV systems.

  8. A single base pair in the right terminal domain of Tomato planta macho viroid is a virulence determinant factor on tomato

    Science.gov (United States)

    Tomato planta macho viroid (TPMVd), including isolates previously designated as Mexican papita viroid (MPVd), causes serious disease on tomatoes in North America. Two predominant variants, sharing 93.8% sequence identity, incited distinct severe (MPVd-S) or mild (MPVd-M) symptoms on tomato. To ide...

  9. Plant-mediated restriction of Salmonella enterica on tomato and spinach leaves colonized with Pseudomonas plant growth-promoting rhizobacteria.

    Science.gov (United States)

    Hsu, Chiun-Kang; Micallef, Shirley A

    2017-10-16

    Reducing Salmonella enterica association with plants during crop production could reduce risks of fresh produce-borne salmonellosis. Plant growth-promoting rhizobacteria (PGPR) colonizing plant roots are capable of promoting plant growth and boosting resistance to disease, but the effects of PGPR on human pathogen-plant associations are not known. Two root-colonizing Pseudomonas strains S2 and S4 were investigated in spinach, lettuce and tomato for their plant growth-promoting properties and their influence on leaf populations of S. enterica serovar Newport. Plant roots were inoculated with Pseudomonas in the seedling stage. At four (tomato) and six (spinach and lettuce) weeks post-germination, plant growth promotion was assessed by shoot dry weight (SDW) and leaf chlorophyll content measurements. Leaf populations of S. Newport were measured after 24h of leaf inoculation with this pathogen by direct plate counts on Tryptic Soy Agar. Root inoculation of spinach cv. 'Tyee', with Pseudomonas strain S2 or S4 resulted in a 69% and 63% increase in SDW compared to non-inoculated controls (pgrowth by over 40% compared to controls (pgrowth promotion was detected in tomato cv. 'BHN602', but S2-inoculated plants had elevated leaf chlorophyll content (13%, pgrowth, but also reduce the fitness of epiphytic S. enterica in the phyllosphere. Plant-mediated effects induced by PGPR may be an effective strategy to minimize contamination of crops with S. enterica during cultivation. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Effect of tomato post-harvest fungicide treatment and storage conditions on the quality of fruits, and biological value of tomato pulp and concentrated pulp

    Directory of Open Access Journals (Sweden)

    H. Parynow

    2013-12-01

    Full Text Available The influence of storage conditions on the quality of tomato fruits was tested. The rate of ripening was established in normal air, where tomatoes ripen quickly, under controlled atmosphere where they ripen more slowly and under low pressure, where they ripen slowest. The influence of post-harvest benomyl or methylthiophanate treatment on tomato rot, ripening, and biological value were examined. Post-harvest tomato treatment did not reduce fruit rot. The color of fruits and the processed products depended on the fungicide treatment. Concentrated tomato pulp made of fruits treated with methylthiophanate was redder than the others. The fungicide treatment increased or decreased the level of some chemical substances in the fruits in dependence on the applied fungicide, storage conditions and the length of storage, e.g. tomatoes treated with benomyl and stored for 14 days contained the highest level of vitamin C under 0% CO2:3%O2 and tomatoes treated with methylthiophanate contained the highest level of vitamin C under 38 mm Hg. Degradation of vitamin C in pulp was faster than in the concentrated pulp. Tomato pulp made of tomatoes treated with methylthiophanate contained the lowest level of vitamin C.

  11. Optimal Design of Modern Transformerless PV Inverter Topologies

    OpenAIRE

    Saridakis, Stefanos; Koutroulis, Eftichios; Blaabjerg, Frede

    2013-01-01

    The design optimization of H5, H6, neutral point clamped, active-neutral point clamped, and conergy-NPC transformerless photovoltaic (PV) inverters is presented in this paper. The components reliability in terms of the corresponding malfunctions, affecting the PV inverter maintenance cost during the operational lifetime period of the PV installation, is also considered in the optimization process. According to the results of the proposed design method, different optimal values of the PV inver...

  12. Fungi of genus Alternaria occurring on tomato

    Directory of Open Access Journals (Sweden)

    Joanna Marcinkowska

    2013-12-01

    Full Text Available Tomato early blight in central Poland was caused by Alternaria solani (A. porri f. sp., solani and A. alernata (A. tenuis. A. alternata was isolated more often than A. solani. All isolates of A. solani in controlled conditions killed tomato seedlings, while pathogenic isolates of A. alternata caused only slight seedling blight. In greenhouse tests A. solani proved to be strongly pathogenic for leaves and stems of tomato but A. alternata was weakly pathogenic. The latter species attacked only injured fruits while, A. solanicould penetrate through undamaged peel of fruits. Both of these species caused the same type of symptoms; the differences consisted only in intensification of disease symptoms. During 1974 and 1975 field tomatoes were moderately attacked by early blight. Thebest development of this disease occurred by the turn of August and September. Determinate variety 'New Yorker' was distinguished by more severe infection of stem parts of tomato whereas the fruits of a stock variety 'Apollo' were more strongly attacked.

  13. Pseudomonas syringae pv. phaseolicola isolated from weeds in bean crop fields.

    Science.gov (United States)

    Fernández-Sanz, A M; Rodicio, M R; González, A J

    2016-04-01

    Pseudomonas syringae pv. phaseolicola, the causative agent of halo blight in common bean (Phaseolus vulgaris L.), was isolated from weeds associated with bean crops in Spain. The bacterium was recovered from Fumaria sp, Mercurialis annua, Solanum nigrum and Sonchus oleraceus. Ps. s. pv. phaseolicola had previously been isolated from leguminous plants and S. nigrum, but to our knowledge, this is the first time it was recovered from the other three species. The isolates were phenotypically and genetically characterized, and they were compared with isolates recovered from common beans. Five different genotypic profiles were detected by PmeI-PFGE, two of them being of new description. Weed isolates were as pathogenic on bean plants as bean isolates, but they were not pathogenic on S. nigrum. Regarding the survival of the pathogen in weeds, Ps. s. pv. phaseolicola was isolated from So. oleraceus 11 weeks after the end of the bean crop. These results strongly support the idea of weeds as a potential source of inoculum for halo blight in bean. It has traditionally been considered that the main source of inoculum of Pseudomonas syringae pv. phaseolicola causing halo blight disease in Phaseolus vulgaris are the bean seeds, and that the host range of the bacterium is almost restricted to leguminous plants. In this study, the bacterium was recovered from four nonleguminous weed species collected in bean fields, and its permanence in weeds for at least 11 weeks after the harvesting of the beans was demonstrated. We have also proved that the strains isolated from weeds were pathogenic on bean plants. Accordingly, the host range of Ps. s. pv. phaseolicola could be broader than previously thought and weeds appear to be acting as a reservoir of the pathogen until the next crop. © 2016 The Society for Applied Microbiology.

  14. Solar cell junction temperature measurement of PV module

    KAUST Repository

    Huang, B.J.; Yang, P.E.; Lin, Y.P.; Lin, B.Y.; Chen, H.J.; Lai, R.C.; Cheng, J.S.

    2011-01-01

    The present study develops a simple non-destructive method to measure the solar cell junction temperature of PV module. The PV module was put in the environmental chamber with precise temperature control to keep the solar PV module as well

  15. Photovoltaic (PV) Pricing Trends: Historical, Recent, and Near-Term Projections

    Energy Technology Data Exchange (ETDEWEB)

    Feldman, David [National Renewable Energy Lab. (NREL), Golden, CO (United States); Barbose, Galen [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Margolis, Robert [National Renewable Energy Lab. (NREL), Golden, CO (United States); Wiser, Ryan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Darghouth, Naim [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Goodrich, Alan [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2012-11-30

    The installed capacity of global and U.S. photovoltaic (PV) systems has soared in recent years, driven by declining PV prices and government incentives. The U.S. Department of Energy’s (DOE) SunShot Initiative aims to make PV cost competitive without incentives by reducing the cost of PV-generated electricity by about 75% between 2010 and 2020. This summary report—based on research at Lawrence Berkeley National Laboratory (LBNL) and the National Renewable Energy Laboratory (NREL)—examines progress in PV price reductions to help DOE and other PV stakeholders manage the transition to a market-driven PV industry, and to provide clarity surrounding the wide variety of potentially conflicting data available about PV system prices.

  16. Tomato and tomato byproducts. Human health benefits of lycopene and its application to meat products: a review.

    Science.gov (United States)

    Viuda-Martos, M; Sanchez-Zapata, E; Sayas-Barberá, E; Sendra, E; Pérez-Álvarez, J A; Fernández-López, J

    2014-01-01

    During recent decades, the food industry, consumers, and regulatory authorities have developed a significant interest in functional foods because of their potential benefits for human health over and above their basic nutritional value. Tomato is the second most important vegetable crop in the world. The amount of the related wastes is estimated at up to 50,000 tons per year, representing a serious disposal problem with a consequent negative impact on the environment. Tomato byproducts contain a great variety of biologically active substances, principally lycopene, which have been demonstrated by in vitro and in vivo studies to possess antioxidant, hypolipidemic, and anticarcinogenic activities. The aim of this review is to present an overview of the functional and physiological properties of the principal bioactive compound present in tomato and tomato byproducts, lycopene, its addition to meat, and meat products.

  17. The Value of Transparency in Distributed Solar PV Markets

    Energy Technology Data Exchange (ETDEWEB)

    OShaughnessy, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Zamzam, Ahmed S [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-12-01

    Market transparency refers to the degree of customer awareness of product options and fair market prices for a given good. In The Value of Transparency in Distributed Solar PV Markets, we use residential solar photovoltaic (PV) quote data to study the value of transparency in distributed solar PV markets. We find that improved market transparency results in lower installation offer prices. Further, the results of this study suggest that PV customers benefit from gaining access to more PV quotes.

  18. Engineering resistance against Tomato yellow leaf curl virus via the CRISPR/Cas9 system in tomato

    KAUST Repository

    Mahfouz, Magdy M.

    2017-12-22

    CRISPR/Cas systems confer molecular immunity against phages and conjugative plasmids in prokaryotes. Recently, CRISPR/Cas9 systems have been used to confer interference against eukaryotic viruses. Here, we engineered Nicotiana benthamiana and tomato (Solanum lycopersicum) plants with the CRISPR/Cas9 system to confer immunity against the Tomato yellow leaf curl virus (TYLCV). Targeting the TYLCV genome with Cas9-single guide RNA at the sequences encoding the coat protein (CP) or replicase (Rep) resulted in efficient virus interference, as evidenced by low accumulation of the TYLCV DNA genome in the transgenic plants. The CRISPR/Cas9-based immunity remained active across multiple generations in the N. benthamiana and tomato plants. Together, our results confirmed the efficiency of the CRISPR/Cas9 system for stable engineering of TYLCV resistance in N. benthamiana and tomato, and opens the possibilities of engineering virus resistance against single and multiple infectious viruses in other crops.

  19. Structure and Origin of Xanthomonas arboricola pv. pruni Populations Causing Bacterial Spot of Stone Fruit Trees in Western Europe.

    Science.gov (United States)

    Boudon, Sylvain; Manceau, Charles; Nottéghem, Jean-Loup

    2005-09-01

    ABSTRACT Xanthomonas arboricola pv. pruni, the causal agent of bacterial spot on stone fruit, was found in 1995 in several orchards in southeastern France. We studied population genetics of this emerging pathogen in comparison with populations from the United States, where the disease was first described, and from Italy, where the disease has occurred since 1920. Four housekeeping genes (atpD, dnaK, efp, and glnA) and the intergenic transcribed spacer region were sequenced from a total of 3.9 kb of sequences, and fluorescent amplified fragment length polymorphism (FAFLP) analysis was performed. A collection of 64 X. arboricola pv. pruni strains, including 23 strains from France, was analyzed. The X. arboricola pv. pruni population had a low diversity because no sequence polymorphisms were observed. Population diversity revealed by FAFLP was lower for the West European population than for the American population. The same bacterial genotype was detected from five countries on three continents, a geographic distribution that can be explained by human-aided migration of bacteria. Our data support the hypothesis that the pathogen originated in the United States and subsequently has been disseminated to other stone-fruit-growing regions of the world. In France, emergence of this disease was due to a recent introduction of the most prevalent genotype of the bacterium found worldwide.

  20. Optimal design of PV and HP system

    DEFF Research Database (Denmark)

    Nepper-Rasmussen, Bjarke Christian; Rasmussen, Theis Bo

    2015-01-01

    Methods of utilizing residential produced photovoltaic (PV) power by converting to thermal energy through heat pumps (HP) are present in literature, where thermal energy is dispersed as either heat or hot water at the instant moment of PV production. In this paper an alternative solution is descr...... that the thermal storage with a BT is a better investment than a PV system without HP or no investment. Furthermore, it showed that the optimization model developed in this project is capable of finding the optimal combination of component sizes based on our data.......Methods of utilizing residential produced photovoltaic (PV) power by converting to thermal energy through heat pumps (HP) are present in literature, where thermal energy is dispersed as either heat or hot water at the instant moment of PV production. In this paper an alternative solution...... is described, where the thermal energy is stored in a buffer tank (BT) capable of dispersing heat to either the heating system of a house or a hot water tank, for later use. The thermal storage solution including a BT can increase the self-consumption of residentially produced PV power and thereby shift...

  1. Learning in PV trends and future prospects

    International Nuclear Information System (INIS)

    Schaeffer, G.J.; De Moor, H.H.C.

    2004-06-01

    For large scale application of PV cost reduction is essential. It is shown in this study that the price evolution is on track and even accelerating the last 15 years. Using an experience curve approach a learning rate of little over 20% was found consistent with other studies. As data were collected for small rooftop grid connected systems, it could be shown that this learning rate is not only found for modules, but also for BOS (all costs apart from the modules) in Germany as well as in the Netherlands. Projections of the future price of PV systems show that a learning rate of at least 20% is needed to make introduction of PV affordable. It is very effective to invest in learning, thus increasing the learning rate, as well as developing market segments were the value of PV is higher, such as residential PV systems in southern Europe

  2. Non-pathogenic Fusarium solani represses the biosynthesis of nematicidal compounds in vitro and reduces the biocontrol of Meloidogyne javanica by Pseudomonas fluorescens in tomato.

    Science.gov (United States)

    Siddiqui, I A; Shaukat, S S

    2003-01-01

    The aim of the present investigation was to determine the influence of various Fusarium solani strains on the production of nematicidal agent(s) in vitro and biocontrol of Meloidogyne javanica in tomato by Pseudomonas fluorescens strains CHA0 and CHA0/pME3424. Culture filtrates (CF) of P. fluorescens strain CHA0 and its diacetylphloroglucinol-overproducing derivative CHA0/pME3424 caused substantial mortality of M. javanica juveniles in vitro. Bacterial growth medium amended with the growth medium of F. solani repressed the nematicidal activity of the bacteria. Methanol extract of F. solani CF resulting from Czapek's Dox liquid (CDL) medium without zinc amendment repressed the nematicidal activity of the bacteria while the CF obtained from CDL medium amended with zinc did not. Conidial suspension of F. solani strain Fs5 (repressor strain for the biosynthesis of nematicidal compounds in P. fluorescens) reduced biocontrol potential of the bacterial inoculants against M. javanica in tomato while strain Fs3 (non-repressor) did not. Fusarium solani strains with increased nematicidal activity repress the biosynthesis of nematicidal compounds by P. fluorescens strains in vitro and greatly alter its biocontrol efficacy against root-knot nematode under natural conditions. Fusarium solani strains are distributed worldwide and found in almost all the agricultural fields which suggest that some mycotoxin-producing strains will also be found in almost any soil sample taken. Besides the suppressive effect of these metabolite-producing strains on the production of nematicidal compound(s) critical in biocontrol, F. solani strains may also affect the performance of mycotoxin-sensitive biocontrol bacteria effective against plant-parasitic nematodes.

  3. PV solar system feasibility study

    International Nuclear Information System (INIS)

    Ashhab, Moh’d Sami S.; Kaylani, Hazem; Abdallah, Abdallah

    2013-01-01

    Highlights: ► This research studies the feasibility of PV solar systems. ► The aim is to develop the theory and application of a hybrid system. ► Relevant research topics are reviewed and some of them are discussed in details. ► A prototype of the PV solar system is designed and built. - Abstract: This research studies the feasibility of PV solar systems and aims at developing the theory and application of a hybrid system that utilizes PV solar system and another supporting source of energy to provide affordable heating and air conditioning. Relevant research topics are reviewed and some of them are discussed in details. Solar heating and air conditioning research and technology exist in many developed countries. To date, the used solar energy has been proved to be inefficient. Solar energy is an abundant source of energy in Jordan and the Middle East; with increasing prices of oil this source is becoming more attractive alternative. A good candidate for the other system is absorption. The overall system is designed such that it utilizes solar energy as a main source. When the solar energy becomes insufficient, electricity or diesel source kicks in. A prototype of the PV solar system that operates an air conditioning unit is built and proper measurements are collected through a data logging system. The measured data are plotted and discussed, and conclusions regarding the system performance are extracted.

  4. Data monitoring system for PV solar generators

    International Nuclear Information System (INIS)

    Stoev, M.; Katerski, A.; Williams, A.

    2000-01-01

    The two 1.5 kWp photovoltaic (PV) solar generators are installed and the new PC data monitoring system is developed by applying EC standards for European Solar Test Installation (ESTI). The schematic system diagram of PV generator is presented. The recording parameters for analytical and global monitoring are discussed. The meteorological data from ESTI sensors, temperature sensor and electrical data from inverter and calibrated shunt are stored via analog digital converters (ADC) on a hard disk of data storage PC. Data Logger and Monitor software for automatic data acquisition, treatment and visual distance control of all output PV data from PV solar generator has been created

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

    Science.gov (United States)

    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 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.

  6. Simulation of Distributed PV Power Output in Oahu Hawaii

    Energy Technology Data Exchange (ETDEWEB)

    Lave, Matthew Samuel [Sandia National Lab. (SNL-CA), Livermore, CA (United States)

    2016-08-01

    Distributed solar photovoltaic (PV) power generation in Oahu has grown rapidly since 2008. For applications such as determining the value of energy storage, it is important to have PV power output timeseries. Since these timeseries of not typically measured, here we produce simulated distributed PV power output for Oahu. Simulated power output is based on (a) satellite-derived solar irradiance, (b) PV permit data by neighborhood, and (c) population data by census block. Permit and population data was used to model locations of distributed PV, and irradiance data was then used to simulate power output. PV power output simulations are presented by sub-neighborhood polygons, neighborhoods, and for the whole island of Oahu. Summary plots of annual PV energy and a sample week timeseries of power output are shown, and a the files containing the entire timeseries are described.

  7. Design optimization of transformerless grid-connected PV inverters including reliability

    DEFF Research Database (Denmark)

    Koutroulis, Eftichios; Blaabjerg, Frede

    2012-01-01

    Of the Electricity (LCOE) generated during the PV system lifetime period is minimized. The LCOE is calculated also considering the failure rates of the components, which affect the reliability performance and lifetime maintenance cost of the PV inverter. A design example is presented, demonstrating that compared...... to the non-optimized PV inverter structures, the PV inverters designed using the proposed optimization methodology exhibit lower total manufacturing and lifetime maintenance cost and inject more energy into the electric-grid and by that minimizing LCOE.......This paper presents a new methodology for optimal design of transformerless Photovoltaic (PV) inverters targeting a cost-effective deployment of grid-connected PV systems. The optimal values and types of the PV inverter components are calculated such that the PV inverter Levelized Cost...

  8. Design Optimization of Transformerless Grid-Connected PV Inverters Including Reliability

    DEFF Research Database (Denmark)

    Koutroulis, Eftichios; Blaabjerg, Frede

    2013-01-01

    such that the PV inverter LCOE generated during the PV system lifetime period is minimized. The LCOE is also calculated considering the failure rates of the components, which affect the reliability performance and lifetime maintenance cost of the PV inverter. A design example is presented, demonstrating...... that compared to the nonoptimized PV inverter structures, the PV inverters designed using the proposed optimization methodology exhibit lower total manufacturing and lifetime maintenance cost and inject more energy into the electric-grid and by that minimizing LCOE.......This paper presents a new methodology for optimal design of transformerless photovoltaic (PV) inverters targeting a cost-effective deployment of grid-connected PV systems. The optimal switching frequency as well as the optimal values and types of the PV inverter components is calculated...

  9. Impedance characterization of PV modules in outdoor conditions

    DEFF Research Database (Denmark)

    Oprea, Matei-lon; Thorsteinsson, Sune; Spataru, Sergiu

    2016-01-01

    Impedance spectroscopy (IS) has been used for laboratory characterizations of photovoltaic (PV) technologies under well controlled conditions. This work applies IS for outdoor characterization of PV panels, in order to observe the effect of irradiance (G) and temperature (T) on the PV module’s...

  10. Performance of a 34 kWp grid-connected PV system in Indonesia - A comparison of tropical and European PV systems

    NARCIS (Netherlands)

    Veldhuis, A.J.; Reinders, Angelina H.M.E.

    2014-01-01

    We analysed a monitored grid-connected PV system of 34 kWp in Indonesia to investigate the performance of PV systems in tropical climates. The PV system has been installed in Jayapura, the capital of the Province of Papua, Indonesia, by the beginning of 2012. Due to the aged gensets and frequent

  11. Pepino Mosaic Virus: a serious threat to tomato plants worldwide

    Directory of Open Access Journals (Sweden)

    Imane BIBI

    2017-09-01

    Full Text Available omato (Solanum lycopersicum is one of the widely grown crops worldwide. It is consumed in various forms and has excellent nutritional values. Presently, this crop is facing a serious threat to its yield and survival because of a potexvirus infection. One of the potexvirus species hampering tomato productions worldwide is Pepino mosaic virus (PepMV. This emerging virus is one of the most destructive plant diseases destroying tomato crops globally. It has spread to many countries worldwide including France, Italy, the UK, Poland, Belgium, the USA, Canada and China. PepMV genome consists of a positive-sense, single-stranded RNA molecule, approximately 6.4 kb in length. The genomic RNA contains five open reading frames (ORFs encoding for the coat protein (CP, the putative viral polymerase (RdRp and the triple gene block (TGB proteins. PepMV is efficiently transmitted mechanically. In other studies, seed transmission has been demonstrated. This article provides an overview of PepMV symptoms, transmission, different strains of PepMV, its genome organization and strategies employed for controlling it. The knowledge about the recent progress in the study of PepMV would help develop novel strategies for its control in agriculture.

  12. Influence of Heat Treatments on Carotenoid Content of Cherry Tomatoes

    OpenAIRE

    D'Evoli, Laura; Lombardi-Boccia, Ginevra; Lucarini, Massimo

    2013-01-01

    Tomatoes and tomato products are rich sources of carotenoids—principally lycopene, followed by β-carotene and lutein. The aim of this work was to study the effect of heat treatment on carotenoid content in cherry tomatoes. Raw and canned products were sampled and analysed; furthermore whole, skin and pulp fractions of cherry tomatoes were analysed when raw and home-processed, in order to better understand heat treatment effects. Lycopene content in canned tomatoes was two-fold higher than in ...

  13. Antioxidant and Antiplatelet Activities in Extracts from Green and Fully Ripe Tomato Fruits (Solanum lycopersicum and Pomace from Industrial Tomato Processing

    Directory of Open Access Journals (Sweden)

    Eduardo Fuentes

    2013-01-01

    Full Text Available The consumption of fruits and vegetables is accepted to be one of the strategies to reduce risk factors for these diseases. The aim of this study was to examine potential relationships between the antioxidant and the antiplatelet activities in green mature and fully ripe (red tomatoes and of lycopene-rich byproducts of tomato paste processing such as pomace. The total phenol content of tomato components was the highest in peels, pulp, and in the mucilaginous myxotesta covering the tomato seeds with values 36.9±0.8, 33.3±00.5, and 17.6±0.9 mg GAE/100 g, respectively (P<0.05. Tomato peels had the highest antioxidant activity, both, as measured by the FRAP (46.9±0.9 μmol Fe+2/g, P<0.05 and the DPPH assays (97.4±0.2%, 1000 μg/mL, P<0.05. Pomace extracts showed the highest antiplatelet activity induced by ADP, collagen, TRAP-6, and arachidonic acid. While the maturation stage of the tomato fruit affected the antioxidant effect, antiplatelet activity was independent of fruit ripeness. Finally, based on the present results, tomato and its byproducts may be considered as a valuable source of antioxidant and antiplatelet activities.

  14. Pseudomonas floridensis sp. nov., a bacterial pathogen isolated from tomato.

    Science.gov (United States)

    Timilsina, Sujan; Minsavage, Gerald V; Preston, James; Newberry, Eric A; Paret, Matthews L; Goss, Erica M; Jones, Jeffrey B; Vallad, Gary E

    2018-01-01

    An unusual fluorescent pseudomonad was isolated from tomato exhibiting leaf spot symptoms similar to bacterial speck. Strains were fluorescent, oxidase- and arginine-dihydrolase-negative, elicited a hypersensitive reaction on tobacco and produced a soft rot on potato slices. However, the strains produced an unusual yellow, mucoid growth on media containing 5 % sucrose that is not typical of levan. Based on multilocus sequence analysis using 16S rRNA, gap1, gltA, gyrB and rpoD, these strains formed a distinct phylogenetic group in the genus Pseudomonas and were most closely related to Pseudomonas viridiflava within the Pseudomonassyringae complex. Whole-genome comparisons, using average nucleotide identity based on blast, of representative strain GEV388 T and publicly available genomes representing the genus Pseudomonas revealed phylogroup 7 P. viridiflava strain UASW0038 and P. viridiflava type strain ICMP 2848 T as the closest relatives with 86.59 and 86.56 % nucleotide identity, respectively. In silico DNA-DNA hybridization using the genome-to-genome distance calculation method estimated 31.1 % DNA relatedness between GEV388 T and P. viridiflava ATCC 13223 T , strongly suggesting the strains are representatives of different species. These results together with Biolog GEN III tests, fatty acid methyl ester profiles and phylogenetic analysis using 16S rRNA and multiple housekeeping gene sequences demonstrated that this group represents a novel species member of the genus Pseudomonas. The name Pseudomonas floridensis sp. nov. is proposed with GEV388 T (=LMG 30013 T =ATCC TSD-90 T ) as the type strain.

  15. Endophytic Bacteria Suppress Bacterial Wilt of Tomato Caused by Ralstonia solanacearum and Activate Defense-related Metabolites

    Directory of Open Access Journals (Sweden)

    Fahime Safdarpour

    2017-12-01

    Full Text Available Introduction: Phytopathogenic microorganisms affect plant health and burden a major threat to food production and ecosystem stability. Increasing the use of chemical pesticides for plant diseases control causes several negative effects on human and environment health. Furthermore, increasing public awareness about the side effects of them led to a research to find alternatives for these products. One of the alternative methods is bio-control utilizing plant associated antagonistic microorganisms. Materials and methods: In this study, 80 endophytic bacteria were isolated from tomato tissues. Their antagonistic activity screened based on agar diffusion test, against tomato bacterial wilt disease (Ralstonia solanacearum. They were identified based on the morphological, biochemical properties and 16s rRNA sequence analyses. These strains were evaluated in greenhouse and tested for their ability to induce the production of defense-related enzymes in plants e.g. Peroxidase (PO, polyphenoloxidase (PPO and phenolics based on spectrophotometer method. Results: Results showed FS67, FS167 and FS184 strains had maximum inhibition zone forming. They identified as Pseudomonas mossellii, P. fuorescence and P. brassicacearum respectively. FS67 and FS167 strains significantly reduced disease in greenhouse. There was a significant increase in the activity of PO, PPO and phenolics in tomato plants treated with FS67, FS167 and pathogen. Discussion and conclusion: The present study has shown that P. mosselli and P. fuorescence might have the potential to control R. solanacearum. However, the good results obtained in vitro cannot be gained the same as those in greenhouse or field conditions. So, further experiments are needed to determine the effectiveness of these isolates under field conditions.This work support the view that increased defense enzymes activities could be involved, at least in part, in the beneficial effects of endophytic bacteria on plants growth

  16. Study of bypass diodes configuration on PV modules

    Energy Technology Data Exchange (ETDEWEB)

    Silvestre, S.; Boronat, A.; Chouder, A. [Electronics Engineering Department - UPC., C/Jordi Girona 1-3, Modul C4 Campus Nord UPC., 08034 Barcelona (Spain)

    2009-09-15

    A procedure of simulation and modelling solar cells and PV modules, working partially shadowed in Pspice environment, is presented. Simulation results have been contrasted with real measured data from a commercial PV module of 209 Wp from Siliken. Some cases of study are presented as application examples of this simulation methodology, showing its potential on the design of bypass diodes configuration to include in a PV module and also on the study of PV generators working in partial shading conditions. (author)

  17. Is tomato a healthy and/or functional food?

    Directory of Open Access Journals (Sweden)

    Inmaculada Navarro-González

    2016-12-01

    Full Text Available This paper is a literature review about the presence of bioactive compounds in tomato and tomato based food, and these compounds function to promote health in the human organism. Several scientific studies show that tomato and tomato based products have several molecules, some of them with antioxidant activity, that protect lipids, lipoproteins, DNA, etc. against free radicals. This function could be one of the causes of the apparent link between consumption and protection of degenerative and chronic diseases such as cancer, cardiovascular disease, Parkinson’s disease, etc. More recent studies have proposed different biochemical mechanisms in which tomato components can exert this beneficial role on health. In addition, several studies seem to show that the greatest benefit of this food is due to the synergistic effect between all its compounds. Some epidemiological studies associate that regular intake has several beneficial effects on health. Due to the association between bioactive compounds, daily tomato consumption and its effect on human health, the aim of the current literature review is summarize the compounds in this food and its possible actions on health.

  18. Using hyperspectral imaging technology to identify diseased tomato leaves

    Science.gov (United States)

    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.

  19. Latin America as new PV market opportunity

    International Nuclear Information System (INIS)

    Weiss, Ingrid

    2015-01-01

    It is important to recognize solar energy as an international and strategic opportunity for the European market to expand. The objective of this paper is to apply the methodology created during the PV Parity project for analyzing PV Competitiveness in the emerging residential PV market in Brazil, using information from the State of Rio de Janeiro. The dynamic competitiveness analysis was performed considering the price with and without taxes in order to assess the year when PV will reach grid parity in Rio de Janeiro and how the taxes impact on the results. Results are divided into 3 scenarios: Optimistic, Conservative, and Conservative Moderate. The LCOE of residential systems will likely become competitive with the residential electricity tariffs between 2020 and 2030, assuming the residential tariffs in Rio de Janeiro. This is an indicator that PV energy business opportunities are increasing in Brazil and, with the adequate policy support, its market competitiveness could be improved. We are also looking in other markets of Latin America. (full text)

  20. Dissipation of heat from building integrated PV

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, C.M.L.

    2001-07-01

    The objectives of the project were to investigate methods for improving heat transfer and the reflection of heat from PV modules in building integrated situations and to develop the design of a building integrated PV element with improved heat transfer characteristics, with the aim of reducing the operating temperature of the PV cells. The prototypes developed for improving heat transfer have only shown small reductions in the PV cell operating temperature and these results have not been fully quantified due to problems associated with experimental testing. The improvement in the overall electrical performance of PV modules operating at lower temperatures is consequently even smaller. As a result, none of the prototypes can be considered to be economically viable. Based upon the theoretical and experimental results of this work, it is the recommendation of this project that no further work be conducted in improving BIPV performance through improved heat transfer of BIPV. (Author)

  1. A role in immunity for Arabidopsis cysteine protease RD21, the ortholog of the tomato immune protease C14.

    Directory of Open Access Journals (Sweden)

    Takayuki Shindo

    Full Text Available Secreted papain-like Cys proteases are important players in plant immunity. We previously reported that the C14 protease of tomato is targeted by cystatin-like EPIC proteins that are secreted by the oomycete pathogen Phytophthora infestans (Pinf during infection. C14 has been under diversifying selection in wild potato species coevolving with Pinf and reduced C14 levels result in enhanced susceptibility for Pinf. Here, we investigated the role C14-EPIC-like interactions in the natural pathosystem of Arabidopsis with the oomycete pathogen Hyaloperonospora arabidopsidis (Hpa. In contrast to the Pinf-solanaceae pathosystem, the C14 orthologous protease of Arabidopsis, RD21, does not evolve under diversifying selection in Arabidopsis, and rd21 null mutants do not show phenotypes upon compatible and incompatible Hpa interactions, despite the evident lack of a major leaf protease. Hpa isolates express highly conserved EPIC-like proteins during infections, but it is unknown if these HpaEPICs can inhibit RD21 and one of these HpaEPICs even lacks the canonical cystatin motifs. The rd21 mutants are unaffected in compatible and incompatible interactions with Pseudomonas syringae pv. tomato, but are significantly more susceptible for the necrotrophic fungal pathogen Botrytis cinerea, demonstrating that RD21 provides immunity to a necrotrophic pathogen.

  2. Influence of agitation and aeration in xanthan production by Xanthomonas campestris pv pruni strain 101 Influencia de la agitación y la aireación en la producción de xantano por Xanthomonas campestris pv. pruni cepa 101

    Directory of Open Access Journals (Sweden)

    C. D. Borges

    2008-06-01

    Full Text Available Production, viscosity, and chemical composition of xanthan synthesized by bacterium Xanthomonas campestris pv pruni strain 101 were evaluated in bioreactor systems. During the process, the volumetric oxygen mass transfer coefficient (kLa and the biomass were determined and the pH was monitored. The cultures were grown in a 3 l bioreactor, with aeration and agitation varying as follows: conditions (A 300 rpm, 3 vvm and (B 200 rpm, 2 vvm, at 28 °C. Our results showed that gum production was dependent on kLa, with a maximum yield of 8.15 g/l at 300 rpm, 3 vvm, 54 h of fermentation, kLa 21.4/h, while biomass was not affected. All aqueous solutions of 3% (w/v xanthans synthesized showed a pseudoplastic behavior. The highest viscosity was reached under the strongest aeration/agitation conditions. All xanthan samples contained glucose, mannose, rhamnose, and glucuronic acid as their main components. The highest agitation and aeration rates used under condition A (300 rpm and 3 vvm favorably influenced the yield and viscosity of the xanthan produced by bacterium X. campestris pv pruni 101 at different fermentation times.Se evaluó la producción, viscosidad y composición química del xantano sintetizado por la bacteria Xanthomonas campestris pv. pruni cepa 101 en un fermentador. Durante el proceso se controló el pH y se determinaron el coeficiente de transferencia de masa de oxígeno (kLa y la producción de masa celular seca. Los cultivos se realizaron en un fermentador de 3 l variando la aireación y la agitación, en las siguientes condiciones: (A 300 rpm, 3 vvm y (B 200 rpm, 2 vvm; a 28 °C. Nuestros resultados mostraron que la producción de goma fue dependiente del kLa, con un rendimiento máximo de 8,15 g/l a 300 rpm y 3 vvm a las 54 h de fermentación, kLa de 21,4/h, mientras que la producción de biomasa no se afectó. Todas las soluciones acuosas de xantano al 3% (m/v sintetizadas presentaron comportamiento pseudoplástico. La mayor

  3. The potential of solar PV in Ontario

    International Nuclear Information System (INIS)

    McMonagle, R.

    2005-01-01

    Canada has lagged behind other industrialized nations in the growth of solar energy markets. Currently, over 78 per cent of the global market for solar energy is for grid-connected applications where power is fed into the electrical distribution network. Less than 3.5 per cent of the Canadian solar market is grid-connected. This report investigated the potential size of the photovoltaic (PV) market in Ontario given adequate support from both governments and utilities. The forecast was based on sustainable growth levels that the solar industry as a whole might maintain over an extended period of time. It was suggested that it is technically feasible to install over 3000 MW of PV in single, detached homes in the province, which could generate over 3200 GWh each year. If the right policy conditions were put in place, the technical potential for PV on all buildings in Ontario is over 14,000 MW by 2025, which would generate over 13,000 GWh annually. Support mechanisms such as the Advanced Renewable Tariff (ART) or Standard Offer Contracts (SOC) will enable the PV industry to build capacity. Future markets for PV include new homes, commercial buildings and the existing housing stock. With a properly designed system, it is forecasted that the deployment of PV by 2025 could result in the involvement of 400,000 homes with over 1200 MW of installed capacity and over 290 MW installed annually by 2025. Recommendations to Ontario Power Authority's (OPA) report supply mix report focused on the use of SOCs as the appropriate support mechanism to start building solar capacity in Ontario, as projections using SOCs would see Ontario following the growth patterns of other nations. It was concluded that the OPA report does not acknowledge the current growth rates of PV globally, nor does it fully consider the potential of PV in Ontario. 9 refs., 8 figs

  4. Influence of Heat Treatments on Carotenoid Content of Cherry Tomatoes

    Directory of Open Access Journals (Sweden)

    Laura D'Evoli

    2013-07-01

    Full Text Available Tomatoes and tomato products are rich sources of carotenoids—principally lycopene, followed by β-carotene and lutein. The aim of this work was to study the effect of heat treatment on carotenoid content in cherry tomatoes. Raw and canned products were sampled and analysed; furthermore whole, skin and pulp fractions of cherry tomatoes were analysed when raw and home-processed, in order to better understand heat treatment effects. Lycopene content in canned tomatoes was two-fold higher than in raw tomatoes (11.60 mg/100 g versus 5.12 mg/100 g. Lutein and β-carotene were respectively 0.15 mg/100 g and 0.75 mg/100 g in canned tomatoes versus 0.11 mg/100 g and 1.00 mg/100 g in raw tomatoes. For home-processed tomatoes, β-carotene and lutein showed a content decrease in all thermally treated products. This decrease was more evident for β-carotene in the skin fraction (−17%, while for lutein it was greater in the pulp fraction (−25%. Lycopene presented a different pattern: after heat treatment its concentration increased both in the whole and in pulp fractions, while in the skin fraction it decreased dramatically (−36%. The analysis of the isomers formed during the thermal treatment suggests that lycopene is rather stable inside the tomato matrix.

  5. Influence of Heat Treatments on Carotenoid Content of Cherry Tomatoes.

    Science.gov (United States)

    D'Evoli, Laura; Lombardi-Boccia, Ginevra; Lucarini, Massimo

    2013-07-31

    Tomatoes and tomato products are rich sources of carotenoids-principally lycopene, followed by β-carotene and lutein. The aim of this work was to study the effect of heat treatment on carotenoid content in cherry tomatoes. Raw and canned products were sampled and analysed; furthermore whole, skin and pulp fractions of cherry tomatoes were analysed when raw and home-processed, in order to better understand heat treatment effects. Lycopene content in canned tomatoes was two-fold higher than in raw tomatoes (11.60 mg/100 g versus 5.12 mg/100 g). Lutein and β-carotene were respectively 0.15 mg/100 g and 0.75 mg/100 g in canned tomatoes versus 0.11 mg/100 g and 1.00 mg/100 g in raw tomatoes. For home-processed tomatoes, β-carotene and lutein showed a content decrease in all thermally treated products. This decrease was more evident for β-carotene in the skin fraction (-17%), while for lutein it was greater in the pulp fraction (-25%). Lycopene presented a different pattern: after heat treatment its concentration increased both in the whole and in pulp fractions, while in the skin fraction it decreased dramatically (-36%). The analysis of the isomers formed during the thermal treatment suggests that lycopene is rather stable inside the tomato matrix.

  6. The Biocontrol Efficacy of Streptomyces pratensis LMM15 on Botrytis cinerea in Tomato

    OpenAIRE

    Qinggui Lian; Jing Zhang; Liang Gan; Qing Ma; Zhaofeng Zong; Yang Wang

    2017-01-01

    LMM15, an actinomycete with broad spectrum antifungal activity, was isolated from a diseased tomato leaf using the baiting technique. A phylogenetic tree analysis based on similarity percentage of 16S rDNA sequences showed that the bacterium was 97.0% affiliated with the species Streptomyces pratensis. This strain was therefore coded as S. pratensis LMM15. The ferment filtrate of LMM15 had ability to inhibit mycelia growth of Botrytis cinerea and reduce lesion expansion of gray mold on detach...

  7. Hexanoic acid is a resistance inducer that protects tomato plants against Pseudomonas syringae by priming the jasmonic acid and salicylic acid pathways.

    Science.gov (United States)

    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.

  8. A detailed thermal-electrical model of three photovoltaic/thermal (PV/T) hybrid air collectors and photovoltaic (PV) module: Comparative study under Algiers climatic conditions

    International Nuclear Information System (INIS)

    Slimani, Mohamed El Amine; Amirat, Madjid; Kurucz, Ildikó; Bahria, Sofiane; Hamidat, Abderrahmane; Chaouch, Wafa Braham

    2017-01-01

    Highlights: • A detailed thermal and electrical model for PV and PV/T systems has been presented. • The developed numerical model was validated successfully with previously published experimental results. • A comparative study between four solar devices (PV and PV/T systems) was carried out. • The experimental weather conditions of Algiers site are used in the numerical model. • The glazed double-pass photovoltaic/thermal air collector shows the best overall energy efficiency. - Abstract: The thermal photovoltaic hybrid collector is a genuine cogeneration technology; it can produce electricity and heat simultaneously. In this paper, a comparative study is presented between four solar device configurations: photovoltaic module (PV-I), conventional hybrid solar air collector (PV/T-II), glazed hybrid solar air collector (PV/T-III) and glazed double-pass hybrid solar air collector (PV/T-IV). A numerical model is developed and validated through experimental results indicated in the previous literature. The numerical model takes the heat balance equations and different thermal and electrical parameters into account for each configuration included in this study, the energy performances are evaluated with a sample weather data of Algiers site. The numerical results show that the daily average of overall energy efficiency reaches: 29.63%, 51.02%, 69.47% and 74% for the first (PV-I), the second (PV/T-II), the third (PV/T-III) and the fourth (PV/T-IV) configurations respectively. These values are obtained with an air flow of 0.023 kg/s and introducing a sample of experimental weather data collected in Algiers site for a sunny day in summer.

  9. Reproductive performance of seven strains of the tomato red spider mite Tetranychus evansi (Acari: Tetranychidae) at five temperatures

    DEFF Research Database (Denmark)

    Gotoh, T.; Sugimoto, N.; Pallini, A.

    2010-01-01

    The tomato red spider mite Tetranychus evansi Baker et Pritchard occurs on solanaceous plants, and causes serious damage to a variety of crops in Africa and Europe. In 2001 this species was also found in Japan, on nightshade (Solanum nigrum L.), and its invasion to solanaceous of agricultural imp...

  10. Impact of residential PV adoption on Retail Electricity Rates

    International Nuclear Information System (INIS)

    Cai, Desmond W.H.; Adlakha, Sachin; Low, Steven H.; De Martini, Paul; Mani Chandy, K.

    2013-01-01

    The price of electricity supplied from home rooftop photo voltaic (PV) solar cells has fallen below the retail price of grid electricity in some areas. A number of residential households have an economic incentive to install rooftop PV systems and reduce their purchases of electricity from the grid. A significant portion of the costs incurred by utility companies are fixed costs which must be recovered even as consumption falls. Electricity rates must increase in order for utility companies to recover fixed costs from shrinking sales bases. Increasing rates will, in turn, result in even more economic incentives for customers to adopt rooftop PV. In this paper, we model this feedback between PV adoption and electricity rates and study its impact on future PV penetration and net-metering costs. We find that the most important parameter that determines whether this feedback has an effect is the fraction of customers who adopt PV in any year based solely on the money saved by doing so in that year, independent of the uncertainties of future years. These uncertainties include possible changes in rate structures such as the introduction of connection charges, the possibility of PV prices dropping significantly in the future, possible changes in tax incentives, and confidence in the reliability and maintainability of PV. -- Highlights: •Households who install PV reduce their electricity consumption from the grid. •Electricity rates must increase for utility companies to recover its fixed costs. •However, higher electricity rates give households more incentives to adopt PV. •We find that this feedback has significant impact on PV uptake only in later years. •Utility companies could lose a significant fraction of high consumption customers

  11. Remote and Centralized Monitoring of PV Power Plants

    DEFF Research Database (Denmark)

    Kopacz, Csaba; Spataru, Sergiu; Sera, Dezso

    2014-01-01

    the inverters within each PV plant. The monitoring software stores the PV measurements in a data warehouse optimized for managing and data mining large amounts of data, from where it can be later visualized, analyzed and exported. By combining PV production measurements data with I-V curve measurements...

  12. SunShot 2030 for Photovoltaics (PV): Envisioning a Low-cost PV Future

    Energy Technology Data Exchange (ETDEWEB)

    Cole, Wesley J. [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Frew, Bethany A. [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Gagnon, Pieter J. [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Richards, James [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Sun, Yinong [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Margolis, Robert M. [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Woodhouse, Michael A. [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-09-12

    In this report we summarize the implications, impacts, and deployment potential of reaching the SunShot 2030 targets for the electricity system in the contiguous United States. We model 25 scenarios of the U.S. power sector using the Regional Energy Deployment Systems (ReEDS) and Distributed Generation (dGen) capacity expansion models. The scenarios cover a wide range of sensitivities to capture future uncertainties relating to fuel prices, retirements, renewable energy capital costs, and load growth. We give special attention to the potential for storage costs to also rapidly decline due to its large synergies with low-cost solar. The ReEDS and dGen models project utility- and distributed-scale power sector evolution, respectively, for the United States. Both models have been designed with special emphasis on capturing the unique traits of renewable energy, including variability and grid integration requirements. Across the suite of scenarios modeled, we find that reaching the SunShot 2030 target has the potential to lead to significant capacity additions of PV in the United States. By 2050, PV penetration levels are projected to reach 28-46 percent of total generation. If storage also sees significant reductions in cost, then the 2050 solar penetration levels could reach 41-64 percent. PV deployment is projected to occur in all of the lower 48 states, though the specific deployment level is scenario dependent. The growth in PV is projected to be dominated by utility-scale systems, but the actual mix between utility and distributed systems could ultimately vary depending on how policies, system costs, and rate structures evolve.

  13. Prediction of processing tomato peeling outcomes

    Science.gov (United States)

    Peeling outcomes of processing tomatoes were predicted using multivariate analysis of Magnetic Resonance (MR) images. Tomatoes were obtained from a whole-peel production line. Each fruit was imaged using a 7 Tesla MR system, and a multivariate data set was created from 28 different images. After ...

  14. Extracytoplasmic function sigma factors in Pseudomonas syringae

    DEFF Research Database (Denmark)

    Kiil, Kristoffer; Oguiza, J.A.; Ussery, D.W.

    2005-01-01

    Genome analyses of the plant pathogens Pseudomonas syringae pv. tomato DC3000, pv. syringae B728a and pv. phaseolicola 1448A reveal fewer extracytoplasmic function (ECF) sigma factors than in related Pseudomonads with different lifestyles. We highlight the presence of a P. syringae-specific ECF...

  15. Screening of tomato varieties for fruit tree based Agroforestry system

    Directory of Open Access Journals (Sweden)

    J. Hossain

    2014-12-01

    Full Text Available An experiment was conducted with four tomato varieties under a six year old orchard was accomplished at the Bangabandhu Sheikh Mujibur Rahman Agricultural University (BSMRAU research farm during October 2011 to April 2012. The experiment was laid out in a Randomized Complete Block Design with three replications. Four tomato varieties (BARI Tomato 2, BARI Tomato 8, BARI Tomato 14 and BARI Tomato 15 were grown under guava, mango, olive and control. Results showed that light availability in control plot (999.75 μ mol m-2s-1 was remarkably higher over fruit tree based agroforestry systems and it was 58.8, 43.9 and 31.5% of the control for guava, mango and olive based systems, respectively. The shortest tomato plant was observed in olive based system (54.91 cm, while the tallest plant was observed in mango based system (60.09 cm. The highest SPAD value and number of primary branches per plant was recorded in control plot. Fruit length, fruit girth was found lowest in olive based system. The highest yield (34.06 t ha-1 was recorded in control plot while the lowest yield (10.26 t ha-1 was recorded in olive based system. The economic performance of fruit tree based tomato production system showed that both the net return and BCR of mango and guava based system was higher over control and olive based system. The contents of organic carbon, nitrogen, available phosphorus, potassium and sulfur of before experimentation soil were slightly higher in fruit tree based agroforestry systems than the control. After experimentation, nutrient elements in soil were found increased slightly than initial soils. Fruit tree based agroforestry systems could be ranked based on the economic performance as mango> guava> control> olive based system with BARI Tomato 15, BARI Tomato 2, BARI Tomato 14 and BARI Tomato 8, respectively.

  16. The Value of Transparency in Distributed Solar PV Markets

    Energy Technology Data Exchange (ETDEWEB)

    OShaughnessy, Eric J. [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Margolis, Robert M. [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-10-09

    Distributed solar photovoltaic (PV) markets are relatively non-transparent: PV price and product information is not readily available, searching for this information is costly (in terms of time and effort), and customers are mostly unfamiliar with the new technology. Quote aggregation, where third-party companies collect PV quotes on behalf of customers, may be one way to increase PV market transparency. In this paper, quote aggregation data are analyzed to study the value of transparency for distributed solar PV markets. The results suggest that easier access to more quotes results in lower prices. We find that installers tend to offer lower prices in more competitive market environments. We supplement the empirical analysis with key findings from interviews of residential PV installers.

  17. Low concentrator PV optics optimization

    Science.gov (United States)

    Sharp, Leonard; Chang, Ben

    2008-08-01

    Purpose: Cost reduction is a major focus of the solar industry. Thin film technologies and concentration systems are viable ways to reducing cost, with unique strengths and weakness for both. Most of the concentrating PV work focuses on high concentration systems for reducing energy cost. Meanwhile, many believe that low concentrators provide significant cost reduction potential while addressing the mainstream PV market with a product that acts as a flat panel replacement. This paper analyzes the relative benefit of asymmetric vs. symmetric optics for low-concentrators in light of specific PV applications. Approach: Symmetric and asymmetric concentrating PV module performance is evaluated using computer simulation to determine potential value across various geographic locations and applications. The selected optic design is modeled against standard cSi flat panels and thin film to determine application fit, system level energy density and economic value. Results: While symmetric designs may seem ideal, asymmetric designs have an advantage in energy density. Both designs are assessed for aperture, optimum concentration ratio, and ideal system array configuration. Analysis of performance across climate specific effects (diffuse, direct and circumsolar) and location specific effects (sunpath) are also presented. The energy density and energy production of low concentrators provide a compelling value proposition. More significantly, the choice of optics for a low concentrating design can affect real world performance. With the goal of maximizing energy density and return on investment, this paper presents the advantages of asymmetric optic concentration and illustrates the value of this design within specific PV applications.

  18. Control of the Tomato Leafminer, Tuta absoluta (Lepidoptera: Gelechiidae), in Open-Field Tomatoes by Indigenous Natural Enemies Occurring in Israel.

    Science.gov (United States)

    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.

  19. Commercialization and business development of grid-connected PV at SMUD

    International Nuclear Information System (INIS)

    Osborn, D.E.

    1998-01-01

    SMUD has completed its first 5 year, 6 MW PV commercialization effort based on the sustained, orderly development of the utility PV market. SMUD has begun a 5 year, 10 MW program designed to complete a process that will result in PV being at a market competitive price by 2002 and as a sustainable business opportunity for SMUD. As part of this effort, by the end of 1997, SMUD had installed over 450 PV systems totaling 6 MW. These included over 420 residential rooftop systems as well as commercial buildings, parking lots and substation systems. Under its new Business Plan, SMUD has signed contracts for an additional 10 MW of PV systems for 1998 through 2002 with cost decreasing to less than $3/W. As part of its new competitive business strategy responding to changes the utility industry is undergoing, SMUD has incorporated PV as a key business opportunity. SMUD has established partnerships with its customers through the PV Pioneer green pricing program, with DOE and UPVG through TEAM-UP and Million Solar Roofs to advance PV commercialization and to develop rooftops as PV power plant sites and with other utilities through its PV Partnership program

  20. Evaluation of some varieties and breeding lines of tomato (Lycopersison sp) against tomato yellow leaf curl disease in the Greater Accra Region (Ghana)

    International Nuclear Information System (INIS)

    Kusi-Adjei, R.

    2011-01-01

    A series of experiments were conducted to evaluate ten (10) tomato varieties and breeding lines against tomato yellow leaf curl virus disease in Ghana. The research was undertaken at the research farm of the Biotechnology and Nuclear Agriculture Research Institute of the Ghana Atomic Energy Commission. Ten tomato varieties and breeding lines were evaluated in the field under natural whitefly inoculation in insect-proof cages. The field trial was done in the dry season from October, 2010 to February, 2011 and wet season from March, 2011 to July, 2011. Plants in the fields and in the cage exhibited varied symptoms such as leaf curling, leaf yellowing and reduced leaf sizes. Assessment of disease incidence and symptom severity using a four point scale (0-4) showed that, in the field there was higher disease incidence in the dry season as compared to the wet season. This was attributed to the higher number of whiteflies in the dry season as demonstrated through a whitefly population survey conducted in the field. Differences among means for disease incidence and whitefly surveys on the ten tomato varieties and breeding lines were statistically significant (p≤ 0.05). Wild Tomato (Solanum pimpinellifollium) and two hybrids, Wosowoso x Wild Tomato and Cherry Red x Wild Tomato exhibited signs of resistance in the field and did not show any symptoms of TYLCV disease symptoms. All the commercial varieties were highly susceptible and showed severe symptoms. Evaluation of fruit yield in the field revealed that the commercial variety Tomato Advanta had the heaviest fruit weight (42 g/ fruit) whilst Wosowoso had the highest total fruit yield (5.74 t/ha) in the wet season. Wild Tomato and the hybrids produced higher number of fruits compared to the commercial varieties. There were highly significant differences in the means of number of fruits, fruit weight (g) and total fruit yield (t/ha) among the ten tomato varieties and breeding lines in both the wet and dry seasons

  1. Tomato yellow leaf curl virus can be acquired and transmitted by Bemisia tabaci (Gennadius) from tomato fruits

    NARCIS (Netherlands)

    Delatte, H.; Dalmon, A.; Rist, D.; Soustrade, I.; Wuster, G.; Lett, J.M.; Goldbach, R.W.; Peterschmitt, M.; Reynaud, B.

    2003-01-01

    The whitefly Bemisia tabaci is an insect pest causing worldwide economic losses, especially as a vector of geminiviruses such as Tomato yellow leaf curl virus (TYLCV). Currently, imported and exported tomato fruit are not monitored for TYLCV infection because they are not considered to represent a

  2. Synthesis of Ultra-Small Platinum, Palladium and Gold Nanoparticles by Shewanella loihica PV-4 Electrochemically Active Biofilm and Their Enhanced Catalytic Activities

    KAUST Repository

    Ahmed, Elaf; Kalathil, Shafeer; Shi, Le; Alharbi, Ohoud; Li, Renyuan; Zaouri, Noor A.; Wang, Peng

    2018-01-01

    strain of Shewanella loihica PV-4 and successfully synthesized USNPs of noble metal Au, Pd, and Pt. The synthesized USNPs had a size range between 2 and 7 nm and exhibited excellent catalytic performance in dye decomposition. The results of this work

  3. TRNSYS HYBRID wind diesel PV simulator

    Energy Technology Data Exchange (ETDEWEB)

    Quinlan, P.J.A.; Mitchell, J.W.; Klein, S.A.; Beckman, W.A.; Blair, N.J. [Univ. of Wisconsin, Madison, WI (United States)

    1996-12-31

    The Solar Energy Laboratory (SEL) has developed a wind diesel PV hybrid systems simulator, UW-HYBRID 1.0, an application of the TRNSYS 14.2 time-series simulation environment. An AC/DC bus links up to five diesels and wind turbine models, along with PV modules, a battery bank, and an AC/DC converter. Multiple units can be selected. PV system simulations include solar angle and peak power tracking options. Weather data are Typical Meteorological Year data, parametrically generated synthesized data, or external data files. PV performance simulations rely on long-standing SEL-developed algorithms. Loads data are read as scalable time series. Diesel simulations include estimated fuel-use and waste heat output, and are dispatched using a least-cost of fuel strategy. Wind system simulations include varying air density, wind shear and wake effects. Time step duration is user-selectable. UW-HYBRID 1.0 runs in Windows{reg_sign}, with TRNSED providing a customizable user interface. 12 refs., 6 figs.

  4. Environmental and exergy benefit of nanofluid-based hybrid PV/T systems

    International Nuclear Information System (INIS)

    Hassani, Samir; Saidur, R.; Mekhilef, Saad; Taylor, Robert A.

    2016-01-01

    Highlights: • Environmental and ExPBT analysis of different PV/T configurations is presented. • The exergy payback time of nanofluid-based hybrid PV/T system is about 2 years. • Nanofluid-based hybrid PV/T system is a reliable solution for pollution prevention. • Nanofluid-based hybrid PV/T system is highly recommended at high solar concentration. - Abstract: Photovoltaic/thermal (PV/T) solar systems, which produce both electrical and thermal energy simultaneously, represent a method to achieve very high conversion rates of sunlight into useful energy. In recent years, nanofluids have been proposed as efficient coolants and optical filter for PV/T systems. Aim of this paper is to theoretically analyze the life cycle exergy of three different configurations of nanofluids-based PV/T hybrid systems, and compare their performance to a standard PV and PV/T system. Electrical and thermal performance of the analyzed solar collectors was investigated numerically. The life cycle exergy analysis revealed that the nanofluids-based PV/T system showed the best performance compared to a standard PV and PV/T systems. At the optimum value of solar concentration C, nanofluid-based PV/T configuration with optimized optical and thermal properties produces ∼1.3 MW h/m 2 of high-grade exergy annually with the lowest exergy payback time of 2 years, whereas these are ∼0.36, ∼0.79 MW h/m 2 and 3.48, 2.55 years for standard PV and PV/T systems, respectively. In addition, the nanofluids-based PV/T system can prevent the emissions of about 448 kg CO 2 eq m −2 yr −1 . Overall, it was found that the nanofluids-based PV/T with optimized optical and thermal properties has potential for further development in a high-concentration solar system.

  5. Less CO2 by means of photovoltaic energy (PV)

    International Nuclear Information System (INIS)

    Alsema, E.A.; Van Brummelen, M.

    1992-11-01

    Regarding the title subject special attention is paid to the technical limitations of a fast introduction of the use of photovoltaic (PV) energy conversion. After a brief introduction on PV systems and the operation of a solar cell in chapter two, a state of the art is given of PV technology and possible price developments for PV modules and Balance-Of-System (BOS) components up to the year 2000 in chapters three and four. In chapter five the potential of installing grid-connected PV systems in the Netherlands is determined, taking into account the options of using existing buildings (PV systems on the roof), unexplored ground, in the verge of highways or railroads, industrial areas and airports. In chapter six non-economical bottlenecks for a large-scale introduction of grid-connected PV systems are discussed: the industrial production capacity for PV modules and other components, the fitting-in into the public electricity supply, and institutional aspects of installing PV systems on roofs. In chapter seven it is determined how much costs can be saved and CO 2 emission can be reduced when PV capacity is fitted-in into the Dutch electric power supply. The calculations are based on the Global Shift scenario. In chapter eight two scenarios (an optimistic scenario and a more realistic scenario) for the introduction of PV systems are outlined. For both scenarios the financial consequences and the contribution to the electric power supply are indicated. In chapter nine the net energy yield, being the result of the previously discussed introduction scenarios, is calculated, followed by a calculation of the avoided CO 2 emission, as well as the costs to avoid such emission. 25 figs., 15 tabs., 116 refs., 1 annex

  6. Fertilizers applied to certified organic tomato culture

    International Nuclear Information System (INIS)

    Martins, T.C.G.; De Nadai Fernandes, E.A.; Ferrari, A.A.; Bacchi, M.A.; Tagliaferro, F.S.

    2010-01-01

    The tomato culture demands large quantities of mineral nutrients, which are supplied by synthetic fertilizers in the conventional cultivation system. In the organic cultivation system only alternative fertilizers are allowed by the certifiers and accepted as safe for humans and environment. The chemical composition of rice bran, oyster flour, cattle manure and ground charcoal, as well as soils and tomato fruits were evaluated by instrumental neutron activation analysis (INAA). The potential contribution of organic fertilizers to the enrichment of chemical elements in soil and their transfer to fruits was investigated using concentration ratios for fertilizer and soil samples, and also for soil and tomato. Results evidenced that these alternative fertilizers could be taken as important sources of Br, Ca, Ce, K, Na and Zn for the organic tomato culture. (author)

  7. Variation in extragenic repetitive DNA sequences in Pseudomonas syringae and potential use of modified REP primers in the identification of closely related isolates

    Directory of Open Access Journals (Sweden)

    Elif Çepni

    2012-01-01

    Full Text Available In this study, Pseudomonas syringe pathovars isolated from olive, tomato and bean were identified by species-specific PCR and their genetic diversity was assessed by repetitive extragenic palindromic (REP-PCR. Reverse universal primers for REP-PCR were designed by using the bases of A, T, G or C at the positions of 1, 4 and 11 to identify additional polymorphism in the banding patterns. Binding of the primers to different annealing sites in the genome revealed additional fingerprint patterns in eight isolates of P. savastanoi pv. savastanoi and two isolates of P. syringae pv. tomato. The use of four different bases in the primer sequences did not affect the PCR reproducibility and was very efficient in revealing intra-pathovar diversity, particularly in P. savastanoi pv. savastanoi. At the pathovar level, the primer BOX1AR yielded shared fragments, in addition to five bands that discriminated among the pathovars P. syringae pv. phaseolicola, P. savastanoi pv. savastanoi and P. syringae pv. tomato. REP-PCR with a modified primer containing C produced identical bands among the isolates in a pathovar but separated three pathovars more distinctly than four other primers. Although REP-and BOX-PCRs have been successfully used in the molecular identification of Pseudomonas isolates from Turkish flora, a PCR based on inter-enterobacterial repetitive intergenic concensus (ERIC sequences failed to produce clear banding patterns in this study.

  8. Accelerating residential PV expansion: supply analysis for competitive electricity markets

    International Nuclear Information System (INIS)

    Payne, Adam; Williams, Robert H.; Duke, Richard

    2001-01-01

    Photovoltaic (PV) technology is now sufficiently advanced that market support mechanisms such as net metering plus a renewable portfolio standard (RPS) could induce rapid PV market growth in grid-connected applications. With such support mechanisms, markets would be sufficiently large that manufacturers could profitably build and operate 100 MW p /yr PV module factories, and electricity costs for residential rooftop PV systems would compare favorably with residential electricity prices in certain areas (e.g., California and the greater New York region in the US). This prospect is illustrated by economic and market analyses for one promising technology (amorphous silicon thin-film PV) from the perspectives of both module manufacturers and buyers of new homes with rooftop PV systems. With public policies that reflect the distributed and environmental benefits offered by PV-and that can sustain domestic PV market demand growth at three times the historical growth rate for a period of the order of two decades - PV could provide 3% of total US electricity supply by 2025. (Author)

  9. Changes in antioxidant and metabolite profiles during production of tomato paste

    NARCIS (Netherlands)

    Capanoglu, E.; Beekwilder, M.J.; Boyacioglu, D.; Hall, R.D.; Vos, de C.H.

    2008-01-01

    Tomato products and especially concentrated tomato paste are important sources of antioxidants in the Mediterranean diet. Tomato fruit contain well-known antioxidants such as vitamin C, carotenoids, flavonoids, and hydroxycinnamic acids. The industrial processing of this fruit into tomato paste

  10. KINETICS OF COLOUR CHANGE OF TOMATOES DURING DRYING

    Directory of Open Access Journals (Sweden)

    A. Unadi

    2016-10-01

    Full Text Available Colour is one of the pharameters determining the quality of dried tomatoes. The changes in colour of the skin of tomatoes during drying in an experimental dryer at various temperatures were measured every two hours by using Minolta CR 200 colorimeter and the colours were represented in Hunter-Lab scale. The objective of this research was develop a model for predicting colour changes of tomatoes during drying. The decrease in darkness as represented by dL value varied from 10 to 16%, while decrease in chroma value (dL varied from 20 to 37% of initial values. An empirical logarithmic equation with six constants was derived to fit the data of chroma changes during drying at various temperature and times. The model of colour change of tomatoes can be used for determining the optimum drying temperature to produce acceptable colour of dried tomatoes at reasonable cost.

  11. PV panel model based on datasheet values

    DEFF Research Database (Denmark)

    Sera, Dezso; Teodorescu, Remus; Rodriguez, Pedro

    2007-01-01

    This work presents the construction of a model for a PV panel using the single-diode five-parameters model, based exclusively on data-sheet parameters. The model takes into account the series and parallel (shunt) resistance of the panel. The equivalent circuit and the basic equations of the PV cell....... Based on these equations, a PV panel model, which is able to predict the panel behavior in different temperature and irradiance conditions, is built and tested....

  12. Good and bad practices in pv plants

    OpenAIRE

    Martinez Moreno, Francisco; Helleputte, F.; Tyutyundzhiev, N.; Rabal Echeverria, Daniel; Conlon, Michael; Fartaria, Tomás; Oteiza, David

    2013-01-01

    The PVCROPS project (PhotoVolta ic Cost r€duction, Reliability, Operational performance, Prediction and Simulation), cofinanced by European Commission in the frame of Seventh Framework Programme, has compiled in the “Good and bad practices: Manual to improve the quality and reduce the cost of PV systems” a collection of good and bad practices in actual PV plants . All the situations it collects represent the state-of-the-art of existing PV installations all around Europe. They show how ...

  13. Real Time Photovoltaic Array Simulator for Testing Grid-Connected PV Inverters

    DEFF Research Database (Denmark)

    Sera, Dezso; Valentini, Massimo; Raducu, Alin

    2008-01-01

    In this paper a real time flexible PV array simulator is presented. It is a system that can simulate different PV panel arrays in specific environmental conditions. To evaluate performance of the Maximum Power Point Tracking (MPPT) of grid-connected Photovoltaic (PV) inverters only measurements...... undertaken with an appropriate PV array simulator provide accurate and reproducible results. Thus the PV array simulator has been developed and implemented. MPPT efficiency tests on a commercial grid-connected PV inverter have been performed to validate the PV array simulator....

  14. Energy metrics analysis of hybrid - photovoltaic (PV) modules

    Energy Technology Data Exchange (ETDEWEB)

    Tiwari, Arvind [Department of Electronics and Communication, Krishna Institute of Engineering and Technology, 13 k.m. stone, Ghaziabad - Meerut Road, Ghaziabad 201 206, UP (India); Barnwal, P.; Sandhu, G.S.; Sodha, M.S. [Centre for Energy Studies, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110 016 (India)

    2009-12-15

    In this paper, energy metrics (energy pay back time, electricity production factor and life cycle conversion efficiency) of hybrid photovoltaic (PV) modules have been analyzed and presented for the composite climate of New Delhi, India. For this purpose, it is necessary to calculate (1) the energy consumption in making different components of the PV modules and (2) the annual energy (electrical and thermal) available from the hybrid-PV modules. A set of mathematical relations have been reformulated for computation of the energy metrics. The manufacturing energy, material production energy, energy use and distribution energy of the system have been taken into account, to determine the embodied energy for the hybrid-PV modules. The embodied energy and annual energy outputs have been used for evaluation of the energy metrics. For hybrid PV module, it has been observed that the EPBT gets significantly reduced by taking into account the increase in annual energy availability of the thermal energy in addition to the electrical energy. The values of EPF and LCCE of hybrid PV module become higher as expected. (author)

  15. Real time PV manufacturing diagnostic system

    Energy Technology Data Exchange (ETDEWEB)

    Kochergin, Vladimir [MicroXact Inc., Blacksburg, VA (United States); Crawford, Michael A. [MicroXact Inc., Blacksburg, VA (United States)

    2015-09-01

    The main obstacle Photovoltaic (PV) industry is facing at present is the higher cost of PV energy compared to that of fossil energy. While solar cell efficiencies continue to make incremental gains these improvements are so far insufficient to drive PV costs down to match that of fossil energy. Improved in-line diagnostics however, has the potential to significantly increase the productivity and reduce cost by improving the yield of the process. On this Phase I/Phase II SBIR project MicroXact developed and demonstrated at CIGS pilot manufacturing line a high-throughput in-line PV manufacturing diagnostic system, which was verified to provide fast and accurate data on the spatial uniformity of thickness, an composition of the thin films comprising the solar cell as the solar cell is processed reel-to-reel. In Phase II project MicroXact developed a stand-alone system prototype and demonstrated the following technical characteristics: 1) ability of real time defect/composition inconsistency detection over 60cm wide web at web speeds up to 3m/minute; 2) Better than 1mm spatial resolution on 60cm wide web; 3) an average better than 20nm spectral resolution resulting in more than sufficient sensitivity to composition imperfections (copper-rich and copper-poor regions were detected). The system was verified to be high vacuum compatible. Phase II results completely validated both technical and economic feasibility of the proposed concept. MicroXact’s solution is an enabling technique for in-line PV manufacturing diagnostics to increase the productivity of PV manufacturing lines and reduce the cost of solar energy, thus reducing the US dependency on foreign oil while simultaneously reducing emission of greenhouse gasses.

  16. Bacillus methylotrophicus Strain NKG-1, Isolated from Changbai Mountain, China, Has Potential Applications as a Biofertilizer or Biocontrol Agent.

    Science.gov (United States)

    Ge, Beibei; Liu, Binghua; Nwet, Thinn Thinn; Zhao, Wenjun; Shi, Liming; Zhang, Kecheng

    2016-01-01

    Chemical pesticides are widely used in agriculture, which endangers both environmental health and food safety. Biocontrol is an environmentally-friendly and cost-effective green technique in environmental protection and agricultural production; it generally uses selected bioresources, including beneficial microorganisms. We isolated a novel bacterial strain (NKG-1) from the rare dormant volcanic soils of Changbai Mountain in China's Jilin Province. The strain was identified as Bacillus methylotrophicus using morphological, biochemical, physiological, and phylogenetic 16S rDNA sequencing data. This strain was able to suppress mycelial growth and conidial germination of numerous plant pathogenic fungi on solid media. A greenhouse experiment showed that application of NKG-1 fermentation broth prior to inoculation of Botrytis cinerea, the cause of gray tomato mold, inhibited growth of the mold by 60%. Furthermore, application of a 100× dilution of NKG-1 fermentation broth to tomato seedlings yielded a significant increase in seedling fresh weight (27.4%), seedling length (12.5%), and root length (57.7%) compared to the control. When the same dosage was applied in the field, we observed increases in tomato plant height (14.7%), stem diameter (12.7%), crown width (16.3%), and maximum fruit diameter (11.5%). These results suggest that NKG-1 has potential commercial application as a biofertilizer or biocontrol agent.

  17. Methods for the Optimal Design of Grid-Connected PV Inverters

    DEFF Research Database (Denmark)

    Koutroulis, Eftichios; Blaabjerg, Frede

    2011-01-01

    and the efficient processing of this power by the DC/AC inverter. In this paper two new methods are presented for the optimal design of a PV inverter power section, output filter and MPPT control strategy. The influences of the electric grid regulations and standards as well as the PV array operational......The DC/AC inverters are used in grid-connected PV energy production systems as the power processing interface between the PV energy source and the electric grid. The energy injected into the electric grid by the PV installation depends on the amount of power extracted from the PV power source...

  18. Design Optimization of Transformerless Grid-Connected PV Inverters Including Reliability

    OpenAIRE

    Koutroulis, Eftichios; Blaabjerg, Frede

    2013-01-01

    This paper presents a new methodology for optimal design of transformerless photovoltaic (PV) inverters targeting a cost-effective deployment of grid-connected PV systems. The optimal switching frequency as well as the optimal values and types of the PV inverter components is calculated such that the PV inverter LCOE generated during the PV system lifetime period is minimized. The LCOE is also calculated considering the failure rates of the components, which affect the reliability performance...

  19. Terawatt Challenge for Thin-Film PV

    Energy Technology Data Exchange (ETDEWEB)

    Zweibel, K.

    2005-08-01

    The evolution of PV into one of the world's largest industries is not going to happen without major unforeseen problems. However, this study attempts to address the obvious ones, so that we can put aside the mythology of PV (for example, that it is only ''boutique power'' or that one must pave the world with it to be useful) and get on with changing the world's energy infrastructure. With the years of rapid market growth now under way in PV, the author is sure this will not be the last effort to understand the real potential and pitfalls of meeting the Challenge.

  20. Morphological and Molecular Identification of Colletotrichum acutatum from Tomato Fruit

    Directory of Open Access Journals (Sweden)

    Svetlana Živković

    2010-01-01

    Full Text Available Colletotrichum gloeosporioides, Colletotrichum acutatum, Colletotrichum coccodes, and Colletotrichum dematium are the four main species of Colletotrichum that cause tomato anthracnose. In Serbia, the occurrence of anthracnose on tomato fruit has been recorded during the last several years. Typical fruit symptoms include dark, sunken, and circular lesion with orange conidial masses. Pathogen isolates were obtained from a diseased tomato fruits, on PDA medium forming a white to gray colonies. The cultures developed black acervuli around the center of the colony. Conidia were hyaline, aseptate, and fusiform or rarely cylindrical. Appressoria were smooth, simple, clavate to ovate, and variedfrom light to dark brown. Pathogenicity tests with representative isolates were conducted on symptomless, detached tomato fruits. All tested isolates caused anthracnose lesions on tomato fruit after 7 days of incubation. Koch’s postulates were fulfilled by reisolationfrom inoculated tomato fruits. PCR analysis (using species-specific primer pair, CaInt2/ITS4 of genomic DNA from tomato isolates resulted in an amplification product of 490 bp, specific for C. acutatum, further confirming the identity of the pathogen. Based onmorphological and molecular characteristics, the isolates from tomato fruit were determined as C. acutatum.

  1. National survey report on PV power applications in Switzerland 2006

    International Nuclear Information System (INIS)

    Huesser, P.; Hostettler, T.

    2007-01-01

    This annual report was published by the Swiss Federal Office of Energy (SFOE) as part of the International Energy Agency's work on the exchange and dissemination of information on photovoltaic power systems (PVPS). The political situation in Switzerland with regard to the promotion of photovoltaics (PV) and new legislation in the energy area is discussed. The report provides information on installed PV power, costs and prices and the Swiss PV industry. Examples of PV applications are presented and data on the cumulative installed PV power in various application sectors is presented and discussed. Highlights, major projects and various demonstration and field-test programmes are dealt with, as are public budgets for market stimulation. Figures on the development, production and prices of PV cells and modules are presented. Swiss balance-of-system products are reviewed, as are PV-related services and the value of the Swiss PV business. A review of non-technical factors and new initiatives completes the report.

  2. National survey report on PV power applications in Switzerland 2006

    Energy Technology Data Exchange (ETDEWEB)

    Huesser, P. [Nova Energie GmbH, Aarau (Switzerland); Hostettler, T. [Ingenieurbuero Hostettler, Berne (Switzerland)

    2007-07-01

    This annual report was published by the Swiss Federal Office of Energy (SFOE) as part of the International Energy Agency's work on the exchange and dissemination of information on photovoltaic power systems (PVPS). The political situation in Switzerland with regard to the promotion of photovoltaics (PV) and new legislation in the energy area is discussed. The report provides information on installed PV power, costs and prices and the Swiss PV industry. Examples of PV applications are presented and data on the cumulative installed PV power in various application sectors is presented and discussed. Highlights, major projects and various demonstration and field-test programmes are dealt with, as are public budgets for market stimulation. Figures on the development, production and prices of PV cells and modules are presented. Swiss balance-of-system products are reviewed, as are PV-related services and the value of the Swiss PV business. A review of non-technical factors and new initiatives completes the report.

  3. Economics Of Tomato Production In Yewa North Local Government ...

    African Journals Online (AJOL)

    Questions relating to the socio-economic characteristics of the tomato farmers, tomato outputs, output prices and cost of resources viz. labour, seed, fertilizer and land used in production, as well as constraints to tomato production were asked in the questionnaire. Production function analysis was used to show the ...

  4. A Snapshot of the Emerging Tomato Genome Sequence

    Directory of Open Access Journals (Sweden)

    Lukas A. Mueller

    2009-03-01

    Full Text Available The genome of tomato ( L. is being sequenced by an international consortium of 10 countries (Korea, China, the United Kingdom, India, the Netherlands, France, Japan, Spain, Italy, and the United States as part of the larger “International Solanaceae Genome Project (SOL: Systems Approach to Diversity and Adaptation” initiative. The tomato genome sequencing project uses an ordered bacterial artificial chromosome (BAC approach to generate a high-quality tomato euchromatic genome sequence for use as a reference genome for the Solanaceae and euasterids. Sequence is deposited at GenBank and at the SOL Genomics Network (SGN. Currently, there are around 1000 BACs finished or in progress, representing more than a third of the projected euchromatic portion of the genome. An annotation effort is also underway by the International Tomato Annotation Group. The expected number of genes in the euchromatin is ∼40,000, based on an estimate from a preliminary annotation of 11% of finished sequence. Here, we present this first snapshot of the emerging tomato genome and its annotation, a short comparison with potato ( L. sequence data, and the tools available for the researchers to exploit this new resource are also presented. In the future, whole-genome shotgun techniques will be combined with the BAC-by-BAC approach to cover the entire tomato genome. The high-quality reference euchromatic tomato sequence is expected to be near completion by 2010.

  5. Effect of Tomato Industrial Processing on Phenolic Profile and Antiplatelet Activity

    Directory of Open Access Journals (Sweden)

    Iván Palomo

    2013-09-01

    Full Text Available Background: Regular consumption of fruits and vegetables (e.g., tomatoes has been shown to be beneficial in terms of reducing the incidence of cardiovascular diseases. The industrial processing of tomatoes into tomato-based products includes several thermal treatments. Very little is known on the effect of tomato industrial processing on antiaggregatory activity and phenolic profile. Methods: It was assessed the effect of tomato and by-products extracts on platelet aggregation induced by ADP, collagen, TRAP-6 and arachidonic acid. These in vitro antithrombotic properties were further supported in an in vivo model of thrombosis. A set of antiplatelet compounds has been selected for HPLC analysis in the different extracts. Results: Some natural compounds such as chlorogenic, caffeic, ferulic and p-coumaric acids were identified by HPLC in tomatoes and its products may inhibit platelet activation. Red tomatoes, tomato products (sauce, ketchup and juice and by-products extracts inhibited platelet aggregation induced adenosine 5'-diphosphate, collagen, thrombin receptor activator peptide-6 and arachidonic acid, but to a different extent. Also, pomace extract presents antithrombotic activity. Conclusions: Processed tomatoes may have a higher content of health-benefiting compounds than fresh ones. Pomace even presents the best antiplatelet activity. Finally, tomato products may be used as a functional ingredient adding antiplatelet activities to processed foods.

  6. Accelerating residential PV expansion: demand analysis for competitive electricity markets

    International Nuclear Information System (INIS)

    Duke, Richard; Williams, Robert; Payne, Adam

    2005-01-01

    This article quantifies the potential market for grid-connected, residential photovoltaic (PV) electricity integrated into new homes built in the US. It complements an earlier supply-side analysis by the authors that demonstrates the potential to reduce PV module prices below $1.5/W p by scaling up existing thin-film technology in 100 MW p /yr manufacturing facilities. The present article demonstrates that, at that price, PV modules may be cost effective in 125,000 new home installations per year (0.5 GW p /yr). While this market is large enough to support multiple scaled up thin-film PV factories, inefficient energy pricing and demand-side market failures will inhibit prospective PV consumers without strong public policy support. Net metering rules, already implemented in many states to encourage PV market launch, represent a crude but reasonable surrogate for efficient electricity pricing mechanisms that may ultimately emerge to internalize the externality benefits of PV. These public benefits include reduced air pollution damages (estimated costs of damage to human health from fossil fuel power plants are presented in Appendix A), deferral of transmission and distribution capital expenditures, reduced exposure to fossil fuel price risks, and increased electricity system reliability for end users. Thus, net metering for PV ought to be implemented as broadly as possible and sustained until efficient pricing is in place. Complementary PV 'buydowns' (e.g., a renewable portfolio standard with a specific PV requirement) are needed to jumpstart regional PV markets

  7. Development of Aloe vera based edible coating for tomato

    Science.gov (United States)

    Athmaselvi, K. A.; Sumitha, P.; Revathy, B.

    2013-12-01

    The effect of formulated Aloe vera based edible coating on mass loss, colour, firmness, pH, acidity, total soluble solid, ascorbic acid and lycopene on the coated tomato was investigated. The tomato in control showed a rapid deterioration with an estimated shelf life period of 19 days, based on the mass loss, colour changes, accelerated softening and ripening. On the contrary, the coating on tomatoes delayed the ripening and extended the shelf life up to 39 days. The physiological loss in weight was 7.6 and 15.1%, firmness was 36 and 46.2 N on 20th day for control and coated tomatoes, respectively. From the results, it was concluded that the use of Aloe vera based edible coating leads to increased tomato shelf-life.

  8. Do feed-in tariffs drive PV cost or viceversa?

    International Nuclear Information System (INIS)

    Antonelli, Marco; Desideri, Umberto

    2014-01-01

    Highlights: • The distribution of PV installations on the territory is not a function of the solar radiation. • Cost of PV plants were adapted to the FIT framework. • The FIT for PV in Italy was considered an incentive to financial investment. • The FIT for PV in Italy did not stimulate the development of national PV industry. - Abstract: A survey of the PV market in Italy was done studying a number of installations of different sizes whose economic data were known and assessed. The Italian market has experienced a boom in the PV market after the first mechanism of feed-in tariffs was promoted in 2005. The variations of the tariff structure in the following years have caused significant changes in the market structure in terms of average size and technical characteristics of installed plants. However, an Italian PV industry was not stimulated by the incentives and only companies involved in installation and maintenance were created. At the same time, the cost of the PV plants components, design and commissioning have followed quite a particular trend, which is more determined by the tariffs than by the market development and structure. It is quite clear that the costs of PV plants component are not driven by the amount of installations but by the tariffs, with a trend that follows the decreases in the incentives and not the global installed power. It is therefore very important to study the right tariff mechanisms and benefits to avoid financial disturbances on the market and to promote a real competitive market instead of a simple financial operation under a fake façade of green economy

  9. LukM/LukF'-PV is the most active Staphylococcus aureus leukotoxin on bovine neutrophils.

    Science.gov (United States)

    Barrio, Maria B; Rainard, Pascal; Prévost, Gilles

    2006-07-01

    Staphylococcus aureus is a ubiquitous pathogen causing infections in humans and domestic animals. It is often associated with bovine mastitis. Among secreted virulence factors, the leukotoxins constitute a family of toxins composed of two distinct subunits (class S and F proteins) which induce first Ca2+ influx and subsequent pore formation that allows ethidium entry. As mastitis-causing isolates harbor the genes of at least two, and often three leukotoxins, we compared the biological activities of the purified leukotoxins whose genes are found in mastitis-causing isolates on bovine polymorphonuclear neutrophils (PMN): spreading on a solid support, calcium influx and ethidium entry. In the spreading assay, the homologous pair LukM/LukF'-PV was the most active leukotoxin. Within each class, either S or F, subunits were interchangeable and generated leukotoxins with different specific activity. LukM was also very active when associated with heterologous F subunits. A similar ranking of homologous pairs was also found in the ethidium entry assay: LukM/LukF'-PV > HlgA/HlgB > HlgC/HlgB > LukE/LukD = LukEv/LukDv. In the Ca2+ flux assay, LukM/F'-PV was the most active pair, but gamma-hemolysin (Hlg) was also very efficient. LukEv/Dv was more active (twofold) than LukE/D in the spreading assay, but the two variants showed similar activities in the other two assays. Supposing that spreading and ethidium entry (pore formation) reflect toxic activities on bovine PMN, and Ca2+ influx cell activation, LukM/F'-PV was by far the most cytotoxic leukotoxin, but it was closely followed by gamma-hemolysin for PMN activation. These results suggest that LukM/F'-PV may constitute a particular virulence attribute of mastitis-causing S. aureus strains.

  10. Solar Energy: Incentives to Promote PV in EU27

    Directory of Open Access Journals (Sweden)

    María del P. Pablo-Romero

    2013-11-01

    Full Text Available The growth in the use of renewable energies in the EU has been remarkable. Among these energies is PV. The average annual growth rate for the EU-27 countries in installed PV capacity in the period 2005-2012 was 41.2%. While the installed capacity of PV has reached almost 82 % of National Renewable Energy Action Plan (NREAP targets for the EU-27 countries for 2020, it is still far from being used at its full potential. Over recent years, several measures have been adopted in the EU to enhance and promote PV. This paper undertakes a complete review of the state of PV power in Europe and the measures taken to date to promote it in EU-27. 25 countries have adopted measures to promote PV. The most widespread measure to promote PV use is Feed- in Tariffs. Tariffs are normally adjusted, in a decreasing manner, annually. Nevertheless, currently, seven countries have decided to accelerate this decrease rate in view of cost reduction of the installations and of higher efficiencies. The second instrument used to promote PV in the EU-27 countries is the concession of subsidies. Nevertheless, subsidies have the disadvantage of being closely linked to budgetary resources and therefore to budgetary constraints. In most EU countries, subsidies for renewable energy for PV are being lowered. Twelve EU-27 countries adopted tax measures. Low-interest loans and green certificate systems were only sparingly used.

  11. Kauai Island Utility Co-op (KIUC) PV integration study.

    Energy Technology Data Exchange (ETDEWEB)

    Ellis, Abraham; Mousseau, Tom (Knoxville, TN)

    2011-08-01

    This report investigates the effects that increased distributed photovoltaic (PV) generation would have on the Kauai Island Utility Co-op (KIUC) system operating requirements. The study focused on determining reserve requirements needed to mitigate the impact of PV variability on system frequency, and the impact on operating costs. Scenarios of 5-MW, 10-MW, and 15-MW nameplate capacity of PV generation plants distributed across the Kauai Island were considered in this study. The analysis required synthesis of the PV solar resource data and modeling of the KIUC system inertia. Based on the results, some findings and conclusions could be drawn, including that the selection of units identified as marginal resources that are used for load following will change; PV penetration will displace energy generated by existing conventional units, thus reducing overall fuel consumption; PV penetration at any deployment level is not likely to reduce system peak load; and increasing PV penetration has little effect on load-following reserves. The study was performed by EnerNex under contract from Sandia National Laboratories with cooperation from KIUC.

  12. A global strategy for the European PV industry

    International Nuclear Information System (INIS)

    Viaud, M.; Despotou, E.; Latour, M.; Hoffmann, W.; Macias, E.; Cameron, M.; Laborde, E.

    2004-01-01

    The objective was to develop a comprehensive strategy that answers to the need of today European PV industry. Namely: - Develop PV markets in Europe - Develop export markets. - Position the European PV industry within the European political environment and support the effort of national actors in their local objectives. This method lends itself to brainstorming to create actions and synergies, on order to achieve strategy objectives. The whole work is based on working groups clearly defined on the purpose, where all EPIA members are invited to participate. The overall first results are presented during the 19. EU PV Conference in Paris and EPIA will do recommendations on actions to be undertaken in the future. This strategy is co-financed by EPIA members and the 6. Framework Programme for research of the European Commission through the PV Catapult project. (authors)

  13. Differential impact of some Aspergillus species on Meloidogyne javanica biocontrol by Pseudomonas fluorescens strain CHA0.

    Science.gov (United States)

    Siddiqui, I A; Shaukat, S S; Khan, A

    2004-01-01

    The aim was to determine the influence of some Aspergillus species on the production of nematicidal agent(s) in vitro and biocontrol of Meloidogyne javanica in tomato by Pseudomonas fluorescens strains CHA0 and CHA0/pME3424. Six species of Aspergillus, isolated from the rhizosphere of certain crops, produced a variety of secondary metabolites in vitro. Culture filtrate (CF) obtained from Ps. fluorescens strain CHA0 and its2,4-diacetylphloroglucinol overproducing mutant CHA0/pME3424 grown in King's B liquid medium caused significant mortality of M. javanica juveniles in vitro. Bacterial growth medium amended with CF of A. niger enhanced nematicidal and beta-galactosidase activities of fluorescent pseudomonads while A. quadrilineatus repressed such activities. Methanol or ethyl acetate extracts of the CF of A. niger markedly optimized bacterial efficacy to cause nematode deaths while hexane extract of the fungus had no influence on the nematicidal activity of the bacterial strains. A. niger applied alone or in conjunction with the bacterial inoculants inhibited root-knot nematode galling in tomato. On the other hand, A. quadrilineatus used alone or together with CHA0 did not inhibit nematode galling but when used in combination with strain CHA0/pME3424 did reduce galling intensity. Aspergillus niger enhances the production of nematicidal compounds by Ps. fluorescensin vitro and improves biocontrol potential of the bacterial inoculants in tomato while A. quadrilineatus reduces bacterial performance to suppress root-knot nematodes. Rhizosphere harbours a variety of micro-organisms including bacteria, fungi and viruses. Aspergillus species are ubiquitous in most agricultural soils and generally produce a variety of secondary metabolites. Such metabolites synthesized by Aspergillus species may influence the production of nematicidal agents and subsequent biocontrol performance of the bacterial inoculants against plant-parasitic nematodes. This fact needs to be taken into

  14. A Practical Optimization Method for Designing Large PV Plants

    DEFF Research Database (Denmark)

    Kerekes, Tamas; Koutroulis, E.; Eyigun, S.

    2011-01-01

    Nowadays Photovoltaic (PV) plants have multi MW sizes, the biggest plants reaching tens of MW of capacity. Such large-scale PV plants are made up of several thousands of PV panels, each panel being in the range of 150-350W. This means that the design of a Large PV power plant is a big challenge...... and configuring such a plant should be implemented taking into consideration not only the cost of the installation, but also the Annual Energy Production, the Performance Ratio and the Levelized Cost Of Energy. In this paper, an algorithm is presented including the most important models of the PV system...

  15. PV investment in Europe

    Energy Technology Data Exchange (ETDEWEB)

    Hueser, Pius [Nova Energy GmbH, (Switzerland)

    2007-06-15

    This presentation is mainly about how the PV market in Europe has been growing, and which elements are going to determine if this market succeed or failed not only in Europe but also in the rest of the world. In the first part of this presentation, it is mentioned how in 2005 the development of some PV technologies triggered the PV market growth without any marketing control. Then, there are explained the aspects that changed such situation out of control, therefore, it emerged the beginning of the consolidation of this market. There are briefly explained those factors that are going to determine if this market succeed or failed in the future. Finally, there are given examples of some the PV investments. [Spanish] Esta presentacion habla principalmente de la manera en como ha crecido el Mercado de sistemas fotovoltaicos en Europa, asi tambien se mencionan los elementos fundamentales que determinaran el exito o fracaso de este mercado, no solamente en Europa sino tambien en el resto del mundo, en un futuro. En la primera parte de esta presentacion, se describe como en el 2005, debido al desarrollo de algunas tecnologias fotovoltaicas se desencadeno el crecimiento desenfrenado del mercado fotovoltaico. Despues, se explican los aspectos que hicieron que dicho crecimiento tomara su curso, teniendo como resultado el inicio de un mercado mas consolidado. Se explican brevemente los factores que determinaran si este mercado encuentra el exito o el fracaso en un futuro. Finalmente, se dan ejemplos de algunas adquisiciones fotovoltaicas.

  16. China PV Business and Applications Evaluation; TOPICAL

    International Nuclear Information System (INIS)

    Sherring, Chris

    1999-01-01

    This report provides an overview of photovoltaics (PV) business and applications in China. Although more than 70 million people in China are without access to grid electricity, many of the unelectrified regions benefit from considerable renewable resources, including good solar insolation. Current annual PV sales are still modest, however, and are estimated to be between 2.0 and 2.5 megawatts. This and other significant PV data, including information regarding the current status of key aspects of Chinese businesses, markets, and distribution channels, are included in the report. Detailed company profiles of Chinese business organizations and summaries of visits made to these companies (as well as to more remote sites in Inner Mongolia to examine PV usage by the end-use customer) in September-October 1998 are also presented

  17. 21 CFR 155.191 - Tomato concentrates.

    Science.gov (United States)

    2010-04-01

    ... Tomato concentrates. (a) Identity—(1) Definition. Tomato concentrates are the class of foods each of... greater in length. (c) Blemishes, such as dark brown or black particles (specks)—not more than four exceed...; place a U.S. No. 12 screen (1.68 millimeters (0.066 inch) openings) over the sink drain; transfer the...

  18. Rating PV Power and Energy: Cell, Module, and System Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Emery, Keith

    2016-06-02

    A summary of key points related to research-level measurements of current vs. voltage measurement theory including basic PV operation, equivalent circuit, and concept of spectral error; PV power performance including PV irradiance sensors, simulators and commercial and generic I-V systems; PV measurement artifacts, intercomparisons, and alternative rating methods.

  19. Production, Survival, and Evaluation of Solid-Substrate Inocula of Penicillium oxalicum, a Biocontrol Agent Against Fusarium Wilt of Tomato.

    Science.gov (United States)

    Larena, I; Melgarejo, P; De Cal, A

    2002-08-01

    ABSTRACT Production of conidia of Penicillium oxalicum (ATCC number pending), a biocontrol agent of Fusarium oxysporum f. sp. lycopersici, was tested in liquid and solid fermentation. P. oxalicum produced 250-fold more conidia in solid than in liquid fermentation at 30 days after inoculation of substrate. Solid fermentation was carried out in plastic bags (600 cm(3)) especially designed for solid fermentation (VALMIC) containing 50 g of peat/vermiculite (PV) (1:1, wt/wt) with 40% moisture, sealed, sterilized, and then inoculated with 1 ml of a conidial suspension of P. oxalicum (10(5) conidia g(-1) dry substrate), sealed again, and incubated in darkness at 20 to 25 degrees C for 30 days. Addition of amendments to PV in a proportion of 0.5 (wt/wt) significantly increased conidial production of P. oxalicum. The best production was obtained on PV plus meal of cereal grains (barley) or leguminous seeds (lentil) (100-fold higher). Conidial production obtained after 5 days of inoculation was similar to that obtained at 30 days. However, viability of conidia produced in PV plus lentil meal was 35% higher than that of conidia produced in PV plus barley meal. Changes in proportions (1:1:0.5, wt/wt/wt; 1:1:1, wt/wt/wt; 1:0.5:0.5, wt/wt/wt; 1:1:0.5, vol/vol/vol) of components of the substrate (peat/vermiculite/lentil meal) did not enhance production or viability of conidia. Optimal initial moisture in the substrate was 30 to 40%. At lower moistures, significant reductions of production of conidia were observed, particularly at 10%. There was a general decline in the number of conidia in bags with time of storage at -80, -20, 4, and 25 degrees C, or at room temperature (range from 30 to 15 degrees C), with the highest decline occurring from 60 to 180 days. Conidial viability also was reduced with time, except for conidia stored at -20 degrees C. Fresh conidia produced in solid fermentation system or those conidia stored at -20 degrees C for 180 days reduced Fusarium wilt of

  20. Effect of Dry Season Tomato Farming on Poverty Alleviation among ...

    African Journals Online (AJOL)

    Effect of Dry Season Tomato Farming on Poverty Alleviation among Women ... their major sources of resources for tomato farming, marketing and marketing ... and the effect of dry season tomato farming as strategy for poverty reduction; ...

  1. EPR study on tomatoes before and after gamma-irradiation

    International Nuclear Information System (INIS)

    Aleksieva, K.; Georgieva, L.; Tzvetkova, E.; Yordanov, N.D.

    2009-01-01

    The results from the EPR studies on fresh, air-dried and lyophilized tomato samples before and after gamma-irradiation are reported. Before irradiation fresh and air-dried tomatoes exhibit one singlet EPR line characterized with common g-factor of 2.0048±0.0005, whereas freeze-dried tomato does not show any EPR spectrum. After irradiation, a typical 'cellulose-like' triplet EPR spectrum appears in all samples, attributed to cellulose free radicals, generated by gamma-irradiation. It consists of intense central line with g=2.0048±0.0005 and two weak satellite lines separated ca. 3 mT left and right of it. In air-dried and lyophilized tomatoes the 'cellulose-like' EPR spectrum is superimposed by an additional partly resolved carbohydrate spectrum. Fading measurements of the radiation-induced EPR signals indicate that the intensity of the EPR spectra of air-dried and freeze-dried tomato are reduced to about 50% after 50 days, whereas those of fresh irradiated tomatoes kept at 4 o C fade completely in 15 days. The reported results unambiguously show that the presence of two satellite lines in the EPR 'cellulose-like' spectra of tomato samples can be used for identification of radiation processing.

  2. The molybdate-binding protein (ModA) of the plant pathogen Xanthomonas axonopodis pv. citri.

    Science.gov (United States)

    Balan, Andrea; Santacruz, Carolina P; Moutran, Alexandre; Ferreira, Rita C C; Medrano, Francisco J; Pérez, Carlos A; Ramos, Carlos H I; Ferreira, Luís C S

    2006-12-01

    The modABC operon of phytopathogen Xanthomonas axonopodis pv. citri (X. citri) encodes a putative ABC transporter involved in the uptake of the molybdate and tungstate anions. Sequence analyses showed high similarity values of ModA orthologs found in X. campestris pv. campestris (X. campestris) and Escherichia coli. The X. citri modA gene was cloned in pET28a and the recombinant protein, expressed in the E. coli BL21 (DE3) strain, purified by immobilized metal affinity chromatography. The purified protein remained soluble and specifically bound molybdate and tungstate with K(d) 0.29+/-0.12 microM and 0.58+/-0.14 microM, respectively. Additionally binding of molybdate drastically enhanced the thermal stability of the recombinant ModA as compared to the apoprotein. This is the first characterization of a ModA ortholog expressed by a phytopathogen and represents an important tool for functional, biochemical and structural analyses of molybdate transport in Xanthomonas species.

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

    Directory of Open Access Journals (Sweden)

    Mohamed Adam

    Full Text Available 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.

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

    Science.gov (United States)

    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.

  5. PV System Component Fault and Failure Compilation and Analysis.

    Energy Technology Data Exchange (ETDEWEB)

    Klise, Geoffrey Taylor; Lavrova, Olga; Gooding, Renee Lynne

    2018-02-01

    This report describes data collection and analysis of solar photovoltaic (PV) equipment events, which consist of faults and fa ilures that occur during the normal operation of a distributed PV system or PV power plant. We present summary statistics from locations w here maintenance data is being collected at various intervals, as well as reliability statistics gathered from that da ta, consisting of fault/failure distributions and repair distributions for a wide range of PV equipment types.

  6. MultiLocus Sequence Analysis- and Amplified Fragment Length Polymorphism-based characterization of xanthomonads associated with bacterial spot of tomato and pepper and their relatedness to Xanthomonas species.

    Science.gov (United States)

    Hamza, A A; Robene-Soustrade, I; Jouen, E; Lefeuvre, P; Chiroleu, F; Fisher-Le Saux, M; Gagnevin, L; Pruvost, O

    2012-05-01

    MultiLocus Sequence Analysis (MLSA) and Amplified Fragment Length Polymorphism (AFLP) were used to measure the genetic relatedness of a comprehensive collection of xanthomonads pathogenic to solaneous hosts to Xanthomonas species. The MLSA scheme was based on partial sequences of four housekeeping genes (atpD, dnaK, efp and gyrB). Globally, MLSA data unambiguously identified strains causing bacterial spot of tomato and pepper at the species level and was consistent with AFLP data. Genetic distances derived from both techniques showed a close relatedness of (i) X. euvesicatoria, X. perforans and X. alfalfae and (ii) X. gardneri and X. cynarae. Maximum likelihood tree topologies derived from each gene portion and the concatenated data set for species in the X. campestris 16S rRNA core (i.e. the species cluster comprising all strains causing bacterial spot of tomato and pepper) were not congruent, consistent with the detection of several putative recombination events in our data sets by several recombination search algorithms. One recombinant region in atpD was identified in most strains of X. euvesicatoria including the type strain. Copyright © 2012 Elsevier GmbH. All rights reserved.

  7. Examples of successful architectural integration of PV: Germany

    International Nuclear Information System (INIS)

    Hagemann, I.B.

    2004-01-01

    In Germany building-integrated photovoltaics (BIPV) are developing rapidly, and much progress has been achieved in the past five years. BIPV can be used today in different ways on both existing and new buildings. Architects and designers are discovering BIPV. With the help of custom-made products available on the German market they are beginning to explore the technical limits of an aesthetic and structural integration of PV in buildings. As a result some exciting high-profile building projects with PV have been built, for example, the small service pavilion Meereslauschen in Steinhude or the new headquarters building of the Wood Trade Association in Munich. These projects show that the use of PV is very varied and offers opportunities for creative architects. However non-technical problems still need to be solved to allow a meaningful and widespread application of PV in the built environment. To decrease costs it is essential to develop further standard BIPV components. The aim of such developments should be to replace standard PV modules by products in which PV and structural building elements are melded into one design and structural unit. (author)

  8. PV experience curves for the Netherlands

    International Nuclear Information System (INIS)

    Gerwig, R.

    2005-01-01

    Experience curves are one of several tools used by policy makers to take a look at market development. Numerous curves have been constructed for PV but none specific to the Netherlands. The objective of this report is to take a look at the price development of grid-connected PV systems in the Netherlands using the experience curve theory. After a literature and internet search and attempts to acquire information from PV companies information on 51% of the totally installed capacity was found. Curves for the period 1991-2001 were constructed based on system price, BOS (balance-of-system) price and inverter price. The progress ratio of the locally learning BOS was similar to the globally learning module market. This indicates that the pace of development of the Dutch PV market is similar to the globally followed pace. Improvement of the detail of the data might help to get a better idea of which BOS components have declined most. The similar progress ratio also shows the importance of investing both in module and system research as is the case in the Netherlands

  9. Optimal design of orientation of PV/T collector with reflectors

    International Nuclear Information System (INIS)

    Kostic, Lj.T.; Pavlovic, T.M.; Pavlovic, Z.T.

    2010-01-01

    Hybrid conversion of solar radiation implies simultaneous solar radiation conversion into thermal and electrical energy in the PV/Thermal collector. In order to get more thermal and electrical energy, flat solar radiation reflectors have been mounted on PV/T collector. To obtain higher solar radiation intensity on PV/T collector, position of reflectors has been changed and optimal position of reflectors has been determined by both experimental measurements and numerical calculation so as to obtain maximal concentration of solar radiation intensity. The calculated values have been found to be in good agreement with the measured ones, both yielding the optimal position of the flat reflector to be the lowest (5 o ) in December and the highest (38 o ) in June. In this paper, the thermal and electrical efficiency of PV/T collector without reflectors and with reflectors in optimal position have been calculated. Using these results, the total efficiency and energy-saving efficiency of PV/T collector have been determined. Energy-saving efficiency for PV/T collector without reflectors is 60.1%, which is above the conventional solar thermal collector, whereas the energy-saving efficiency for PV/T collector with reflectors in optimal position is 46.7%, which is almost equal to the values for conventional solar thermal collector. Though the energy-saving efficiency of PV/T collector decreases slightly with the solar radiation intensity concentration factor, i.e. the thermal and electrical efficiency of PV/T collector with reflectors are lower than those of PV/T collector without reflectors, the total thermal and electrical energy generated by PV/T collector with reflectors in optimal position are significantly higher than total thermal and electrical energy generated by PV/T collector without reflectors.

  10. Battery storage for PV power systems: an overview

    Energy Technology Data Exchange (ETDEWEB)

    Chaurey, A; Deambi, S [Tata Energy Research Inst., New Delhi (India)

    1992-06-01

    Batteries used in photovoltaic applications are required to have particular properties in order to minimize the system cost, in addition to meeting stringent reliability requirements associated with PV system installations. The battery sizing, installations, operation and maintenance, thus, are fundamentally different from those used in several other energy storage applications. The current paper gives an overview of battery systems commonly used in PV installation, as well as several new options which are found suitable or have been modified suitably to meet PV energy storage requirements. The systems are discussed briefly with respect to their construction, performance characteristics and compatibility with PV systems. The battery sizing procedures are also reviewed. (Author).

  11. Vision-based judgment of tomato maturity under growth conditions ...

    African Journals Online (AJOL)

    To determine the picking time of tomato and design the control strategy for the harvesting robot, the judgment of tomato maturity under natural conditions is ... Hue-mean and red-green color-difference image mean can be used as a criterion for the judgment of tomato maturity, and the tests indicated that the redgreen mean ...

  12. Assessing the PV business opportunities in Greece

    International Nuclear Information System (INIS)

    Patlitzianas, Konstantinos D.; Skylogiannis, Georgios K.; Papastefanakis, Dimitrios

    2013-01-01

    Highlights: • An approach of qualitative judgments for the PV opportunities through the assessing of the licenses’ value in Greece. • It can be supplied in other countries by applying different weights to the criteria. • It can be used by everyone in order to find a suitable PV investment without the need of experts in the field. - Abstract: Greece, as a member of the European Union (EU), has undertaken the obligation to meet the expected goals for the penetration of Renewable Energy Sources (RES) in the national energy balance in compliance with “20–20–20” goals (20% of the Gross Energy Consumption and 40% of the Gross Electricity Consumption should be covered by RES). Although the development of RES, and particularly of Photovoltaic (PV), in Greece during the last years has presented a satisfactory growth, the country is still far away from the above goals. The main reason for this delay is that – except the financial crisis – many licenses are inactive and waiting funding in order to be utilized. Additionally, the latest law (L.4152/2013) has forbidden the interconnection of new PV power Plants to the grid until the end of 2013. The above fact determines the significance of the existing PV Licenses in achieving the national goals. The aim of this paper is to present an integrated approach of qualitative judgments for the PV business opportunities through the assessing of the licenses’ value in Greece. The approach, which is based on a Multi Criteria Decision Making (MCDM) theory of quantifying multiple qualitative judgments, takes into account the real factors which can affect the expected production and cost of the PV installation and therefore the RoI (Return of Investment)

  13. Begomovirus diversity in tomato crops and weeds in Ecuador and the detection of a recombinant isolate of rhynchosia golden mosaic Yucatan virus infecting tomato.

    Science.gov (United States)

    Paz-Carrasco, Lenin C; Castillo-Urquiza, Gloria P; Lima, Alison T M; Xavier, Cesar A D; Vivas-Vivas, Leticia M; Mizubuti, Eduardo S G; Zerbini, F Murilo

    2014-08-01

    Viral diseases caused by begomoviruses are of economic importance due to their adverse effects on the production of tropical and subtropical crops. In Ecuador, despite reports of significant infestations of Bemisia tabaci in the late 1990s, only very recently has a begomovirus, tomato leaf deformation virus (ToLDeV, also present in Peru), been reported in tomato. ToLDeV is the first monopartite begomovirus discovered that originated in the Americas, and its presence in Ecuador highlights the need for a wider survey of tomato-infecting begomoviruses in this country. Tomato and weed samples were collected in 2010 and 2011 in six provinces of Ecuador, and begomovirus genomes were cloned and sequenced using a rolling-circle-amplification-based approach. Most tomato samples from the provinces of Guayas, Loja, Manabi and Santa Elena were infected with tomato leaf deformation virus (ToLDeV). One sample from Manabi had a triple infection with ToLDeV, rhynchosia golden mosaic Yucatan virus (RhGMYuV) and an isolate that was a recombinant between the two. A new begomovirus was detected in another tomato sample from Manabi. Samples of Rhynchosia sp. from the provinces of Guayas and Manabi were infected by RhGMYuV. These results indicate not only the prevalence of ToLDeV in tomato in Ecuador but also the presence of other viruses, albeit at a much lower frequency.

  14. Addressing firefighter safety around solar PV systems

    Energy Technology Data Exchange (ETDEWEB)

    Harris, B. [Sustainable Energy Technologies, Calgary, AB (Canada)

    2010-11-15

    The article discussed new considerations for installing photovoltaic (PV) systems that address the needs of fire service personnel. The presence of a PV system presents a multitude of dangers for firefighters, including electrical shock, the inhalation of toxic gases from being unable to cut a hole through the roof, falling debris and flying glass, and dead loading on a compromised structure and tripping on conduits. Mapping systems should be modified so that buildings with PV systems are identified for first responders, including firefighters who should learn that solar modules present an electrical hazard during the day but not at night; covering PV modules with foam or salvage covers may not shut the system down to a safe level; it takes a few moments for the power in PV modules to reduce to zero; and PV modules or conduit should never be cut, broke, chopped, or walked upon. The California Department of Forestry and Fire Protection recommends creating pathways and allowing easier access to the roof by setting the modules back from roof edges, creating a structurally sound pathway for firefighters to walk on and space to cut ventilation holes. However, the setback rule makes the economics of solar installation less viable for residential applications. The technological innovations aimed at addressing system safety all focus on limiting firefighter contact with live electrical components to within the extra-low-voltage (ELV) band. Some of the inverters on the market that support ELV system architecture were described. 1 fig.

  15. Performance Parameters for Grid-Connected PV Systems

    Energy Technology Data Exchange (ETDEWEB)

    Marion, B.; Adelstein, J.; Boyle, K.; Hayden, H.; Hammond, B.; Fletcher, T.; Canada, B.; Narang, D.; Shugar, D.; Wenger, H.; Kimber, A.; Mitchell, L.; Rich, G.; Townsend, T.

    2005-02-01

    The use of appropriate performance parameters facilitates the comparison of grid-connected photovoltaic (PV) systems that may differ with respect to design, technology, or geographic location. Four performance parameters that define the overall system performance with respect to the energy production, solar resource, and overall effect of system losses are the following: final PV system yield, reference yield, performance ratio, and PVUSA rating. These performance parameters are discussed for their suitability in providing desired information for PV system design and performance evaluation and are demonstrated for a variety of technologies, designs, and geographic locations. Also discussed are methodologies for determining system a.c. power ratings in the design phase using multipliers developed from measured performance parameters.The use of appropriate performance parameters facilitates the comparison of grid-connected photovoltaic (PV) systems that may differ with respect to design, technology, or geographic location. Four performance parameters that define the overall system performance with respect to the energy production, solar resource, and overall effect of system losses are the following: final PV system yield, reference yield, performance ratio, and PVUSA rating. These performance parameters are discussed for their suitability in providing desired information for PV system design and performance evaluation and are demonstrated for a variety of technologies, designs, and geographic locations. Also discussed are methodologies for determining system a.c. power ratings in the design phase using multipliers developed from measured performance parameters.

  16. Expression of heterosis in floral traits and fruit size in tomato ...

    African Journals Online (AJOL)

    The present research was prompted by lack of improved tomato cultivars adapted to the humid tropical. Tomato hybrids were developed by crossing wild and cultivated tomato varieties. The average fruit size of the tomato hybrids generated did not meet the level of acceptability in the local market. A modified three way cross ...

  17. Peeling mechanism of tomato under infrared heating

    Science.gov (United States)

    Critical behaviors of peeling tomatoes using infrared heat are thermally induced peel loosening and subsequent cracking. However, the mechanism of peel loosening and cracking due to infrared heating remains unclear. This study aimed at investigating the mechanism of peeling tomatoes under infrared h...

  18. Studies on improvement of tomato productivity in a large-scale greenhouse: Prediction of tomato yield based on integrated solar radiation

    International Nuclear Information System (INIS)

    Hisaeda, K.; Nishina, H.

    2007-01-01

    As there are currently many large-scale production facilities that have contracts with the large retailing companies, accurate prediction of yield is necessary. The present study developed a method to predict tomato yield accurately using the data on the outside solar radiation. The present study was conducted in a Venlo-type greenhouse (29,568 square m) at Sera Farm Co., Ltd. in Sera-cho in Hiroshima prefecture. The cultivar used for this experiment was plum tomato. The sowing took place on July 18, the planting took place on August 30, and the harvesting started on October 9, 2002. The planting density was 2.5 plants msup(-2). As the results of the analysis of correlation between the weekly tomato yield and the integrated solar radiation for the period from October 7 to July 28 (43 weeks), the highest correlation (r = 0.518) between the weekly tomato yield and the solar radiation integrated from seven to one weeks before the harvesting was observed. Further investigation by the same correlation analysis was conducted for the 25 weeks period from December 8 to May 26, during which time the effect of growing stages and air temperature were considered to be relatively small. The results showed the highest correlation (r = 0.730) between the weekly tomato yield and the solar radiation integrated from eight to one weeks before the harvesting. The tomato yield occasionally needed to be adjusted at Sera Farm. Consequently, the correlation between the three-week moving average of tomato yield and the integrated solar radiation was calculated. The results showed the highest correlation was obtained for the period from eight to one weeks before the harvesting (r = 0.860). This study therefore showed that it was possible to predict the tomato yield (y: kg.msup(-2).weeksup(-1)) using the following equation on the solar radiation integrated from eight to one weeks before the harvesting(x: MJ.msup(-2)): y = 7.50 x 10 sup(-6)x + 0.148 (rsup(2) = 0.740)

  19. A Software Tool for Optimal Sizing of PV Systems in Malaysia

    Directory of Open Access Journals (Sweden)

    Tamer Khatib

    2012-01-01

    Full Text Available This paper presents a MATLAB based user friendly software tool called as PV.MY for optimal sizing of photovoltaic (PV systems. The software has the capabilities of predicting the metrological variables such as solar energy, ambient temperature and wind speed using artificial neural network (ANN, optimizes the PV module/ array tilt angle, optimizes the inverter size and calculate optimal capacities of PV array, battery, wind turbine and diesel generator in hybrid PV systems. The ANN based model for metrological prediction uses four meteorological variables, namely, sun shine ratio, day number and location coordinates. As for PV system sizing, iterative methods are used for determining the optimal sizing of three types of PV systems, which are standalone PV system, hybrid PV/wind system and hybrid PV/diesel generator system. The loss of load probability (LLP technique is used for optimization in which the energy sources capacities are the variables to be optimized considering very low LLP. As for determining the optimal PV panels tilt angle and inverter size, the Liu and Jordan model for solar energy incident on a tilt surface is used in optimizing the monthly tilt angle, while a model for inverter efficiency curve is used in the optimization of inverter size.

  20. Delta Power Control Strategy for Multistring Grid-Connected PV Inverters

    DEFF Research Database (Denmark)

    Sangwongwanich, Ariya; Yang, Yongheng; Blaabjerg, Frede

    2017-01-01

    , is required for grid support (e.g., during frequency deviation). In this paper, a cost-effective solution to realize delta power control (DPC) for grid-connected PV systems is presented, where the multistring PV inverter configuration is adopted. This control strategy is a combination of maximum power point...... tracking (MPPT) and constant power generation (CPG) modes. In this control scheme, one PV string operating in the MPPT mode estimates the available power, whereas the other PV strings regulate the total PV power by the CPG control strategy in such a way that the delta power constraint for the entire PV...... system is achieved. Simulations and experiments have been performed on a 3-kW single-phase grid-connected PV system. The results have confirmed the effectiveness of the proposed DPC strategy, where the power reserve according to the delta power constraint is achieved under several operating conditions....

  1. Inactivation of Salmonella spp. on tomatoes by plant molecules.

    Science.gov (United States)

    Mattson, Tyler E; Johny, Anup Kollanoor; Amalaradjou, Mary Anne Roshni; More, Karen; Schreiber, David T; Patel, Jitu; Venkitanarayanan, Kumar

    2011-01-05

    The efficacy of carvacrol (CAR), trans-cinnamaldehyde (TC), eugenol (EUG) and β-resorcylic acid (BR) as a wash treatment for reducing Salmonella spp. on tomatoes was investigated. Plum tomatoes inoculated with a six-serotype mixture of Salmonella (10⁸CFU) were subjected to washing in sterile deionized water (control) or deionized water containing chlorine (100 ppm), CAR (0.25 and 0.75%), TC (0.5 and 0.75%), EUG (0.25 and 0.75%), or BR (0.75 and 1.0%) for 15 sec, 1 min, and 3 min. The plant molecules were more effective (Pwashing in water and chlorine. Both concentrations of CAR and TC, and 0.75% EUG decreased Salmonella counts on tomatoes by~6.0 log CFU/ml at 1 min. Both concentrations of BR decreased the pathogen on tomatoes to undetectable levels at 3 min of exposure. Washing of tomatoes in deionized water and chlorine for 3 min reduced Salmonella by ca. 2.0 and 4.0 log CFU/ml, respectively. No Salmonella was detected in the wash water containing the plant molecules or chlorine, whereas a substantial population of the pathogen survived in the control wash water. Moreover, none of the dipping treatments had any effect on the red color of tomatoes (P>0.05). Results indicate that CAR, TC, EUG and BR could effectively be used to kill Salmonella on tomatoes, but additional studies on sensory and quality characteristics of tomatoes treated with plant molecules are warranted. Copyright © 2010 Elsevier B.V. All rights reserved.

  2. The prospects for cost competitive solar PV power

    International Nuclear Information System (INIS)

    Reichelstein, Stefan; Yorston, Michael

    2013-01-01

    New solar Photovoltaic (PV) installations have grown globally at a rapid pace in recent years. We provide a comprehensive assessment of the cost competitiveness of this electric power source. Based on data available for the second half of 2011, we conclude that utility-scale PV installations are not yet cost competitive with fossil fuel power plants. In contrast, commercial-scale installations have already attained cost parity in the sense that the generating cost of power from solar PV is comparable to the retail electricity prices that commercial users pay, at least in certain parts of the U.S. This conclusion is shown to depend crucially on both the current federal tax subsidies for solar power and an ideal geographic location for the solar installation. Projecting recent industry trends into the future, we estimate that utility-scale solar PV facilities are on track to become cost competitive by the end of this decade. Furthermore, commercial-scale installations could reach “grid parity” in about ten years, if the current federal tax incentives for solar power were to expire at that point. - Highlights: ► Assessment of the cost competitiveness of new solar Photovoltaic (PV) installations. ► Utility-scale PV installations are not yet cost competitive with fossil fuel power plants. ► Commercial-scale installations have already attained cost parity in certain parts of the U.S. ► Utility-scale solar PV facilities are on track to become cost competitive by the end of this decade

  3. Overview of Recent Grid Codes for PV Power Integration

    DEFF Research Database (Denmark)

    Craciun, Bogdan-Ionut; Kerekes, Tamas; Sera, Dezso

    2012-01-01

    The challenge to bring down the cost of produced photovoltaic (PV) power had a major impact on the PV market and in consequence the grid operators experienced higher and higher PV power penetration. The growing share of this decentralized generation plants started to affect the grid stability...

  4. Evaluation of Resistance to Ralstonia solanacearum in Tomato Genetic Resources at Seedling Stage

    Directory of Open Access Journals (Sweden)

    Sang Gyu Kim

    2016-02-01

    Full Text Available Bacterial wilt of tomatoes caused by Ralstonia solanacearum is a devastating disease that limits the production of tomato in Korea. The best way to control this disease is using genetically resistant tomato plant. The resistance degree to R. solanacearum was evaluated for 285 tomato accessions conserved in the National Agrobiodiversity Center of Rural Development Administration. These accessions of tomato were originated from 23 countries. Disease severity of tomato accessions was investigated from 7 days to 14 days at an interval of 7 days after inoculation of R. solanacearum under greenhouse conditions. A total of 279 accessions of tomato germplasm were susceptible to R. solanacearum, resulting in wilt and death in 70 to 90% of these plants. Two tomato accessions were moderately resistant to R. solanacearum. Only four accessions showed high resistance against R. solanacearum. No distinct symptom of bacterial wilt appeared on the resistant tomato germplasms for up to 14 days after inoculation of R. solanacearum. Microscopy of resistant tomato stems infected with R. solanacearum revealed limited bacterial spread with thickening of pit membrane and gum production. Therefore, these four resistant tomato germplasms could be used in tomato breeding program against bacterial wilt.

  5. LonWorks as Fieldbus for PV-Installations; LonWorks als Feldbus fuer PV-Anlagen

    Energy Technology Data Exchange (ETDEWEB)

    Bergen, Ch. von

    2003-07-01

    The growing market for photovoltaics increasingly requires suitable quality controls covering plant operators, planners and installers, as well as the electric utilities. Additionally, the interest of the general public in the behaviour of photovoltaic (PV) plants is growing. This includes information from everyday practice. Alongside data retrieval, other themes such as the operative management of the unit and energy management become increasingly important for grid-connected PV systems. Todays measuring systems are not compatible with each other. Data communication between different PV plants with computer-aided analysis- and visualisation programmes is very complicated. LonWorks was introduced by Motorola and Toshiba in 1991. Today it leads the world market for field bus systems. With plug and play, components by several manufacturers can easily be incorporated into a LonWorks network. Today more than 3,500 companies use LonWorks technology. The goal of this project is to introduce the very popular LonWorks technology as a new standard for PV applications. The first objective was to develop a LonWorks interface for our Convert inverters and to connect them into a small network. In a second step we installed a LonWorks system at the 260 kW{sub p} PV plant 'Felsenau' in Berne, Switzerland. All 68 inverters are controlled over power line with LonWorks. The on-site PC acts as LonWorks DataServer and making remote information monitoring and data gathering possible. As soon as a functional error occurs, an alarm will be transmitted via modem to the SMSC (Short Message Service Centre). After two years of operation we can say that all expectations were fulfilled by our new system. Knowledge gained from this project has shown that LonWorks has lived up its considerable promise and can be regarded as a high-quality piece of technology. Integration into an overall system is technically very easy. To do this, however, relatively expensive software solutions have

  6. Performance analysis of PV panel under varying surface temperature

    Directory of Open Access Journals (Sweden)

    Kumar Tripathi Abhishek

    2018-01-01

    Full Text Available The surface temperature of PV panel has an adverse impact on its performance. The several electrical parameters of PV panel, such as open circuit voltage, short circuit current, power output and fill factor depends on the surface temperature of PV panel. In the present study, an experimental work was carried out to investigate the influence of PV panel surface temperature on its electrical parameters. The results obtained from this experimental study show a significant reduction in the performance of PV panel with an increase in panel surface temperature. A 5W PV panel experienced a 0.4% decrease in open circuit voltage for every 1°C increase in panel surface temperature. Similarly, there was 0.6% and 0.32% decrease in maximum power output and in fill factor, respectively, for every 1°C increase in panel surface temperature. On the other hand, the short circuit current increases with the increase in surface temperature at the rate of 0.09%/°C.

  7. Mycorrhizal Dependency and Response of Tomato ( Lycopersicon ...

    African Journals Online (AJOL)

    A pot experiment was conducted on tomato (Lycopersicon esculentum) to evaluate the responses of tomato to inoculation of mycorrhiza (AMF) under different levels of soil phosphorus (P) concentrations in a greenhouse study. The results showed different responses on dry matter yield, shoot phosphorus concentration, ...

  8. Solar photovoltaic (PV) energy; latest developments in the building integrated and hybrid PV systems

    International Nuclear Information System (INIS)

    Zahedi, A.

    2006-01-01

    Environmental concerns are growing and interest in environmental issues is increasing and the idea of generating electricity with less pollution is becoming more and more attractive. Unlike conventional generation systems, fuel of the solar photovoltaic energy is available at no cost. And solar photovoltaic energy systems generate electricity pollution-free and can easily be installed on the roof of residential as well as on the wall of commercial buildings as grid-connected PV application. In addition to grid-connected rooftop PV systems, solar photovoltaic energy offers a solution for supplying electricity to remote located communities and facilities, those not accessible by electricity companies. The interest in solar photovoltaic energy is growing worldwide. Today, more than 3500MW of photovoltaic systems have been installed all over the world. Since 1970, the PV price has continuously dropped [8]. This price drop has encouraged worldwide application of small-scale residential PV systems. These recent developments have led researchers concerned with the environment to undertake extensive research projects for harnessing renewable energy sources including solar energy. The usage of solar photovoltaic as a source of energy is considered more seriously making future of this technology looks promising. The objective of this contribution is to present the latest developments in the area of solar photovoltaic energy systems. A further objective of this contribution is to discuss the long-term prospect of the solar photovoltaic energy as a sustainable energy supply. [Author

  9. Mutant lines of currant tomato, valuable germplasm with multiple disease resistance

    International Nuclear Information System (INIS)

    Govorova, G.F.; Khrustaleva, V.V.; Shcherbakov, V.K.

    1987-01-01

    Studies were carried out for two years on eight mutant lines of currant tomato at the Krymsk Experimental Breeding Station of the N.I. Vavilov All-Union Scientific Research Institute of Plant-Growing (VIR). The station is situated in an area of commercial field tomato growing (Krasnodar region). The mutant lines of currant tomato (VIR specimen No. k-4053) were obtained through chronic gamma-irradiation. A disease resistance evaluation of the mutants was carried out for Verticillium wilt (Verticillium albo-atrum Rein. and Berth.), for black bacterial spotting (Xanthomonas vesicatoria Dows.), for tobacco mosaic virus Nicotiana 1 Smith), for streak virus (Nicotiana 1), for the combination TMV with X and Y potato viruses, for cucumber virus (Cucumis 1), and also for top rot. Fifty plants of each mutant line were evaluated and checks were made three times in each season. A comparison of the currant tomato mutants with the standard tomato varieties demonstrates the better resistance shown by the mutant germplasm to the main pathogens. The degree to which some currant tomato mutants were affected by Verticillium was lower than that of the most VerticiIlium-resistant samples of tomato evaluated between 1975 and 1981. The mutants of currant tomato should therefore be of interest as germplasm in breeding tomatoes for improved multiple disease resistance

  10. Superfamily of ankyrin repeat proteins in tomato.

    Science.gov (United States)

    Yuan, Xiaowei; Zhang, Shizhong; Qing, Xiaohe; Sun, Meihong; Liu, Shiyang; Su, Hongyan; Shu, Huairui; Li, Xinzheng

    2013-07-10

    The ankyrin repeat (ANK) protein family plays a crucial role in plant growth and development and in response to biotic and abiotic stresses. However, no detailed information concerning this family is available for tomato (Solanum lycopersicum) due to the limited information on whole genome sequences. In this study, we identified a total of 130 ANK genes in tomato genome (SlANK), and these genes were distributed across all 12 chromosomes at various densities. And chromosomal localizations of SlANK genes indicated 25 SlANK genes were involved in tandem duplications. Based on their domain composition, all of the SlANK proteins were grouped into 13 subgroups. A combined phylogenetic tree was constructed with the aligned SlANK protein sequences. This tree revealed that the SlANK proteins comprise five major groups. An analysis of the expression profiles of SlANK genes in tomato in different tissues and in response to stresses showed that the SlANK proteins play roles in plant growth, development and stress responses. To our knowledge, this is the first report of a genome-wide analysis of the tomato ANK gene family. This study provides valuable information regarding the classification and putative functions of SlANK genes in tomato. Crown Copyright © 2013. Published by Elsevier B.V. All rights reserved.

  11. A strategic model for PV dissemination in Thailand

    Energy Technology Data Exchange (ETDEWEB)

    Hiranvarodom, S. [Rajamangala Inst. of Technology, Dept. of Electrical Engineering, Pathumthani (Thailand); Hill, R. [University of Northumbria, Newcastle Photovoltaics Applications Centre, Newcastle upon Tyne (United Kingdom); O' Keefe, P. [University of Northumbria, Dept. of Geography and Environmental Management, Newcastle upon Tyne (United Kingdom)

    1999-07-01

    The process of information dissemination is necessary for the successful implementation for photovoltaic (PV) programmes in developing countries, and it is essential to consider the strategies for implementation of a PV project to ensure that it will be successful. This paper proposes a strategic model for PV dissemination in Thailand and discusses the roles of key players in the implementation of the strategy and the responsibilities of these organisations. (Author)

  12. The world PV market 2000: shifting from subsidy to 'fully economic'?

    International Nuclear Information System (INIS)

    Maycock, Paul

    2000-01-01

    This article presents an overview of the world grid-connected photovoltaic (PV) market concentrating on the US, Japan and Germany. The PV markets in the three countries are examined, and PV module shipments, the economics of residential PVs in the markets, and forecasts of the grid-connected market are discussed. Details are given of the German 100,000 roofs PV roof subsidy programme to stimulate the residential and commercial grid-connected market. A summary of the grid-connected PV markets in the three countries, and economic information on German grid-connected PV roofs are tabulated

  13. Burkholderia caballeronis sp. nov., a nitrogen fixing species isolated from tomato (Lycopersicon esculentum) with the ability to effectively nodulate Phaseolus vulgaris.

    Science.gov (United States)

    Martínez-Aguilar, Lourdes; Salazar-Salazar, Corelly; Méndez, Rafael Díaz; Caballero-Mellado, Jesús; Hirsch, Ann M; Vásquez-Murrieta, María Soledad; Estrada-de los Santos, Paulina

    2013-12-01

    During a survey of Burkholderia species with potential use in agrobiotechnology, a group of 12 strains was isolated from the rhizosphere and rhizoplane of tomato plants growing in Mexico (Nepantla, Mexico State). A phylogenetic analysis of 16S rRNA gene sequences showed that the strains are related to Burkholderia kururiensis and Burkholderia mimosarum (97.4 and 97.1 %, respectively). However, they induced effective nitrogen-fixing nodules on roots of Phaseolus vulgaris. Based on polyphasic taxonomy, the group of strains represents a novel species for which the name Burkholderia caballeronis sp. nov. is proposed. The type species is TNe-841(T) (= LMG 26416(T) = CIP 110324(T)).

  14. Economic perspective of PV electricity in Oman

    International Nuclear Information System (INIS)

    Al-Badi, A.H.; Albadi, M.H.; Al-Lawati, A.M.; Malik, A.S.

    2011-01-01

    Solar and wind energies are likely to play an important role in the future energy generation in Oman. This paper utilizes average daily global solar radiation and sunshine duration data of 25 locations in Oman to study the economic prospects of solar energy. The study considers a solar PV power plant of 5-MW at each of the 25 locations. The global solar radiation varies between slightly greater than 4 kWh/m 2 /day at Sur to about 6 kWh/m 2 /day at Marmul while the average value in the 25 locations is more than 5 kWh/m 2 /day. The results show that the renewable energy produced each year from the PV power plant varies between 9000 MWh at Marmul and 6200 MWh at Sur while the mean value is 7700 MWh of all the 25 locations. The capacity factor of PV plant varies between 20% and 14% and the cost of electricity varies between 210 US$/MWh and 304 US$/MWh for the best location to the least attractive location, respectively. The study has also found that the PV energy at the best location is competitive with diesel generation without including the externality costs of diesel. Renewable energy support policies that can be implemented in Oman are also discussed. -- Research highlights: → The global solar radiation values for 25 locations in Oman are obtained using satellite data that are corrected by data from ground stations. → The study considers a solar PV power plant of 5-MW to calculate the capacity factor (CF) and the cost of energy (COE) at each of the 25 locations. → The study has found that the CF of PV plant varies between 20% and 14% and the corresponding COE varies between 210 US$/MWh and 304 US$/MWh for the best location to the least attractive location, respectively. → The study has found that the PV energy at the best location is competitive with diesel generation without including the externality costs of diesel. → Since PV energy is not competitive with fossil fuel-based generation in most locations renewable energy support mechanisms have been

  15. Photovoltaic (PV) contribution to the primary frequency control

    International Nuclear Information System (INIS)

    Rafa, Adel Hamad

    2012-01-01

    Photovoltaic (PV) technology is among the most efficient and cost effective renewable energy kinds currently available on the market. The connection of a large number of PVs to the grid may influence the frequency and voltage stability of the power system. This paper proposes load-frequency control technique for system with high penetration of photovoltaic (PV). The proposed controller has been successfully implemented and tested using PSCAD/EMTDC. In this study, the impact of photovoltaic (PV) on frequency stability of the system is studies in detail. This study shows that large penetration of photovoltaic (PV) with load and frequency control has a significant impact on the stability and security level of electrical network.(author)

  16. Digitization and Visualization of Greenhouse Tomato Plants in Indoor Environments

    Directory of Open Access Journals (Sweden)

    Dawei Li

    2015-02-01

    Full Text Available This paper is concerned with the digitization and visualization of potted greenhouse tomato plants in indoor environments. For the digitization, an inexpensive and efficient commercial stereo sensor—a Microsoft Kinect—is used to separate visual information about tomato plants from background. Based on the Kinect, a 4-step approach that can automatically detect and segment stems of tomato plants is proposed, including acquisition and preprocessing of image data, detection of stem segments, removing false detections and automatic segmentation of stem segments. Correctly segmented texture samples including stems and leaves are then stored in a texture database for further usage. Two types of tomato plants—the cherry tomato variety and the ordinary variety are studied in this paper. The stem detection accuracy (under a simulated greenhouse environment for the cherry tomato variety is 98.4% at a true positive rate of 78.0%, whereas the detection accuracy for the ordinary variety is 94.5% at a true positive of 72.5%. In visualization, we combine L-system theory and digitized tomato organ texture data to build realistic 3D virtual tomato plant models that are capable of exhibiting various structures and poses in real time. In particular, we also simulate the growth process on virtual tomato plants by exerting controls on two L-systems via parameters concerning the age and the form of lateral branches. This research may provide useful visual cues for improving intelligent greenhouse control systems and meanwhile may facilitate research on artificial organisms.

  17. Photovoltaic-thermal (PV/T) solar collectors: Features and performance modelling

    International Nuclear Information System (INIS)

    Atienza-Márquez, Antonio; Bruno, Joan Carles; Coronas, Alberto; Korolija, Ivan; Greenough, Richard; Wright, Andy

    2017-01-01

    Currently, the electrical efficiency of photovoltaic (PV) solar cells ranges between 5–25%. One of the most important parameters that affects the electrical efficiency of a PV collector is the temperature of its cells: the higher temperature, the lower is the efficiency. Photovoltaic/thermal (PV/T) technology is a potential solution to ensure an acceptable solar energy conversion. The PV/T technology produces both electrical and thermal energy simultaneously. It is suitable for low temperature applications (25–40 o C) and overall efficiency increases compared to individual collectors. This paper describes an installation in a single-family house where PV/T collectors are coupled with a ground heat exchanger and a heat pump for domestic hot water and space heating purposes. The aim of this work is twofold. First, the features of the PV/T technology are analyzed. Second, a model of a flat-plate PV/T water collector was developed in TRNSYS in order to analyze collectors performance. (author)

  18. Tomato whole genome transcriptional response to Tetranychus urticae identifies divergence of spider mite-induced responses between tomato and Arabidopsis

    NARCIS (Netherlands)

    Martel, C.; Zhurov, V.; Navarro, M.; Martinez, M.; Cazaux, M.; Auger, P.; Migeon, A.; Santamaria, M.E.; Wybouw, N.; Diaz, I.; Van Leeuwen, T.; Navajas, M.; Grbic, M.; Grbic, V.

    2015-01-01

    The two-spotted spider mite Tetranychus urticae is one of the most significant mite pests in agriculture, feeding on more than 1,100 plant hosts, including model plants Arabidopsis thaliana and tomato, Solanum lycopersicum. Here, we describe timecourse tomato transcriptional responses to spider mite

  19. GRAFT TAKES OF TOMATO ON OTHER SOLANACEOUS PLANTS

    Directory of Open Access Journals (Sweden)

    ANDRÉ RICARDO ZEIST

    2017-01-01

    Full Text Available This paper aimed to assess tomato grafting on different solanaceous species through two grafting methods. Scions were cut from cultivar Santa Cruz Kada seedlings. A fully randomized experimental design was carried out with treatments in a 9 x 2 factorial scheme. As rootstocks, four accessions of mini - tomatoes (0224 - 53, RVTC 57, RVTC 20 and 6889 - 50 - Solanum lycopersicum L; two species of wild tomato ( Solanum habrochaites var hirsutum ‘PI - 127826’ and Solanum pennellii ‘LA716’; other two tomato species [ Solanum, cocona ( Solanum sessiliflorum and physalis ( Physalis peruviana ] and a control with cultivar Santa Cruz Kada (auto - graft rootstocks were used. In addition, two grafting methods were evaluated full cleft and approach graft. Fifteen days after grafting, plants were assessed for graft - take percentage; root length; plant height; leaf number; foliar area; root, stem and leaf dry matter; and ratio between shoot and root dry matter. Based on the results, we may state rootstock and grafting interaction had effect on both graft - take rate and plant development. Overall, the studied plants should be recommended as rootstock, except for 6889 - 50 mini - tomato ( S. lycopersicum L. and S. pennellii . Full cleft grafting was most suitable for cocona and physalis, while the approach method showed better results for the mini - tomato accessions 0224 - 53, RVTC 57 and RVTC 20, as well as for S. habrochaites .

  20. 75 FR 4817 - Beauveria Bassiana Strain GHA; Notice of Receipt of a Request for an Amendment to Delete a Use in...

    Science.gov (United States)

    2010-01-29

    ... ENVIRONMENTAL PROTECTION AGENCY [EPA-HQ-OPP-2010-0029; FRL-8809-2] Beauveria Bassiana Strain GHA; Notice of Receipt of a Request for an Amendment to Delete a Use in a Pesticide Registration AGENCY... Beauveria bassiana Tomato Strain GHA Users of this product who desire continued use on the crop being...

  1. Salicylic Acid Is Involved in the Basal Resistance of Tomato Plants to Citrus Exocortis Viroid and Tomato Spotted Wilt Virus.

    Science.gov (United States)

    López-Gresa, M Pilar; Lisón, Purificación; Yenush, Lynne; Conejero, Vicente; Rodrigo, Ismael; Bellés, José María

    2016-01-01

    Tomato plants expressing the NahG transgene, which prevents accumulation of endogenous salicylic acid (SA), were used to study the importance of the SA signalling pathway in basal defence against Citrus Exocortis Viroid (CEVd) or Tomato Spotted Wilt Virus (TSWV). The lack of SA accumulation in the CEVd- or TSWV-infected NahG tomato plants led to an early and dramatic disease phenotype, as compared to that observed in the corresponding parental Money Maker. Addition of acibenzolar-S-methyl, a benzothiadiazole (BTH), which activates the systemic acquired resistance pathway downstream of SA signalling, improves resistance of NahG tomato plants to CEVd and TSWV. CEVd and TSWV inoculation induced the accumulation of the hydroxycinnamic amides p-coumaroyltyramine, feruloyltyramine, caffeoylputrescine, and feruloylputrescine, and the defence related proteins PR1 and P23 in NahG plants earlier and with more intensity than in Money Maker plants, indicating that SA is not essential for the induction of these plant defence metabolites and proteins. In addition, NahG plants produced very high levels of ethylene upon CEVd or TSWV infection when compared with infected Money Maker plants, indicating that the absence of SA produced additional effects on other metabolic pathways. This is the first report to show that SA is an important component of basal resistance of tomato plants to both CEVd and TSWV, indicating that SA-dependent defence mechanisms play a key role in limiting the severity of symptoms in CEVd- and TSWV-infected NahG tomato plants.

  2. Temperature field for radiative tomato peeling

    International Nuclear Information System (INIS)

    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. (paper)

  3. Impact of Rooftop Solar PV on Residential Distribution Network

    DEFF Research Database (Denmark)

    Bhattarai, Bishnu Prasad; Bak-Jensen, Birgitte; Pillai, Jayakrishnan Radhakrishna

    Increased environmental awareness in recent years has encouraged rapid growth of renewable energy sources especially solar PV and wind. Among them, small scale solar PV has been gaining more momentum especially at residential level. Even today moderate penetration of grid tied rooftop solar PV has...... become reality in many countries. In spite of various benefits, higher penetration of rooftop PVs might come up with number of detrimental effects, with power quality and overcurrent protection being the major ones. Therefore, it is reasonable to quantify both drawback and benefits of rooftop PV...

  4. Improving the efficiency of photovoltaic (PV) panels by oil coating

    International Nuclear Information System (INIS)

    Abd-Elhady, M.S.; Fouad, M.M.; Khalil, T.

    2016-01-01

    Highlights: • It is possible to improve the efficiency of PV panels by increasing the amount of light transmitted to the panel. • Coating PV panels by a fine layer of Labovac oil increases the amount of sun light transmitted to the panel. • Coating PV panels by a fine layer of Labovac oil increases the power output of the panel. • Coating PV panels with a layer of Labovac oil has to be applied in cold countries and not in hot regions. - Abstract: The objective of this research is to develop a new technique for improving the efficiency of Photovoltaic (PV) panels. This technique is done by coating the front surface of the PV panel by a fine layer of oil in order to increase the amount of light transmitted to the panel, and consequently its efficiency. Different types of oils are examined, including both mineral oils and natural oils. In case of mineral oils; vacuum pump oil (Labovac oil), engine oil (Mobil oil) and brake oil (Abro oil) are examined, while in case of natural oils; olive and sunflower oils are examined. An experimental setup has been developed to examine the performance of the PV panels as a function of oil coatings. The experimental setup consists of an artificial sun, the PV panel under investigation, a cooling system and a measuring system to measure the performance of the panel. It has been found that coating the PV panel with a fine layer of Labovac oil, ∼1 mm thick, improves the efficiency of the PV panel by more than 20%, and this is due to the high transmissivity of the Labovac oil compared to other oils. However, the Labovac oil has a drawback which is overheating of the panel due to its high transmissivity. Coating of PV panels with a fine layer of Labovac oil should be done only in cold regions, in order to avoid the heating effect that can decrease the power output of PV panels.

  5. Assessing the influence of the temporal resolution of electrical load and PV generation profiles on self-consumption and sizing of PV-battery systems

    International Nuclear Information System (INIS)

    Beck, T.; Kondziella, H.; Huard, G.; Bruckner, T.

    2016-01-01

    Highlights: • MILP optimization model for operation and investment of PV-battery systems. • Use of high resolution (10 s) electrical household load and PV generation profiles. • Analysis of influence of temporal resolution on self-consumption and optimal sizing. • Electrical load profile characteristics influence required temporal resolution. - Abstract: The interest in self-consumption of electricity generated by rooftop photovoltaic systems has grown in recent years, fueled by decreasing levelized costs of electricity and feed-in tariffs as well as increasing end customer electricity prices in the residential sector. This also fostered research on grid-connected PV-battery storage systems, which are a promising technology to increase self-consumption. In this paper a mixed-integer linear optimization model of a PV-battery system that minimizes the total discounted operating and investment costs is developed. The model is employed to study the effect of the temporal resolution of electrical load and PV generation profiles on the rate of self-consumption and the optimal sizing of PV and PV-battery systems. In contrast to previous studies high resolution (10 s) measured input data for both PV generation and electrical load profiles is used for the analysis. The data was obtained by smart meter measurements in 25 different households in Germany. It is shown that the temporal resolution of load profiles is more critical for the accuracy of the determination of self-consumption rates than the resolution of the PV generation. For PV-systems without additional storage accurate results can be obtained by using 15 min solar irradiation data. The required accuracy for the electrical load profiles depends strongly on the load profile characteristics. While good results can be obtained with 60 s for all electrical load profiles, 15 min data can still be sufficient for load profiles that do not exhibit most of their electricity consumption at power levels above 2 k

  6. Design procedures of hybrid PV/SMES system

    International Nuclear Information System (INIS)

    Hamad, Ismail; El-Sayas, M. A.

    2006-01-01

    This paper presents accurate procedures to determine the design parameters of an autonomous hybrid PV/SMES system. Integrating Superconductive magnetic energy storage as a recent storage technology with photovoltaic power system enhances the PV output utilization during the solar radiation fluctuations period. this is because of SMES fast response to any PV output fluctuation. The load demand is supplied either from PV plant or through SMES or from both. Imposed to the technical and economical constrains, the optimum solar cells area and the proper capacity and rating of SMES system are assessed. Regarding solar radiation profile, clear and cloudy days are accurately considered for investigation. Three indices are suggested to express the cloudy and fluctuations conditions. These indices represent the non-utilized PV energy due to clouds (x), fluctuation period (T f ) and location of fluctuations period(t s t). The incremental changes in the design parameters are computed for any variation in these indices. Differentiation between the role of BS and SMES in affecting the results is determined and quantitatively analyzed. The results of clear day condition with SMES are the bas quantities for these changes. Complete analysis of the most effective parameters is presented. Eventually, mathematical models are deduced for each parameter which assists in predicting its behavior against the independent variable.(Author)

  7. Bacillus methylotrophicus Strain NKG-1, Isolated from Changbai Mountain, China, Has Potential Applications as a Biofertilizer or Biocontrol Agent.

    Directory of Open Access Journals (Sweden)

    Beibei Ge

    Full Text Available Chemical pesticides are widely used in agriculture, which endangers both environmental health and food safety. Biocontrol is an environmentally-friendly and cost-effective green technique in environmental protection and agricultural production; it generally uses selected bioresources, including beneficial microorganisms. We isolated a novel bacterial strain (NKG-1 from the rare dormant volcanic soils of Changbai Mountain in China's Jilin Province. The strain was identified as Bacillus methylotrophicus using morphological, biochemical, physiological, and phylogenetic 16S rDNA sequencing data. This strain was able to suppress mycelial growth and conidial germination of numerous plant pathogenic fungi on solid media. A greenhouse experiment showed that application of NKG-1 fermentation broth prior to inoculation of Botrytis cinerea, the cause of gray tomato mold, inhibited growth of the mold by 60%. Furthermore, application of a 100× dilution of NKG-1 fermentation broth to tomato seedlings yielded a significant increase in seedling fresh weight (27.4%, seedling length (12.5%, and root length (57.7% compared to the control. When the same dosage was applied in the field, we observed increases in tomato plant height (14.7%, stem diameter (12.7%, crown width (16.3%, and maximum fruit diameter (11.5%. These results suggest that NKG-1 has potential commercial application as a biofertilizer or biocontrol agent.

  8. A novel synthetic quantification standard including virus and internal report targets: application for the detection and quantification of emerging begomoviruses on tomato.

    Science.gov (United States)

    Péréfarres, Frédéric; Hoareau, Murielle; Chiroleu, Frédéric; Reynaud, Bernard; Dintinger, Jacques; Lett, Jean-Michel

    2011-08-05

    Begomovirus is a genus of phytopathogenic single-stranded DNA viruses, transmitted by the whitefly Bemisia tabaci. This genus includes emerging and economically significant viruses such as those associated with Tomato Yellow Leaf Curl Disease, for which diagnostic tools are needed to prevent dispersion and new introductions. Five real-time PCRs with an internal tomato reporter gene were developed for accurate detection and quantification of monopartite begomoviruses, including two strains of the Tomato yellow leaf curl virus (TYLCV; Mld and IL strains), the Tomato leaf curl Comoros virus-like viruses (ToLCKMV-like viruses) and the two molecules of the bipartite Potato yellow mosaic virus. These diagnostic tools have a unique standard quantification, comprising the targeted viral and internal report amplicons. These duplex real-time PCRs were applied to artificially inoculated plants to monitor and compare their viral development. Real-time PCRs were optimized for accurate detection and quantification over a range of 2 × 10(9) to 2 × 10(3) copies of genomic viral DNA/μL for TYLCV-Mld, TYLCV-IL and PYMV-B and 2 × 10(8) to 2 × 10(3) copies of genomic viral DNA/μL for PYMV-A and ToLCKMV-like viruses. These real-time PCRs were applied to artificially inoculated plants and viral loads were compared at 10, 20 and 30 days post-inoculation. Different patterns of viral accumulation were observed between the bipartite and the monopartite begomoviruses. Interestingly, PYMV accumulated more viral DNA at each date for both genomic components compared to all the monopartite viruses. Also, PYMV reached its highest viral load at 10 dpi contrary to the other viruses (20 dpi). The accumulation kinetics of the two strains of emergent TYLCV differed from the ToLCKMV-like viruses in the higher quantities of viral DNA produced in the early phase of the infection and in the shorter time to reach this peak viral load. To detect and quantify a wide range of begomoviruses, five duplex

  9. A novel synthetic quantification standard including virus and internal report targets: application for the detection and quantification of emerging begomoviruses on tomato

    Directory of Open Access Journals (Sweden)

    Lett Jean-Michel

    2011-08-01

    Full Text Available Abstract Background Begomovirus is a genus of phytopathogenic single-stranded DNA viruses, transmitted by the whitefly Bemisia tabaci. This genus includes emerging and economically significant viruses such as those associated with Tomato Yellow Leaf Curl Disease, for which diagnostic tools are needed to prevent dispersion and new introductions. Five real-time PCRs with an internal tomato reporter gene were developed for accurate detection and quantification of monopartite begomoviruses, including two strains of the Tomato yellow leaf curl virus (TYLCV; Mld and IL strains, the Tomato leaf curl Comoros virus-like viruses (ToLCKMV-like viruses and the two molecules of the bipartite Potato yellow mosaic virus. These diagnostic tools have a unique standard quantification, comprising the targeted viral and internal report amplicons. These duplex real-time PCRs were applied to artificially inoculated plants to monitor and compare their viral development. Results Real-time PCRs were optimized for accurate detection and quantification over a range of 2 × 109 to 2 × 103 copies of genomic viral DNA/μL for TYLCV-Mld, TYLCV-IL and PYMV-B and 2 × 108 to 2 × 103 copies of genomic viral DNA/μL for PYMV-A and ToLCKMV-like viruses. These real-time PCRs were applied to artificially inoculated plants and viral loads were compared at 10, 20 and 30 days post-inoculation. Different patterns of viral accumulation were observed between the bipartite and the monopartite begomoviruses. Interestingly, PYMV accumulated more viral DNA at each date for both genomic components compared to all the monopartite viruses. Also, PYMV reached its highest viral load at 10 dpi contrary to the other viruses (20 dpi. The accumulation kinetics of the two strains of emergent TYLCV differed from the ToLCKMV-like viruses in the higher quantities of viral DNA produced in the early phase of the infection and in the shorter time to reach this peak viral load. Conclusions To detect and

  10. LICOPENE AND Β-CAROTENE IN TOMATO

    Directory of Open Access Journals (Sweden)

    I. Yu. Kondratieva

    2016-01-01

    Full Text Available The high antioxidant activity in tomato fruits is caused not only by sufficient content of vitamin C and polyphenols but also the carotenoids and the fat soluble antioxidants. Lycopene and beta-carotene are the main fat-soluble antioxidants, the consumption of which influences positively on human’s health. It is known that tomato fruits are the source of lycopene for human diet, providing up to 85% of the total lycopene in food. The breeding program for tomato cultivars with high content of carotenoids is a very important task for breeders. In our study the content of betacarotene and lycopene was assessed in 18 tomato accessions with red, pink, yellow and orange fruits obtained in Solanaceae Breeding Laboratory at VNIISSOK. All plants were grown in experimental open field in Odintsovo region, Moscow oblast, VNIISSOK. It was revealed that the typical concentration ratio of lycopene to beta-carotene for pink and red fruits was 1.5 to 10.25, but for yellow and orange fruits was 0 to 0.63. Highest ratio was observed in red fruits in line 230-16. The highest lycopene content was found in red fruits of tree type tomato lines 198-16 and 86F1 (11.5 and 8.7 g/100g. respectively. The highest content of betacarotene was in yellow fruits of line 53-16 F1 (4.1 mg/100g and orange fruits of line 184-16 (6.2 mg/100g. All studied accessions with orange fruits had the higher content of beta-carotene than in standard and highest content of lycopene in this group of accessions. Thus, these fruits had the high nutritional value. The balanced content of lycopene and beta-carotene and low acidity in pink and yellow-orange tomato fruits makes these cultivars the most valuable for children’s diet and people with problems of digestive system.

  11. The Value of Transparency in Distributed Solar PV Markets | Solar Research

    Science.gov (United States)

    suggest that PV customers benefit from gaining access to more PV quotes. Context Prospective PV customers are relatively non-transparent; customers are largely unaware of market prices and may not obtain the lowest available price. PV customers that use quote aggregators-third-party companies that collect quotes

  12. Biochemical evaluation of tomato germplasm part I: workflow and methods

    Science.gov (United States)

    Of the seed crop species conserved at PGRU, tomato (Solanum lycopersicum L.) is the largest in terms of numbers of accessions. Furthermore, tomato ranks very high among vegetable crops in economic importance to the US. We are characterizing a tomato core collection for traits that are of interest to...

  13. On the Impact of Partial Shading on PV Output Power

    DEFF Research Database (Denmark)

    Sera, Dezso; Baghzouz, Yahia

    2008-01-01

    clarifies the mechanism of partial PV shading on a number of PV cells connected in series and/or parallel with and without bypass diodes. The analysis is presented in simple terms and can be useful to someone who wishes to determine the impact of some shading geometry on a PV system. The analysis...... is illustrated by measurements on a commercial 70 W panel, and a 14.4 kW PV array....

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

    Science.gov (United States)

    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.

  15. Review of PV Inverter Technology Cost and Performance Projections

    Energy Technology Data Exchange (ETDEWEB)

    Navigant Consulting Inc.

    2006-01-01

    The National Renewable Energy Laboratory (NREL) has a major responsibility in the implementation of the U.S. Department of Energy's (DOE's) Solar Energy Technologies Program. Sandia National Laboratories (SNL) has a major role in supporting inverter development, characterization, standards, certifications, and verifications. The Solar Energy Technologies Program recently published a Multiyear Technical Plan, which establishes a goal of reducing the Levelized Energy Cost (LEC) for photovoltaic (PV) systems to $0.06/kWh by 2020. The Multiyear Technical Plan estimates that, in order to meet the PV system goal, PV inverter prices will need to decline to $0.25-0.30 Wp by 2020. DOE determined the need to conduct a rigorous review of the PV Program's technical and economic targets, including the target set for PV inverters. NREL requested that Navigant Consulting Inc.(NCI) conduct a review of historical and projected cost and performance improvements for PV inverters, including identification of critical barriers identified and the approaches government might use to address them.

  16. Solar Photovoltaic (PV) Distributed Generation Systems - Control and Protection

    Science.gov (United States)

    Yi, Zhehan

    This dissertation proposes a comprehensive control, power management, and fault detection strategy for solar photovoltaic (PV) distribution generations. Battery storages are typically employed in PV systems to mitigate the power fluctuation caused by unstable solar irradiance. With AC and DC loads, a PV-battery system can be treated as a hybrid microgrid which contains both DC and AC power resources and buses. In this thesis, a control power and management system (CAPMS) for PV-battery hybrid microgrid is proposed, which provides 1) the DC and AC bus voltage and AC frequency regulating scheme and controllers designed to track set points; 2) a power flow management strategy in the hybrid microgrid to achieve system generation and demand balance in both grid-connected and islanded modes; 3) smooth transition control during grid reconnection by frequency and phase synchronization control between the main grid and microgrid. Due to the increasing demands for PV power, scales of PV systems are getting larger and fault detection in PV arrays becomes challenging. High-impedance faults, low-mismatch faults, and faults occurred in low irradiance conditions tend to be hidden due to low fault currents, particularly, when a PV maximum power point tracking (MPPT) algorithm is in-service. If remain undetected, these faults can considerably lower the output energy of solar systems, damage the panels, and potentially cause fire hazards. In this dissertation, fault detection challenges in PV arrays are analyzed in depth, considering the crossing relations among the characteristics of PV, interactions with MPPT algorithms, and the nature of solar irradiance. Two fault detection schemes are then designed as attempts to address these technical issues, which detect faults inside PV arrays accurately even under challenging circumstances, e.g., faults in low irradiance conditions or high-impedance faults. Taking advantage of multi-resolution signal decomposition (MSD), a powerful signal

  17. Processed tomato products as a source of dietary lycopene: bioavailability and antioxidant properties.

    Science.gov (United States)

    Rao, A Venket

    2004-01-01

    Oxidative stress is one of the major contributors to increased risk of chronic diseases. A diet rich in tomatoes and tomato products containing lycopene, a carotenoid antioxidant, has been found to protect against these chronic diseases by mitigating oxidative damage. The study aim was to evaluate the effects of a long-term tomato-rich diet, consisting of various processed tomato products, on bioavailability and antioxidant properties of lycopene. Seventeen healthy human subjects (ten men, seven non-pregnant women) participated in the study. Following a two-week washout period during which subjects avoided foods containing lycopene, all subjects consumed test tomato products including tomato juice, tomato sauce, tomato paste, ketchup, spaghetti sauce, and ready-to-serve tomato soup providing 30 mg of lycopene a day for four weeks. At the end of treatment, serum lycopene level increased significantly (p reduced significantly (p can increase serum lycopene levels and reduce oxidative stress effectively.

  18. Lifetime Evaluation of PV Inverters considering Panel Degradation Rates and Installation Sites

    DEFF Research Database (Denmark)

    Sangwongwanich, Ariya; Yang, Yongheng; Sera, Dezso

    2017-01-01

    The PV inverter lifetime is affected by the installed sites related to different solar irradiance and ambient temperature profiles. In fact, the installation site also affects the PV panel degradation rate, and thus the long-term power production. Prior-art lifetime analysis in PV inverters has...... not yet investigated the impact of panel degradation. This paper thus evaluates the lifetime of PV inverters considering panel degradation rates and installation sites. Evaluations have been carried out on PV systems installed in Denmark and Arizona. The results reveal that the PV panel degradation rate...... has a considerable impact on the PV inverter lifetime, especially in the hot climate (e.g., Arizona), where the panel degrades at a faster rate. In that case, the PV inverter lifetime estimation can be deviated by 54%, if the impact of PV panel degradation is not taken into account....

  19. Survey of tomato diseases in Cameroon

    Directory of Open Access Journals (Sweden)

    Fontem, DA.

    1993-01-01

    Full Text Available Tomato (Lycopersicon esculentum Mill. is the most widely cultivated field vegetable crop in Cameroon. On-farm surveys were undertaken from November 1988 to October 1991 to identify nursery and field diseases in major tomato producing areas of Cameroon, Damping-off and seedling blights were the main seedling diseases. Of the eleven diseases observed in the field, the most widely distributed and severe on the foliage and fruits were early (Alternaria solani and late (Phytophthora infestans blights. Late blight was the most severe disease in the wet season while early blight was most severe in the dry season. Nine pathogens were associated with various fruit rots. This study indicates the need for an identification of appropriate control methods for early and late blights of tomato in Cameroon.

  20. Evaluation of Pochonia chlamydosporia and Purpureocillium lilacinum for Suppression of Meloidogyne enterolobii on Tomato and Banana.

    Science.gov (United States)

    Silva, Silas D; Carneiro, Regina M D G; Faria, Marcos; Souza, Daniela A; Monnerat, Rose G; Lopes, Rogerio B

    2017-03-01

    Meloidogyne enterolobii is one of the most important root-knot nematode in tropical regions, due to its ability to overcome resistance mechanisms of a number of host plants. The lack of new and safe active ingredients against this nematode has restricted control alternatives for growers. Egg-parasitic fungi have been considered as potential candidates for the development of bionematicides. In tissue culture plates, Pochonia chlamydosporia (var. catenulata and chlamydosporia ) and Purpureocillium lilacinum strains were screened for their ability to infect eggs of the root-knot nematode M. enterolobii on water-agar surfaces. Reduction in the hatching of J2 varied from 13% to 84%, depending on strain. The more efficacious strains reduced hatchability of J2 by 57% to 84% when compared to untreated eggs, but average reductions were only 37% to 55% when the same strains were applied to egg masses. Combinations of fungal isolates (one of each species) did not increase the control efficacy in vitro. In experiments in which 10,000 nematode eggs were inoculated per plant, reductions in the number of eggs after 12 months were seen in three of four treatments in banana plants, reaching 34% for P. chlamydosporia var. catenulata . No significant reductions were seen in tomato plants after 3 mon. In another experiment with tomato plants using either P. chlamydosporia var. catenulata or P. lilacinum , the number of eggs was reduced by 34% and 44%, respectively, when initial infestation level was low (500 nematode eggs per plant), but tested strains were not effective under a moderate infestation level (5,000 eggs per plant). Under all infestation levels tested in this work, gall and egg mass indexes (MI) did not differ from the untreated controls, bringing concerns related to the practical adoption of this control strategy by farmers. In our opinion, if the fungi P . chlamydosporia and P . lilacinum are to be used as biocontrol tools toward M. entorolobii , they should focus on

  1. Optimization of a PV/T (photovoltaic/thermal) active solar still

    International Nuclear Information System (INIS)

    Saeedi, F.; Sarhaddi, F.; Behzadmehr, A.

    2015-01-01

    In this paper, the optimization of a PV/T (photovoltaic/thermal) active solar still is carried out. Analytical expressions for glass cover temperature, basin temperature, brackish water temperature and fresh water productivity are obtained by writing energy balance for different components of PV/T active solar still. The output electrical power of PV/T active solar still is calculated by four-parameter I–V (current–voltage) model. Objective function in present study is the energy efficiency of PV/T active solar still. A computer simulation program has been developed in order to obtain thermal and electrical parameters, respectively. The simulation results of the present study are in fair agreement with the experimental data of previous literatures. Finally, the optimization of PV/T active solar still has been carried out and the optimized value of mass flow rate, number of PV/T collector and the objective function have been obtained. Furthermore, the effect of various operating parameters on energy efficiency have been investigated. - Highlights: • The comprehensive optimization of a PV/T active solar still is carried out. • Present study is based on numerical simulation. • A modified energy efficiency for PV/T active solar still is obtained. • The effect of design and operating parameters is investigated on energy efficiency

  2. Design of direct solar PV driven air conditioner

    KAUST Repository

    Huang, Bin-Juine

    2015-12-05

    © 2015 Elsevier Ltd. Solar air conditioning system directly driven by stand-alone solar PV is studied. The air conditioning system will suffer from loss of power if the solar PV power generation is not high enough. It requires a proper system design to match the power consumption of air conditioning system with a proper PV size. Six solar air conditioners with different sizes of PV panel and air conditioners were built and tested outdoors to experimentally investigate the running probabilities of air conditioning at various solar irradiations. It is shown that the instantaneous operation probability (OPB) and the runtime fraction (RF) of the air conditioner are mainly affected by the design parameter rpL (ratio of maximum PV power to load power). The measured OPB is found to be greater than 0.98 at instantaneous solar irradiation IT > 600 W m-2 if rpL > 1.71 RF approaches 1.0 (the air conditioner is run in 100% with solar power) at daily-total solar radiation higher than 13 MJ m-2 day-1, if rpL > 3.

  3. PV supply chain growing pains

    Energy Technology Data Exchange (ETDEWEB)

    Wilkins, A. [Matrix Energy Inc., Montreal, PQ (Canada)

    2010-11-15

    This article discussed issues involving the supply chain for photovoltaic (PV) equipment that is emerging in Ontario as a result of the Feed-in-Tariff (FIT) program that was launched in late 2009. The rapidly developing PV supply chain may not be taking a sustainable path. The domestic-content requirement is making manufacturers outlay capital to set up manufacturing in Ontario without reliable market data. Only a small number of dealer/installers have any meaningful experience designing and installing grid-tie PV. Until recently, wholesale distributors designed and supplied most grid-tie PV systems in Canada, and solar dealers/installers or electricians or electrical contractors did the installation. Instead of selling directly to dealer/installers, solar manufacturers should develop strong relationships with wholesalers, who have system design experience and product training. This would allow manufacturers to focus on their core strength, reach more customers, and keep lower inventory levels. Wholesale distributors in turn provide dealer/installers with expertise in product and system design, training from a range of manufacturers, marketing and logistics support, and immediate access to inventory. Manufacturers generally lack appropriate accounting, engineering, marketing, and logistics services to deal with a multitude of active accounts, and they are not structured to work with architects and engineers to do complete system design. Partnering with wholesale distributors allows manufacturers to take on the residential and small-scale commercial sectors by building brand awareness and increasing market share and sales across Canada. 2 figs.

  4. PV supply chain growing pains

    International Nuclear Information System (INIS)

    Wilkins, A.

    2010-01-01

    This article discussed issues involving the supply chain for photovoltaic (PV) equipment that is emerging in Ontario as a result of the Feed-in-Tariff (FIT) program that was launched in late 2009. The rapidly developing PV supply chain may not be taking a sustainable path. The domestic-content requirement is making manufacturers outlay capital to set up manufacturing in Ontario without reliable market data. Only a small number of dealer/installers have any meaningful experience designing and installing grid-tie PV. Until recently, wholesale distributors designed and supplied most grid-tie PV systems in Canada, and solar dealers/installers or electricians or electrical contractors did the installation. Instead of selling directly to dealer/installers, solar manufacturers should develop strong relationships with wholesalers, who have system design experience and product training. This would allow manufacturers to focus on their core strength, reach more customers, and keep lower inventory levels. Wholesale distributors in turn provide dealer/installers with expertise in product and system design, training from a range of manufacturers, marketing and logistics support, and immediate access to inventory. Manufacturers generally lack appropriate accounting, engineering, marketing, and logistics services to deal with a multitude of active accounts, and they are not structured to work with architects and engineers to do complete system design. Partnering with wholesale distributors allows manufacturers to take on the residential and small-scale commercial sectors by building brand awareness and increasing market share and sales across Canada. 2 figs.

  5. TARGET MICROFLORA OF A TOMATO C ROPPED SOIL.

    African Journals Online (AJOL)

    The effect of benomyl on the microflora of a tomato cropped soil was investigated. ... both in culture and soil treatments. ... pseudomonads to benomyl in culture .... bacterial pathogens of tomato solanucearum. Indian Pin to 11:01. in vitro.

  6. Yield and Adaptability Evaluation of Newly Introduced Tomato ...

    African Journals Online (AJOL)

    High yield is a major ambition to tomato plant breeders and farmers. The purpose of the ... Tabora Region on the growth and yield of newly introduced tomato varieties. The tested ..... (1985). Evaluation of some American tomatocultivars grown.

  7. Generation of large-scale PV scenarios using aggregated power curves

    DEFF Research Database (Denmark)

    Nuño Martinez, Edgar; Cutululis, Nicolaos Antonio

    2017-01-01

    The contribution of solar photovoltaic (PV) power to the generation is becoming more relevant in modern power system. Therefore, there is a need to model the variability large-scale PV generation accurately. This paper presents a novel methodology to generate regional PV scenarios based...... on aggregated power curves rather than traditional physical PV conversion models. Our approach is based on hourly mesoscale reanalysis irradiation data and power measurements and do not require additional variables such as ambient temperature or wind speed. It was used to simulate the PV generation...... on the German system between 2012 and 2015 showing high levels of correlation with actual measurements (93.02–97.60%) and small deviations from the expected capacity factors (0.02–1.80%). Therefore, we are confident about the ability of the proposed model to accurately generate realistic large-scale PV...

  8. Optimal design of NPC and Active-NPC transformerless PV inverters

    DEFF Research Database (Denmark)

    Saridakis, Stefanos; Koutroulis, Eftichios; Blaabjerg, Frede

    2012-01-01

    Targeting at a cost-effective deployment of grid-connected PhotoVoltaic (PV) systems, this paper presents a new methodology for the optimal design of transformerless PV inverters, which are based on the Neutral Point Clamped (NPC) and the Active-Neutral Point Clamped (ANPC) topologies. The design...... optimization results demonstrate that a different set of optimal values of the PV inverter switching frequency and output filter components are derived for the NPC and ANPC topologies, respectively, as well as for each of the PV inverter installation sites under study. The NPC and ANPC PV inverter structures......, which are derived using the proposed design optimization methodology exhibit lower Levelized Cost Of generated Electricity (LCOE) and manufacturing cost and they are simultaneously capable to inject more energy into the electric grid than the corresponding non-optimized PV inverters. Thus, the proposed...

  9. A Novel Frequency Restoring Strategy of Hydro-PV Hybrid Microgrid

    DEFF Research Database (Denmark)

    Wei, Feng; Kai, Sun; Guan, Yajuan

    2014-01-01

    . The existence of frequency steady-state error and the slow active power/frequency dynamic response are inevitable. Therefore, a novel frequency restoring strategy for the hydro-PV hybrid microgrid based on the improved hierarchical control of PV systems is proposed in this paper. The output active power of PV......The conventional PV systems based on the voltage inverters only inject dispatched power to the utility grid when they work at a grid-connected mode in the hydro-PV hybrid microgrid. Due to the droop method employed for load sharing between generators, as well as the enormous inertia of system...... systems is controlled by an extra frequency restoring controller resided in the tertiary control level. The frequency steady-state error is eliminated through regulating and rebalancing the power flow between the hydropower and the PV system. The proposed strategy has verified through simulations...

  10. Wide-band gap devices in PV systems - opportunities and challenges

    DEFF Research Database (Denmark)

    Sintamarean, Nicolae Cristian; Eni, Emanuel-Petre; Blaabjerg, Frede

    2014-01-01

    have an important role in the cost reduction. To increase the efficiency of PV systems, most of solutions for PV inverters have moved to three-level (3L) structures reaching typical efficiencies of 98% due to low switching losses of 600V Si IGBT or MOSFET and reduced core losses in the filter......The recent developments in wide band-gap devices based GaN and SiC is showing a high impact on the PV-inverter technology, which is strongly influenced by efficiency, power density and cost. Besides the high efficiency of PV inverters, also the mechanical size, the compactness and simple structure......) three-phase PV-inverter topologies in terms of efficiency, thermal loading distribution and costs. Moreover the above mentioned PV-inverters are built and tested in laboratory in order to validate the obtained results....

  11. On the Impacts of PV Array Sizing on the Inverter Reliability and Lifetime

    OpenAIRE

    Sangwongwanich, Ariya; Yang, Yongheng; Sera, Dezso; Blaabjerg, Frede; Zhou, Dao

    2018-01-01

    To enable a more wide scale utilization of PV systems, the cost of PV energy should be comparable to or even lower than other energy sources. Due to the relatively low cost of PV modules, oversizing PV arrays becomes a common approach to reduce the cost of PV energy in practice. By doing so, the total energy yield can be increased under weak solar irradiance conditions. However, oversizing the PV array will increase the loading of PV inverters, which may have undesired influence on the PV inv...

  12. PV Module Reliability Workshop | Photovoltaic Research | NREL

    Science.gov (United States)

    Gok, Cara Fagerholm, David M. Burns, Timothy J. Peshek, Laura S. Bruckman, Roger H. French Backsheet Chen, C. H. Hsueh, W. J. Hsieh Accurately Measuring PV Power Loss Due to Soiling-Michael Gostein and Walters, Stephen Barkaszi Tracking PV Changes: Bridging Between Thin-Film Cells and Modules-Russell

  13. Assessing the need for better forecasting and observability of pv

    DEFF Research Database (Denmark)

    Alet, Pierre-Jean; Efthymiou, Venizelos; Graditi, Giorgio

    2017-01-01

    In its review of the challenges and opportunities associated with massive deployment of solar PV generation, the Grid integration working group of the ETIP PV identified forecasting and observability as critical technologies for the planning and operation of the power system with large PV...... penetration. In this white paper ETIP PV set out to spell out in more details what features are needed from these technologies and what is the state of the art....

  14. An improved Agrobacterium mediated transformation in tomato ...

    African Journals Online (AJOL)

    Bacterial wilt is a devastating disease of tomato crop throughout the world. This disease is very dangerous in hot and humid regions, where it spreads with the irrigation water to whole field within days, which resulted in severe decline in yield. Two varieties of tomato were used for developing bacterial wilt resistance.

  15. Estimation of the nutritive value of tomato pomace for ruminant using ...

    African Journals Online (AJOL)

    Jane

    2011-07-06

    Jul 6, 2011 ... composition and estimation of nutritive value of dried tomato pomace (DTP) using in vitro gas ... of processed products such as tomato juice, paste, puree ..... of feeding ensiled mixed tomato and apple pomace on performance.

  16. Salicylic Acid Is Involved in the Basal Resistance of Tomato Plants to Citrus Exocortis Viroid and Tomato Spotted Wilt Virus.

    Directory of Open Access Journals (Sweden)

    M Pilar López-Gresa

    Full Text Available Tomato plants expressing the NahG transgene, which prevents accumulation of endogenous salicylic acid (SA, were used to study the importance of the SA signalling pathway in basal defence against Citrus Exocortis Viroid (CEVd or Tomato Spotted Wilt Virus (TSWV. The lack of SA accumulation in the CEVd- or TSWV-infected NahG tomato plants led to an early and dramatic disease phenotype, as compared to that observed in the corresponding parental Money Maker. Addition of acibenzolar-S-methyl, a benzothiadiazole (BTH, which activates the systemic acquired resistance pathway downstream of SA signalling, improves resistance of NahG tomato plants to CEVd and TSWV. CEVd and TSWV inoculation induced the accumulation of the hydroxycinnamic amides p-coumaroyltyramine, feruloyltyramine, caffeoylputrescine, and feruloylputrescine, and the defence related proteins PR1 and P23 in NahG plants earlier and with more intensity than in Money Maker plants, indicating that SA is not essential for the induction of these plant defence metabolites and proteins. In addition, NahG plants produced very high levels of ethylene upon CEVd or TSWV infection when compared with infected Money Maker plants, indicating that the absence of SA produced additional effects on other metabolic pathways. This is the first report to show that SA is an important component of basal resistance of tomato plants to both CEVd and TSWV, indicating that SA-dependent defence mechanisms play a key role in limiting the severity of symptoms in CEVd- and TSWV-infected NahG tomato plants.

  17. Genome sequencing reveals a new lineage associated with lablab bean and genetic exchange between Xanthomonas axonopodis pv. phaseoli and Xanthomonas fuscans subsp. fuscans

    Directory of Open Access Journals (Sweden)

    Valente eAritua

    2015-10-01

    Full Text Available Common bacterial blight is a devastating seed-borne disease of common beans that also occurs on other legume species including lablab and Lima beans. We sequenced and analysed the genomes of 26 isolates of Xanthomonas axonopodis pv. phaseoli and X. fuscans subsp. fuscans, the causative agents of this disease, collected over four decades and six continents. This revealed considerable genetic variation within both taxa, encompassing both single-nucleotide variants and differences in gene content, that could be exploited for tracking pathogen spread. The bacterial isolate from Lima bean fell within the previously described Genetic Lineage 1, along with the pathovar type isolate (NCPPB 3035. The isolates from lablab represent a new, previously unknown genetic lineage closely related to strains of X. axonopodis pv. glycines. Finally, we identified more than 100 genes that appear to have been recently acquired by Xanthomonas axonopodis pv. phaseoli from X. fuscans subsp. fuscans.

  18. Sub-synchronous resonance damping using high penetration PV plant

    Science.gov (United States)

    Khayyatzadeh, M.; Kazemzadeh, R.

    2017-02-01

    The growing need to the clean and renewable energy has led to the fast development of transmission voltage-level photovoltaic (PV) plants all over the world. These large scale PV plants are going to be connected to power systems and one of the important subjects that should be investigated is the impact of these plants on the power system stability. Can large scale PV plants help to damp sub-synchronous resonance (SSR) and how? In this paper, this capability of a large scale PV plant is investigated. The IEEE Second Benchmark Model aggregated with a PV plant is utilized as the case study. A Wide Area Measurement System (WAMS) based conventional damping controller is designed and added to the main control loop of PV plant in order to damp the SSR and also investigation of the destructive effect of time delay in remote feedback signal. A new optimization algorithm called teaching-learning-based-optimization (TLBO) algorithm has been used for managing the optimization problems. Fast Furrier Transformer (FFT) analysis and also transient simulations of detailed nonlinear system are considered to investigate the performance of the controller. Robustness of the proposed system has been analyzed by facing the system with disturbances leading to significant changes in generator and power system operating point, fault duration time and PV plant generated power. All the simulations are carried out in MATLAB/SIMULINK environment.

  19. Effect of wind speed on performance of a solar-pv array

    Science.gov (United States)

    Thousands of solar photovoltaic (PV) arrays have been installed over the past few years, but the effect of wind speed on the predicted performance of PV arrays is not usually considered by installers. An increase in wind speed will cool the PV array, and the electrical power of the PV modules will ...

  20. Effect of concentration on the rheology and serum separation of tomato suspensions

    NARCIS (Netherlands)

    Ouden, den F.W.C.; Vliet, van T.

    2002-01-01

    The °Brix value of the tomato concentrate, from which tomato suspensions were prepared, was shown to have a large effect on the resulting apparent viscosity and storage modulus. The apparent viscosity of a tomato suspension prepared from a 30 °Brix tomato concentrate was only 35␘f that of a