Thermal concentration effects of tomato pulp and carotenoids extraction from the residue

The present study evaluated the effect of two thermal concentration systems on bioactive compounds, the sugar content of tomato (Solanum lycopersicum L.) pulp, and the carotenoid bioaccessibility of pulp concentrate. The closed processing system ensured a higher retention of phenolic and carotenoid compounds. The bioaccessibility of lycopene in tomato pulp concentrate was relatively low (0.54 %) but higher than in raw tomato pulp (0.15 %), corroborating other results that have reported the low availability of the compound in these matrices. Carotenoid extraction from tomato residue was also evaluated through both conventional (CE) and ultrasound (UAE) extractions together with the stability of extracts over 30 days. UAE promoted a superior release of lycopene and lutein than conventional extraction. Lycopene showed less stability with a reduction of 18 % in 30 days.

Processing tomato waste as a potential bioactive compounds source: phenolic compounds, antioxidant capacity and bioacessibility studies / Resíduo do processamento do tomate como potencial fonte de compostos bioativos: compostos fenólicos, capacidade antioxidante e bioacessibilidade

A comparative study was perfomed with conventional and ultrasound assisted extraction on tomato processing waste. Ultrasound extraction exhibited slightly higher phenolic and flavonoids content, as well as higher ABTS + radical scavenging capacity (4.63 mg GAE.g-1, 0.96 mg RUE.g-1 and 27.90 µmol TE.g -1 respectively). On both extracts, a high percentage of flavonoids was lost during simulated digestion, resulting on a bioacessibility of approximately 13 %. Extracts presented good stability during storage conditions, which indicates a possible technological application.

Foi realizado um estudo comparativo com a extração convencional e assistida por ultrassom em resíduos do processamento de tomate. A extração ultrassônica exibiu teor de fenólicos e flavonóides ligeiramente maiores, bem como maior capacidade antioxidante ABTS + (4,63 mg AG.g-1, 0,96 mg RUE.g-1 e 27,90 µmol TE.g -1, respectivamente). Em ambos os extratos, uma alta porcentagem de flavonóides foi perdida durante a digestão simulada, resultando em uma bioacessibilidade de aproximadamente 13%. Os extratos apresentaram boa estabilidade durante as condições de armazenamento, o que indica uma possível aplicação tecnológica.

Chemical characterization and in vitro antimicrobial activity of honeybee propolis and Scaptotrigona jujuyensis geopropolis against tomato pathogenic bacteria / Caracterização química e atividade antimicrobiana in vitro de própolis de abelhas e de geoprópolis de Scaptotrigona jujuyensis contra bactérias patogênicas do tomate

The antimicrobial activity of four concentrations of hydroalcoholic extracts from honeybee propolis and Scaptotrigona jujuyensis geopropolis was screened in vitro against five tomato pathogenic bacteria. The agar-well diffusion method was used and the tested bacteria were Clavibacter michiganensis subsp. michiganensis, Xanthomonas gardneri, Xanthomonas vesicatoria, Pseudomonas corrugata, and Pseudomonas mediterranea. The main chemical characteristics of propolis and geopropolis, including the polyphenol profile through HPLC-DAD, were also determined. Geopropolis raw sample presented higher values of moisture (7.78%), waxes (50.79%) and ashes (3.69%) than propolis (4.59%, 31.16% and 2.42% respectively). The total polyphenol content and the dry extract were higher in propolis hydroalcoholic extract (3.83 mg eq galic acid mL-1 and 7.87%, respectively) than in the extract of geopropolis (0.16 mg eq galic acid mL-1 and 0.15%, respectively). Chromatographic analysis confirmed the presence of caffeic acid, quercetin, 1,5,7-trihydroxy-flavanone, apigenin, pinobanksin, chrysin, pinocembrin, and galangin in both extracts. The antimicrobial assay showed significant differences between the hydroalcoholic extract activities, as well as between the sensitivity of the tested bacteria. Propolis hydroalcoholic extract dilutions had an inhibitory effect over four of the five tested bacteria, while geopropolis hydroalcoholic extract dilutions were only effective against C. michiganensis subsp. michiganensis, and to a lesser extent. The sequence of bacteria sensitivity to propolis treatments was: C. michiganensis subsp. michiganensis > X. gardneri > X. vesicatoria > P. corrugata. Pseudomonas mediterranea was not sensitive to any of the hydroalcoholic extracts. The antimicrobial activity of both extracts was dose-dependent where the most concentrated treatments were the most effective (15.0 mg mL−1 of geopropolis and 78.7 mg mL−1 of propolis dry extract, respectively). The polyphenol content and the HPLC-DAD profile of the hydroalcoholic extracts disclosed differences in chemical composition that helped to explain the outcomes of the in vitro assay. These results are a contribution to the characterization of bee bioactive products, specifically to propolis and geopropolis. This study indicates the likelihood of using propolis as a non-conventional strategy to control tomato bacterial diseases.(AU)

A atividade antimicrobiana de quatro concentrações de extratos hidroalcoólicos de própolis de abelha e de geoprópolis de Scaptotrigona jujuyensis foi avaliada in vitro contra cinco bactérias patogênicas do tomate. Foi utilizado o método de difusão em ágar e as bactérias testadas foram Clavibacter michiganensis subsp. michiganensis, Xanthomonas gardneri, Xanthomonas vesicatoria, Pseudomonas corrugata, e Pseudomonas mediterranea. As principais características químicas da própolis e da geoprópolis, incluindo o perfil de polifenóis por meio de HPLC-DAD, foram também determinados. A amostra bruta de geoprópolis apresentou mais altos valores de umidade (7,78%), ceras (50,79%) e cinzas (3,69%) do que a amostra de própolis (4,59%, 31,16% e 2,42%, respectivamente). O conteúdo de fenólicos totais e do extrato seco foi superior no extrato hidroalcoólico de própolis (3,83 mg eq ácido gálico ml-1 e 7,87%, respectivamente) do que no extrato hidroalcoólico de geoprópolis (0,16 mg eq ácido gálico ml-1 e 0,15%, respectivamente). A análise cromatográfica confirmou a presença de ácido cafeico, quercetina, 1,5,7-tri-hidroxi-flavanona, apigenina, pinobaksina, crisina, pinocembrina, e galangina em ambos os extratos. O ensaio antibacteriano mostrou diferenças significativas entre as atividades dos extratos hidroalcoólicos assim como entre a sensibilidade das bactérias testadas. As diluições do extrato hidroalcoólico de própolis tiveram efeito inibitório sobre quatro das cinco bactérias testadas enquanto as diluições do extrato hidroalcoólico de geoprópolis foram eficientes somente contra C. michiganensis subsp. michiganensis e em menor extensão. A sequência de sensibilidade das bactérias aos tratamentos com própolis foi: C. michiganensis subsp. michiganensis > X. gardneri > X. vesicatoria > P. corrugata. Pseudomonas mediterranea não foi sensível a nenhum dos extratos hidroalcoólicos. A atividade antibacteriana de ambos os extratos foi dependente da dose, sendo que os tratamentos com maior concentração foram os mais efetivos (15,0 mg mL-1 de geoprópolis e 78,7 mg mL-1 de própolis, extrato seco, respectivamente). O conteúdo de polifenóis e o perfil HPLC-DAD dos extratos hidroalcoólicos mostraram diferenças na composição química, as quais podem ajudar a explicar os resultados do ensaio in vitro. Estes resultados contribuem para a caracterização de produtos bioativos de abelhas, especificamente própolis e geoprópolis. O presente estudo indica a possibilidade de usar própolis como uma estratégia não-convencional para controlar doenças do tomate causadas por bactérias.(AU)

Artificial neural network for prediction of the area under the disease progress curve of tomato late blight

Artificial neural networks (ANN) are computational models inspired by the neural systems of living beings capable of learning from examples and using them to solve problems such as non-linear prediction, and pattern recognition, in addition to several other applications. In this study, ANN were used to predict the value of the area under the disease progress curve (AUDPC) for the tomato late blight pathosystem. The AUDPC is widely used by epidemiologic studies of polycyclic diseases, especially those regarding quantitative resistance of genotypes. However, a series of six evaluations over time is necessary to obtain the final area value for this pathosystem. This study aimed to investigate the utilization of ANN to construct an AUDPC in the tomato late blight pathosystem, using a reduced number of severity evaluations. For this, four independent experiments were performed giving a total of 1836 plants infected with Phytophthora infestans pathogen. They were assessed every three days, comprised six opportunities and AUDPC calculations were performed by the conventional method. After the ANN were created it was possible to predict the AUDPC with correlations of 0.97 and 0.84 when compared to conventional methods, using 50 % and 67 % of the genotype evaluations, respectively. When using the ANN created in an experiment to predict the AUDPC of the other experiments the average correlation was 0.94, with two evaluations, 0.96, with three evaluations, between the predicted values of the ANN and they were observed in six evaluations. We present in this study a new paradigm for the use of AUDPC information in tomato experiments faced with P. infestans. This new proposed paradigm might be adapted to different pathosystems.

Artificial neural network for prediction of the area under the disease progress curve of tomato late blight

Artificial neural networks (ANN) are computational models inspired by the neural systems of living beings capable of learning from examples and using them to solve problems such as non-linear prediction, and pattern recognition, in addition to several other applications. In this study, ANN were used to predict the value of the area under the disease progress curve (AUDPC) for the tomato late blight pathosystem. The AUDPC is widely used by epidemiologic studies of polycyclic diseases, especially those regarding quantitative resistance of genotypes. However, a series of six evaluations over time is necessary to obtain the final area value for this pathosystem. This study aimed to investigate the utilization of ANN to construct an AUDPC in the tomato late blight pathosystem, using a reduced number of severity evaluations. For this, four independent experiments were performed giving a total of 1836 plants infected with Phytophthora infestans pathogen. They were assessed every three days, comprised six opportunities and AUDPC calculations were performed by the conventional method. After the ANN were created it was possible to predict the AUDPC with correlations of 0.97 and 0.84 when compared to conventional methods, using 50 % and 67 % of the genotype evaluations, respectively. When using the ANN created in an experiment to predict the AUDPC of the other experiments the average correlation was 0.94, with two evaluations, 0.96, with three evaluations, between the predicted values of the ANN and they were observed in six evaluations. We present in this study a new paradigm for the use of AUDPC information in tomato experiments faced with P. infestans. This new proposed paradigm might be adapted to different pathosystems.(AU)

Biological control of bacterial spot of tomato by saprobe fungi from semi-arid areas of northeastern Brazil / Controle biológico da mancha bacteriana do tomateiro usando fungos sapróbios do semiárido nordestino do Brasil

Tomato bacterial spot caused by Xanthomonas spp., is a common disease in tomato fields that causes significant economic losses. Due to the difficulty with control of bacterial spot by conventional methods, new techniques such as biological control and induction of resistance are gaining prominence. This study aimed to select saprobe fungi from semi-arid regions of the Brazilian Northeast for the biological control of bacterial spot of tomato. To select the best isolates to control bacterial spot, a greenhouse experiment was initially conducted. Tomato plants (‘Santa Cruz Kada) were treated with filtrates of 25 saprobe fungi and inoculated three days later with Xanthomonas euvesicatoria. Filtrates of Memnoniella levispora, Periconia hispidula, Zygosporium echinosporum, and Chloridium virescens var. virescens were selected as the most effective. Filtrates and volatile compounds from these four isolates were tested for their antibacterial activity in cultures of X. euvesicatoria and in tomato plants (‘Santa Cruz Kada) inoculated with X. euvesicatoria. In vitro, the addition of nonvolatile fungal metabolites into the culture medium at 5% and 50% (v/v) inhibited bacterial growth by 28.9% and 53.8%, respectively. The volatile compounds produced by C. virescens var. virescens reduced the number of colony-forming units of X. euvesicatoria by 25.9%. In vivo, all treatments reduced from 62.4 to 71.3% the area under bacterial spot progress curve, showing the same control efficacy as the commercial resistance inducer used as a positive control (acibenzolar-S-methyl). Systemicity of the fungal filtrates was confirmed in a separate experiment, where application of the treatments exclusively to the third leaf decreased the severity of the disease on the fourth leaf (except for C. virescens var. virescens)...(AU)

A mancha bacteriana do tomateiro causada por Xanthomonas spp. é uma doença frequente nos campos de cultivo, provocando importantes perdas econômicas. Devido à dificuldade de controle com os métodos tradicionais, novas ferramentas de manejo para esta doença, como o controle biológico e a indução de resistência vêm ganhando destaque. O objetivo desse trabalho foi a seleção de fungos sapróbios do semiárido nordestino brasileiro para o controle biológico da mancha bacteriana do tomateiro. Inicialmente, com o objetivo de selecionar os isolados que apresentassem melhor controle da mancha bacteriana, foi montado um ensaio em casa de vegetação com tomateiros (‘Santa Cruz Kada) tratados com os filtrados de 25 fungos sapróbios e inoculados com a bactéria Xanthomonas euvesicatoria três dias depois. Foram selecionados os isolados de Memnoniella levispora, Periconia hispidula, Zygosporium echinosporum e Chloridium virescens var. virescens. Filtrados e voláteis fúngicos desses quatro isolados foram testados in vitro, para se determinar a sensibilidade da bactéria fitopatogênica, e in vivo em tomateiros (‘Santa Cruz Kada) tratados e inoculados com X. euvesicatoria. A incorporação de metabólitos não voláteis dos fungos no meio de cultura a 5% e 50% (v/v) controlou o crescimento da bactéria em até 28,9% e 53,8%, respectivamente. Os compostos voláteis produzidos por C. virescens var. virescens inibiram até 25,9% das unidades formadoras de colônias. Com relação ao experimento in vivo, todos os tratamentos testados reduziram de 62,4 a 71,3% a área abaixo da curva de progresso da mancha bacteriana, mostrando nível de controle igual ao indutor de resistência comercial utilizado como controle positivo (acibenzolar-S-metílico). A sistemicidade deste controle foi confirmada em outro experimento, onde a aplicação dos tratamentos somente na terceira folha determinou menor severidade da doença na quarta folha (exceto para C. virescens var. virescens)...(AU)

Biological control of bacterial spot of tomato by saprobe fungi from semi-arid areas of northeastern Brazil / Controle biológico da mancha bacteriana do tomateiro usando fungos sapróbios do semiárido nordestino do Brasil

Tomato bacterial spot caused by Xanthomonas spp., is a common disease in tomato fields that causes significant economic losses. Due to the difficulty with control of bacterial spot by conventional methods, new techniques such as biological control and induction of resistance are gaining prominence. This study aimed to select saprobe fungi from semi-arid regions of the Brazilian Northeast for the biological control of bacterial spot of tomato. To select the best isolates to control bacterial spot, a greenhouse experiment was initially conducted. Tomato plants (‘Santa Cruz Kada’) were treated with filtrates of 25 saprobe fungi and inoculated three days later with Xanthomonas euvesicatoria. Filtrates of Memnoniella levispora, Periconia hispidula, Zygosporium echinosporum, and Chloridium virescens var. virescens were selected as the most effective. Filtrates and volatile compounds from these four isolates were tested for their antibacterial activity in cultures of X. euvesicatoria and in tomato plants (‘Santa Cruz Kada’) inoculated with X. euvesicatoria. In vitro, the addition of nonvolatile fungal metabolites into the culture medium at 5% and 50% (v/v) inhibited bacterial growth by 28.9% and 53.8%, respectively. The volatile compounds produced by C. virescens var. virescens reduced the number of colony-forming units of X. euvesicatoria by 25.9%. In vivo, all treatments reduced from 62.4 to 71.3% the area under bacterial spot progress curve, showing the same control efficacy as the commercial resistance inducer used as a positive control (acibenzolar-S-methyl). Systemicity of the fungal filtrates was confirmed in a separate experiment, where application of the treatments exclusively to the third leaf decreased the severity of the disease on the fourth leaf (except for C. virescens var. virescens)...

A mancha bacteriana do tomateiro causada por Xanthomonas spp. é uma doença frequente nos campos de cultivo, provocando importantes perdas econômicas. Devido à dificuldade de controle com os métodos tradicionais, novas ferramentas de manejo para esta doença, como o controle biológico e a indução de resistência vêm ganhando destaque. O objetivo desse trabalho foi a seleção de fungos sapróbios do semiárido nordestino brasileiro para o controle biológico da mancha bacteriana do tomateiro. Inicialmente, com o objetivo de selecionar os isolados que apresentassem melhor controle da mancha bacteriana, foi montado um ensaio em casa de vegetação com tomateiros (‘Santa Cruz Kada’) tratados com os filtrados de 25 fungos sapróbios e inoculados com a bactéria Xanthomonas euvesicatoria três dias depois. Foram selecionados os isolados de Memnoniella levispora, Periconia hispidula, Zygosporium echinosporum e Chloridium virescens var. virescens. Filtrados e voláteis fúngicos desses quatro isolados foram testados in vitro, para se determinar a sensibilidade da bactéria fitopatogênica, e in vivo em tomateiros (‘Santa Cruz Kada’) tratados e inoculados com X. euvesicatoria. A incorporação de metabólitos não voláteis dos fungos no meio de cultura a 5% e 50% (v/v) controlou o crescimento da bactéria em até 28,9% e 53,8%, respectivamente. Os compostos voláteis produzidos por C. virescens var. virescens inibiram até 25,9% das unidades formadoras de colônias. Com relação ao experimento in vivo, todos os tratamentos testados reduziram de 62,4 a 71,3% a área abaixo da curva de progresso da mancha bacteriana, mostrando nível de controle igual ao indutor de resistência comercial utilizado como controle positivo (acibenzolar-S-metílico). A sistemicidade deste controle foi confirmada em outro experimento, onde a aplicação dos tratamentos somente na terceira folha determinou menor severidade da doença na quarta folha (exceto para C. virescens var. virescens)...

Plant proton pumps as markers of biostimulant action

A standard protocol to evaluate the effects of biostimulants on plant physiology is still lacking. The proton pumps present in the vacuolar and plasma membranes are the primary agents responsible for the regulation of the electrochemical gradient that energizes the nutrient uptake system and acid growth mechanism of plant cells. In this study, two of these enzymes were characterized as biochemical markers of biostimulant activity. A simple and fast protocol based on the degree of root acidification using a pH sensitive dye and the Micro-Tom tomato as a plant model is proposed as an efficient methodology to prove the efficacy of biostimulants that are claimed to improve nutrient acquisition and root growth. The results agree with the data from more conventional, expensive and time-consuming proton pump assays. A direct correlation was found between plasmalemma proton-adenosine triphosphatase (H+-ATPase) activation and the amount of rhizosphere acidification observed in the bromocresol gel. Moreover, roots of the diageotropica (dgt) Micro-Tom plants, defective in auxin responses, barely acidify bromocresol purple gel even in the presence of indole-3-acetic acid (IAA, 1 M). The biostimulant TEA (vermicompost water extract, 25 %) enhances proton extrusion by 40 % in wild type (WT) plants, but no effect was induced in dgt plants. These results reinforce the notion that the class of biostimulant known as humic substances stimulates plant proton pumps and promotes root growth by exerting an auxin-like bioactivity and establish the usefulness of an economically and technically feasible assay to certify this kind of biostimulant.

Plant proton pumps as markers of biostimulant action

A standard protocol to evaluate the effects of biostimulants on plant physiology is still lacking. The proton pumps present in the vacuolar and plasma membranes are the primary agents responsible for the regulation of the electrochemical gradient that energizes the nutrient uptake system and acid growth mechanism of plant cells. In this study, two of these enzymes were characterized as biochemical markers of biostimulant activity. A simple and fast protocol based on the degree of root acidification using a pH sensitive dye and the Micro-Tom tomato as a plant model is proposed as an efficient methodology to prove the efficacy of biostimulants that are claimed to improve nutrient acquisition and root growth. The results agree with the data from more conventional, expensive and time-consuming proton pump assays. A direct correlation was found between plasmalemma proton-adenosine triphosphatase (H+-ATPase) activation and the amount of rhizosphere acidification observed in the bromocresol gel. Moreover, roots of the diageotropica (dgt) Micro-Tom plants, defective in auxin responses, barely acidify bromocresol purple gel even in the presence of indole-3-acetic acid (IAA, 1 M). The biostimulant TEA (vermicompost water extract, 25 %) enhances proton extrusion by 40 % in wild type (WT) plants, but no effect was induced in dgt plants. These results reinforce the notion that the class of biostimulant known as humic substances stimulates plant proton pumps and promotes root growth by exerting an auxin-like bioactivity and establish the usefulness of an economically and technically feasible assay to certify this kind of biostimulant.(AU)

Volume application rate adapted to the canopy size in greenhouse tomato crops

The application rate of plant-protection products is indicated as a concentration or amount of product per area. Greenhouse crops grow swiftly, and an application rate based on a fixed amount of product per hectare can result either in large losses and overdoses when the plants are small or to be insufficient when the plants are fully developed. To solve these problems, the application rates of plant-protection products need to be adapted to the plant mass present in the greenhouse when the spray is applied. Two models were developed to estimate the leaf area based on easily measured geometric data of the vegetation in a greenhouse tomato crop. The model based on the PRV (Plant Row Volume) had that best results. The calculation of the volume application rate from the PRV has resulted in a reduction of more than 30 % of the quantity of plant protection product sprayed, without decreasing yield. The PRV of a greenhouse tomato (Lycopersicon esculentum Mill.) is an easily measured parameter that enables the estimation of the leaf area index and the use of application strategies adapted to the changes in the plant canopy, saving major amounts of plant protection product used, compared to the conventional system.

Volume application rate adapted to the canopy size in greenhouse tomato crops

The application rate of plant-protection products is indicated as a concentration or amount of product per area. Greenhouse crops grow swiftly, and an application rate based on a fixed amount of product per hectare can result either in large losses and overdoses when the plants are small or to be insufficient when the plants are fully developed. To solve these problems, the application rates of plant-protection products need to be adapted to the plant mass present in the greenhouse when the spray is applied. Two models were developed to estimate the leaf area based on easily measured geometric data of the vegetation in a greenhouse tomato crop. The model based on the PRV (Plant Row Volume) had that best results. The calculation of the volume application rate from the PRV has resulted in a reduction of more than 30 % of the quantity of plant protection product sprayed, without decreasing yield. The PRV of a greenhouse tomato (Lycopersicon esculentum Mill.) is an easily measured parameter that enables the estimation of the leaf area index and the use of application strategies adapted to the changes in the plant canopy, saving major amounts of plant protection product used, compared to the conventional system.

Ocorrência de insetos em plantas de tomateiro tratadas com preparados em altas diluições / Occurrence of insect incidence on tomato crops treated with high dilution preparations

A cultura do tomateiro apresenta grande suscetibilidade a pragas, que no sistema de produção convencional tem demandado uso intensivo de agrotóxicos. O objetivo deste trabalho foi avaliar o efeito de tratamentos fitossanitários, em altas diluições, na incidência de insetos praga em plantas de tomateiro, sob sistema orgânico de produção. Experimentos foram conduzidos a campo nos ciclos produtivos de 2008/2009 e 2009/2010. Os tratamentos constituíram-se dos preparados Staphysagria, Arsenicum album, Sulphur, Arnica montana, nosódios de Solanum lycopersicum e de Solanum aculeatissimum,nas escalas decimal (DH) e centesimal (CH) dedinamização hahnemaniana. Calda bordalesa, calda cúprica e Bacillus thuringiensis foram incluídos em doses ponderais. Constatou-se a presença de coleópteros desfolhadores e tripes, porém apenas Agathomerus sellatus de forma sistemática. População de A. selatus foi reduzida por Sulphur e Arnica montana na dinamização 12 e 24 DH, respectivamente. Preparados em altas diluições apresentam alto potencial de redução de incidência de insetos e de danos de Agathomerus sellatus em tomateiro.

Tomato crops are very susceptible to pests, which in conventional control measures have required the use of a lot of pesticides. The aim of this work was to evaluate the effect of high dilution preparations on the incidence of insects in the tomato crops under organic production systems. Experiments were carried out under fi eld conditions during 2008/2009 and 2009/2010 crop cycles. The treatment consisted of high dilution preparations of Staphysagria, Arsenicum album, Sulphur, Arnica montana, biotherapic of Solanum lycopersicum and biotherapic of Solanum aculeatissimum. All of them were applied at decimal (DH) and centesimal (CH) hahnemaniann dilution order. Bordeaux mixture, cupric preparation and Bacillus thuringiensis were also included. It was observed that coleoptera insects and thrips were sporadically present but Agathomerus sellatus was regularly found in all treatment. The population of A.sellatus was signifi cantly reduced by Sulphur and Arnica montana, respectively to 12 and 24 DH high dilutions. High dilution preparations have the potential to reduce insect incidence on tomato crops and it can be effective control measure for Agathomerus sellatus.

Ocorrência de insetos em plantas de tomateiro tratadas com preparados em altas diluições / Occurrence of insect incidence on tomato crops treated with high dilution preparations

A cultura do tomateiro apresenta grande suscetibilidade a pragas, que no sistema de produção convencional tem demandado uso intensivo de agrotóxicos. O objetivo deste trabalho foi avaliar o efeito de tratamentos fitossanitários, em altas diluições, na incidência de insetos praga em plantas de tomateiro, sob sistema orgânico de produção. Experimentos foram conduzidos a campo nos ciclos produtivos de 2008/2009 e 2009/2010. Os tratamentos constituíram-se dos preparados Staphysagria, Arsenicum album, Sulphur, Arnica montana, nosódios de Solanum lycopersicum e de Solanum aculeatissimum,nas escalas decimal (DH) e centesimal (CH) dedinamização hahnemaniana. Calda bordalesa, calda cúprica e Bacillus thuringiensis foram incluídos em doses ponderais. Constatou-se a presença de coleópteros desfolhadores e tripes, porém apenas Agathomerus sellatus de forma sistemática. População de A. selatus foi reduzida por Sulphur e Arnica montana na dinamização 12 e 24 DH, respectivamente. Preparados em altas diluições apresentam alto potencial de redução de incidência de insetos e de danos de Agathomerus sellatus em tomateiro.(AU)

Tomato crops are very susceptible to pests, which in conventional control measures have required the use of a lot of pesticides. The aim of this work was to evaluate the effect of high dilution preparations on the incidence of insects in the tomato crops under organic production systems. Experiments were carried out under fi eld conditions during 2008/2009 and 2009/2010 crop cycles. The treatment consisted of high dilution preparations of Staphysagria, Arsenicum album, Sulphur, Arnica montana, biotherapic of Solanum lycopersicum and biotherapic of Solanum aculeatissimum. All of them were applied at decimal (DH) and centesimal (CH) hahnemaniann dilution order. Bordeaux mixture, cupric preparation and Bacillus thuringiensis were also included. It was observed that coleoptera insects and thrips were sporadically present but Agathomerus sellatus was regularly found in all treatment. The population of A.sellatus was signifi cantly reduced by Sulphur and Arnica montana, respectively to 12 and 24 DH high dilutions. High dilution preparations have the potential to reduce insect incidence on tomato crops and it can be effective control measure for Agathomerus sellatus.(AU)

Microbiological quality of organic and conventional tomatoes / Qualidade microbiológica de tomate convencional e orgânico

In view of the need to in form the producers, dealers and consumers about the capability of the vegetables in being a vehicle for microorganisms, they should receive suitable hygienic and sanitary treatment. This paper aimed at evaluating the microbiological quality of organic and conventional tomatoes (Lycopersiconesculentum Mill.) commercialized in Curitiba city, southern Brazil. Eight samples of conventional tomatoes and four samples of organic tomatoes were collected from different sites. The microbiological analyses for detecting Salmonella spp and molds and yeasts were conducted according to the Compendium of Methods for Microbiological Examination of Foods. Total coliforms and Escherichia coli were analyzed by the PetrifilmTM methodology. The data were analyzed by variance analysis and Tukey tests. No Salmonella sp was isolated from 25 g of tomato samples. The total coliform counts ranged up to 1.4x103CFU/g and Escherichia coli up to 2.3x102 CFU/g in conventional tomatoes. Yeasts and molds were foundin conventional tomato samples up to 2.1x10, and up to 1.04 x 1012 CFU/g in organic tomato samples. This study clearly shows that the tomatoes ought to receive suitable hygienic and sanitary treatment before being commercialized. (AU)

Characterization of free nitrogen fixing bacteria of the genus Azotobacter in organic vegetable-grown Colombian soils

With the purpose of isolating and characterizing free nitrogen fixing bacteria (FNFB) of the genus Azotobacter, soil samples were collected randomly from different vegetable organic cultures with neutral pH in different zones of Boyacá-Colombia. Isolations were done in selective free nitrogen Ashby-Sucrose agar obtaining a recovery of 40%. Twenty four isolates were evaluated for colony and cellular morphology, pigment production and metabolic activities. Molecular characterization was carried out using amplified ribosomal DNA restriction analysis (ARDRA). After digestion of 16S rDNA Y1-Y3 PCR products (1487pb) with AluI, HpaII and RsaI endonucleases, a polymorphism of 16% was obtained. Cluster analysis showed three main groups based on DNA fingerprints. Comparison between ribotypes generated by isolates and in silico restriction of 16S rDNA partial sequences with same restriction enzymes was done with Gen Workbench v.2.2.4 software. Nevertheless, Y1-Y2 PCR products were analysed using BLASTn. Isolate C5T from tomato (Lycopersicon esculentum) grown soils presented the same in silico restriction patterns with A. chroococcum (AY353708) and 99% of similarity with the same sequence. Isolate C5CO from cauliflower (Brassica oleracea var. botrytis) grown soils showed black pigmentation in Ashby-Benzoate agar and high similarity (91%) with A. nigricans (AB175651) sequence. In this work we demonstrated the utility of molecular techniques and bioinformatics tools as a support to conventional techniques in characterization of the genus Azotobacter from vegetable-grown soils.

Yield and quality criteria in organically and conventionally grown tomatoes in Turkey

The term 'organically grown food' denotes products that have been produced in accordance with the principles and practices of organic agriculture. The use of alternatives to synthetic fertilizers is an important issue in organic systems. A two-year field experiment to evaluate effects of organic fertilizers on the yield and quality of open field grown tomatoes (Lycopersicon esculentum Mill.) was carried out in Southern Turkey in 2000 and 2001. Combinations of manure, blood flour and micronutrient preparations were used for fertilization, and conventional mineral fertilization was included as the control. Yield did not differ between the fertilization and the Conventional treatments in the first year of the study, but the highest yield was obtained from conventional in the second year. No differences were found between treatments in terms of fruit soluble sugar content or citric acid. The application of organic fertilizers positively affected the micronutritional element content of tomato fruits compared to the conventional treatment. Organic fertilization results in improved yield and fruit quality compared to conventional fertilization. In addition, organic fertilization should be supported in order to facilitate reuse and disposal of organic wastes and to maintain and/or increase soil fertility.

O termo "alimentos cultivados organicamente" denota produtos que tenham sido produzidos em conformidade com os princípios e práticas da agricultura orgânica. O uso de alternativas para fertilizantes sintéticos é uma questão importante em sistemas orgânicos. Um experimento de campo foi conduzido no sul da Turquia em 2000 e 2001 para avaliar os efeitos da adubação orgânica na produtividade e na qualidade de tomates (Lycopersicon esculentum Mill), cultivados em campo aberto. Combinações de esterco, farinha de sangue e preparações de micronutrientes foram utilizados para a fertilização, e adubações minerais convencionais foram incluídas como controle. A produção não diferiu entre a fertilização e os tratamentos convencionais no primeiro ano do estudo, porém uma maior produtividade foi obtida a partir do sistema convencional, no segundo ano. Não foram encontradas diferenças entre os tratamentos em termos de teor de açúcares solúveis ou ácido cítrico em frutos. A aplicação de fertilizantes orgânicos afetou positivamente o conteúdo dos elementos micronutritionais dos frutos do tomateiro em relação ao tratamento convencional. A adubação orgânica resultou em maior produtividade e qualidade dos frutos, quando comparada à adubação convencional, e deve ser apoiada, a fim de facilitar a reutilização e eliminação de resíduos orgânicos bem como para manter e/ou aumentar a fertilidade do solo.

Yield and quality criteria in organically and conventionally grown tomatoes in Turkey

The term 'organically grown food' denotes products that have been produced in accordance with the principles and practices of organic agriculture. The use of alternatives to synthetic fertilizers is an important issue in organic systems. A two-year field experiment to evaluate effects of organic fertilizers on the yield and quality of open field grown tomatoes (Lycopersicon esculentum Mill.) was carried out in Southern Turkey in 2000 and 2001. Combinations of manure, blood flour and micronutrient preparations were used for fertilization, and conventional mineral fertilization was included as the control. Yield did not differ between the fertilization and the Conventional treatments in the first year of the study, but the highest yield was obtained from conventional in the second year. No differences were found between treatments in terms of fruit soluble sugar content or citric acid. The application of organic fertilizers positively affected the micronutritional element content of tomato fruits compared to the conventional treatment. Organic fertilization results in improved yield and fruit quality compared to conventional fertilization. In addition, organic fertilization should be supported in order to facilitate reuse and disposal of organic wastes and to maintain and/or increase soil fertility.

O termo "alimentos cultivados organicamente" denota produtos que tenham sido produzidos em conformidade com os princípios e práticas da agricultura orgânica. O uso de alternativas para fertilizantes sintéticos é uma questão importante em sistemas orgânicos. Um experimento de campo foi conduzido no sul da Turquia em 2000 e 2001 para avaliar os efeitos da adubação orgânica na produtividade e na qualidade de tomates (Lycopersicon esculentum Mill), cultivados em campo aberto. Combinações de esterco, farinha de sangue e preparações de micronutrientes foram utilizados para a fertilização, e adubações minerais convencionais foram incluídas como controle. A produção não diferiu entre a fertilização e os tratamentos convencionais no primeiro ano do estudo, porém uma maior produtividade foi obtida a partir do sistema convencional, no segundo ano. Não foram encontradas diferenças entre os tratamentos em termos de teor de açúcares solúveis ou ácido cítrico em frutos. A aplicação de fertilizantes orgânicos afetou positivamente o conteúdo dos elementos micronutritionais dos frutos do tomateiro em relação ao tratamento convencional. A adubação orgânica resultou em maior produtividade e qualidade dos frutos, quando comparada à adubação convencional, e deve ser apoiada, a fim de facilitar a reutilização e eliminação de resíduos orgânicos bem como para manter e/ou aumentar a fertilidade do solo.

Qualidade microbiológica de tomates de mesa (Lycopersicon esculentum), cultivados pelo sistema convencional e orgânico, comercializados no município de Lavras, MG / Microbiological quality of the tomatoes (Lycopersicon esculentum), grown by organic and conventional system, marketed in Lavras, MG

o tomate é a hortaliça de maior importância econômica do Brasil, sendo comercializada na forma in natura e preparada para consumo imediato. Atualmente, a procura por alimentos frescos, nutritivos e principalmente saudáveis é cada vez maior; fato este, devido à preocupação do consumidor com a qualidade de sua dieta alimentar e prevenção de doenças. Dessa forma, o presente estudo objetivou verificar a qualidade microbiológica do tomate de mesa (Lycopersicon esculentum Mill.) pós-colheita, cultivado nos sistemas orgânico e convencional. Foram adquiridas no comércio local no município de Lavras - MG, oito amostras de tomates, de 250g cada, sendo quatro amostras de cultivo orgânico e quatro amostras de cultivo tradicional. A qualidade microbiológica dos tomates foi avaliada por meio da análise de Salmonella spp., Staphylococcus coagulas e positiva, coliformes totais e fecais. Os resultados obtidos, em relação aos coliformes termotolerantes (fecais), das amostras de tomate convencional e orgânico, demonstraram que todas as amostras do sistema convencional estavam dentro dos padrões permitidos pela ANVISA e 50% das amostras de cultivo orgânico apresentaram-se em desconformidade com a legislação. Não foi detectada a presença de Salmonella sp em nenhuma das amostras analisadas. Na contagem de Staphylococcus coagulase positiva, os dados apresentaram valores superiores aos estabelecidos pelas leis vigentes. Contudo, a adoção de medidas de higiene e sanificação adequadas seriam procedimentos viáveis para redução de problemas de contaminação. (AU)

The tomato is the most economically important vegetable crop in Brazil, being marketed as fresh and prepared for immediate consumption. Currently, the demand for fresh food, especially nutritious and healthy is increasing, a fact due to consumer concern about the quality of your diet and disease prevention. Thus, the present study aimed to verify the microbiological quality of fresh tomato (Lycopersicon esculentum Mill.) Post-harvest, grown in organic and conventional systems. Were bought locally and in Lavras - MG, eight samples of tomatoes, 250g each, four samples of organic cultivation and [our samples of traditional cultivation. The microbiological quality of tomatoes was evaluated through analysis of Salmonella spp., Staphylococcus coagulase positive, total and fecal coliforms. The results obtained with respect to coliforms (faecal) samples of tomato conventional and organic, showed that all the samples of the conventional system were within the limits allowed by ANVISA and 50% of the samples showed organic farming is in disagreement with legislation. We did not detect the presence of Salmonella in any of the samples analyzed. On the count of Staphylococcus coagulase positive, the data showed higher values than those established by applicable law. However; the adoption of appropriate hygiene and sanitization procedures would be feasible to reduce contamination problems. (AU)

Late pest control in determinate tomato cultivars

The usage of insecticidal plants and others insect resistant varieties can be strong allies to the Integrated Pest Management (IPM), being able to reduce the number of insecticides applications and to minimize its effect to the man and the environment.The following control techniques were compared in field conditions, investigating the late pest control of two determinate tomato cultivars: a) Conventional - sprayings of metamidophos, buprofezin, acephate, cipermetrin, abamectin, permetrin, teflubenzuron and lufenuron, applied every three to six days; b) IPM - action threshold of each pest to the spraying of imidacloprid, triflumuron, lufenuron and abamectin; c) IPM - Azadirachta indica (neem) - Action threshold of each pest to the spraying of the nim oil (1.2% of azadirachtin) at a concentration of 0.5%. The IPM and IPM - Neem control techniques were efficient controlling the late pest of the tomato cultivar, not differing from the conventional treatment that presented the lowest levels of infestation. The conventional control technique, IPM and IPM-neem promoted bigger tomato production with increasements of up to 74%. The number of sprayings was reduced up to 77% with the IPM and IPM - neem techniques, when compared to the conventional method. The neem product may be a promising alternative to the late pest control in the tomato field that adjusts to the IPM.

O uso de plantas inseticidas e de variedades pode ser forte aliado ao Manejo Integrado de Pragas (MIP), podendo reduzir o número de aplicações de inseticidas e minimizar seus efeitos ao homem e ao meio ambiente. Em condições de campo, visando o controle de pragas tardias do tomateiro em duas cultivares de crescimento determinado, compararam-se as seguintes táticas de controle: a) Convencional - pulverizações com os produtos metamidofós, buprofezin, acefato, cipermetrina, abamectina, permetrina, teflubenzuron e lufenuron, aplicados em intervalos de três a seis dias; b) MIP - nível de ação de cada praga para aplicações de imidacloprid, triflumuron, lufenuron e abamectina; c) MIP - Azadirachta indica (nim) - nível de ação de cada praga para aplicações de óleo de nim (1,2% de azadiractina) a 0,5%. As táticas de controle MIP e MIP - nim foram eficientes no controle das pragas tardias do tomateiro, quando a pressão da população é baixa, não diferindo do tratamento convencional que apresentou as menores médias de infestação. As táticas de controle convencional, MIP e MIP-nim promoveram maiores produções do tomateiro, com incrementos de até 74%. O número de pulverizações foi reduzido em até 77% com as táticas MIP e MIP - nim, comparado ao método convencional. O produto nim pode ser alternativa promissora no controle de pragas tardias do tomateiro em campo, que se ajusta ao MIP.

Late pest control in determinate tomato cultivars

The usage of insecticidal plants and others insect resistant varieties can be strong allies to the Integrated Pest Management (IPM), being able to reduce the number of insecticides applications and to minimize its effect to the man and the environment.The following control techniques were compared in field conditions, investigating the late pest control of two determinate tomato cultivars: a) Conventional - sprayings of metamidophos, buprofezin, acephate, cipermetrin, abamectin, permetrin, teflubenzuron and lufenuron, applied every three to six days; b) IPM - action threshold of each pest to the spraying of imidacloprid, triflumuron, lufenuron and abamectin; c) IPM - Azadirachta indica (neem) - Action threshold of each pest to the spraying of the nim oil (1.2% of azadirachtin) at a concentration of 0.5%. The IPM and IPM - Neem control techniques were efficient controlling the late pest of the tomato cultivar, not differing from the conventional treatment that presented the lowest levels of infestation. The conventional control technique, IPM and IPM-neem promoted bigger tomato production with increasements of up to 74%. The number of sprayings was reduced up to 77% with the IPM and IPM - neem techniques, when compared to the conventional method. The neem product may be a promising alternative to the late pest control in the tomato field that adjusts to the IPM.

O uso de plantas inseticidas e de variedades pode ser forte aliado ao Manejo Integrado de Pragas (MIP), podendo reduzir o número de aplicações de inseticidas e minimizar seus efeitos ao homem e ao meio ambiente. Em condições de campo, visando o controle de pragas tardias do tomateiro em duas cultivares de crescimento determinado, compararam-se as seguintes táticas de controle: a) Convencional - pulverizações com os produtos metamidofós, buprofezin, acefato, cipermetrina, abamectina, permetrina, teflubenzuron e lufenuron, aplicados em intervalos de três a seis dias; b) MIP - nível de ação de cada praga para aplicações de imidacloprid, triflumuron, lufenuron e abamectina; c) MIP - Azadirachta indica (nim) - nível de ação de cada praga para aplicações de óleo de nim (1,2% de azadiractina) a 0,5%. As táticas de controle MIP e MIP - nim foram eficientes no controle das pragas tardias do tomateiro, quando a pressão da população é baixa, não diferindo do tratamento convencional que apresentou as menores médias de infestação. As táticas de controle convencional, MIP e MIP-nim promoveram maiores produções do tomateiro, com incrementos de até 74%. O número de pulverizações foi reduzido em até 77% com as táticas MIP e MIP - nim, comparado ao método convencional. O produto nim pode ser alternativa promissora no controle de pragas tardias do tomateiro em campo, que se ajusta ao MIP.