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Sample records for alface lactuca sativa

  1. Parasitos em alfaces (Lactuca sativa de mercados e feiras livres de Lages - Santa Catarina = Lettuces (Lactuca sativa parasites in markets and free fairs from Lages - Santa Catarina

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    Quadros, Rosiléia Marinho de

    2008-01-01

    Full Text Available Objetivo: avaliar a contaminação por parasitos de interesse em Saúde Pública em alfaces (Lactuca sativa comercializadas no município de Lages, Santa Catarina. Materiais e Métodos: Foi utilizado um processo de amostragem intencional, selecionando-se oito supermercados e duas feiras, de acordo com a abrangência e volume de vendas desses estabelecimentos para a cidade. Foram processadas 122 amostras de alfaces, pelas técnicas de sedimentação espontânea (Lutz, centrífugo-flutuação em sulfato de zinco (Faust, centrífugo-flutuação em solução de sacarose (Sheather e coloração de Ziehl Neelsen modificada. Resultados: O índice de parasitismo foi de 88,5% (108/122 com 77% (94/122 e 11,5% (14/122 para as amostras de supermercados e de feiras livres, respectivamente. A técnica de Lutz detectou 46,7% (57/122 de alfaces parasitadas; Sheather e Faust evidenciaram 31,1% (38/122 e 10,6% (13/122 de alfaces com ovos e/ou oocistos de parasitos, respectivamente. Predominaram os gêneros Eimeria, Giardia e Entamoeba. Conclusões: As amostras analisadas apresentaram baixos padrões higiênicos, necessitando de vigilância sanitária mais atuante na fiscalização de todas as etapas do processo produtivo de hortaliças

  2. Enteroparasitas em alfaces (Lactuca sativa comercializadas na cidade de Guarapuava (PR / Enteroparasites on commercial lettuce (Lactuca sativa in Guarapuava City, Paraná State

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    Silvia Cristina Osaki

    2010-08-01

    Full Text Available O consumo de hortaliças cruas constitui importante meio de transmissão de enteroparasitoses. O objetivo deste trabalho foi avaliar a contaminação parasitária em alfaces (Lactuca sativa comercializadas na cidade de Guarapuava (PR. No período de julho/2005 a junho/2006, 52 supermercados foram visitados, com colheita de um pé de alface. A análise parasitológica foi realizada após duas lavagens, filtragem em gaze e sedimentação. O sedimento, corado pelo lugol, foi analisado microscopicamente por exame direto e após centrífugo-flutuação em sulfato de zinco. Das 52 amostras de alface avaliadas, 18 (34,6% apresentaram uma ou mais estruturas parasitárias como cistos de Giardia spp. (7,7%, de Entamoeba spp. (11,5% e de Balantidium coli (3,8%, oocistos de coccídios (7,7% e ovos de Capillaria spp. (3,8%. Esse alto número de amostras contaminadas aponta deficiências na cadeia produtiva dessas hortaliças, indicando a necessidade de adequada higienização antes de seu consumo. AbstractThe ingestion of raw vegetables is an important mode of enteroparasites transmission. The aim of this study was to evaluate the parasitological contamination of lettuce (Lactuca sativa commercialized in Guarapuava City, Parana State. Fifty-two samples of lettuce were collected from supermarkets during the period of July 2005 and June 2006. Parasitological analysis was realized by the sedimentation technique. Lugol-stained sediments were microscopically analyzed by direct exam and after centrifugation-fluctuation in zinc sulfate. A total of 18 out of 52 lettuce samples analyzed (34.6% were positive for one or more parasitic structures. The parasites found in the analysis were Giardia spp. (7.7%, Entamoeba spp. (11.5%, Balantidium coli (3.8%, coccidian oocysts (7.7% and Capillaria spp. eggs (3.8%. Such high occurrence of contaminated samples revealed deficiencies in the chain of lettuce cultivation, which suggests a need for improvement in the current

  3. Freqüência de enteroparasitas em amostras de alface (Lactuca sativa comercializadas em Lavras, Minas Gerais Frequency of intestinal parasites in samples of lettuce (Lactuca sativa commercialized in Lavras, Minas Gerais State

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    Antônio Marcos Guimarães

    2003-10-01

    Full Text Available O objetivo deste trabalho foi realizar uma avaliação parasitológica em amostras de alface (Lactuca sativa comercializadas em Lavras, MG. As amostras de alfaces apresentaram baixos padrões higiênicos, indicados pela presença de formas parasitológicas de origem animal ou humana e alta concentração de coliformes fecais.The aim of this study was to evaluate the parasitological contamination in samples of lettuce (Lactuca sativa commercialized in Lavras city, Minas Gerais. The samples of lettuce showed low hygienic conditions, indicated by the presence of parasites of animal or human origin and high concentration of fecal coliforms.

  4. USO DE SUBSTRATOS ALTERNATIVOS PARA A PRODUÇÃO DE MUDAS DE ALFACE (LACTUCA SATIVA L.

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    Emanuele Baifus Manke

    2017-01-01

    Full Text Available O objetivo desse trabalho foi avaliar o efeito de diferentes substratos alternativos na produção de mudas de alface (Lactuca sativa L.. No experimento foram avaliados seis diferentes substratos. As variáveis avaliadas foram: número de folhas, comprimento de raiz, altura da muda, massa fresca de parte aérea, massa seca de parte aérea, massa fresca do sistema radicular e massa seca do sistema radicular. Os tratamentos T2: (75% Casca de Arroz Carbonizada + 25% Composto Orgânico Ecocitrus e T3: (50% Casca de Arroz Carbonizada + 50% Composto Orgânico Ecocitrus permitiram a obtenção de mudas de alface com boas respostas agronômicas, construindo-se uma opção viável na redução do custo para a produção de mudas de alface para a agricultura familiar.

  5. Active packaging for fresh-cut iceberg lettuce (Lactuca sativa L. / Embalagem ativa para alface americana (Lactuca sativa L. minimamente processada

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    Fábio Yamashita

    2010-09-01

    Full Text Available The minimal processing of horticultural products endears the raw material and is convenient to the consumer due to the facility for preparing and consuming. The objective of this work was to develop an active packaging for fresh-cut iceberg lettuce (Lactuca sativa L. to increase its shelf life. Minimally processing methodology was defined and the product quality was determined by sensorial, physico-chemical and microbiological analysis. The lettuce tree was selected, trimmed, pre-washed, soaked in sanitized water (100ppm of active chlorine for 15 minutes and centrifuged. The lettuce leafs were packed in polypropylene pots with a sachet containing 1-methylcyclopropene (1-MCP and sealed with biodegradable starch film. Soon after the processing, the product was stored at 4oC for 12 days. Periodically samples were evaluated in terms of appearance and purchase intention, soluble solids and vitamin C contents, pH, texture, color, weight loss and total count of mesophilic and psicotrofic microorganisms, lactic bacteria, mould and yeast. Using 1-MCP in sachet format did not increase the lettuce shelf life but the minimal processing combined with packaging sealed with biodegradable film is practicable as the product showed good sensorial acceptance, low microbiological counts and shelf life of 5 days at 4oC.O processamento mínimo de produtos hortícolas agrega valor à matéria-prima e são convenientes ao consumidor, devido à facilidade de preparo e consumo. O objetivo do trabalho foi desenvolver uma embalagem ativa para alface americana (Lactuca sativa L. minimamente processada visando o aumento da vida útil. Foi definida uma metodologia de processamento mínimo e a qualidade do produto foi acompanhada através de avaliação sensorial, físico-química e microbiológica. As cabeças de alface foram desfolhadas, selecionadas, pré-lavadas, sanificadas (100 ppm de cloro ativo por 15 minutos e centrifugadas. As folhas foram acondicionadas em potes de

  6. Produção de alface (Lactuca sativa L. sob diferentes doses de vermicomposto

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    M. S. Teodoro

    2016-01-01

    Full Text Available O objetivo deste trabalho foi avaliar o efeito de diferentes dosagens de vermicomposto sobre a produção de alface, cultivar Baba de Verão. O ensaio foi conduzido em Latossolo Amarelo Distrófico de textura média fase caatinga litorânea, na Embrapa Meio-Norte, UEP – Parnaíba, de setembro a outubro de 2013. O delineamento experimental adotado foi o de blocos casualizados, com cinco tratamentos e quatro repetições.  Os tratamentos constituíram-se das dosagens de vermicomposto aplicadas na adubação das covas: 0 g/cova; 62,5 g/cova; 125 g/cova; 187,5 g/cova e 250 g/cova. As características avaliadas foram: Diâmetro da base (DB; Número de folhas (NF; Massa fresca da parte aérea (MFPA; Massa fresca da raiz (MFR; Massa seca da parte aérea (MSPA e Massa seca da raiz (MSR. Para todas as características avaliadas o vermicomposto de minhoca apresentou resultados aceitáveis, não havendo diferenças significativas para a maioria das características agronômicas estudadas. Os maiores pesos médios foram obtidos com a dosagem de 187,5 g/cova (40 t/ha. A biomassa fresca e seca da alface obtida nesta dosagem foram superiores em aproximadamente 50 e 49%, respectivamente, em relação à testemunha. O mesmo observa-se para a massa fresca e seca das raízes (25 e 24%, respectivamente, apesar de não diferirem estatisticamente entre os demais tratamentos. Apesar dos problemas relacionados ao pendoamento, a utilização do vermicomposto, permitiu a obtenção de alface, demonstrando que a adubação de plantio com este insumo orgânico pode ser considerada uma prática promissora na produção dessa hortaliça em sistemas orgânicos na região. Entretanto, é importante se adequar a época de cultivo, ou então, trabalhar com cultivares adaptadas para as condições edafoclimáticas da região.  Production of lettuce (Lactuca sativa L. under different doses of worm compostAbstract: Different dosages of fertilization on the production of

  7. Efeito do cultivo orgânico e convencional sobre a vida-de-prateleira de alface americana (Lactuca sativa L. minimamente processada

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    Mello Júlio César

    2003-01-01

    Full Text Available A alface americana (Lactuca sativa, minimamente processada, foi avaliada quanto aos efeitos dos diferentes sistemas de cultivo (orgânico e convencional, sobre a vida-de-prateleira. A alface minimamente processada foi embalada em sacos de polietileno de baixa densidade (PEBD, armazenada em refrigerador a 4masculineC e avaliada até o final da vida-de-prateleira, estabelecida por métodos sensoriais. As avaliações foram realizadas durante a estocagem, nas condições pré-estabelecidas. Nos tempos zero a dez dias, uma equipe sensorial treinada avaliou a alface quanto a: cor, brilho, escurecimento enzimático, aroma, odor estranho, textura e sabor (escores de zero a dez. O teste sensorial determinou que o escore seis (6 eliminaria a amostra; a alface orgânica, atingiu o escore mínimo em tempo superior ao da alface convencional, tendo sido sensivelmente superior a esta em todos os atributos testados.

  8. Qualidade física, microbiológica e parasitológica de alfaces (Lactuca sativa de diferentes sistemas de cultivo Physical, microbiological and parasitological quality of lettuce (Lactuca sativa from different growing processes

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    Ligia Regina R. de Santana

    2006-06-01

    Full Text Available A alface (Lactuca sativa é a hortaliça folhosa mais comercializada no Brasil. Seu baixo valor calórico a qualifica para diversas dietas, o que favorece o seu consumo sob a forma crua, possibilitando a ocorrência de enfermidades intestinais. O objetivo deste trabalho foi realizar uma avaliação física, microbiológica e parasitológica de amostras de alfaces, variedade crespa, provenientes dos sistemas de cultivo orgânico, tradicional e hidropônico, comercializadas nos principais supermercados da cidade de Salvador (BA, no período de setembro de 2003 a junho de 2004. As amostras do cultivo hidropônico apresentaram o menor peso total e da parte bio-comestível, diferindo significativamente (pThe lettuce (Lactuca sativa has economic importance to the people in Brazil. The aim of this study was to carry out a physical, microbiological and parasitological evaluations in the lettuce samples - crisp variety, according to organic, traditional and hydroponics growing processes, commercialized at the supermarkets of the City of Salvador, Bahia, Brazil, collected from September/2003 until June/2004. The hydroponics lettuce samples showed the lowest total and edible part weight; they were inserted into Extra rate quality standard, according to the current legislation, whereas the organic and traditional lettuce samples were inserted into First and Second rate quality standard, respectively. The lettuce samples, independently of the growing process, showed low hygienic conditions, indicated by the presence of parasites of animal or human origin, and high concentration of fecal coliforms; the organic lettuce samples showed the highest frequencies of enteroparasities and fecal coliforms concentration, followed by the traditional and hydroponics lettuce samples. Considering the obtained results, the importance of this kind of food in the transmission of enteroparasities is stressed, as well as the need of actions which improve the sanitary conditions

  9. Avaliação do efeito da peletização sobre o vigor de sementes de alface (Lactuca sativa L. Evaluation of the pelletization effect on lettuce seed vigor (Lactuca sativa L.

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    H.M. Coraspe

    1993-12-01

    Full Text Available Sementes de alface (Lactuca sativa L. cv. Verônica, do tipo crespo, foram submetidas a testes de umidade, germinação, velocidade de germinação, envelhecimento acelerado, teste de frio, condutividade elétrica, e emergência. Os testes de laboratório não evidenciaram diferenças significativas da qualidade fisiológica entre sementes peletizadas e sem paletes, exceto o teste de envelhecimento acelerado. As correlações entre os testes de laboratório e a emergência em campo não foram significativas. A emergência em campo foi significativamente maior nas sementes peletizadas.Seeds of "Veronica", a crisphead lettuce cultivar (Lactuca sativa L., were submitted to laboratory tests of humidity, germination, velocity of germination, accelerated aging, cold, electrical conductivity and field emergence. Tests did not show any significant difference of the physiological quality between bare and pelleted seeds, except the accelerated aging. Correlations among laboratory tests and the field emergence were not significant. The field emergence was significantly higher from pelleted seeds than seeds without pellets.

  10. Emergência e crescimento de alface (Lactuca sativa L. submetida a substratos orgânicos

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    Franciele Mara Lucca Zanardo Bohm

    2017-06-01

    Full Text Available A agricultura orgânica se destaca como modo de produção que consiste em um sistema sustentável. Um dos desafios desse método de cultivo é a produção de alimentos com qualidade em quantidades suficientes sem comprometer o meio ambiente. Objetivou-se analisar o efeito de substratos orgânicos na germinação e crescimento inicial de alface. O experimento foi conduzido em delineamento inteiramente casualizado com quatro tratamentos (substratos e duas repetições. Foram testados os substratos: composto de Sibipiruna, substrato comercial, composto de Sibipiruna com chorume e substrato comercial com chorume. O chorume foi obtido exclusivamente da decomposição de vegetais. Foi avaliado o efeito dos substratos pelo percentual de germinação, massa fresca, massa seca e comprimento da radícula. Pôde-se considerar que houve diferença significativa entre os tratamentos. As sementes, quando germinadas em substrato de Sibipiruna com chorume, apresentaram maior massa seca e comprimento de radícula. Com relação à massa fresca, os valores obtidos foram maiores quando o chorume foi adicionado a ambos os substratos. O chorume obtido da decomposição de vegetais aumentou a germinação e o crescimento inicial das plântulas.Emergence and growth of lettuce (Lactuca sativa L. submitted to organic substratesAbstract: Organic agriculture stands out as a mode of production consisting of a sustainable system. One of the challenges of this method of cultivation is the production of sufficient quality food in sufficient quantities without compromising the environment. The objective of this study was to analyze the effect of organic substrates on germination and initial lettuce growth. The experiment was conducted in a completely randomized design with four treatments (substrates and two replicates. The substrates were tested: Sibipiruna compound, commercial substrate, Sibipiruna compound with slurry and commercial slurry substrate. The manure was

  11. PERIGOS ASSOCIADOS AO CONSUMO DA ALFACE, (Lactuca sativa, IN NATURA

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    A. D. I. MOGHARBEL

    2008-09-01

    Full Text Available

    A prevenção de riscos de contaminação por agentes patogênicos em folhas de alface passa pelas boas práticas agrícolas que vai desde a semeadura até a colheita além de outros importantes aspectos, ainda no processo do cultivar, como qualidade da água usada para irrigação, emprego de práticas sanitárias adequadas pelos produtores na manipulação das plantas e higiene do agricultor no campo. Manter a segurança de contaminação bacteriana de frutas e de vegetais frescos requer um conhecimento de sistemas que abranja todos os aspectos da produção, do processamento, da distribuição e do uso. A orientação aos consumidores quanto aos cuidados no armazenamento e na manipulação apropriados do produto fresco, deve ser incentivada pelas autoridades sanitárias, como forma de se evitar doenças veiculadas pelos alimentos. Desta forma, a proteção de contaminantes patológicos em vegetais frescos, visando a proteção tanto do produtor como do consumidor, vão de encontro a algumas práticas similares do sistema APPCC, onde se projetam atributos de limitação, controle, e monitoramento das fontes de contato na produção dos vegetais.

  12. Produção de alface (Lactuca sativa L., em função de diferentes concentrações e tipos de biofertilizantes

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    Thiago Pereira de Sousa

    2014-12-01

    Full Text Available Normal 0 21 false false false PT-BR X-NONE X-NONE A alface (Lactuca sativa L. originou-se de espécies silvestres, ainda atualmente encontradas em regiões de clima temperado, no sul da Europa e na Ásia Ocidental. Objetivou-se com este trabalho, estudar o efeito de diferentes concentrações de urina de vaca e biofertilizante aplicados via foliar na cultura da alface em condições edafoclimáticas do município de Catolé do Rocha-PB. O experimento foi conduzido em condições de campo na estação experimental agroecológica do Campus IV da UEPB. O delineamento experimental utilizado foi em blocos casualisados com 12 tratamentos, no esquema fatorial 6x2, com 4 repetições. Testou-se 06 concentrações de biofertilizante: (C1= 0,0; C2= 10; C3= 20; C4= 30; C5= 40 e C6= 50 m/L planta/vez, respectivamente e aplicação do biofertilizante (T1 e da urina de vaca (T2, na produção da alface. Utilizou-se sementes da cultivar Elba (grupo crespo. Avaliou-se: número de folhas (NF, peso verde da folha (PVF e peso verde da parte aérea (PVPA. As concentrações de biofertilizante se comportaram de maneira semelhante dentro dos tipos de biofertilizante e vice-versa. As plantas de alface Elba submetidas á concentração C3= 20 ml/L planta/vez, na presença de urina de vaca (T2 proporcionaram maiores taxas de desenvolvimento foliar.

  13. Lactuca sativa L.

    African Journals Online (AJOL)

    Jane

    2011-10-24

    Oct 24, 2011 ... Seeds of four lettuce (Lactuca sativa L.) genotypes viz., Great Lakes (GL), Paris Island cos, Kagraner. Sommer (KS) and Isadora were assessed for their response to salt at the germination and seedling stages. The germination rate of the four varieties was comparatively studied under 0, 50, 100, 150 and.

  14. EFEITO DE DIFERENTES RESÍDUOS ORGÂNICOS NO DESENVOLVIMENTO E NA PRODUTIVIDADE DA ALFACE (Lactuca sativa L. EFFECT OF DIFFERENT ORGANIC RESIDUES IN THE DEVELOPMENT AND IN THE PRODUCTIVITY OF LETTUCE (Lactuca sativa L

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    José Xavier de Almeida Neto

    2007-09-01

    Full Text Available

    O presente trabalho teve o objetivo de verificar o efeito das adubações orgânica e química e a mistura das mesmas, e também avaliar o comportamento dos estercos de galinhas e de bovinos no desenvolvimento e na produtividade da alface (Lactuca sativa L.. O experimento foi conduzido na Escola de Agronomia da Universidade Federal de Goiás, em LE., usando a cultivar Regina (Vigoragro. O delineamento foi inteiramente casualizado, constando de sete tratamentos: 1 testemunha (sem adubação; 2 adubação química + esterco bovino; 3 adubação química, sem adubação orgânica; 4 esterco de galinhas (dobro da dose recomendada, sem adubação química; 5 esterco bovino (dobro da dose, sem adubação química; 6 adubação química + esterco de galinhas; 7 adubação química (dobro da dose, tendo-se empregado as quantidades segundo as recomendações da C.F.S., para Goiás (1988. Os resultados obtidos mostraram que os tratamentos 2, 5 e 6 foram significativamente iguais entre si e superiores aos demais, em todas as variáveis analisadas (peso, diâmetro e valor comercial.

    The present study was done to verify the effect of organic and chemical fertilizations either together or separated, on the productivity of lettuce (Lactuca sativa L. The influence of chicken and cattle manure on the lettuce productivity was also verified. The field experiment was conducted at the Escola de Agronomia, U.F.G., Goiânia, Goiás (Brazil, in dark red latosol (oxisol, using the cultivar ‘Reqina’ (seeds from Vigoragro. The experimental design was completely randomized, with seven treatments, as follow: 1 testimony (without fertilization; 2 chemical fertilization + cattle manure; 3 chemical fertilization, without manure fertilization; 4 chicken manure (double of the recommended level, without chemical fertilization; 5

  15. Lettuce (Lactuca sativa L. seedling production with different sources of phosphate and phosphate solubilizing microorganisms / Produção de mudas de alface (Lactuca sativa L. em presença de diferentes fontes fosfatadas e microrganismos

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    Germano Nunes Silva Filho

    2009-10-01

    Full Text Available The objective of this work was to evaluate the behaviour of phosphate solubilizing microorganisms (fungus: 310A, 061, 062 e 251, bacterias 163, 160 e 161 in promoting nutrition and growth of lettuce(Lactuca sativa L. seedlings cultivated in trays with sterilized substrate fertilized and phosphates source. A randomized completely design was used, with a factorial 4x8 scheme (four treatments with phosphate nutrition and inoculated with eight phosphate solubilizing microorganisms and four replications. Each replication was made of 10 cells. The experiment was evaluated 35 days after planting for dry matter, P percentage and total phosphorus of above ground parts. The triple super phosphate (SFT had better results than the others, including the control treatment, in all analyzed parameters. On the dry matter production, it was observed negative effect from inoculation in five treatments fertilized with SFT. There was no effect of isolates on the phosphorus content values. In the values of total phosphorus, the isolates 061, 062 e 163 increased the parameter values on the fertilized treatment with SFT. The natural phosphates presented low efficiency when compared to dissolvable fertilizer on the availability of phosphorus to the plants.O objetivo deste trabalho foi avaliar o comportamento de microrganismos solubilizadores de fosfatos (fungos: 310A, 061, 062 e 251; bactérias: 163, 160 e 161 na promoção da nutrição e crescimento de mudas de alface (Lactuca sativa L., cultivadas em bandejas com substrato esterilizado e adubadas com fontes fosfatadas. Foi utilizado um delineamento inteiramente casualizado, arranjo fatorial 4 x 8 (quatro tratamentos de adubação fosfatada e oito tratamentos de inoculação microrganismos solubilizadores de fosfatos com quatro repetições por isolado. Cada repetição foi constituída de 10 células. Aos 35 dias de cultivo, as plantas foram colhidas avaliando-se a matéria seca, porcentagem de P e P total da parte a

  16. Crescimento de plântulas de alface (Lactuca sativa L. em solo oriundo de um povoamento de Luetzelburgia auriculata (Allemão Ducke

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    Érika do Nascimento Fernandes Pinto

    2016-04-01

    Full Text Available Esta pesquisa buscou conhecer características alelopáticas e de fertilidade de um solo oriundo de povoamento de Luetzelburgia auriculata (Allemão Ducke, através da avaliação do crescimento de plantas de alface. Inicialmente, realizou-se a coleta do solo sob o povoamento da L. auriculata (SPL e de uma área externa a esse povoamento (SAE, na Fazenda Cachoeira de São Porfírio, em Várzea-PB, e encaminhou-se para o Centro de Saúde e Tecnologia Rural da Universidade Federal de Campina Grande, Campus de Patos. Em delineamento inteiramente casualizado, aplicaram-se cinco tratamentos com cinco repetições, colocando-se três sementes de alface por vaso contendo os seguintes tratamentos: T1=100%SAE; T2=100%SPL; T3=75%SPL; T4=50%SPL e T5=25%SPL. Aos 63 dias da semeadura, realizou-se a colheita e mensuraram-se as variáveis: comprimento da parte aérea, da raiz, peso da massa fresca da parte aérea, área foliar e número de folhas de cada indivíduo e a análise química dos substratos. Aplicou-se a ANOVA e o teste de Tukey a 5% de probabilidade. O solo do povoamento da L. auriculata (SPL apresentou uma maior quantidade de nutrientes em relação ao solo da área externa ao povoamento (SAE e influenciou positivamente no crescimento das plantas de alface. No entanto, em apenas três dos cinco tratamentos aplicados (T1, T2 e T3, a alface se desenvolveu. Em T1, T2 e T3 as variáveis analisadas diferiram estatisticamente em função da origem dos solos utilizados e da proporção do esterco bovino. O solo oriundo do povoamento de L. auriculata não apresentou efeito alelopático sobre os parâmetros de crescimento da alface.Seedling growth lettuce (Lactuca sativa L. in soil arising out of a settlement Luetzelburgia auriculata (Allemão DuckeAbstract: This research aimed to know allelopathic characteristics and fertility of the soil arising out settlement Luetzelburgia auriculata (Allemão Ducke by assessing the growth of lettuce plants. Initially

  17. MANEJO DA IRRIGAÇÃO DA CULTURA DA ALFACE (Lactuca sativa L. ATRAVÉS DO TANQUE CLASSE A

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    ANDRADE JÚNIOR A.S. de

    1997-01-01

    Full Text Available Com o objetivo de avaliar o efeito de diferentes níveis de irrigação, baseados em frações da evaporação do Tanque Classe A (ECA (0,25; 0,50; 0,75 e 1,00 sobre o comportamento produtivo da cultura da alface, variedade "Mesa 659" (tipo americana, cultivada em uma estufa plástica e irrigada por gotejamento, foi conduzido um experimento durante o período de julho a setembro de 1993. O comportamento produtivo foi avaliado através da determinação da matéria fresca (MFP, produtividade (PROD e eficiência do uso de água (EUA. Os resultados de MFP e PROD mostraram resposta quadrática, indicando acréscimo em ambos à medida que aumentaram as lâminas de irrigação aplicadas até o nível 0,75 da ECA, apresentando valores máximos de 818,72 g e 90,97 t.ha-1, respectivamente. Os dados relativos à EUA revelaram resposta linear decrescente, significando que à medida que os níveis de irrigação aumentam ocorre uma diminuição na EUA.

  18. Folhas de alface lisa (Lactuca sativa) minimamente processadas armazenadas em atmosfera modificada: análises físicas, químicas e físico-químicas Minimally processed smooth lettuce leaves (Lactuca sativa) stored at modified atmosphere: physica, chemical and physico-chemical analysis

    OpenAIRE

    Ellen M S Menezes; Érica C. Fernandes; Armando U. O. Sabaa-Srur

    2005-01-01

    Alfaces (Lactuca sativa) cv. lisa, após seleção e pré-lavagem, foram lavadas com água clorada a 5ºC contendo 150ppm de cloro residual livre e pH ajustado para 6.0, enxagüadas e centrifugadas por 8 minutos a 2200rpm. Em seguida, foram acondicionadas em embalagens plásticas de nylon poli 5 camadas, sem e com atmosfera modificada (N2 contendo 20ppm de O2 e no máximo 20ppm umidade) e estocadas a 4ºC. Durante 5 dias foram realizadas mensurações de pH, concentração de sólidos solúveis (graus Brix) ...

  19. Aspectos sanitários do cultivo da alface americana, irrigada com águas recptoras de efluentes urbanos Sanitary aspects of lectucce (Lactuca sativa L. culture irrigated with receiving waters of urban effluent

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    Guilherme Augusto Biscaro

    2008-02-01

    Full Text Available Avaliou-se a influência da disposição de mangueiras gotejadoras nos canteiros e a injeção ou não de cloro na água de irrigação, nas condições sanitárias do solo e da alface americana irrigada (Lactuca sativa L. com águas receptoras de efluentes urbanos. Foram realizadas análises microbiológicas de amostras de água do solo e da alface, no decorrer de todo o ciclo de cultivo. Objetivou-se determinar a possível existência de Salmonella spp. e de formas evolutivas de parasitos humanos e a quantidade de coliformes fecais, em pontos e épocas diferentes do experimento, impedindo assim o consumo da alface. Os resultados não indicaram a presença dos dois primeiros em nenhuma das amostras, mas sim de parasitos não humanos (nematóides de vida livre no solo. Em relação à quantidade de coliformes fecais (NMP ml-1, o valor encontrado na cultura atende às exigências da Secretaria de Vigilância Sanitária do Ministério da Saúde brasileiro, porém a presença dos nematóides em quantidades superiores ao permitido pela Organização Mundial de Saúde (OMS inviabiliza o seu consumo.One evaluated the influence of drip tape arrangement and the use of chloride in the irrigation water, on soil sanitary conditions and growing lettuce (Lactuca sativa L., irrigated with receiving urban waters. Water, soil and lettuce microbiological analyses were performed during crop cycle. The objective was to determine the presence of Salmonella spp., evolutive forms of human parasites and the amount of fecal coliforms in different locations and time, avoiding the lettuce consumption. Although results did not indicate the presence of Salmonella spp. and evolutive forms of human parasites in none of the samples but non human parasites (nematodes of free life in soil. Total fecal coliforms count (NMP ml-1 met is according to the Brazilian Ministry of Health, Secretary of Health Surveillance requirements. Yet, the lettuce was not good for human consumption

  20. Influência alelopática de hortelã (Mentha x villosa Huds. sobre emergência de plântulas de alface (Lactuca sativa L. Allelopathic influence of mint (Mentha x villosa Huds. on the emergence of lettuce (Lactuca sativa L. seedlings

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    J.T.L.S. Maia

    2011-01-01

    Full Text Available Objetivou-se com esse trabalho avaliar a interferência de possíveis efeitos alelopáticos de Mentha x villosa Huds. sobre a emergência de Lactuca sativa L. As atividades foram conduzidas em laboratório, no Instituto de Ciências Agrárias (ICA da Universidade Federal de Minas Gerais, em Montes Claros/MG. Foram propostos três tratamentos, sendo esses: solo A, coletado em área cultivada com hortelã no horto medicinal do ICA/UFMG; solo B, coletado em áreas adjacentes e, testemunha (papel germiteste.O delineamento experimental foi inteiramente casualizado (DIC, com sete repetições. As variáveis avaliadas foram: porcentagem e índice de velocidade de emergência. Observou-se que a emergência de plântulas de Lactuca sativa foi significativamente afetada pelo solo A (6,95% se comparada com o solo B (21,71%, representando assim, uma inibição da emergência, ou seja, efeito alelopático da hortelã sobre a emergência de alface. Já o índice de velocidade de emergência (IVE não diferiu significativamente entre os solos testados.This study aimed to assess the interference of possible allelopathic effects of Mentha x villosa Huds. on the germination of Lactuca sativa L. The activities were carried out in laboratory, at the Institute of Agricultural Sciences (ICA of the Federal University of Minas Gerais, Montes Claros, Minas Gerais State, Brazil. The following three treatments were proposed: soil A, collected in area cultivated with mint at the garden of ICA; soil B, collected in adjacent areas; and control (germitest paper. Experimental design was completely randomized (CR, with seven replicates. The evaluated variables were: germination percentage and speed index. The emergence of Lactuca sativa seedlings was significantly affected by soil A (6.95% when compared to soil B (21.71%, indicating thus emergence inhibition, i.e. an allelopathic effect of mint on lettuce emergence. On the other hand, the germination speed index (GSI did not

  1. Folhas de alface lisa (Lactuca sativa minimamente processadas armazenadas em atmosfera modificada: análises físicas, químicas e físico-químicas Minimally processed smooth lettuce leaves (Lactuca sativa stored at modified atmosphere: physica, chemical and physico-chemical analysis

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    Ellen M S Menezes

    2005-03-01

    Full Text Available Alfaces (Lactuca sativa cv. lisa, após seleção e pré-lavagem, foram lavadas com água clorada a 5ºC contendo 150ppm de cloro residual livre e pH ajustado para 6.0, enxagüadas e centrifugadas por 8 minutos a 2200rpm. Em seguida, foram acondicionadas em embalagens plásticas de nylon poli 5 camadas, sem e com atmosfera modificada (N2 contendo 20ppm de O2 e no máximo 20ppm umidade e estocadas a 4ºC. Durante 5 dias foram realizadas mensurações de pH, concentração de sólidos solúveis (graus Brix e análises de acidez (mL NaOH 0,1M/100g folhas de alface. Os produtos sofreram acidificação detectável pela diminuição do pH em ambas as atmosferas. O incremento da acidez foi mostrado, sendo os registros maiores para as amostras controle (sem atmosfera modificada, e não ocorreram variações de graus Brix. Os resultados fizeram concluir que avanços tecnológicos vêm sendo alcançados visando melhorar a qualidade e vida-de-prateleira do vegetal.Lettuce (Lactuca sativa cv. smooth, after being selected and washed, was cleaned with chlorine water at 5ºC, with 150ppm of free chlorine and pH adjusted to 6.0, rinsed and centrifuged for 8 minutes at 2200rpm. Right after, the lettuce leaves were packaged in plastic bags made of nylon poli 5 layers, with and without modified atmosphere (N2 having 20ppm of O2 and 20ppm of maximum moisture and stored at 4ºC. During 5 days there were pH, soluble solids concentration measurements and acid analysis (mL NaOH 0,1M/100g lettuce leaves. The products became acid, detectable by a pH decrease in both atmospheres. A raise in acidity was shown, being the highest marks for the control samples (without modified atmosphere and there was no soluble solids variation. Results have shown that technological progress is being reached aiming to improve the vegetable's quality and shelf life.

  2. Origin and domestication of Lactuca sativa L.

    NARCIS (Netherlands)

    Vries, de I.M.

    1997-01-01

    The domestication of lettuce, Lactuca sativa L. is described on the basis of literature study. The centre of origin is discussed. A historical survey is made of the distribution of the groups of Lactuca cultivars over the world.

  3. DESEMPENHO DE CULTURAS DE ALFACE (LACTUCA SATIVA L NO PERIODO DE VERAO EM CASAS DE VEGETAÇÃO COM DIFERENTES COBERTURAS PERFORMANCE OF THE LETTUCE (LACTUCA SATIVA L ON SUMMER CONDITIONS IN GREENHOUSES WITH DIFFERENT COVERINGS

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    Fernando da Costa Baêta

    2011-06-01

    Full Text Available O presente estudo teve como objetivo avaliar as condições térmicas ambientais no interior de quatro protótipos, iguais em concepção e geometria arquitetônicas e diferentes nas soluções dos componentes de fechamento da cobertura, e avaliar o desempenho deles na produção de alface em períodos de verão. Para fins de avaliação de desempenho ambiental, foram considerados quatro tratamentos de cobertura: (T testemunha, somente com lona plástica; (L lona plástica e componente de ventilação (lanternim; (LS lona plástica sob tela de sombreamento, associado a componente de ventilação (lanternim; e, (S lona plástica sob tela de sombreamento. Como pressupostamente esperado, pode-se afirmar que as casas de vegetação sombreadas apresentaram melhor desempenho ambiental, comparativamente às não-sombreadas, e proporcionaram um ambiente mais confortável ao desenvolvimento da cultura da alface no verão.The aim of this work had concentrated in the study of solutions for the closing of the covering for greenhouses under summer conditions, experimented with the lettuce. Four covering treatments were considerate for the evaluation of the environmental performance: (T testifier, with only plastic canvas; (C plastic canvas and ventilation compound (an overture on the roof; (CS plastic canvas under shading screen, with a ventilation compound(an overture on the roof associated; and (S plastic canvas under shading screen. It can be declared, as expected, that shaded greenhouses presented a best environment performance than the unshaded greenhouses, and provided a more comfortable environment for the growth of lettuce culture on Summer.

  4. Stratification periods in seeds germination of lettuce (Lactuca sativa L. under different conditions of light and temperaturePeríodos de estratificação na germinação de sementes de alface (Lactuca sativa L. sob diferentes condições de luz e temperatura

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    Gisela Ferreira

    2012-06-01

    Full Text Available Lettuce seeds have a high sensitivity to variations in humidity and temperature of the environment where they germinate, therefore, studies with the aim of improve the germination and physiological performance of these have been conducted. Thus, the study aimed to evaluate the efficiency of pre-germination treatment stratification (5 °C for different periods, and increase the uniformity of germination of lettuce seeds submitted to different conditions of light and germination temperatures. In the pre-germinative treatment, the seeds of lettuce (Lactuca sativa L. var. American Great Lakes were placed in plastic boxes dark of the type “gerbox” and subjected to temperature stratification of 5 °C and the dark for 4, 8, 12 and 16 hours. After periods of stratification the seeds were submitted to germination tests which were transferred to plastic boxes type “gerbox” transparent (constant light and dark (no light and were maintained in a germination chamber B.O.D with light constant at temperatures of 20, 25, 30 and 35°C. The design used was the entirely randomized with four repetitions, in a factorial outline 5x4x2, five pre-germinative treatments, four germination temperatures and two light conditions. Stratification for 16 hours and temperatures of 20 and 25 °C stimulated the germination of lettuce seeds, providing a higher germination percentage, germination speed index and minor mean germination time. The presence of light resulted in increased germination at 0, 4, 8 and 12 hours of stratification.As sementes de alface apresentam grande sensibilidade às variações na umidade e temperatura do meio onde germinam e, por isso, estudos com o intuito de melhorar a porcentagem de germinação e o desempenho fisiológico dessas têm sido realizados. Dessa maneira, o trabalho teve como objetivo avaliar a eficiência do tratamento pré-germinativo de estratificação (5°C por diferentes períodos, na uniformização e incremento da germina

  5. PRODUÇÃO E DESENVOLVIMENTO DE TRÊS CULTIVARES DE ALFACE (Lactuca sativa L. SUBMETIDAS A ADUBAÇÃO ORGÂNICA

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    Mário Pechara Jaeggi

    2017-04-01

    Full Text Available O objetivo do estudo foi avaliar doses de adubos orgânica no desevolvimento de três cultivares de alface na região Alegre-ES. O experimento foi instalado em delineamento inteiramente casualizado, em esquema fatorial 3x3, com quatro repetições. Os tratamentos foram três doses de adubação orgânica composto por esterco bovino mais resíduos de gramíneas (1,5; 3,5 e 4,5 kg m-2 e três cultivares de alface (Lucy brow; Regina e Vanda apresentando mesmo tempo fenologico . As análises foram realizadas aos 40 dias após transplantio, sendo mensurados as variáveis biométricas diâmetro do caule; comprimento de raiz; massa fresca da parte aérea e massa fresca total. Pelos resultados obtidos a dose de 4,5 kg m-2 do composto orgânico proporcionou maior ganho em diâmetro do caule, comprimento de raiz, massa fresca da parte aérea e massa fresca da raiz nas três cultivares de alface utilizadas (Lucy brow, Regina e Vanda.

  6. Avaliação parasitológica em alfaces (Lactuca sativa L. comercializadas em Serra Talhada, Pernambuco, Brasil / Parasitological evaluation in lettuces (Lactuca sativa L. marketed in Serra Talhada, Pernambuco, Brazil

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    Rebeca Gonçalves de Oliveira

    2014-08-01

    Full Text Available A prevalência de parasitoses intestinais cresce de forma expansiva no Brasil e em muitos países. A ocorrência de enteroparasitoses advém de várias maneiras, inclusive por con-sumo de vegetais contaminados, representando um grande problema em nível mundial. O objetivo deste trabalho foi avaliar a contaminação por parasitas intestinais em horta-liças comercializadas em Serra Talhada-PE. As amostras das hortaliças foram coletadas nas unidades de produção (hortas, na unidade de recepção do Programa de Aquisição de Alimentos (PAA e em diversos estabelecimentos comerciais localizadas no município. As amostras foram colocadas em sacos plásticos e mantidas em caixa isotérmica; em seguida, foram encaminhadas ao laboratório de Biologia da Unidade Acadêmica de Serra Talhada-UFRPE. Para a identificação dos parasitas foi utilizado o método de sedimenta-ção espontânea. Observou-se que das 80 amostras de alface analisadas 97,5% estavam positivas para formas parasitárias e outros organismos microscópicos, incluindo ovos e larvas de nematoides, cistos de protozoários, ovos de cestódeos e alguns artrópodes (insetos e ácaros. É de suma importância o conhecimento dos produtores e manipu-ladores em geral a respeito da contaminação, bem como o conhecimento das técnicas sanitizantes desenvolvidas para hortaliças, com intuito de diminuir a contaminação em todas as etapas ocorrentes desde o cultivo até ao consumo. ------------------------------------------------------------------------------------- Prevalence of intestinal parasites growing in Brazil and in many countries so expansive. The intestinal parasites comes in several ways, including by consumption of contami-nated vegetables, which represents a significant worldwide problem. The objective of this study is to assess the contamination by intestinal parasites in vegetables commer-cialized in Serra Talhada, in Pernambuco state. Samples of vegetables were collected at the

  7. CRESCIMENTO E DESENVOLVIMENTO DA ALFACE (Lactuca sativa L. CONDUZIDA EM ESTUFA PLÁSTICA COM FERTIRRIGAÇÃO EM SUBSTRATOS GROWTH AND DEVELOPMENT OF LETTUCE (Lactuca sativa L. IN A PLASTIC GREENHOUSE WITH FERTIRRIGATION IN SUBSTRATES

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    Luis Aquiles Martins Medeiros

    2001-04-01

    Full Text Available Foram conduzidos dois experimentos, um cultivo no outono e outro no inverno de 1998, em estufa plástica localizada no Departamento de Fitotecnia da Universidade Federal de Santa Maria, com o objetivo de estudar a influência da fertirrigação em substratos no crescimento e desenvolvimento da alface, cultivar Brisa. Os tratamentos, com e sem fertirrigação, foram constituídos pelos substratos húmus de minhoca mais casca de arroz natural (H+CN, húmus de minhoca mais casca de arroz carbonizada (H+CC e solo como testemunha, constituindo um bifatorial 3x2. A fertirrigação foi realizada em função da condutividade elétrica (CE da solução drenada dos substratos. O delineamento experimental utilizado foi de blocos casualizados com quatro repetições. Semanalmente, foram determinados o número de folhas por planta, a massa fresca e seca da parte aérea das plantas e o índice de área foliar. Avaliou-se, ainda, a capacidade de retenção de água (CRa dos substratos isolados e das misturas, antes e após os cultivos. A CRa dos substratos aumentou ao longo dos cultivos enquanto a do solo permaneceu constante. Os substratos irrigados com solução nutritiva proporcionaram maior número de folhas, maior produção de massa fresca e seca da parte aérea e maior índice de área foliar do que quando irrigados apenas com água, sendo que os substratos H+CN e H+CC foram significativamente mais produtivos do que o substrato testemunha em ambos os cultivosIn order to study the effects of fertirrigation in growing substrates on the development of lettuce cultivar Brisa, two essays were conducted, one during the fall of 1998 and the other during the winter, in a plastic greenhouse in the Federal University of Santa Maria. The treatments with and without fertirrigation were constituted by earthworm humus plus rice hulls (H+CN, earthworm humus plus carbonized rice hulls (H+CC and pure soil as check. The fertirrigation timing was established by monitoring

  8. Bioatividade de extratos hidroalcoólicos de Cymbopogon citratus (DC. Stapf. sobre picão-preto (Bidens pilosa L. e alface (Lactuca sativa L. Bioactivity of hydroalcoholic extracts of Cymbopogon citratus (DC. Stapf. on germination and early growth of beggartick (Bidens pilosa L. and lettuce (Lactuca sativa L.

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    L.L. Lousada

    2012-01-01

    Full Text Available Este trabalho visou avaliar a bioatividade de extratos hidroalcoólicos de capim-limão sobre germinação e crescimento inicial da planta daninha picão-preto (Bidens pilosa L. e da planta teste alface (Lactuca sativa L.. A partir de maceração hidroalcoólica de folhas secas e rasuradas (127,46 g de capim-limão em 1L de álcool de cereais (70%, foram preparados os tratamentos como extratos hidroalcoólicos (HA pela diluição (v/v do macerado filtrado em água deionizada na proporção 1:1 (HA1:1 e 1:2 (HA1:2; dos quais foram obtidos os respectivos extratos secos (ES, a partir da evaporação da fase líquida de duas alíquotas de 50 mL de cada extrato HA, que após re-suspendidas em igual volume de água, sendo uma autoclavada (1 atm por 15 minutos, resultando nos extratos secos de HA1:1 e HA1:2 autoclavados (ES1:1A e ES1:2A e nos extratos secos não autoclavados (ES1:1 e ES1:2; e água (AG como controle. No primeiro dia dos bioensaios, foram aplicados 2 mL dos tratamentos, em DIC, com cinco repetições. Avaliou-se a porcentagem de germinação (G%, Índice de Velocidade de Germinação (IVG, altura da parte aérea (AA e comprimento de radícula (CR de aquênios (25 de picão-preto e de alface distribuídos em placas de Petri e mantidos em câmara de germinação (B.O.D. por duas semanas. Os extratos HA1:1 e HA1:2 inibiram a G%, AA e CR das duas espécies. Todos os extratos secos reduziram a G%, IVG e o CR da alface. Para o picão preto, apenas o extrato ES1:1 reduziu a G% e o IVG foi reduzido por todos os extratos, a exceção do ES1:1A, mas nenhum extrato influenciou o crescimento inicial desta espécie.This study aimed to evaluate the bioactivity of hydroalcoholic extract of lemongrass on the germination and early growth of the weed plant beggartick (Bidens pilosa L. and the test plant lettuce (Lactuca sativa L.. From the hydroalcoholic maceration of dried and cut leaves of lemon grass (127.46 g in 1 L grain alcohol (70%, the following

  9. Uso do rejeito da dessalinização de água salobra no cultivo da alface (Lactuca sativa L. em sistema hidropônico NFT Use of the desalted wastewater for lettuce (Lactuca sativa L. production in NFT hydroponic system

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    Rafaelly Suzanye da Silva Santos

    2010-08-01

    Full Text Available A dessalinização por osmose reversa tem sido bastante utilizada para o tratamento de água salobra, possibilitando a sua utilização para o consumo humano, especialmente em regiões semiáridas. Esse processo tem um fator limitante que é a produção de um rejeito de água com alta salinidade. Com o objetivo de avaliar os efeitos da utilização de água de rejeito da dessalinização no cultivo de alface cultivar Vera (Lactuca sativa L. em sistema hidropônico NFT foi conduzido um experimento em casa de vegetação no departamento de ciências ambientais da UFERSA, em delineamento em blocos casualizados, com seis tratamentos e quatro repetições. Os níveis de salinidade da água entre os tratamentos foram obtidos com, ou sem a necessidade de diluição da água de rejeito da dessalinização acrescido da solução nutritiva com salinidade de 1 dS m-1 (100% de água potável de abastecimento - 1,4 dS m-1; 85% abastecimento e 15% água de rejeito - 1,9 dS m-1; 75 % água de rejeito + 25 % água de abastecimento - 2,7 dS m-1; 50% água de rejeito e 50% água de abastecimento - 3,8 dS m-1; 25 % água de rejeito e 75 % água de abastecimento - 4,9 dS m-1 e água de rejeito coletada no dessalinizador - 5,5 dS m-1. Os parâmetros analisados foram área foliar, diâmetro do caule, número de folhas, peso de matéria fresca e o peso de matéria seca. Todas as variáveis estudadas foram influenciadas negativamente de forma linear pelo efeito da concentração de sais na água de irrigação, sendo que a área foliar e a matéria fresca da parte aérea são as que melhor representam a sensibilidade ao estresse salino na cultivar estudada, tendo a produção em termos de matéria fresca uma redução de 94,83%, ao se elevar a CEa de 1,4 a 5,5 dS m-1.The desalination process by reverse osmosis was used for the treatment of brackish water, making possible the usage human consume in semiarid zones. This process has a limiting factor: it produces

  10. Avaliação da contaminação por enteroparasitas em alfaces (lactuca sativa comercializadas em restaurantes com alimentos expostos ao consumo no município de Sorocaba/SP

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    Caio Vieira Magalhães Ornelas

    2015-10-01

    Full Text Available Diante de um cotidiano pauta do por uma intensa influência dos meios decomunicação a respeito da alimentação saudável e de baixo teor calórico,bem como de um progressivo número de campanhas sociais combatendoa obesidade e seu alto valor epidemiológico sobre a sociedadecontemporânea, as hortaliças têm recebido ampla ênfase no cenárionutricional dos dias de hoje. Entretanto, tais aspectos são tambémacompanhados de extrema cautela, uma vez que as hortaliças sãoimportantes veículos de infecções ao organismo humano através de umavasta gama de possíveis parasitas, devido à manipulação pré-consumo einclusive o consumo cru. O trabalho que se segue teve como objetivopesquisar a presença de enteroparasitas especificamente em alfacescomercializadas em restaurantes com alimentos expostos ao consumo nomunicípio de Sorocaba-SP. As amostras de alface crespa (Lactuca sativacoletadas foram submetidas a uma série de etapas para análise:inicialmente houve lavagem em sacos plásticos durante 30 minutos,seguida de sedimentação do líquido por 24 horas e, por fim, análiseparasitológica da amostra por microscopia óptica. Das 40 amostrasrealizadas, apenas 5% continham enteroparasitas. Outras duas amostrascontinham achados como Paramecium spp. e ácaro. Os resultadosreforçam a necessidade de um a boa higienização das hortaliças, mas,devido ao grande número de restaurantes em Sorocaba comparado com ode amostras coletadas, é inadequado considerar generalizar a premissade que os restaurantes self-service possuam alfaces crespa (Lactucasativa higienizadas e próprias para o consumo em Sorocaba.

  11. Potenciação alelopática de extratos vegetais na germinação e no crescimento inicial de picão-preto e alface Allelopathy of plant extracts on germination and initial growth of beggartick (Bidens pilosa L. and lettuce (Lactuca sativa L.

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    Magda Cristiani Ferreira

    2007-08-01

    Full Text Available O picão-preto (Bidens pilosa L. é uma planta daninha muito agressiva, que está presente em quase todo Brasil. O principal método de controle é o químico, porém apresenta elevado impacto ambiental, risco de intoxicação humana e possibilidade de causar fitotoxicidade as culturas. O objetivo do trabalho foi avaliar o efeito alelopático de extratos etanólicos de Eucalyptus citriodora Hook. e Pinus elliottii L. na germinação e no crescimento inicial de picão-preto e alface (Lactuca sativa L.. Foram testadas quatro concentrações de cada extrato (0,25; 0,50; 1,0 e 2,0 % além do controle (0,0 % água destilada com Tween 20 a 0,08 %. O delineamento experimental foi o inteiramente casualizado, com quatro repetições em condições de laboratório. O extrato de P. elliottii não causou efeito alelopático sobre o picão-preto e o alface. O extrato de E. citriodora reduziu significativamente o índice de velocidade de germinação (IVG do picão-preto em todas as concentrações testadas quando comparadas com o controle (0,0%, porém para a alface o IVG foi significativo apenas na concentração de 2,0 %. Para o comprimento da raiz não foi possível observar diferença significativa entre os tratamentos para os dois extratos testados tanto para o alface como para o picão preto.Bidens pilosa L. is an aggressive weed found all over Brazil. The main control method for this species is chemical treatment however, causes strong environmental impact, and it has great human contamination risks, and may cause phytotoxity to crops. The objective of this study was to evaluate the effect of ethanolic extracts of Eucalyptus citriodora Hook. and Pinus elliottii L. on seed germination and initial growth of B. pilosa and lettuce (Lactuca sativa L.. Five concentrations of each extract (0.0; 0.25; 0.50; 1.0; 2.0% were tested in laboratory conditions using a randomized complete block design with four replicates. P. elliottii extract had no effect on B

  12. Avaliação parasitológica de alfaces (Lactuca sativa comercializadas em feiras livres e supermercados do município de Campo Mourão, Estado do Paraná - DOI: 10.4025/actascibiolsci.v26i4.1514 Occurence of parasites in lettuce (Lactuca sativa commercializaed in the street markets and supermarkets of Campo Mourão, state of Paraná, Brazil - DOI: 10.4025/actascibiolsci.v26i4.1514

    Directory of Open Access Journals (Sweden)

    Sandra Maria Simonelli

    2004-04-01

    Full Text Available Este estudo investigou e comparou a contaminação por enteroparasitas em alfaces (Lactuca sativa comercializadas em supermercados e feiras livres do município de Campo Mourão, Estado do Paraná. Foram analisadas 150 amostras de alfaces, pelo método de sedimentação espontânea (Hoffmann, sendo 75 amostras provenientes de supermercados e 75 amostras de feiras livres. O sedimento foi analisado em microscópio óptico. Das amostras analisadas, 56% (42/75 e 58,7% (44/75 apresentaram contaminação por parasitas, dos supermercados e feiras livres, respectivamente. Os principais parasitas encontrados em supermercados foram: Ascaris spp 54,7%, Toxocara spp 2,4%, Strongyloides spp 4,8%, Entamoeba spp 35,7% e Taenia spp 2,4%; e em feiras livres foram: Ascaris spp 13,6%, Strongyloides spp 11,4%, Entamoeba spp 47,7%, Ancylostoma spp 9,1%, /em>Taenia spp 2,3%, Fasciola hepatica 6,8% e Trichuris spp 9,1%. Esses resultados indicam que as amostras de alfaces estão em desacordo com a legislação vigente e salientam a necessidade de aplicação de um programa de educação sanitária direcionado a horticultores e manipuladores de hortaliçasThis work researched and compared the contamination by enteroparasites in lettuce (Lactuca sativa commercialized in the supermarkets and street markets of Campo Mourão, State of Paraná. 150 samples of lettuce were analyzed through sedimentation method (Hoffmam, being 75 samples from supermarkets and 75 from street markets. The sediment was analyzed in optic microscope. The supermarkets samples showed contamination by parasites of 56% (42/75; while contamination of street markets samples showed 58.7% (44/75. The principal parasites observed in supermarkets samples were: Ascaris spp 54.7%, Toxocara spp 2.4%, Strongyloides spp 4.8%, Entamoeba spp 35.7% and Taenia spp 2.4%. Important parasites observed in street markets were: Ascaris spp 13.6%, Strongyloides spp 11.4%, Entamoeba spp 47.7%, Ancylostoma spp 9.1%, Taenia

  13. Produtividade da alface (Lactuca sativa L. em resposta à aplicação de ácidos húmicos e bactérias diazotróficas, em condições de campo

    Directory of Open Access Journals (Sweden)

    Ana Flávia Mairinck Meirelles

    Full Text Available RESUMO A alface é uma das hortaliças folhosas mais consumidas no Brasil, gerando grande demanda por seu cultivo. É cultura exigente em nutrientes e requer solo rico em matéria orgânica para obtenção de produtividade elevada, com necessidade de aplicação de grandes doses de compostos orgânicos, onerando os custos da produção. Ácidos húmicos (AH e bactérias diazotróficas (B apresentam hormônios vegetais, como auxinas, que promovem alongamento celular, aumento das raízes e da absorção de nutrientes, levando ao crescimento e desenvolvimento das plantas. Por essas características, podem ser utilizados como bioestimulantes na promoção da produtividade da alface. O objetivo deste trabalho foi avaliar a produtividade da alface em resposta à aplicação de ácidos húmicos e bactérias diazotróficas, em condições de campo. Os ácidos húmicos foram isolados de esterco bovino e as bactérias usadas foram provenientes da coleção de bactérias do Setor de Floricultura da Universidade Federal de Viçosa - Campus Florestal, extraídas de orquídeas Cymbidium sp.. O experimento foi realizado em condições de campo, com o cv. Vanda e os tratamentos usados foram controle (cultivo convencional do produtor, aplicação isolada de ácido húmico e bactéria e aplicação combinada de ácido húmico+bactéria. O delineamento adotado foi em blocos casualizados, com cinco repetições. A aplicação dos bioestimulantes foi realizada logo após o transplantio. Foram avaliados atributos fitotécnicos da parte aérea das plantas. Concluiu-se que os tratamentos utilizados, principalmente a combinação AH+B, aumentaram a produtividade da alface.

  14. Genetic transformation of lettuce (Lactuca sativa): A review

    African Journals Online (AJOL)

    SAM

    2014-04-16

    Apr 16, 2014 ... Lettuce (Lactuca sativa L.) is a globally important leafy vegetable that can be grown worldwide. Due to the rapid growth of population and the human desire to progress, there have been a lot of studies made by researchers, especially in genetic engineering. Improvements in regeneration system and.

  15. Genetic transformation of lettuce ( Lactuca sativa ): A review | Dan ...

    African Journals Online (AJOL)

    Lettuce (Lactuca sativa L.) is a globally important leafy vegetable that can be grown worldwide. Due to the rapid growth of population and the human desire to progress, there have been a lot of studies made by researchers, especially in genetic engineering. Improvements in regeneration system and transformation ...

  16. [Analysis of essential oil extracted from Lactuca sativa seeds growing in Xinjiang by GC-MS].

    Science.gov (United States)

    Xu, Fang; Wang, Qiang; Haji, Akber Aisa

    2011-12-01

    To analyze the components of essential oil from Lactuca sativa seeds growing in Xinjiang. The components of essential oil from Lactuca sativa seeds were analyzed by gas chromatography-mass spectrometry (GC-MS). 62 components were identified from 71 separated peaks,amounting to total mass fraction 95.07%. The dominant compounds were n-Hexanol (36.31%), n-Hexanal (13.71%), trans-2-Octen-l-ol (8.09%) and 2-n-Pentylfuran (4.41%). The research provides a theoretical basis for the exploitation and use of Lactuca sativa seeds resource.

  17. Qualidade da alface crespa minimamente processada acondicionada em atmosfera modificada

    OpenAIRE

    Roversi,Rosana Mendes; Masson,Maria Lucia

    2004-01-01

    A alface Crespa (Lactuca sativa L.)foi minimamente processada, tendo suas folhas destacadas e higienizadas, embalada em sacos plásticos de polietileno com modificação ativa da atmosfera dentro do pacote. Duas atmosferas foram aplicadas, variando-se o nível de CO2 em 10 e 15%, reduzindo nos dois casos o O2 a 5%. Após o acondicionamento, a alface foi imediatamente refrigerada. Comparou-se a qualidade da alface com e sem atmosfera modificada durante o armazenamento refrigerado. Monitoraram-se a ...

  18. Efeito alelopático de folhas de bamburral [Hyptis suaveolens (L. Poit.] sobre a germinação de sementes de sorgo (Sorghum vulgare Pers., rabanete (Raphanus sativus L. e alface (Lactuca sativa L. Allelopathic effects of leaves of "bamburral" [Hyptis suaveolens (L. Poit.] on the germination of seeds of sorghum (Sorghum vulgare Pers. , radish (Raphanus sativus L. and lettuce (Lactuca sativa L.

    Directory of Open Access Journals (Sweden)

    A.C. Rodrigues

    2012-01-01

    Full Text Available O objetivo do presente trabalho foi à verificação do efeito alelopático de Hyptis. suaveolens na germinação de sorgo, alface e rabanete, bem como, a comprovação da existência de compostos com potencial alelopático. Sementes de sorgo, alface e rabanete foram semeadas em substrato constituído de areia, terra e adubo orgânico contendo folhas de H. suaveolens. As análises da germinação foram feitas considerando a protrusão da radícula para o término do evento germinativo. Foi calculado o IVG (índice de velocidade de germinação e %G (porcentagem de germinação. Os resultados mostraram que sorgo e a alface foram mais susceptíveis ao potencial alelopático de H. suaveolens, sendo que para o rabanete foi observado um efeito benéfico. Entre os tratamentos, o substrato esterilizado e não esterilizado mostraram diferenças entre si. A análise cromatográfica do óleo essencial presente nas folhas de H. suaveolens revelou a presença de compostos com potencial alelopático. Portanto, H. suaveolens, pode apresentar efeito alelopático positivo no IVG de sementes de rabanete e a presença de microorganismos pode ser necessária para que esse efeito alelopático aconteça.The aim of this study was to verify the allelopathic effect of H. suaveolens on the germination of sorghum, lettuce and radish, as well as to prove the existence of compounds with allelopathic potential. Seeds of sorghum, lettuce and radish were sown in substrate consisting of sand, soil and organic fertilizer containing leaves of H. suaveolens. The germination tests were performed considering the protrusion of the radicle for the conclusion of the germinative event. GSI (germination speed index and G% (percentage of germination were calculated. The results showed that sorghum and lettuce were more susceptible to the allelopathic potential of H. suaveolens, while for radishes a beneficial effect was observed. Between treatments, the sterilized and unsterilized

  19. Halogenated auxins affect microtubules and root elongation in Lactuca sativa

    Science.gov (United States)

    Zhang, N.; Hasenstein, K. H.

    2000-01-01

    We studied the effect of 4,4,4-trifluoro-3-(indole-3-)butyric acid (TFIBA), a recently described root growth stimulator, and 5,6-dichloro-indole-3-acetic acid (DCIAA) on growth and microtubule (MT) organization in roots of Lactuca sativa L. DCIAA and indole-3-butyric acid (IBA) inhibited root elongation and depolymerized MTs in the cortex of the elongation zone, inhibited the elongation of stele cells, and promoted xylem maturation. Both auxins caused the plane of cell division to shift from anticlinal to periclinal. In contrast, TFIBA (100 micromolar) promoted elongation of primary roots by 40% and stimulated the elongation of lateral roots, even in the presence of IBA, the microtubular inhibitors oryzalin and taxol, or the auxin transport inhibitor naphthylphthalamic acid. However, TFIBA inhibited the formation of lateral root primordia. Immunostaining showed that TFIBA stabilized MTs orientation perpendicular to the root axis, doubled the cortical cell length, but delayed xylem maturation. The data indicate that the auxin-induced inhibition of elongation and swelling of roots results from reoriented phragmoplasts, the destabilization of MTs in elongating cells, and promotion of vessel formation. In contrast, TFIBA induced promotion of root elongation by enhancing cell length, prolonging transverse MT orientation, delaying cell and xylem maturation.

  20. Isolation and culture of protoplast from leaves of Lactuca sativa

    Directory of Open Access Journals (Sweden)

    Witool Chaipakdee

    2007-07-01

    Full Text Available Protoplasts were isolated from leaves of lettuce (Lactuca sativa L. seedlings after in vitro germination for 25, 30, 40 and 50 days. The leaves were stripped and incubated in various combinations of cellulase and pectinase. Protoplasts were cultured on MS medium containing various kinds and concentrations of plant growth regulators in different culture systems including liquid media, hanging, drop culture and solid media. Results revealed that the highest number of viable protoplasts, 14.1x105 cells per gram of fresh weight, was obtained from 30 day-old leaves of lettuce seedlings and isolated by using 2% cellulase in combination with 1% pectinase. Liquid MS medium supplemented with 0.5 mg/l NAA and 0.5 mg/l BA promoted the highest cell division up to 17.67%. First division of protoplasts was observed at 4 days after culture and microcolony formation occurred at the 4th week after culturing. Unfortunately, neither callus formation nor plantlet regeneration were obtained.

  1. Initiation and elongation of lateral roots in Lactuca sativa

    Science.gov (United States)

    Zhang, N.; Hasenstein, K. H.

    1999-01-01

    Lactuca sativa cv. Baijianye seedlings do not normally produce lateral roots, but removal of the root tip or application of auxin, especially indole-butyric acid, triggered the formation of lateral roots. Primordia initiated within 9 h and were fully developed after 24 h by activating the pericycle cells opposite the xylem pole. The pericycle cells divided asymmetrically into short and long cells. The short cells divided further to form primordia. The effect of root tip removal and auxin application was reversed by 6-benzylaminopurine at concentrations >10(-8) M. The cytokinin oxidase inhibitor N1-(2chloro4pyridyl)-N2-phenylurea also suppressed auxin-induced lateral rooting. The elongation of primary roots was promoted by L-alpha-(2-aminoethoxyvinyl) glycine and silver ions, but only the latter enhanced elongation of lateral roots. The data indicate that the induction of lateral roots is controlled by basipetally moving cytokinin and acropetally moving auxin. Lateral roots appear to not produce ethylene.

  2. Potentiating Effects of Lactuca sativa on Pentobarbital-Induced Sleep.

    Science.gov (United States)

    Ghorbani, Ahmad; Rakhshandeh, Hassan; Sadeghnia, Hamid Reza

    2013-01-01

    Traditionally, Lactuca sativa (lettuce) has been recommended for its hypnotic property. The present study was planned to investigate sleep-prolonging effect of this plant. The hydro-alcoholic extract (HAE) of lettuce and its water fraction (WF), ethyl acetate fraction (EAF), and n-butanol fraction (NBF) were administrated (IP) to mice 30 min before the pentobarbital injection. Moreover, both in-vivo and in-vitro toxicity of the extracts were determined. The quality of HAE and NBF was also evaluated using HPLC fingerprint. The HAE prolonged the pentobarbital-induced sleep duration at dose of 400 mg/Kg. The NBF was the only fraction which could increase the sleep duration and decrease sleep latency. The effects of NBF were comparable to those of induced by diazepam. The LD50-value for HAE was found to be 4.8 g/Kg. No neurotoxic effect was observed either by HAE or by its fractions in cultured PC12 neuron-like cells. The results suggest that lettuce potentiates pentobarbital hypnosis without major toxic effect. The main component(s) responsible for this effect is most likely to be non-polar agent(s) which found in NBF of this plant.

  3. Anxiolytic property of hydro-alcohol extract of Lactuca sativa and its effect on behavioral activities of mice.

    Science.gov (United States)

    Harsha, Singapura Nagesh; Anilakumar, Kandangath Raghavan

    2013-01-01

    Lactuca sativa, belonging to the Asteraceae family, is a leafy vegetable known for its medicinal properties. This study aimed to understand the mechanism of Lactuca sativa extract with respect to pharmacological action.We investigated the anxiolytic effects of hydro-alcoholic extract of leaves of Lactuca sativa on mice. The behavioral tests performed on mice models to assess anti-anxiety properties were: open field test (OFT), elevated plus maze test (EPM), elevated T maze test, and marble burying test. Increased locomotor activity and time spent in the "open-arm" were observed in extract fed group. Malondialdehyde (MDA) and nitrite levels were decreased, catalase and glutathione levels were increased in Lactuca sativa treated mice. The data obtained in the present study suggests that the extract of Lactuca sativa can afford significant protection against anxiolytic activity.

  4. TOXICITY OF METHYL-TERT BYTYL ETHER (MTBE) TO PLANTS (AVENA SATIVA, ZEA MAYS, TRITICUM AESTIVUM, AND LACTUCA SATIVA)

    Science.gov (United States)

    Effects of Methyl tert-butyl ether (MTBE) on the germination of seeds and growth of the plant were studied in some laboratory experiments. Test plants were wild oat (Avena sative), sweet corn (Zea mays), wheat (Triticum aestivum), and lettuce (Lactuca sativa). Seed germination,...

  5. Pb low doses induced genotoxicity in Lactuca sativa plants.

    Science.gov (United States)

    Silva, S; Silva, P; Oliveira, H; Gaivão, I; Matos, M; Pinto-Carnide, O; Santos, C

    2017-03-01

    Soil and water contamination by lead (Pb) remains a topic of great concern, particularly regarding crop production. The admissible Pb values in irrigation water in several countries range from ≈0.1 to ≈5 mg L -1 . In order to evaluate putative effects of Pb within legal doses on crops growth, we exposed Lactuca sativa seeds and seedlings to increasing doses of Pb(NO 3 ) 2 up to 20 mg L -1 . The OECD parameter seed germination and seedling/plant growth were not affected by any of the Pb-concentrations used. However, for doses higher than 5 mg L -1 significant DNA damage was detected: Comet assay detected DNA fragmentation at ≥ 5 mg L -1 and presence of micronuclei (MN) were detected for 20 mg L -1 . Also, cell cycle impairment was observed for doses as low as 0.05 mg L -1 and 0.5 mg L -1 (mostly G 2 arrest). Our data show that for the low doses of Pb used, the OECD endpoints were not able to detect toxicity, while more sensitive endpoints (related with DNA damage and mitotic/interphase disorders) identified genotoxic and cytostatic effects. Furthermore, the nature of the genotoxic effect was dependent on the concentration. Finally, we recommend that MN test and the comet assay should be included as sensitive endpoints in (eco)toxicological assays. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  6. Estimation of Folate (Vitamin B9) in fresh Lactuca sativa (Lettuce ...

    African Journals Online (AJOL)

    An attempt was made to extract and estimate Vitamin B9 (folate) from 3 different vegetables namely Lactuca sativa (Lettuce), Spinacia oleracea (Spinach) and Brassica oleracea (Cabbage) from four locations using dibasic potassium phosphate at a temperature of 60 ° UV double beam spectrophotometer was used to ...

  7. Phosphomannose isomerase gene for selection in lettuce (Lactuca sativa L.) transformation

    Czech Academy of Sciences Publication Activity Database

    Bříza, Jindřich; Růžičková, N.; Niedermeierová, Hana; Dusbábková, Jana; Vlasák, Josef

    2010-01-01

    Roč. 57, č. 1 (2010), s. 63-68 ISSN 0001-527X Institutional research plan: CEZ:AV0Z50510513 Keywords : pmi * npt II * Lactuca sativa Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.234, year: 2010

  8. Plant Age Affects Wound-Induced Senescense in Lactuca Sativa L

    NARCIS (Netherlands)

    Witkowska, I.M.; Woltering, E.J.

    2014-01-01

    In the present study we investigated the performance of dark-stored wounded leaf discs and pieces (to some extent mimicking fresh-cut product) of Lactuca sativa L. in relation to the physiological maturity at harvest. We used two related genotypes, i.e. a green (cv. Troubadour) and a red butterhead

  9. Development of genomic SSR markers for fingerprinting lettuce (Lactuca sativa L.) cultivars and mapping genes

    Science.gov (United States)

    Background: Lettuce (Lactuca sativa L.) is the major vegetable from the group of leafy vegetables. Several types of molecular markers were developed that are effictively used in lettuce breeding and genetic studies. However only a very limited number of microsattelite-based markers are publicly avai...

  10. Effect of mancozeb-treated lettuce ( Lactuca sativa ) on wistar rat liver

    African Journals Online (AJOL)

    Because mancozeb, ethylene bis-dithiocarbamate, is mainly used, more than five times, during the growth of lettuce (Lactuca sativa), the aim of the present investigation is to evaluate the potential effect of mancozeb-treated lettuce on the rat liver physiology. Mancozeb-treated lettuce and two doses of mancozeb were ...

  11. Allelopathic effect of medicinal plant Cannabis sativa L. on Lactuca sativa L. seed germination

    Directory of Open Access Journals (Sweden)

    Homa MAHMOODZADEH

    2015-11-01

    Full Text Available In order to examine allelopathic effect of Cannabis sativa L. on germination capability and seedling growth of Lactuca sativa L., a study was performed in laboratory conditions. Treatments were set up in randomised block design in four replications for each of four concentration ranges of 25, 50, 75 and 100 % of aqueous extract made of shoot parts and 4 identical extract concentrations made of root of cannabis. Control variant was lettuce seed treated by distilled water. During the studies shoot and seminal root length of lettuce seedlings were measured after treatments with different concentrations of extracts made of root and shoot parts of cannabis, and the obtained values were compared with the control. The obtained results suggest that the extract from the shoot parts of cannabis in high concentrations of 75 and 100 % had inhibiting effect to the germination indices while the extract from the root had no statistically significant effect on germination of lettuce seeds. Extract made of root part of cannabis showed also stimulatory effect to shoot and seminal root length of lettuce seedlings in extract concentrations of 50, 75 and 100 %.

  12. SSH reveals a linkage between a senescence-associated protease and Verticillium wilt symptom development in lettuce (Lactuca sativa)

    Science.gov (United States)

    Suppression subtractive hybridization (SSH) was employed to identify lettuce (Lactuca sativa) genes that are differentially expressed in symptomatic leaves infected with Verticillium dahliae. Genes expressed only in symptomatic leaves included those with homology to pathogenesis-related (PR) protei...

  13. Potencial alelopático de espécies nativas na germinação e crescimento inicial de Lactuca sativa L. (Asteraceae Allelopathic potential of native species in Lactuca sativa L. (Asteraceae germination and initial growth

    Directory of Open Access Journals (Sweden)

    Fabiana Maraschin-Silva

    2006-03-01

    Full Text Available A alelopatia caracteriza-se pelos efeitos danosos ou benéficos sobre o desenvolvimento da vegetação, causados por substâncias químicas produzidas e liberadas para o ambiente por uma planta. Com o objetivo de avaliar o potencial alelopático de espécies brasileiras, foram testados extratos foliares de Cecropia pachystachya Trec. (Urticaceae, Peltophorum dubium (Spreng. Taub. (Fabaceae, Psychotria leiocarpa Cham. & Schltdl (Rubiaceae, Sapium glandulatum (Vell. Pax (Euphorbiaceae e Sorocea bonplandii (Baill. Burg., Lanj. & Boer (Moraceae, utilizando-se bioensaios de germinação e crescimento e alface (Lactuca sativa L. como planta alvo. Nesses bioensaios, foram usados extratos foliares aquosos nas concentrações de 2 e 4%, preparados por maceração estática com água fria e quente. Os extratos das cinco espécies causaram atraso na germinação dos aquênios da alface, bem como efeitos tóxicos no crescimento das plântulas, com redução e enfraquecimento das raízes. Os resultados obtidos mostraram a presença de substâncias químicas inibidoras nos extratos, revelando potencial alelopático para as cinco espécies avaliadas.Allelopathy is characterized by harmful or beneficial effects on vegetation development, caused by chemical substances produced and released into the environment by the plant. Aiming to assess the allelopathic potential of Brazilian species, aqueous leaf extracts of Cecropia pachystachya Trec. (Urticaceae, Peltophorum dubium (Spreng. Taub. (Fabaceae, Psychotria leiocarpa Cham. & Schltdl (Rubiaceae, Sapium glandulatum (Vell. Pax (Euphorbiaceae, and Sorocea bonplandii (Baill. Burger, Lanj. & Boer (Moraceae were tested on lettuce using germination and growth bioassays. In these bioassays, aqueous leaf extracts were used at concentrations of 2 and 4%, prepared by static maceration with cold and hot water. The five species extracts delayed lettuce germination and produced toxic effects on seedling growth, with root

  14. Peculiarities of the formation of lettuce (Lactuca sativa L. varieties collection with reference characteristics

    Directory of Open Access Journals (Sweden)

    Н. В. Лещук

    2014-12-01

    Full Text Available Peculiarities of the formation of the collection of lettuce (Lactuca sativa L. varieties with reference characteristics are considered. Methodological requirements for the formation, grouping, maintenance, use and updating of the examples varieties collection for identifi cation of all lettuce varieties were scientifi cally grounded. Varieties with relevant morphological characteristics and notes of their expressions for vegetative and generative organs of lettuce plants were identifi ed. The use of formed examples varieties collection for the table of characteristics in the Guidelines for the conduct of tests for distinctness, uniformity and stability for lettuce (Lactuca sativa L. varieties was confi rmed.

  15. [Analysis of the mineral elements of Lactuca sativa under the condition of different spectral components].

    Science.gov (United States)

    Chen, Xiao-Li; Guo, Wen-Zhong; Xue, Xu-Zhang; Wang, Li-Chun; Li, Liang; Chen, Fei

    2013-08-01

    Mineral elements absorption and content of Lactuca sativa under different spectral component conditions were studied by ICP-AES technology. The results showed that: (1) For Lactuca sativa, the average proportion for Ca : Mg : K : Na : P was 5.5 : 2.5 : 2.3 : 1.5 : 1.0, the average proportion for Fe : Mn : Zn : Cu : B was 25.9 : 5.9 : 2.8 : 1.1 : 1.0; (2) The absorptions for K, P, Ca, Mg and B are the largest under the LED treatment R/B = 1 : 2.75, red light from fluorescent lamps and LED can both promote the absorptions of Fe and Cu; (3)The LED treatments exhibiting relatively higher content of mineral elements are R/B = 1 : 2.75 and R/W = 1 : 1 while higher dry matter accumulations are R/B = 1 : 2.75 and B/W = 1 : 1.

  16. Inhibitory effect of marine green algal extracts on germination of Lactuca sativa seeds.

    Science.gov (United States)

    Choi, Jae-Suk; Choi, In Soon

    2016-03-01

    The allelopathic potential of nine green seaweed species was examined based on germination and seedling growth of lettuce (Lactuca sativa L.). Out of nine methanol extracts, Capsosiphon fulvescens and Monostroma nitidum extracts completely inhibited germination of L. sativa at 4 mg/filter paper after 24 hr of treatment. Water extracts of these seaweeds generally showed low anti-germination activities than methanol extracts. Of the nine water extracts, Enteromorpha linza extract completely inhibited L. sativa germination at 16 mg/filter paper after 24 hrs. To identify the primary active compounds, C. fulvescens. powder was successively fractionated according to polarity, and the main active agents against L. sativa were determined to be lipids (0.0% germination at 0.5 mg of lipids/paper disc). According to these results, extracts of C. fulvescens can be used to develop natural herbicidal agents and manage terrestrial weeds.

  17. Effects of kaurane diterpene derivatives on germination and growth of Lactuca sativa seedlings.

    Science.gov (United States)

    Vieira, Henriete S; Takahashi, Jacqueline A; Pimenta, Lúcia P S; Boaventura, Maria Amélia D

    2005-01-01

    Kaurenoic and grandiflorenic acid, isolated from Wedelia paludosa (Asteraceae), some derivatives from these acids (alcohols, esters, amides, lactones, oximes) and other naturally occurring kaurane diterpenes were tested for their action on the growth of radical and shoot of Lactuca sativa. Gibberellic acid, GA3, a commercially available phytohormone, belonging to the same class of diterpenes, was also tested. Some of the tested substances showed a remarkable activity either in the inhibition or in stimulation of L. sativa growth. The activity, in some cases, was even higher than that of GA3.

  18. Toxicity Effect of Cr Stress on Seed Germination and Seedling Growth in Lactuca Sativa

    Science.gov (United States)

    Ma, Wan Zheng; Ma, Wan Min; Du, Ying Ying; Dan, Qiong Peng; Yin, Bing; Dai, Shan Shan; Hao, Xiang

    2018-03-01

    The impact of Cr6+ on the growth of lactuca sativa in Greenhouse Cucumber was investigated. The seeds of lacuna sativa Italian bolting resistance lettuce were treated by different Cr6+ concentration to study the effects on its seed germination and seedling growth. The results showed that the seed germination rate, vigor index of seedlings decreased with increment of Cr6+ concentration to varying degrees, and vigor germination, vigor index, raw weight, root length significantly lower. The absorption of lettuce seedlings on different nutrient elements is impacted by the concentration of Cr6+.

  19. Carotenoids of Lettuce (Lactuca sativa L.) grown on soil enriched with spent coffee grounds

    OpenAIRE

    Cruz, Rebeca; Baptista, Paula; Cunha, Sara; Pereira, J.A.; Casal, Susana

    2012-01-01

    The impact of spent coffee grounds on carotenoid and chlorophyll content in lettuce (Lactuca sativa L. var. capitata) was evaluated. A greenhouse pot experiment was conducted with spent coffee amounts ranging from 0% to 20% (v/v). All evaluated pigments increased proportionally to spent coffee amounts. Lutein and β-carotene levels increased up to 90% and 72%, respectively, while chlorophylls increased up to 61%. Biomass was also improved in the presence of 2.5% to 10% spent coffee, decreasing...

  20. Peculiarities of the formation of lettuce (Lactuca sativa L.) varieties collection with reference characteristics

    OpenAIRE

    Н. В. Лещук

    2014-01-01

    Peculiarities of the formation of the collection of lettuce (Lactuca sativa L.) varieties with reference characteristics are considered. Methodological requirements for the formation, grouping, maintenance, use and updating of the examples varieties collection for identifi cation of all lettuce varieties were scientifi cally grounded. Varieties with relevant morphological characteristics and notes of their expressions for vegetative and generative organs of lettuce plants were identifi ed. Th...

  1. Effects of Lactuca sativa extract on exploratory behavior pattern, locomotor activity and anxiety in mice

    Directory of Open Access Journals (Sweden)

    S.N. Harsha

    2012-05-01

    Full Text Available Objective: To evaluate antianxiety property of Lactuca sativa, an important and commonly used leafy vegetable known for its medicinal properties belongs to Asteraceae family. Methods: Elevated plus maze (EPM, open field test (OFT, rat exposure test, hyponeophagia and marble burying test were performed in mice models to assess the exploratory behaviour and to assess anxiolytic property of hydro-alcohol extract of Lactuca sativa. Diazepam (1 mg/kg body wt. served as the standard anxiolytic agent for all the tests. The dried extract of the plant leaf in doses of 100, 200 and 400 mg/kg body weight was administered orally to mice for duration of 15 or 30 days and evaluated exploratory behaviour, locomotor and anxiolytic activities. Results: Time spent and number of entries into the open arm was measured in EPM followed by total locomotor activity in OFT and latency to enter the food zone in hyponeophagia. Conclusions: The study suggested that hydro-alcohol extract of Lactuca sativa leaves possess potent anxiolytic property.

  2. Produtividade das culturas de alface e rabanete em função da época de estabelecimento do consórcio

    OpenAIRE

    Cecilio Filho,Arthur Bernardes; May,André

    2002-01-01

    Avaliou-se a produtividade das culturas de rabanete e alface, e a qualidade de seus produtos, em função da época de estabelecimento do consórcio, na UNESP em Jaboticabal, de março a maio de 1999. Os tratamentos foram constituídos por consórcios estabelecidos aos 0; 7 e 14 dias após o transplantio (DAT) da alface e monocultivos implantados nestas mesmas épocas. As cultivares de rabanete (Raphanus sativus L.) e alface (Lactuca sativa L.) utilizadas foram, respectivamente, Crimson Gigante e Caro...

  3. Phyotoxicity of diesel soil contamination on the germination of Lactuca sativa and Ipomoea batatas.

    Science.gov (United States)

    Fatokun, Kayode; Lewu, Francis Bayo; Zharare, Godfrey Elijah

    2015-11-01

    Phytotoxic effect of diesel contaminated soil on germination rate of Lactuca sativa and Ipomoea batatas, at two concentrations ranges (0-6ml and 0-30ml), were investigated and compared. Diesel soil contamination was simulated and soil samples were taken from contaminated soil at 1, 5,10, 15, 25, 50, 75 and 100 days should be after planting. The result showed that in both plant species, diesel inhibited germination in a concentration dependent manner, Also, the influence of diesel contamination diminished with increased time duration; suggesting possible reduction in diesel toxicity over time. However, germination of lettuce was significant and negatively correlated (r2 = -0.941) with diesel contamination as compared to sweet potato (r2 = -0.638).Critical concentration of diesel in relation to seed germination of L. sativa was lower than vegetative germination of I. batatas, indicating that germination of I. batatas was less sensitive to diesel contamination as compared to L. sativa.

  4. Evapotranspiração da cultura da alface dentro e fora de ambiente protegido

    OpenAIRE

    Montes, David Rolando Palomino

    2008-01-01

    O trabalho foi conduzido na Área Experimental de Irrigação e Drenagem do Departamento de Engenharia Agrícola da Universidade Federal de Viçosa (UFV), de dezembro de 2007 e a janeiro de 2008, cultivando-se alface (Lactuca sativa L.), variedade Regina, em dois ambientes: dentro e fora de uma casa de vegetação, com objetivos de a) determinar a evapotranspiração da cultura (ETc) da alface, b) determinar o coeficiente de ajuste do irrigâmetro modificado (Ki) para os três primeiros estádios de dese...

  5. Blue and Green Light-Induced Phototropism in Arabidopsis thaliana and Lactuca sativa L. Seedlings 1

    Science.gov (United States)

    Steinitz, Benjamin; Ren, Zhangling; Poff, Kenneth L.

    1985-01-01

    Exposure time-response curves for blue and green light-induced phototropic bending in hypocotyls of Arabidopsis thaliana (L.) Heynh. and Lactuca sativa L. seedlings are presented. These seedlings show significant phototropic sensitivity up to 540 to 550 nanometers. Since wave-lengths longer than 560 nanometers do not induce phototropic bending, it is suggested that the response to 510 to 550 nanometers light is mediated by the specific blue light photoreceptor of phototropism. We advise care in the use of green `safelights' for studies of phototropism. PMID:16664021

  6. Allelopathic effect of Raphanus sativus on Urochloa decumbens and Lactuca sativa = Efeito alelopático de Raphanus sativus em Urochloa decumbens e Lactuca sativa

    Directory of Open Access Journals (Sweden)

    Rafael Navas

    2016-10-01

    Full Text Available The aim of this study was to evaluate the allelopathic potential of an extract from the leaves and roots of Raphanus sativus, on the species Urochloa decumbens and Lactuca sativa L. To obtain the extract, the leaves and roots of R. sativus were used separately, crushed at a proportion of 200 g of leaves to 1 L of water to give a crude aqueous extract (100%. Dilutions of 60%, 40% and 20%, and the control were produced from this extract. Seeds of U. decumbens and L. sativa were evenly distributed over two sheets of germitest paper, with four replications of 40 seeds each. Germination was evaluated at 7 and 14 days after sowing, together with the germination speed index (GSI, length of the shoots and roots, and dry weight. The design was completely randomised, and the values submitted to analysis of variance by F-test and regression analysis. The leaf extract gave a reduction in the germination of L. sativa at all tested doses. With application of the root extract, an increase was seen in germination, in the GSI and length of the radicle in U. decumbens at doses of from 40%. Moreover, with application of the leaf extract, the length of the shoot and radicle were also greater, irrespective of the dose applied. There was no effect from the treatments on the dry mass of the species. = Objetivou-se com este trabalho avaliar o potencial alelopático de extrato de folhas e raízes de Raphanus sativus, nas espécies Urochloa decumbens e Lactuca sativa L. Para obtenção do extrato, foram utilizadas separadamente folhas e raízes de R. sativus, trituradas na proporção de 200 g de folhas para 1 L de água, resultando no extrato aquoso bruto (100%. A partir desse extrato, foram realizadas as diluições de 60%, 40% e 20% e testemunha. Sementes de U. decumbens e L. sativa foram distribuídas uniformemente sobre duas folhas de papel germitest, com quatro repetições, com 40 sementes cada. As avaliações de germinação foram realizadas aos 7 e aos 14 dias

  7. Development of genomic SSR markers for fingerprinting lettuce (Lactuca sativa L. cultivars and mapping genes

    Directory of Open Access Journals (Sweden)

    Rauscher Gilda

    2013-01-01

    Full Text Available Abstract Background Lettuce (Lactuca sativa L. is the major crop from the group of leafy vegetables. Several types of molecular markers were developed that are effectively used in lettuce breeding and genetic studies. However only a very limited number of microsattelite-based markers are publicly available. We have employed the method of enriched microsatellite libraries to develop 97 genomic SSR markers. Results Testing of newly developed markers on a set of 36 Lactuca accession (33 L. sativa, and one of each L. serriola L., L. saligna L., and L. virosa L. revealed that both the genetic heterozygosity (UHe = 0.56 and the number of loci per SSR (Na = 5.50 are significantly higher for genomic SSR markers than for previously developed EST-based SSR markers (UHe = 0.32, Na = 3.56. Fifty-four genomic SSR markers were placed on the molecular linkage map of lettuce. Distribution of markers in the genome appeared to be random, with the exception of possible cluster on linkage group 6. Any combination of 32 genomic SSRs was able to distinguish genotypes of all 36 accessions. Fourteen of newly developed SSR markers originate from fragments with high sequence similarity to resistance gene candidates (RGCs and RGC pseudogenes. Analysis of molecular variance (AMOVA of L. sativa accessions showed that approximately 3% of genetic diversity was within accessions, 79% among accessions, and 18% among horticultural types. Conclusions The newly developed genomic SSR markers were added to the pool of previously developed EST-SSRs markers. These two types of SSR-based markers provide useful tools for lettuce cultivar fingerprinting, development of integrated molecular linkage maps, and mapping of genes.

  8. Development of genomic SSR markers for fingerprinting lettuce (Lactuca sativa L.) cultivars and mapping genes.

    Science.gov (United States)

    Rauscher, Gilda; Simko, Ivan

    2013-01-22

    Lettuce (Lactuca sativa L.) is the major crop from the group of leafy vegetables. Several types of molecular markers were developed that are effectively used in lettuce breeding and genetic studies. However only a very limited number of microsattelite-based markers are publicly available. We have employed the method of enriched microsatellite libraries to develop 97 genomic SSR markers. Testing of newly developed markers on a set of 36 Lactuca accession (33 L. sativa, and one of each L. serriola L., L. saligna L., and L. virosa L.) revealed that both the genetic heterozygosity (UHe = 0.56) and the number of loci per SSR (Na = 5.50) are significantly higher for genomic SSR markers than for previously developed EST-based SSR markers (UHe = 0.32, Na = 3.56). Fifty-four genomic SSR markers were placed on the molecular linkage map of lettuce. Distribution of markers in the genome appeared to be random, with the exception of possible cluster on linkage group 6. Any combination of 32 genomic SSRs was able to distinguish genotypes of all 36 accessions. Fourteen of newly developed SSR markers originate from fragments with high sequence similarity to resistance gene candidates (RGCs) and RGC pseudogenes. Analysis of molecular variance (AMOVA) of L. sativa accessions showed that approximately 3% of genetic diversity was within accessions, 79% among accessions, and 18% among horticultural types. The newly developed genomic SSR markers were added to the pool of previously developed EST-SSRs markers. These two types of SSR-based markers provide useful tools for lettuce cultivar fingerprinting, development of integrated molecular linkage maps, and mapping of genes.

  9. Allelopathic and bioherbicidal potential of Cladonia verticillaris on the germination and growth of Lactuca sativa.

    Science.gov (United States)

    Tigre, R C; Silva, N H; Santos, M G; Honda, N K; Falcão, E P S; Pereira, E C

    2012-10-01

    Responses to germination and initial growth of Lactuca sativa (lettuce) submitted to organic extracts and purified compounds of Cladonia verticillaris ("salambaia") were analyzed in this work. The experiments were conducted in laboratory conditions using extracts and pure compounds at different concentrations. None of the assays showed any influence on the germination of L. sativa seeds using C. verticillaris extracts; however, modifications in leaf area and seedling hypocotyl and root development occurred. In the growth experiments, seedlings exposed to ether or acetone extract showed diminished hypocotyl growth in detriment to the root stimulus, compared to controls. Increases in extract concentrations led to the formation of abnormal seedlings. To determine the allelochemicals of C. verticillaris, its principal components, fumarprotocetraric and protocetraric acids, were isolated and then analyzed by high performance liquid chromatography (HPLC). When the seedlings were exposed to the two acids separately, presented increased leaf area at all concentrations. In contrast, hypocotyl and root stimulus was observed only in the presence of protocetraric acid at different concentrations. Fumarprotocetraric as well as protocetraric acids, isolated and purified from C. verticillaris and Parmotrema dilatatum respectively, influenced the development of L. sativa seedlings at high concentrations, indicating a possible bioherbicide potential of these acids. Crown Copyright © 2012. Published by Elsevier Inc. All rights reserved.

  10. Performance and feeding behaviour of two biotypes of the black currant-lettuce aphid, Nasonovia ribisnigri, on resistant and susceptible Lactuca sativa near-isogenic lines

    NARCIS (Netherlands)

    Broeke, ten C.J.M.; Dicke, M.; Loon, van J.J.A.

    2013-01-01

    The black currant-lettuce aphid, Nasonovia ribisnigri, is an important pest of cultivated lettuce, Lactuca sativa. Since 1982, the control of this aphid on lettuce is largely based on host plant resistance, conferred by the Nr gene, introgressed from Lactuca virosa. The resistance mechanism remains

  11. Toxic effects of copper-based nanoparticles or compounds to lettuce (Lactuca sativa) and alfalfa (Medicago sativa).

    Science.gov (United States)

    Hong, Jie; Rico, Cyren M; Zhao, Lijuan; Adeleye, Adeyemi S; Keller, Arturo A; Peralta-Videa, Jose R; Gardea-Torresdey, Jorge L

    2015-01-01

    The increased production and use of nanoparticles (NPs) has generated concerns about their impact on living organisms. In this study, nCu, bulk Cu, nCuO, bulk CuO, Cu(OH)2 (CuPRO 2005, Kocide 3000), and CuCl2 were exposed for 15 days to 10 days-old hydroponically grown lettuce (Lactuca sativa) and alfalfa (Medicago sativa). Each compound was applied at 0, 5, 10, and 20 mg L(-1). At harvest, we measured the size of the plants and determined the concentration of Cu, macro and microelements by using ICP-OES. Catalase and ascorbate peroxidase activity was also determined. Results showed that all Cu NPs/compounds reduced the root length by 49% in both plant species. All Cu NPs/compounds increased Cu, P, and S (>100%, >50%, and >20%, respectively) in alfalfa shoots and decreased P and Fe in lettuce shoot (>50% and >50%, respectively, excluding Fe in CuCl2 treatment). Biochemical assays showed reduced catalase activity in alfalfa (root and shoot) and increased ascorbate peroxidase activity in roots of both plant species. Results suggest that Cu NPs/compounds not only reduced the size of the plants but altered nutrient content and enzyme activity in both plant species.

  12. Transfer and expression of the rabbit defensin NP-1 gene in lettuce (Lactuca sativa).

    Science.gov (United States)

    Song, D; Xiong, X; Tu, W F; Yao, W; Liang, H W; Chen, F J; He, Z Q

    2017-01-23

    Lettuce (Lactuca sativa L.) is an annual plant of the daisy family, Asteraceae, with high food and medicinal value. However, the crop is susceptible to several viruses that are transmitted by aphids and is highly vulnerable to post-harvest diseases, as well as insect and mammal pests and fungal and bacterial diseases. Here, the rabbit defensin gene NP-1 was transferred into lettuce by Agrobacterium-mediated transformation to obtain a broad-spectrum disease-resistant lettuce. Transgenic lettuce plants were selected and regenerated on selective media. The presence of the NP-1 gene in these plants was confirmed by western blot analyses. Resistance tests revealed native defensin NP-1 expression conferred partial resistance to Bacillus subtilis and Pseudomonas aeruginosa, which suggests new possibilities for lettuce disease resistance.

  13. Growth promotion of Lactuca sativa in response to volatile organic compounds emitted from diverse bacterial species.

    Science.gov (United States)

    Fincheira, Paola; Venthur, Herbert; Mutis, Ana; Parada, Maribel; Quiroz, Andrés

    2016-12-01

    Agrochemicals are currently used in horticulture to increase crop production. Nevertheless, their indiscriminate use is a relevant issue for environmental and legal aspects. Alternative tools for reducing fertilizers and synthetic phytohormones are being investigated, such as the use of volatile organic compounds (VOCs) as growth inducers. Some soil bacteria, such as Pseudomonas and Bacillus, stimulate Arabidopsis and tobacco growth by releasing VOCs, but their effects on vegetables have not been investigated. Lactuca sativa was used as model vegetable to investigate bacterial VOCs as growth inducers. We selected 10 bacteria strains, belonging to Bacillus, Staphylococcus and Serratia genera that are able to produce 3-hydroxy-2-butanone (acetoin), a compound with proven growth promoting activity. Two-day old-seedlings of L. sativa were exposed to VOCs emitted by the selected bacteria grown in different media cultures for 7 days. The results showed that the VOCs released from the bacteria elicited an increase in the number of lateral roots, dry weight, root growth and shoot length, depending on the media used. Three Bacillus strains, BCT53, BCT9 and BCT4, were selected according to its their growth inducing capacity. The BCT9 strain elicited the greatest increases in dry weight and primary root length when L. sativa seedlings were subjected to a 10-day experiment. Finally, because acetoin only stimulated root growth, we suggest that other volatiles could be responsible for the growth promotion of L. sativa. In conclusion, our results strongly suggest that bacteria volatiles can be used as growth-inducers as alternative or complementary strategies for application in horticulture species. Copyright © 2016 Elsevier GmbH. All rights reserved.

  14. Volatiles emitted by Bacillus sp. BCT9 act as growth modulating agents on Lactuca sativa seedlings.

    Science.gov (United States)

    Fincheira, Paola; Parra, Leonardo; Mutis, Ana; Parada, Maribel; Quiroz, Andrés

    2017-10-01

    Chemical products are applied during horticulture to increase food production, but the environmental problems resulting from these applications have led to a search for more sustainable products. Volatile organic compounds (VOCs) demonstrating plant growth promoter (PGP) activity released by bacterial species have emerged as alternatives, but their effects on Lactuca sativa growth are unknown. In this study, VOCs released by Bacillus sp. BCT9 cultures grown in different media (Methyl Red & Voges Proskauer, Murashige & Skoog and nutrient media) at concentrations of 0.1, 0.2, 0.5 and 0.7 (measured as the absorbance, λ=600nm) were tested to evaluate their activity as growth inducers of L. sativa after 10days of exposure. Lower concentrations of BCT9 increased root length, and higher concentrations induced shoot length and lateral root length. The dry weight and number of lateral roots increased similarly, independent of concentration, for VOCs produced in all culture media. BCT9 cultures grown in Methyl Red & Voges Proskauer medium as bioactive compounds with or without lanolin. These VOCs increased shoot length, root length and dry weight at low concentrations, independent of the presence of lanolin. Lateral root length increased with the application of 2-nonanone (50ppm) and 2-undecanone (0.05ppm). Based on these results, the use of bioactive volatiles as growth inducers of horticultural species represents an alternative or complementary strategy. Copyright © 2017 Elsevier GmbH. All rights reserved.

  15. Internalization of Murine Norovirus 1 by Lactuca sativa during Irrigation ▿

    Science.gov (United States)

    Wei, Jie; Jin, Yan; Sims, Tom; Kniel, Kalmia E.

    2011-01-01

    Romaine lettuce (Lactuca sativa) was grown hydroponically or in soil and challenged with murine norovirus 1 (MNV) under two conditions: one mimicking a severe one-time contamination event and another mimicking a lower level of contamination occurring over time. In each condition, lettuce was challenged with MNV delivered at the roots. In the first case, contamination occurred on day one with 5 × 108 reverse transcriptase quantitative PCR (RT-qPCR) U/ml MNV in nutrient buffer, and irrigation water was replaced with virus-free buffer every day for another 4 days. In the second case, contamination with 5 × 105 RT-qPCR U/ml MNV (freshly prepared) occurred every day for 5 days. Virus had a tendency to adsorb to soil particles, with a small portion suspended in nutrient buffer; e.g., ∼8 log RT-qPCR U/g MNV was detected in soil during 5 days of challenge with virus inoculums of 5 × 108 RT-qPCR U/ml at day one, but sativa. PMID:21296944

  16. Phytohormone profile in Lactuca sativa and Brassica oleracea plants grown under Zn deficiency.

    Science.gov (United States)

    Navarro-León, Eloy; Albacete, Alfonso; Torre-González, Alejandro de la; Ruiz, Juan M; Blasco, Begoña

    2016-10-01

    Phytohormones, structurally diverse compounds, are involved in multiple processes within plants, such as controlling plant growth and stress response. Zn is an essential micronutrient for plants and its deficiency causes large economic losses in crops. Therefore, the purpose of this study was to analyse the role of phytohormones in the Zn-deficiency response of two economically important species, i.e. Lactuca sativa and Brassica oleracea. For this, these two species were grown hydroponically with different Zn-application rates: 10 μM Zn as control and 0.1 μM Zn as deficiency treatment and phytohormone concentration was determined by U-HPLC-MS. Zn deficiency resulted in a substantial loss of biomass in L. sativa plants that was correlated with a decline in growth-promoting hormones such as indole-3-acetic acid (IAA), cytokinins (CKs), and gibberellins (GAs). However these hormones increased or stabilized their concentrations in B. oleracea and could help to maintain the biomass in this species. A lower concentration of stress-signaling hormones such as ethylene precursor aminocyclopropane-1-carboxylic acid (ACC), abscisic acid (ABA), salicylic acid (SA) and jasmonic acid (JA) and also CKs might be involved in Zn uptake in L. sativa while a rise in GA4, isopentenyl adenine (iP), and ACC and a fall in JA and SA might contribute to a better Zn-utilization efficiency (ZnUtE), as observed in B. oleracea plants. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Elucidating the genetic basis of antioxidant status in lettuce (Lactuca sativa).

    Science.gov (United States)

    Damerum, Annabelle; Selmes, Stacey L; Biggi, Gaia F; Clarkson, Graham Jj; Rothwell, Steve D; Truco, Maria José; Michelmore, Richard W; Hancock, Robert D; Shellcock, Connie; Chapman, Mark A; Taylor, Gail

    2015-01-01

    A diet rich in phytonutrients from fruit and vegetables has been acknowledged to afford protection against a range of human diseases, but many of the most popular vegetables are low in phytonutrients. Wild relatives of crops may contain allelic variation for genes determining the concentrations of these beneficial phytonutrients, and therefore understanding the genetic basis of this variation is important for breeding efforts to enhance nutritional quality. In this study, lettuce recombinant inbred lines, generated from a cross between wild and cultivated lettuce (Lactuca serriola and Lactuca sativa, respectively), were analysed for antioxidant (AO) potential and important phytonutrients including carotenoids, chlorophyll and phenolic compounds. When grown in two environments, 96 quantitative trait loci (QTL) were identified for these nutritional traits: 4 for AO potential, 2 for carotenoid content, 3 for total chlorophyll content and 87 for individual phenolic compounds (two per compound on average). Most often, the L. serriola alleles conferred an increase in total AOs and metabolites. Candidate genes underlying these QTL were identified by BLASTn searches; in several cases, these had functions suggesting involvement in phytonutrient biosynthetic pathways. Analysis of a QTL on linkage group 3, which accounted for >30% of the variation in AO potential, revealed several candidate genes encoding multiple MYB transcription factors which regulate flavonoid biosynthesis and flavanone 3-hydroxylase, an enzyme involved in the biosynthesis of the flavonoids quercetin and kaempferol, which are known to have powerful AO activity. Follow-up quantitative RT-PCR of these candidates revealed that 5 out of 10 genes investigated were significantly differentially expressed between the wild and cultivated parents, providing further evidence of their potential involvement in determining the contrasting phenotypes. These results offer exciting opportunities to improve the nutritional

  18. A rapid and efficient in vitro regeneration system for lettuce (Lactuca sativa L.).

    Science.gov (United States)

    Armas, Isabel; Pogrebnyak, Natalia; Raskin, Ilya

    2017-01-01

    Successful biotechnological improvement of crop plants requires a reliable and efficient in vitro regeneration system. Lettuce ( Lactuca sativa L.), one the most important vegetable crops worldwide, is strongly genotype-dependent in terms of regeneration capacity, limiting the potential for biotechnological improvement of cultivars which show recalcitrance under currently available protocols. The effect of different nutrient sources, plant hormone combinations and activated charcoal supplementation on shoot induction efficiency was evaluated on the cultivar 'RSL NFR', which had previously shown poor regeneration efficiency. Multiple shoot organogenesis from cotyledon explants was recorded at the highest frequency and speed on Murashige and Skoog regeneration medium supplemented with 200 mg/l of activated charcoal, 3% sucrose, 10 mg/l benzylaminopurine and 0.5 mg/l naphthaleneacetic acid, which induced shoots through direct regeneration in 90.8 ± 7.9% of explants. High shoot induction efficiency was also observed, albeit not quantified, when using this medium on some other cultivars. This activated charcoal-containing regeneration medium might offer a rapid and efficient option for direct shoot induction in some lettuce genotypes that do not respond well to common lettuce regeneration protocols. This is also the first report of the effect of activated charcoal in lettuce tissue culture.

  19. Ecotoxicological impact of two soil remediation treatments in Lactuca sativa seeds.

    Science.gov (United States)

    Rede, Diana; Santos, Lúcia H M L M; Ramos, Sandra; Oliva-Teles, Filipe; Antão, Cristina; Sousa, Susana R; Delerue-Matos, Cristina

    2016-09-01

    Pharmaceuticals have been identified as environmental emerging pollutants and are present in different compartments, including soils. Chemical remediation showed to be a good and suitable approach for soil remediation, though the knowledge in their impact for terrestrial organisms is still limited. Therefore, in this work, two different chemical remediation treatments (Fenton oxidation and nanoremediation) were applied to a soil contaminated with an environmental representative concentration of ibuprofen (3 ng g(-1)). The phytotoxic impact of a traditional soil remediation treatment (Fenton oxidation) and of a new and more sustainable approach for soil remediation (nanoremediation using green nano-scale zero-valent iron nanoparticles (nZVIs)) was evaluated in Lactuca sativa seeds. Percentage of seed germination, root elongation, shoot length and leaf length were considered as endpoints to assess the possible acute phytotoxicity of the soil remediation treatments as well as of the ibuprofen contaminated soil. Both chemical remediation treatments showed to have a negative impact in the germination and development of lettuce seeds, exhibiting a reduction up to 45% in the percentage of seed germination and a decrease around 80% in root elongation comparatively to the contaminated soil. These results indicate that chemical soil remediation treatments could be more prejudicial for terrestrial organisms than contaminated soils. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Semi-High Throughput Screening for Potential Drought-tolerance in Lettuce (Lactuca sativa) Germplasm Collections.

    Science.gov (United States)

    Knepper, Caleb; Mou, Beiquan

    2015-04-17

    This protocol describes a method by which a large collection of the leafy green vegetable lettuce (Lactuca sativa L.) germplasm was screened for likely drought-tolerance traits. Fresh water availability for agricultural use is a growing concern across the United States as well as many regions of the world. Short-term drought events along with regulatory intervention in the regulation of water availability coupled with the looming threat of long-term climate shifts that may lead to reduced precipitation in many important agricultural regions has increased the need to hasten the development of crops adapted for improved water use efficiency in order to maintain or expand production in the coming years. This protocol is not meant as a step-by-step guide to identifying at either the physiological or molecular level drought-tolerance traits in lettuce, but rather is a method developed and refined through the screening of thousands of different lettuce varieties. The nature of this screen is based in part on the streamlined measurements focusing on only three water-stress indicators: leaf relative water content, wilt, and differential plant growth following drought-stress. The purpose of rapidly screening a large germplasm collection is to narrow the candidate pool to a point in which more intensive physiological, molecular, and genetic methods can be applied to identify specific drought-tolerant traits in either the lab or field. Candidates can also be directly incorporated into breeding programs as a source of drought-tolerance traits.

  1. Carotenoids of Lettuce (Lactuca sativa L. Grown on Soil Enriched with Spent Coffee Grounds

    Directory of Open Access Journals (Sweden)

    Susana Casal

    2012-02-01

    Full Text Available The impact of spent coffee grounds on carotenoid and chlorophyll content in lettuce (Lactuca sativa L. var. capitata was evaluated. A greenhouse pot experiment was conducted with spent coffee amounts ranging from 0% to 20% (v/v. All evaluated pigments increased proportionally to spent coffee amounts. Lutein and β-carotene levels increased up to 90% and 72%, respectively, while chlorophylls increased up to 61%. Biomass was also improved in the presence of 2.5% to 10% spent coffee, decreasing for higher amounts. Nevertheless, all plants were characterized by lower organic nitrogen content than the control ones, inversely to the spent coffee amounts, pointing to possible induced stress. Collected data suggests that plants nutritional features, with regards to these bioactive compounds, can be improved by the presence of low amounts of spent coffee grounds (up to 10%. This observation is particularly important because soil amendment with spent coffee grounds is becoming increasingly common within domestic agriculture. Still, further studies on the detailed influence of spent coffee bioactive compounds are mandatory, particularly regarding caffeine.

  2. Carotenoids of lettuce (Lactuca sativa L.) grown on soil enriched with spent coffee grounds.

    Science.gov (United States)

    Cruz, Rebeca; Baptista, Paula; Cunha, Sara; Pereira, José Alberto; Casal, Susana

    2012-02-07

    The impact of spent coffee grounds on carotenoid and chlorophyll content in lettuce (Lactuca sativa L. var. capitata) was evaluated. A greenhouse pot experiment was conducted with spent coffee amounts ranging from 0% to 20% (v/v). All evaluated pigments increased proportionally to spent coffee amounts. Lutein and β-carotene levels increased up to 90% and 72%, respectively, while chlorophylls increased up to 61%. Biomass was also improved in the presence of 2.5% to 10% spent coffee, decreasing for higher amounts. Nevertheless, all plants were characterized by lower organic nitrogen content than the control ones, inversely to the spent coffee amounts, pointing to possible induced stress. Collected data suggests that plants nutritional features, with regards to these bioactive compounds, can be improved by the presence of low amounts of spent coffee grounds (up to 10%). This observation is particularly important because soil amendment with spent coffee grounds is becoming increasingly common within domestic agriculture. Still, further studies on the detailed influence of spent coffee bioactive compounds are mandatory, particularly regarding caffeine.

  3. The Influence of biol in the crop yield of Lactuca sativa L. variety Iceberg

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    Pomboza-Tamaquiza Pablo

    2016-11-01

    Full Text Available The objective of the research was to assess the influence of biol enriched with efficient micro-organisms, in the ecological cultivation of Lactuca sativa L (lettuce variety "Iceberg". The field test was carried out on the farm of Querochaca, Faculty of Sciences Agriculture, of the Technical University of Ambato. The studied factors were doses of biol (2%, 4% and 6% and frequencies of application (8 and 15 days, I know used the experimental design of complete blocks at random, with factorial arrangement of 3x2 1 with three repetitions. We evaluated: plant height, diameter of the main stem, days to harvest, weight and diameter of the bud commercial, performance in kg/plot neta and performance in kg/experimental unit, conducted the significance test of Duncan to 5%. The results showed that the dose of 6 per cent applied every 15 days treatment D3F2, contributed to the larger diameter of the bud commercial (25.9 cm; the greater weight of cogollo commercial (1.14 kg and the higher performance (549 kg/experimental unit. This suggests that the implementation of biol can be an important ecological alternative to fertilize organic farming as the lettuce by reducing the use of fertilizers in chemical synthesis and production costs.

  4. Differential Responses of Two Lactuca sativa Varieties to Bicarbonate-Induced Iron Deficiency

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    Mohamed Chebbi

    2013-11-01

    Full Text Available Iron chlorosis induced by bicarbonate is very common in calcareous soils, where bicarbonate (HCO3- ions are present at high concentrations. In this study, morpho-physiological and biochemical responses of two Lactuca sativa varieties (Romaine and Vista to bicarbonate induced iron deficiency were investigated. The culture was conducted on nutrient solution containing 5 µM Fe and 10 mM NaHCO3, in a growth chamber with controlled conditions. After 14 days of bicarbonate treatment, the two varieties seedling showed a slight yellowing of young leaves associated with a significant decline of plant biomass, leaf number and area. Furthermore, the concentrations of the nutrient elements (potassium, magnesium, iron and calcium in leaves and roots of two lettuce varieties were modified. In roots of bicarbonate treated plants, the Fe-chelate reductase activity was increased as compared to control in both varieties. PEPC activity was enhanced only in Vista variety. Moreover, Fe deficiency induced a small change in the photosynthetic parameters and chlorophyll fluorescence, especially in Romaine variety. These changes are accompanied by decreases in ribulose 1.5-bisphosphate carboxylase/oxygenase (Rubisco activity. These findings indicated that Vista variety could survive at low iron supply.

  5. Evaluation of response of lettuce (Lactuca sativa L. to temperature and light stress

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    Nidal Tabit Shaban

    2016-06-01

    Full Text Available The aim of the study was to assess the effect of irrigation water temperature and shading on the rate of photosynthesis and transpiration in four varieties of lettuce (Lactuca sativa L. – green foliage (‘Salakis’ and ‘Estony’ and red foliage (‘Lollo Rossa’ and ‘Nika’. During the production of seedlings in the greenhouse, two irrigation water temperature regimes (12 and 20°C were applied. After transplanting in the field plants were grown under three lighting systems (100, 70, and 50% of lighting in the open. The rates of photosynthesis and transpiration were measured at the end of the greenhouse period and 14 days after shading in the field using a Li 6400 infrared gas analyzer. In most varieties, cooling of the irrigation water was not found to have an effect on the rate of photosynthesis. Plants of all the varieties responded to the decrease in irrigation water temperature and to strong shading by reducing transpiration and increasing the water use efficiency. The ‘Salakis’ and ‘Estony’ plants have shown the best adaptability to the changing conditions and therefore they could be used successfully in the practice of extending vegetative growth.

  6. Combination of minimal processing and irradiation to improve the microbiological safety of lettuce ( Lactuca sativa, L.)

    Science.gov (United States)

    Goularte, L.; Martins, C. G.; Morales-Aizpurúa, I. C.; Destro, M. T.; Franco, B. D. G. M.; Vizeu, D. M.; Hutzler, B. W.; Landgraf, M.

    2004-09-01

    The feasibility of gamma radiation in combination with minimal processing (MP) to reduce the number of Salmonella spp. and Escherichia coli O157:H7 in iceberg lettuce ( Lactuca sativa, L.) (shredded) was studied in order to increase the safety of the product. The reduction of the microbial population during the processing, the D10-values for Salmonella spp. and E. coli O157:H7 inoculated on shredded iceberg lettuce as well as the sensory evaluation of the irradiated product were evaluated. The immersion in chlorine (200 ppm) reduced coliform and aerobic mesophilic microorganisms by 0.9 and 2.7 log, respectively. D-values varied from 0.16 to 0.23 kGy for Salmonella spp. and from 0.11 to 0.12 kGy for E. coli O157:H7. Minimally processed iceberg lettuce exposed to 0.9 kGy does not show any change in sensory attributes. However, the texture of the vegetable was affected during the exposition to 1.1 kGy. The exposition of MP iceberg lettuce to 0.7 kGy reduced the population of Salmonella spp. by 4.0 log and E. coli by 6.8 log without impairing the sensory attributes. The combination of minimal process and gamma radiation to improve the safety of iceberg lettuce is feasible if good hygiene practices begins at farm stage.

  7. Efficient and stable transformation of Lactuca sativa L. cv. Cisco (lettuce) plastids.

    Science.gov (United States)

    Kanamoto, Hirosuke; Yamashita, Atsushi; Asao, Hiroshi; Okumura, Satoru; Takase, Hisabumi; Hattori, Masahira; Yokota, Akiho; Tomizawa, Ken-Ichi

    2006-04-01

    Transgenic plastids offer unique advantages in plant biotechnology, including high-level foreign protein expression. However, broad application of plastid genome engineering in biotechnology has been largely hampered by the lack of plastid transformation systems for major crops. Here we describe the development of a plastid transformation system for lettuce, Lactuca sativa L. cv. Cisco. The transforming DNA carries a spectinomycin-resistance gene (aadA) under the control of lettuce chloroplast regulatory expression elements, flanked by two adjacent lettuce plastid genome sequences allowing its targeted insertion between the rbcL and accD genes. On average, we obtained 1 transplastomic lettuce plant per bombardment. We show that lettuce leaf chloroplasts can express transgene-encoded GFP to approximately 36% of the total soluble protein. All transplastomic T0 plants were fertile and the T1 progeny uniformly showed stability of the transgene in the chloroplast genome. This system will open up new possibilities for the efficient production of edible vaccines, pharmaceuticals, and antibodies in plants.

  8. Rhizobacteria Pseudomonas fluorescens and Azospirillum sp. association enhances growth of Lactuca sativa L. under tropical conditions

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    Amael APONTE

    2017-06-01

    Full Text Available The selection of microorganisms that enhance plant growth and confer biotic and abiotic tolerance to crops constitutes a biotechnology currently gaining importance on a global scale. The aim of this investigation was to evaluate the effects of inoculating rhizobacteria to lettuce (Lactuca sativa L. on seed germination and vegetative development in order to use isolates as potential biofertilizers under tropical conditions. Five isolates of Pseudomonas fluorescens (Pf and one of Azospirillum sp. (Az were inoculated to seeds using a bacterial suspension of 1.5*108 CFU*mL-1. In vitro, none of the isolates promoted germination. In vivo, isolates promoted growth and acted as stress alleviators by conferring tolerance to high temperatures (≥ 30 °C. The highest seedling emergence percentages were induced by the association of P.fluorescens with Azospirillum. This association also promoted the highest leaf-area in 25 d seedlings and exhibited a significantly higher dry-weight in 40 d plants compared to the control (P≤0.05 supporting the advantages of bio-consortiums over individual strains. The strains were able to produce dependent L-tryptophan indole-3-acetic acid (IAA, to solubilize phosphorous in vitro and tolerated at least 5%-salt stress. The results indicate that isolate Pf (26 and Az possess plant growth promoting rhizobacteria (PGPR traits and should be further assessed. This study suggests that P. fluorescens and Azospirillum act synergically and are able to trigger an induced-tolerance mechanism in lettuce under abiotic stress.

  9. Toxicity of polyfluorinated and perfluorinated compounds to lettuce (Lactuca sativa) and green algae (Pseudokirchneriella subcapitata).

    Science.gov (United States)

    Ding, Guanghui; Wouterse, Marja; Baerselman, Rob; Peijnenburg, Willie J G M

    2012-01-01

    Recently, polyfluorinated and perfluorinated compounds (PFCs) have been detected in most surface waters around the world. Because some PFCs are persistent and tend to accumulate in surface waters, their potential adverse effects to aquatic organisms have received increasing attention. Nevertheless, currently available toxicity information is limited. The aim of this study was to evaluate the toxicity effects of seven PFCs on root elongation of lettuce (Lactuca sativa) and photosynthesis of green algae (Pseudokirchneriella subcapitata). It was found that the toxicity profiles of both species tested were similar and had good relations with the fluorinated carbon-chain length of the PFCs investigated. One of the compounds tested, perfluorobutanoic acid, was found to be more toxic than expected in the algae test, which may be related with acidification of the test solution. It was concluded that because short-chained PFCs are becoming the predominant PFC pollutants in surface waters, their long-term toxicity and mixture toxicity with other PFCs should be studied in greater detail.

  10. Zn-biofortification enhanced nitrogen metabolism and photorespiration process in green leafy vegetable Lactuca sativa L.

    Science.gov (United States)

    Barrameda-Medina, Yurena; Lentini, Marco; Esposito, Sergio; Ruiz, Juan M; Blasco, Begoña

    2017-04-01

    Excessive rates of nitrogen (N) fertilizers may result in elevated concentrations of nitrate (NO 3 - ) in plants. Considering that many programs of biofortification with trace elements are being performed, it has become important to study how the application of these elements affects plant physiology and, particularly, N utilization in leaf crops. The main objective of the present study was to determine whether the NO 3 - accumulation and the nitrogen use efficiency was affected by the application of different doses of Zn in Lactuca sativa plants. Zn doses in the range 80-100 µmol L -1 produced an increase in Zn concentration provoking a decrease of NO 3 - concentration and increase of the nitrate reductase, glutamine synthetase and aspartate aminotransferase activities, as well as the photorespiration processes. As result, we observed an increase in reduced N, total N concentration and N utilization efficiency. Consequently, at a dose of 80 µmol L -1 of Zn, the amino acid concentration increased significantly. Adequate Zn fertilization is an important critical player in lettuce, especially at a dose of 80 µmol L -1 of Zn, because it could result in an increase in the Zn concentration, a reduction of NO 3 - levels and an increase the concentration of essential amino acids, with all of them having beneficial properties for the human diet. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  11. Combination of minimal processing and irradiation to improve the microbiological safety of lettuce (Lactuca sativa, L.)

    Energy Technology Data Exchange (ETDEWEB)

    Goularte, L.; Martins, C.G.; Morales-Aizpurua, I.C.; Destro, M.T.; Franco, B.D.G.M.; Vizeu, D.M.; Hutzler, B.W.; Landgraf, M. E-mail: landgraf@usp.br

    2004-10-01

    The feasibility of gamma radiation in combination with minimal processing (MP) to reduce the number of Salmonella spp. and Escherichia coli O157:H7 in iceberg lettuce (Lactuca sativa, L.) (shredded) was studied in order to increase the safety of the product. The reduction of the microbial population during the processing, the D{sub 10}-values for Salmonella spp. and E. coli O157:H7 inoculated on shredded iceberg lettuce as well as the sensory evaluation of the irradiated product were evaluated. The immersion in chlorine (200 ppm) reduced coliform and aerobic mesophilic microorganisms by 0.9 and 2.7 log, respectively. D-values varied from 0.16 to 0.23 kGy for Salmonella spp. and from 0.11 to 0.12 kGy for E. coli O157:H7. Minimally processed iceberg lettuce exposed to 0.9 kGy does not show any change in sensory attributes. However, the texture of the vegetable was affected during the exposition to 1.1 kGy. The exposition of MP iceberg lettuce to 0.7 kGy reduced the population of Salmonella spp. by 4.0 log and E. coli by 6.8 log without impairing the sensory attributes. The combination of minimal process and gamma radiation to improve the safety of iceberg lettuce is feasible if good hygiene practices begins at farm stage.

  12. Phytotoxicity of 15 common pharmaceuticals on the germination of Lactuca sativa and photosynthesis of Chlamydomonas reinhardtii.

    Science.gov (United States)

    Pino, Ma Rosa; Muñiz, Selene; Val, Jonatan; Navarro, Enrique

    2016-11-01

    Pharmaceuticals reach terrestrial environments through the application of treated wastewaters and biosolids to agricultural soils. We have investigated the toxicity of 15 common pharmaceuticals, classified as nonsteroidal anti-inflammatory drugs (NSAIDs), blood lipid-lowering agents, β-blockers and antibiotics, in two photosynthetic organisms. Twelve pharmaceuticals caused inhibitory effects on the radicle and hypocotyl elongation of Lactuca sativa seeds. The EC 50 values obtained were in the range of 170-5656 mg L -1 in the case of the radicle and 188-4558 mg L -1 for the hypocotyl. Propranolol was the most toxic drug for both root and hypocotyl elongation, followed by the NSAIDs, then gemfibrozil and tetracycline. Other effects, such as root necrosis, inhibition of root growth and curly hairs, were detected. However, even at the highest concentrations tested (3000 mg L -1 ), seed germination was not affected. NSAIDs decreased the photosynthetic yield of Chlamydomonas reinhardtii, but only salicylic acid showed EC 50 values below 1000 mg L -1 . The first effects detected at low concentrations, together with the concentrations found in environmental samples, indicate that the use of biosolids and wastewaters containing pharmaceuticals should be regulated and their compositions assessed in order to prevent medium- and long-term impacts on agricultural soils and crops.

  13. Assessment of genetic diversity in lettuce (Lactuca sativaL.) germplasm using RAPD markers.

    Science.gov (United States)

    Sharma, Shubhangi; Kumar, Pankaj; Gambhir, Geetika; Kumar, Ramesh; Srivastava, D K

    2018-01-01

    The importance of germplasm characterization is an important link between the conservation and utilization of plant genetic resources in various breeding programmes. In the present study, genetic variability and relationships among 25 Lactuca sativa L. genotypes were tested using random amplified polymorphic DNA (RAPD) molecular markers. A total of 45 random decamer oligonucleotide primers were examined to generate RAPD profiles, out of these reproducible patterns were obtained with 22 primers. A total of 87 amplicon were obtained, out of which all were polymorphic and 7 were unique bands. The level of polymorphism across genotypes was 100% as revealed by RAPD. Genetic similarity matrix, based on Jaccard's coefficients ranged from 13.7 to 84.10% indicating a wide genetic base. Dendrogram was constructed by unweighted pair group method with arithmetic averages method. RAPD technology could be useful for identification of different accessions as well as assessing the genetic similarity among different genotypes of lettuce. The study reveals the limited genetic base and the needs to diversify using new sources from the germplasm.

  14. Human Norovirus and Its Surrogates Induce Plant Immune Response in Arabidopsis thaliana and Lactuca sativa.

    Science.gov (United States)

    Markland, Sarah M; Bais, Harsh; Kniel, Kalmia E

    2017-08-01

    Human norovirus is the leading cause of foodborne illness worldwide with the majority of outbreaks linked to fresh produce and leafy greens. It is essential that we thoroughly understand the type of relationship and interactions that take place between plants and human norovirus to better utilize control strategies to reduce transmission of norovirus in the field onto plants harvested for human consumption. In this study the expression of gene markers for the salicylic acid (SA) and jasmonic acid (JA) plant defense pathways was measured and compared in romaine lettuce (Lactuca sativa) and Arabidopsis thaliana Col-0 plants that were inoculated with Murine Norovirus-1, Tulane Virus, human norovirus GII.4, or Hank's Balanced Salt Solution (control). Genes involving both the SA and JA pathways were expressed in both romaine lettuce and A. thaliana for all three viruses, as well as controls. Studies, including gene expression of SA- and JA-deficient A. thaliana mutant lines, suggest that the JA pathway is more likely involved in the plant immune response to human norovirus. This research provides the first pieces of information regarding how foodborne viruses interact with plants in the preharvest environment.

  15. Determination of Profenofos Pesticidal Residue in Lettuce (Lactuca sativa L. by Gas Chromatographic Method

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    Yohannes Alen

    2015-05-01

    Full Text Available The determination of profenofos pesticidal residue in the lettuce (Lactuca sativa L. by using gas chromatography using flame photometric detector (FPD had been investigated. The lettuce was collected from Padang Luar area, Agam distric, West Sumatera. Sample for determination of profenofos residue divided into three groups: unwashed (A, washed with water (B, and washed with detergent (C. Maceration with sonication was used for the extraction using ethylacetateas a solvent. The results showed that profenofos pesticide residue in sample A, B and C were 0.204, 0.080 and 0.061 ppm, respectively. These profenofos pesticidal residue are over than the Maximum Residue Limits (MRL that established by The Japan Food Chemical Research Foundation (0.05 ppm even though World Health Organization (WHO has not established Maximum Residue Limits (MRL profenofos on lettuce. Based on the statistical analysis one-way method (Anova using SPSS 20.0 showed that there was a significant concentrations difference between lettuce A from lettuce B and lettuce C with p < 0.05.

  16. Production and characterization of cyanocobalamin-enriched lettuce (Lactuca sativa L.) grown using hydroponics.

    Science.gov (United States)

    Bito, Tomohiro; Ohishi, Noriharu; Hatanaka, Yuka; Takenaka, Shigeo; Nishihara, Eiji; Yabuta, Yukinori; Watanabe, Fumio

    2013-04-24

    When lettuces (Lactuca sativa L.) grown for 30 days in hydroponic culture were treated with various concentrations of cyanocobalamin for 24 h, its content in their leaves increased significantly from nondetectable to 164.6 ± 74.7 ng/g fresh weight. This finding indicated that consumption of only two or three of these fresh leaves is sufficient to meet the Recommended Dietary Allowance for adults of 2.4 μg/day. Analyses using a cobalamin-dependent Escherichia coli 215 bioautogram and LC/ESI-MS/MS demonstrated that the cyanocobalamin absorbed from the nutrient solutions by the leaves did not alter any other compounds such as coenzymes and inactive corrinoids. Gel filtration indicated that most (86%) of the cyanocobalamin in the leaves was recovered in the free cyanocobalamin fractions. These results indicated that cyanocobalamin-enriched lettuce leaves would be an excellent source of free cyanocobalamin, particularly for strict vegetarians or elderly people with food-bound cobalamin malabsorption.

  17. Novas raças de Bremia lactucae, agente causador do míldio da alface, identificadas no estado de São Paulo New races of Bremia lactucae, causal agent of lettuce downy mildew, identified in São Paulo state, Brazil

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    Jean de O Souza

    2011-09-01

    Full Text Available O objetivo deste trabalho foi relatar o surgimento de raças de Bremia lactucae, agente causal do míldio nas principais regiões produtoras de alface do estado de São Paulo. O estudo foi realizado no Laboratório de Melhoramento Genético de Hortaliças do Departamento de Produção Vegetal da UNESP, Campus de Jaboticabal. No período de 2006 e 2007, foram coletados 36 isolados de B. lactucae de diferentes regiões produtoras de alface no estado. Para identificação das raças foram utilizadas as cultivares diferenciadoras conforme o código "Sextet". Foram identificadas três novas raças, SPBl:02, SPBl:03 e SPBl:04 com os referidos comportamentos do fungo: (63/31/19/00, (63/63/19/00 e (63/63/03/00. Os genes Dm-14, Dm-17, Dm-18, Dm-37 e Dm-38 conferem resistência a essas novas raças identificadas.The objective of this paper was to report new races of lettuce downy mildew causal agent Bremia lactucae in São Paulo State. The study was carried out in the laboratory of Crop Genetics in the Department of Crop Science at the college of Agricultural and Veterinary Sciences, Jaboticabal campus. A total of 36 isolates of B. lactucae was collected in different regions. The identification of races was based on compatibility reaction on the differential cultivars of the "Sextet". Three new races of B. lactucae, SPBl:02 (63/31/19/00, SPBl:03 (63/63/19/00 and SPBl:04 (63/63/03/00 were identified according to "Sextet" code. Genes Dm-14, Dm-17, Dm-18, Dm-37 and Dm-38 confer resistance to these new races identified.

  18. Occupational dermatitis from Lactuca sativa (lettuce) and Cichorium (endive). Simultaneous occurrence of immediate and delayed allergy as a cause of contact dermatitis.

    Science.gov (United States)

    Krook, G

    1977-02-01

    Four patients with occupational contact dermatitis to Lactuca sativa had cross-sensitivity to Cichorium endivia. One of the patients also had contact urticaria to Lactuca and Cichorium, and another reacted positively to scratch tests with these plants as a sign of immediate allergy. In two cases such immediate allergy was considered the cause of a vesicular, intense itching eruption within a few minutes of contact with fresh leaves of Lactuca on previously eczematous skin. The severe chronic dermatitis of the hands of these patients is ascribed to combined delayed and immediate allergy.

  19. PENGARUH MACAM MULSA DAN DOSIS PUPUK KANDANG AYAM TERHADAP HASIL TANAMAN SELADA (Lactuca sativa, L.) VAR. NEW GRAND RAPID

    OpenAIRE

    Herumia, Mia; Haryono, Gembong; Susilowati, Yulia Eko

    2017-01-01

    The research on the effect of mulch kinds and the effect of chiken manure doses to the lettuce yield (Lactuca sativa, L.) var New Grand Rapid. Experiment conducted in August until October 2016. Location of experiment in Dukuhan, Sumber, Dukuh, Magelang. The latitude is 663 m. The soils regosol with pH 6,3. The research method used factorial experiment (3x4) arranged in a randomized complete block design with three blocks. The first factor is mulch kind, transparant plastic mulch, black silver...

  20. Germination and growth of lettuce (Lactuca sativa) at low atmospheric pressure

    Science.gov (United States)

    Spanarkel, Robert; Drew, Malcolm C.

    2002-01-01

    The response of lettuce (Lactuca sativa L. cv. Waldmann's Green) to low atmospheric pressure was examined during the initial 5 days of germination and emergence, and also during subsequent growth to vegetative maturity at 30 days. Growth took place inside a 66-l-volume low pressure chamber maintained at 70 kPa, and plant response was compared to that of plants in a second, matching chamber that was at ambient pressure (approximately 101 kPa) as a control. In other experiments, to determine short-term effects of low pressure transients, plants were grown at ambient pressure until maturity and then subjected to alternating periods of 24 h of low and ambient atmospheric pressures. In all treatments the partial pressure of O2 was maintained at 21 kPa (approximately the partial pressure in air at normal pressure), and the partial pressure of CO2 was in the range 66.5-73.5 Pa (about twice that in normal air) in both chambers, with the addition of CO2 during the light phase. With continuous exposure to low pressure, shoot and root growth was at least as rapid as at ambient pressure, with an overall trend towards slightly greater performance at the lower pressure. Dark respiration rates were greater at low pressure. Transient periods at low pressure decreased transpiration and increased dark respiration but only during the period of exposure to low pressure. We conclude that long-term or short-term exposure to subambient pressure (70 kPa) was without detectable detriment to vegetative growth and development.

  1. RESPON DUA VARIETAS TANAMAN SELADA (Lactuca sativa L. TERHADAP MACAM NUTRISI PADA SISTEM HIDROPONIK

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    Catur Wasonowati

    2013-03-01

    Full Text Available Lettuce (Lactuca sativa L is a common vegetables crops grown in the highland and lowlands.  A sample hydroponic lettuce cultivation provides an sources an alternative for farmers who have a narrow area, so that can server as an adequate source of income.  Providing nutrients to the two varienties of lettuce are expected to yield maximum production.  This tudy aims to determine the effect of nutrients on two varieties of lettuce plants.            The study was conducted in the greenhouse Agroekoteknologi Departement Faculty of Agriculture, University Trunojoyo Madurese from January to March 2011.  The method used was a factorial experiment based on Completely Randomized Design (CRD with three replicates consisting of two treatment factors, the first factor are two different varieties of lecctuce and the second factor are two differwnt kinds of nutrients.            The results showed that the chief varieties of butter (V1 produces the number of leaves and dry biomass is higher than the varieties of cos (V2.  Nutrition in V1 generate the number of leaves, wet biomass, dry biomass, and root length was higher than without the provision of (N0. V1 responses to nutrient hidrogroup (N1 resulted in higher leaf number than nutrition greentonik (N2, but the provision of dry biomass yield N2 higher than N1. Nutrition on V2 generate the number of leaves, wet biomass and dry biomass was higher than N0. V2 response to the provision of N1 and N2 produce the number of leaves, wet biomass, dry biomass, and root length are not significantly different.Key word : lettuce, varieties, nutrition, simple hydroponics

  2. [Calcium distribution in the central cell of lettuce (Lactuca sativa L.) before and after pollination].

    Science.gov (United States)

    Qiu, Yi Lan; Liu, Ru Shi; Ye, Lv; Tian, Hui

    2008-02-01

    Potassium antimonite precipitation was used to locate calcium in the central cell of lettuce (Lactuca sativa L.) before and after pollination. At 3d before anthesis, two polar nuclei of central cell separately located at two polarity of the cell, and few calcium precipitates (ppts) appeared in the polar nuclei and cytoplasm, but some ppts in its small vacuoles. At 2d before anthesis, two polar nuclei moved toward the middle of the cell and fused to form a secondary nucleus, and the ppts evidently increased in the nucleus and cytoplasm. At 1d before anthesis, secondary nucleus again moved toward micropylar end and located near the egg to prepare for fertilization. Calcium precipitates were mainly accumulated in the secondary nucleus. After pollination and before fertilization, the distribution of calcium ppts was similar to that before pollination. At 4h after pollination, the central cell was fertilized, and calcium ppts evidently increased in the cell and numerous were accumulated in its nucleus and cytoplasm. At 6h after pollination, the primary endosperm nucleus completed its first division and formed two dissociate endosperm nuclei, and still many calcium precipitates appeared in the nucleus and cytoplasm. With endosperm development, calcium ppts decreased in the endosperm cell. At 1d after emasculated and without pollination, the secondary nucleus of the cell still bordered on the egg and some calcium ppts appeared in the secondary nucleus. The results indicated that the temporal and spatial changes of calcium in the central cell may play an important physiological role during the development of the central cell and endosperm.

  3. PENGARUH KONSENTRASI KALIUM NITRAT PADA MEDIA VERMIKOMPOS TERHADAP KANDUNGAN HARA DAN TRUBUS SELADA (LACTUCA SATIVA L.

    Directory of Open Access Journals (Sweden)

    H. J. NAMSERNA

    2012-11-01

    Full Text Available The Effect of Potassium Nitrate Concentration in Vermicompost Medium on Nutrients Content and Shoot of Lettuce (Lactuca sativa L. The content of nitrogen and potassium in vermicompost generally low, i.e. less than two percent, so that still require the addition of another source to meet crop requirement. Potassium nitrate to form the ions K+ and NO3 6 after disolved in water so as to be readily available to plants. The study aims to determine the effect of the addition of potassium nitrate in the growth medium made from vermicompost to increase growth lettuce plant and know the critical level of concentration or nutrient solution electrical conductivity with the addition of potassium nitrate to the lettuce plant. Research conducted in the form of pot experiment. Experiment using Randomized Complete Block Design (RCBD with three replications. The treatment consists of 12 levels of concentration or nutrient solution electrical conductivity with the addition of potassium nitrate. The results of experiment indicated that addition of KNO3 highly significant effect on the increasing in fresh and dry weight of shoot per plant. Fresh and dry weight of shoot per plant were significantly increased in a quadratic with increasing concentrations of KNO3. The concentration of KNO3 are optimum for growth of plant shoot weight was at 12.23 g in 100l of water or electrical conductivity equivalent to 2.01 dS.m-1. The concentrations of P and K in plant shoot tissue were significantly increased linearly with the provision of KNO3. The concentration N, Ca, Mg, S, Na, Fe, Mn, Cu, Zn, Al and B in shoot tissue of plants is not affected KNO3.

  4. [Enteroparasite determination in Lactuca sativa from farms dedicated to its production in Pasto, Colombia].

    Science.gov (United States)

    Polo, Giovanni Andrés; Benavides, Carmenza Janneth; Astaiza, Juan Manuel; Vallejo, Dario Antonio; Betancourt, Patricia

    2016-12-01

    Currently, vegetables like lettuce are widely recommended as part of the daily diet given their high nutritional value; however, while consumers feel attracted to the benefits provided by the vegetable, they may also be exposed to parasitic intestinal infections. To determine the presence or absence of enteroparasites in lettuce (Lactuca sativa) grown in the rural area in the municipality of Pasto, and to analyze associated factors based on the characterization of the lands. We conducted a descriptive double blind cross-sectional study. We took a total of 105 samples from 21 properties from June to December, 2013, and we processed them by sedimentation and flotation tests. Additionally, the owners were surveyed in order to obtain information about the possible variables influencing the occurrence of enteroparasites. We detected contamination in 100% of the lettuce samples and we found parasite eggs and larvae as follows: 95.25% with Entamoeba spp. cysts; 71.43% with Isospora spp. oocysts; 61.90% with Strongyloides stercoralis larvae (L3); 28.57% with Toxocara spp. eggs, and 4.76% with Eimeria spp. oocysts. Using the chi-square test we found association between Entamoeba spp. and ditches (p=0.008), dogs (p=0.008) and septic tanks (p=0.029); between Isospora spp. and compost (p=0.0001), dogs (p=0.0001) and slugs (p=0.002); between S. stercoralis and handling (p=0.003), and between Toxocara spp. and no use of biodigesters (p= 0.002). We found contamination with enteroparasites in lettuce samples from growing areas in the municipality of Pasto with animal and human sources as their main reservoirs, although others were present in the environment.

  5. Effect of soil cadmium on growth, photosynthesis and quality of Raphanus sativus and Lactuca sativa.

    Science.gov (United States)

    Kaur, Navjyot; Jhanji, Shalini

    2016-09-01

    Cadmium (Cd) raises serious concerns as its accumulation in the plant not only affect the growth and quality of plant but also threaten the health of consumers. In this research, two vegetables, i.e., radish (Raphanus sativus L.) and lettuce (Lactuca sativa L), were planted in pots having soil treated with Cd as Cd (NO3)2 at different doses (25, 50, 100 and 200 mg Cd kg-1 soil ) to investigate the influence of cadmium on their growth, photosynthetic attributes and quality. Cadmium retarded plant growth as dry weight of radish roots decline by 87% and leaves by 83% following 200 mg Cd kg-1 soil application and the corresponding values for lettuce were 64 and 69% respectively. Significant reductions in various photosynthetic parameters viz., leaf area per plant, total chlorophyll, Chl a and Chl b content were also recorded with Cd applications. The Cd treatments resulted in loss of membrane integrity as revealed by significant increase in electrolyte leakage in leaves of both vegetables. There was significant increase in Cd accumulation in radish and lettuce with all applications but no visual symptoms of Cd toxicity were noticed with 25 and 50 mg Cd kg-1 soil application except for yield differences, illustrating that Cd accumulate in this crop without visual evidence of its presence. However, toxicity symptoms in the form of interveinal chlorosis of the leaf lamina, followed by necrosis and leaf rolling, were clearly evident with 100 and 200 mg Cd kg-1 soil application. Apparently, Cd causes harm due to its phytotoxic effects and high accumulation in edible parts of radish and lettuce without any visible symptoms that constitutes a substantial hazard to human health.

  6. Uptake and phytotoxic effect of benzalkonium chlorides in Lepidium sativum and Lactuca sativa.

    Science.gov (United States)

    Khan, Adnan Hossain; Libby, Mark; Winnick, Daniel; Palmer, John; Sumarah, Mark; Ray, Madhumita B; Macfie, Sheila M

    2018-01-15

    Cationic surfactants such as benzalkonium chlorides (BACs) are used extensively as biocides in hospitals, food processing industries, and personal care products. BACs have the potential to reach the rooting zone of crop plants and BACs might thereby enter the food chain. The two most commonly used BACs, benzyl dimethyl dodecyl ammonium chloride (BDDA) and benzyl dimethyl tetradecyl ammonium chloride (BDTA), were tested in a hydroponic system to assess the uptake by and phytotoxicity to lettuce (Lactuca sativa L.) and garden cress (Lepidium sativum L.). Individually and in mixture, BACs at concentrations up to 100 mg L -1 did not affect germination; however, emergent seedlings were sensitive at 1 mg L -1 for lettuce and 5 mg L -1 for garden cress. After 12 d exposure to 0.25 mg L -1 BACs, plant dry weight was reduced by 68% for lettuce and 75% for garden cress, and symptoms of toxicity (necrosis, chlorosis, wilting, etc.) were visible. High performance liquid chromatography-mass spectroscopy analysis showed the presence of BACs in the roots and shoots of both plant species. Although no conclusive relationship was established between the concentrations of six macro- or six micro-nutrients, growth inhibition or BAC uptake, N and Mg concentrations in BAC-treated lettuce were 50% lower than that of control, indicating that BACs might induce nutrient deficiency. Although bioavailability of a compound in hydroponics is significantly higher than that in soil, these results confirm the potential of BACs to harm vascular plants. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Effect of acaricidal components isolated from lettuce (Lactuca sativa) on carmine spider mite (Tetranychus cinnabarinus Boisd.).

    Science.gov (United States)

    Li, M; Zhang, Y; Ding, W; Luo, J; Li, S; Zhang, Q

    2017-08-14

    This study aimed to evaluate the acaricidal activity of lettuce (Lactuca sativa) extracts against carmine spider mites (Tetranychus cinnabarinus Boisd.) and isolate the acaricidal components. Acaricidal activities of lettuce extracts isolated from different parts (the leaf, root and seed) using various solvents (petroleum ether, acetone and methanol) were evaluated with slide-dip bioassay and relatively high median lethal concentration (LC50) values were detected. Acetone extracts of lettuce leaves harvested in July and September were fractionated and isolated with silica gel and thin-layer chromatography. Consequently, acetone extracts of lettuce leaves harvested in July exhibited higher acaricidal activity than those harvested in September, with an LC50 value of 0.268 mg ml-1 at 72 h post-treatment. A total of 27 fractions were obtained from the acetone extract of lettuce leaves harvested in July, and mite mortalities with the 11th and 12th fractions were higher than those with the other 25 fractions (LC50: 0.751 and 1.258 mg ml-1 at 48 h post-treatment, respectively). Subsequently, active acaricidal components of the 11th fraction were identified by infrared, nuclear magnetic resonance and liquid chromatography/mass spectrometry. Five components were isolated from the 11th fraction, with components 11-a and 11-b showing relatively high acaricidal activities (LC50: 0.288 and 0.114 mg ml-1 at 48 h post-treatment, respectively). Component 11-a was identified as β-sitosterol. In conclusion, acetone extracts of lettuce leaves harvested in July might be used as a novel phytogenic acaricide to control mites.

  8. Evaluation of zinc oxide nanoparticles on lettuce (Lactuca sativa L.) growth and soil bacterial community.

    Science.gov (United States)

    Xu, Jiangbing; Luo, Xiaosan; Wang, Yanling; Feng, Youzhi

    2018-02-01

    The wide spread of nanoparticles (NPs) has caused tremendous concerns on agricultural ecosystem. Some metallic NPs, such as zinc oxide (ZnO), can be utilized as a nano-fertilizer when used at optimal doses. However, little is known about the responses of plant development and concomitant soil bacteria community to ZnO NPs. The present pot experiment studied the impacts of different doses of ZnO NPs and bulk ZnO (0, 1, 10, 100 mg ZnO/kg), on the growth of lettuce (Lactuca sativa L.) and the associated rhizospheric soil bacterial community. Results showed that at a dose of 10 mg/kg, ZnO NPs and bulk ZnO, enhanced the lettuce biomass and the net photosynthetic rate; whereas, the Zn content in plant tissue was higher in NPs treatment than in their bulk counterpart at 10 mg/kg dose or higher. For the underground observations, 10 mg/kg treatment doses (NPs or bulk) significantly changed the soil bacterial community structure, despite the non-significant variations in alpha diversity. Taxonomic distribution revealed that some lineages within Cyanobacteria and other phyla individually demonstrated similar or different responses to ZnO NPs and bulk ZnO. Moreover, some lineages associated with plant growth promotion were also influenced to different extents by ZnO NPs and bulk ZnO, suggesting the distinct microbial processes occurring in soil. Collectively, this study expanded our understanding of the influence of ZnO NPs on plant performance and the associated soil microorganisms.

  9. Exogenous Glycine Nitrogen Enhances Accumulation of Glycosylated Flavonoids and Antioxidant Activity in Lettuce (Lactuca sativa L.

    Directory of Open Access Journals (Sweden)

    Xiao Yang

    2017-12-01

    Full Text Available Glycine, the simplest amino acid in nature and one of the most abundant free amino acids in soil, is regarded as a model nutrient in organic nitrogen studies. To date, many studies have focused on the uptake, metabolism and distribution of organic nitrogen in plants, but few have investigated the nutritional performance of plants supplied with organic nitrogen. Lettuce (Lactuca sativa L., one of the most widely consumed leafy vegetables worldwide, is a significant source of antioxidants and bioactive compounds such as polyphenols, ascorbic acid and tocopherols. In this study, two lettuce cultivars, Shenxuan 1 and Lollo Rossa, were hydroponically cultured in media containing 4.5, 9, or 18 mM glycine or 9 mM nitrate (control for 4 weeks, and the levels of health-promoting compounds and antioxidant activity of the lettuce leaf extracts were evaluated. Glycine significantly reduced fresh weight compared to control lettuce, while 9 mM glycine significantly increased fresh weight compared to 4.5 or 18 mM glycine. Compared to controls, glycine (18 mM for Shenxuan 1; 9 mM for Lollo Rossa significantly increased the levels of most antioxidants (including total polyphenols, α-tocopherol and antioxidant activity, suggesting appropriate glycine supply promotes antioxidant accumulation and activity. Glycine induced most glycosylated quercetin derivatives and luteolin derivatives detected and decreased some phenolic acids compared to nitrate treatment. This study indicates exogenous glycine supplementation could be used strategically to promote the accumulation of health-promoting compounds and antioxidant activity of hydroponically grown lettuce, which could potentially improve human nutrition.

  10. Irradiation of lettuce (Lactuca sativa. L.): microbiological and sensory aspects;Irradiacao de alface (Lactuca sativa. L.): aspectos microbiologicos e sensoriais

    Energy Technology Data Exchange (ETDEWEB)

    Tsuhako, Vanessa Provenzano

    2005-07-01

    The increasing demand for fresh foods have stimulated the marketing of minimally processed vegetables. However, these products maintain most of their natural microbiota even after being sanitized, including pathogenic microorganisms. Refrigerated storage allows the growth of psychotropic microorganisms and among them the pathogen Listeria monocytogenes. The ingestion of food contaminated with L. monocytogenes may represent a risk to pregnant women and their fetuses and to immunocompromised people. Non-thermal alternative processes for food preservation, such as irradiation, can reduce pathogenic and spoilage microorganism populations without impairing substantial changes in sensory, physical or chemical attributes. The aims of this research were to evaluate the effect of gamma radiation on L. monocytogenes artificially inoculated on minimally processed lettuce, to evaluate its effect on lettuce leaves through acceptance sensory test and to determine the irradiated vegetable shelf life through sensory and microbiological tests. A mixture of 4 types of lettuce (Iceberg, Boston, Loose-leaf and Red loose-leaf) were artificially inoculated with L. monocytogenes (7 log UFC/g lettuce) and then exposed to 0.3; 0.6; 0.9 and 1.2 kGy, under refrigeration. The DlO values for L. monocytogenes varied fram 0.18 to 0.21 kGy. Sensory and microbiological tests indicated that the shelf life of Iceberg lettuce stored at 7 deg C was 5 and 7 days for the irradiated and non-irradiated samples, respectively, and for the irradiated and non-irradiated Loose-leaf lettuce samples were 10 days. For the non-irradiated Boston sample, the shelf life was 3 days and for the Irradiated 7 days. Red loose-leaf showed 5 and 4 days of shelf lives for the irradiated and non-irradiated, respectively. Irradiated samples presented better microbiological quality than non-irradiated ones. The irradiation is feasible process to improve quality and safety of lettuce leaves. (author)

  11. Produção de mudas de alface em bandejas e substratos comerciais

    OpenAIRE

    Trani,Paulo E.; Novo,Maria do Carmo S.S.; Cavallaro Júnior,Mário L.; Telles,Luciana M.G.

    2004-01-01

    Avaliou-se o desenvolvimento de mudas de alface (Lactuca sativa L. cv Vera) produzidas em diferentes bandejas de poliestireno e em quatro substratos comerciais em um experimento em Campinas (SP), sob cultivo protegido, de 15/01 a 13/02/03. Os tratamentos consistiram na combinação fatorial de tipos de substratos (Plantmax HA, Hortimix folhosas, Golden Mix 47 e Vida Verde Tropstrato hortaliças) e tamanhos de células em bandejas de poliestireno (200 e 288 células). O experimento foi disposto int...

  12. Molecular aspects of the antagonistic interaction of smoke-derived butenolides on the germination process of Grand Rapids lettuce (Lactuca sativa) achenes

    Czech Academy of Sciences Publication Activity Database

    Soós, V.; Sebestyén, E.; Pošta, Martin; Kohout, Ladislav; Light, M. E.; van Staden, J.; Balázs, E.

    2012-01-01

    Roč. 196, č. 4 (2012), s. 1060-1073 ISSN 0028-646X Institutional research plan: CEZ:AV0Z40550506 Keywords : abscisic acid * fire * germination * karrikinolide * Lactuca sativa * smoke Subject RIV: CE - Biochemistry Impact factor: 6.736, year: 2012

  13. LSGermOPA, a custom OPA of 384 EST-derived SNPs for high-throughput lettuce (Lactuca sativa L.) germplasm fingerprinting

    Science.gov (United States)

    We assessed the genetic diversity and population structure among 148 cultivated lettuce (Lactuca sativa L.) accessions using the high-throughput GoldenGate assay and 384 EST (Expressed Sequence Tag)-derived SNP (single nucleotide polymorphism) markers. A custom OPA (Oligo Pool All), LSGermOPA was fo...

  14. Complete genome sequence of the biofilm-formingCurtobacteriumsp. strain BH-2-1-1, isolated from lettuce (Lactuca sativa) originating from a conventional field in Norway.

    Science.gov (United States)

    Dees, Merete Wiken; Brurberg, May Bente; Lysøe, Erik

    2016-12-01

    Here, we present the 3,795,952 bp complete genome sequence of the biofilm-forming Curtobacterium sp. strain BH-2-1-1, isolated from conventionally grown lettuce ( Lactuca sativa ) from a field in Vestfold, Norway. The nucleotide sequence of this genome was deposited into NCBI GenBank under the accession CP017580.

  15. Testing the toxicity of metals, phenol, effluents, and receiving waters by root elongation in Lactuca sativa L.

    Science.gov (United States)

    Lyu, Jie; Park, Jihae; Kumar Pandey, Lalit; Choi, Soyeon; Lee, Hojun; De Saeger, Jonas; Depuydt, Stephen; Han, Taejun

    2018-03-01

    Phytotoxicity tests using higher plants are among the most simple, sensitive, and cost-effective of the methods available for ecotoxicity testing. In the present study, a hydroponic-based phytotoxicity test using seeds of Lactuca sativa was used to evaluate the water quality of receiving waters and effluents near two industrial sites (Soyo and Daejon) in Korea with respect to the toxicity of 10 metals (As, Cd, Cr, Cu, Fe, Pb, Mn, Hg, Ni, Zn) and phenol, and of the receiving waters and effluents themselves. First, the L. sativa hydroponic bioassay was used to determine whether the receiving water or effluents were toxic; then, the responsible toxicant was identified. The results obtained with the L. sativa bioassay ranked the EC 50 toxicities of the investigated metal ions and phenol as: Cd > Ni > Cu > Zn > Hg > phenol > As > Mn > Cr > Pb > Fe. We found that Zn was the toxicant principally responsible for toxicity in Daejeon effluents. The Daejeon field effluent had a higher Zn concentration than permitted by the effluent discharge criteria of the Ministry of Environment of Korea. Our conclusion on the importance of Zn toxicity was supported by the results of the L. sativa hydroponic assay, which showed that the concentration of Zn required to inhibit root elongation in L. sativa by 50% (EC 50 ) was higher in the Daejeon field effluent than that of pure Zn. More importantly, we proved that the L. sativa hydroponic test method can be applied not only as an alternative tool for determining whether a given waste is acceptable for discharge into public water bodies, but also as an alternative method for measuring the safety of aquatic environments using EC 20 values, with respect to the water pollutants investigated (i.e., Cd, Cr, Cu, Pb, Mn, Hg, Ni, Zn, and phenol). Copyright © 2017. Published by Elsevier Inc.

  16. Productividad de lechuga Lactuca sativa en condiciones de macrotúnel en suelo Vitric haplustands

    Directory of Open Access Journals (Sweden)

    Pedro Velásquez

    2014-12-01

    Full Text Available La agricultura urbana hace parte importante en la producción de alimentos para una población cada día más creciente. En este contexto, el objetivo de esta investigación fue evaluar la productividad del cultivo de lechuga Lactuca sativa var. Batavia bajo condiciones de macrotúnel con tres niveles de fertilización. El ensayo se realizó en la localidad de San Felipe, Pasto, Nariño, en un suelo Vitric haplustands; se evaluaron dos tipos de ambientes (condiciones de macrotúnel y a campo abierto, con tres niveles de fertilización: alto 115; 69; 210 kg/ha (N, P2 O5, k2O, medio 69; 23; 150 kg/ha (N, P2 O5, k2O y bajo 46; 11,5; 90 kg/ha (N, P2 O5, k2O. El macrotúnel fue construido con arcos de bambú y una cubierta plástica para invernaderos. El ensayo se estableció en un diseño de bloques completos al azar con arreglo de franjas divididas. Las variables agronómicas evaluadas fueron: peso de cabeza (PC, porcentaje de materia seca (aérea y de raíz, diámetro de cabeza (DC, días a cosecha (DCO y rendimiento (R. Además, se realizó un análisis económico de presupuesto parcial. Los resultados mostraron que el cultivo de lechuga en ambiente de macrotúnel obtuvo en: PC=2,24kg/planta; DC=20,33 cm y DCO=74 días; valores que presentaron diferencias estadísticas significativas con respecto al ambiente campo abierto. A diferencia de lo anterior el porcentaje de materia seca aérea, no presentó diferencias significativas en ninguno de los tratamientos; situación similar aconteció con las dosis de fertilización alto, medio y bajo de (N, P, K y las interacciones de estas, con los dos ambientes evaluados. El análisis económico mostró que las mayores utilidades se obtuvieron en el ambiente de macrotúnel con 11278 pesos/m2y una rentabilidad de 507%.

  17. Protective effects of Lactuca sativa ethanolic extract on carbon tetrachloride induced oxidative damage in rats

    Directory of Open Access Journals (Sweden)

    Hefnawy Taha M. Hefnawy

    2013-08-01

    Full Text Available Objective: To study the protective effects of the ethanolic extract of lettuce (Lactuca sativa L. var. longifolia leaves against the toxicity caused by carbon tetrachloride (CCl4 in reproductive system of rats. Methods: Lettuce leaves were dried and extracted with ethanol (plant: solvent, 1:10, w/v. The extract was filtered and evaporated to yield dried lettuce extract. Animals were divided into seven groups and treated with CCl4 and different concentrations of lettuce extract. At the end of the experimental period, the animals were sacrificed and blood was collected and centrifuged for serum separation. Body weights, testis size, histopathology of testis and liver, catalase (CAT activity, superoxide dismutase (SOD activity, peroxidase (POD activity, reduced glutathione (GSH, glutathione peroxidase activity (GSH-Px, thiobarbituric acid reactive substances (TBARS, nitrite level, and serum hormones were determined. Results: Oxidative stress induced by CCl4 (2 mL/kg body weight in rat decreases the increase in body weight and relative testis weight. It also markedly increases the level of TBARS and nitrites along with corresponding decrease in reduced glutathione and various antioxidant enzymes in testis (i.e., CAT, POD, SOD and GSH-Px. Serum level of testosterone, luteinizing hormone and follicle stimulating hormone was decreased while estradiol and prolactin were increased during CCl 4 treatment. Histopathology of CCl4-treated rats indicated the partial degeneration of germ and leydig cells along with deformities in spermatogenesis. Supplementation of lettuce extract (100, 150, 200 mg/kg body weight orally once a week for 10 weeks results in decrease of TBARS and nitrite, while increase in antioxidant enzymes; CAT, POD, SOD, GSH-Px and GSH contents. Serum level of testosterone, luteinizing hormone, follicle stimulating hormone, estradiol, prolactin, histology, body weight and relative testis weight was also concomitantly restored to near normal

  18. Protective effects of Lactuca sativa ethanolic extract on carbon tetrachloride induced oxidative damage in rats

    Science.gov (United States)

    Hefnawy, Hefnawy Taha M.; Ramadan, Mohamed Fawzy

    2013-01-01

    Objective To study the protective effects of the ethanolic extract of lettuce (Lactuca sativa L. var. longifolia) leaves against the toxicity caused by carbon tetrachloride (CCl4) in reproductive system of rats. Methods Lettuce leaves were dried and extracted with ethanol (plant: solvent, 1:10, w/v). The extract was filtered and evaporated to yield dried lettuce extract. Animals were divided into seven groups and treated with CCl4 and different concentrations of lettuce extract. At the end of the experimental period, the animals were sacrificed and blood was collected and centrifuged for serum separation. Body weights, testis size, histopathology of testis and liver, catalase (CAT) activity, superoxide dismutase (SOD) activity, peroxidase (POD) activity, reduced glutathione (GSH), glutathione peroxidase activity (GSH-Px), thiobarbituric acid reactive substances (TBARS), nitrite level, and serum hormones were determined. Results Oxidative stress induced by CCl4 (2 mL/kg body weight) in rat decreases the increase in body weight and relative testis weight. It also markedly increases the level of TBARS and nitrites along with corresponding decrease in reduced glutathione and various antioxidant enzymes in testis (i.e., CAT, POD, SOD and GSH-Px). Serum level of testosterone, luteinizing hormone and follicle stimulating hormone was decreased while estradiol and prolactin were increased during CCl4 treatment. Histopathology of CCl4-treated rats indicated the partial degeneration of germ and leydig cells along with deformities in spermatogenesis. Supplementation of lettuce extract (100, 150, 200 mg/kg body weight orally) once a week for 10 weeks results in decrease of TBARS and nitrite, while increase in antioxidant enzymes; CAT, POD, SOD, GSH-Px and GSH contents. Serum level of testosterone, luteinizing hormone, follicle stimulating hormone, estradiol, prolactin, histology, body weight and relative testis weight was also concomitantly restored to near normal level by

  19. Comparative allelopathic effects of Cryptocarya moschata and Ocotea odorifera aqueous extracts on Lactuca sativa - doi: 10.4025/actasciagron.v35i2.15758

    Directory of Open Access Journals (Sweden)

    Franciele Carla Prichoa

    2012-12-01

    Full Text Available The aim of this work was to compare the allelopathic effects of aqueous leaf extracts from Cryptocarya moschata and Ocotea odorifera on the seed germination and initial growth of Lactuca sativa (lettuce. The extracts were prepared by cold maceration, which was accomplished by adding distilled water to the dried plant material 1:10 (w v-1 and grinding. The treatment concentrations (0, 0.25, 0.5, 0.75 and 1% were obtained by dissolving the dried crude extract in distilled water. The allelopathic potential of the dried Ocotea odorifera and Cryptocarya moschata leaves on Lactuca sativa was observed through reduction of the percentage of seeds that germinated, the index of germination and the length of the roots as well as structural abnormalities in L. sativa seedlings. For both extracts, the extract concentration and allelopathic effect were highly correlated. However, the C. moschata extract had no effect on caulicle length at the different tested concentrations.

  20. Allelopathic evaluation of ethanol extracts of Copaifera sabulicola on the initial development of Lactuca sativa, Lycopersicum esculentum, and Zea mays

    Directory of Open Access Journals (Sweden)

    Manoel Viana Linhares Neto

    2014-05-01

    Full Text Available http://dx.doi.org/10.5007/2175-7925.2014v27n3p23 This paper aimed to evaluate the allelopathic potential of ethanol extracts from stem and leaves of Copaifera sabulicola on seed germination and seedling growth of Lactuca sativa and Lycopersicum esculentum, as well as to evaluate the allelopathic effect of these extracts on seedling germination and growth of Zea mays, through bioassays under laboratory conditions. The extracts were tested at the concentrations 0, 250, 500, and 1,000 mg.L-1. We evaluated the germination percentage, germination average speed, germination speed index, and seedling average length. All parameters underwent variance analysis, and the mean values were compared by means of Scott-Knott test (p ≤ 0.05. We found out that, in L. sativa, the extract from stem promoted significant stimuli on germination percentage and root growth, while the extract from leaves only stimulated root growth. In L. esculentum, the extract from stem promoted significant stimulus on hypocotyl and root growth, in turn, the extract from leaves stimulated only root growth. In Z. mays, both extracts significantly inhibited germination. Therefore, we found out the allelopathic potential of ethanol extracts of C. sabulicola on L. sativa and L. esculentum, as well as inhibitory allelopathic effect on Z. mays.

  1. Heavy metals deposited in the culture of lettuce (Lactuca sativa L.) by the influence of vehicular traffic in Pernambuco, Brazil.

    Science.gov (United States)

    França, Fernanda C S S; Albuuerque, Adriana M A; Almeida, Amanda C; Silveira, Patrícia B; Filho, Crescêncio A; Hazin, Clovis A; Honorato, Eliane V

    2017-01-15

    Currently one of the main sources of atmospheric pollution identified in urban centers is derived from both industrial and motor vehicle emissions. These pollutants can be adsorbed to particulate matter which is present in the air or deposited in the soil and plants, eventually reaching the human food chain. In this context, the present study aimed to determine the concentration of metals such as Cu, Pb, Cd, Ni and Zn in two subspecies of Lactuca sativa L. and in the soil from were lettuce samples were collected. The results for the soil samples analyzed show a possible contamination by Pb with concentration values as high as 140mg.kg(-1), which are above the Brazilian standards defined by Resolution CONAMA 420/2009 (Brazilian Environmental Council). However, the values found in the lettuce itself reveal that it is still suitable for consumption. Copyright © 2016. Published by Elsevier Ltd.

  2. Agronomical response of lettuce (Lactuca sativa L., variety “Black Seed Simpson”, to Enerplant biostimulant aplication

    Directory of Open Access Journals (Sweden)

    Michel Baldoquin Hernandez

    2015-03-01

    Full Text Available The research was done at the school vegetable garden of Los Indios in the municipality of Rio Cauto, Granma, from March through April, 2014. The objective was to evaluate the agronomical response of the cultivation of the lettuce (Lactuca sativa. L variety “Black Seeded Simpson to the foliar application of three doses of Enerplant. The biostimulant was applied in the morning 7 days after transplantation. The doses used were 0.5 mL.ha-1, 1 mL.ha-1 and 1.5 mL.ha-1. The yield components were evaluated. The obtained data were statistically processed using the software package STASTISTICA 6.0 for Windows. Results showed that the three doses had a positive effect on the cultivation yield. Best results were obtained with the application of the 1.5 mL.ha-1 dose. The majority of the evaluated indicators significantly increased.

  3. [Agrobacterium-mediated transformation of lettuce (Lactuca sativa L.) with vectors bearing genes of bacterial antigenes from Mycobacterium tuberculosis].

    Science.gov (United States)

    Marveeva, N A; Vasilenko, M Iu; Shakhovskiĭ, A M; Kuchuk, N V

    2009-01-01

    Transgenic plants of lettuce Lactuca sativa L. cv. Eralash, Sniezinka, Rubinovoje kruzevo with genes coding synthesis of tuberculosis antigenes have been obtained by Agrobacterium-mediated transformation. Cotyledons of in vitro seedlings were used as the initial material for transformation with plasmids pCB063 (genes ESAT6, nptII) and pCB064 (genes ESAT6:AG85B(-TMD), nptII). PCR-analysis has shown the presence both selective and target genes in all plants analyzed. At the same time, the RT-PCR has shown that both the presence and the absence of a transcription of gene ESAT6 at a stable transcription of a gene nptII is possible.

  4. Experimental determinations of soil copper toxicity to lettuce (Lactuca sativa) growth in highly different copper spiked and aged soils

    DEFF Research Database (Denmark)

    Christiansen, Karen Søgaard; Borggaard, Ole K.; Holm, Peter Engelund

    2015-01-01

    Accurate knowledge about factors and conditions determining copper (Cu) toxicity in soil is needed for predicting plant growth in various Cu-contaminated soils. Therefore, effects of Cu on growth (biomass production) of lettuce (Lactuca sativa) were tested on seven selected, very different soils...... of dissolved organic carbon [DOC] which together could explain 87 % of the pEC50(Cu2+) variation according to the simple equation: pEC50(Cu2+) = 0.98 × pH + 345 × [DOC] − 0.27. Other soil characteristics, including the base cation concentrations (Na+, K+, Ca2+, Mg2+), the cation exchange capacity at soil p......H (ECEC), and at pH 7 (CEC7), soil organic carbon, clay content, and electric conductivity as well as the distribution coefficient (Kd) calculated as the ratio between total soil Cu and water-extractable Cu did not correlate significantly with pEC50(Cu2+). Consequently, Cu toxicity, expressed...

  5. Fitotoxicidade e citogenotoxicidade da água e sedimento de córrego urbano em bioensaio com Lactuca sativa

    Directory of Open Access Journals (Sweden)

    Luiz C. de A. Rodrigues

    2013-10-01

    Full Text Available Objetivou-se, com este trabalho, avaliar a influência espacial e temporal da fitotoxicidade e da citogenotoxicidade da água e do sedimento de córrego urbano quanto às características germinativas e de crescimento inicial de Lactuca sativa. Amostras de água e de sedimento foram coletadas em 5 pontos do Córrego do Pântano (Alfenas, Minas Gerais, no período de outubro de 2010 a julho de 2011 e as concentrações dos metais Cd, Pb e Zn foram quantificadas. Os ensaios de fitotoxicidade e de citogenotoxicidade foram realizados com as amostras de água e extratos aquosos dos sedimentos. Os parâmetros avaliados foram taxa de germinação, comprimento de raízes, biomassa fresca e seca, índice mitótico e a frequência de anormalidades cromossômicas. Constataram-se maiores concentrações de Cd e Pb nas amostras de água coletadas nos meses com a ocorrência de precipitações pluviométricas. Água e sedimento apresentaram efeito fitotóxico sobre germinação, biomassa fresca e seca de Lactuca sativa. O comprimento de raízes foi estimulado e apenas as amostras de água reduziram o índice mitótico. Evidenciou-se, também, variação temporal significativa relacionada com o regime pluviométrico apenas para o teste de fitotoxicidade.

  6. Relação entre coeficientes de cultura e graus-dia de desenvolvimento da alface

    OpenAIRE

    Silva, Elio L. da; Martinez, Leôncio F.; Yitayew, Muluneh

    1999-01-01

    Este estudo foi conduzido na Fazenda Campbell da Universidade do Arizona , no período de junho de 1994 a fevereiro de 1995, com objetivo de determinar a equação do coeficiente de cultura (Kc) como função de graus-dia de desenvolvimento (GDD) usando a série de senos Fourier, para alface (Lactuca sativa, L.), do tipo folhosa. Foram usadas dez parcelas casualizadas, irrigadas de maneira a manter o potencial matricial da água no solo acima ou igual a -20kPa, que constituiram as repetições na dete...

  7. Analysis of bacteria, parasites, and heavy metals in lettuce (Lactuca sativa) and rocket salad (Eruca sativa L.) irrigated with treated effluent from a biological wastewater treatment plant.

    Science.gov (United States)

    Nikaido, Meire; Tonani, Karina A A; Julião, Fabiana C; Trevilato, Tânia M B; Takayanagui, Angela M M; Sanches, Sérgio M; Domingo, José L; Segura-Muñoz, Susana I

    2010-06-01

    This study aimed to evaluate the viability of using treated residuary water from the Biological Wastewater Treatment Plant of Ribeirão Preto to grow vegetables, through the characterization and quantification of parasites, coliforms, and heavy metals. Three equal cultivation areas were prepared. The first was irrigated with treated/chlorinated (0.2 mg L(-1)) wastewater, the second one with treated wastewater without chlorination, and the third site with potable water, which was the control group. The presence of Hymenolepis nana, Enterobius vermicularis, nematode larvae, and Entamoeba coli was verified in lettuce (Lactuca sativa) samples. Although nematode larvae were observed in rocket salad (Eruca sativa L.), no significant differences were found between the number of parasites and type of irrigation water used. No significant differences were found between the number of fecal coliforms in vegetables and the different types of irrigation. However, the vegetables irrigated with treated effluent without chlorination showed higher levels of fecal coliforms. The risk of pathogens is reduced with bleach addition to the treated effluent at 0.2 mg/L. Concentration of heavy metals in vegetables does not mean significant risks to human health, according with the parameters recommended by the World Health Organization.

  8. ATIVIDADE ALELOPÁTICA DE Araucaria angustifolia (Bertol. Kuntze NA GERMINAÇÃO E CRESCIMENTO INICIAL DE Lactuca sativa L.

    Directory of Open Access Journals (Sweden)

    Bruna Denardin da Silveira

    2014-01-01

    Full Text Available The present study aimed to evaluate the possible allelopathic activities effects from Araucaria angustifolia on Lactuca sativa germination and initial growth. For this trial, lettuce seeds were used and aqueous extract extracted from the leaves of araucaria, with concentrations of 10%, 7.5%, 5.0% and 2.5%. The effect of the - se four concentrations was compared with distilled water (concentration 0%. Based on the collected data, percentage of germination (G%, germination speed index (GSI, average germination time (t, seedlings length and dried mass were determined. Results showed that aqueous extract from araucaria leaves has an inhibitory property on germination, germination speed index and initial growth in Lactuca sativa.

  9. Plant growth-promoting bacterium Acinetobacter calcoaceticus P23 increases the chlorophyll content of the monocot Lemna minor (duckweed) and the dicot Lactuca sativa (lettuce).

    Science.gov (United States)

    Suzuki, Wakako; Sugawara, Masayuki; Miwa, Kyoko; Morikawa, Masaaki

    2014-07-01

    Acinetobacter calcoaceticus P23 is a plant growth-promoting bacterium that was isolated from the surface of duckweed (Lemna aoukikusa). The bacterium was observed to colonize on the plant surfaces and increase the chlorophyll content of not only the monocotyledon Lemna minor but also the dicotyledon Lactuca sativa in a hydroponic culture. This effect on the Lactuca sativa was significant in nutrient-poor (×1/100 dilution of H2 medium) and not nutrient-rich (×1 or ×1/10 dilutions of H2 medium) conditions. Strain P23 has the potential to play a part in the future development of fertilizers and energy-saving hydroponic agricultural technologies. Copyright © 2013 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  10. Complete genome sequence of the biofilm-formingMicrobacteriumsp. strain BH-3-3-3, isolated from conventional field-grown lettuce (Lactuca sativa) in Norway.

    Science.gov (United States)

    Dees, Merete Wiken; Brurberg, May Bente; Lysøe, Erik

    2017-03-01

    The genus Microbacterium contains bacteria that are ubiquitously distributed in various environments and includes plant-associated bacteria that are able to colonize tissue of agricultural crop plants. Here, we report the 3,508,491 bp complete genome sequence of Microbacterium sp. strain BH-3-3-3, isolated from conventionally grown lettuce ( Lactuca sativa ) from a field in Vestfold, Norway. The nucleotide sequence of this genome was deposited into NCBI GenBank under the accession CP017674.

  11. UTILIZAÇÃO DE COMPOSTOS ORGÂNICOS SEMICURADOS NA PRODUÇÃO DA ALFACE (LACTUCA SATIVA

    Directory of Open Access Journals (Sweden)

    Fabio Fernando Araújo

    2008-01-01

    Full Text Available In order to evaluate the effects of two doses of organics composts of two different origins in the lettuce yield was conduced this work. The composts, originated from mixture of straw brachiaria seed, cattle manure and chicken manure. The composting was conduced by 35 days with monitoring of temperature. Lettuce yield was evaluated in experiment carried during 30 days. The chicken manure compost increased lettuce yield in the two doses evaluated. The cattle manure compost didn¿t increased the growth of lettuce in the larger dose. The chicken manure compost, with 35 days, was recommeded for utilization in the fertilization of lettuce with increments in the yeld.

  12. Relação entre coeficientes de cultura e graus-dia de desenvolvimento da alface Relationship between lettuce crop coeficient and growing degree days

    OpenAIRE

    Elio L. da Silva; Leôncio F. Martinez; Muluneh Yitayew

    1999-01-01

    Este estudo foi conduzido na Fazenda Campbell da Universidade do Arizona , no período de junho de 1994 a fevereiro de 1995, com objetivo de determinar a equação do coeficiente de cultura (Kc) como função de graus-dia de desenvolvimento (GDD) usando a série de senos Fourier, para alface (Lactuca sativa, L.), do tipo folhosa. Foram usadas dez parcelas casualizadas, irrigadas de maneira a manter o potencial matricial da água no solo acima ou igual a -20kPa, que constituiram as repetições na dete...

  13. Beneficial Phytochemicals with Anti-Tumor Potential Revealed through Metabolic Profiling of New Red Pigmented Lettuces (Lactuca sativa L.

    Directory of Open Access Journals (Sweden)

    Xiao-Xiao Qin

    2018-04-01

    Full Text Available The present study aimed to compare polyphenols among red lettuce cultivars and identify suitable cultivars for the development and utilization of healthy vegetables. Polyphenols, mineral elements, and antioxidant activity were analyzed in the leaves of six red pigmented lettuce (Lactuca sativa L. cultivars; thereafter, we assessed the anti-tumor effects of cultivar B-2, which displayed the highest antioxidant activity. Quadrupole–Orbitrap mass spectrometry analysis revealed four classes of polyphenols in these cultivars. The composition and contents of these metabolites varied significantly among cultivars and primarily depended on leaf color. The B-2 cultivar had the highest antioxidant potential than others because it contained the highest levels of polyphenols, especially anthocyanin, flavone, and phenolic acid; furthermore, this cultivar displayed anti-tumor effects against the human lung adenocarcinoma cell line A549, human hepatoma cell line Bel7402, human cancer colorectal adenoma cell line HCT-8, and HT-29 human colon cancer cell line. Hence, the new red-leaf lettuce cultivar B-2 has a distinct metabolite profile, with high potential for development and utilization of natural phytochemical and mineral resources in lettuces and can be used as a nutrient-dense food product.

  14. Validation of a Method for Cylindrospermopsin Determination in Vegetables: Application to Real Samples Such as Lettuce (Lactuca sativa L.

    Directory of Open Access Journals (Sweden)

    Ana I. Prieto

    2018-02-01

    Full Text Available Reports on the occurrence of the cyanobacterial toxin cylindrospermopsin (CYN have increased worldwide because of CYN toxic effects in humans and animals. If contaminated waters are used for plant irrigation, these could represent a possible CYN exposure route for humans. For the first time, a method employing solid phase extraction and quantification by ultra-performance liquid chromatography–tandem mass spectrometry (UPLC-MS/MS of CYN was optimized in vegetables matrices such as lettuce (Lactuca sativa. The validated method showed a linear range, from 5 to 500 ng CYN g−1 of fresh weight (f.w., and detection and quantitation limits (LOD and LOQ of 0.22 and 0.42 ng CYN g−1 f.w., respectively. The mean recoveries ranged between 85 and 104%, and the intermediate precision from 12.7 to 14.7%. The method showed to be robust for the three different variables tested. Moreover, it was successfully applied to quantify CYN in edible lettuce leaves exposed to CYN-contaminated water (10 µg L−1, showing that the tolerable daily intake (TDI in the case of CYN could be exceeded in elderly high consumers. The validated method showed good results in terms of sensitivity, precision, accuracy, and robustness for CYN determination in leaf vegetables such as lettuce. More studies are needed in order to prevent the risks associated with the consumption of CYN-contaminated vegetables.

  15. Preliminary studies on growth and fresh weight of lettuce (Lactuca sativa) as affected by clay pot irrigation and spacing.

    Science.gov (United States)

    Abubakari, Abdul-Halim; Nyarko, George; Maalinyuur, Sheila

    2011-07-15

    An experiment (Completely Randomized Design) was set up to determine the effects of Clay Pot Sub-surface Irrigation (CPSI) and spacing on the growth and fresh weight of lettuce (Lactuca sativa). The treatments were: CPSI with spacing; 15 x 15 cm, 20 x 20 cm and 30 x 30 cm. Control treatments were Watering Can Irrigation (WCI) with the same spacing as above. Treatments were replicated three times given a total of 18 experimental units. Eighteen large enamel basins of 50/20 cm (diameter/height) were filled with good topsoil and a clay pot buried neck deep in each of the basins. Seedlings were planted in all the eighteen basins. Five Hundred mL of wastewater was applied daily to plants in each container having either clay pot or watering can treatment. Plant height increased from 2.50 to 4.25 cm within 6 Weeks after Transplanting (WAT) under CPSI and only increased from 2.14 to 2.99 cm under WCI. The CPSI also supported better leave growth and fresh weight. The fresh weight of lettuce increased almost two fold under 15 x 15 cm spacing compared to 20 x 20 and 30 x 30 cm.

  16. Effects of microcystin-LR, linear alkylbenzene sulfonate and their mixture on lettuce (Lactuca sativa L.) seeds and seedlings.

    Science.gov (United States)

    Wang, Zhi; Xiao, Bangding; Song, Lirong; Wu, Xingqiang; Zhang, Junqian; Wang, Chunbo

    2011-06-01

    Microcystin-LR (MCLR) and linear alkylbenzene sulfonate (LAS) are present widely in aquatic and terrestrial ecosystems, but their combined ecotoxicological risk is unknown. This study investigated the toxic effects of MCLR, LAS and their mixture on lettuce (Lactuca sativa L.) and evaluated MCLR accumulation level in lettuce with or without LAS. The changes in seed germination and shoot/root growth, responses of the antioxidative defense system, and the accumulation of MCLR in lettuce were tested to evaluate the single and combined toxic effect of MCLR and LAS in well-controlled conditions. The results showed that seedling growth (except for root elongation and leaf weight) was more sensitive to toxicant exposure than seed germination. For seedling leaves, lipid peroxidation was not observed when the antioxidative defense system (including superoxide dismutase, catalase and glutathione) was activated to relieve the adverse effects of oxidative stress via different pathways. Our results also confirmed that the interaction between MCLR and LAS was synergistic. Both toxicants in combination not only significantly inhibited seedling growth, but also increased the activities of superoxide dismutase and catalase, as well as the contents of glutathione. Furthermore, LAS dramatically enhanced the accumulation of MCLR in the plant, thus leading to a reduction in quality and yield and posing greater potential risk to humans via consumption of these edible plants.

  17. Role of manganese in low-pH-induced root hair formation in Lactuca sativa cv. Grand Rapids seedlings.

    Science.gov (United States)

    Konno, Masae; Ooishi, Machiko; Inoue, Yasunori

    2003-08-01

    Root hair formation is induced by low pH in lettuce ( Lactuca sativa L. cv. Grand Rapids) seedlings cultured in mineral medium. The role of mineral concentrations in this phenomenon was investigated, especially for manganese. When lettuce seedlings were cultured in media that were deficient in calcium (Ca), manganese (Mn), boron (B) or molybdenum (Mo), morphological changes were induced in roots. Deficiency of other nutrients had little effect on root hair formation. Ca or B deficiency inhibited the growth of the main root and the formation of root hairs, regardless of pH. Mn or Mo deficiency increased root hair formation at pH 6 and suppressed main root growth slightly. In contrast, increasing the Mn concentration suppressed low-pH-induced root hair formation. The Mn content of roots grown at pH 4 was only about 15% of that at pH 6. In contrast, the Mo content of roots grown at low pH was about six times that of roots grown at neutral pH. These results suggest that root hair formation induced by low pH is at least partly mediated by decreased Mn uptake in root cells.

  18. Inflorescence Development and the Role of LsFT in Regulating Bolting in Lettuce (Lactuca sativa L.

    Directory of Open Access Journals (Sweden)

    Zijing Chen

    2018-01-01

    Full Text Available Lettuce (Lactuca sativa L. is one of the most important leafy vegetable that is consumed during its vegetative growth. The transition from vegetative to reproductive growth is induced by high temperature, which has significant economic effect on lettuce production. However, the progression of floral transition and the molecular regulation of bolting are largely unknown. Here we morphologically characterized the inflorescence development and functionally analyzed the FLOWERING LOCUS T (LsFT gene during bolting regulation in lettuce. We described the eight developmental stages during floral transition process. The expression of LsFT was negatively correlated with bolting in different lettuce varieties, and was promoted by heat treatment. Overexpression of LsFT could recover the late-flowering phenotype of ft-2 mutant. Knockdown of LsFT by RNA interference dramatically delayed bolting in lettuce, and failed to respond to high temperature. Therefore, this study dissects the process of inflorescence development and characterizes the role of LsFT in bolting regulation in lettuce.

  19. Physiological Mechanisms Only Tell Half Story: Multiple Biological Processes are involved in Regulating Freezing Tolerance of Imbibed Lactuca sativa Seeds.

    Science.gov (United States)

    Jaganathan, Ganesh K; Han, Yingying; Li, Weijie; Song, Danping; Song, Xiaoyan; Shen, Mengqi; Zhou, Qiang; Zhang, Chenxue; Liu, Baolin

    2017-03-13

    The physiological mechanisms by which imbibed seeds survive freezing temperatures in their natural environment have been categorized as freezing avoidance by supercooling and freezing tolerance by extracellular freeze-desiccation, but the biochemical and molecular mechanisms conferring seed freezing tolerance is unexplored. In this study, using imbibed Lactuca sativa seeds we show that fast cooled seeds (60 °C h -1 ) suffered significantly higher membrane damage at temperature between -20 °C and -10 °C than slow cooled (3 °Ch -1 ) seeds (P  0.05). However, both SOD activity and accumulation of free proline were induced significantly after slow cooling to -20 °C compared with fast cooling. RNA-seq demonstrated that multiple pathways were differentially regulated between slow and fast cooling. Real-time verification of some differentially expressed genes (DEGs) revealed that fast cooling caused mRNA level changes of plant hormone and ubiquitionation pathways at higher sub-zero temperature, whilst slow cooling caused mRNA level change of those pathways at lower sub-zero ttemperatures. Thus, we conclude that imbibed seed tolerate low temperature not only by physiological mechanisms but also by biochemical and molecular changes.

  20. Inflorescence Development and the Role of LsFT in Regulating Bolting in Lettuce (Lactuca sativa L.)

    Science.gov (United States)

    Chen, Zijing; Han, Yingyan; Ning, Kang; Ding, Yunyu; Zhao, Wensheng; Yan, Shuangshuang; Luo, Chen; Jiang, Xiaotang; Ge, Danfeng; Liu, Renyi; Wang, Qian; Zhang, Xiaolan

    2018-01-01

    Lettuce (Lactuca sativa L.) is one of the most important leafy vegetable that is consumed during its vegetative growth. The transition from vegetative to reproductive growth is induced by high temperature, which has significant economic effect on lettuce production. However, the progression of floral transition and the molecular regulation of bolting are largely unknown. Here we morphologically characterized the inflorescence development and functionally analyzed the FLOWERING LOCUS T (LsFT) gene during bolting regulation in lettuce. We described the eight developmental stages during floral transition process. The expression of LsFT was negatively correlated with bolting in different lettuce varieties, and was promoted by heat treatment. Overexpression of LsFT could recover the late-flowering phenotype of ft-2 mutant. Knockdown of LsFT by RNA interference dramatically delayed bolting in lettuce, and failed to respond to high temperature. Therefore, this study dissects the process of inflorescence development and characterizes the role of LsFT in bolting regulation in lettuce. PMID:29403510

  1. Evaluation of the toxic potential of coffee wastewater on seeds, roots and meristematic cells of Lactuca sativa L.

    Science.gov (United States)

    Aguiar, Luara Louzada; Andrade-Vieira, Larissa Fonseca; de Oliveira David, José Augusto

    2016-11-01

    Coffee wastewater (CWW) is an effluent produced through wet processing of coffee containing high concentration of organic matter, nutrients, salts and also agrochemicals. It is released directly into the argillaceous soil or into decantation tanks for later disposal into soils, by fertigation, subsurface infiltration or superficial draining. However, this practice is not followed by the monitoring the toxicity potential of this effluent. In this sense, the present work aimed to evaluate the phytotoxic, cytogenotoxic and mutagenic potential of CWW on seed germination, root elongation and cell cycle alterations in the plant model Lactuca sativa L. The effluent (CWW) collected was diluted in distilled water into six concentrations solutions (1.25%, 1.66%, 2.5%, 5.0%, 10%, 20%). A solution of raw CWW (100%) was also applied. Distilled water was used as negative control), and the DNA alkylating agent, metilmetano sulfonate (4×10(-4)M) as positive control. Physico-chemical parameters of the CWW was accessed and it was found that the effluent contained total phenols and inorganic matter in amounts within the limits established by the National Environment Council (CONAMA). Nevertheless, the biologicals assays performed demonstrated the phytotoxicity and cytogenotoxicty of CWW. Seed germination was totally inhibited after exposure of raw CWW. In addition, a decrease in seed germination speed as well as in root growth dose-dependently manner was noticed. Moreover, nuclear and chromosomal alterations were observed in the cell cycle, mostly arising from aneugenic action. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. Anti-inflammatory and antioxidant activity of polyphenolic extracts from Lactuca sativa (var. Maravilla de Verano) under different farming methods.

    Science.gov (United States)

    Adesso, Simona; Pepe, Giacomo; Sommella, Eduardo; Manfra, Michele; Scopa, Antonio; Sofo, Adriano; Tenore, Gian Carlo; Russo, Mariateresa; Di Gaudio, Francesca; Autore, Giuseppina; Campiglia, Pietro; Marzocco, Stefania

    2016-09-01

    Besides their nutritional value, vegetables are a source of health-promoting compounds, such as polyphenols, and their content can be influenced by the particular farming method. In this study polyphenolic extracts from Lactuca sativa (var. Maravilla de verano) plants cultivated with different farming methods were chemically characterised and tested in vitro and ex vivo inflammation models. The tested extacts (250-2.5 µg mL(-1) ) were able to reduce both the inflammatory and oxidative stress in LPS-stimulated J774A.1 murine monocyte macrophage cells, by lowering the release of nitric oxide (NO) and reactive oxygen species (ROS) and promoting nuclear translocation of nuclear factor (erythroid-derived 2)-like 2; (Nrf2) and nuclear factor-κB (NF-κB). In this regard, quantitative profiles revealed different amounts of polyphenols, in particular quercetin levels were higher in plants under mineral fertilised treatment. Those extract showed an enhanced anti-inflammatory and antioxidant activity. Our data showed the anti-inflammatory and antioxidant potential of Maravilla de Verano polyphenolic extracts. The effect of farming methods on polyphenolic levels was highlighted. The higher reduction of inflammatory mediators release in extracts from plants cultivated under mineral fertilisation treatment was correlated to the higher amount of quercetin. These results can be useful for both nutraceutical or agronomic purposes. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  3. Molecular characterization of a divergent strain of calla lily chlorotic spot virus infecting celtuce (Lactuca sativa var. augustana) in China.

    Science.gov (United States)

    Wu, Xiaodong; Wu, Xiaoyun; Li, Wenbin; Cheng, Xiaofei

    2018-02-01

    Through sequencing and assembly of small RNAs, an orthotospovirus was identified from a celtuce plant (Lactuca sativa var. augustana) showing vein clearing and chlorotic spots in the Zhejiang province of China. The S, M, and L RNAs of this orthotospovirus were determined to be 3146, 4734, and 8934 nt, respectively, and shared 30.4-72.5%, 43.4-80.8%, and 29.84-82.9% nucleotide sequence identities with that of known orthotospoviruses. The full length nucleoprotein (N) of this orthotospovirus shared highest amino acid sequence identity (90.25%) with that of calla lily chlorotic spot virus isolated from calla lily (CCSV-calla) [China: Taiwan: 2001] and tobacco (CCSV-LJ1) [China: Lijiang: 2014]. Phylogenetic analyses showed that this orthotospovirus is phylogenetically associated with CCSV isolates and clustered with CCSV, tomato zonate spot virus (TZSV), and tomato necrotic spot-associated virus (TNSaV) in a separate sub-branch. These results suggest that this orthotospovirus is a divergent isolate of CCSV and was thus named CCSV-Cel [China: Zhejiang: 2017].

  4. Validation of a Method for Cylindrospermopsin Determination in Vegetables: Application to Real Samples Such as Lettuce (Lactuca sativa L.).

    Science.gov (United States)

    Prieto, Ana I; Guzmán-Guillén, Remedios; Díez-Quijada, Leticia; Campos, Alexandre; Vasconcelos, Vitor; Jos, Ángeles; Cameán, Ana M

    2018-02-01

    Reports on the occurrence of the cyanobacterial toxin cylindrospermopsin (CYN) have increased worldwide because of CYN toxic effects in humans and animals. If contaminated waters are used for plant irrigation, these could represent a possible CYN exposure route for humans. For the first time, a method employing solid phase extraction and quantification by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) of CYN was optimized in vegetables matrices such as lettuce ( Lactuca sativa ). The validated method showed a linear range, from 5 to 500 ng CYN g -1 of fresh weight (f.w.), and detection and quantitation limits (LOD and LOQ) of 0.22 and 0.42 ng CYN g -1 f.w., respectively. The mean recoveries ranged between 85 and 104%, and the intermediate precision from 12.7 to 14.7%. The method showed to be robust for the three different variables tested. Moreover, it was successfully applied to quantify CYN in edible lettuce leaves exposed to CYN-contaminated water (10 µg L -1 ), showing that the tolerable daily intake (TDI) in the case of CYN could be exceeded in elderly high consumers. The validated method showed good results in terms of sensitivity, precision, accuracy, and robustness for CYN determination in leaf vegetables such as lettuce. More studies are needed in order to prevent the risks associated with the consumption of CYN-contaminated vegetables.

  5. Effect of salicylhydroxamic acid on endosperm strength and embryo growth of Lactuca sativa L. cv Waldmann's Green seeds

    Science.gov (United States)

    Brooks, C. A.; Mitchell, C. A.

    1988-01-01

    Salicylhydroxamic acid (SHAM) stimulated germination of photosensitive lettuce (Lactuca sativa L. cv Waldmann's Green) seeds in darkness. To determine whether SHAM acts on the embryo or the endosperm, we investigated separately effects of SHAM on growth potential of isolated embryos as well as on endosperm strength. Embryo growth potential was quantified by incubating decoated embryos in various concentrations of osmoticum and measuring subsequent radicle elongation. Growth potential of embryos isolated from seeds pretreated with 4 millimolar SHAM was equal to that of untreated controls. Rupture strength of endosperm tissue excised from seeds pretreated with SHAM was 33% less than that of controls in the micropylar region. To determine if the embryo must be in contact with the endosperm of SHAM to weaken the endosperm, some endosperms were incubated with SHAM only after dissection from seeds. Rupture strength of SHAM-treated, isolated endosperms in the micropylar region was 25% less than that of untreated controls. There was no difference in rupture strength in the cotyledonary region of endosperm isolated from seeds treated with SHAM in buffer or buffer alone. SHAM therefore stimulates germination not by enhancing embryo growth potential, but by weakening the micropylar region of the endosperm enclosing the embryo.

  6. The effects of cover crop on weed control in collard (Brassica olerecea var acephala) and lettuce (Lactuca sativa L.).

    Science.gov (United States)

    Mennan, H; Ngouajio, M; Isik, D; Kose, B; Kaya, E

    2006-01-01

    Leafy vegetables are not very competitive and weed interference can cause considerable yield losses in collard (Brassica olerecea var acephala) and lettuce (Lactuca sativa L.). Currently there are no pre or post emergence herbicides registered for weed control in these vegetables in Turkey. For this reason, alternative weed control strategies need to be developed. Cover crop residue could represent an alternative method of weed management in these crops. Field studies were conducted in 2004 at the Black Sea Agricultural Research Institute experimental field in Samsun, Turkey. The cover crop treatments consisted of Sorghum bicolor (L.) Moench, Sorghum vulgare Pers., Vicia villosa L., Amaranthus cruentus L., Pisum sativum L. and the bare ground with no cover crop. All cover crops were seeded by hand and incorporated into the soil on 11 May, 2004. Each plot was 10 m2 (2 x 5 m) and arranged in a randomized complete block design with four replications. All cover crops were incorporated into the soil by discing on 1 September 2004 at flowering stage of the cover crops. Broadleaved weed species were dominant in the experimental area. Most cover crops established well and S. bicolor biomass was the highest. The number of weed species emerging in all treatments was different at 14 DAD (days after desiccation). Similar results were observed at 28 and 56 DAD. Treatments with Vicia villosa residues had fewer weed species and lower total weed densities than other treatments.

  7. Effect of mycorrhiza on growth criteria and phosphorus nutrition of lettuce (Lactuca sativa L. under different phosphorus application rates

    Directory of Open Access Journals (Sweden)

    S. Fatih Ergin

    2016-10-01

    Full Text Available In this study, effect of mycorrhiza on growth criteria and phosphorus nutrition of lettuce (Lactuca sativa L. under different phosphorus fertilization rates were investigated. Phosphorus were added into growing media as 0, 50, 100 and 200 mg P2O5/kg with and without mycorrhiza applications. Phosphorus applications significantly increased yield criteria of lettuce according to the control treatment statistically. Mycorrhiza application also significantly increased plant diameter, plant dry weight and phosphor uptake by plant. The highest phosphorus uptakes by plants were determined in 200 mg P2O5/kg treatments as 88.8 mg P/pot with mycorrhiza and 83.1 mg P/pot without mycorrhiza application. In the control at 0 doses of phosphorus with mycorrhiza treatment, phosphorus uptake (69.9 mg P/pot, edible weight (84.36 g, dry weight (8.64 g and leaf number (28 of lettuce were higher than that (47.7 mg P/pot, 59.33 g, 6.75 g and 20, respectively in the control without mycorrhiza application. It was determined that mycorrhiza had positive effect on growth criteria and phosphorus nutrition by lettuce plant, and this effect decreased at higher phosphorus application rates.

  8. Qualidade da alface crespa minimamente processada acondicionada em atmosfera modificada Quality of minimally processed crisp head lettuce packaged under modified atmosphere

    Directory of Open Access Journals (Sweden)

    Rosana Mendes Roversi

    2004-08-01

    Full Text Available A alface Crespa (Lactuca sativa L.foi minimamente processada, tendo suas folhas destacadas e higienizadas, embalada em sacos plásticos de polietileno com modificação ativa da atmosfera dentro do pacote. Duas atmosferas foram aplicadas, variando-se o nível de CO2 em 10 e 15%, reduzindo nos dois casos o O2 a 5%. Após o acondicionamento, a alface foi imediatamente refrigerada. Comparou-se a qualidade da alface com e sem atmosfera modificada durante o armazenamento refrigerado. Monitoraram-se a variação da concentração de O2 e CO2 no interior das embalagens e a vida-útil da alface pela análise sensorial e microbiológica e a variação de sólidos solúveis. A influência da atmosfera modificada no crescimento de microrganismos e na variação de sólidos solúveis não foi relevante. Entretanto, essa tecnologia reduziu as taxas de respiração e, conseqüentemente, minimizou as perdas de qualidade sensorial da alface durante todo o armazenamento. A vida-útil da alface em atmosfera modificada foi estendida em até cinco dias além daquela alcançada pela alface acondicionada em atmosfera normal.The crisp head lettuce (Lactuca sativa L.was minimally processed, with the leaves being detached and cleaned, packaged in plastic bags made of polyethylene with modified atmosphere inside the bag. Two different atmospheres were applied: 10 and 15% of CO2, with the O2 level being reduced in both cases to 5%. After the packing, the lettuce was immediately refrigerated. The product quality with and without modified atmosphere was compared during the storage time. It was accompanied the changes in O2 and CO2 concentration inside the packaging and the product shelf life, through sensorial and microbiological analysis, and soluble solids variation. The influence of modified atmosphere in microorganisms grown and in soluble solids variation was not relevant. However this technology reduced the lettuce respiration rates and the quality sensorial loss

  9. Análisis técnico de producción de tilapia Oreochromis niloticus y lechuga acrópolis Lactuca sativa en acuaponia

    OpenAIRE

    Rubio Cabrera, Sheila Guadalupe

    2014-01-01

    Se evaluó la producción de tilapia Oreochromis niloticus y lechuga romana acropolis Lactuca sativa en sistemas acuapónicos utilizando dos sistemas: recirculación de agua sin recambio (utilizando biofiltración) y sistema sin recirculación con recambio parcial de agua. El cultivo se realizó en 4 etapas. En la primera se colocaron 800 alevines de O. niloticus de 0.2 g de peso inicial en tinas plásticas de 800 L (1600 organismos/m3de agua) durante 39 días. La segunda etapa con u...

  10. Influence of diesel contamination in soil on growth and dry matter partitioning of Lactuca sativa and Ipomoea batatas.

    Science.gov (United States)

    Fatokun, Kayode; Zharare, Godfrey Elijah

    2015-09-01

    Phytotoxic effect of diesel contaminated soil was investigated on growth and dry matter partitioning in Lactuca sativa and Ipomoea batatas in greenhouse pot experiment at two concentration range (0-30 ml and 0-6 ml diesel kg(-1) soil) for 14 weeks. The results indicated thatwhole plant biomass, stem length, root length, number of leaves and leaf chlorophyll in two plants were negatively correlated with increasing diesel concentrations. The critical concentration of diesel associated with 10% decrease in plant growth was 0.33 ml for lettuce and 1.50 ml for sweet potato. Thus, growth of lettuce in diesel contaminated soil was more sensitive than sweet potato. The pattern of dry matter partitioning between root and shoot in both plants were similar. In 0-6 ml diesel contamination range, allocation of dry matter to shoot system was favoured resulting in high shoot: root ratio of 4.54 and 12.91 for lettuce and sweet potato respectively. However, in 0-30 ml diesel contamination range, allocation of dry matter to root was favoured, which may have been an adaptive mechanism in which the root system was used for storage in addition to increasing the capacity for foraging for mineral nutrients and water. Although lettuce accumulated more metals in its tissue than sweet potato, the tissue mineral nutrients in both species did not vary to great extent. The critical diesel concentration for toxicity suggested that the cause of mortality and poor growth of sweet potato and lettuce grown in diesel contaminated soil was due to presence of hydrocarbons in diesel.

  11. Impact of non-functionalized and amino-functionalized multiwall carbon nanotubes on pesticide uptake by lettuce (Lactuca sativa L.).

    Science.gov (United States)

    Hamdi, Helmi; De La Torre-Roche, Roberto; Hawthorne, Joseph; White, Jason C

    2015-03-01

    The effect of non-functionalized and amino-functionalized multiwall carbon nanotube (CNT) exposure, as well as the impact of CNT presence on coexistent pesticide accumulation, was investigated in lettuce (Lactuca sativa L.). Lettuce seeds were sown directly into CNT-amended vermiculite (1000 mg L(-1)) to monitor phytotoxicity during germination and growth. During growth, lettuce seedlings were subsequently exposed to chlordane (cis-chlordane [CS], trans-chlordane [TC] and trans-nonachlor [TN]) and p,p'-DDE (all at 100 ng/L) in the irrigation solution for a 19-d growth period. CNT exposure did not significantly influence seed germination (82-96%) or plant growth. Similarly, pesticide exposure had no impact on plant growth, total pigment production or tissue lipid peroxidation. After 19 d, the root content of total chlordane and p,p'-DDE was 390 and 73.8 µg g(-1), respectively; in plants not exposed to CNTs, the shoot levels were 1.58 and 0.40 µg g(-1), respectively. The presence and type of CNT significantly influenced pesticide availability to lettuce seedlings. Non-functionalized CNT decreased the root and shoot pesticide content by 88% and 78%, respectively, but amino-functionalized CNT effects were significantly more modest, with decreases of 57% in the roots and 23% in the shoots, respectively. The presence of humic acid completely reversed the reduced accumulation of pesticides induced by amino-functionalized CNT, likely due to strong competition over adsorption sites on the nanomaterial (NM). These findings have implications for food safety and for the use of engineered NMs in agriculture, especially with leafy vegetables.

  12. Root exudation and root development of lettuce (Lactuca sativa L.cv. Tizian as affected by different soils

    Directory of Open Access Journals (Sweden)

    Günter eNeumann

    2014-01-01

    Full Text Available Development and activity of plant roots exhibits high adaptive variability. Although it is well-documented, that physicochemical soil properties can strongly influence root morphology and root exudation, particularly under field conditions, a comparative assessment is complicated by the impact of additional factors, such as climate and cropping history. To overcome these limitations, in this study, field soils originating from an unique experimental plot system with three different soil types, which were stored at the same field site for ten years and exposed to the same agricultural management practice, were used for an investigation on effects of soil type on root development and root exudation. Lettuce (Lactuca sativa L. cv. Tizian was used as a model plant, grown under controlled environmental conditions in a minirhizotrone system equipped with root observation windows (rhizoboxes. Root exudates were collected by placing sorption filters onto the root surface followed by subsequent extraction and GC-MS profiling of the trapped compounds. Surprisingly, even in absence of external stress factors with known impact on root exudation, such as pH extremes, water and nutrient limitations/toxicities or soil structure effects (use of sieved soils, root growth characteristics (root length, fine root development as well as profiles of root exudates were strongly influenced by the soil type used for plant cultivation. The results coincided well with differences in rhizosphere bacterial communities, detected in field-grown lettuce plants cultivated on the same soils (Schreiter et al., this issue. The findings suggest that the observed differences may be the result of plant interactions with the soil-specific microbiomes.

  13. Silencing the lettuce homologs of small rubber particle protein does not influence natural rubber biosynthesis in lettuce (Lactuca sativa).

    Science.gov (United States)

    Chakrabarty, Romit; Qu, Yang; Ro, Dae-Kyun

    2015-05-01

    Natural rubber, cis-1,4-polyisoprene, is an important raw material in chemical industries, but its biosynthetic mechanism remains elusive. Natural rubber is known to be synthesized in rubber particles suspended in laticifer cells in the Brazilian rubber tree (Hevea brasiliensis). In the rubber tree, rubber elongation factor (REF) and its homolog, small rubber particle protein (SRPP), were found to be the most abundant proteins in rubber particles, and they have been implicated in natural rubber biosynthesis. As lettuce (Lactuca sativa) can synthesize natural rubber, we utilized this annual, transformable plant to examine in planta roles of the lettuce REF/SRPP homologs by RNA interference. Among eight lettuce REF/SRPP homologs identified, transcripts of two genes (LsSRPP4 and LsSRPP8) accounted for more than 90% of total transcripts of REF/SRPP homologs in lettuce latex. LsSRPP4 displays a typical primary protein sequence as other REF/SRPP, while LsSRPP8 is twice as long as LsSRPP4. These two major LsSRPP transcripts were individually and simultaneously silenced by RNA interference, and relative abundance, polymer molecular weight, and polydispersity of natural rubber were analyzed from the LsSRPP4- and LsSRPP8-silenced transgenic lettuce. Despite previous data suggesting the implications of REF/SRPP in natural rubber biosynthesis, qualitative and quantitative alterations of natural rubber could not be observed in transgenic lettuce lines. It is concluded that lettuce REF/SRPP homologs are not critically important proteins in natural rubber biosynthesis in lettuce. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Bioavailability of silver and silver sulfide nanoparticles to lettuce (Lactuca sativa): Effect of agricultural amendments on plant uptake.

    Science.gov (United States)

    Doolette, Casey L; McLaughlin, Michael J; Kirby, Jason K; Navarro, Divina A

    2015-12-30

    Silver nanoparticles (AgNPs) can enter terrestrial systems as sulfidised AgNPs (Ag2S-NPs) through the application of biosolids to soil. However, the bioavailability of Ag2S-NPs in soils is unknown. The two aims of this study were to investigate (1) the bioavailability of Ag to lettuce (Lactuca sativa) using a soil amended with biosolids containing Ag2S-NPs and (2) the effect of commonly used agricultural fertilisers/amendments on the bioavailability of Ag, AgNPs and Ag2S-NPs to lettuce. The study used realistic AgNP exposure pathways and exposure concentrations. The plant uptake of Ag from biosolids-amended soil containing Ag2S-NPs was very low for all Ag treatments (0.02%). Ammonium thiosulfate and potassium chloride fertilisation significantly increased the Ag concentrations of plant roots and shoots. The extent of the effect varied depending on the type of Ag. Ag2S-NPs, the realistic form of AgNPs in soil, had the lowest bioavailability. The potential risk of AgNPs in soils is low; even in the plants that had the highest Ag concentrations (Ag(+)+thiosulfate), only 0.06% of added Ag was found in edible plant parts (shoots). Results from the study suggest that agricultural practises must be considered when carrying out risk assessments of AgNPs in terrestrial systems; such practises can affect AgNP bioavailability. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Experimental determinations of soil copper toxicity to lettuce (Lactuca sativa) growth in highly different copper spiked and aged soils.

    Science.gov (United States)

    Christiansen, Karen S; Borggaard, Ole K; Holm, Peter E; Vijver, Martina G; Hauschild, Michael Z; Peijnenburg, Willie J G M

    2015-04-01

    Accurate knowledge about factors and conditions determining copper (Cu) toxicity in soil is needed for predicting plant growth in various Cu-contaminated soils. Therefore, effects of Cu on growth (biomass production) of lettuce (Lactuca sativa) were tested on seven selected, very different soils spiked with Cu and aged for 2 months at 35 °C. Cu toxicity was expressed as pEC50(Cu(2+)), i.e., the negative logarithm of the EC50(Cu(2+)) activity to plant growth. The determined pEC50(Cu(2+)) was significantly and positively correlated with both the analytically readily available soil pH and concentration of dissolved organic carbon [DOC] which together could explain 87% of the pEC50(Cu(2+)) variation according to the simple equation: pEC50(Cu(2+)) = 0.98 × pH + 345 × [DOC] - 0.27. Other soil characteristics, including the base cation concentrations (Na(+), K(+), Ca(2+), Mg(2+)), the cation exchange capacity at soil pH (ECEC), and at pH 7 (CEC7), soil organic carbon, clay content, and electric conductivity as well as the distribution coefficient (Kd) calculated as the ratio between total soil Cu and water-extractable Cu did not correlate significantly with pEC50(Cu(2+)). Consequently, Cu toxicity, expressed as the negative log of the Cu(2+) activity, to plant growth increases at increasing pH and DOC, which needs to be considered in future management of plant growth on Cu-contaminated soils. The developed regression equation allows identification of soil types in which the phytotoxicity potential of Cu is highest.

  16. Root exudation and root development of lettuce (Lactuca sativa L. cv. Tizian) as affected by different soils

    Science.gov (United States)

    Neumann, G.; Bott, S.; Ohler, M. A.; Mock, H.-P.; Lippmann, R.; Grosch, R.; Smalla, K.

    2014-01-01

    Development and activity of plant roots exhibit high adaptive variability. Although it is well-documented, that physicochemical soil properties can strongly influence root morphology and root exudation, particularly under field conditions, a comparative assessment is complicated by the impact of additional factors, such as climate and cropping history. To overcome these limitations, in this study, field soils originating from an unique experimental plot system with three different soil types, which were stored at the same field site for 10 years and exposed to the same agricultural management practice, were used for an investigation on effects of soil type on root development and root exudation. Lettuce (Lactuca sativa L. cv. Tizian) was grown as a model plant under controlled environmental conditions in a minirhizotrone system equipped with root observation windows (rhizoboxes). Root exudates were collected by placing sorption filters onto the root surface followed by subsequent extraction and GC-MS profiling of the trapped compounds. Surprisingly, even in absence of external stress factors with known impact on root exudation, such as pH extremes, water and nutrient limitations/toxicities or soil structure effects (use of sieved soils), root growth characteristics (root length, fine root development) as well as profiles of root exudates were strongly influenced by the soil type used for plant cultivation. The results coincided well with differences in rhizosphere bacterial communities, detected in field-grown lettuce plants cultivated on the same soils (Schreiter et al., this issue). The findings suggest that the observed differences may be the result of plant interactions with the soil-specific microbiomes. PMID:24478764

  17. Foliar exposure of the crop Lactuca sativa to silver nanoparticles: Evidence for internalization and changes in Ag speciation

    Energy Technology Data Exchange (ETDEWEB)

    Larue, Camille, E-mail: camille.larue@rub.de [ISTerre, Université Grenoble 1, CNRS, F-38041 Grenoble (France); Castillo-Michel, Hiram, E-mail: castillo@esrf.fr [ESRF, Beamline ID21, Grenoble (France); Sobanska, Sophie, E-mail: sophie.sobanska@univ-lille1.fr [LASIR, UMR CNRS 8516, Université Lille 1, Bât C5, 59655 Villeneuve d’Ascq Cedex (France); Cécillon, Lauric, E-mail: lauric.cecillon@irstea.fr [ISTerre, Université Grenoble 1, CNRS, F-38041 Grenoble (France); Bureau, Sarah, E-mail: sarah.bureau@ujf-grenoble.fr [ISTerre, Université Grenoble 1, CNRS, F-38041 Grenoble (France); Barthès, Véronique, E-mail: veronique.barthes@cea.fr [CEA/LITEN/DTNM/L2T, CEA Grenoble, 38054 Grenoble Cedex 9 (France); Ouerdane, Laurent, E-mail: laurent.ouerdane@univ-pau.fr [LCABIE/IPREM-UMR 5254, Université de Pau et des Pays de l‘Adour, 64053 Pau Cedex 9 (France); Carrière, Marie, E-mail: marie.carriere@cea.fr [UMR E3 CEA-UJF/LAN, 38054 Grenoble Cedex 9 (France); Sarret, Géraldine, E-mail: geraldine.sarret@ujf-grenoble.fr [ISTerre, Université Grenoble 1, CNRS, F-38041 Grenoble (France)

    2014-01-15

    Highlights: • Ag-NPs are internalized inside lettuce leaves after foliar exposure to a suspension of Ag-NPs. • A classical washing process is inefficient at decreasing significantly Ag content. • Ag-NPs in plants undergo oxidation, and resulting ionic Ag are complexed with organic compounds including thiol-containing molecules. • Foliar exposure to Ag-NPs does not lead to detectable phytotoxicity symptoms. -- Abstract: The impact of engineered nanomaterials on plants, which act as a major point of entry of contaminants into trophic chains, is little documented. The foliar pathway is even less known than the soil-root pathway. However, significant inputs of nanoparticles (NPs) on plant foliage may be expected due to deposition of atmospheric particles or application of NP-containing pesticides. The uptake of Ag-NPs in the crop species Lactuca sativa after foliar exposure and their possible biotransformation and phytotoxic effects were studied. In addition to chemical analyses and ecotoxicological tests, micro X-ray fluorescence, micro X-ray absorption spectroscopy, time of flight secondary ion mass spectrometry and electron microscopy were used to localize and determine the speciation of Ag at sub-micrometer resolution. Although no sign of phytotoxicity was observed, Ag was effectively trapped on lettuce leaves and a thorough washing did not decrease Ag content significantly. We provide first evidence for the entrapment of Ag-NPs by the cuticle and penetration in the leaf tissue through stomata, for the diffusion of Ag in leaf tissues, and oxidation of Ag-NPs and complexation of Ag{sup +} by thiol-containing molecules. Such type of information is crucial for better assessing the risk associated to Ag-NP containing products.

  18. The allelopathic effects of invasive plant Solidago canadensis on seed germination and growth of Lactuca sativa enhanced by different types of acid deposition.

    Science.gov (United States)

    Wang, Congyan; Xiao, Hongguang; Zhao, Lulu; Liu, Jun; Wang, Lei; Zhang, Fei; Shi, Yanchun; Du, Daolin

    2016-04-01

    Invasive species can exhibit allelopathic effects on native species. Meanwhile, the types of acid deposition are gradually changing. Thus, the allelopathic effects of invasive species on seed germination and growth of native species may be altered or even enhanced under conditions with diversified acid deposition. This study aims to assess the allelopathic effects (using leaves extracts) of invasive plant Solidago canadensis on seed germination and growth of native species Lactuca sativa treated with five types of acid deposition with different SO4(2-) to NO3(-) ratios (1:0, sulfuric acid; 5:1, sulfuric-rich acid; 1:1, mixed acid; 1:5, nitric-rich acid; 0:1, nitric acid). Solidago canadensis leaf extracts exhibited significantly allelopathic effects on germination index, vigor index, and germination rate index of L. sativa. High concentration of S. canadensis leaf extracts also similarly exhibited significantly allelopathic effects on root length of L. sativa. This may be due to that S. canadensis could release allelochemicals and then trigger allelopathic effects on seed germination and growth of L. sativa. Acid deposition exhibited significantly negative effects on seedling biomass, root length, seedling height, germination index, vigor index, and germination rate index of L. sativa. This may be ascribed to the decreased soil pH values mediated by acid deposition which could produce toxic effects on seedling growth. Sulfuric acid deposition triggered more toxic effects on seedling biomass and vigor index of L. sativa than nitric acid deposition. This may be attributing to the difference in exchange capacity with hydroxyl groups (OH(-)) between SO4(2-) and NO3(-) as well as the fertilizing effects mediated by nitric deposition. All types of acid deposition significantly enhanced the allelopathic effects of S. canadensis on root length, germination index, vigor index, and germination rate index of L. sativa. This may be due to the negatively synergistic effects of

  19. An assessment of the role of ethylene in mediating lettuce (Lactuca sativa) root growth at high temperatures.

    Science.gov (United States)

    Qin, L; He, J; Lee, S K; Dodd, I C

    2007-01-01

    Growth of temperate lettuce (Lactuca sativa) plants aeroponically in tropical greenhouses under ambient root-zone temperatures (A-RZTs) exposes roots to temperatures of up to 40 degrees C during the middle of the day, and severely limits root and shoot growth. The role of ethylene in inhibiting growth was investigated with just-germinated (24-h-old) seedlings in vitro, and 10-d-old plants grown aeroponically. Compared with seedlings maintained at 20 degrees C, root elongation in vitro was inhibited by 39% and root diameter increased by 25% under a temperature regime (38 degrees C/24 degrees C for 7 h/17 h) that simulated A-RZT in the greenhouse. The effects on root elongation were partially alleviated by supplying the ethylene biosynthesis inhibitors aminooxyacetic acid (100-500 microM) or aminoisobutyric acid (5-100 microM) to the seedlings. Application of the ethylene precursor 1-aminocyclopropane-1-carboxylic acid to seedlings grown at 20 degrees C mimicked the high temperature effects on root elongation (1 microM) and root diameter (1 mM). Compared with plants grown at a constant 20 degrees C root-zone temperature, A-RZT plants showed decreased stomatal conductance, leaf relative water content, photosynthetic CO(2) assimilation, shoot and root biomass, total root length, the number of root tips, and root surface area, but increased average root diameter. Addition of 10 microM ACC to the nutrient solution of plants grown at a constant 20 degrees C root-zone temperature mimicked the effects of A-RZT on these parameters but did not influence relative water content. Addition of 30 microM aminoisobutyric acid or 100 microM aminooxyacetic acid to the nutrient solution of A-RZT plants increased stomatal conductance and relative water content and decreased average root diameter, but had no effect on other root parameters or root and shoot biomass or photosynthetic CO(2) assimilation. Although ethylene is important in regulating root morphology and elongation at A

  20. Dependence of plant biometrics of cutting lettuce (Lactuca sativa L. varietis on the concentration of microfertilizer Avatar-1

    Directory of Open Access Journals (Sweden)

    В. Б. Кутовенко

    2017-09-01

    Full Text Available Purpose. To investigate the variability of plant biometrics of cutting lettuce (Lactuca sativa L. varieties depending on the concentration of microfertilizer Avatar-1. Methods. Field study, biometric technique, comparative approach, statistical evaluation, generalization. Results. Dependence of the plant height, the diameter of the leaf rosette, the number of leaves per plant, the leaf area of plants on the concentration of microfertilizer Avatar-1 was defined. Investigations of cutting lettuce ‘Afitsyon’ and ‘Concord’ varieties by Dutch breeding were conducted in 2016–2017 in the collection sites of the department of vegetable growing in the scientific-experimental field  “Fruit and vegetable garden” of the National University of Life and Environmental Sciences of Ukraine. In order to determine dependence of plant biometrics of cutting lettuce varieties on the concentration of complex microfertilizer Avatar-1, the following scheme was used for the both varieties: variant 1 – water (control; variant 2 – 0,10% solution; variant 3 – 0,25% solution; variant 4 – 0,50% solution. Plants were treated with microfertilizer three times during the vegetative period. Alterations of plant biometrics of cutting lettuce ‘Afitsyon’ and ‘Concord’ varieties  depending on the concentration of complex microfertilizer Avatar-1 was studied. Conclusions. It was found that in case of three-time plant treatment with complex microfertilizer Avatar-1 at the time of harvesting, the best plant biometrics was registered in variant 3 (concentration 0,25% for the both ‘Afitsyon’ and ‘Concord’ varie­ties of cutting lettuce. The height of plants of the cutting lettuce in ‘Afitsyon’ variety exceeded this figure in ‘Concord variety by 1,1–1,4 cm. The concentration of microfertilizer had no significant effect on the diameter of the leaf rosette of ‘Concord’ variety (25,1–25,9 см. The diame­ter of the leaf rosette of

  1. Remote sensing of nutrient deficiency in Lactuca sativa using neural networks for terrestrial and advanced life support applications

    Science.gov (United States)

    Sears, Edie Seldon

    2000-12-01

    A remote sensing study using reflectance and fluorescence spectra of hydroponically grown Lactuca sativa (lettuce) canopies was conducted. An optical receiver was designed and constructed to interface with a commercial fiber optic spectrometer for data acquisition. Optical parameters were varied to determine effects of field of view and distance to target on vegetation stress assessment over the test plant growth cycle. Feedforward backpropagation neural networks (NN) were implemented to predict the presence of canopy stress. Effects of spatial and spectral resolutions on stress predictions of the neural network were also examined. Visual inspection and fresh mass values failed to differentiate among controls, plants cultivated with 25% of the recommended concentration of phosphorous (P), and those cultivated with 25% nitrogen (N) based on fresh mass and visual inspection. The NN's were trained on input vectors created using reflectance and test day, fluorescence and test day, and reflectance, fluorescence, and test day. Four networks were created representing four levels of spectral resolution: 100-nm NN, 10-nm NN, 1-nm NN, and 0.1-nm NN. The 10-nm resolution was found to be sufficient for classifying extreme nitrogen deficiency in freestanding hydroponic lettuce. As a result of leaf angle and canopy structure broadband scattering intensity in the 700-nm to 1000-nm range was found to be the most useful portion of the spectrum in this study. More subtle effects of "greenness" and fluorescence emission were believed to be obscured by canopy structure and leaf orientation. As field of view was not as found to be as significant as originally believed, systems implementing higher repetitions over more uniformly oriented, i.e. smaller, flatter, target areas would provide for more discernible neural network input vectors. It is believed that this technique holds considerable promise for early detection of extreme nitrogen deficiency. Further research is recommended using

  2. Health risks resulting from contaminants transfers in soil-plants systems: case study of Atrazine in Lactuca sativa.

    Science.gov (United States)

    Mathieu, Camoin

    2015-04-01

    Food safety is presently at the center of great part of scientific and political debates. This represents a field of study in its own right of health risks, including ingestion by humans of hazardous biological, physical, chemical or radiological substances, from contaminated foods during different stages of production. Plant cultivation step is often one of the main sources of contamination, whether of voluntary (pesticide application) or accidental (nuclear, industrial waste, etc.) origin. As a result, the plants growth in an contaminated environment may increase the risk of transfer within the plant, and finally the exposure of humans. Furthermore, pesticides are among the main contaminants investigated in the frame of human health risks resulting from food intakes. However, most of these scientific works focus mainly on their occurrence and persistence in water bodies, and few of them are interested in soil/plants transfer. In this context, the understanding of the processes governing transfers of pesticides in plants is become a necessity, in particular to prevent human risks linked the ingestion of food produced in contaminated environments. This objective can be reached by studying the pollutants behavior in soils/plants transfers, and using various substances/plants couples. In our study, we selected a salad/pesticide couple as our experimental model. Atrazine was chosen as model contaminant because of its problematic presence in a large amount of environmental compartments, its physico-chemical properties and because of its long-term toxicity. Lactuca sativa has been selected as model plant because of its importance in French agriculture, and specifically in Languedoc-Roussillon. Salad has been cultivated in peats and irrigated with an atrazine spiked water solution (concentrations from 10 to 100 μg/L). Plant growth in such conditions has been compared to a growth in clean condition (irrigation with non spiked water). Measurements of atrazine contents in

  3. EFEITO DO CLORO NA ÁGUA DE LAVAGEM PARA DESINFECÇÃO DE ALFACE MINIMAMENTE PROCESSADA

    Directory of Open Access Journals (Sweden)

    BERBARI Shirley Aparecida Garcia

    2001-01-01

    Full Text Available Este trabalho de pesquisa foi desenvolvido com o objetivo de verificar a eficácia de diferentes concentrações de cloro utilizadas como agente sanitizante na água de lavagem de alface(Lactuca sativa L., do tipo americana, minimamente processada. Na matéria-prima foram realizadas contagens de bolores, leveduras e coliformes totais. No produto final foram realizadas contagens de bolores e leveduras, coliformes totais e avaliação sensorial. O processamento mínimo da alface compreendeu as seguintes etapas: corte do talo, desfolhamento da cabeça, primeira seleção, primeira lavagem, segunda seleção, corte em tiras, segunda lavagem, tratamento de imersão em soluções contendo 70, 100 e 130mg/L de cloro, centrifugação, acondicionamento em sacos plásticos e armazenamento a 2°C e a 20°C. Os resultados mostraram que a imersão em solução contendo 70mg/L de cloro confere a alface minimamente processada uma vida-útil de seis dias e em solução contendo 100 e 130mg/L, nove dias e que o seu aroma, textura e gosto não foram afetados por estes tratamentos.

  4. Root adaptation and ion selectivity affects the nutritional value of salt-stressed hydroponically grown baby-leaf Nasturtium officinale and Lactuca sativa

    Directory of Open Access Journals (Sweden)

    Juan A. Fernández

    2016-12-01

    Full Text Available The response of watercress (Nasturtium officinale L. to salinity has been scarcely addressed in literature despite its growing importance in the baby-leaf market and its wide cultivation in salt-affected agricultural regions. This work evaluates the effect of salinity (2.5, 5 and 10 dS m-1 on productive and quality features of watercress compared with another crop widely cultivated for the baby-leaf sector (lettuce, Lactuca sativa. In watercress, a linear relationship (R2=0.75 was observed between yield decrease and Cl– accumulation in leaves, whereas yield was not affected by salinity in lettuce. NaCl application increased Na+ accumulation at the expense of Ca2+ uptake in the leaf tissues of both crops, but also of K+ in watercress. Health-related features were improved by salinity (e.g. increased phenolics and reduced nitrates, especially in watercress, with limited sensorial quality evaluation effects.

  5. 4,4,4-trifluoro-3-(indole-3-)butyric acid promotes root elongation in Lactuca sativa independent of ethylene synthesis and pH

    Science.gov (United States)

    Zhang, Nenggang; Hasenstein, Karl H.

    2002-01-01

    We studied the mode of action of 4,4,4-trifluoro-3- (indole-3-) butyric acid (TFIBA), a recently described root growth stimulator, on primary root growth of Lactuca sativa L. seedlings. TFIBA (100 micromoles) promoted elongation of primary roots by 40% in 72 h but inhibited hypocotyl growth by 35%. TFIBA induced root growth was independent of pH. TFIBA did not affect ethylene production, but reduced the inhibitory effect of ethylene on root elongation. TFIBA promoted root growth even in the presence of the ethylene biosynthesis inhibitor L-alpha-(2-aminoethoxyvinyl)glycine. TFIBA and the ethylene-binding inhibitor silver thiosulphate (STS) had a similar effect on root elongation. The results indicate that TFIBA-stimulated root elongation was neither pH-dependent nor related to inhibition of ethylene synthesis, but was possibly related to ethylene action.

  6. Allelopathic Activity of Extracts from Different Brazilian Peanut (Arachis hypogaeaL.) Cultivars on Lettuce(Lactuca sativa)and Weed Plants.

    Science.gov (United States)

    Casimiro, G S; Mansur, E; Pacheco, G; Garcia, R; Leal, I C R; Simas, N K

    2017-01-01

    Peanut ( Arachis hypogaea L.) is the fourth most consumed oleaginous plant in the world, producing seeds with high contents of lipids, proteins, vitamins, and carbohydrates. Biological activities of different extracts of this species have already been evaluated by many researchers, including antioxidant, antitumoral, and antibacterial. In this work, the allelopathic activity of extracts from different Brazilian peanut cultivars against lettuce (Lactuca sativa) and two weed plants ( Commelina benghalensis and Ipomoea nil ) was studied. Aerial parts, roots, seeds, and seed coats were used for the preparation of crude extracts. Seed extract partitioning was performed with n -hexane, dichloromethane, ethyl acetate, n -butanol, and aqueous residue. Germination and growth of hypocotyls and rootlets were evaluated after one and five days of incubation with plant extracts, respectively. Crude seed extract and its dichloromethanic partition displayed highest allelopathic activity. These results contribute for the study of new potential natural herbicides.

  7. Performance and feeding behaviour of two biotypes of the black currant-lettuce aphid, Nasonovia ribisnigri, on resistant and susceptible Lactuca sativa near-isogenic lines.

    Science.gov (United States)

    ten Broeke, Cindy J M; Dicke, Marcel; van Loon, Joop J A

    2013-10-01

    The black currant-lettuce aphid, Nasonovia ribisnigri, is an important pest of cultivated lettuce, Lactuca sativa. Since 1982, the control of this aphid on lettuce is largely based on host plant resistance, conferred by the Nr gene, introgressed from Lactuca virosa. The resistance mechanism remains to be identified. N. ribisnigri populations virulent on the Nr-based resistance in lettuce have emerged in several locations in Europe since 2007. The objective of this study was to investigate the resistance mechanism mediated by the Nr gene in lettuce by detailed studies of aphid feeding behaviour and performance. Both avirulent (Nr:0) and virulent (Nr:1)biotypes of N. ribisnigri were studied on five resistant and two susceptible near isogenic lines (NILs). In addition, survival and colony development were quantified.Nr:0 aphids showed a strong decrease in sieve element ingestion and took longer to accept a sieve element on resistant NILs compared with susceptible NILs, and no aphids survived on the resistant NIL. Nr:1 aphids fed and performed equally well on the resistant and susceptible NILs. The resistance mechanism against Nr:0 aphids encoded by the Nr gene seems to be located in the phloem, although we also observed differences in feeding behaviour during the pathway phase to the phloem. Nr:1 aphids were highly virulent to the resistance conferred by the Nr gene. The consequences of the appearance of Nr:1 aphids for control of N. ribisnigri are discussed.

  8. Combined effects of dissolved humic acids and tourmaline on the accumulation of 2, 2', 4, 4', 5, 5'- hexabrominated diphenyl ether (BDE-153) in Lactuca sativa.

    Science.gov (United States)

    Wang, Cuiping; Ma, Chuanxin; Jia, Weili; Wang, Dong; Sun, Hongwen; Xing, Baoshan

    2017-12-01

    In order to investigate the effects of dissolved humic acid (DHA) and tourmaline on uptake of 2, 2', 4, 4', 5, 5'- hexabrominated diphenyl ether (BDE-153) by Lactuca sativa, different fractions of DHA, including DHA 1 and DHA 4 , as well as different doses of tourmaline were introduced into BDE-153 contaminated solutions for plant growth. The levels of BDE-153 in L. sativa tissues were positively correlated with the Fe levels (R 2  = 0.9264) in seedings of the treatments with different doses of tourmaline. However, when adding DHA 1 and DHA 4 into the system, the correlation coefficients (R 2 ) decreased to 0.6976 and 0.5451 from 0.9264, respectively. In contrast with the Fe contents, the presence of DHAs didn't affect the R 2 between the levels of BDE-153 and the lipid contents in plant tissues. Our results indicated that both DHA 1 and DHA 4 could severely alter the BDE-153 uptake by L. sativa through reducing the Fe uptake instead of the lipid contents. Additionally, DHA 4 exhibited much stronger abilities to alter the BDE-153 accumulation than DHA 1 . Transmission electron microscopy (TEM) observations indicated that either DHA 1 or tourmaline or co-treatment with DHA and tourmaline had no negative impact on L. sativa at the cellular level. The present study provides important information for the impacts of different fractions of DHA extracted from soil on the BDE-153 migration in plant systems. Moreover, we elucidated the importance of the iron in tourmaline for migration of the polybrominated diphenyl ethers (PBDEs) in plant systems. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Accumulation of heavy metals by lettuce (lactuca sativa l.) irrigated with different levels of wastewater of Quetta City

    International Nuclear Information System (INIS)

    Achakzai, A.K.K.

    2011-01-01

    Heavy metal contamination of soils resulting from irrigation by wastewater is causing major concern due to the potential health risk involved. This study was therefore designed to investigate the heavy metal ions viz., Cu/sup 2/sup +/, Fe/sup 2+/, Mn/sup 2+/, Zn/sup 2+/, Pb/sup 2+/, Ni/sup 2+ and Cd/sup 2+/ concentrations by lettuce (Lactuca sativa L.) grown in pots. This leafy vegetable was irrigated with 5 different concentrations of wastewater collected from 3 different localities viz., Chiltan town, Chiltan Ghee Mill (oil industry) and Zarghoon town of Quetta city. Tap water was used as background water. Plant samples were analyzed for their heavy metal contents using Atomic Absorption Spectroscopy (AAS). Results showed that localities, treatments and their interactions (except Cu/sup 2+/ and Pb/sup 2+/) generally exhibited highly significant (P=0.01) influence on the accumulation of heavy metals. The maximum values of 9.71; 509.06; 32.47; 94.38; 8.58; 5.05 and 7.45 mg kg/sup -1/ for Cu/sup 2+/, total Fe/sup 2+/, Mn/sup 2+/, Zn/sup 2+/, Ni/sup 2+/,Pb/sup 2+/, and Cd/sup 2+/ respectively, were generally obtained in highest concentration of effluents. While maximum values of 9.02; 4.47 and 7.90 mg kg-1 of Cu/sup 2+/, Ni/sup 2+/ and Cd/sup 2+/ were obtained for Chiltan ghee mill effluents. However, maximum values i.e., 435.96 and 80.47 mg kg-1 of total Fe and Zn/sup 2+/ were recorded for Chiltan town. The highest values of 30.09 and 6.32 mg kg-1 for Mn/sup 2+/ and Pb/sup 2+/ were noted in Zarghoon town, respectively. On the basis of grand mean values,the magnitude of heavy metals detected for various metals is in order: Fe > Zn >Mn> Cu >Pb> Cd > Ni. Results further demonstrated that the total concentrations of Cu/sup 2+/, Fe/sup 2+/, Mn/sup 2+/, Zn/sup 2+/ and Ni/sup 2+/ are within the recommended international standards set by WHO/FAO, but could be reached to toxic level either by the consecutive use of effluents or by increased dietary pattern of the consumers

  10. Acclimation to UV-B radiation and visible light in Lactuca sativa involves up-regulation of photosynthetic performance and orchestration of metabolome-wide responses.

    Science.gov (United States)

    Wargent, J J; Nelson, B C W; McGhie, T K; Barnes, P W

    2015-05-01

    UV-B radiation is often viewed as a source of stress for higher plants. In particular, photosynthetic function has been described as a common target for UV-B impairment; yet as our understanding of UV-B photomorphogenesis increases, there are opportunities to expand the emerging paradigm of regulatory UV response. Lactuca sativa is an important dietary crop species and is often subjected to rapid sunlight exposure at field transfer. Acclimation to UV-B and visible light conditions in L. sativa was dissected using gas exchange and chlorophyll fluorescence measurements, in addition to non-destructive assessments of UV epidermal shielding (SUV ). After UV-B treatment, seedlings were subjected to wide-range metabolomic analysis using liquid chromatography hybrid quadrupole time-of-flight high-resolution mass spectrometry (LC-QTOF-HRMS). During the acclimation period, net photosynthetic rate increased in UV-treated plants, epidermal UV shielding increased in both subsets of plants transferred to the acclimatory conditions (UV+/UV- plants) and Fv /Fm declined slightly in UV+/UV- plants. Metabolomic analysis revealed that a key group of secondary compounds was up-regulated by higher light conditions, yet several of these compounds were elevated further by UV-B radiation. In conclusion, acclimation to UV-B radiation involves co-protection from the effects of visible light, and responses to UV-B radiation at a photosynthetic level may not be consistently viewed as damaging to plant development. © 2014 John Wiley & Sons Ltd.

  11. [Combination of phosphorus solubilizing and mobilizing fungi with phosphate rocks and volcanic materials to promote plant growth of lettuce (Lactuca sativa L.)].

    Science.gov (United States)

    Velázquez, María S; Cabello, Marta N; Elíades, Lorena A; Russo, María L; Allegrucci, Natalia; Schalamuk, Santiago

    Arbuscular mycorrhizal fungi (AMF) increase the uptake of soluble phosphates, while phosphorus solubilizing fungi (S) promote solubilization of insoluble phosphates complexes, favoring plant nutrition. Another alternative to maintaining crop productivity is to combine minerals and rocks that provide nutrients and other desirable properties. The aim of this work was to combine AMF and S with pyroclastic materials (ashes and pumices) from Puyehue volcano and phosphate rocks (PR) from Rio Chico Group (Chubut) - to formulate a substrate for the production of potted Lactuca sativa. A mixture of Terrafertil®:ashes was used as substrate. Penicillium thomii was the solubilizing fungus and Rhizophagus intraradices spores (AMF) was the P mobilizer (AEGIS® Irriga). The treatments were: 1) Substrate; 2) Substrate+AMF; 3) Substrate+S; 4) Substrate+AMF+S; 5) Substrate: PR; 6) Substrate: PR+AMF; 7) Substrate: PR+S and 8) Substrate: PR+AMF+S. Three replicates were performed per treatment. All parameters evaluated (total and assimilable P content in substrate, P in plant tissue and plant dry biomass) were significantly higher in plants grown in substrate containing PR and inoculas with S and AMF. This work confirms that the combination of S/AMF with Puyehue volcanic ashes, PR from the Río Chico Group and a commercial substrate promote the growth of L. sativa, thus increasing the added value of national geomaterials. Copyright © 2017 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  12. MECANISMOS DE AÇÃO DO EXTRATO AQUOSO DE Piper amalago EM CÉLULAS MERISTEMÁTICAS DE Lactuca sativa

    Directory of Open Access Journals (Sweden)

    Thammyres de Assis Alves

    2017-01-01

    Full Text Available Para manutenção da segurança alimentar o uso de agrotóxicos tem aumentado em todo o mundo, sendo o Brasil o seu maior consumidor desde 2009. Porém, os danos ambientais e à saúde humana, causados por essas substâncias sintéticas, tem provocado preocupações. Uma forma de amenizar o uso dos agrotóxicos é substituí-los totalmente ou em partes por compostos naturais, encontrados em plantas. Piper amalago é uma espécie que possui diferentes compostos químicos em sua constituição, tais como: alcaloides, amidos, terpenos e esteroides, o que determina nas suas diferentes atividades biológicas. Em virtude da sua constituição química, essa espécie é indicada para estudos de alelopatia. Assim, o presente trabalho objetivou avaliar o potencial mutagênico do extrato aquoso de P.  amalago através de bioensaio em Lactuca sativa. Para isso, análises de fitotoxicidade e citotoxicidade foram realizadas. Os dados obtidos foram submetidos ao teste de Dunnett com 5% de significância. Os resultados demonstram o potencial mutagênico do extrato aquoso de P. amalago em L. sativa, bem como, seus mecanismos de ação: clastogênicos e aneugênicos.

  13. Effect of SPL (Spent Pot Liner) and its main components on root growth, mitotic activity and phosphorylation of Histone H3 in Lactuca sativa L.

    Science.gov (United States)

    Freitas, Aline Silva; Fontes Cunha, Isabela Martinez; Andrade-Vieira, Larissa Fonseca; Techio, Vânia Helena

    2016-02-01

    Spent Pot Liner (SPL) is a solid waste from the aluminum industry frequently disposed of in industrial landfills; it can be leached and contaminate the soil, sources of drinking water and plantations, and thus may pose a risk to human health and to ecosystems. Its composition is high variable, including cyanide, fluoride and aluminum salts, which are highly toxic and environmental pollutants. This study evaluated the effect of SPL and its main components on root growth and the mitosis of Lactuca sativa, by investigating the mechanisms of cellular and chromosomal alterations with the aid of immunolocalization. To this end, newly emerged roots of L. sativa were exposed to SPL and its main components (solutions of cyanide, fluoride and aluminum) and to calcium chloride (control) for 48h. After this, root length was measured and cell cycle was examined by means of conventional cytogenetics and immunolocalization. Root growth was inhibited in the treatments with SPL and aluminum; chromosomal and nuclear alterations were observed in all treatments. The immunolocalization evidenced normal dividing cells with regular temporal and spatial distribution of histone H3 phosphorylation at serine 10 (H3S10ph). However, SPL and its main components inhibited the phosphorylation of histone H3 at serine 10, inactivated pericentromeric regions and affected the cohesion of sister chromatids, thus affecting the arrangement of chromosomes in the metaphase plate and separation of chromatids in anaphase. In addition, these substances induced breaks in pericentromeric regions, characterized as fragile sites. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Phytotoxicity of three plant-based biodiesels, unmodified castor oil, and Diesel fuel to alfalfa (Medicago sativa L.), lettuce (Lactuca sativa L.), radish (Raphanus sativus), and wheatgrass (Triticum aestivum).

    Science.gov (United States)

    Bamgbose, Ifeoluwa; Anderson, Todd A

    2015-12-01

    The wide use of plant-based oils and their derivatives, in particular biodiesel, have increased extensively over the past decade to help alleviate demand for petroleum products and improve the greenhouse gas emissions profile of the transportation sector. Biodiesel is regarded as a clean burning alternative fuel produced from livestock feeds and various vegetable oils. Although in theory these animal and/or plant derived fuels should have less environmental impact in soil based on their simplified composition relative to Diesel, they pose an environmental risk like Diesel at high concentrations when disposed. The aim of the present study was to ascertain the phytotoxicity of three different plant-derived biodiesels relative to conventional Diesel. For phytotoxicological analysis, we used seeds of four crop plants, Medicago sativa, Lactuca sativa, Raphanus sativus, and Triticum aestivum to analyze the germination of seeds in contaminated soil samples. The toxicological experiment was conducted with two different soil textures: sandy loam soil and silt loam soil. The studied plant-based biodiesels were safflower methyl-ester, castor methyl ester, and castor ethyl-ester. Biodiesel toxicity was more evident at high concentrations, affecting the germination and survival of small-seeded plants to a greater extent. Tolerance of plants to the biodiesels varied between plant species and soil textures. With the exception of R. sativus, all plant species were affected and exhibited some sensitivity to the fuels, such as delayed seedling emergence and slow germination (average=10 days) at high soil concentrations (0.85% for Diesel and 1.76% for the biodiesels). Tolerance of plants to soil contamination had a species-specific nature, and on average, decreased in the following order: Raphanus sativus (0-20%)>Triticum aestivum (10-40%) ≥ Medicago sativa> Lactuca sativa (80-100%). Thus, we conclude that there is some phytotoxicity associated with plant-based biodiesels. Further

  15. A chlorophyll fluorescence analysis of photosynthetic efficiency, quantum yield and photon energy dissipation in PSII antennae of Lactuca sativa L. leaves exposed to cinnamic acid.

    Science.gov (United States)

    Hussain, M Iftikhar; Reigosa, Manuel J

    2011-11-01

    This study investigated the effects of cinnamic acid (CA) on growth, biochemical and physiological responses of Lactuca sativa L. CA (0.1, 0.5, 1.0 and 1.5 mM) treatments decreased plant height, root length, leaf and root fresh weight, but it did not affect the leaf water status. CA treatment (1.5 mM) significantly reduced F(v), F(m), photochemical efficiency of PSII (F(v)/F(m)) and quantum yield of PSII (ΦPSII) photochemistry in L. sativa. The photochemical fluorescence quenching (qP) and non-photochemical quenching (NPQ) were reduced after treatment with 1.5 mM CA. Fraction of photon energy absorbed by PS II antennae trapped by "open" PS II reaction centers (P) was reduced by CA (1.5 mM) while, portion of absorbed photon energy thermally dissipated (D) and photon energy absorbed by PSII antennae and trapped by "closed" PSII reaction centers (E) was increased. Carbon isotope composition ratios (δ(13)C) was less negative (-27.10) in CA (1.5 mM) treated plants as compared to control (-27.61). Carbon isotope discrimination (Δ(13)C) and ratio of intercellular CO(2) concentration (ci/ca) from leaf to air were also less in CA treated plants. CA (1.5 mM) also decreased the leaf protein contents of L. sativa as compared to control. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

  16. Evaluation of analgesic, anti-inflammatory, anti-depressant and anti-coagulant properties of Lactuca sativa (CV. Grand Rapids) plant tissues and cell suspension in rats.

    Science.gov (United States)

    Ismail, Hammad; Mirza, Bushra

    2015-06-27

    Lactuca sativa (lettuce) has been traditionally used for relieving pain, inflammation, stomach problems including indigestion and lack of appetite. Moreover, the therapeutic significance of L. sativa includes its anticonvulsant, sedative-hypnotic and antioxidant properties. In the present study, the MC (methanol and chloroform; 1:1) and aqueous extracts of seed and leaf along with cell suspension exudate were prepared. These extracts were explored for their analgesic, anti-inflammatory, antidepressant and anticoagulant effects by hot plate analgesic assay; carrageenan induced hind paw edema test, forced swimming test and capillary method for blood clotting respectively in a rat model. The results were analyzed using one-way Analysis of Variance (ANOVA) followed by Turkey multiple comparison test. Interestingly, the extracts and the cell suspension exudate showed dual inhibition by reducing pain and inflammation. The results indicated that the aqueous extracts of leaf exhibited highest analgesic and anti-inflammatory activities followed by leaf MC, cell suspension exudate, seed aqueous and seed MC extracts. The current findings show that aqueous and MC extracts of seed have the least immobility time in the forced swimming test, which could act as an anti-depressant on the central nervous system. The leaf extracts and cell suspension exudate also expressed moderate anti-depressant activities. In anticoagulant assay, the coagulation time of aspirin (positive control) and MC extract of leaf was comparable, suggesting strong anti-coagulant effect. Additionally, no abnormal behavior or lethality was observed in any animal tested. Taken together, L. sativa can potentially act as a strong herbal drug due to its multiple pharmaceutical effects and is therefore of interest in drug discovery and development of formulations.

  17. Delineamento experimental e tamanho de amostra para alface cultivada em hidroponia Experimental design and sample size for hydroponic lettuce crop

    Directory of Open Access Journals (Sweden)

    Valéria Schimitz Marodim

    2000-10-01

    Full Text Available Este estudo visa a estabelecer o delineamento experimental e o tamanho de amostra para a cultura da alface (Lactuca sativa em hidroponia, pelo sistema NFT (Nutrient film technique. O experimento foi conduzido no Laboratório de Cultivos Sem Solo/Hidroponia, no Departamento de Fitotecnia da Universidade Federal de Santa Maria e baseou-se em dados de massa de plantas. Os resultados obtidos mostraram que, usando estrutura de cultivo de alface em hidroponia sobre bancadas de fibrocimento com seis canais, o delineamento experimental adequado é blocos ao acaso se a unidade experimental for constituída de faixas transversais aos canais das bancadas, e deve ser inteiramente casualizado se a bancada for a unidade experimental; para a variável massa de plantas, o tamanho da amostra é de 40 plantas para uma semi-amplitude do intervalo de confiança em percentagem da média (d igual a 5% e de 7 plantas para um d igual a 20%.This study was carried out to establish the experimental design and sample size for hydroponic lettuce (Lactuca sativa crop under nutrient film technique. The experiment was conducted in the Laboratory of Hydroponic Crops of the Horticulture Department of the Federal University of Santa Maria. The evaluated traits were plant weight. Under hydroponic conditions on concrete bench with six ducts, the most indicated experimental design for lettuce is randomised blocks for duct transversal plots or completely randomised for bench plot. The sample size for plant weight should be 40 and 7 plants, respectively, for a confidence interval of mean percentage (d equal to 5% and 20%.

  18. Effect of Ni and Urea on Growth, Nitrate and Nutrients Concentration in Lettuce (Lactuca sativa Grown in Hydroponics

    Directory of Open Access Journals (Sweden)

    Hosein Nazari Mamaqani

    2017-02-01

    Full Text Available Introduction: The N source used in commercial hydroponic culture of vegetables is mainly NO3-N. The rate of NO3- uptake is usually high, particularly in leafy vegetables and it can be markedly increased when the NO3- supply in the environment is high. An abundant N supply leads to a high NO3-N absorption and accumulation in plants. When NO3- rich vegetables are consumed, various harmful effects on human health may occur such as met-hemoglobinemia (Blue Baby Syndrome and cancer. Keeping levels of NO3- below limits of FAO seems to be impossible without changing conventional fertilizer application techniques. The suitability of urea for the cultivation of field crops has been well documented. Urea is used as the main source of N fertilizer for crops grown in soil. Its use as N source for crops grown under the hydroponic system has yet to be evaluated. To hydrolyze urea, the enzyme urease requires Ni as a component. Substitution of urea for commonly used N03-N fertilizers in hydroponic culture of vegetables would not only enable to avoid excessive accumulation of N03- in plants but would also reduce the cost of production. Leafy vegetable crops, such as lettuce and spinach, contain large amounts of N03-N. Therefore, it is important to reduce N03- concentrations in hydroponically grown with lowest negative effects on yield. Materials and Methods: The experiments were carried outin greenhouse hydroponicsResearchFaculty of Agriculture, University of Tabriz in randomized complete block designwithtwo factors ureaatfivelevels of 0,25, 50, 75and100milligrams perliter(U0, U25,U50, U75, U100andnickelattwo levels of0and2mg per liter (Ni0, Ni2ofnickelsulfate(NiSO4in4replicatesusinglettuce(Lactuca sativa cv. Siyahoo. Plants fed with the modifiedHoagland solutionorhalf theconcentration. Treatments added to nutrient solution when plants were in four leaf stage. Plants were harvested 50 days after treatment. Different organs (leaves, stems and roots were separated

  19. Role of ascorbic acid in the inhibition of polyphenol oxidase and the prevention of browning in different browning-sensitive Lactuca sativa var. capitata (L.) and Eruca sativa (Mill.) stored as fresh-cut produce.

    Science.gov (United States)

    Landi, Marco; Degl'Innocenti, Elena; Guglielminetti, Lorenzo; Guidi, Lucia

    2013-06-01

    Polyphenol oxidase (PPO) and, to a minor extent, peroxidase (POD) represent the key enzymes involved in enzymatic browning, a negative process induced by cutting fresh-cut produce such as lettuce (Lactuca sativa) and rocket salad (Eruca sativa). Although ascorbic acid is frequently utilised as an anti-browning agent, its mechanism in the prevention of the browning phenomenon is not clearly understood. The activity of PPO and POD and their isoforms in lettuce (a high-browning and low-ascorbic acid species) and rocket salad (a low-browning and high-ascorbic species) was characterised. The kinetic parameters of PPO and in vitro ascorbic acid-PPO inhibition were also investigated. In rocket salad, PPO activity was much lower than that in lettuce and cutting induced an increase in PPO activity only in lettuce. Exogenous ascorbic acid (5 mmol L(-1)) reduced PPO activity by about 90% in lettuce. POD did not appear to be closely related to browning in lettuce. PPO is the main enzyme involved in the browning phenomenon; POD appears to play a minor role. The concentration of endogenous ascorbic acid in rocket salad was related to its low-browning sensitivity after cutting. In lettuce, the addition of ascorbic acid directly inhibited PPO activity. The results suggest that the high ascorbic acid content found in rocket salad plays an effective role in reducing PPO activity. © 2012 Society of Chemical Industry.

  20. Root Zone Cooling and Exogenous Spermidine Root-Pretreatment Promoting Lactuca sativa L. Growth and Photosynthesis in the High-Temperature Season

    Directory of Open Access Journals (Sweden)

    Jin eSun

    2016-03-01

    Full Text Available Root zone high-temperature stress is a major factor limiting hydroponic plant growth during the high-temperature season. The effects of root zone cooling (RZC; at 25°C and exogenous spermidine (Spd root-pretreatment (SRP, 0.1 mM on growth, leaf photosynthetic traits, and chlorophyll fluorescence characteristics of hydroponic Lactuca sativa L. grown in a high-temperature season (average temperature > 30°C were examined. Both treatments significantly promoted plant growth and photosynthesis in the high-temperature season, but the mechanisms of photosynthesis improvement in the hydroponic grown lettuce plants were different between the RZC and SRP treatments. The former improved plant photosynthesis by increasing stoma conductance (Gs to enhance CO2 supply, thus promoting photosynthetic electron transport activity and phosphorylation, which improved the level of the photochemical efficiency of photosystem II (PSII, rather than enhancing CO2 assimilation efficiency. The latter improved plant photosynthesis by enhancing CO2 assimilation efficiency, rather than stomatal regulation. Combination of RZC and SRP significantly improved PN of lettuce plants in a high-temperature season by both improvement of Gs to enhance CO2 supply and enhancement of CO2 assimilation. The enhancement of photosynthetic efficiency in both treatments was independent of altering light-harvesting or excessive energy dissipation.

  1. Supplemental upward lighting from underneath to obtain higher marketable lettuce (Lactuca sativa leaf fresh weight by retarding senescence of outer leaves

    Directory of Open Access Journals (Sweden)

    Geng eZhang

    2015-12-01

    Full Text Available Recently, the so-called plant factory with artificial lighting (PFAL approach has been developed to provide safe and steady food production. Although PFALs can produce high-yielding and high-quality plants, the high plant density in these systems accelerates leaf senescence in the bottom (or outer leaves owing to shading by the upper (or inner leaves and by neighboring plants. This decreases yield and increases labor costs for trimming. Thus, the establishment of cultivation methods to retard senescence of outer leaves is an important research goal to improve PFAL yield and profitability. In the present study, we developed an LED lighting apparatus that would optimize light conditions for PFAL cultivation of a leafy vegetable. Lettuce (Lactuca sativa L. was hydroponically grown under white, red, or blue LEDs, with light provided from above (downward, with or without supplemental upward lighting from underneath the plant. White LEDs proved more appropriate for lettuce growth than red or blue LEDs, and the supplemental lighting retarded the senescence of outer leaves and decreased waste (i.e., dead or low-quality senescent leaves, leading to an improvement of the marketable leaf fresh weight.

  2. Standardized extract of Lactuca sativa Linn. and its fractions abrogates scopolamine-induced amnesia in mice: A possible cholinergic and antioxidant mechanism.

    Science.gov (United States)

    Malik, Jai; Kaur, Jagpreet; Choudhary, Sunayna

    2017-02-28

    The present study was designed to evaluate the efficacy of Lactuca sativa (LS) Linn. (Asteraceae) against scopolamine- induced amnesia and to validate its traditional claim as memory enhancer. Ethanol extract of fresh LS leaves (LSEE), standardized on the basis of quercetin content, was successively partitioned using various solvents viz., hexane, ethyl acetate, and n-butanol in increasing order of polarity. LSEE (50, 100, and 200 mg/kg) and its various fractions (at a dose equivalent to dose of LSEE exhibiting maximum activity), administered orally for 14 days, were evaluated for their memory enhancing effect against scopolamine-induced (1 mg/kg, i.p.) amnesia in 3-4 months old male Laca mice (n = 6 in each group). The memory enhancing effect was evaluated using behavioural (elevated plus maze, novel object recognition and Morris water maze tests) and biochemical parameters (acetylcholinesterase activity, malonaldehyde, superoxide dismutase, nitrite, catalase, and reduced gultathione content). The results of the test substances were compared with both scopolamine and donepezil that was used as a standard memory enhancer and acetylcholinesterase inhibitor. Scopolamine elicit marked deterioration of memory and alteration in biochemical parameters in comparison to the control group. LSEE and its n-butanol and aqueous fractions significantly (P memory impairment through its acetylcholinesterase inhibitory and antioxidant activity validating its traditional claim.

  3. Increased exposure to UV-B radiation during early development leads to enhanced photoprotection and improved long-term performance in Lactuca sativa.

    Science.gov (United States)

    Wargent, Jason J; Elfadly, Eslam M; Moore, Jason P; Paul, Nigel D

    2011-08-01

    Plant responses to solar UV radiation are numerous and have often been considered from a perspective of negative outcomes for plant productivity. In this study, we used two experimental approaches consisting of: (1) field-based spectrally modifying filters in addition to (2) controlled indoor exposure to UV-B, to examine the effects of UV radiation on growth and photosynthetic performance of lettuce (Lactuca sativa L.) seedlings. Various aspects of growth were affected in plants grown under a UV-inclusive environment compared to a UV-depleted environment, including reductions in leaf expansion, increases in leaf thickness and the rate of net photosynthesis. After transplantation to a uniform field environment, lettuce plants initially propagated under the UV-inclusive environment exhibited higher harvestable yields than those from a UV-depleted environment. In controlled conditions, photosynthetic rates were higher in plants grown in the presence of UV-B radiation, and relative growth of plants pre-acclimatized to UV-B was also increased, in addition to higher maximum photochemical efficiency of photosystem II (PSII) (F(v) /F(m) ) following subsequent exposure to high photosynthetically active radiation (PAR) and temperature stress. Our findings are discussed within the context of sustainability in agriculture and the paradigm shift in photobiology which such beneficial responses to UV radiation could represent. © 2011 Blackwell Publishing Ltd.

  4. Assembly of the Lactuca sativa, L. cv. Tizian draft genome sequence reveals differences within major resistance complex 1 as compared to the cv. Salinas reference genome.

    Science.gov (United States)

    Verwaaijen, Bart; Wibberg, Daniel; Nelkner, Johanna; Gordin, Miriam; Rupp, Oliver; Winkler, Anika; Bremges, Andreas; Blom, Jochen; Grosch, Rita; Pühler, Alfred; Schlüter, Andreas

    2018-02-10

    Lettuce (Lactuca sativa, L.) is an important annual plant of the family Asteraceae (Compositae). The commercial lettuce cultivar Tizian has been used in various scientific studies investigating the interaction of the plant with phytopathogens or biological control agents. Here, we present the de novo draft genome sequencing and gene prediction for this specific cultivar derived from transcriptome sequence data. The assembled scaffolds amount to a size of 2.22 Gb. Based on RNAseq data, 31,112 transcript isoforms were identified. Functional predictions for these transcripts were determined within the GenDBE annotation platform. Comparison with the cv. Salinas reference genome revealed a high degree of sequence similarity on genome and transcriptome levels, with an average amino acid identity of 99%. Furthermore, it was observed that two large regions are either missing or are highly divergent within the cv. Tizian genome compared to cv. Salinas. One of these regions covers the major resistance complex 1 region of cv. Salinas. The cv. Tizian draft genome sequence provides a valuable resource for future functional and transcriptome analyses focused on this lettuce cultivar. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Lettuce Production Hydroponics (Lactuca Sativa L. for the Promotion of Self-Management in Basic School Bolivariana “Los Naranjos”

    Directory of Open Access Journals (Sweden)

    Luis Alfredo Díaz

    2017-05-01

    Full Text Available The present research aims at the promotion of the Hydroponic Lettuce Cultivation (Lactuca Sativa L. as a self - management alternative in the Bolivarian Basic School “Los Naranjos”, Calderas parish, Bolívar municipality of Barinas state. The nature of the study is framed under the modality of the qualitative paradigm, adopting the method of Participatory Action Research. On the other hand, the research will be conducted in (4 four phases: Phase I. Diagnosis, Phase II. Elaboration of the action plan, Phase III. Implementation of the action plan, Phase IV. Reflection, interpretation and integration of results. Information triangulation was used to analyze the information in order to cross-check information from key informants. For all of the above, this study constitutes a significant contribution to the teaching and learning process as it is the responsibility of the family and teachers as promoters and agents of dissemination of knowledge, accept the responsibility in this process of placing children in contact And girls with new techniques of cultivation, in this case with the hydroponic technique, since its early years, so that this is a pleasurable, pleasant and encouraging experience that accompanies him for the rest of his life.

  6. Residual compost from the production of Bactris gasipaes Kunth and Pleurotus ostreatus as soil conditioners for Lactuca sativa ‘Veronica’

    Directory of Open Access Journals (Sweden)

    Marcelo Barba Bellettini

    2017-05-01

    Full Text Available This study evaluated the residual compost from the production of Bactris gasipaes Kunth (pupunha heart of palm (RP and the mushroom Pleurotus ostreatus (RM. The residuals were used as soil conditioners for Lactuca sativa ‘Veronica’ crops. After adding RP and RM to the soil, all treatments exhibited similar behaviors and soils in each treatment were classified as eutrophic. Soil treatments involving increased application of residual compost resulted in the production of lettuce with greater widths because of an increase in the angle between the stem and leaf, resulting from a lack of nitrogen available to the plant. Soil treatments with 5% of RP and RM resulted in a 1.7 and 1.2 times (44% and 22%, respectively decrease in dry weight of lettuce, as compared to the soil without residual compost addition. The addition of RP and RM as soil substrate reduced the growth of lettuce compared to the soil without residual compost. In general, the possibility of replacing chemical fertilizers (NPK with RP or RM without previous composting was found to be inefficient. The resultant dry weight parameters were below the commercial level, and a complete period of composting RP and RM was deemed necessary for incorporating nitrogen into the soil. Lignocellulosic mushrooms such as Pleurotus spp. present highly fibrous residual compost with low nitrogen content, thus requiring a full period of composting before subsequent use in soil enrichment for various crops.

  7. Influence of fine process particles enriched with metals and metalloids on Lactuca sativa L. leaf fatty acid composition following air and/or soil-plant field exposure

    International Nuclear Information System (INIS)

    Schreck, Eva; Laplanche, Christophe; Le Guédard, Marina; Bessoule, Jean-Jacques; Austruy, Annabelle; Xiong, Tiantian; Foucault, Yann; Dumat, Camille

    2013-01-01

    We investigate the effect of both foliar and root uptake of a mixture of metal(loid)s on the fatty acid composition of plant leaves. Our objectives are to determine whether both contamination pathways have a similar effect and whether they interact. Lactuca sativa L. were exposed to fine process particles enriched with metal(loid)s in an industrial area. Data from a first experiment were used to conduct an exploratory statistical analysis which findings were successfully cross-validated by using the data from a second one. Both foliar and root pathways impact plant leaf fatty acid composition and do not interact. Z index (dimensionless quantity), weighted product of fatty acid concentration ratios was built up from the statistical analyses. It provides new insights on the mechanisms involved in metal uptake and phytotoxicity. Plant leaf fatty acid composition is a robust and fruitful approach to detect and understand the effects of metal(loid) contamination on plants. -- Highlights: •The study compares foliar and root transfers of metal(loid)s and their effects on plants. •Field experiments are performed combining ecotoxicological and statistical analyses. •The use of leaf fatty acid composition is a relevant indicator of exposure pathway. •The uptake pathways are independent, with an additive effect in terms of phytotoxicity. -- Metal uptake via both foliar and root pathways alters in a distinctive manner the fatty acid composition of lettuce leaves

  8. Effect of acute ingestion of fresh and stored lettuce (Lactuca sativa) on plasma total antioxidant capacity and antioxidant levels in human subjects.

    Science.gov (United States)

    Serafini, Mauro; Bugianesi, Rossana; Salucci, Monica; Azzini, Elena; Raguzzini, Anna; Maiani, Giuseppe

    2002-12-01

    The present study investigated whether storage under modified-atmosphere packaging (MAP) affected the antioxidant properties of fresh lettuce (Lactuca sativa). Eleven healthy volunteers (six men, five women) consumed 250 g fresh lettuce, and blood was sampled before (0 h) and 2, 3 and 6 h after consumption. The protocol was repeated 3 d later with the same lettuce stored at 5 degrees C under MAP conditions (O2-N2 (5:95, v/v)). Results showed that after ingestion of fresh lettuce, plasma total radical-trapping antioxidant potential (TRAP), measured as area under the curve, was significantly higher (1.3 (sem 0.3) mmol/l per 6 h; Plettuce (0.1 (sem 0.2) mmol/l per 6 h). Plasma TRAP, quercetin and p-coumaric acid were significantly different from baseline values (Plettuce ingestion. Caffeic acid increased significantly at 3 h (Plettuce for all the measured markers. Our present results showed that ingestion of MAP-stored lettuce does not modify plasma redox status in healthy subjects. Further research is needed to develop post-harvesting techniques able to preserve the bioactive molecule content of plant food.

  9. Phytotoxic effects of leukamenin E (an ent-kaurene diterpenoid) on root growth and root hair development in Lactuca sativa L. seedlings.

    Science.gov (United States)

    Ding, Lan; Qi, Linlin; Jing, Hongwei; Li, Juan; Wang, Wei; Wang, Tao

    2008-11-01

    Leukamenin E, an ent-kaurene diterpenoid isolated from Isodon racemosa (Hemsl) Hara, showed phytotoxic effects on root growth and root hair development of lettuce seedlings (Lactuca sativa L.). Lower concentrations (10 microM) of leukamenin E did not affect root growth, but at concentrations higher than 50 microM, the rate was inhibited. The influence of leukamenin E on root growth rate was closely correlated with alterations in the mitotic index. A low incidence of aberrant mitosis image was observed when lettuce roots were treated with higher concentrations (100 and 200 microM) of leukamenin E. This suggests that inhibition of root growth may be due to inhibition of cell division. All tested concentrations of the diterpenoid (10 microM or more) inhibited root hair development in a dose-dependent manner. At a concentration of 80 microM, leukamenin E completely blocked root hair initiation. Application of Ag(+)-an ethylene action inhibitor-to lettuce seedlings inhibited root hair elongation similar to the diterpenoid. Enhanced root hair length was stimulated by exogenous ethephon-an ethylene-releasing agent-and could be reversed by addition of leukamenin E. This suggests that leukamenin E may act as a potential ethylene action antagonist in the inhibition of lettuce root hair development. We conclude that leukamenin E may curb root hair development by interfering with ethylene action at concentrations above 10 microM and inhibits root growth via inhibition of cell division at concentrations above 50 microM.

  10. Light-induced root hair formation in lettuce (Lactuca sativa L. cv. Grand Rapids) roots at low pH is brought by chlorogenic acid synthesis and sugar.

    Science.gov (United States)

    Narukawa, Megumi; Watanabe, Keiji; Inoue, Yasunori

    2010-11-01

    Previously, we reported that chlorogenic acid (CGA) facilitated root hair formation at pH 4.0 in lettuce (Lactuca sativa L. cv. Grand Rapids). Light was essential for this process. In the present study, we determined relationships between CGA, light, and sugar during root hair formation in lettuce seedlings. The amount of CGA increased with white light in intact seedlings. Exogenously applied CGA restored root hair formation in dark-grown intact seedlings at pH 4.0. However, no root hair formation was induced in decapitated seedlings regardless of light exposure and CGA application. Application of sucrose or glucose induced both root hair formation and CGA synthesis in light-grown decapitated seedlings at pH 4.0. Blue light was the most effective for both root hair formation and CGA synthesis when supplied with sucrose to decapitated seedlings. Addition of sucrose and CGA together induced root hair formation at pH 4.0 in dark-grown decapitated seedlings. Results suggest that light induced CGA synthesis from sugar in the roots. Sugar was also required for root hair formation other than starting material of CGA synthesis. In addition, an unknown low pH-induced factor was essential for lettuce root hair formation.

  11. Regulation of cell division and growth in roots of Lactuca sativa L. seedlings by the Ent-Kaurene diterpenoid rabdosin B.

    Science.gov (United States)

    Ding, Lan; Jing, Hongwei; Qin, Bo; Qi, Linlin; Li, Jing; Wang, Tao; Liu, Guoan

    2010-05-01

    Rabdosin B, an ent-kaurene diterpenoid purified from the air-dried aerial parts of Isodon japonica (Burm.f) Hara var. galaucocalyx (maxin) Hara, showed a biphasic, dose-dependent effect on root growth and a strong inhibitory effect on root hair development in lettuce seedlings (Lactuca sativa L.). Lower concentrations of rabdosin B (20-80 microM) significantly promoted root growth, but its higher levels at 120-200 microM, by contrast, had inhibitory effects. Additionally, all tested concentrations (10-40 microM) inhibited root hair development of seedlings in a dose-dependent manner. Further investigations on the underlying mechanism revealed that the promotion effect of rabdosin B at the lower concentrations resulted from increasing the cell length in the mature region and enhancing the mitotic activity of meristematic cells in seedlings' root tips. In contrast, rabdosin B at higher concentrations inhibited root growth by affecting both cell length in the mature region and division of meristematic cells. Comet assay and cell cycle analysis demonstrated that the decrease of mitotic activity of root meristematic cells was due to DNA damage induced cell cycle retardation of the G(2) phase and S phase at different times.

  12. Humic substances can modulate the allelopathic potential of caffeic, ferulic, and salicylic acids for seedlings of lettuce (Lactuca sativa L.) and tomato (Lycopersicon esculentum Mill.).

    Science.gov (United States)

    Loffredo, Elisabetta; Monaci, Linda; Senesi, Nicola

    2005-11-30

    The capacity of a leonardite humic acid (LHA), a soil humic acid (SHA), and a soil fulvic acid (SFA) in modulating the allelopathic potential of caffeic acid (CA), ferulic acid (FA), and salicylic acid (SA) on seedlings of lettuce (Lactuca sativa L.) and tomato (Lycopersicon esculentum Mill.) was investigated. Lettuce showed a sensitivity greater than that of tomato to CA, FA, and SA phytotoxicity, which was significantly reduced or even suppressed in the presence of SHA or SFA, especially at the highest dose, but not LHA. In general, SFA was slightly more active than SHA, and the efficiency of the action depended on their concentration, the plant species and the organ examined, and the allelochemical. The daily measured residual concentration of CA and FA decreased drastically and that of SA slightly in the presence of germinating seeds of lettuce, which were thus able to absorb and/or enhance the degradation of CA and FA. The adsorption capacity of SHA for the three allelochemicals was small and decreased in the order FA > CA > SA, thus suggesting that adsorption could be a relevant mechanism, but not the only one, involved in the "antiallelopathic" action.

  13. Production characteristics of lettuce Lactuca sativa L. in the frame of the first crop tests in the Higher Plant Chamber integrated into the MELiSSA Pilot Plant

    Science.gov (United States)

    Tikhomirova, Natalia; Lawson, Jamie; Stasiak, Michael; Dixon, Mike; Paille, Christel; Peiro, Enrique; Fossen, Arnaud; Godia, Francesc

    Micro-Ecological Life Support System Alternative (MELiSSA) is an artificial closed ecosystem that is considered a tool for the development of a bioregenerative life support system for manned space missions. One of the five compartments of MELiSSA loop -Higher Plant Chamber was recently integrated into the MELiSSA Pilot Plant facility at Universitat Aut`noma deo Barcelona. The main contributions expected by integration of this photosynthetic compartment are oxygen, water, vegetable food production and CO2 consumption. Production characteristics of Lactuca sativa L., as a MELiSSA candidate crop, were investigated in this work in the first crop experiments in the MELiSSA Pilot Plant facility. The plants were grown in batch culture and totaled 100 plants with a growing area 5 m long and 1 m wide in a sealed controlled environment. Several replicates of the experiments were carried out with varying duration. It was shown that after 46 days of lettuce cultivation dry edible biomass averaged 27, 2 g per plant. However accumulation of oxygen in the chamber, which required purging of the chamber, and decrease in the food value of the plants was observed. Reducing the duration of the tests allowed uninterrupted test without opening the system and also allowed estimation of the crop's carbon balance. Results of productivity, tissue composition, nutrient uptake and canopy photosynthesis of lettuce regardless of test duration are discussed in the paper.

  14. The Impact of Biochar Application on Soil Properties and Plant Growth of Pot Grown Lettuce (Lactuca sativa and Cabbage (Brassica chinensis

    Directory of Open Access Journals (Sweden)

    Stephan Haefele

    2013-05-01

    Full Text Available The effect of rice-husk char (potentially biochar application on the growth of transplanted lettuce (Lactuca sativa and Chinese cabbage (Brassica chinensis was assessed in a pot experiment over a three crop (lettuce-cabbage-lettuce cycle in Cambodia. The biochar was the by-product of a rice-husk gasification unit and consisted of 28.7% carbon (C by mass. Biochar application rates to potting medium of 25, 50 and 150 g kg−1 were used with and without locally available fertilizers (a mixture of compost, liquid compost and lake sediment. The rice-husk biochar used was slightly alkaline (pH 7.79, increased the pH of the soil, and contained elevated levels of some trace metals and exchangeable cations (K, Ca and Mg in comparison to the soil. The biochar treatments were found to increase the final biomass, root biomass, plant height and number of leaves in all the cropping cycles in comparison to no biochar treatments. The greatest biomass increase due to biochar additions (903% was found in the soils without fertilization, rather than fertilized soils (483% with the same biochar application as in the “without fertilization” case. Over the cropping cycles the impact was reduced; a 363% increase in biomass was observed in the third lettuce cycle.

  15. Growth and phenolic compounds of Lactuca sativa L. grown in a closed-type plant production system with UV-A, -B, or -C lamp.

    Science.gov (United States)

    Lee, Min-Jeong; Son, Jung Eek; Oh, Myung-Min

    2014-01-30

    The production of high-quality crops based on phytochemicals is a strategy for accelerating the practical use of plant factories. Previous studies have demonstrated that ultraviolet (UV) light is effective in improving phytochemical production. This study aimed to determine the effect of various UV wavelengths on growth and phenolic compound accumulation in lettuce (Lactuca sativa L.) grown in a closed-type plant production system. Seven days, 1 day and 0.25 day were determined as the upper limit of the irradiation periods for UV-A, -B, and -C, respectively, in the lettuce based on physiological disorders and the fluorescence parameter F(v)/F(m). Continuous UV-A treatment significantly induced the accumulation of phenolic compounds and antioxidants until 4 days of treatment without growth inhibition, consistent with an increase in phenylalanine ammonia lyase (PAL) gene expression and PAL activity. Repeated or gradual UV-B exposure yielded approximately 1.4-3.6 times more total phenolics and antioxidants, respectively, than the controls did 2 days after the treatments, although both treatments inhibited lettuce growth. Repeated UV-C exposure increased phenolics but severely inhibited the growth of lettuce plants. Our data suggest that UV irradiation can improve the accumulation of phenolic compounds with antioxidant properties in lettuce cultivated in plant factories. © 2013 Society of Chemical Industry.

  16. Investigating the ability of Pseudomonas fluorescens UW4 to reduce cadmium stress in Lactuca sativa via an intervention in the ethylene biosynthetic pathway.

    Science.gov (United States)

    Albano, Lucas J; Macfie, Sheila M

    2016-12-01

    A typical plant response to any biotic or abiotic stress, including cadmium (Cd), involves increased ethylene synthesis, which causes senescence of the affected plant part. Stressed plants can experience reduced ethylene and improved growth if they are inoculated with bacteria that have the enzyme ACC deaminase, which metabolizes the ethylene precursor ACC (1-aminocyclopropane-1-carboxylate). We investigated whether one such bacterium, Pseudomonas fluorescens UW4, reduces the production of ethylene and improves the growth of lettuce (Lactuca sativa) sown in Cd-contaminated potting material (PRO-MIX® BX). Plants were inoculated with the wild-type P. fluorescens UW4 or a mutant strain that cannot produce ACC deaminase. Cadmium-treated plants contained up to 50 times more Cd than did control plants. In noninoculated plants, Cd induced a 5-fold increase in ethylene concentration. The wild-type bacterium prevented Cd-induced reductions in root biomass but there was no relationship between Cd treatment and ethylene production in inoculated plants. In contrast, when the concentration of ethylene was plotted against the extent of bacterial colonization of the roots, increased colonization with wild-type P. fluorescens UW4 was associated with 20% less ethylene production. Ours is the first study to show that the protective effect of this bacterium is proportional to the quantity of bacteria on the root surface.

  17. Evaluation of anti-inflammatory activity and fast UHPLC-DAD-IT-TOF profiling of polyphenolic compounds extracted from green lettuce (Lactuca sativa L.; var. Maravilla de Verano).

    Science.gov (United States)

    Pepe, Giacomo; Sommella, Eduardo; Manfra, Michele; De Nisco, Mauro; Tenore, Gian Carlo; Scopa, Antonio; Sofo, Adriano; Marzocco, Stefania; Adesso, Simona; Novellino, Tiziana; Campiglia, Pietro

    2015-01-15

    Fresh cut vegetables represent a widely consumed food worldwide. Among these, lettuce (Lactuca sativa L.) is one of the most popular on the market. The growing interest for this "healthy" food is related to the content of bioactive compounds, especially polyphenols, that show many beneficial effects. In this study, we report the anti-inflammatory and antioxidant potential of polyphenols extracted from lettuce (var. Maravilla de Verano), in J774A.1 macrophages stimulated with Escherichia coli lipopolysaccharide (LPS). Lettuce extract significantly decreased reactive oxygen species, nitric oxide release, inducible nitric oxide synthase and cycloxygenase-2 expression. A detailed quali/quantitative profiling of the polyphenolic content was carried out, obtaining fast separation (10 min), good retention time and peak area repeatability, (RSD% 0.80 and 8.68, respectively) as well as linearity (R(2)⩾ 0.999) and mass accuracy (⩽ 5 ppm). Our results show the importance in the diet of this cheap and popular food for his healthy properties. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Metallic Nanoparticle (TiO2 and Fe3O4) Application Modifies Rhizosphere Phosphorus Availability and Uptake by Lactuca sativa.

    Science.gov (United States)

    Zahra, Zahra; Arshad, Muhammad; Rafique, Rafia; Mahmood, Arshad; Habib, Amir; Qazi, Ishtiaq A; Khan, Saud A

    2015-08-12

    Application of engineered nanoparticles (NPs) with respect to nutrient uptake in plants is not yet well understood. The impacts of TiO2 and Fe3O4 NPs on the availability of naturally soil-bound inorganic phosphorus (Pi) to plants were studied along with relevant parameters. For this purpose, Lactuca sativa (lettuce) was cultivated on the soil amended with TiO2 and Fe3O4 (0, 50, 100, 150, 200, and 250 mg kg(-1)) over a period of 90 days. Different techniques, such as scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), Raman, and Fourier transform infrared spectroscopy (FTIR) were used to monitor translocation and understand the possible mechanisms for phosphorus (P) uptake. The trends for P accumulation were different for roots (TiO2 > Fe3O4 > control) and shoots (Fe3O4 > TiO2 > control). Cystine and methionine were detected in the rhizosphere in Raman spectra. Affinities of NPs to adsorb phosphate ions, modifications in P speciation, and NP stress in the rhizosphere had possibly contributed to enhanced root exudation and acidification. All of these changes led to improved P availability and uptake by the plants. These promising results can help to develop an innovative strategy for using NPs for improved nutrient management to ensure food security.

  19. Linking the morphological and metabolomic response of Lactuca sativa L exposed to emerging contaminants using GC × GC-MS and chemometric tools.

    Science.gov (United States)

    Hurtado, Carlos; Parastar, Hadi; Matamoros, Víctor; Piña, Benjamín; Tauler, Romà; Bayona, Josep M

    2017-07-26

    The occurrence of contaminants of emerging concern (CECs) in irrigation waters (up to low μg L -1 ) and irrigated crops (ng g -1 in dry weight) has been reported, but the linkage between plant morphological changes and plant metabolomic response has not yet been addressed. In this study, a non-targeted metabolomic analysis was performed on lettuce (Lactuca sativa L) exposed to 11 CECs (pharmaceuticals, personal care products, anticorrosive agents and surfactants) by irrigation. The plants were watered with different CEC concentrations (0-50 µg L -1 ) for 34 days under controlled conditions and then harvested, extracted, derivatised and analysed by comprehensive two-dimensional gas chromatography coupled to a time-of-flight mass spectrometer (GC × GC-TOFMS). The resulting raw data were analysed using multivariate curve resolution (MCR) and partial least squares (PLS) methods. The metabolic response indicates that exposure to CECs at environmentally relevant concentrations (0.05 µg L -1 ) can cause significant metabolic alterations in plants (carbohydrate metabolism, the citric acid cycle, pentose phosphate pathway and glutathione pathway) linked to changes in morphological parameters (leaf height, stem width) and chlorophyll content.

  20. Root Zone Cooling and Exogenous Spermidine Root-Pretreatment Promoting Lactuca sativa L. Growth and Photosynthesis in the High-temperature Season.

    Science.gov (United States)

    Sun, Jin; Lu, Na; Xu, Hongjia; Maruo, Toru; Guo, Shirong

    2016-01-01

    Root zone high-temperature stress is a major factor limiting hydroponic plant growth during the high-temperature season. The effects of root zone cooling (RZC; at 25°C) and exogenous spermidine (Spd) root-pretreatment (SRP, 0.1 mM) on growth, leaf photosynthetic traits, and chlorophyll fluorescence characteristics of hydroponic Lactuca sativa L. grown in a high-temperature season (average temperature > 30°C) were examined. Both treatments significantly promoted plant growth and photosynthesis in the high-temperature season, but the mechanisms of photosynthesis improvement in the hydroponic grown lettuce plants were different between the RZC and SRP treatments. The former improved plant photosynthesis by increasing stoma conductance (G s) to enhance CO2 supply, thus promoting photosynthetic electron transport activity and phosphorylation, which improved the level of the photochemical efficiency of photosystem II (PSII), rather than enhancing CO2 assimilation efficiency. The latter improved plant photosynthesis by enhancing CO2 assimilation efficiency, rather than stomatal regulation. Combination of RZC and SRP significantly improved P N of lettuce plants in a high-temperature season by both improvement of G s to enhance CO2 supply and enhancement of CO2 assimilation. The enhancement of photosynthetic efficiency in both treatments was independent of altering light-harvesting or excessive energy dissipation.

  1. Particle trajectories in seeds of Lactuca sativa and chromosome aberrations after exposure to cosmic heavy ions on cosmos biosatellites 8 and 9

    Science.gov (United States)

    Facius, R.; Scherer, K.; Reitz, G.; Bücker, H.; Nevzgodina, L. V.; Maximova, E. N.

    1994-10-01

    The potentially specific importance of the heavy ions of the galactic cosmic radiation for radiation protection in manned spaceflight continues to stimulate in situ, i.e., spaceflight experiments to investigate their radiobiological properties. Chromosome aberrations as an expression of a direct assault on the genome are of particular interest in view of cancerogenesis being the primary radiation risk for man in space. In such investigations the establishment of the geometrical correlation between heavy ions' trajectories and the location of radiation sensitive biological substructures is an essential task. The overall qualitative and quantitative precision achieved for the identification of particle trajectories in the order of 2~10 μm as well as the contributing sources of uncertainties are discussed. We describe how this was achieved for seeds of Lactuca sativa as biological test organisms, whose location and orientation had to be derived from contact photographies displaying their outlines and those of the holder plates only. The incidence of chromosome aberrations in cells exposed during the COSMOS 1887 (Biosatellite 8) and the COSMOS 2044 (Biosatellite 9) mission was determined for seeds hit by cosmic heavy ions. In those seeds the incidence of both single and multiple chromosome aberrations was enhanced. The results of the Biosatellite 9 experiment, however, are confounded by spaceflight effects unrelated to the passage of heavy ions.

  2. Synthesis of Copper-Chelates Derived from Amino Acids and Evaluation of Their Efficacy as Copper Source and Growth Stimulator for Lactuca sativa in Nutrient Solution Culture.

    Science.gov (United States)

    Kaewchangwat, Narongpol; Dueansawang, Sattawat; Tumcharern, Gamolwan; Suttisintong, Khomson

    2017-11-15

    Five tetradentate ligands were synthesized from l-amino acids and utilized for the synthesis of Cu(II)-chelates 1-5. The efficacy of Cu(II)-chelates as copper (Cu) source and growth stimulator in hydroponic cultivation was evaluated with Lactuca sativa. Their stability test was performed at pH 4-10. The results suggested that Cu(II)-chelate 3 is the most pH tolerant complex. Levels of Cu, Zn, and Fe accumulated in plants supplied with Cu(II)-chelates were compared with those supplied with CuSO 4 at the same Cu concentration of 8.0 μM. The results showed that Cu(II)-chelate 3 significantly enhanced Cu, Zn, and Fe content in shoot by 35, 15, and 48%, respectively. Application of Cu(II)-chelate 3 also improved plant dry matter yield by 54%. According to the results, Cu(II)-chelate 3 demonstrated the highest stimulating effect on plant growth and plant mineral accumulation so that it can be used as an alternative to CuSO 4 for supplying Cu in nutrient solutions and enhancing the plant growth.

  3. Supplemental Upward Lighting from Underneath to Obtain Higher Marketable Lettuce (Lactuca sativa) Leaf Fresh Weight by Retarding Senescence of Outer Leaves.

    Science.gov (United States)

    Zhang, Geng; Shen, Shanqi; Takagaki, Michiko; Kozai, Toyoki; Yamori, Wataru

    2015-01-01

    Recently, the so-called "plant factory with artificial lighting" (PFAL) approach has been developed to provide safe and steady food production. Although PFALs can produce high-yielding and high-quality plants, the high plant density in these systems accelerates leaf senescence in the bottom (or outer) leaves owing to shading by the upper (or inner) leaves and by neighboring plants. This decreases yield and increases labor costs for trimming. Thus, the establishment of cultivation methods to retard senescence of outer leaves is an important research goal to improve PFAL yield and profitability. In the present study, we developed an LED lighting apparatus that would optimize light conditions for PFAL cultivation of a leafy vegetable. Lettuce (Lactuca sativa L.) was hydroponically grown under white, red, or blue LEDs, with light provided from above (downward), with or without supplemental upward lighting from underneath the plant. White LEDs proved more appropriate for lettuce growth than red or blue LEDs, and the supplemental lighting retarded the senescence of outer leaves and decreased waste (i.e., dead or low-quality senescent leaves), leading to an improvement of the marketable leaf fresh weight.

  4. Transformation of Lactuca sativa L. with rol C gene results in increased antioxidant potential and enhanced analgesic, anti-inflammatory and antidepressant activities in vivo.

    Science.gov (United States)

    Ismail, Hammad; Dilshad, Erum; Waheed, Mohammad Tahir; Sajid, Moniba; Kayani, Waqas Khan; Mirza, Bushra

    2016-12-01

    Lettuce is an important edible crop which possesses various medicinal properties. In this study Lactuca sativa L. (cv Grand Rapids) was transformed by Agrobacterium-mediated transformation with rol C gene. Transgene integration and expression was confirmed through PCR and semiquantitative RT-PCR. The transformed extracts were evaluated for their in vitro antioxidant and in vivo analgesic, anti-inflammatory and antidepressant activities in rats. The transformed plants showed 53-98 % increase in total phenolic and 45-58 % increase in total flavonoid contents compared with untransformed plants. Results of total reducing power and total antioxidant capacity exhibited 90-118 and 61-75 % increase in transformed plants, respectively. In contrast to control, DPPH, lipid peroxidation and DNA protection assay showed up to 37, 20 and 50 % enhancement in transformed plants, respectively. The extracts showed similar but significant enhancement behavior in hot plate analgesic and carrageenan-induced hind paw edema test. The transformed extracts showed 72.1 and 78.5 % increase for analgesic and anti-inflammatory activities, respectively. The transformants of rol C gene exhibited prominent antidepressant activity with 64-73 % increase compared with untransformed plants. In conclusion, the present work suggests that transformation with rol C gene can be used to generate lettuce with enhanced medicinally important properties, such as antioxidant, analgesic, anti-inflammatory and antidepressant potential.

  5. Allelopathic effects of aqueous extracts of leaves of tree marigold (Tithonia diversifolia (Hemsl. A. Gray on seed germination and seedling growth of lettuce (Lactuca sativa L.

    Directory of Open Access Journals (Sweden)

    José Alberto Laynez Garsaball

    2013-09-01

    Full Text Available Some chemical compounds released by plants can to control the presence of other plants in their environment both of their own species and different ones, allelopathy is an important factor in regulating the structure of plant communities, a better understanding of these relationships is critical for appropriate agricultural development. The objective was to determine the effects of aqueous extracts of leaves of tree marigold (Tithonia diversifolia on seed germination and seedling growth of lettuce (Lactuca sativa L. cultivar Parris Island. A 15% w/v extract was prepared with leaves of tree marigold gold, it was allowed to stand for 48 h. After, diluting extracts at 0.5, 1.0, 1.5 and 2.0% w/v were obtained and pH and electrical conductivity (S.cm-1 were determined. Sowing was carried out in trays covered with a double layer of absorbent paper on which were placed 25 seeds/tray. Irrigation was applied twice per day using leaf extracts. The control treatment received tap water. A randomized complete block design was used with four replications. Seedlings were harvested at 14 days after sowing. pH decreased and electrical conductivity increased with increases in the concentration of leaf extracts. The germination was negatively affected by extracts. A lowering effect was observed on the overall growth of lettuce seedlings.

  6. Crescimento de alface hidropônica sob diferentes intervalos de irrigação Hydroponic lettuce growth under differents irrigation intervals

    Directory of Open Access Journals (Sweden)

    Fábio Zanella

    2008-04-01

    Full Text Available O intervalo entre irrigações é um importante critério a ser observado durante o cultivo hidropônico de hortaliças. Nesse contexto, objetivou-se com este trabalho avaliar a produtividade de duas cultivares de alface (Lactuca sativa L., Regina 2000 e Lucy Brown sob três intervalos de irrigação. O experimento foi conduzido no Centro Universitário Luterano de Ji-Paraná (CEULJI/ULBRA, entre setembro e dezembro de 2006. Foram testados três intevalos entre irrigações: 5; 15 e 30 minutos. Cada tratamento constou de quatro repetições de cada cultivar, em delineamento inteiramente casualisado. Analisou-se o número de folhas.planta-1, a massa fresca e massa seca total de cada planta. O aumento no intervalo entre irrigações levou a uma menor produção da alface. Assim, o intervalo de 5 minutos entre irrigações promoveu o maior ganho de massa para as duas cultivares avaliadas.The interval among irrigations is an important criterion taken into account during the hidroponic cultivation of vegetables. Thus, the present work aimed to evaluate the productivity of two lettuce (Lactuca sativa L. cultivars, Regina 2000 and Lucy Brown, in three irrigations intervals. The experiment was carried out at the Centro Universitário Luterano de Ji-Paraná (CEULJ/ULBRA, from September to December 2006. Three intervals between irrigations were used: 5; 15 and 30 minutes. Each treatment had four replications of both cultivars, in a complete randomized outline. The number of leaves.plant-1, total fresh mass and total dry mass were analyzed. There was an increase of the lettuce production according to the increase of the irrigation interval. Thus, 5 minutes among irrigations promoted the greater gain of mass for both cultivars evaluated.

  7. Análise parasitológica em alfaces cultivadas em diferentes sistemas de produção

    Directory of Open Access Journals (Sweden)

    Juliana Santiago Santos

    2017-05-01

    Full Text Available O presente estudo analisou a contaminação parasitológica em alfaces crespas (Lactuca sativa cultivadas em diferentes sistemas de produção (convencional, orgânico e hidropônico, fornecidas por uma cooperativa de produtores da agricultura familiar, no município de Presidente Prudente, São Paulo. As coletas foram repetidas em intervalos semanais, durante um período cinco meses, totalizando 180 amostras de hortaliças (60 amostras de alface por tipo de produção. As folhas das alfaces foram lavadas com Extran MA 02 a 0.5% e o fluído resultante submetido às técnicas de sedimentação e de centrífugo-flutuação, para recuperação das estruturas parasitárias. Observou-se que do total de 180 amostras, 71 (39,4% estavam contaminadas por pelo menos uma estrutura parasitária, sendo 34 (47,9% das alfaces cultivadas no sistema hidropônico, 20 (28,2% no orgânico e 17 (23,9% no sistema convencional. Cistos de Entamoeba spp. foram as estruturas parasitárias mais frequentes nas hortaliças, com maior contagem de cistos naquelas produzidas no sistema hidropônico (p=0,003. Conclui-se que independentemente do sistema de cultivo (convencional, orgânico e hidropônico, existe a possibilidade de contaminação de alfaces por enteroparasitos. Medidas que propiciem a melhoria na qualidade higiênico-sanitária na produção, assim como a adequada higienização das verduras antes do consumo “in natura” podem ser importantes para a redução da contaminação e consequente transmissão de doenças parasitárias pelo consumo “in natura” de hortaliças.

  8. Selective toxin effects on faster and slower growing individuals in the formation of hormesis at the population level - A case study with Lactuca sativa and PCIB.

    Science.gov (United States)

    Belz, Regina G; Sinkkonen, Aki

    2016-10-01

    Natural plant populations have large phenotypic plasticity that enhances acclimation to local stress factors such as toxin exposures. While consequences of high toxin exposures are well addressed, effects of low-dose toxin exposures on plant populations are seldom investigated. In particular, the importance of 'selective low-dose toxicity' and hormesis, i.e. stimulatory effects, has not been studied simultaneously. Since selective toxicity can change the size distribution of populations, we assumed that hormesis alters the size distribution at the population level, and investigated whether and how these two low-dose phenomena coexist. The study was conducted with Lactuca sativa L. exposed to the auxin-inhibitor 2-(p-chlorophenoxy)-2-methylpropionic acid (PCIB) in vitro. In two separate experiments, L. sativa was exposed to 12 PCIB doses in 24 replicates (50 plants/replicate). Shoot/root growth responses at the population level were compared to the fast-growing (≥90% percentile) and the slow-growing subpopulations (≤10% percentile) by Mann-Whitney U testing and dose-response modelling. In the formation of pronounced PCIB hormesis at the population level, low-dose effects proved selective, but widely stimulatory which seems to counteract low-dose selective toxicity. The selectivity of hormesis was dose- and growth rate-dependent. Stimulation occurred at lower concentrations and stimulation percentage was higher among slow-growing individuals, but partly or entirely masked at the population level by moderate or negligible stimulation among the faster growing individuals. We conclude that the hormetic effect up to the maximum stimulation may be primarily facilitated by an increase in size of the most slow-growing individuals, while thereafter it seems that mainly the fast-growing individuals contributed to the observed hormesis at the population level. As size distribution within a population is related to survival, our study hints that selective effects on slow

  9. Impacts of major cations (K(+), Na (+), Ca (2+), Mg (2+)) and protons on toxicity predictions of nickel and cadmium to lettuce (Lactuca sativa L.) using exposure models.

    Science.gov (United States)

    Liu, Yang; Vijver, Martina G; Peijnenburg, Willie J G M

    2014-04-01

    Biotic ligand models (BLM) explicitly accounting for hypothetical interactions with biotic ligands and bioavailability as dictated by water chemistry have been developed for various metals and different organisms. It is only recently that BLMs for plants have received increasing attention. Lettuce is one of the most important vegetable crops in the world. This study investigated the impacts of Ca(2+), Mg(2+), K(+), Na(+) and pH, on acute toxicity of Ni and Cd to butter-head lettuce seedlings (Lactuca sativa L.). 4-day assays with the root elongation inhibition (REI) as the endpoint were performed in hydroponic solutions. Magnesium was found to be the sole cation significantly enhancing the median inhibition concentration (IC50) of Ni(2+) with increasing concentration. By incorporating the competitive effects of Mg(2+), the Ni-toxicity prediction was improved significantly as compared to the total metal model (TMM) and the free ion activity model (FIAM). The conditional stability constants derived from the Ni-BLM were log K MgBL = 2.86, log K NiBL = 5.1, and f NiBL (50%)  = 0.57. A slight downtrend was observed in the 4-d IC50 of Cd(2+) at increasing H(+) concentrations, but this tendency was not consistent and statistically significant (p = 0.07) over the whole range. The overall variations of Cd-toxicity within the tested Na(+), K(+), Ca(2+) and Mg(2+) concentration ranges were relatively small and not statistically significant. 80 % of lettuce REI by Cd could be explained using both TMM and FIAM instead of BLM in the present study. Thus, the mechanistically underpinned models for soil quality guidelines should be developed on a metal-specific basis across different exposure conditions.

  10. The use of nile tilapia ( Oreochromis niloticus) cultivation wastewater for the production of romaine lettuce ( Lactuca sativa L. var. longifolia) in water recirculation system

    Science.gov (United States)

    Effendi, Hefni; Wahyuningsih, Sri; Wardiatno, Yusli

    2017-10-01

    In the recirculation aquaponic system (RAS), fish farming waste was utilized as a nutrient for plant, minimizing the water need, reducing the waste disposal into the environment, and producing the fish and plant as well. The study aimed to examine the growth of romaine lettuce ( Lactuca sativa L. var. Longifolia) in aquaponic system without the addition of artificial nutrient. The nutrient relies solely on wastewater of nile tilapia ( Oreochromis niloticus) cultivation circulated continuously on the aquaponic system. The results showed that tilapia weight reached 48.49 ± 3.92 g of T3 (tilapia, romaine lettuce, and inoculated bacteria), followed by T2 (tilapia and romaine lettuce) and T1 (tilapia) of 47.80 ± 1.97 and 45.89 ± 1.10 g after 35 days of experiment. Tilapia best performance in terms of growth and production occurred at T3 of 3.96 ± 0.44 g/day, 12.10 ± 0.63 %/day, 96.11 ± 1.44 % and 1.60 ± 0.07 for GR, SGR, SR, and FCR, respectively. It is also indicated by better water quality characteristic in this treatment. Romaine lettuce harvests of T2 and T3 showed no significant difference, with the final weight of 61.87 ± 5.59 and 57.74 ± 4.35 g. Overall, the integration of tilapia fish farming and romaine lettuce is potentially a promising aquaponic system for sustainable fish and horticulture plant production.

  11. Arabidopsis R2R3-MYB transcription factor AtMYB60 functions as a transcriptional repressor of anthocyanin biosynthesis in lettuce (Lactuca sativa).

    Science.gov (United States)

    Park, Jong-Sug; Kim, Jung-Bong; Cho, Kang-Jin; Cheon, Choong-Ill; Sung, Mi-Kyung; Choung, Myoung-Gun; Roh, Kyung-Hee

    2008-06-01

    The MYB transcription factors play important roles in the regulation of many secondary metabolites at the transcriptional level. We evaluated the possible roles of the Arabidopsis R2R3-MYB transcription factors in flavonoid biosynthesis because they are induced by UV-B irradiation but their associated phenotypes are largely unexplored. We isolated their genes by RACE-PCR, and performed transgenic approach and metabolite analyses in lettuce (Lactuca sativa). We found that one member of this protein family, AtMYB60, inhibits anthocyanin biosynthesis in the lettuce plant. Wild-type lettuce normally accumulates anthocyanin, predominantly cyanidin and traces of delphinidin, and develops a red pigmentation. However, the production and accumulation of anthocyanin pigments in AtMYB60-overexpressing lettuce was inhibited. Using RT-PCR analysis, we also identified the complete absence or reduction of dihydroflavonol 4-reductase (DFR) transcripts in AtMYB60- overexpressing lettuce (AtMYB60-117 and AtMYB60-112 lines). The correlation between the overexpression of AtMYB60 and the inhibition of anthocyanin accumulation suggests that the transcription factorAtMYB60 controls anthocyanin biosynthesis in the lettuce leaf. Clarification of the roles of the AtMYB60 transcription factor will facilitate further studies and provide genetic tools to better understand the regulation in plants of the genes controlled by the MYB-type transcription factors. Furthermore, the characterization of AtMYB60 has implications for the development of new varieties of lettuce and other commercially important plants with metabolic engineering approaches.

  12. Leaf Morphology, Photosynthetic Performance, Chlorophyll Fluorescence, Stomatal Development of Lettuce (Lactuca sativa L.) Exposed to Different Ratios of Red Light to Blue Light.

    Science.gov (United States)

    Wang, Jun; Lu, Wei; Tong, Yuxin; Yang, Qichang

    2016-01-01

    Red and blue light are both vital factors for plant growth and development. We examined how different ratios of red light to blue light (R/B) provided by light-emitting diodes affected photosynthetic performance by investigating parameters related to photosynthesis, including leaf morphology, photosynthetic rate, chlorophyll fluorescence, stomatal development, light response curve, and nitrogen content. In this study, lettuce plants (Lactuca sativa L.) were exposed to 200 μmol⋅m(-2)⋅s(-1) irradiance for a 16 h⋅d(-1) photoperiod under the following six treatments: monochromatic red light (R), monochromatic blue light (B) and the mixture of R and B with different R/B ratios of 12, 8, 4, and 1. Leaf photosynthetic capacity (A max) and photosynthetic rate (P n) increased with decreasing R/B ratio until 1, associated with increased stomatal conductance, along with significant increase in stomatal density and slight decrease in stomatal size. P n and A max under B treatment had 7.6 and 11.8% reduction in comparison with those under R/B = 1 treatment, respectively. The effective quantum yield of PSII and the efficiency of excitation captured by open PSII center were also significantly lower under B treatment than those under the other treatments. However, shoot dry weight increased with increasing R/B ratio with the greatest value under R/B = 12 treatment. The increase of shoot dry weight was mainly caused by increasing leaf area and leaf number, but no significant difference was observed between R and R/B = 12 treatments. Based on the above results, we conclude that quantitative B could promote photosynthetic performance or growth by stimulating morphological and physiological responses, yet there was no positive correlation between P n and shoot dry weight accumulation.

  13. A Lettuce (Lactuca sativa) Homolog of Human Nogo-B Receptor Interacts with cis-Prenyltransferase and Is Necessary for Natural Rubber Biosynthesis*

    Science.gov (United States)

    Qu, Yang; Chakrabarty, Romit; Tran, Hue T.; Kwon, Eun-Joo G.; Kwon, Moonhyuk; Nguyen, Trinh-Don; Ro, Dae-Kyun

    2015-01-01

    Natural rubber (cis-1,4-polyisoprene) is an indispensable biopolymer used to manufacture diverse consumer products. Although a major source of natural rubber is the rubber tree (Hevea brasiliensis), lettuce (Lactuca sativa) is also known to synthesize natural rubber. Here, we report that an unusual cis-prenyltransferase-like 2 (CPTL2) that lacks the conserved motifs of conventional cis-prenyltransferase is required for natural rubber biosynthesis in lettuce. CPTL2, identified from the lettuce rubber particle proteome, displays homology to a human NogoB receptor and is predominantly expressed in latex. Multiple transgenic lettuces expressing CPTL2-RNAi constructs showed that a decrease of CPTL2 transcripts (3–15% CPTL2 expression relative to controls) coincided with the reduction of natural rubber as low as 5%. We also identified a conventional cis-prenyltransferase 3 (CPT3), exclusively expressed in latex. In subcellular localization studies using fluorescent proteins, cytosolic CPT3 was relocalized to endoplasmic reticulum by co-occurrence of CPTL2 in tobacco and yeast at the log phase. Furthermore, yeast two-hybrid data showed that CPTL2 and CPT3 interact. Yeast microsomes containing CPTL2/CPT3 showed enhanced synthesis of short cis-polyisoprenes, but natural rubber could not be synthesized in vitro. Intriguingly, a homologous pair CPTL1/CPT1, which displays ubiquitous expressions in lettuce, showed a potent dolichol biosynthetic activity in vitro. Taken together, our data suggest that CPTL2 is a scaffolding protein that tethers CPT3 on endoplasmic reticulum and is necessary for natural rubber biosynthesis in planta, but yeast-expressed CPTL2 and CPT3 alone could not synthesize high molecular weight natural rubber in vitro. PMID:25477521

  14. Effects of microcystin-LR, cylindrospermopsin and a microcystin-LR/cylindrospermopsin mixture on growth, oxidative stress and mineral content in lettuce plants (Lactuca sativa L.).

    Science.gov (United States)

    Freitas, Marisa; Azevedo, Joana; Pinto, Edgar; Neves, Joana; Campos, Alexandre; Vasconcelos, Vitor

    2015-06-01

    Toxic cyanobacterial blooms are documented worldwide as an emerging environmental concern. Recent studies support the hypothesis that microcystin-LR (MC-LR) and cylindrospermopsin (CYN) produce toxic effects in crop plants. Lettuce (Lactuca sativa L.) is an important commercial leafy vegetable that supplies essential elements for human nutrition; thus, the study of its sensitivity to MC-LR, CYN and a MC-LR/CYN mixture is of major relevance. This study aimed to assess the effects of environmentally relevant concentrations (1, 10 and 100 µg/L) of MC-LR, CYN and a MC-LR/CYN mixture on growth, antioxidant defense system and mineral content in lettuce plants. In almost all treatments, an increase in root fresh weight was obtained; however, the fresh weight of leaves was significantly decreased in plants exposed to 100 µg/L concentrations of each toxin and the toxin mixture. Overall, GST activity was significantly increased in roots, contrary to GPx activity, which decreased in roots and leaves. The mineral content in lettuce leaves changed due to its exposure to cyanotoxins; in general, the mineral content decreased with MC-LR and increased with CYN, and apparently these effects are time and concentration-dependent. The effects of the MC-LR/CYN mixture were almost always similar to the single cyanotoxins, although MC-LR seems to be more toxic than CYN. Our results suggest that lettuce plants in non-early stages of development are able to cope with lower concentrations of MC-LR, CYN and the MC-LR/CYN mixture; however, higher concentrations (100 µg/L) can affect both lettuce yield and nutritional quality. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. A lettuce (Lactuca sativa) homolog of human Nogo-B receptor interacts with cis-prenyltransferase and is necessary for natural rubber biosynthesis.

    Science.gov (United States)

    Qu, Yang; Chakrabarty, Romit; Tran, Hue T; Kwon, Eun-Joo G; Kwon, Moonhyuk; Nguyen, Trinh-Don; Ro, Dae-Kyun

    2015-01-23

    Natural rubber (cis-1,4-polyisoprene) is an indispensable biopolymer used to manufacture diverse consumer products. Although a major source of natural rubber is the rubber tree (Hevea brasiliensis), lettuce (Lactuca sativa) is also known to synthesize natural rubber. Here, we report that an unusual cis-prenyltransferase-like 2 (CPTL2) that lacks the conserved motifs of conventional cis-prenyltransferase is required for natural rubber biosynthesis in lettuce. CPTL2, identified from the lettuce rubber particle proteome, displays homology to a human NogoB receptor and is predominantly expressed in latex. Multiple transgenic lettuces expressing CPTL2-RNAi constructs showed that a decrease of CPTL2 transcripts (3-15% CPTL2 expression relative to controls) coincided with the reduction of natural rubber as low as 5%. We also identified a conventional cis-prenyltransferase 3 (CPT3), exclusively expressed in latex. In subcellular localization studies using fluorescent proteins, cytosolic CPT3 was relocalized to endoplasmic reticulum by co-occurrence of CPTL2 in tobacco and yeast at the log phase. Furthermore, yeast two-hybrid data showed that CPTL2 and CPT3 interact. Yeast microsomes containing CPTL2/CPT3 showed enhanced synthesis of short cis-polyisoprenes, but natural rubber could not be synthesized in vitro. Intriguingly, a homologous pair CPTL1/CPT1, which displays ubiquitous expressions in lettuce, showed a potent dolichol biosynthetic activity in vitro. Taken together, our data suggest that CPTL2 is a scaffolding protein that tethers CPT3 on endoplasmic reticulum and is necessary for natural rubber biosynthesis in planta, but yeast-expressed CPTL2 and CPT3 alone could not synthesize high molecular weight natural rubber in vitro. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  16. Calidad microbiológica y parasitológica de lechuga (Lactuca sativa y cilantro (Coriandrum sativum expendidos en la Parroquia Santa Rita, Aragua, Venezuela

    Directory of Open Access Journals (Sweden)

    Nirza Noguera Machado

    2016-10-01

    Full Text Available Las hortalizas aportan grandes beneficios para la salud debido a sus innumerables propiedades alimenticias; sin embargo, existe una gran variedad de factores que ponen en riesgo la calidad sanitaria de las mismas constituyéndose en vehículos para enfermedades de transmisión alimentaria (ETA. Por ello, se decidió evaluar la calidad microbiológica y parasitológica de dos hortalizas, lechuga (Lactuca sativa y cilantro (Coriandrum sativum expendidas en la Parroquia Santa Rita del Municipio Francisco Linares Alcántara (Aragua, Venezuela. Se analizaron un total de 20 muestras, 10 de cilantro y 10 de lechuga; la determinación microbiológica se realizó por la técnica del Número Más Probable y el análisis parasitológico, mediante observación directa, tinción de Kinyoun y la técnica de Faust. Los resultados mostraron la presencia de coliformes totales (1,1x104 NMP/g en el 100 % de las muestras. No se evidenció coliformes fecales en ninguna de las muestras. En relación al análisis parasitológico, se identificaron protozoarios intestinales, con mayor prevalencia de Blastocystis spp. y menor en helmintos. Los resultados demuestran el peligro potencial que representa el consumo de hortalizas frescas contaminadas para la salud pública. Se debe concientizar a la población sobre medidas sanitarias preventivas que deben aplicar antes del consumo e implementar medidas de control que mejoren las condiciones higiénicas en la cadena de comercialización.

  17. Predawn and high intensity application of supplemental blue light decreases the quantum yield of PSII and enhances the amount of phenolic acids, flavonoids, and pigments in Lactuca sativa.

    Science.gov (United States)

    Ouzounis, Theoharis; Razi Parjikolaei, Behnaz; Fretté, Xavier; Rosenqvist, Eva; Ottosen, Carl-Otto

    2015-01-01

    To evaluate the effect of blue light intensity and timing, two cultivars of lettuce [Lactuca sativa cv. "Batavia" (green) and cv. "Lollo Rossa" (red)] were grown in a greenhouse compartment in late winter under natural light and supplemental high pressure sodium (SON-T) lamps yielding 90 (±10) μmol m(-2) s(-1) for up to 20 h, but never between 17:00 and 21:00. The temperature in the greenhouse compartments was 22/11°C day/night, respectively. The five light-emitting diode (LED) light treatments were Control (no blue addition), 1B 06-08 (Blue light at 45 μmol m(-2) s(-1) from 06:00 to 08:00), 1B 21-08 (Blue light at 45 μmol m(-2) s(-1) from 21:00 to 08:00), 2B 17-19 (Blue at 80 μmol m(-2) s(-1) from 17:00 to 19:00), and 1B 17-19 (Blue at 45 μmol m(-2) s(-1) from 17:00 to 19:00). Total fresh and dry weight was not affected with additional blue light; however, plants treated with additional blue light were more compact. The stomatal conductance in the green lettuce cultivar was higher for all treatments with blue light compared to the Control. Photosynthetic yields measured with chlorophyll fluorescence showed different response between the cultivars; in red lettuce, the quantum yield of PSII decreased and the yield of non-photochemical quenching increased with increasing blue light, whereas in green lettuce no difference was observed. Quantification of secondary metabolites showed that all four treatments with additional blue light had higher amount of pigments, phenolic acids, and flavonoids compared to the Control. The effect was more prominent in red lettuce, highlighting that the results vary among treatments and compounds. Our results indicate that not only high light level triggers photoprotective heat dissipation in the plant, but also the specific spectral composition of the light itself at low intensities. However, these plant responses to light are cultivar dependent.

  18. Peculiarities of forming quality parameters of commercial products of cutting lettuce (Lactuca sativa var. capitata L. depending on the method of cultivation

    Directory of Open Access Journals (Sweden)

    Н. В. Лещук

    2017-06-01

    Full Text Available Purpose. To investigate features of commercial head quality formation in varieties of cutting lettuce (Lactuca sativa var. capitata L. for different growing methods. To study the influence of growing methods for cutting lettuce plants on the weight of commercial heads, indices of yield and quality of freshly harvested products. Methods. Field study, laboratory testing and statistical evaluation. Results. The results of studying peculiarities of head formation in such cutting lettuce varieties as ‘Godar’ (control, ‘Smuhlianka’, ‘Olzhych’ and ‘Dyvohrai’ were shown. Based on the results of phenological observations, the duration of interstage periods of growth and development of cutting lettuce plants was determined for the different growing methods. The model of cutting lettuce of capitata variety for different growing methods was presented in terms of biochemical parameters (content of dry matter, vitamin C, nitrates, amount of sugars. The influence of growing methods for cutting lettuce plants on the commercial head weight, indices of yield and quality of freshly harvested products was studied. Obtained results confirmed that in early ripening varie­ti­es the heads were smaller (150 g and not dense, in late ripening varieties they were large and dense, weight was 150–500 g. Freshly harvested commercial products of head lettuce in case of seedling cultivation was characterized by a slight increase in dry matter content by 0.15–0.29%. The corresponding pattern was observed for the total sugar content. Its amount was slightly higher: 1.3–1.9% in case of direct sowing and 1.6–1.9% – for seedlings cultivation. The content of ascorbic acid (vitamin C, mg/100 g was the highest in the ‘Dyvohrai’ variety despite of the method of growing. The largest quantity of nitrates in lettuce heads was in the inner stem (480 mg/kg, while in the middle of the head it was reduced to 110 mg/kg. Conclusions. Freshly harvested heads of

  19. Effect of aqueous and hydro-alcoholic extracts of lettuce (Lactuca sativa) seed on testosterone level and spermatogenesis in NMRI mice.

    Science.gov (United States)

    Ahangarpour, Akram; Oroojan, Ali Akbar; Radan, Maryam

    2014-01-01

    One of the considerable uses of lettuce (Lactuca sativa) seed in traditional medicine has been to reduce semen, sperm and sexuality. The aim of this study was to investigate the effects of aqueous and hydro-alcoholic extracts of lettuce seed on testosterone level and spermatogenesis. In this experimental study 24 adult male NMRI mice weighing 20-25gr were purchased. Animals were randomly divided into 4 groups: controls, hydro-alcoholic (200 mg/kg) and aqueous extracts (50, 100mg/kg). The extracts were injected intraperitoneally once a day for 10 consecutive days. 2 weeks after the last injection, the mice were anaesthetized by ether and after laparatomy blood was collected from the heart to determine testosterone by ELISA assay kit. Then testis and cauda epididymis of all animals were removed for analyzing testis morphology and sperm count and viability. Testis weight in hydro-alcoholic and aqueous extracts 100 mg/kg (p=0.001) and aqueous extract 50 mg/kg (p=0.008) groups was increased. Sperm viability in hydro-alcoholic (p=0.001) and aqueous extracts 50 (p=0.026), 100 mg/kg (p=0.045) groups was decreased, Also the results showed a significant decrease in sperm count in hydro-alcoholic (p=0.035) and aqueous extracts 50 mg/kg (p=0.006) groups in comparison with control group. Also there was a significant increase in serum level of testosterone in aqueous extract 50 mg/kg group in comparison with control (p=0.002) hydro-alcoholic (p=0.001) and aqueous extracts 100 mg/kg (p=0.003) groups. Present results demonstrated that hydro-alcoholic and aqueous 50 mg/kg extracts of lettuce seed have antispermatogenic effects, also aqueous extract 50 mg/kg increased serum level of testosterone in mice. Therefore we can suggest that lettuce seed could be a potential contraceptive agent. This article extracted from M.Sc. student research project. (Ali Akbar Oroojan).

  20. Influence of season growth, soils and irrigation water composition on the concentration of uranium in two lettuce (Lactuca sativa L.) varieties. Field experiments

    Science.gov (United States)

    Abreu, M. M.; Neves, O.; Marcelino, M.

    2012-04-01

    Former uranium mines areas are frequently the sources of environmental radionuclides problems even many years after the closure of mining operations. A concern for inhabitants from mining areas is the use of contaminated land or irrigation water for agriculture, and the potential transfer of metals from soils to vegetables, and to humans through the food chain. The main aim of this study was to compare the uranium concentration in lettuce (Lactuca sativa L. varieties Marady and Romana) grown in different seasons (autumn and summer) and exposed to high and low uranium concentrations both in irrigation water and agricultural soil. The content of uranium in irrigation water, soil (total and available fraction) and in lettuce leaf samples was analyzed in a certified laboratory. In the field experiments, two agricultural soils were divided into two plots (four replicates each); one of them was irrigated with uranium contaminated water (0.94 to 1.14 mg/L) and the other with uncontaminated water (< 0.02 mg/L). Irrigation with contaminated water together with highest soil uranium available concentration (10 to 13 mg/kg) had negative effects on both studied lettuce varieties, namely yield reduction (up to 53% and 87% in autumn and summer experiments, respectively) and increase of uranium leaf concentration (up to 1.4 and 7 fold in autumn and summer, respectively). Effect on lettuce yield was mainly due to the high soil salinity (1.01 to 6.31 mS/cm) as a consequence of high irrigation water electrical conductivity (up to 1.82 mS/cm) and low lettuce soil salinity tolerance (1 to 3 mS/cm). The highest lettuce uranium concentration (dry weight) observed was 2.13 and 5.37 mg/kg for Marady and Romana variety, respectively. The highest uranium lettuce concentration in Romana variety was also the effect of its growing in summer season when it was subject to greatest frequency and amount of water irrigation. The consumption by an adult of the lettuce that concentrate more uranium

  1. The Rhizoctonia solani AG1-IB (isolate 7/3/14) transcriptome during interaction with the host plant lettuce (Lactuca sativa L.).

    Science.gov (United States)

    Verwaaijen, Bart; Wibberg, Daniel; Kröber, Magdalena; Winkler, Anika; Zrenner, Rita; Bednarz, Hanna; Niehaus, Karsten; Grosch, Rita; Pühler, Alfred; Schlüter, Andreas

    2017-01-01

    The necrotrophic pathogen Rhizoctonia solani is one of the most economically important soil-borne pathogens of crop plants. Isolates of R. solani AG1-IB are the major pathogens responsible for bottom-rot of lettuce (Lactuca sativa L.) and are also responsible for diseases in other plant species. Currently, there is lack of information regarding the molecular responses in R. solani during the pathogenic interaction between the necrotrophic soil-borne pathogen and its host plant. The genome of R. solani AG1-IB (isolate 7/3/14) was recently established to obtain insights into its putative pathogenicity determinants. In this study, the transcriptional activity of R. solani AG1-IB was followed during the course of its pathogenic interaction with the host plant lettuce under controlled conditions. Based on visual observations, three distinct pathogen-host interaction zones on lettuce leaves were defined which covered different phases of disease progression on tissue inoculated with the AG1-IB (isolate 7/3/14). The zones were defined as: Zone 1-symptomless, Zone 2-light brown discoloration, and Zone 3-dark brown, necrotic lesions. Differences in R. solani hyphae structure in these three zones were investigated by microscopic observation. Transcriptional activity within these three interaction zones was used to represent the course of R. solani disease progression applying high-throughput RNA sequencing (RNA-Seq) analysis of samples collected from each Zone. The resulting three transcriptome data sets were analyzed for their highest expressed genes and for differentially transcribed genes between the respective interaction zones. Among the highest expressed genes was a group of not previously described genes which were transcribed exclusively during early stages of interaction, in Zones 1 and 2. Previously described importance of up-regulation in R. solani agglutinin genes during disease progression could be further confirmed; here, the corresponding genes exhibited

  2. Lactucaxanthin - a potential anti-diabetic carotenoid from lettuce (Lactuca sativa) inhibits α-amylase and α-glucosidase activity in vitro and in diabetic rats.

    Science.gov (United States)

    Gopal, Sowmya Shree; Lakshmi, Magisetty Jhansi; Sharavana, Gurunathan; Sathaiah, Gunaseelan; Sreerama, Yadahally N; Baskaran, Vallikannan

    2017-03-22

    Intestinal and pancreatic α-amylase and α-glucosidase inhibitors offer an approach to lower the levels of post-prandial hyperglycemia through the control of dietary starch breakdown in digestion. This study hypothesized that lactucaxanthin (Lxn) in lettuce (Lactuca sativa) inhibits the activity of α-amylase and α-glucosidase. In this study, the interaction of Lxn with α-amylase and α-glucosidase in silico and its inhibitory effect on these enzymes were studied using in vitro and STZ-induced diabetic rat models. Lxn was isolated from lettuce with 96% purity confirmed by HPLC and LCMS. The in silico analysis showed that Lxn has a lower binding energy (-6.05 and -6.34 kcal mol -1 ) with α-amylase and α-glucosidase compared to their synthetic inhibitors, acarbose (-0.21 kcal mol -1 ) and miglitol (-2.78 kcal mol -1 ), respectively. In vitro α-amylase and α-glucosidase inhibition assays revealed that Lxn had IC 50 values of 435.5 μg mL -1 and 1.84 mg mL -1 , but acarbose has values of 2.5 and 16.19 μg mL -1 . The in vivo results showed an increased activity for α-amylase and α-glucosidase in the intestine (4.7 and 1.30 fold, p < 0.05) and pancreas (1.3 and 1.48 fold, p < 0.05) of STZ induced diabetic rats compared to normal rats. Whereas the activity decreased (p < 0.05) in the Lxn fed diabetic rats, except for the intestinal α-glucosidase activity (1.69 ± 0.12 PNP per min per mg protein). This was confirmed by the low blood glucose level (239.4 ± 18.2 mg dL -1 ) in diabetic rats fed Lxn compared to the diabetic group (572.2 ± 30.5 mg dL -1 , p < 0.05). Lxn significantly inhibited (p < 0.05) the activity of α-amylase and α-glucosidase and could be of medical and nutritional relevance in the treatment of diabetes.

  3. Potencial fitotóxico com enfoque alelopático de Bauhinia ungulata L. sobre sementes e plântulas de alface e cebola

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    Cristiane Silva Paula

    2016-07-01

    Full Text Available O presente trabalho avaliou o efeito do extrato etanólico e diferentes frações das folhas de Bauhinia ungulata L. sobre a germinação, crescimento, respiração e conteúdo de clorofila de plântulas de Lactuca sativa (alface e Allium cepa (cebola. Sementes de alface e cebola foram mantidas em contato com solução das amostras e colocadas em câmara de germinação. Realizaram-se contagens diárias para avaliar a interferência sobre a germinação e crescimento, e verificou-se possíveis interferências sobre a respiração radicular e o conteúdo de clorofila total das folhas das plântulas. Não foi observada nenhuma interferência das amostras sobre a porcentagem de germinação e massa seca das duas espécies. Com relação ao IVG, houve um atraso da germinação das sementes de alface quando em contato com o EB. O crescimento radicular das duas espécies foi inibido principalmente pelas frações EB e FR, sem nenhuma interferência sobre o crescimento do hipocótilo da alface e estímulo do crescimento do coleóptilo da cebola. Redução nos teores de clorofila total da alface e aumento na cebola, assim como estímulo da respiração das raízes. Conclui-se que o extrato e as frações de Bauhinia ungulata L. apresentam compostos químicos com atividade fitotóxica sobre o desenvolvimento de plântulas de alface interferindo principalmente no crescimento radicular, teor de clorofila e respiração radicular das espécies avaliadas.Palavras-chave: Fabaceae. Germinação. Clorofila. Sementes. Pata de Vaca. ABSTRACTPhytotoxic potential with allelopathic focus of Bauhinia ungulata L. on seeds and seedlings of lettuce and onionThis study evaluated the effect of ethanol extract and different fractions of leaves of Bauhinia ungulata L. on germination, growth, respiration and chlorophyll content of seedlings of Lactuca sativa (lettuce and Allium cepa (onion. Seeds of lettuce and onions were put in contact with the sample solution and placed

  4. Cobertura morta do solo no cultivo de alface cv. Regina 2000, em Ji-Paraná/RO Mulching in lettuce cv. Regina 2000, in Ji-Paraná/RO

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    Jimmy Elizio de Carvalho

    2005-10-01

    Full Text Available Conduziu-se este estudo com o objetivo de avaliar o efeito de diferentes materiais de cobertura do solo na produtividade da alface (Lactuca sativa L. cv. Regina 2000. O delineamento experimental utilizado foi o de blocos casualizados, utilizando-se cinco tratamentos (palha de arroz, palha de café, Brachiaria brizantha L., serragem, testemunha sem cobertura morta e quatro repetições. A produtividade foi avaliada pelo número de folhas por planta, acúmulo de massa fresca e massa seca. Verificou-se que todos os materiais empregados como cobertura, controlaram a infestação de plantas invasoras. Entretanto, verificou-se uma grande infestação na testemunha promovendo redução de produtividade.The purpose of this research was to evaluate the effect of different mulching materials on lettuce (Lactuca sativa L. cv. Regina 2000 yield. The experimental design was randomized blocks, with five treatments (rice straw, coffee husk, Brachiaria brizantha L., sawing and control without mulching and four repetitions. The number of leaves per plant and the dry and fresh matter accumulation were evaluated. All materials used as mulching, controlled the weed infestation. However, weed population was greater in the control whit reduction yield in comparison to the others treatments.

  5. Genetic diversity and evolution in Lactuca L. (Asteraceae)

    NARCIS (Netherlands)

    Wei, Z.

    2016-01-01

    Cultivated lettuce (Lactuca sativa L.) is an important leafy vegetable worldwide. However, the phylogenetic relationships between domesticated lettuce and its wild relatives are still not clear. In this thesis, I focus on the phylogenetic relationships within Lactuca L., including an analysis of the

  6. Genetic diversity and evolution in Lactuca L. (Asteraceae)

    NARCIS (Netherlands)

    Wei, Z.

    2016-01-01

    Cultivated lettuce (Lactuca sativa L.) is an important leafy vegetable worldwide. However, the phylogenetic relationships between domesticated lettuce and its wild relatives are still not clear. In this thesis, I focus on the phylogenetic relationships within Lactuca L.,

  7. Di-and tri-hydroxylated Kaurane derivatives from microbial transformation of Ent-Kaur-16-En-19-Ol by Cephalosporium aphidicola and their allelopathic activity on Lactuca sativa (lettuce)

    Energy Technology Data Exchange (ETDEWEB)

    Rocha, D.; Takahashi, J.A.; Boaventura, M.A.D. [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Dept. de Quimica], e-mail: dianadb@netuno.lcc.ufmg.br

    2009-01-15

    The use of microorganisms to induce chemical modifications in organic molecules is a very useful tool in organic synthesis, to obtain biologically active substances. The fungus Cephalosporium aphidicola is known by its ability to hydroxylate several skeleton positions of many classes of organic compounds. In this work, the microbial transformation of ent-kaur-16-en-19-01 (1) by C. aphidicola, afforded two hydroxylated compounds, ent-kauran-16{beta},19-diol (2) and ent-kauran-16{beta},17,19-triol (3). Their structures were established by 1D and 2D-NMR studies. Both compounds were tested for their action on the growth of radical and shoot of Lactuca sativa. (author)

  8. The influence of the combined effects of acute gamma-radiation, sodium bromate and sodium nitrate on lettuce (Lactuca sativa) seedling root growth

    Energy Technology Data Exchange (ETDEWEB)

    Pryakhin, E.; Osipov, D. [Urals Research Center for Radiation Medicine - URCRM (Russian Federation)

    2014-07-01

    Among special industrial reservoirs used for the storage of liquid radioactive waste of Mayak PA, Russia, one of the most radioactively contaminated is the R-17 reservoir, so-called 'Staroye Boloto' (the total β-activity of water ranged in the observation period from 0.4 MBq/l to 4.5 MBq/l, the total a-activity ranged from 43 to 420 Bq/l). Also this reservoir is characterized by high level of chemical contamination, in particular, the concentration of nitrates in water is 2.5-4,4 g/l, sodium bromate - up to 35 mg/l. One of the interesting questions is interaction of radiation and chemical contamination in their effect on living organisms in this reservoir. In laboratory experiments seeds of Lactuca sativa were used; the effect of the studied factor on the length of the sprout's root was estimated. To assess the effect of chemical toxicants the solutions of each salt in 7 different concentrations were used, distilled water was used as a control. For evaluation of acute effects of external gamma irradiation the seeds after exposure for 24 hours in distilled water, were irradiated at 7 different doses using gamma-unit on the basis of Cs-137 with the dose rate of 0.62 Gy/min. To assess the combined effects of acute external gamma irradiation, of nitrates and bromates, seeds after 24 hour exposure at each test concentration of the salts solutions were irradiated using gamma-unit. To calculate the effective concentrations or doses was used drc package for R software. To calculate the dose rate to aquatic organisms in the R-17 was used ERICA Assessment Tool 2012. It was found out that the EC50 of sodium nitrate for lettuce was 2.69 g/l, which is comparable to the concentration of nitrates in the 'Staroye Boloto'. This indicates that nitrate can have significant toxic effect on aquatic higher plants of the reservoir. The EC50 of sodium bromate was 14.6 mg/l. This is less than the maximum concentration of the substance in the R-17, which suggests

  9. Benzoxazolin-2(3H)-one (BOA) induced changes in leaf water relations, photosynthesis and carbon isotope discrimination in Lactuca sativa.

    Science.gov (United States)

    Hussain, M Iftikhar; González, L; Chiapusio, G; Reigosa, M J

    2011-08-01

    The effects are reported here of Benzoxazolin-2(3H)-one (BOA), an allelopathic compound, on plant water relations, growth, components of chlorophyll fluorescence, and carbon isotope discrimination in lettuce (Lactuca sativa L.). Lettuce seedlings were grown in 1:1 Hoagland solution in perlite culture medium in environmentally controlled glasshouse. After 30 days, BOA was applied at concentration of 0.1, 0.5, 1.0 and 1.5 mM and distilled water (control). BOA, in the range (0.1-1.5 mM), decreased the shoot length, root length, leaf and root fresh weight. Within this concentration range, BOA significantly reduced relative water content while leaf osmotic potential remained unaltered. Stress response of lettuce was evaluated on the basis of six days of treatment with 1.5 mM BOA by analyzing several chlorophyll fluorescence parameters determined under dark-adapted and steady state conditions. There was no change in initial fluorescence (F₀) in response to BOA treatment while maximum chlorophyll fluorescence (F(m)) was significantly reduced. BOA treatment significantly reduced variable fluorescence (F(v)) on first, second, third, fourth, fifth and sixth day. Quantum efficiency of open PSII reaction centers (F(v)/F(m)) in the dark-adapted state was significantly reduced in response to BOA treatment. Quantum yield of photosystem II (ΦPSII) electron transport was significantly reduced because of decrease in the efficiency of excitation energy trapping of PSII reaction centers. Maximum fluorescence in light-adapted leaves (F'(m)) was significantly decreased but there was no change in initial fluorescence in light-adapted state (F'₀) in response to 1.5 mM BOA treatment. BOA application significantly reduced photochemical fluorescence quenching (qP) indicating that the balance between excitation rate and electron transfer rate has changed leading to a more reduced state of PSII reaction centers. Non photochemical quenching (NPQ) was also significantly reduced by BOA

  10. Control in vitro de Botrytis (Botrytis cinerea), Mildiu (Bremia lactucae) Y Esclerotinia (Sclerotinia sclerotiorum) en lechuga (Lactuca sativa), usando extractos de Cola de Caballo (Equisetum arvense), Ortiga (Urtica dioica L.), Ruda (Ruta graveolens) y Tomillo (Thymus vulgaris).

    OpenAIRE

    Tayupanta Rodríguez, Verónica Vanessa

    2013-01-01

    Se realizó el control biológico de Botrytis cinerea, Bremia lactucae y Sclerotinia sclerotiorum, con 4 extractos de plantas: Ruta graveolens, Thymus vulgaris, Urtica dioica, Equisetum arvense y Trichoderma harzianum como tratamiento adicional. Se realizaron ensayos en laboratorio dentro de cajas Petri, donde se inoculó el hongo obtenido previamente en cultivo puro, junto con los extractos de cada planta para evaluar el halo de inhibición y se realizó el conteo del número de UFC (Unidades f...

  11. STUDY OF CHRONIC TOXICITY OF THE GLYPHOSATE HERBICIDE ON SEEDS OF PARSLEY, LETTUCE AND CORIANDER / ESTUDO DA TOXICIDADE CRÔNICA DO HERBICIDA GLIFOSATO PARA AS SEMENTES DE SALSA, ALFACE E COENTRO

    Directory of Open Access Journals (Sweden)

    ANA PAULA DO NASCIMENTO

    2009-11-01

    Full Text Available O glifosato é um herbicida do grupo dos fosfonatos, ele é amplamente usado como herbicida. Embora mate quase todas as plantas pode ser usado para eliminar as ervas daninhas durante o crescimento das plantações que são resistentes ao glifosato. Nesta pesquisa objetivou-se verificar os efeitos toxicológicos do herbicida glifosato utilizando como organismo teste sementes de salsa (Petrosolium sativum, alface (Lactuca sativa e coentro (Coriandrum sativum. O ensaio toxicológico consistiu em utilizar papel toalha umedecido com a amostra de glifosato, e vinte sementes distribuídas uniformemente em vasilhames com tampas, deixados em local seco e arejado, sendo regadas uma vez ao dia durante 5 dias. Foi possível verificar o efeito tóxico do glifosato para sementes de salsa nas concentrações acima de 90 mg.L-1, para sementes de alface nas concentrações acima de 4 mg.L-1 e para sementes de coentro concentração acima de 12 mg.L-1. Desta forma foi possível concluir que as sementes em estudo apresentaram uma elevada sensibilidade com possibilidade de ser aplicadas em ensaios de toxicidade.

  12. Chemical composition of essential oils and in vitro antioxidant activity of fresh and dry leaves crude extracts of medicinal plant of Lactuca Sativa L. native to Sultanate of Oman.

    Science.gov (United States)

    Al Nomaani, Rahma Said Salim; Hossain, Mohammad Amzad; Weli, Afaf Mohammed; Al-Riyami, Qasim; Al-Sabahi, Jamal Nasser

    2013-05-01

    To isolate and analyse the chemical composition in the essential oils and free radical scavenging activity of different crude extracts from the fresh and dry leaves of vegetable plants of Lactuca sativa L. (L. sativa). The essential oils and volatile chemical constituents were isolated from the fresh and dry leaves of L. sativa (lettuce) grown in Sultanate of Oman by hydro distillation method. The antioxidant activity of the crude extracts was carried out by well established free radical scavenging activity (DPPH) method. About 20 chemical compounds of different concentration representing 83.07% and 79.88% respectively were isolated and identified by gas chromatography-mass spectroscopy in the essential oils isolated from the fresh and dry leaves as α-pinene (5.11% and 4.05%), γ-cymene (2.07% and 1.92%), thymol (11.55% and 10.73%), durenol (52.00% and 49.79%), α-terpinene (1.66% and 1.34%), thymol acetate (0.99% and 0.67%), caryophyllene (2.11% and 1.98%), spathulenol (3.09% and 2.98%), camphene (4.11% and 3.65%), limonene (1.28% and 1.11%) representing these major chemical compounds. However, some other minor chemical constituents were also isolated and identified from the essential oil of lettuce including β-pinene, α-terpinolene, linalool, 4-terpineol, α-terpineol, o-methylthymol, L-alloaromadendrene and viridiflorene. The chemical constituents in the essential oils from the locally grown lettuce were identified in the following classes or groups of chemical compounds such as monoterpenes, sesquiterpenes volatile organic compounds and their oxygenated hydrocarbons. Therefore, the essential oils and the crude extracts from Omani vegetable species of lettuce are active candidates which would be used as antioxidant, antifungal or antimicrobial agents in new drugs preparation for therapy of infectious diseases.

  13. Produção de mudas de alface em bandejas e substratos comerciais Production of lettuce seedlings in different trays and commercial substrates

    Directory of Open Access Journals (Sweden)

    Paulo E. Trani

    2004-06-01

    Full Text Available Avaliou-se o desenvolvimento de mudas de alface (Lactuca sativa L. cv Vera produzidas em diferentes bandejas de poliestireno e em quatro substratos comerciais em um experimento em Campinas (SP, sob cultivo protegido, de 15/01 a 13/02/03. Os tratamentos consistiram na combinação fatorial de tipos de substratos (Plantmax HA, Hortimix folhosas, Golden Mix 47 e Vida Verde Tropstrato hortaliças e tamanhos de células em bandejas de poliestireno (200 e 288 células. O experimento foi disposto inteiramente ao acaso, com as parcelas subdivididas para época de avaliação, com três repetições sendo cada uma constituída de uma bandeja. As avaliações foram realizadas aos cinco, dez, quinze e vinte dias após a germinação sendo retiradas em cada uma, ao acaso, vinte plantas de cada bandeja. Foram avaliados suas alturas, número de folhas, estabilidade do torrão e a área foliar. O substrato Plantmax proporcionou aos 15 e 20 dias após a germinação, mudas de alface mais desenvolvidas em relação aos outros substratos. Independente do tipo de substrato, as bandejas de 200 células mostraram-se melhores que as de 288 células quanto ao número de folhas e área foliar por ocasião do transplante (20 dias.The effect of four commercial substrates in polystyrene trays with 200 and 288 cells, was evaluated on the production of seedlings of lettuce (Lactuca sativa cv. Vera in a plastic greenhouse, from 15/01 to 13/02/03, in Campinas, São Paulo State, Brazil. The treatments consisted of factorial combinations of four commercial substrates (Plantmax HA, Hortimix folhosas, Golden Mix 47 and, Vida Verde Tropstrato hortaliças and two cell sizes (200 and 288 cells. The experimental design was a randomized complete design, with the plots split with each part subdivided for the evalution time, with three repetitions, each beign made up of a tray. At 5; 10; 15 and 20 days after germination, twenty random plants from each plot were evaluated for their stem

  14. Atividade alelopática de extratos de diferentes orgãos de Caesalpinia ferrea na germinação de alface Allelopathic activity of extracts from different organs of Caesalpinia ferrea on lettuce germination

    Directory of Open Access Journals (Sweden)

    Andreya Kaliana de Oliveira

    2012-08-01

    Full Text Available A alelopatia pode afetar muitos aspectos da ecologia das plantas, incluindo a ocorrência, crescimento, sucessão de plantas, estrutura das comunidades, dominância, diversidade e produtividade. Neste trabalho, o objetivo foi avaliar o potencial alelopático de diversos órgãos de jucá (Caesalpinea ferrea sobre a germinação de sementes e desenvolvimento de plântulas de alface (Lactuca sativa. Foi usado o delineamento experimental inteiramente casualizado no esquema fatorial 2x5, com dois métodos de extração (25 e 100°C e cinco concentrações do extrato bruto (0, 25, 50, 75 e 100% para cada órgão avaliado: folhas, cascas e vagens maduras de C. ferrea, em quatro repetições de 25 sementes da alface 'Mônica SF FI'. As características avaliadas foram porcentagem de germinação (PG, índice de velocidade de germinação (IVG, porcentagem de plântulas normais (PN e anormais (PA, comprimentos da parte aérea (CPA e da raiz (CR de plântulas de alface. Os extratos de folhas e de vagens de C. ferrea obtidos a quente (100°C reduziram a porcentagem de germinação de L. sativa em relação à testemunha (0%. Nas maiores concentrações dos extratos de todos os órgãos, houve alta PA (atrofiamento da raiz, queima e escurecimento da radícula, encurvamento do caulículo, geotropismo negativo e menor CPA e CR, comparado à testemunha. Os extratos dos diferentes órgãos de C. ferrea apresentam atividade alelopática inibindo o desenvolvimento de plântulas de alface.Allelopathy can affect many aspects of plant ecology, including the occurrence, growth, plant succession, community structure, dominance, diversity and productivity of plants. The aim of this study was to evaluate the allelopathic potential of various organs of jucá (Caesalpinea ferrea on seed germination and seedling development of lettuce (Lactuca sativa. It was used in a completely randomized 2x5 factorial arrangement, with two extraction methods (25 and 100°C and

  15. Toxicity assessment using Lactuca sativa L. bioassay of the metal(loid)s As, Cu, Mn, Pb and Zn in soluble-in-water saturated soil extracts from an abandoned mining site

    Energy Technology Data Exchange (ETDEWEB)

    Bagur-Gonzalez, Maria Gracia [Univ. of Granada, Faculty of Sciences, Dept. of Analytical Chemistry, Granada (Spain); Univ. of Granada-CSIC, Inst. Andaluz de Ciencias de la Tierra, Faculty of Sciences, Granada (Spain); Estepa-Molina, Carmen [Univ. of Granada, Faculty of Sciences, Dept. of Mineralogy and Petrology, Granada (Spain); Martin-Peinado, Francisco [Univ. of Granada, Faculty of Sciences, Dept. of Soil Science, Granada (Spain); Morales-Ruano, Salvador [Univ. of Granada-CSIC, Inst. Andaluz de Ciencias de la Tierra, Faculty of Sciences, Granada (Spain); Univ. of Granada, Faculty of Sciences, Dept. of Mineralogy and Petrology, Granada (Spain)

    2011-02-15

    We used the different soluble-in-water concentrations of As, Cu, Mn, Pb and Zn from contaminated soils in an abandoned mining area (anthropogenic origin) to assess the phytotoxicity of the abandoned site using the results obtained with a Lactuca sativa L. bioassay. Material and methods The study has been carried out on potentially polluted samples from the Rodalquilar mining district (southern Spain). The area was sampled according to the different metallurgical treatments for gold extraction used in each one: dynamic cyanidation and heap leaching. The saturation extracts were obtained by filtering each saturated paste with a vacuum-extraction pump, in which measurements of metal(loid) concentrations, pH and electrical conductivity were made. The variables evaluated in the bioassay, defined as toxicity indices ranging from -1 (maximum phytotoxicity) to >0 (hormesis), were seed germination (SG) and root elongation (RE) of lettuce seeds. Results and discussion In areas with a low degree of contamination, the most sensitive toxicity index is RE, whereas in highly contaminated areas, both RE and SG are good estimators of soil toxicity. According to these results, samples from the western area showed moderate to low toxicity, which was closely related to water-soluble As concentrations. Samples from the eastern area had a high degree of toxicity in 40% of the soils. Conclusions The comparison of the two indices (SG and RE) defined using the L. sativa L. bioassay indicates that, for areas with a low degree of contamination, the most sensitive toxicity index is RE, whereas in highly contaminated areas, both RE and SG are good estimators of soil phytotoxicity. Unsupervised pattern recognition methods such as HCA and PCA enabled us to conclude that the low/moderate phytotoxicity of the soils is related to the extraction process used for the recovery of gold (mainly dynamic cyanidation in tanks located in the eastern area) and to the As and Pb contents. (orig.)

  16. Exposure studies of core-shell Fe/Fe(3)O(4) and Cu/CuO NPs to lettuce (Lactuca sativa) plants: Are they a potential physiological and nutritional hazard?

    Science.gov (United States)

    Trujillo-Reyes, J; Majumdar, S; Botez, C E; Peralta-Videa, J R; Gardea-Torresdey, J L

    2014-02-28

    Iron and copper nanomaterials are widely used in environmental remediation and agriculture. However, their effects on physiological parameters and nutritional quality of terrestrial plants such as lettuce (Lactuca sativa) are still unknown. In this research, 18-day-old hydroponically grown lettuce seedlings were treated for 15 days with core-shell nanoscale materials (Fe/Fe(3)O(4), Cu/CuO) at 10 and 20mg/L, and FeSO(4)·7H(2)O and CuSO(4)·5H(2)O at 10mg/L. At harvest, Fe, Cu, micro and macronutrients were determined by ICP-OES. Also, we evaluated chlorophyll content, plant growth, and catalase (CAT) and ascorbate peroxidase (APX) activities. Our results showed that iron ions/NPs did not affect the physiological parameters with respect to water control. Conversely, Cu ions/NPs reduced water content, root length, and dry biomass of the lettuce plants. ICP-OES results showed that nano-Cu/CuO treatments produced significant accumulation of Cu in roots compared to the CuSO(4)·5H(2)O treatment. In roots, all Cu treatments increased CAT activity but decreased APX activity. In addition, relative to the control, nano-Cu/CuO altered the nutritional quality of lettuce, since the treated plants had significantly more Cu, Al and S but less Mn, P, Ca, and Mg. Copyright © 2013 Elsevier B.V. All rights reserved.

  17. Crescimento, consumo hídrico e composição mineral de alface cultivada em hidroponia com águas salinas

    Directory of Open Access Journals (Sweden)

    Dalva Paulus

    2012-02-01

    Full Text Available Objetivou-se, com este trabalho, avaliar o crescimento, o consumo hídrico e a extração de nutrientes, por alface (Lactuca sativa L. em sistema hidropônico NFT (fluxo laminar de nutrientes, com a utilização de águas salinas no preparo da solução nutritiva e reposição da lâmina diária evapotranspirada. Foram conduzidos dois experimentos, em ambiente protegido. O delineamento experimental foi em blocos ao acaso, sendo estudados os efeitos de cinco níveis de salinidade da água, utilizando-se NaCl. O aumento da salinidade da água reduziu, de forma linear, o crescimento e o consumo hídrico da alface. A salinidade reduziu a concentração de macronutrientes na parte aérea, mas não se observaram sintomas de deficiência nutricional. O rendimento (massa de matéria fresca da parte aérea foi reduzido entre 6 e 6,5% por dS m-1, no primeiro e segundo cultivo, respectivamente. Os resultados obtidos em sistema de cultivo NFT podem indicar a possibilidade do uso da água salina como alternativa para produção de hortaliças, para produtores que têm disponibilidade restrita de água doce, porém, com redução de produtividade.

  18. Efeito alelopático de Andira humilis Mart. ex Benth na germinação e no crescimento de Lactuca sativa L. e Raphanus sativus L. Allelopathic effect of Andira humilis Mart. ex Benth in the germination and growth of Lactuca sativa L. and Raphanus sativus L.

    Directory of Open Access Journals (Sweden)

    Fernando Periotto

    2004-09-01

    Full Text Available Neste trabalho, objetivou-se avaliar o efeito alelopático de caules e folhas de Andira humilis na germinação de sementes e no crescimento de plântulas de rabanete e alface. Para os experimentos de germinação foram preparados extratos aquosos de caules e folhas de A. humilis nas concentrações de 0, 4, 8, 12 e 16% (p/v. Foram realizadas quatro réplicas de trinta sementes de alface ou de rabanete, distribuídas em placas de Petri forradas com papel-filtro umedecido com 5mL dos extratos, mantidas a 27 ºC e na ausência de luz. As contagens das sementes germinadas foram realizadas a cada 12h, calculando-se a percentagem e a velocidade de germinação. Extratos de caules e folhas reduziram significativamente a velocidade e a percentagem de germinação, em relação ao grupo controle. Os experimentos de crescimento foram realizados com quatro réplicas de oito sementes germinadas de alface ou de rabanete, a 27 ºC, na ausência de luz e em papel-filtro como substrato, sendo avaliadas as concentrações 0, 4 e 12% (p/v. Plântulas de alface e rabanete sofreram inibição significativa em seus comprimentos, pelos extratos de folhas. Extratos de caules a 4 e 12% (p/v não causaram inibição do crescimento em rabanete. A interferência dos extratos na germinação e no crescimento em alface e rabanete foi desassociada de qualquer efeito do potencial osmótico e do pH, indicando, portanto, atividade alelopática.The objective of this study was to evaluate allelopathic effects of stems and leaves of Andira humilis in the germination and growth of radish and lettuce. For the germination's experiments, aqueous extracts of stems and leaves of A. humilis in the concentrations of 0, 4, 8, 12 e 16% (w/v were done. Were employed four replicates of thirty seeds of lettuce and radish. The seeds were distributed in Petri dishes with filter paper moistened with 5mL of the extracts. The experiments were conducted at 27 ºC in light absence. The counting of

  19. Variação sazonal na alelopatia de extratos aquosos de Coleus barbatus (A. Benth. sobre a germinação e o desenvolvimento de Lactuca sativa L. Seasonal variation in the allelopathy of aqueous extracts from Coleus barbatus (A. Benth. on the germination and development of Lactuca sativa L.

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    L.L. Pelegrini

    2012-01-01

    Full Text Available O objetivo deste trabalho foi avaliar o efeito alelopático de extratos de Coleus barbatus sobre a germinação e desenvolvimento de plântulas de alface. Os experimentos foram conduzidos em laboratório, em diferentes concentrações de extratos obtidos de folhas de falso-boldo (0; 7,5; 15; 22,5; 30%, coletadas nas quatro estações do ano, obtidos por trituração, maceração, infusão e decocção. As sementes de alface foram distribuídas sobre placas de petri umidecidas com 10 mL de solução. Os resultados mostraram que os extratos de folhas afetaram a germinabilidade de sementes de alface apenas na concentração de 30% do extrato preparado por decocção de folhas coletadas no inverno. O índice de velocidade de germinação apresentou redução significativa nos extratos triturados preparados no outono e inverno; na maceração de folhas coletadas no verão e outono e no extrato de decocção preparado no inverno. Os extratos estimularam o crescimento da parte aérea das plântulas de alface, ao passo que, o comprimento das raízes foi afetado pelos extratos, ora inibindo, ora estimulando o crescimento das mesmas. Os extratos de folhas de falso-boldo coletadas nas quatro estações do ano apresentaram efeito alelopático sobre a germinação e o desenvolvimento da alface, sendo que estes variaram em função da sazonalidade da coleta, da forma de obtenção dos extratos e das concentrações testadas.The aim of this study was to evaluate the allelopathic effects of extracts from Coleus barbatus on germination and seedling growth of lettuce. The experiments were conducted in the laboratory using different concentrations (0, 7.5, 15, 22.5, 30% of aqueous extracts from "falso-boldo" leaves harvested in all four seasons; extracts were obtained by grinding, maceration, infusion and decoction. Seeds were distributed on Petri dishes moistened with 10 mL solution. Results showed that the leaf extracts affected the germination of lettuce seeds

  20. Efeito de extratos orgânicos, associados ao surfactante tween 80, na germinação e crescimento de plântulas de alface Effect of organic extracts associated with surfactant Tween 80 on seed germination and seedling growth of lettuce

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    Cláudio Costa dos Santos

    2004-04-01

    Full Text Available Com este trabalho, visou-se a identificar, por meio de bioensaio, o efeito dos extratos de caruru (Amaranthus retroflexus L., capim-marmelada (Brachiaria plantaginea (Link. Hitchc., mentrasto (Ageratum conyzoides L. e de três cultivares de milho (AG1051, C333 e C435 sobre a germinação e crescimento de alface (Lactuca sativa L. cv. Marisa AG216. Os extratos metanólicos foram concentrados sob vácuo e solubilizados em surfactante Tween 80 a 1% (v/v em água. A seguir, aplicaram-se as soluções obtidas em papel de filtro sobre placa de Petri, onde foi semeada alface. Utilizaram-se água destilada como testemunha e surfactante Tween 80 a 1% como tratamento branco. O extrato de mentrasto, o de caruru e da cultivar de milho AG1051 promoveram redução no índice de velocidade de germinação em relação à testemunha com água destilada. O percentual de germinação foi afetado apenas pelo extrato de mentrasto (82,5% de redução. Todos os extratos e o surfactante Tween 80 provocaram inibição do crescimento de radículas de plântulas de alface, com redução de comprimento de raiz entre 9,53 e 14,83 mm, e de hipocótilo, entre 21,6 a 30,95 mm.This work aimed at identifying, through bioassay, the effect of organic extracts of pigweed (Amaranthus retroflexus L., signal grass (Brachiaria plantaginea (Link. Hitchc., ageratum (Ageratum conyzoides L. and three corn cultivars (AG1051, C333 and C435 on lettuce (Lactuca sativa L. cv. Marisa AG216 germination and seedling. Thus, the methanolic extracts of their straws were concentrated under vacuum and dissolved in 1% (v/v aqueous surfactant Tween 80. Then, the resulting solutions were applied to filter papers contained in Petri dishes, where lettuce was sowed. Distilled water and 1% Tween 80 were used as controls treatment. The corn cultivar extracts AG1051, pigweed and ageratum promoted reduction of the germination index in relation to the control with distilled water. The germination percentage was

  1. Anita: cultivar de alface de verão para cultivo protegido no solo e em hidroponia 'Anita': a new summer lettuce cultivar suitable for protected cultivation in soil and hydroponics systems

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    Ernani Clarete da Silva

    2009-06-01

    Full Text Available 'Anita' é uma cultivar de alface (Lactuca sativa L. do grupo lisa, de cor verde-clara intensa, cujo desenvolvimento se deu a partir de 1994 no município de Campos dos Goytacazes, RJ. Foi selecionada pelo método genealógico a partir do cruzamento entre as cultivares comerciais Vitória e Brasil 303. As plantas contêm diâmetro médio de cabeça de 55 cm, massa fresca de 700 g e número médio de 55 folhas, conforme resultados de ensaios conduzidos nas quatro estações do ano. Possui resistência ao LMV e ao pendoamento precoce em cultivos de verão. As folhas são grandes, macias, crocrantes e adocicadas, sendo estas características mantidas tanto no cultivo protegido no solo quanto em hidroponia.'Anita' is a lettuce cultivar (Lactuca sativa L. of the loose-leaf group whose leaves are of intense green color. This cv. was developed in Campos dos Goytacazes, Rio de Janeiro State, Brazil, since 1994. "Anita" was selected by the pedigree method through crossings between commercial cultivars Vitória and Brasil 303. After evaluations done during four seasons, there were detected a head mean diameter around 55 cm, average fresh plant weight of 700 g and 55 leaves in average. Plants present resistance to Lettuce Mosaic Virus (LMV and high resistance to bolting in the summer. In both cultivation systems, protected environment or hydroponics, plants present leaves of great size, soft and sweet.

  2. Reversed-phase ultra-high-performance liquid chromatography coupled to electrospray ionization-quadrupole-time-of-flight mass spectrometry as a powerful tool for metabolic profiling of vegetables: Lactuca sativa as an example of its application.

    Science.gov (United States)

    Abu-Reidah, I M; Contreras, M M; Arráez-Román, D; Segura-Carretero, A; Fernández-Gutiérrez, A

    2013-10-25

    Lettuce (Lactuca sativa), a leafy vegetal widely consumed worldwide, fresh cut or minimally processed, constitutes a major dietary source of natural antioxidants and bioactive compounds. In this study, reversed-phase ultra-high-performance liquid chromatography (RP-UHPLC) coupled to electrospray ionization-quadrupole-time-of-flight mass spectrometry (ESI-QTOF-MS) was applied for the comprehensive profiling of polar and semi-polar metabolites from three lettuce cultivars (baby, romaine, and iceberg). The UHPLC systems allowed the use of a small-particle-size C18 column (1.8 μm), with very fine resolution for the separation of up to seven isomers, and the QTOF mass analyzer enabled sensitive detection with high mass resolution and accuracy in full scan. Thus, a total of 171 compounds were tentatively identified by matching their accurate mass signals and suggested molecular formula with those previously reported in family Asteraceae. Afterwards, their structures were also corroborated by the MS/MS data provided by the QTOF analyzer. Well-known amino acids, organic acids, sesquiterpene lactones, phenolic acids and flavonoids were characterized, e.g. lactucin, lactucopicrin, caftaric acid, chlorogenic acid, caffeoylmalic acid, chicoric acid, isochlorogenic acid A, luteolin, and quercetin glycosides. For this plant species, this is the first available report of several isomeric forms of the latter polyphenols and other types of components such as nucleosides, peptides, and tryptophan-derived alkaloids. Remarkably, 10 novel structures formed by the conjugation of known amino acids and sesquiterpene lactones were also proposed. Thus, the methodology applied is a useful option to develop an exhaustive metabolic profiling of plants that helps to explain their potential biological activities and folk uses. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. AVALIAÇÃO MICROBIOLÓGICA DE ALFACES (LACUTA SATIVA L. CONVENCIONAIS E ORGÂNICAS E A EFICIÊNCIA DE DOIS PROCESSOS DE HIGIENIZAÇÃO

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    Evelin de Alencar COSTA

    2012-08-01

    Full Text Available O processo de higienização das hortaliças cruas deve garantir a segurança do consumo das mesmas. De acordo com a legislação, esse procedimento deve compreender uma lavagem apenas em água corrente e em seguida desinfecção por meio de imersão em solução clorada a 200 ppm por no mínimo 15 minutos. No entanto, poucas pesquisas são realizadas a fim de conhecer a eficácia do uso de sanitizantes específicos para vegetais. Diante disso, o presente trabalho teve por objetivo avaliar nas alfaces provenientes de cultivos convencional e orgânico, comercializadas em Fortaleza-CE, dois processos de higienização: o tradicional (utilizando apenas solução clorada a 200 ppm de hipoclorito de cálcio e o método teste proposto, utilizando o detergente específico para vegetais Nitrol WV2640 (a base de óleo de coco e soja, seguido de solução clorada a 200 ppm de hipoclorito de cálcio e determinações de coliformes a 45°C ou termotolerantes e Salmolella sp. Em cada etapa dos processos de higienização foram coletadas amostras para análise de coliformes termotolerantes e Salmonella sp, conforme APHA (2001. As amostras convencionais apresentaram contaminação maior de coliformes a 45°C do que as orgânicas, respectivamente, 346 NMP/g e 57 NMP/g. A pré-lavagem mostrou eficácia na redução de aproximadamente 50% da contaminação de coliformes a 45°C em ambas as alfaces. As amostras convencionais e orgânicas lavadas com detergente tiveram redução signi- ficativa na contagem de coliformes de aproximadamente 50%. Alfaces in naturas de sistemas de cultivos convencionais se apresentaram, antes da lavagem ou higienização, em desconformidade com a legislação do Brasil para coliformes a 45°C. Alfaces in naturas de sistemas de cultivos orgânicos e convencional se apresentaram, após lavagens com detergente ou higienizadas, em conformidade com a legislação do Brasil para coliformes a 45°C. O uso do detergente Nitrol WV2640

  4. Eficiência de soluções antimicrobiana na desinfecção de alface tipo crespa comercializada em feira livre

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    Inácia dos Santos Moreira

    2013-09-01

    Full Text Available O consumo de hortaliças cruas constitui um importante veiculo de transmissão de doenças de origem alimentar (DTA. Essa contaminação pode ocorrer antes e após a colheita, através do contato com o solo, irrigação com água contaminada, transporte e pelas mãos dos manipuladores. A alface (Lactuca sativa é a hortaliça folhosa mais comercializada no Brasil.  O objetivo deste trabalho foi verificar a eficiência de sanificantes a base de cloro e vinagre na desinfecção de amostras de alfaces. As amostras foram coletadas no mercado Pirajá da cidade de Juazeiro do Norte - CE e transportado até os laboratórios: Processamento vegetal para sanitização, físico-químico para realização da análise de acidez titulável e microbiologia de alimentos, onde foram realizadas análises de coliformes a 35ºC e a 45ºC, Staphylococcus aureus e Salmonella spp, segundo as normas da APHA (American Public Health Association. O resultado das análises de acidez da alface higienizada com água, água + vinagre e água + hipoclorito foram em média: 0,1% para todas as amostras. Os resultados obtidos para coliformes 35ºC e a 45ºC mostraram que apenas a amostra que foi lavada apenas com água estava fora dos padrões estabelecidos pela legislação, para Staphylococcus aureus e Salmonella spp revelaram que todas as amostras (100% encontravam-se de acordo com o padrão federal vigente. Palavras - Chaves: contaminação microbiológica, sanitizantes, higiene alimentar. 

  5. Особливості формування колекції сортів салату посівного (Lactuca sativa L.) з еталонними ознаками

    OpenAIRE

    Лещук, Н. В.

    2014-01-01

    Peculiarities of the formation of the collection of lettuce (Lactuca sativa L.) varieties with reference characteristics are considered. Methodological requirements for the formation, grouping, maintenance, use and updating of the examples varieties collection for identifi cation of all lettuce varieties were scientifi cally grounded. Varieties with relevant morphological characteristics and notes of their expressions for vegetative and generative organs of lettuce plants were identifi ed. Th...

  6. Produção de mudas de alface em função de diferentes combinações de substratos Production of lettuce seedlings for different combinations of substrata

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    Gilson Araújo de Freitas

    2013-03-01

    Full Text Available O substrato utilizado na produção de mudas exerce papel primordial, no desenvolvimento inicial da planta. Neste sentido, com o presente trabalho objetivou-se avaliar a produção de mudas de alface em função de diferentes combinações de substratos. O experimento foi implantado seguindo um delineamento inteiramente casualizado, com quatro repetições. Os 20 tratamentos foram dispostos em esquema fatorial 4x5; sendo o primeiro fator constituído por quatro substratos (PlantHort I, PlantHort II, PlantHort III e substrato comercial Plantmax® e o segundo constituído de cinco níveis de casca de arroz carbonizada (0; 25; 50; 75; 100%. Foi utilizada a cultivar de alface Elba (Lactuca sativa L.. As sementes foram semeadas nos diferentes substratos contidos em bandejas de poliestireno expandido, com 128 células, na profundidade 0,5 cm. O aumento da porcentagem de casca de arroz carbonizada nos substratos avaliados apresentou comportamentos semelhantes em todas as características avaliadas. Os substratos PlantHort I, PlantHort II, PlantHort III considerados alternativos, independentemente da proporção adicionada de casca de arroz carbonizada proporcionaram maiores crescimentos em relação ao substrato comercial Plantmax®.The substratum used in seedling production has a key role in the initial development of the plant. To this effect, the present work aimed to evaluate the production of lettuce seedlings for different combinations of substrata. The experiment was set up following a completely randomized design with four replications. The 20 treatments were arranged in a 4x5 factorial, the first factor consisting of four substrata (PlantHort I, PlantHort II, PlantHort III and the commercial substratum Plantmax® and the second consisting of five levels of burnt rice husks (0, 25, 50 , 75, 100%. The lettuce cultivar used was Elba (Lactuca sativa L.. The seeds were sown in the different substrates contained in polystyrene trays of 128 cells, at

  7. Seedling formation and field production of beetroot and lettuce in Aquidauana, Mato Grosso do Sul, Brazil Formação de mudas e produção a campo de beterraba e alface em Aquidauana-MS

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    Paulo AM Leal

    2011-12-01

    Full Text Available In horticulture, the proper use of containers and substrates for the production of seedlings are important factors that affect crop productivity in the field. This study aimed to evaluate the effect of different containers and substrates in the production of lettuce (Lactuca sativa, cv Veneranda and beetroot (Beta vulgaris, cv Top Tall Early Wonder seedlings in nursery with monofilament screen, 50% of shading, and the productivity of these species when transplanted to field plots. In protected cultivation, a completely randomized experimental design, in a 3 x 3 factorial scheme (three polystyrene trays, R1= 72, R2= 128 and R3= 200 cells and three substrates, S1= 93% of soil + 7% of organic compost, S2= 86% of soil + 14% of organic compost and S3= 79% of soil + 21% of organic compost was used, with 15 replications, where one plantlet was a replication. In the field, the nine treatments were evaluated in a completely randomized experimental design. The 72 cells tray with 7% commercial organic compost substrate promoted the best beetroot and lettuce seedlings. In the field, the plants from the 72 cell tray produced greater plants, independent of substrates type.Na olericultura o uso adequado de recipientes e substratos para a produção de mudas são fatores importantes e que afetam a produtividade das culturas a campo. No presente trabalho objetivou-se avaliar, em viveiro de tela de monofilamento com 50% de sombreamento, o efeito de diferentes recipientes e substratos na produção de mudas de alface (Lactuca sativa, cv Veneranda e beterraba (Beta vulgaris, cv Top Tall Early Wonder, bem como a produtividade dessas espécies quando transplantadas em canteiros a campo. No ambiente protegido utilizou-se o delineamento experimental inteiramente casualizado, em esquema fatorial 3 x 3, sendo os fatores 3 recipientes (R1= 72, R2= 128 e R3= 200 células de poliestireno e 3 substratos (S1= 93% de solo + 7% de composto orgânico, S2= 86% de solo + 14% de

  8. Atividade alelopática de folhas e pseudofrutos de Hovenia dulcis Thunb. (Rhamnaceae sobre a germinação de Lactuca sativa L. (Asteraceae Allelopathic activity of Hovenia dulcis Thunb. (Rhamnaceae leaves and pseudofruits on the germination of Lactuca sativa L. (Asteraceae

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    Alana Cristina Dorneles Wandscheer

    2011-03-01

    Full Text Available Neste trabalho, objetivou-se avaliar o efeito alelopático de folhas secas e pseudofrutos de Hovenia dulcis Thunb. sobre sementes de alface. Para isso, prepararam-se extratos aquosos de folhas e pseudofrutos nas concentrações 1, 2 e 4% (m/v. Realizou-se quatro repetições de 25 sementes de alface, distribuídas em placas de Petri forradas com papel Germitest e umedecidas com os extratos, mantidas em câmara de germinação à temperatura de 25°C, fotoperíodo constante e presença de luz por cinco dias, sendo o controle água destilada. Calculou-se a porcentagem, a velocidade, o índice de velocidade de germinação, o comprimento radicular e da parte aérea das plântulas, bem como o efeito das sementes na presença de diferentes soluções de pH. Observou-se que as plântulas foram significativamente afetadas na presença de extratos aquosos de folhas secas e pseudofrutos nas concentrações 2 e 4%. Os efeitos foram desvinculados do pH e potencial osmótico, indicando, portanto, interferência alelopática dos extratos obtidos de Hovenia dulcis.This paper aims to evaluate the allelopathic effect of dry leaves and pseudofruits of Hovenia dulcis Thunb. on lettuce seeds. Therefore, aqueous extracts of leaves and pseudofruits were prepared in 1%, 2% and 4% (m/v concentrations. Four replicates were done of 25 lettuce seeds distributed in Petri dishes lined with Germitest paper and humidified with the extracts, maintained in germination chamber at 25 °C, constant photoperiod and light presence for five days, the control being distilled water. The percentage, speed, germination rate index, root length and aerial-part length of the seedlings were calculated, as well as the seeds effect in the presence of different pH solutions. It was observed that the seedlings were significantly affected in the presence of aqueous extracts of dry leaves and pseudofruits at 2% and 4% concentrations. The effects were not linked to pH and osmotic potential

  9. AVALIAÇÃO PARASITOLÓGICA EM LACTUCA SATIVA (ALFACE E BRASSICA OLERACEA L. (COUVE PROCEDENTES DA CEASA NO MUNICÍPIO DE ANÁPOLIS – GO

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    Léa Resende Moura

    2016-06-01

    Full Text Available Objective: To investigate the occurrence of intestinal parasites of interest to health in vegetables sold in Central de Abastecimento de Goiás S.A (CEASA in the city of Anapolis (GO. Methods: 42 samples of lettuce and cabbage were collected during the second half of January 2012 and submitted to the spontaneous sedimentation technique. Results: There were 11.9% and 14.2% of samples of lettuce and cabbage contaminated respectively. Conclusions: The most prevalent enteroparasites were Endolimax nana (lettuce: 19% and cabbage: 14.2%, Entamoeba coli (lettuce: 0 % and cabbage: 9.2% and Ascaris lumbricoides (lettuce: 4.7% and cabbage: 0 %. Possibly the lack of supervision for observance of compliance with standards for implementation of marketing within the CEASAAnapolis (GO promotes non-compliance with such rules and compromises the quality of products.

  10. Atividade alelopática da fração metanólica da folha de Lafoensia pacari A. ST.-HIL. na germinação e crescimento do alface

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    R. S. P. Malheiros

    2014-11-01

    Full Text Available A alelopatia é um processo envolvendo substâncias químicas produzidas por plantas que, uma vez liberadas no ambiente, influenciam o crescimento e desenvolvimento de outras plantas nas proximidades. Nesse contexto, a alelopatia tem sido proposta como uma possível alternativa para o manejo de plantas daninhas. Lafoensia pacari é uma espécie vegetal bastante utilizada para fins medicinais. Essas características farmacológicas são consequências da presença de flavonoides, presentes principalmente na folha. Numerosos flavonoides e seus glicosídeos são conhecidos na literatura por inibir o crescimento de outras plantas. Assim, objetivou-se investigar o efeito alelopático da fração metanólica foliar de pacari no desenvolvimento inicial de alface (Lactuca sativa. Nos bioensaios foram utilizadas as concentrações: 250, 500 e 1000mg/L, além do controle. O delineamento experimental foi inteiramente casualizado, com quatro repetições, constituídas de 25 sementes para os bioensaios de germinação e 10 plântulas para os bioensaios de crescimento. A fração metanólica não promoveu efeito na germinação e no crescimento do hipocótilo de alface, porém as concentrações de 250 e 500mg/L inibiram o crescimento da radícula em 26%, e a concentração de 1000mg/L proporcionou uma inibição de 43%. Conclui-se que L. pacari possui metabólitos que tornam a espécie viável para novos estudos para obtenção de herbicidas naturais.

  11. Efeitos de tipos de bandejas e idade de transplantio de mudas sobre o desenvolvimento e produtividade da alface americana

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    Resende Geraldo M. de

    2003-01-01

    Full Text Available Avaliou-se a influência de tipos de bandeja e idade de transplantio das mudas de alface (Lactuca sativa L. tipo americana em ensaio, realizado de março a junho de 2002 no município de Três Pontas, MG. Utilizou-se o delineamento experimental em blocos ao acaso em esquema fatorial 3 x 5, compreendendo três tipos de bandejas (128; 200 e 288 células, cinco idades de transplantio (22; 26; 30; 34 e 38 dias após a semeadura e 3 repetições. Mudas produzidas em bandejas de poliestireno expandido com 128 células e transplantadas com 38 dias de idade apresentaram maior massa fresca e seca, número de folhas e altura de plantas. A maior produtividade comercial foi obtida com as mudas produzidas em bandejas de 128 células, seguida da bandeja com 200 células, sendo o pior desempenho apresentado pelas mudas produzidas em bandejas com 288 células. A idade de transplantio das mudas variou em função do tipo de bandeja utilizado, podendo as mudas serem transplantadas de 22-38 dias da semeadura quando são utilizadas as bandejas com 128 e 200 células, com preferência para os períodos menores (22-30 dias. Para a bandeja com 288 células, as mudas devem ser transplantadas mais tardiamente, aos 38 dias da semeadura.

  12. Determinación de enteroparásitos en lechuga Lactuca sativa en fincas dedicadas a su producción en Pasto, Nariño, Colombia

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    Giovanni Andrés Polo

    2016-12-01

    Full Text Available Introducción. Actualmente las verduras, como la lechuga, se recomiendan ampliamente como parte de la dieta diaria por su gran aporte nutricional, sin embargo, los consumidores al sentirse atraídos por los beneficios proporcionados por la hortaliza, están expuestos a infecciones con parásitos intestinales. Objetivo. Determinar la presencia o ausencia de enteroparásitos en la lechuga (Lactuca sativa cultivada en la zona rural de municipio de Pasto y analizar factores asociados previa caracterización de los predios. Materiales y métodos. Se realizó un estudio transversal doble ciego de tipo descriptivo. Se tomaron 105 muestras de 21 predios en el periodo de junio a diciembre de 2013 y se procesaron mediante pruebas de flotación y sedimentación. Adicionalmente, se encuestó a los propietarios para obtener información sobre las posibles variables que influyen en la aparición de enteroparásitos. Resultados. Se encontró contaminación del 100% de las muestras, las cuales presentaban estructuras parasitarias representadas en huevos y larvas correspondientes al 95,25% con quistes de Entamoeba spp., 71,43% con ooquistes de Isospora spp., 61,90% con larvas (L3 de Strongyloides stercoralis, 28,57% con huevos de Toxocara spp. y 4,76% con ooquistes de Eimeria spp. En los factores asociados mediante la prueba de Ji cuadrado, se encontró relación entre Entamoeba spp. con acequia (p= 0,008, perros (p= 0,008 y pozo séptico (p= 0,029 Isospora spp. con compostaje (p= 0,0001, perros (p= 0,0001 y babosas (p=0,002; Strongyloides stercoralis con manipulación (p= 0,003 y Toxocara spp. con el no uso de biodigestores (p= 0,002. Conclusiones. Existe contaminación de la lechuga por enteroparásitos en las áreas de cultivo del municipio de Pasto, los cuales provienen de fuentes animales y humanas como sus principales reservorios, y otros están presentes en el medio ambiente.

  13. Atividade alelopática de extratos aquosos de Aristolochia esperanzae O. Kuntze na germinação e no crescimento de Lactuca sativa L. e Raphanus sativus L. Allelopathic activity of aqueous extracts of Aristolochia esperanzae O. Kuntze in the germination and growth of Lactuca sativa L. and Raphanus sativus L.

    Directory of Open Access Journals (Sweden)

    Ana Beatriz Gatti

    2004-09-01

    Full Text Available O objetivo deste trabalho foi analisar os efeitos de extratos aquosos de diferentes órgãos de Aristolochia esperanzae na germinação e no crescimento de alface e rabanete. Todos os extratos preparados obedeceram à proporção de 100g de material vegetal fresco para 300mL de água destilada, que produziu o extrato considerado 100% concentrado. A partir deste, foram feitas diluições com água destilada para 75, 50 e 25%. Nos testes de germinação foram avaliados os efeitos dos extratos obtidos de folha, caule, raiz, fruto e flor a 100, 75, 50 e 25%. Para o teste de crescimento foram utilizados extratos de folha, caule e raiz na concentração de 100 e 50%. Nos testes de germinação foram utilizadas quatro repetições de 30 sementes distribuídas em placas de Petri forradas com duas folhas de papel de filtro umedecidas com 5 mL dos referidos extratos, secas durante 12h e reumedecidas com 4,5mL de água destilada. No primeiro teste avaliou-se a percentagem e a velocidade de germinação das sementes. No teste de crescimento, as sementes foram previamente germinadas (2-4mm de radícula e depois transferidas para caixas plásticas contendo os substratos de papel de filtro e fibra de coco umedecidos com os respectivos extratos. Avaliou-se a altura da parte aérea, o comprimento radicular, a massa seca das plântulas e a presença de anormalidades nas plântulas. Os testes foram mantidos à temperatura constante de 27ºC. Através dos resultados obtidos pode-se concluir que os extratos de folha foram os que mais afetaram a percentagem de germinação e que todos os extratos e as diferentes concentrações retardaram a germinação de sementes de alface e de rabanete. Quanto ao teste de crescimento, pode-se verificar que os extratos de caule e de raiz causaram anormalidades nas plântulas. As plântulas crescidas no substrato papel de filtro apresentaram maior inibição do crescimento, em relação àquelas crescidas no substrato fibra de coco

  14. The International Lactuca database

    NARCIS (Netherlands)

    Treuren, van R.; Menting, F.B.J.

    2014-01-01

    The International Lactuca Database includes accessions of species belonging to the genus Lactuca, but also a few accessions belonging to related genera. Passport data can be searched on-line or downloaded. Characterization and evaluation data can be accessed via the downloading section. Requests for

  15. Produção da alface em função do uso de diferentes fontes de fósforo em solo de Cerrado Lettuce yield under different phosphorus sources use in the cerrado soil

    Directory of Open Access Journals (Sweden)

    Regina Maria Q. Lana

    2004-09-01

    Full Text Available A alface (Lactuca sativa L. é uma hortaliça bastante exigente em fósforo, sendo pouco tolerante à acidez do solo. O objetivo deste trabalho foi avaliar a resposta da cultura da alface a diferentes fontes de fertilizantes fosfatados solúveis e reativos de lenta solubilidade, na presença de calagem, visando aumento da produtividade. Utilizou-se o delineamento em blocos casualizados, com seis tratamentos (superfosfato simples, termofosfato magnesiano, superfosfato triplo, Fosmag, fosfato reativo de Arad e testemunha na ausência de fósforo, em quatro repetições, conduzido em um latossolo vermelho Distrófico. Na ausência de fósforo obtiveram-se menores produções e diâmetro de plantas, bem como todas as demais variáveis de crescimento, indicando elevada resposta de fósforo pela cultura da alface. Houve resposta significativa às diferentes fontes de fósforo, no que diz respeito à massa fresca e seca da parte aérea, massa fresca de raízes e teor de P no solo, em ordem decrescente com as fontes Fosmag, superfosfato triplo, superfosfato simples, termofosfato magnesiano e fosfato reativo de Arad. Com relação à massa seca de raízes e diâmetro das plantas, as fontes Fosmag e superfosfato triplo foram equivalentes. Os teores de P acumulados nas folhas foram superiores para as fontes Fosmag, superfosfato triplo e superfosfato simples, quando comparados com o termofosfato magnesiano e Arad, em condições em que a acidez foi corrigida.The lettuce (Lactuca sativa L. is a very demanding crop for phosphorus, being little tolerant to the soil acidity. The response of the lettuce crop to sources of soluble and reactive phosphorus fertilizer of slow solubility was evaluated in the presence of liming. . The experimental design consisted of a randomizing complete block design with six treatments (single superphosphate, thermalphosphate magnesium, triple superphosphate, Fosmag, Arad phosphate rock and control without phosphorus, in four

  16. A Bayesian analysis of gene flow from crops to their wild relatives: cultivated (Lactuca sativa L.) and prickly lettuce (L. serriola L.) and the recent expansion of L. serriola in Europe

    NARCIS (Netherlands)

    Uwimana, B.; Andrea, D' L.; Felber, F.; Hooftman, D.A.P.; Nijs, den H.C.M.; Smulders, M.J.M.; Visser, R.G.F.; Wiel, van de C.C.M.

    2012-01-01

    Interspecific gene flow can lead to the formation of hybrid populations that have a competitive advantage over the parental populations, even for hybrids from a cross between crops and wild relatives. Wild prickly lettuce (Lactuca serriola) has recently expanded in Europe and hybridization with the

  17. Guaianolides from Lactuca saligna.

    Science.gov (United States)

    Khalil, A T; El-Fattah, H A; Mansour, E S

    1991-04-01

    The phytochemical investigation of the aerial parts of LACTUCA SALIGNA L. revealed the presence of lactucin, lactucopicrin, and a new guaianolide named 11beta,13-dihydrolactucopicrin. The structural configuration was established through spectral data.

  18. Relação entre coeficientes de cultura e graus-dia de desenvolvimento da alface Relationship between lettuce crop coeficient and growing degree days

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    Elio L. da Silva

    1999-07-01

    Full Text Available Este estudo foi conduzido na Fazenda Campbell da Universidade do Arizona , no período de junho de 1994 a fevereiro de 1995, com objetivo de determinar a equação do coeficiente de cultura (Kc como função de graus-dia de desenvolvimento (GDD usando a série de senos Fourier, para alface (Lactuca sativa, L., do tipo folhosa. Foram usadas dez parcelas casualizadas, irrigadas de maneira a manter o potencial matricial da água no solo acima ou igual a -20kPa, que constituiram as repetições na determinação dos valores de evapotranspiração máxima da cultura (ETm. Cada parcela foi constituida por seis canteiros de 1,0 m x 7,3 m, com duas linhas de plantas (cultivar Waldmann's Green em cada, com população, após desbaste, de 48 plantas por canteiro. A época de desbaste ocorreu com GDD de 228ºC e Kc médio de 0,4 e a colheita com GDD igual a 742ºC e Kc médio de 1,2. Os valores de Kc como função de GDD, em diferentes estádios do ciclo da cultura, permitiram gerar uma equação que pode ser inserida em programa de computador para manejo de irrigação, considerando um GDD final (GDD de ajuste de 900ºC.This research was carried out at the Campbell Farm of The University of Arizona, from June 1994 to February 1995, with the aim of determining a growing-degree-days-based crop coefficient (Kc equation for leaf lettuce (Lactuca sativa L., using the Fourier sine series model. Ten randomized experimental plots were irrigated, in order to maintain a soil matric potential greater or equal to -20 kPa, as replications for the determination of crop maximum evapotranspiration (ETm. Each plot consisted of six raised beds, 7.3 m long and 1.0 m wide, with two rows of lettuce (Lactuca sativa L., cv. Waldmann's Green thinned to a final population of 48 plants per bed. The thinning time occurred with a GDD of 228ºC and average Kc of 0.4. The harvest time occurred with GDD of 742ºC and average Kc of 1.2. The values of Kc as function of GDD, during the

  19. Monitoramento de raças de Bremia lactucae em 2010 e 2011 no Estado de São Paulo Monitoring of Bremia lactucae races in 2010 and 2011 in the state of São Paulo

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    Francine de Souza Galatti

    2012-12-01

    Full Text Available A alface é uma das mais importantes hortaliças folhosas cultivadas no Brasil. Porém, com a intensificação da produção, a dificuldade em se cultivar essa hortaliça tem aumentado principalmente pela infestação das áreas de produção pelo fitopatógeno Bremia lactucae Regel, agente causador do míldio, uma das principais doenças da alface. O objetivo deste trabalho foi identificar raças de Bremia lactucae nos anos de 2010 e 2011 nos principais municípios produtores de alface do Estado de São Paulo. Para isso, coletaram-se folhas com esporângios de B. lactucae em municípios produtores de alface, sendo que cada amostra foi considerada um isolado, totalizando 56 e 96 nos anos de 2010 e 2011, respectivamente. Os esporângios coletados foram multiplicados na cultivar suscetível Solaris, com posterior inoculação nas cultivares diferenciadoras, realizando-se as avaliações no mesmo dia do aparecimento da primeira esporulação na cultivar suscetível 'Green Tower' (DM 0. No ano de 2010, identificou-se um novo código de B. lactucae em alface (63/31/03/00, correspondente a uma nova raça na qual se propôs a denominação de SPBl:07. No ano de 2011, outros dois códigos de B. lactucae foram identificados (31/63/51/00 e 31/63/9/00, aos quais se propôs as denominações de SPBl:08 e SPBl:09, respectivamente.Lettuce is one of the most important leafy vegetables grown in Brazil. However, intensification of its production has led to increased difficulty in cultivating this vegetable, especially due to infestation of producing areas with the phytopathogen Bremia lactucae Regel, the causative agent of downy mildew, one of the worst diseases affecting lettuce. The aim of this study was to identify B. lactucae races in 2010 and 2011 in major lettuce producing cities in the state of Sao Paulo. Thus, leaves with sporangia of B. lactucae were collected from lettuce producing cities and each sample was considered an isolate, totaling 56 and 96 in

  20. Taro 'Chinês' em cultivo solteiro e consorciado com cenoura 'Brasília' e alface 'Quatro Estações' 'Chinês' taro in monocrop system and intercropped with 'Brasília' carrot and 'Quatro estações" lettuce

    Directory of Open Access Journals (Sweden)

    Néstor A Heredia Zárate

    2006-09-01

    Full Text Available Estudou-se a produtividade e a renda bruta do taro (Colocasia esculenta 'Chinês', da cenoura (Daucus carota 'Brasília' e da alface (Lactuca sativa 'Quatro estações' em cultivo solteiro e dos consórcios taro-cenoura e taro-alface, nas condições ambientais de Dourados-MS. Os cinco tratamentos foram arranjados, no campo, no delineamento experimental em blocos casualizados, com cinco repetições. Para cada espécie avaliaram-se diferentes componentes das plantas. O consórcio foi avaliado utilizando-se a expressão da razão de área equivalente (RAE e sua validação foi pela determinação da renda bruta. As maiores produções de alface foram de 1,57; 2,09 e 6,59 t ha-1 para massas de "cabeças" comerciais, não-comerciais e pendoadas, respectivamente, obtidas com o cultivo solteiro. As cenouras cultivadas solteiras foram 6,5 cm mais altas e produziram 6,83 t ha-1 a mais de massa fresca de raízes comerciais, em relação às consorciadas com o taro 'Chinês'. As maiores produções de folhas, rizomas-mãe e rizomas-filho comerciais do taro 'Chinês' foram obtidas no consórcio taro-alface e a de rizomas-filho não-comerciais foram no taro solteiro. As menores produções foram do consórcio taro-cenoura. As RAEs para os consórcios taro-cenoura e taro-alface foram de 1,06 e 1,83, respectivamente. Pela renda bruta, constatou-se que para os produtores de cenoura e de alface, os consórcios com o taro 'Chinês' poderiam ter induzido incrementos monetários por hectare de R$ 6.122,50 ou de R$ 20.045,00, respectivamente. Para o produtor de taro, somente o consórcio com a alface foi positivo, com aumento de R$ 7.313,50 ha-1.Yield and gross income of 'Chinês' taro (Colocasia esculenta, of 'Brasília' carrot (Daucus carota and of 'Quatro estações' lettuce (Lactuca sativa were evaluated in monocrop system and taro-carrot and taro-lettuce intercrops, in environmental conditions of Dourados, Mato Grosso do Sul State, Brazil. The five treatments

  1. Emprego de tipos de cobertura de canteiro no cultivo da alface Evaluation of mulch types on lettuce production

    Directory of Open Access Journals (Sweden)

    Valter C. de Andrade Júnior

    2005-12-01

    Full Text Available Com o objetivo de avaliar o efeito de diferentes coberturas de canteiro sobre as características agronômicas de cultivares de alface (Lactuca sativa L. tipo lisa, foi realizado um experimento na Universidade Vale do Rio Verde em Três Corações (MG. O delineamento experimental utilizado foi de blocos ao acaso em esquema fatorial 5 x 2, proveniente da combinação de cinco tipos de cobertura (plástico preto, capim braquiária seco, casca de arroz, casca de café e solo nu e duas cultivares de alface tipo lisa (Regina e Elisa, com 3 repetições. A colheita foi realizada 42 dias após o transplantio, sendo avaliados a produção total (t ha-1, produção comercial, massa média por planta, diâmetro médio de cabeça, diâmetro médio de caule, número médio de folhas e massa média de raiz. Foi observada interação significativa entre tipos de cobertura x cultivares somente para a característica massa média de raiz, tendo a cultivar Elisa apresentado maior massa média de raiz quando utilizadas as coberturas com casca de café e casca de arroz. A cobertura com casca de café foi a que proporcionou os melhores resultados, superando os demais tipos de cobertura para todas as características avaliadas. A cultivar Regina foi superior à Elisa em quase todas as características estudadas, exceto para diâmetro médio de caule onde não foi observada diferença significativa entre as cultivares. 'Elisa' também apresentou maior massa média de raiz que a cultivar Regina.An experiment was carried out at Universidade Vale do Rio Verde, Minas Gerais State, Brazil, to evaluate the effect of bed coverages on the agronomic characteristics of lettuce cultivars. The experimental design was of randomized complete blocks in a 5 x 2 factorial scheme with five types of mulch (black plastic; dry braquiaria grass; rice husk; coffee husk and nude soil, two leaf lettuce cultivars (Regina and Elisa and three replications. Plants were harvested 42 days after

  2. Irrigação no cultivo orgânico de alface utilizando Irrigás, tanque Classe A e um sistema automático de baixo custo

    Directory of Open Access Journals (Sweden)

    Fabíola Vieira Gonçalves

    2014-11-01

    Full Text Available O presente estudo teve como objetivo comparar um sistema automático de baixo custo a outras duas técnicas de manejo (sistema Irrigás e tanque classe A na cultura da alface (Lactuca sativa L. com relação à operacionalidade dos sistemas, custo dos equipamentos, lâminas aplicadas e dados de produção da cultura. O cultivo foi desenvolvido num delineamento experimental de blocos ao acaso, com quatro tratamentos casualizados em seis blocos. Os tratamentos foram caracterizados pelo sistema Irrigás, tanque Classe A (TCA e pelo uso de um acionador automático de baixo custo para irrigação (AAI, em duas tensões de água no solo (9,0kPa e 12,0kPa. Foram avaliados dados de lâmina aplicada, eficiência no uso da água e as variáveis de produção, área foliar, massa fresca e seca da parte aérea, diâmetro e altura da cabeça. Não houve diferença significativa entre os tratamentos para nenhuma das variáveis de produção avaliadas(P>0,05 e as lâminas totais referentes aos diferentes métodos de manejo foram próximas à evapotranspiração de referência (ETo acumulada no período. A eficiência no uso da água nos tratamentos TCA, AAI/9kPa, Irrigás, AAI/12kPa foi, respectivamente, 241,4; 217,9; 205,5 e 267,1kg ha-1 mm-1, enquanto as produtividades foram respectivamente, 32,80; 28,86; 28,80 e 35,45Mg ha-1. Os resultados obtidos são próximos de valores reportados na literatura, permitindo concluir que as metodologias de manejo avaliadas foram eficientes para o cultivo de alface, e que, dessa forma, a escolha do método dependerá da disponibilidade de mão-de-obra e também do nível de treinamento do agricultor.

  3. Economic analysis of organic greenhouse lettuce production in Turkey Análise econômica da produção orgânica de alface em estufas na Turquia

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    Sait Engindeniz

    2006-06-01

    Full Text Available Health issues and environmental concerns have drawn the attention to organic agriculture aiming to protect the natural balance and to produce without damaging the environment. This study aims determining economic feasibility of organic greenhouse lettuce (Lactuca sativa L. in an on farm trial, to foster organic greenhouse vegetable production in the preservation area of Tahtali Dam, projected as the sole water resource of Izmir, Turkey's third largest. A 384 m² greenhouse, constructed of galvanized metal tubing anchored and covered with a polyethylene was analyzed to identify typical operation procedures, and to determine unitary construction and operation cost. Organic lettuces were produced during autumn season of 2001-2002, testing different organic fertilizer applications, including two rates of farmyard and poultry manure (30 and 50 t ha-1 with and without two organic fertilizers based on either bacteria or algae. Economical analysis was performed according to different organic fertilizer applications. Cost, yield, and price data were analyzed to determine the profitability of a typical operation. Net return obtained from organic lettuce growing ranged between us $ 0.376 and us $ 0.901 m-2, as a result of different fertilizer applications.Preocupações sanitárias e ambientais têm atraído a atenção para a prática da agricultura orgânica como meio de proteger o balanço ambiental e produzir sem danificar o ambiente. Este estudo objetiva determinar a viabilidade econômica da produção em estufa da alface (Latuca sativa L. em um ensaio de campo, a fim de incentivar a produção orgânica de vegetais na área de preservação do Reservatório Tahtali, projetado como o único recurso hídrico de Izmir, a terceira maior cidade da Turquia. Uma estufa de tubos galvanizados (384 m², ancorados e cobertos com polietileno, foi analisada para identificar procedimentos operacionais padronizados e determinar custos unitários de construção e

  4. Fertilizantes de leguminosas como fontes alternativas de nitrogênio para produção orgânica de alface Legume fertilizers as alternative sources of nitrogen for organic lettuce production

    Directory of Open Access Journals (Sweden)

    Maxwell Merçon Tezolin Barros Almeida

    2008-06-01

    Full Text Available O objetivo deste trabalho foi avaliar o potencial de dois fertilizantes de leguminosas - produtos derivados do corte, desidratação e moagem da biomassa aérea das leguminosas mucuna-cinza (Mucuna pruriens e gliricídia (Gliricidia sepium - como fontes alternativas de nitrogênio (N para a produção orgânica de alface (Lactuca sativa cv. Vera, e a influência dessas adubações sobre a vida útil pós-colheita da hortaliça, em condições de laboratório. Esses fertilizantes foram empregados em cobertura e comparados com cama-de-aviário industrial, assegurando-se doses equivalentes de N total. O delineamento experimental foi o de blocos ao acaso, com cinco tratamentos e quatro repetições: T1: adubação pré-plantio, com termofosfato sílico-magnesiano + sulfato de potássio; T2: T1 + esterco bovino, em pré-plantio; T3: T2 + fertilizante de mucuna-cinza, em cobertura; T4: T2 + fertilizante de gliricídia, em cobertura; T5: T2 + cama-de-aviário em cobertura. Não houve diferença entre os fertilizantes de ambas as espécies de leguminosas e a cama-de-aviário, quanto à produtividade, teor de N, padrão comercial e período de vida útil pós-colheita das alfaces, o que indica potencial de uso desses fertilizantes como fontes de N para sistemas orgânicos de produção de hortaliças.The objective of this work was to evaluate the potential use of two legume fertilizers - products derived from cutting, dehydration and milling of the aerial biomass of legume plants, velvet bean (Mucuna pruriens and gliricidia (Gliricidia sepium - as alternative sources of N for organic production of lettuce (Lactuca sativa cv. Vera; and to evaluate the influence of soil fertilization on lettuce shelf life at laboratory bench condition. These fertilizers were applied on soil surface and compared to factory poultry-bed manure at equivalent total N doses. The experimental design consisted of randomized blocks with five treatments and four replications, as

  5. Resposta de cultivares de alface à salinidade da solução nutritiva com rejeito salino em hidroponia Response of lettuce cultivars to nutrient solution salinity with saline rejects in hydropony

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    Nildo da S Dias

    2011-10-01

    Full Text Available No processo de dessalinização se gera, além da água potável, um rejeito altamente salino e de poder poluente elevado, o qual pode ser utilizado na produção agrícola rentável dependendo da adoção de práticas culturais adequadas e da tolerância das plantas às condições salinas. Nos últimos anos a tendência tem sido a substituição da agricultura convencional por sistemas hidropônicos de cultivos, considerados um dos mais eficientes no uso de água. O objetivo desta pesquisa foi analisar a resposta de duas cultivares de alface sob sistema hidropônico de cultivo (Lactuca sativa L., cvs. Verônica e Babá de verão em diferentes níveis de salinidade da solução nutritiva preparadas com água de abastecimento, água de rejeito coletada no dessalinizador e da sua diluição com água de abastecimento a 75, 50 e 25%, resultando em condutividades elétricas da solução nutritiva (CEs de 1,1; 2,4; 3,6; 4,7 e 5,7 dS m-1 após as diluições e adição de fertilizantes. Ocorreu variação genotípica sob as variáveis de crescimento e produção da alface, exceto para o número de folhas, sendo a cultivar Babá de verão a que produziu maior rendimento, independentemente do nível de salinidade e, portanto, a cultivar mais tolerante à salinidade da água com rejeito salino.In desalination process, besides the potable water, highly salty and polluted water (brine is generated, which can be used for producing profitable crops depending on the adequate cultural practices as well as on the plant ability of reacting to saline conditions. The trend in recent years has been towards conversion of conventional agriculture to soilless agriculture which is considered to be a more efficient use of water system. The aim of this research was to examine the response of two lettuce cultivars (Lactuca sativa L. cvs. Veronica, Babá de verão under hydroponic system to different levels of salinity of the nutrient solutions prepared with tap water

  6. Produção de mudas de alface com o uso de substrato preparado com coprólitos de minhoca Prodution of seedlings of lettuce with the use of prepared substrate with earthworm casting

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    Suzana Rodrigues de Souza

    2008-02-01

    Full Text Available Com o objetivo de avaliar o efeito de coprólitos de minhoca (Chibui bari Righi & Guerra, 1985 na produção de mudas de alface (Lactuca sativa L. cv. Simpson, realizaram-se dois experimentos em casa de vegetação na Universidade Federal do Acre, ambos no delineamento experimental inteiramente casualizado, com seis tratamentos e seis repetições, totalizando 36 unidades experimentais, representadas por copos plásticos de 180 cm³. Os tratamentos foram definidos a partir da mistura de seis concentrações (0, 20, 40, 60, 80 e 100% de solo e coprólitos. Utilizaram-se dois tipos de solo, eutrófico no experimento 1 e distrófico no experimento 2. Aos 34 dias após a semeadura avaliaram-se a matéria seca da parte aérea, da raiz e total da planta. Os resultados do experimento 1 indicam que o acréscimo de coprólitos a solos eutróficos promove máximo incremento de massa seca da parte aérea e total da planta com concentrações de coprólitos de 13,49% e 17,88%, respectivamente. Entretanto, os resultados do experimento 2 indicam que a adição de coprólitos a solos distróficos, responde a uma função cúbica, com máximo incremento de massa seca da raiz e total da planta com concentrações de coprólitos de 17,49% e 21,40%, respectivamente, com decréscimo em 68,23% e 67,48%, e incremento máximo novamente com 100% de coprólitos para ambas características. O uso de substratos preparados com solo e coprólitos de minhoca somente contribui para o crescimento de mudas de alface se a condição química dos coprólitos for mais adequada que a do solo em atender as necessidades nutricionais das plantas.With the aim of evaluating the effect of earthworm casting (Chibui bari Righi & Guerra, 1985 in the production of lettuce seedlings (Lactuca sativa L. cv. Simpson, two experiments ware carried out in greenhouse in the Federal University of the Acre, both in a completely randomized outline with six treatments and six repetitions, totalizing 36

  7. Models to estimate phytomass accumulation of hydroponic lettuce Modelos para estimar o acúmulo de fitomassa de alface em hidroponia

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    Sidinei José Lopes

    2004-01-01

    Full Text Available The protected and hydroponics cultivation are increasing in Brazil, demanding a better knowledge of crop performance in this environment. Plant dry matter accumulation as a function of solar radiation, temperature, relative humidity and other weather parameters in greenhouse is different when compared with field cultivation. With the purpose of proposing models to characterize the temporal variation of leaf and total dry matter production of hydroponics-grown lettuce (Lactuca sativa L. and to determine the flowering period and the maximum dry matter accumulation rate as a function of plant relative development (relative degree-days, solar radiation and effective thermal index, two experiments (Spring and Autumn were carried out in the greenhouse, at Santa Maria, Rio Grande do Sul State, Brazil. Growth and development models are useful in obtaining basic information on the plant ´ environment interactions, maximizing the use of resources in greenhouse, as well as, to define the best form of crop management. The cultivar Vera was chosen as function of its earliness. Models were proposed to estimate the temporal variation of dry matter accumulation, where the best results for relative development were obtained using effective degree-days, characterizing the importance of the air temperature for the vegetative phase and the solar radiation for the reproductive. The yield and quality of the lettuce seeds evidenced a high potential of hydroponics technique.O cultivo protegido e o cultivo hidropônico de plantas estão sendo cada vez mais utilizados no Brasil, exigindo maior conhecimento sobre as respostas das plantas nesses ambientes. O acúmulo de massa seca de plantas em cultivo protegido é função da radiação solar, temperatura, umidade e outros elementos climáticos, e é diferente quando comparado com o cultivo a campo. Com o objetivo de propor modelos para caracterizar a variação temporal na massa seca de folhas e total da cultura de

  8. Comportamento da alface americana em função do uso de doses e épocas de aplicação de boro em cultivo de inverno Behavior of crisp head lettuce as a result of doses and application times of boron in winter crop

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    Jony E. Yuri

    2004-09-01

    Full Text Available Avaliou-se a influência de doses de bórax sobre o rendimento e qualidade pós-colheita da alface americana (Lactuca sativa L., em três ensaios distintos conduzidos de junho a agosto/2002, no município de Três Pontas (MG. Utilizou-se o delineamento de blocos ao acaso com cinco doses de bórax (0,00; 0,75; 1,50; 2,25 e 3,00 kg ha-1 e quatro repetições, aplicadas em três diferentes épocas via foliar (14; 21 e 28 dias após o transplantio. A massa fresca total apresentou efeito quadrático no qual a dose de 1,58 kg ha-1 de bórax resultou em maior rendimento. Verificou-se variação de 795 a 829 g planta-1 entre as épocas de aplicação, sem diferirem estatisticamente entre si. A aplicação de 1,71 kg ha-1 de bórax possibilitou a obtenção de maior massa fresca comercial. O melhor resultado (563 g planta-1 foi obtido na aplicação aos 21 dias. Esta data também contribuiu na obtenção de maior circunferência da cabeça (41,7 cm, sendo significativamente superior à aplicação aos 28 dias (40,6 cm. Não foram observados efeitos significativos para o comprimento de caule entre os tratamentos. A dose de 1,55 kg ha-1 de bórax proporcionou uma melhor conservação da alface mantida durante 20 dias em câmara-fria.The influence of doses of borax on yield and post harvest quality of crisp head lettuce (Lactuca sativa L. was evaluated. Three distinct trials were conducted in Tres Pontas, Minas Gerais State, Brazil, from June to August 2002. The randomized block design with five doses of borax (0.00; 0.75; 1.50; 2.25 and 3.00 kg.ha-1 and four replicates, applied foliarly at different times (14; 21 and 28 days after transplanting was evaluated. The total fresh matter presented a quadratic effect, where the dose of 1.58 kg ha-1 of borax resulted in a greater yield. A range of 795 to 829 g plant-1 between different application times, with no statistical significant differences was observed. The application of 1.71 kg ha-1 of borax resulted in

  9. Efectos alelopáticos de extractos acuosos de hojas de botón de oro [Tithonia diversifolia (Hemsl. A. Gray.] sobre la germinación de semillas y crecimiento de plántulas de lechuga (Lactuca sativa L.

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    José Alberto Laynez Garsaball

    2013-01-01

    Full Text Available Algunos compuestos químicos liberados por las plantas tienen la capacidad de controlar la presencia de otras plantas en su entorno tanto de su propia especie como de otras, la alelopatía es un factor de importancia en la regulación de la estructura de las comunidades vegetales, resultando crucial para un apropiado desarrollo agrícola un mejor entendimiento de estas relaciones. La investigación tuvo por objeto determinar los efectos de extractos acuosos del follaje del botón de oro (Tithonia diversifolia sobre germinación de semillas y crecimiento de plántulas de lechuga (Lactuca sativa L., cultivar Parris Island. Se preparó un extracto al 15 % p/v con hojas de plantas de botón de oro, se dejó reposar por 48 h y luego se obtuvo por dilución extractos al 0,5; 1,0; 1,5 y 2,0 % p/v evaluándoseles pH y conductividad eléctrica (S.cm-1. La siembra se realizó en bandejas cubiertas con una doble capa de papel absorbente sobre la que se colocó 25 semillas/bandeja. Fueron regadas dos veces diarias con los extractos foliares. El tratamiento control recibió agua corriente. El diseño estadístico fue bloques completos al azar con cuatro repeticiones. La cosecha de las plántulas se efectuó a los 14 días después de la siembra. El pH disminuyó y la conductividad eléctrica se incrementó con los aumentos en la concentración de los extractos foliares. La germinación se vio afectada negativamente por los extractos. Se demostró un efecto reductor sobre el crecimiento general de las plántulas de lechuga.

  10. Produção de mudas de alface em substrato alternativo com adubação Production of lettuce seedlings using alternative substrates and fertilizer

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    Luiz Antonio Augusto Gomes

    2008-09-01

    Full Text Available Substratos alternativos, além de permitirem a produção de mudas de qualidade, reduzem os custos de produção. Neste trabalho avaliou-se a produção de mudas de alface (Lactuca sativa L. utilizando misturas de casca de arroz carbonizada e húmus de minhoca com diferentes doses de SulPoMag®. O trabalho foi desenvolvido nas instalações da HortiAgro Sementes Ltda, em Ijaci (MG. Utilizou-se o delineamento de blocos casualizados, com cinco tratamentos e quatro repetições, sendo os tratamentos 1: 70% de húmus de minhoca (HM e 30% de casca de arroz carbonizada (CAC, adicionados de 12,2 g de fosfato de Arad (FA por litro da mistura, e tratamentos 2, 3 e 4: com as mesmas quantidades de HM, CAC, e FA, adicionadas, respectivamente, de 2,0; 4,0 e 8,0 g de SulPoMag®. Como testemunha utilizou-se o substrato comercial Bioplant®. Avaliaram-se as características de massa fresca de parte aérea (MFPA e raiz (MFRZ; massa seca de parte aérea (MSPA e raiz (MSRZ; teor de matéria seca de parte aérea (TMSPA e raiz (TMSRZ e condutividade elétrica (CE em dS m-1 dos substratos. O substrato comercial e o tratamento 1 apresentaram maiores valores de MFPA e MSPA. Os outros tratamentos, independentemente das doses de SulPoMag®, não diferiram entre si para MFPA. Para MSPA, o comportamento foi o mesmo, à exceção do tratamento 3, que foi semelhante ao tratamento 1 e ao substrato comercial. O aumento das doses de SulPoMag® resultou em uma elevação da condutividade elétrica para todos os tratamentos de forma linear. A produção de mudas de alface semelhante àquela obtida com o substrato comercial é viável, utilizando-se matéria prima obtida na propriedade. A produção de MFPA foi afetada negativamente pela adição de SulPoMag® ao substrato.Alternative substrates, besides allowing the production of quality seedlings, reduce the production costs. In this work we evaluated the production of lettuce seedlings (Lactuca sativa L. using mixtures of

  11. Specific in planta recognition of two GKLR proteins of the downy mildew Bremia lactucae revealed in a large effector screen in lettuce.

    Science.gov (United States)

    Stassen, Joost H M; den Boer, Erik; Vergeer, Pim W J; Andel, Annemiek; Ellendorff, Ursula; Pelgrom, Koen; Pel, Mathieu; Schut, Johan; Zonneveld, Olaf; Jeuken, Marieke J W; Van den Ackerveken, Guido

    2013-11-01

    Breeding lettuce (Lactuca sativa) for resistance to the downy mildew pathogen Bremia lactucae is mainly achieved by introgression of dominant downy mildew resistance (Dm) genes. New Bremia races quickly render Dm genes ineffective, possibly by mutation of recognized host-translocated effectors or by suppression of effector-triggered immunity. We have previously identified 34 potential RXLR(-like) effector proteins of B. lactucae that were here tested for specific recognition within a collection of 129 B. lactucae-resistant Lactuca lines. Two effectors triggered a hypersensitive response: BLG01 in 52 lines, predominantly L. saligna, and BLG03 in two L. sativa lines containing Dm2 resistance. The N-terminal sequences of BLG01 and BLG03, containing the signal peptide and GKLR variant of the RXLR translocation motif, are not required for in planta recognition but function in effector delivery. The locus responsible for BLG01 recognition maps to the bottom of lettuce chromosome 9, whereas recognition of BLG03 maps in the RGC2 cluster on chromosome 2. Lactuca lines that recognize the BLG effectors are not resistant to Bremia isolate Bl:24 that expresses both BLG genes, suggesting that Bl:24 can suppress the triggered immune responses. In contrast, lettuce segregants displaying Dm2-mediated resistance to Bremia isolate Bl:5 are responsive to BLG03, suggesting that BLG03 is a candidate Avr2 protein.

  12. Desempenho de cultivares de alface tipo americana em cultivo de outono no sul de Minas Gerais Performance of iceberg lettuce cultivars in south of Minas Gerais under autumn condition

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    Jony Eishi Yuri

    2004-04-01

    Full Text Available Com o objetivo de avaliar o desempenho de cultivares de alface tipo americana (Lactuca sativa L. em cultivo de outono, foi conduzido um experimento no município de Santana da Vargem, MG, no período de março a junho de 2002. Utilizou-se o delineamento de blocos ao acaso com treze tratamentos (cultivares Adal, 4553 R7, AEL 10, Iglo, Rocco RZ, Rubette, RX 66, RPT 3030, RPT 2020, Paloma, Sandy, Legacy e Raider e três repetições. As cultivares 45-53R7, RPT 2020, Paloma, Raider e RPT 3030 apresentaram massa fresca total estatisticamente maiores que as demais cultivares, com produtividades de 1.016,9; 1.029,4; 1.044,9; 1.075,2 e 1.105,2 g planta-1, respectivamente. As cultivares 45-53R7, RPT 2020, Paloma, Raider, RPT 3030, AEL 10 e Rocco, com produtividade de massa fresca comercial oscilando entre 599,1 a 739,1 g planta-1, foram estatisticamente mais produtivas que as demais cultivares. A cultivar 45-53R7, com circunferência de cabeça comercial de 49,2 cm, sobressaiu-se das demais. Não houve diferenças significativas entre os materiais quanto ao comprimento de caule. Quanto à simetria da cabeça comercial, as cultivares RPT 2020, Raider e RPT 3030, com notas 4,6; 5,0 e 5,0, respectivamente, foram mais simétricas do que as demais cultivares.With the objective of evaluating iceberg lettuce (Lactuca sativa L. cultivars grown under autumn condition, an experience in Santana da Vargem, MG, Brazil, was carried out from March to June of 2002. The experimental design was in randomized complete blocks with thirteen treatments (cultivars Adal, 4553 R7, AEL 10, Iglo, Rocco RZ, Rubette, RX 66, RPT 3030, RPT 2020, Paloma, Sandy, Legacy e Raider and three replicates. The cultivars 45-53R7, RPT 2020, Paloma, Raider and RPT 3030 showed statistically higher total fresh matter than the other cultivars, with the yield ranging 1,010.9; 1,029.4; 1,044.9; 1,075.2 and 1105.2 g plant-1, respectively. The cultivars 45-53R7, RPT 2020, Paloma, Raider, RPT 3030, AEL

  13. Effector identification in the lettuce downy mildew Bremia lactucae by massively parallel transcriptome sequencing.

    Science.gov (United States)

    Stassen, Joost H M; Seidl, Michael F; Vergeer, Pim W J; Nijman, Isaäc J; Snel, Berend; Cuppen, Edwin; Van den Ackerveken, Guido

    2012-09-01

    Lettuce downy mildew (Bremia lactucae) is a rapidly adapting oomycete pathogen affecting commercial lettuce cultivation. Oomycetes are known to use a diverse arsenal of secreted proteins (effectors) to manipulate their hosts. Two classes of effector are known to be translocated by the host: the RXLRs and Crinklers. To gain insight into the repertoire of effectors used by B. lactucae to manipulate its host, we performed massively parallel sequencing of cDNA derived from B. lactucae spores and infected lettuce (Lactuca sativa) seedlings. From over 2.3 million 454 GS FLX reads, 59 618 contigs were assembled representing both plant and pathogen transcripts. Of these, 19 663 contigs were determined to be of B. lactucae origin as they matched pathogen genome sequences (SOLiD) that were obtained from >270 million reads of spore-derived genomic DNA. After correction of cDNA sequencing errors with SOLiD data, translation into protein models and filtering, 16 372 protein models remained, 1023 of which were predicted to be secreted. This secretome included elicitins, necrosis and ethylene-inducing peptide 1-like proteins, glucanase inhibitors and lectins, and was enriched in cysteine-rich proteins. Candidate host-translocated effectors included 78 protein models with RXLR effector features. In addition, we found indications for an unknown number of Crinkler-like sequences. Similarity clustering of secreted proteins revealed additional effector candidates. We provide a first look at the transcriptome of B. lactucae and its encoded effector arsenal. © 2012 THE AUTHORS. MOLECULAR PLANT PATHOLOGY © 2012 BSPP AND BLACKWELL PUBLISHING LTD.

  14. Fungitoxicidade, atividade elicitora de fitoalexinas e proteção de alface em sistema de cultivo orgânico contra Sclerotinia sclerotiorum pelo extrato de gengibre Fungitoxicity, phytoalexins elicitor activity and protection of grown against Sclerotinia sclerotiorum by ginger extract

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    Edvirgem Rodrigues

    2007-06-01

    Full Text Available O patógeno Sclerotinia sclerotiorum é um fungo que sobrevive no solo e causa a doença conhecida como mofo branco ou podridão de esclerotínia na cultura da alface (Lactuca sativa e outras culturas. A doença é considerada de difícil controle, uma vez que o fungo é muito agressivo e produzem estruturas de resistência, os escleródios. Na busca de novos métodos de controle de doenças, os extratos de plantas com propriedades terapêuticas surgem como opção. Neste trabalho avaliou-se o efeito do extrato bruto aquoso (EBA de gengibre (Zingiber officinalis nas concentrações de 1, 5, 10, 15, 20 e 25% sobre o crescimento micelial e produção de escleródios de S. sclerotiorum, in vitro. Também foi verificada a eficiência do gengibre na proteção de plantas de alface cultivadas organicamente e inoculadas com o patógeno. Além da incidência da doença, foi analisado o rendimento da cultura e a atividade de peroxidase nos tecidos da planta. Água e o indutor de resistência acibenzolar-S-metil foram utilizados como tratamentos controle. Adicionalmente, a capacidade elicitora do EBA de gengibre em proporcionar o acúmulo das fitoalexinas deoxiantocianidina e gliceolina foi avaliada em bioensaios com sorgo e soja, respectivamente. Os resultados indicaram a atividade antimicrobiana dos EBA de gengibre, com inibição do crescimento micelial e da produção de escleródios. Na cultura da alface, verificou-se que a aplicação de massa de gengibre na base da planta aumentou a atividade da enzima peroxidase e reduziu a incidência da doença. A presença de compostos elicitores no EBA de gengibre foi observada pela indução da produção de fitoalexinas em sorgo e soja, que ocorreu de maneira dose-dependente. Estes resultados indicam o potencial de Z. officinalis para o controle de S. sclerotiorum em alface, o qual pode ocorrer tanto por atividade antimicrobiana direta quanto pela ativação de mecanismos de defesa das plantas

  15. Levantamento de raças do agente causador do míldio da alface no Estado de São Paulo em 2012 e 2013

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    Renata de Castro Nunes

    2016-03-01

    Full Text Available RESUMO A alface é, entre as hortaliças folhosas, a mais importante economicamente para o Brasil. No inverno, com baixas temperaturas e com molhamento foliar, o míldio da alface, doença causada pelo agente etiológico Bremia lactucae, ocorre em praticamente todas as regiões de cultivo desta hortaliça, sendo considerada uma das doenças foliares mais severas da cultura. O objetivo deste trabalho foi identificar as raças de B. lactucae no ano de 2012 e 2013 que ocorreram nas principais regiões produtoras do Estado de São Paulo, como: Ribeirão Preto, Jaboticabal, Pirangi, Catanduva, São José do Rio Preto, Atibaia, Salesópolis, Biritiba Mirim, Mogi das Cruzes, Campinas, Itapira, Mogi Mirim, Cândido Mota, Presidente Prudente, Echaporã, Assis, Marília, Botucatu e Bauru. Durante o mês de julho/agosto de 2012 e 2013, coletaram-se amostras de folhas de alface com sintomas de míldio, sendo que, em cada amostra coletada, as estruturas do patógeno referiram-se a um isolado. Os esporângios foram multiplicados na cultivar suscetível Solaris, com posterior inoculação nas cultivares diferenciadoras, realizando-se as avaliações no 12º dia do aparecimento da primeira esporulação na cultivar suscetível ‘Green Tower’ (Dm-0, conforme o código “Sextet”. Em 2012, foi determinado dois novos códigos, identificando duas novas raças, SPBl:10 (63/31/02/00 e SPBl:11 (63/63/18/00. Em 2013, uma nova codificação foi determinada (63/31/18/00, à qual propôs a denominação de SPBl:12. Os genes Dm-14 e Dm-15, e os fatores de resistência FR-17, FR-18, FR-36, FR-37 e FR-38 conferem resistência a essas novas raças identificadas. Recomenda-se, portanto, em programas de melhoramento genético de alface, a utilização dos fatores FR-17, FR-18 e FR-38 como fontes de resistência para novas cultivares desenvolvidas para cultivo no Estado de São Paulo, por conferirem resistência a todas as 12 raças já identificadas.

  16. Doses de nitrogênio e molibdênio no rendimento e teor de micronutrientes em alface americana Doses of nitrogen and molybdenum effects on yield and micronutrient content of crisphead lettuce plants

    Directory of Open Access Journals (Sweden)

    Geraldo M de Resende

    2010-09-01

    Full Text Available O trabalho foi conduzido no município de Três Pontas, Sul de Minas Gerais, de outubro a dezembro de 2002, com o objetivo de avaliar a influência de doses de nitrogênio (N e molibdênio (Mo no rendimento e teor de micronutrientes da alface americana. Utilizou-se o delineamento de blocos casualizados em arranjo fatorial 4 x 5, compreendendo quatro doses de N (0, 60, 120 e 180 kg ha-1 em cobertura adicionais à dose aplicada pelo produtor de 60 kg ha-1 e cinco doses de Mo via foliar (0,0; 35,1; 70,2; 105,3 e 140,4 g ha-1 com três repetições. O maior rendimento de massa fresca comercial foi obtido com a dose de 89,1 kg ha-1 de N em cobertura e 94,2 g ha-1 de Mo. Os resultados indicaram incremento nos teores de boro, zinco, ferro e manganês com o aumento das doses de N e Mo. Em relação ao teor de cobre verificou-se efeito significativo da interação N x Mo, evidenciando para a maior dose de Mo (140,4 g ha-1 uma redução linear com o aumento das doses de N.The trial was carried out in Três Pontas, Minas Gerais State, Brazil, from October to December, 2002, to evaluate the influence of doses of nitrogen and molybdenum on yield and macronutrient uptake of crisphead lettuce (Lactuca sativa L.. A randomized complete block design scheme with three replications was used, in which the treatments were a factorial combination of nitrogen rates (0, 60, 120 and 180 kg ha-1 of N in top dressing in addition to the dose used by farmers (60 kg ha-1 of N and five foliar molybdenum rates (0.0; 35.1; 70.2; 105.3 and 140.4 g ha-1. The highest yield of commercial fresh mass was obtained using the dose of 89.1 kg ha-1 of nitrogen in top dressing and 94.2 g ha-1 of molybdenum. The results indicated an increase in the levels of Ca, Zn, Fe and Mn as a consequence of the application of higher doses of nitrogen and molybdenum. Significant effect of the interaction N x Mo on the Cu level was verified and it was evidenced, for the highest molybdenum level (140.4 g

  17. Pengaruh Bokhasi Eceng Gondok pada Tanaman Selada (Lactuca sativa L.

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    Seprita Lidar

    2016-03-01

    Full Text Available Isu pertanian organik akhir-akhir ini memang mulai berkembang kembali dengan semakin banyaknya masyarakat yang menyadari pentingnya kesehatan dan mutu bahan pangan yang dikonsumsi. Selain alasan kesehatan, pertanian organik juga diyakini ramah lingkungan karena dapat meminimalkan penggunaan bahan kimia dalam proses produksinya, karena penggunaan pupuk kimia secara terus-menerus dengan dosis yang meningkat justru dapat menyebabkan tanah menjadi keras dan keseimbangan unsur hara tanah terganggu.  Permintaan pasar terhadap tanaman sayuran khususnya selada yang biasanya dikonsumsi mentah terus meningkat, apalagi tanaman selada yang dipupuk dengan pupuk organik. Tanah di Kota Pekanbaru tergolong tanah Podsolid Merah Kuning (PMK yang kandungan bahan organik dan unsur haranya relatif rendah, maka salah satu usaha untuk mengatasi masalah tersebut adalah dengan cara pemupukan yang aman bagi tanaman dan tanah yaitu pupuk bokhasi eceng gondok yang mengandung unsur hara N, P dan K, juga memanfaatkan yang ada di lingkungan yang kalau tidak dimanfaatkan akan menyebabkan pencemaran di perairan.  Dari penelitian yang dilakukan pemberian bokhasi eceng gondok berpengaruh nyata terhadap pertumbuhan dan produksi tanaman selada dengan dosis terbaik adalah 2000 g/m2. Kata Kunci : Selada, Bokhasi, Eceng Gondok.The issue of organic farming lately indeed began to grow back more and more people will realize the importance of health and quality of food consumed. In addition to health reasons, organic farming is also believed to be environmentally friendly because it can minimize the use of chemicals in the production process, due to the use of chemical fertilizers continuously with increasing doses it can cause the soil to be loud and disturbed soil nutrient balance. Market demand for vegetable crops, especially lettuce is usually consumed raw continue to rise, especially lettuce plants are fertilized with organic fertilizer. Land in the city of Pekanbaru classified as land Podsolid Red Yellow (FMD is organic matter content and nutrient relatively low, then one attempt to overcome this problem is by fertilizing safe for plants and soil is fertilizer bokhasi hyacinth that contains nutrients N , P and K, also take advantage of in the environment that would otherwise be used will cause pollution in the waters. From research conducted bokhasi provision of water hyacinth significantly affect the growth and production of lettuce plants with the best dose is 2000 g / m2. Keywords: Lettuce, Bokhasi, Water Hyacinth.

  18. Irradiation of lettuce (Lactuca sativa. L.): microbiological and sensory aspects

    International Nuclear Information System (INIS)

    Tsuhako, Vanessa Provenzano

    2005-01-01

    The increasing demand for fresh foods have stimulated the marketing of minimally processed vegetables. However, these products maintain most of their natural microbiota even after being sanitized, including pathogenic microorganisms. Refrigerated storage allows the growth of psychotropic microorganisms and among them the pathogen Listeria monocytogenes. The ingestion of food contaminated with L. monocytogenes may represent a risk to pregnant women and their fetuses and to immunocompromised people. Non-thermal alternative processes for food preservation, such as irradiation, can reduce pathogenic and spoilage microorganism populations without impairing substantial changes in sensory, physical or chemical attributes. The aims of this research were to evaluate the effect of gamma radiation on L. monocytogenes artificially inoculated on minimally processed lettuce, to evaluate its effect on lettuce leaves through acceptance sensory test and to determine the irradiated vegetable shelf life through sensory and microbiological tests. A mixture of 4 types of lettuce (Iceberg, Boston, Loose-leaf and Red loose-leaf) were artificially inoculated with L. monocytogenes (7 log UFC/g lettuce) and then exposed to 0.3; 0.6; 0.9 and 1.2 kGy, under refrigeration. The DlO values for L. monocytogenes varied fram 0.18 to 0.21 kGy. Sensory and microbiological tests indicated that the shelf life of Iceberg lettuce stored at 7 deg C was 5 and 7 days for the irradiated and non-irradiated samples, respectively, and for the irradiated and non-irradiated Loose-leaf lettuce samples were 10 days. For the non-irradiated Boston sample, the shelf life was 3 days and for the Irradiated 7 days. Red loose-leaf showed 5 and 4 days of shelf lives for the irradiated and non-irradiated, respectively. Irradiated samples presented better microbiological quality than non-irradiated ones. The irradiation is feasible process to improve quality and safety of lettuce leaves. (author)

  19. Research of determinants controlling cadmium accumulation in lettuce "Lactuca sativa".

    OpenAIRE

    Zorrig, Walid

    2011-01-01

    Les activités humaines agricoles, urbaines et industrielles, sans cesse croissantes, sont à l'origine d'une contamination de notre environnement par les métaux lourds. Alors que de nombreuses molécules organiques peuvent être dégradées, les métaux lourds ne le peuvent pas et leur concentration augmente régulièrement dans les sols et les eaux. Ceci expose les plantes à des concentrations croissantes de métaux lourds. L’accumulation de métaux lourds dans les plantes présente un risque toxique p...

  20. Acinetobacter lactucae sp. nov., isolated from iceberg lettuce (Asteraceae: Lactuca sativa)

    Science.gov (United States)

    Strain NRRL B-41902 and three closely related strains were isolated from iceberg lettuce. The strain was found to consist of strictly aerobic, gram-negative rods that formed cocci in late stationary phase. Subsequent to sequencing the 16S ribosomal RNA gene, it was found that strain NRRL B-41902 was...

  1. Produção de alface-americana, em função de doses e épocas de aplicação de zinco Iceberg lettuce production in function of doses and application time of zinc

    Directory of Open Access Journals (Sweden)

    Jony Eishi Yuri

    2006-08-01

    Full Text Available Com o objetivo de avaliar a influência de doses de sulfato de zinco sobre a da alface- americana (Lactuca sativa L., foram conduzidos três experimentos distintos entre os meses de maio e julho de 2002, no município de Três Pontas - MG. Utilizou-se o delineamento de blocos ao acaso, com cinco doses de sulfato de zinco (0; 0,9; 1,8; 2,7 e 3,6 kg ha-1 e 4 repetições, aplicadas em três diferentes épocas via foliar (14, 21 e 28 dias após o transplante. Foram avaliadas as características massa fresca total e comercial (g planta-1, circunferência da cabeça comercial (cm e comprimento do caule da cabeça comercial (cm. As características massa fresca total e comercial evidenciaram efeitos significativos independentes para as doses de sulfato de zinco e épocas de aplicação Para massa fresca total, a dose de 2,01 kg ha-1 de sulfato de zinco proporcionou o maior rendimento. Em relação à época de aplicação, essa característica apresentou o maior rendimento (988 g planta-1 quando a pulverização foi realizada aos 14 dias. Em termos de massa fresca comercial, a dose de 2,09 kg ha-1 propiciou o maior rendimento, sendo a aplicação aos 14 dias, estatisticamente superiores, com rendimentos de 593 g planta-1. Para circunferência de cabeça, a dose de 2,63 kg ha-1 de sulfato de zinco proporcionou o maior retorno. Não se observou efeitos significativos dos tratamentos para comprimento do caule.With the objective of evaluating the influence of doses of zinc sulphate on yield and quality of iceberg lettuce (Lactuca sativa L., three distinct trials were carried out at Três Pontas, State of Minas Gerais, Brazil, from May to June of 2002. The experimental design was randomized blocks with five doses of zinc sulphate (0, 0.9, 1.8, 2.7 and 3.6 kg ha-1, applied to the foliage at three different application times (14, 21 and 28 days after transplanting, and four replicates. The characteristics total and commercial fresh mass (g plant-1

  2. Produtividade e qualidade pós-colheita da alface americana em função de doses de nitrogênio e molibdênio Yield and postharvest quality of summer growing crisphead lettuce as affected by doses of nitrogen and molybdenum

    Directory of Open Access Journals (Sweden)

    Geraldo M. de Resende

    2005-12-01

    Full Text Available O trabalho foi conduzido no município de Três Pontas (MG, de outubro a dezembro de 2002, para avaliar a influência de doses de nitrogênio e molibdênio nas características produtivas e qualidade pós-colheita da alface americana (Lactuca sativa L.. Utilizou-se o delineamento de blocos ao acaso em arranjo fatorial 4 x 5, compreendendo quatro doses de nitrogênio em cobertura adicionais à dose aplicada pelo produtor de 60 kg/ha de N (0; 60; 120 e 180 kg/ha e cinco doses de molibdênio via foliar (0,0; 35,1; 70,2; 105,3 e 140,4 g/ha e três repetições. O maior peso fresco total foi obtido com a dose de 86,9 kg/ha de nitrogênio em cobertura e 87,4 g/ha de molibdênio. Com relação ao peso fresco comercial a dose de 89,1 kg/ha de nitrogênio em cobertura propiciou a maior resposta, sendo para molibdênio a máxima produtividade alcançada com a dose de 94,2 g/ha. As doses de 85,3 kg/ha de nitrogênio em cobertura e 72,9 g/ha de molibdênio proporcionaram a maior circunferência de cabeça comercial. Não se observou efeito significativo dos tratamentos para comprimento do caule e na conservação pós-colheita. As doses de 89,9 kg/ha de N em cobertura e 77,2 g/ha de Mo em pulverização foliar propiciaram a maior porcentagem de matéria seca.The influence of nitrogen and molybdenum doses was evaluated on the productive characteristics and postharvest quality of crisphead lettuce (Lactuca sativa L., at Três Pontas, Minas Gerais State, Brazil, from October to December 2002. A randomized complete block design in a 4 x 5 factorial arrangement with three replications was used. The factorial consisted of four doses of nitrogen (0; 60; 120 and 180 kg/ha in top dressing, in addition to the usual farmers doses (60 kg/ha, and five doses of molybdenum in foliar application (0.0; 35.1; 70.2; 105.3, and 140.4 g/ha. The highest total fresh weight was obtained with the doses of 86.9 kg/ha of nitrogen in top dressing and 87.4 g/ha of molybdenum. Highest

  3. Influência da condutividade elétrica, concentração iônica e vazão de soluções nutritivas na produção de alface hidropônica Effect of electric conductivity, ionic concentration and flow of nutrient solutions in the production of hidroponic lettuce

    Directory of Open Access Journals (Sweden)

    Celso Helbel Junior

    2008-08-01

    Full Text Available Objetivou-se, neste trabalho, estudar os efeitos de diferentes soluções nutritivas aplicadas em duas vazões na produção hidropônica da alface (Lactuca sativa, cultivada pelo sistema NFT (Nutritive Film Technique. O experimento foi conduzido em casa de vegetação, na unidade de pesquisa em agricultura irrigada da Universidade Estadual de Maringá. Os tratamentos constaram de três soluções nutritivas com concentrações diferentes (S1=0,8 dS/m, S2=1,2 dS/m e S3=2,5 dS/m, combinadas com duas vazões de aplicação (V1=0,8 L.min-1 e V2=1,2 L.min-1 nos canais de cultivo em esquema fatorial 3 x 2. Para avaliar o efeito dos tratamentos no desenvolvimento da cultura os dados foram submetidos à análise de variância (teste F, e os resultados avaliados através de teste de média de Tukey (5%. A análise dos resultados permitiu concluir que os fatores solução e vazão não apresentaram interação significativa e que os maiores valores avaliados de biomassa fresca e diâmetro do caule foram obtidos no tratamento solução 2 (CE= 1,2 dS/m.The porpose of this work was to study the effect of different nutrient solutions applied in two outflow in the hidroponic yeld of lettuce (Lactuca sativa. This research was accomplished at greenhouse through hydroponic system NFT in Maringá State University. The treatments consisted of three nutrient solutions (S1=0,8 dS/m, S2=1,2 dS/m e S3=2,5 dS/m combined with two flows of application (V1=0,8 L.min-1 e V2=1,2 L.min-1 in the growing channels of cultivation. The flows of application of the solutions were 0,8 L.min-1 (V1 and 1,2 L.min-1 (V2, placed alternately in the growing channels in a 3 x 2 factorial scheme. To evaluate the effect of treatments on the culture development the data were submitted to the variance analysis (Test F, and the results were evaluated through Tukey (5% average test. The analysis of the results allowed to conclude that the factories nutrient solution and flow did not show

  4. Efeitos da cobertura do solo com filme de polietileno azul no consumo de água da cultura da alface cultivada em estufa Effects of the soil covering with blue colored polyethylene film on lettuce crop consumptive water-use in a gree

    Directory of Open Access Journals (Sweden)

    Alexandre O. Gonçalves

    2005-12-01

    Full Text Available A cobertura do solo é uma prática agrícola que visa, principalmente, a controlar as plantas invasoras, a diminuir as perdas de água por evaporação do solo e a facilitar a colheita e a comercialização, uma vez que o produto se torna mais limpo e sadio. Porém, ao se cobrir o solo, também são alterados parâmetros importantes do microclima e, conseqüentemente, a germinação das sementes, o crescimento das raízes, a absorção de água e nutrientes, a atividade metabólica das plantas e o armazenamento de carboidratos. O objetivo do presente trabalho foi avaliar o efeito da cobertura do solo com filme de polietileno azul no consumo de água da cultura da alface (Lactuca sativa L.. O experimento foi instalado em uma estufa convencional, no município de Araras - SP, e conduzido durante o período de 22-3-2001 a 1º-5-2001. O consumo de água foi medido em dois lisímetros de pesagem instalados no interior da estufa. O espaçamento da cultura foi de 0,25 m x 0,25 m. Também foi avaliado o índice de área foliar (IAF em seis épocas distintas e determinada a eficiência do uso de água (EU ao final do ciclo da cultura. O delineamento estatístico foi o de blocos inteiramente casualizados, com dois tratamentos, "solo descoberto" e "solo coberto". O consumo médio de água foi de 4,17 mm dia-1 para o tratamento "solo descoberto" e de 3,11 mm dia-1 para o tratamento "solo coberto". O índice médio de área foliar não diferiu estatisticamente entre os tratamentos.The covering of the soil is an agricultural practice that intends to control the harmful herbs, to reduce the losses of water by evaporation of the soil, and to facilitate the harvest and the commercialization, once the product is cleaner and healthier. However, when the soil is covered important microclimatic parameters are also altered, and consequently the germination of seeds, the growth of roots, the absorption of water and nutrients, the metabolic activity of the plants and

  5. Gifsla (Lactuca virosa L.) en kompassla (Lactuca serriola L.) in Nederland

    NARCIS (Netherlands)

    Ham, van der R.W.J.M.

    1981-01-01

    Induced by too many wrongly determined specimens of Lactuca virosa L. the author discusses a number of differences with Lactuca serriola L. The fruit especially offers reliable characters (fig. 3). L. virosa probably occurs only as an alien in the Netherlands. In recent years L. serriola had a

  6. Consórcios alface-cenoura e alface-rabanete sob manejo orgânico.

    OpenAIRE

    SALGADO, A.S.; GUERRA, J.G.M.; ALMEIDA, D.L. de; RIBEIRO, R. de L.D.; ESPINDOLA, J.A.A.; SALGADO, J.A. de A.

    2006-01-01

    Dois experimentos foram conduzidos, por dois anos consecutivos, em Seropédica, RJ, com o objetivo de avaliar o desempenho agronômico dos consórcios das cultivares de alface 'Regina 71' (lisa) e 'Verônica' (crespa) com cenoura 'Brasília' e rabanete 'Híbrido nº 19', sob manejo orgânico, assim como determinar as quantidades de macronutrientes exportadas. O delineamento experimental usado foi o de blocos ao acaso, com quatro repetições. No primeiro experimento, os tratamentos consistiram de alfac...

  7. Oryza sativa

    Indian Academy of Sciences (India)

    2014-04-25

    Apr 25, 2014 ... [Wang L. and Zhang H. 2014 Genomewide survey and characterization of metacaspase gene family in rice (Oryza sativa). J. Genet. 93, 93–102]. Introduction. Programmed cell death ..... Arabidopsis, both proline and glutamine were found to be enriched in predicted N-terminal prodomain (Vercammen et al.

  8. Involvement of S-nitrosothiols modulation by S-nitrosoglutathione reductase in defence responses of lettuce and wild Lactuca spp. to biotrophic mildews.

    Science.gov (United States)

    Tichá, Tereza; Sedlářová, Michaela; Činčalová, Lucie; Trojanová, Zuzana Drábková; Mieslerová, Barbora; Lebeda, Aleš; Luhová, Lenka; Petřivalský, Marek

    2018-02-07

    Resistant Lactuca spp. genotypes can efficiently modulate levels of S-nitrosothiols as reactive nitrogen species derived from nitric oxide in their defence mechanism against invading biotrophic pathogens including lettuce downy mildew. S-Nitrosylation belongs to principal signalling pathways of nitric oxide in plant development and stress responses. Protein S-nitrosylation is regulated by S-nitrosoglutathione reductase (GSNOR) as a key catabolic enzyme of S-nitrosoglutathione (GSNO), the major intracellular S-nitrosothiol. GSNOR expression, level and activity were studied in leaves of selected genotypes of lettuce (Lactuca sativa) and wild Lactuca spp. during interactions with biotrophic mildews, Bremia lactucae (lettuce downy mildew), Golovinomyces cichoracearum (lettuce powdery mildew) and non-pathogen Pseudoidium neolycopersici (tomato powdery mildew) during 168 h post inoculation (hpi). GSNOR expression was increased in all genotypes both in the early phase at 6 hpi and later phase at 72 hpi, with a high increase observed in L. sativa UCDM2 responses to all three pathogens. GSNOR protein also showed two-phase increase, with highest changes in L. virosa-B. lactucae and L. sativa cv. UCDM2-G. cichoracearum pathosystems, whereas P. neolycopersici induced GSNOR protein at 72 hpi in all genotypes. Similarly, a general pattern of modulated GSNOR activities in response to biotrophic mildews involves a two-phase increase at 6 and 72 hpi. Lettuce downy mildew infection caused GSNOR activity slightly increased only in resistant L. saligna and L. virosa genotypes; however, all genotypes showed increased GSNOR activity both at 6 and 72 hpi by lettuce powdery mildew. We observed GSNOR-mediated decrease of S-nitrosothiols as a general feature of Lactuca spp. response to mildew infection, which was also confirmed by immunohistochemical detection of GSNOR and GSNO in infected plant tissues. Our results demonstrate that GSNOR is differentially modulated in interactions of

  9. Produção de sementes de alface em cultivo hidropônico

    Directory of Open Access Journals (Sweden)

    Menezes Nilson Lemos de

    2001-01-01

    Full Text Available Sementes de alface das cultivares Deyse e Regina foram produzidas em estufa, no sistema hidropônico, com elevados rendimentos por planta e boa qualidade de sementes, quando comparados a resultados de sistema convencional, de canteiros em campo. Esses dados sugerem estudos de produção de sementes de alface em cultivo protegido.

  10. Produção de sementes de alface em cultivo hidropônico

    OpenAIRE

    Menezes,Nilson Lemos de; Santos,Osmar Souza dos; Schmidt,Denise

    2001-01-01

    Sementes de alface das cultivares Deyse e Regina foram produzidas em estufa, no sistema hidropônico, com elevados rendimentos por planta e boa qualidade de sementes, quando comparados a resultados de sistema convencional, de canteiros em campo. Esses dados sugerem estudos de produção de sementes de alface em cultivo protegido.

  11. Energy production from marine biomass (Ulva lactuca)

    Energy Technology Data Exchange (ETDEWEB)

    Nikolaisen, L.; Daugbjerg Jensen, P.; Svane Bech, K. [Danish Technological Institute (DTI), Taastrup (Denmark)] [and others

    2011-11-15

    In this project, methods for producing liquid, gaseous and solid biofuel from the marine macroalgae Ulva lactuca has been studied. To get an understanding of the growth conditions of Ulva lactuca, laboratory scale growth experiments describing N, P, and CO{sub 2} uptake and possible N{sub 2}O and CH{sub 4} production are carried out. The macroalgae have been converted to bioethanol and methane (biogas) in laboratory processes. Further the potential of using the algae as a solid combustible biofuel is studied. Harvest and conditioning procedures are described together with the potential of integrating macroalgae production at a power plant. The overall conclusions are: 1. Annual yield of Ulva lactuca is 4-5 times land-based energy crops. 2. Potential for increased growth rate when bubbling with flue gas is up to 20%. 3. Ethanol/butanol can be produced from pretreated Ulva of C6 and - for butanol - also C5 sugars. Fermentation inhibitors can possibly be removed by mechanical pressing. The ethanol production is 0,14 gram pr gram dry Ulva lactuca. The butanol production is lower. 4. Methane yields of Ulva are at a level between cow manure and energy crops. 5. Fast pyrolysis produces algae oil which contains 78 % of the energy content of the biomass. 6. Catalytic supercritical water gasification of Ulva lactuca is feasible and a methane rich gas can be obtained. 7. Thermal conversion of Ulva is possible with special equipment as low temperature gasification and grate firing. 8. Co-firing of Ulva with coal in power plants is limited due to high ash content. 9. Production of Ulva only for energy purposes at power plants is too costly. 10. N{sub 2}O emission has been observed in lab scale, but not in pilot scale production. 11. Analyses of ash from Ulva lactuca indicates it as a source for high value fertilizers. 12. Co-digestion of Ulva lactuca together with cattle manure did not alter the overall fertilization value of the digested cattle manure alone. (LN)

  12. Metabolite profiling of sesquiterpene lactones from Lactuca species. Major latex components are novel oxalate and sulfate conjugates of lactucin and its derivatives.

    Science.gov (United States)

    Sessa, R A; Bennett, M H; Lewis, M J; Mansfield, J W; Beale, M H

    2000-09-01

    Wounding leaves or stems of Lactuca species releases a milky latex onto the plant surface. We have examined the constituents of latex from Lactuca sativa (lettuce) cv. Diana. The major components were shown to be novel 15-oxalyl and 8-sulfate conjugates of the guaianolide sesquiterpene lactones, lactucin, deoxylactucin, and lactucopicrin. The oxalates were unstable, reverting to the parent sesquiterpene lactone on hydrolysis. Oxalyl derivatives have been reported rarely from natural sources. The sulfates were stable and are the first reported sesquiterpene sulfates from plants. Unusual tannins based on 4-hydroxyphenylacetyl conjugates of glucose were also identified. Significant qualitative and quantitative variation was found in sesquiterpene lactone profiles in different lettuce varieties and in other Lactuca spp. The proportions of each conjugate in latex also changed depending on the stage of plant development. A similar profile was found in chicory, in which oxalyl conjugates were identified, but the 8-sulfate conjugates were notably absent. The presence of the constitutive sesquiterpene lactones was not correlated with resistance to pathogens but may have a significant bearing on the molecular basis of the bitter taste of lettuce and related species. The induced sesquiterpene lactone phytoalexin, lettucenin A, was found in the Lactuca spp. but not in chicory.

  13. Produção orgânica de alface e rabanete em cultivo solteiro e consorciado

    Directory of Open Access Journals (Sweden)

    Elton G. Rezende

    2014-06-01

    Full Text Available O presente estudo teve como objetivo avaliar a produção de alface e rabanete em cultivo solteiro e consorciado em sistema orgânico. O experimento foi realizado no campo experimental da UEMS, Glória de Dourados, MS, num solo classificado como Argissolo Vermelho, textura arenosa. O delineamento estatístico utilizado no experimento foi de blocos casualizados, com três repetições. Os tratamentos foram constituídos por três cultivares de alface consorciadas com uma de rabanete: 1 Alface americana em monocultivo, 2 Alface crespa em monocultivo, 3 Alface roxa em monocultivo, 4 Rabanete em monocultivo, 5 Alface americana consorciada com rabanete, 6 Alface crespa consorciada com rabanete e 7 Alface roxa consorciada com rabanete. Nas condições em que foi executado este experimento, pode-se concluir que o cultivo consorciado de alface com rabanete foi adequado do ponto de vista agronômico, pois a presença do rabanete não prejudicou a produção de alface, além de se apresentar como possibilidade concreta de gerar renda extra para o agricultor em uma mesma área física.

  14. Quality of minimally processed crisp head lettuce packaged under modified atmosphere

    OpenAIRE

    Roversi, Rosana Mendes; Masson, Maria Lucia

    2004-01-01

    A alface Crespa (Lactuca sativa L.)foi minimamente processada, tendo suas folhas destacadas e higienizadas, embalada em sacos plásticos de polietileno com modificação ativa da atmosfera dentro do pacote. Duas atmosferas foram aplicadas, variando-se o nível de CO2 em 10 e 15%, reduzindo nos dois casos o O2 a 5%. Após o acondicionamento, a alface foi imediatamente refrigerada. Comparou-se a qualidade da alface com e sem atmosfera modificada durante o armazenamento refrigerado. Monitoraram-se a ...

  15. Cannabis sativa

    Science.gov (United States)

    Yang, Yi; Lewis, Melissa M; Bello, Angelica M; Wasilewski, Ewa; Clarke, Hance A; Kotra, Lakshmi P

    2017-01-01

    Introduction: Cannabis sativa (hemp) seeds are popular for their high nutrient content, and strict regulations are in place to limit the amount of potentially harmful phytocannabinoids, especially Δ 9 -tetrahydrocannabinol (Δ 9 -THC). In Canada, this limit is 10 μg of Δ 9 -THC per gram of hemp seeds (10 ppm), and other jurisdictions in the world follow similar guidelines. Materials and Methods: We investigated three different brands of consumer-grade hemp seeds using four different procedures to extract phytocannabinoids, and quantified total Δ 9 -THC and cannabidiol (CBD). Discussion: We discovered that Δ 9 -THC concentrations in these hemp seeds could be as high as 1250% of the legal limit, and the amount of phytocannabinoids depended on the extraction procedure employed, Soxhlet extraction being the most efficient across all three brands of seeds. Δ 9 -THC and CBD exhibited significant variations in their estimated concentrations even from the same brand, reflecting the inhomogeneous nature of seeds and variability due to the extraction method, but almost in all cases, Δ 9 -THC concentrations were higher than the legal limit. These quantities of total Δ 9 -THC may reach as high as 3.8 mg per gram of hemp seeds, if one were consuming a 30-g daily recommended amount of hemp seeds, and is a cause for concern for potential toxicity. It is not clear if these high quantities of Δ 9 -THC are due to contamination of the seeds, or any other reason. Conclusion: Careful consideration of the extraction method is very important for the measurement of cannabinoids in hemp seeds.

  16. Crescimento e produção de alface e marcela em cultivo solteiro e consorciado

    OpenAIRE

    Mota,José Hortêncio; Vieira,Maria do Carmo; Araújo,Charles de

    2011-01-01

    Este estudo teve por objetivo avaliar a produtividade e a renda bruta da alface e marcela em cultivo solteiro e consorciado. O experimento foi realizado com duas fileiras de marcela espaçadas de 0,50 m; duas fileiras de marcela espaçadas de 0,35 m; três fileiras de alface espaçadas em 0,35 m; quatro fileiras de alface espaçadas em 0,25 m; duas fileiras de marcela espaçadas de 0,50 m alternadas com quatro fileiras de alface; e duas fileiras de marcela espaçadas de 0,35 m alternadas com três fi...

  17. Nutritional value of green seaweed (Ulva lactuca for broiler chickens

    Directory of Open Access Journals (Sweden)

    Alaeldein M. Abudabos

    2013-04-01

    Full Text Available The current work aimed to assess the potential of the green seaweed Ulva lactuca (U. lactuca as an alternative ingredient in broiler chicken diets. The effect of substituting 1.0 or 3.0% of corn with U. lactuca on performance, carcass characteristics, serum constituents and nutrients retention of broilers from 12 to 33 d of age was evaluated. Three treatments were distributed in a RCBD design: T1 = control diet (0% U. lactuca; T2 = 1.0 % U. lactuca; T3 = 3.0 % U. lactuca. Cumulative feed intake (FI, body weight gain (BWG, feed conversion ratio (FCR and nutrients retention from 12 to 33 d of age were not affected by treatment (P>0.05. Birds which had received T3 had a higher dressing percentage and breast muscle yield compared to those which had received T1 or T2. Serum total lipid, cholesterol and uric acid concentrations were significantly lower in birds which had received T2 and T3 (P<0.05. Serum enzymes and electrolytes were not influenced by any dietary treatment except for alanine transaminase (ALT which was significantly lower for the treated groups. Based on presented evidences, it is recommended to substitute 3.0% of corn with green seaweed (U. lactuca.

  18. PESQUISA DE PARASITOS EM ALFACE E COUVE PROVENIENTES DE FEIRAS DA REGIÃO CENTRAL E SUAS MEDIAÇÕES NA CIDADE DE ANÁPOLIS-GO

    Directory of Open Access Journals (Sweden)

    Léa Resende Moura

    2015-12-01

    Full Text Available Objective: To evaluate the parasitological quality of vegetables lettuce (Lactuca sativa and cabbage (Brassica oleracea marketed by 28 stalls divided into four exhibitions located in central and mediations in the city of Anápolis-GO. Methods: A total of 28 samples of lettuce and 28 samples of cabbage by spontaneous sedimentation techniques and Craig. Results: We obtained 16% contamination by intestinal parasites in 56 samples. Lettuce showed greater contamination (25% and cabbage showed contamination of 7.1%. The enteroparasite more prevalent among the lettuce was Entamoeba coli (17.8%; on cabbage samples, as well as Entamoeba coli (3.5%, we found Ascaris lumbricoides (3.5%. Conclusions: Probably the presence of these enteroparasito can be related to a low hygienic standard in some management steps of greenery. There is a clear need to increase health education of vegetable handlers and improving the quality of water used in these vegetable crops processes.

  19. Promoção do crescimento de alface por rizobactérias

    OpenAIRE

    Freitas,S. S.; Melo,A. M. T.; Donzeli,V. P.

    2003-01-01

    Rizobactérias promotoras do crescimento de plantas (RPCPs) podem ser uma alternativa para o aumento da produtividade de várias espécies vegetais, inclusive alface. Conduziram-se quatro experimentos com isolados de rizobactérias de diversas origens para verificar sua capacidade de promoção de crescimento de plantas de alface. Ao todo, testaram-se 77 isolados de Pseudomonas do grupo fluorescente, 23 de Bacillus e 11 de outras bactérias rizosféricas em areia esterilizada, em solo esterilizado, e...

  20. Efeito da urina de vaca no estado nutricional da alface

    Directory of Open Access Journals (Sweden)

    Nelson Licínio C. de Oliveira

    2010-08-01

    Full Text Available Existem diversos relatos da utilização da urina de vaca em hortaliças, todavia sua eficácia carece de comprovação. Objetivou-se avaliar o efeito da urina de vaca no estado nutricional da alface. O experimento foi constituído de 12 tratamentos, esquema de parcelas subdivididas, em blocos ao acaso, com quatro repetições. Nas parcelas foram alocadas as vias de aplicação (solo ou foliar e nas subparcelas as concentrações das soluções (0,00; 0,25; 0,50; 0,75; 1,00 e 1,25% v/v. Aplicou-se 60 mL de solução/planta, divididos em cinco aplicações de 5; 5; 10; 20 e 20 mL/planta, aos 7, 14, 21, 28 e 35 após o transplante, respectivamente. Durante o ciclo avaliou-se o índice SPAD e na colheita a massa da matéria seca de cabeça (MSCA e os teores de N, P, K, Ca, Mg, S, Na, Zn, Fe, Mn, Cu e B na matéria seca das folhas (MSF, caule (MSC e raízes (MSR. Em ambas as vias de aplicação o índice SPAD apresentou incremento linear às concentrações e resposta quadrática ao longo do tempo. A MSCA teve comportamento linear às concentrações, com aumento de 25,9 e 35,4% nas aplicações via foliar e solo, respectivamente. Não houve efeito de concentrações sobre teores de nutrientes na MSF e MSC. Na MSR, via solo, os teores de P e K apresentaram pontos de máximo enquanto Fe e Mn de mínimo; o Na apresentou incremento linear às concentrações via foliar. Os efeitos da urina sobre o crescimento da alface provavelmente são devidos a fatores outros que não somente a quantidade de nutrientes veiculados nas soluções.

  1. Produção orgânica de alface e rabanete em cultivo solteiro e consorciado

    OpenAIRE

    Elton G. Rezende; Michele da Silva Gomes; Patricia R. Agostinho; Rogério de M. Xavier; Rogério F. da Silva

    2014-01-01

    O presente estudo teve como objetivo avaliar a produção de alface e rabanete em cultivo solteiro e consorciado em sistema orgânico. O experimento foi realizado no campo experimental da UEMS, Glória de Dourados, MS, num solo classificado como Argissolo Vermelho, textura arenosa. O delineamento estatístico utilizado no experimento foi de blocos casualizados, com três repetições. Os tratamentos foram constituídos por três cultivares de alface consorciadas com uma de rabanete: 1) Alface americana...

  2. PRODUÇÃO DE ALFACE HIDROPÔNICA E MICROCLIMA DE AMBIENTE PROTEGIDO SOB MALHAS TERMO-REFLETORAS

    Directory of Open Access Journals (Sweden)

    OSVALDO NOGUEIRA DE SOUSA NETO

    2010-01-01

    Full Text Available The thermo-reflective and black screens was used for shading for plants and they has private properties that improve the microclimate conditions, it was aimed to evaluate the growth and yields in hydroponic lettuce production (Lactuca sativa L, cv. Olinda, under effect of the thermo-reflective with different percentages of attenuation of the solar radiation. The treatments were and thermo black screens 50% with four different percentages of attenuation of the solar radiation, being meshes 40, 50, 60 and 70%. It was observed significant differences in function of the treatments for all the analyzed characteristics number of leaf, diameter of stem, fresh and dry matter biomass, leaf area and distances of internodes. The meshes thermo-reflective 40 and 50%, it had provided better development for lettuce, in relation to expression of the economical characteristics, being suitable to supply shading in greenhouse conditions at Northeastern semi-arid areas. However, it's improved the most control of the solar radiation, temperature and relative humidity, with micro weather conditions the best for growth and yields of Lettuce.

  3. MADS-box genes and gibberellins regulate bolting in lettuce (Lactuca sativa L.

    Directory of Open Access Journals (Sweden)

    Yingyan Han

    2016-12-01

    Full Text Available Bolting in lettuce is promoted by high temperature and bolting resistance is of great economic importance for lettuce production. But how bolting is regulated at the molecular level remains elusive. Here, a bolting resistant line S24 and a bolting sensitive line S39 were selected for morphological, physiological, transcriptomic and proteomic comparisons. A total of 12204 genes were differentially expressed in S39 vs S24. Line S39 was featured with larger leaves, higher levels of chlorophyll, soluble sugar, anthocyanin and auxin, consistent with its up-regulation of genes implicated in photosynthesis, oxidation-reduction and auxin actions. Proteomic analysis identified 30 differentially accumulated proteins in lines S39 and S24 upon heat treatment, and 19 out of the 30 genes showed differential expression in the RNA-Seq data. Exogenous gibberellins (GA treatment promoted bolting in both S39 and S24, while 12 flowering promoting MADS-box genes were specifically induced in line S39, suggesting that although GA regulates bolting in lettuce, it may be the MADS-box genes, not GA, that plays a major role in differing the bolting resistance between these two lettuce lines.

  4. MADS-Box Genes and Gibberellins Regulate Bolting in Lettuce (Lactuca sativaL.).

    Science.gov (United States)

    Han, Yingyan; Chen, Zijing; Lv, Shanshan; Ning, Kang; Ji, Xueliang; Liu, Xueying; Wang, Qian; Liu, Renyi; Fan, Shuangxi; Zhang, Xiaolan

    2016-01-01

    Bolting in lettuce is promoted by high temperature and bolting resistance is of great economic importance for lettuce production. But how bolting is regulated at the molecular level remains elusive. Here, a bolting resistant line S24 and a bolting sensitive line S39 were selected for morphological, physiological, transcriptomic and proteomic comparisons. A total of 12204 genes were differentially expressed in S39 vs. S24. Line S39 was featured with larger leaves, higher levels of chlorophyll, soluble sugar, anthocyanin and auxin, consistent with its up-regulation of genes implicated in photosynthesis, oxidation-reduction and auxin actions. Proteomic analysis identified 30 differentially accumulated proteins in lines S39 and S24 upon heat treatment, and 19 out of the 30 genes showed differential expression in the RNA-Seq data. Exogenous gibberellins (GA) treatment promoted bolting in both S39 and S24, while 12 flowering promoting MADS-box genes were specifically induced in line S39, suggesting that although GA regulates bolting in lettuce, it may be the MADS-box genes, not GA, that plays a major role in differing the bolting resistance between these two lettuce lines.

  5. Absorcion de nutrientes en cuatro materiales de lechuga, Lactuca sativa L.

    Directory of Open Access Journals (Sweden)

    Archila Julio Agapito

    1997-06-01

    Full Text Available

    En el Centro Nacional de Investigaciones Agropecuarias, ICA, Tibaitata, en el municipio de Mosquera (Cundinamarca, en el aña de 1991, se realizo un estudio de campo con cuatro materiales de lechuga procedentes de semillas importadas y nacionales producidas en condiciones de la Sabana de Bogotá, de las variedades Great Lakes 118 y Climax . En el estudio se utilizo un diseño experimental de bloques al azar con tres replicaciones y cuatro tratamientos (origen de la semilla. Se toma información sobre los contenidos de oligoelementos y microelementos a intervalos de ocho días después del transplante y hasta la cosecha. En el ultimo muestreo (cosecha final, se les realizo un análisis bromatológico a los cuatro materiales de lechuga con el fin de comparar su valor nutritivo. Los resultados obtenidos no presentaron diferencias estadísticas entre los cuatro materiales de lechuga en lo pertinente a contenido de nutrientes y calidad de los productos. También, se encontró que el promedio de la producción fue de 22 toneladas de lechuga, con 90% de humedad y el cultivo extrajo 60,5 Kg. de nitrógeno, 48,4 Kg de fosforo y 136,4 Kg de potasio.

    Palabras Claves: Nutrición, bromatología.

  6. Transfer of heavy metals from soil to lettuce (Lactuca sativa) grown ...

    African Journals Online (AJOL)

    This studied was carried out to investigate the amount of heavy metals (Fe, Cd, Zn,Cu and Pd) transferred from soil to lettuce so as to know the extent of contamination from Soil and lettuce samples collected from different irrigated farmlands of Kaduna metropolis and Rigachikun as control site. These heavy metals were ...

  7. Human granulocyte colony-stimulating factor (hG-CSF) expression in plastids of Lactuca sativa.

    Science.gov (United States)

    Sharifi Tabar, Mehdi; Habashi, Ali Akbar; Rajabi Memari, Hamid

    2013-01-01

    Human granulocyte colony-stimulating factor (hG-CSF) can serve as valuable biopharmaceutical for research and treatment of the human blood cancer. Transplastomic plants have been emerged as a new and high potential candidate for production of recombinant biopharmaceutical proteins in comparison with transgenic plants due to extremely high level expression, biosafety and many other advantages. hG-CSF gene was cloned into pCL vector between prrn16S promoter and TpsbA terminator. The recombinant vector was coated on nanogold particles and transformed to lettuce chloroplasts through biolistic method. Callogenesis and regeneration of cotyledonary explants were obtained by Murashige and Skoog media containing 6-benzylaminopurine and 1-naphthaleneacetic acid hormones. The presence of hG-CSF gene in plastome was studied with four specific PCR primers and expression by Western immunoblotting. hG-CSF gene cloning was confirmed by digestion and sequencing. Transplastomic lettuce lines were regenerated and subjected to molecular analysis. The presence of hG-CSF in plastome was confirmed by PCR using specific primers designed from the plastid genome. Western immunoblotting of extracted protein from transplastomic plants showed a 20-kDa band, which verified the expression of recombinant protein in lettuce chloroplasts. This study is the first report that successfully express hG-CSF gene in lettuce chloroplast. The lettuce plastome can provide a cheap and safe expression platform for producing valuable biopharmaceuticals for research and treatment.

  8. Methodological aspects of the complex evaluation of biological potential of the Sown Lettuce (Lactuca sativa L.

    Directory of Open Access Journals (Sweden)

    Н. В. Лещук

    2008-04-01

    Full Text Available State of national recourses of Sown Lettuce is considered, as well as way of their formation. Methodological aspects of biological potential utilization of Sawn Salad (leaf, head, Rome, stem are displayed to widen their assortment. Dependence of marginal potentially possible yield of the Sown Lettuce varieties on influence of the environmental causes has been established.

  9. Physiological and molecular response of Lactuca sativa to colonization by Salmonella enterica serovar Dublin

    NARCIS (Netherlands)

    Klerks, M.M.; Gent-Pelzer, van M.P.E.; Franz, E.; Zijlstra, C.; Bruggen, van A.H.C.

    2007-01-01

    This paper describes the physiological and molecular interactions between the human-pathogenic organism Salmonella enterica serovar Dublin and the commercially available mini Roman lettuce cv. Tamburo. The association of S. enterica serovar Dublin with lettuce plants was first determined, which

  10. Effect of Salt Stress on Morphological Traits of Lettuce Genotypes (Lactuca Sativa L.

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    maryam zare

    2017-02-01

    Full Text Available Introduction: The recognition of salt tolerant plants is important as a result ofincreasing saline lands in Iran and world. Cultivation of plants in hydroponic environment is a reliable and economical method in order to select the salt tolerant plant. Salt stress can effect on plant growth and development by ion toxicity, ionic disturb the balance and osmotic potential. Lettuce is one of the most important vegetable crops. This plant is one of the most important leafy vegetables which is used for salad and fresh marketing, also some types of this vegetable is used in baked type. The aim of this study was to investigate the genetic diversity of lettuce genotypes undersalt stress in the hydroponic system. Materials and Methods: To assess response of lettuce seedlings to salt stress, a factorial experiment was conducted in a completely randomized design with three replications at Biotechnology Research Institute for hydroponic cultivation of Zabol. In this experiment, the effects of three salinity levels (0, 2 and 4 dS/m on morphological characteristics of 15 lettuce genotypes were evaluated. The seeds were sterilized for ten seconds in ethanol 96% and then 15% sodium hypochlorite solution for 50 seconds, then rinsed several times with distilled water, then disinfected seeds were cultured in plastic pots containing coco peat and perlite. After …days plants were transferred to hydroponic system containing Hoagland solution. Collected data were analyzed and means comparisons were made using LSD by SAS software. Results and Discussion: The results showed that salinity has a significant effect on seedling growth of lettuce genotypes (p≤0.01. significant difference between salinity levels and genotype were observed for all traits. Interaction of genotype and salinity for all the traits except root length, plant length and leaf were significant at 1%. Based on the results, the greatest root length was belong to Esfahan Varzaneh leafy lettuce and Romaine lettuce long green Teresa genotype, respectivly. Increasing salinity led to significant reduction (p≤0.01 in the plant length lettuce in all genotypes. Root and plant fresh weight lettuce genotypes were significantly (p≤0.01 influenced by different levels of salinity. The greatest amount in root and plant fresh weight lettuce genotypes were obtained in the control treatment and the lowest amount at the level of 4 dS/m. Root and plant dry weight lettuce genotypes were significantly (p≤0.01 influenced by the salinity. Root and plant dry weight decreased with increasing salinity. So that the greatest amount of root and plant dry weight lettuce genotypes were obtained in control treatment and the lowest amount at the level of 4 dS/m.. The results showed that root and plant length ,root fresh and dry weight, plant fresh and dry weight and leaf length and width reduced with increasing salinity. The clustering pattern the genotypes were grouped into 3 clusters based on their charachters at 4 dS/m salinity. The first cluster were placed in salt tolerant groups, while the other genotypes were clustered into moderately tolerant cluster. Romaine lettuce long green Teresa genotype was placed in salt-tolerant group and Lettuce Everest, Lettuce May Queen, Curly endive hair angel, Cabbage Milan Aubervilliers and Romaine lettuce long blonde Galaica were placed in salt-sensitive group.

  11. Foliar fertilizations with boron and growth regulators on lettuce (Lactuca sativa L.) cv floresta culture

    International Nuclear Information System (INIS)

    Masunaga, S.I.; Chueire, F.B.; Teixeira, N.T.

    1989-01-01

    The experiment was realized to verify the possibility of applying Boron as foliar fertilization with growth regulators: indol acetic acid, giberellic acid, ethephon and cycocel. The other objective was to compare the foliar and soil fertilization, with Boron, on the lettuce culture. The results showed that there wasn't difference of production between the treatments. Meanwhile the application of growth regulator modified the Boron grade in the leaves. (author) [pt

  12. Ultrastructural and developmental evidence of phytotoxicity on cos lettuce (Lactuca sativa) associated with nonylphenol exposure.

    Science.gov (United States)

    de Bruin, Willeke; van der Merwe, Chris; Kritzinger, Quenton; Bornman, Riana; Korsten, Lise

    2017-02-01

    It has long been understood that the presence of endocrine disrupter chemicals (EDCs) in water can affect the reproductive, behavioural and regulatory systems of different types of mammals. Thus far, only a handful of studies have examined its impact on plant systems. Present research is limited to the potential uptake of these chemicals by plants and the general phytotoxic effects it can elicit. The aim of this study was to determine what effect an EDC has on developing plant and cell organelles and how it affects it. In this study, cos lettuce plants were exposed to different concentrations of nonylphenol (NP), an EDC, in a static hydroponic system. Changes in plant morphology, mass and length, chlorophyll content, as well as electrolyte leakage were examined. Furthermore an in-depth investigation of the plant cell ultrastructure was carried out with transmission electron microscopy. Results indicated that cos lettuce growth was severely restricted, chlorophyll content was reduced, leakage of electrolytes increased and roots were stunted especially after ≥3200 μg/l NP exposures. The structure of the rough endoplasmic reticulum, vacuole and chloroplast were also changed. This study emphasizes the importance of water quality management, since the presence of an EDC, like NP, can negatively impact the yield and internal structure of one of the world's most significant salad crops, namely lettuce. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Dose-dependent effects of gamma radiation on lettuce (Lactuca sativa var. capitata) seedlings.

    Science.gov (United States)

    Marcu, Delia; Cristea, Victoria; Daraban, Liviu

    2013-03-01

    Abstract Purpose: The objectives of this study were to determine the effects of gamma radiation on lettuce growth and development, as well as on the content of photosynthetic pigments in 28 days lettuce leaf. Lettuce dry seeds were exposed to a (60)Co [Cobalt-60] gamma source at doses ranging from 2-70 Gray (Gy). The photosynthetic pigment content was determined spectrophotometrically. Our results showed that an irradiation dose between of 2-30 Gy enhanced the growth parameters (final germination percentage, germination index, root and hypocotyl length) as compared to untreated plants. Seed germination test revealed that 30 Gy irradiation dose induced the highest increase of growth parameters, while at 70 Gy a significant decrease of plant vegetative growth was recorded. The results indicated that exposing the seeds at doses ranging from 2-30 Gy enhanced the photosynthetic pigments (chlorophyll a, chlorophyll b, carotenoids) content, while at higher doses (70 Gy)) the decrease of the assimilatory pigments was noticed. The present results suggested that seed treatment with gamma radiations (0-30 Gy) was effective in stimulating plant growth and development, as well as the content of assimilatory pigments. At a higher dose of 70 Gy, there was a drastic reduction in the length of shoots and roots and also in the total chlorophyll content. These observations confirm that ionizing radiation stimulates physiological parameters up to certain low doses, and then it inhibits these parameters at higher doses.

  14. Cadmium uptake in above-ground parts of lettuce (Lactuca sativa L.).

    Science.gov (United States)

    Tang, Xiwang; Pang, Yan; Ji, Puhui; Gao, Pengcheng; Nguyen, Thanh Hung; Tong, Yan'an

    2016-03-01

    Because of its high Cd uptake and translocation, lettuce is often used in Cd contamination studies. However, there is a lack of information on Cd accumulation in the above-ground parts of lettuce during the entire growing season. In this study, a field experiment was carried out in a Cd-contaminated area. Above-ground lettuce parts were sampled, and the Cd content was measured using a flame atomic absorption spectrophotometer (AAS). The results showed that the Cd concentration in the above-ground parts of lettuce increased from 2.70 to 3.62mgkg(-1) during the seedling stage, but decreased from 3.62 to 2.40mgkg(-1) during organogenesis and from 2.40 to 1.64mgkg(-1) during bolting. The mean Cd concentration during the seedling stage was significantly higher than that during organogenesis (a=0.05) and bolting (a=0.01). The Cd accumulation in the above-ground parts of an individual lettuce plant could be described by a sigmoidal curve. Cadmium uptake during organogenesis was highest (80% of the total), whereas that during bolting was only 4.34%. This research further reveals that for Rome lettuce: (1) the highest Cd content of above-ground parts occurred at the end of the seedling phase; (2) the best harvest time with respect to Cd phytoaccumulation is at the end of the organogenesis stage; and (3) the organogenesis stage is the most suitable time to enhance phytoaccumulation efficiency by adjusting the root:shoot ratio. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Lettuce (Lactuca sativa L. var. Sucrine) growth performance in complemented aquaponic solution outperforms hydroponics

    OpenAIRE

    Delaide, Boris; Goddek, Simon; Gott, James; Soyeurt, Hélène; Jijakli, M.H.

    2016-01-01

    Plant growth performance is optimized under hydroponic conditions. The comparison between aquaponics and hydroponics has attracted considerable attention recently, particularly regarding plant yield. However, previous research has not focused on the potential of using aquaponic solution complemented with mineral elements to commercial hydroponic levels in order to increase yield. For this purpose, lettuce plants were put into AeroFlo installations and exposed to hydroponic (HP), aquaponic (AP...

  16. Lettuce (Lactuca sativa L. var. Sucrine Growth Performance in Complemented Aquaponic Solution Outperforms Hydroponics

    Directory of Open Access Journals (Sweden)

    Boris Delaide

    2016-10-01

    Full Text Available Plant growth performance is optimized under hydroponic conditions. The comparison between aquaponics and hydroponics has attracted considerable attention recently, particularly regarding plant yield. However, previous research has not focused on the potential of using aquaponic solution complemented with mineral elements to commercial hydroponic levels in order to increase yield. For this purpose, lettuce plants were put into AeroFlo installations and exposed to hydroponic (HP, aquaponic (AP, or complemented aquaponic (CAP solutions. The principal finding of this research was that AP and HP treatments exhibited similar (p > 0.05 plant growth, whereas the shoot weight of the CAP treatment showed a significant (p < 0.05 growth rate increase of 39% on average compared to the HP and AP treatments. Additionally, the root weight was similar (p > 0.05 in AP and CAP treatments, and both were significantly higher (p < 0.05 than that observed in the HP treatment. The results highlight the beneficial effect of recirculating aquaculture system (RAS water on plant growth. The findings represent a further step toward developing decoupled aquaponic systems (i.e., two- or multi-loops that have the potential to establish a more productive alternative to hydroponic systems. Microorganisms and dissolved organic matter are suspected to play an important role in RAS water for promoting plant roots and shoots growth.

  17. Lettuce (Lactuca sativa L. var. Sucrine) growth performance in complemented aquaponic solution outperforms hydroponics

    NARCIS (Netherlands)

    Delaide, Boris; Goddek, Simon; Gott, James; Soyeurt, Hélène; Jijakli, M.H.

    2016-01-01

    Plant growth performance is optimized under hydroponic conditions. The comparison between aquaponics and hydroponics has attracted considerable attention recently, particularly regarding plant yield. However, previous research has not focused on the potential of using aquaponic solution

  18. Diversité et dynamique des Salmonella Lactuca sativa L.) dans les ...

    African Journals Online (AJOL)

    Objectif: Au Niger, l'agriculture maraîchère réalisée dans les zones urbaines et péri-urbaines utilise les eaux usées souvent très souillées par la matière fécale humaine et animale pour l'irrigation. Cette étude a évalué la prévalence et la diversité des Salmonella isolées de la laitue dans différents sites maraichers du Niger.

  19. Quantitative detection of Salmonella enterica and the specific interaction with Lactuca sativa

    NARCIS (Netherlands)

    Klerks, M.M.

    2007-01-01

    Salmonella is among the most commonly known bacterial pathogens to cause human illness. Often Salmonellosis is associated with the consumption of contaminated foods like meat, eggs or egg products. However, during the last decades an increase of outbreaks is recognized to be caused by human

  20. Effects of environmental factors on the morphometric characteristics of cultivated lettuce (Lactuca sativa L.

    Directory of Open Access Journals (Sweden)

    Antonio D Ojeda

    2012-09-01

    Full Text Available We evaluated the phenotypic response of three varieties of lettuce Batavia Colwart, Lisa Elisa and Crespa Verde Cassabella in three growing environments: plastic greenhouse, glass greenhouse and open field on the Bogota Plateau (Chia, Cundinamarca, in order to generate useful information to improve the quality of plants grown by farmers, ensuring a healthy product with characteristics that meet market demands. The three agroecosystems were constantly monitored for the environmental variables of temperature, relative humidity and solar radiation; which showed a significant variation between the three agroecosystems. To assess the phenotypic response, we examined the effect of the environmental variables mentioned on seven morphometric variables of agronomic interest. The study showed that, for the variables germination percentage and fresh weight, the environmental effect reached a variance percentage of 79 and 44%, respectively. On the contrary, it was established that the average phenotypic response of the variables clean weight and percentage of dry mass corresponds especially to the effect of genetic varieties with a variance percentage of 35 and 45%, respectively. Similarly, for the variables specific leaf area and total leaf area, it was established that both the effects of environmental and genetic variables explain 87% (50 genetic, 37 environmental and 56% (31 genetic, 25 environmental, respectively, of the total variability observed

  1. Use human urine as fertilizer in producing lettuce Waldmann green (Lactuca sativa L.

    Directory of Open Access Journals (Sweden)

    Mamani-Mamani Virginia

    2015-05-01

    Full Text Available The objective was to evaluate the response of growing lettuce, variety Waldmann Green, to the application of fermented human urine (HUF at different times. Urine was obtained from ecological toilets in the 7th district of El Alto municipal- ity. These exudates, fermentation took during different times: 3, 6 and 12 months, in order to eliminate the possible presence of pathogens. The treatments were T-1, with no urine, T-2, three months of fermentation, T-3 six months of fermentations and T-4 twelve months of fermentation. The highest value obtained was 14.75 cm plant height, which corresponds to T-3 treatment and the control (T-1 reached 17.71 cm, plant height. The T-3 applied with six months of obtained a performance of 5.52 kg m-2. This result could be due to the high concentration of nitrogen that has human urine and the witness presented a performance of 3.04 kg m-2. Likewise, we realize product compositional analysis to evaluate the presence of potential pathogens and according to the results did not present infestation of pathogens such as Escherichia coli and Salmonella spp. It is therefore suitable for human consumption without presenting health risk.

  2. Changes in the physico-chemical properties of four lettuce (Lactuca sativa L. varieties during storage

    Directory of Open Access Journals (Sweden)

    María Vargas-Arcila

    2017-05-01

    Full Text Available Lettuce, a popularly consumed leafy vegetable, is well known for its health and nutritional value. Thus, the current study focused on the qualitative changes of four lettuce varieties, namely Alpha, Parris Island, Graziella and Lollo Rossa, stored at 5.5 ºC and 90 % RH for 12 days. The analyzed parameters were water content, total soluble solids (TSS, titrable acidity (TA, vitamin C, total phenols, polyphenoloxidase (PPO, color and texture. Under storage conditions, the studied varieties exhibited different rates of water loss. TSS was found to increase until day 8 of storage, which is also when TA differences were observed. The Graziella variety showed the highest vitamin C levels. Total phenol content decreased significantly during the 12 days of storage. No significant PPO activity changes were found, except for those of the Lollo Rossa variety. Biplot analysis allowed observing not only positive and negative correlations between coordinates L*, a* and b*, but also the separavtion of the green lettuce varieties from the red one, together with color variations depending on leaf position. Although textural changes were recorded at the end of the study, foliage quality was not altered. In short, the studied parameters, which contribute to lettu-ce direct consumption properties, can be said to be variety-dependent and better preserved under refrigeration.

  3. Mode of Managing Nutrient Solution Based on N Use Efficiency for Lettuce (Lactuca sativa L.).

    Science.gov (United States)

    Chabite, Ibraimo Teleha; Lei, Zhang; Ningning, Yao; Qiang, Fu; Haiye, Yu

    2017-01-01

    In aeroponic cultivation the nutrient solution is an essential component to achieve good production results. And nitrogen is the main constituent element of the nutrient solution and essential element in plant nutrition. Therefore, the management and monitoring nutrient solution and existing nitrogen is fundamental. The experiment shows that three modes of replacing the nutrient solution and three initial pH values and their interaction significantly influenced the fresh weight and dry matter of lettuce. The highest values of fresh and dry weight were recorded in the fifth treatment where there is an interaction between pH 6 and the mode of replacing half of the nutrient solution. The consumption rate of nitrate nitrogen (NO 3 -N), ammonium nitrogen (NH 4 -N) and gross nitrogen (GN) was higher during stage 1 (10 days after transplanting), especially for the mode of complete replacing nutrient solution.

  4. Improving Water Use Efficiency of Lettuce (Lactuca sativa L.) Using Phosphorous Fertilizers.

    Science.gov (United States)

    Alkhader, Asad M F; Abu Rayyan, Azmi M

    2013-01-01

    A greenhouse pot experiment was conducted to evaluate the effect of phosphorous (P) fertilizers application to an alkaline calcareous soil on the water use efficiency (WUE) of lettuce cultivar "robinson" of iceberg type. Head fresh and dry weights, total water applied and WUE were affected significantly by the P fertilizer type and rate. P fertilizers addition induced a significant enhancement in the WUE and fresh and dry weights of the crop. A local phosphate rock (PR) applied directly was found to be inferior to the other types of P fertilizers (Mono ammonium phosphate (MAP), Single superphosphate (SSP), and Di ammonium phosphate ((DAP)). MAP fertilizer at 375 and 500 kg P2O5/ha application rates recorded the highest significant values of head fresh weight and WUE, respectively.

  5. Photoprotection vs. Photoinhibition of Photosystem II in Transplastomic Lettuce (Lactuca sativa) Dominantly Accumulating Astaxanthin.

    Science.gov (United States)

    Fujii, Ritsuko; Yamano, Nami; Hashimoto, Hideki; Misawa, Norihiko; Ifuku, Kentaro

    2016-07-01

    Transplastomic (chloroplast genome-modified; CGM) lettuce that dominantly accumulates astaxanthin grows similarly to a non-transgenic control with almost no accumulation of naturally occurring photosynthetic carotenoids. In this study, we evaluated the activity and assembly of PSII in CGM lettuce. The maximum quantum yield of PSII in CGM lettuce was <0.6; however, the quantum yield of PSII was comparable with that in control leaves under higher light intensity. CGM lettuce showed a lower ability to induce non-photochemical quenching (NPQ) than the control under various light intensities. The fraction of slowly recovering NPQ in CGM lettuce, which is considered to be photoinhibitory quenching (qI), was less than half that of the control. In fact, 1 O 2 generation was lower in CGM than in control leaves under high light intensity. CGM lettuce contained less PSII, accumulated mostly as a monomer in thylakoid membranes. The PSII monomers purified from the CGM thylakoids bound echinenone and canthaxanthin in addition to β-carotene, suggesting that a shortage of β-carotene and/or the binding of carbonyl carotenoids would interfere with the photophysical function as well as normal assembly of PSII. In contrast, high accumulation of astaxanthin and other carbonyl carotenoids was found within the thylakoid membranes. This finding would be associated with the suppression of photo-oxidative stress in the thylakoid membranes. Our observation suggests the importance of a specific balance between photoprotection and photoinhibition that can support normal photosynthesis in CGM lettuce producing astaxanthin. © The Author 2015. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  6. RNAi-mediated resistance to whitefly (Bemisia tabaci) in genetically engineered lettuce (Lactuca sativa).

    Science.gov (United States)

    Ibrahim, Abdulrazak B; Monteiro, Tatiane R; Cabral, Glaucia B; Aragão, Francisco J L

    2017-10-01

    RNA interference (RNAi)-based transgenic technologies have evolved as potent biochemical tools for silencing specific genes of plant pathogens and pests. The approach has been demonstrated to be useful in silencing genes in insect species. Here, we report on the successful construction of RNAi-based plasmid containing an interfering cassette designed to generate dsRNAs that target a novel v-ATPase transcript in whitefly (Bemisia tabaci), an important agricultural pest in tropical and sub-tropical regions. The presence of the transgene was confirmed in T 0 and T 1 generations of transgenic lettuce lines, segregating in a Mendelian fashion. Seven lines were infested with whiteflies and monitored over a period of 32 days. Analysis of mortality showed that within five days of feeding, insects on transgenic plants showed a mortality rate of 83.8-98.1%. In addition, a reduced number of eggs (95 fold less) was observed in flies feeding on transgenic lettuce plants than insects on control lines. Quantitative reverse transcription PCR showed decreased expression level of endogenous v-ATPase gene in whiteflies feeding on transgenic plants. This technology is a foundation for the production of whitefly-resistant commercial crops, improving agricultural sustainability and food security, reducing the use of more environmentally aggressive methods of pest control.

  7. Nutritional value, bioactive compounds, and health benefits of lettuce (Lactuca sativa L.)

    Science.gov (United States)

    Lettuce is one of the most popularly consumed vegetables worldwide but its nutritional value has been underestimated. Lettuce is low in calories and fat but high in fiber. Moreover, lettuce is high in potassium but low in sodium. Lettuce is also a good source of health-beneficial bioactive compounds...

  8. NUTRIENTS DYNIMIC IN AN AQUAPONIC RECIRCULATING SYSTEM FOR STURGEON AND LETTUCE (LACTUCA SATIVA PRODUCTION

    Directory of Open Access Journals (Sweden)

    LORENA SFETCU

    2008-10-01

    Full Text Available Aquaponics are modern production systems, which integrate the aquaculture technology with hydroponic systems (vegetable production without soil with a goal of fructification of residual nutrients resulted from metabolic activity of fish biomass as high quality vegetable biomass sealable as ecological products. In the present study, as a first step in aquaponic recirculating systems evaluation, the authors aim to compare two types of recirculating systems: classical (hereby noted with RAS and integrated/aquaponic (RAS_A regarding water quality parameters generally, and TAN (total ammonia nitrogen production and transformation, particularly.

  9. Phloem sap collection from lettuce (Lactuca sativa L.): Methodology and yield.

    Science.gov (United States)

    van Helden, M; Tjallingii, W F; van Beek, T A

    1994-12-01

    Three methods to collect phloem sap on different lettuce lines were optimized and are described in detail. The success ratio for stylectomy of aphids was over 80% through the combination of a specially designed setup and electrical penetration graphs to monitor phloem sap ingestion. For unknown reasons on some lettuce lines stylets never showed sustained exudation. There were clear differences in stylet exudation between two aphid species on the same lettuce line. Honeydew collection in hexadecane made accurate quantitative analysis possible; samples were large and clean, but biotransformed. The EDTA chelation method produced large samples, but dilution, oxidation, and impurities from the wound surface reduced the reliability.

  10. Characterization and biocontrol properties of Lactuca sativa rhizosphere microbiota in an aquaponic system

    OpenAIRE

    Stouvenakers, Gilles; Massart, Sébastien; Jijakli, Haissam

    2016-01-01

    Aquaponics is an integrated recirculated system that combines aquaculture and hydroponic plant production. The dissolved nutrients generated by the fish rearing after bacterial activities are used by the plants for their growth. This uptake reduces the accumulation of some molecules which allow a longer water recirculation. When comparing growth conditions between aquaponics and hydroponics, we observed much lower concentration of several key nutrients in aquaponics. Nevertheless, several exp...

  11. Occupational contact dermatitis from Cichorium (chicory, endive) and Lactuca (lettuce).

    Science.gov (United States)

    Friis, B; Hjorth, N; Vail, J T; Mitchell, J C

    1975-10-01

    In two cases, occupational contact dermatitis was found to be due to chicory (Cichorium) used as a salad plant. In one of the two cases, contact sensitivity to letuce (Lactuca) was also observed. The sesquiterpene lactones of the plant may be the allergens.

  12. Lactuca serriola (Asteraceae, a Newly Naturalized Plant in Taiwan

    Directory of Open Access Journals (Sweden)

    Chiu-Mei Wang

    2010-09-01

    Full Text Available A newly naturalized herb was recently recorded here. Lactuca serriola L. (Asteraceae was found in the central part of western Taiwan and Penghu island, as an alien weed. This report gives taxonomic descriptions and illustrations. Photographs are also provided for identification.

  13. Changes in Microtubular Alignment in Lactuca spp. (Asteraceae) Epidermal Cells during Early Stages of Infection by Bremia lactucae (Peronosporaceae)

    Czech Academy of Sciences Publication Activity Database

    Sedlářová, M.; Binarová, Pavla; Lebeda, A.

    2001-01-01

    Roč. 41, č. 1 (2001), s. 21-34 ISSN 0079-2047 R&D Projects: GA AV ČR IAA5020803; GA MŠk ME 397 Institutional research plan: CEZ:AV0Z5038910 Keywords : Bremia lactucae * Peronosporaceae * resistance Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 0.275, year: 2001

  14. Medicago sativa spp. falcata

    African Journals Online (AJOL)

    STORAGESEVER

    2009-05-18

    May 18, 2009 ... Falcata (Medicago sativa spp. falcata L.), with its high resistance to cold weather, drought and disease, .... 40 plants. Seeds were grown in a greenhouse and seedlings were transplanted three months later to the experiment station in Hebei province ..... latitude range (from northern latitude 29° to northern.

  15. Oryza sativa L.

    Indian Academy of Sciences (India)

    Molecular evaluation of genetic diversity and association studies in rice. (Oryza sativa L.) C. Vanniarajan, K. K. Vinod and Andy Pereira. J. Genet. 91, 9–19. Table 1. Chromosome-wise distribution of SSR alleles and their number (k), polymorphic information content (PIC) and allele discrimination index (Dm). Chromosome.

  16. Cinza vegetal na germinação e no desenvolvimento da alface

    Directory of Open Access Journals (Sweden)

    Marcelo Alves Terra

    2014-01-01

    Full Text Available O objetivo deste trabalho foi avaliar o efeito da cinza vegetal na germinação e no desenvolvimento da alface da variedade Lucy Brown, tipo americana. O tipo escolhido foi semeado em bandejas de isopor com cento e vinte oito células. As bandejas continham os seguintes substratos: cinza vegetal, esterco bovino, casca arroz crua, casca de arroz carbonizada, serragem, misturados com solo na proporção de 1:1, além de substrato comercial, solo com adubação de NPK e solo sem adubação. Após o início da germinação, as plântulas foram contadas de três em três dias. Mudas de alface da mesma variedade com três folhas verdadeiras foram transplantadas para caixas de leite com os mesmos substratos. Trinta e três dias após o transplante, a alface foi colhida, as folhas foram contadas, a biomassa verde e a biomassa seca foram determinadas e os caules e as raízes foram contados. O substrato que proporcionou a maior germinação foi a mistura de solo com esterco. Depois, vieram o substrato comercial, o solo com casca de arroz carbonizada, o solo puro, o solo com casca de arroz crua, o solo com NPK, o solo com serragem e o solo com cinza vegetal. Neste último, germinaram apenas de 7,83% das sementes. No momento da colheita, verificou-se, para todos os parâmetros avaliados, com exceção do peso seco da raiz, que o substrato que proporcionou o melhor desenvolvimento foi o solo com esterco bovino, que se diferenciou estatisticamente dos demais substratos avaliados. A cinza vegetal influenciou negativamente tanto na germinação quanto no desenvolvimento das plantas de alface.

  17. Produção de cultivares de alface americana sob dois sistemas de cultivo

    Directory of Open Access Journals (Sweden)

    Cristian Rafael Brzezinski

    Full Text Available RESUMO A alface é cultivada em todas as regiões brasileiras, porém há restrições ao seu cultivo em virtude de sua sensibilidade às condições adversas de temperatura, umidade do ar e disponibilidade de água. Diante disto, objetivou-se, com este experimento, avaliar a produção de quatro cultivares de alface americana, sob dois sistemas de cultivo. O delineamento experimental utilizado foi o de blocos ao acaso, em esquema de parcelas subdivididas. As parcelas foram constituídas por dois sistemas de cultivo (túnel baixo de polietileno e campo aberto, e, as subparcelas por quatro cultivares de alface americana (Angelina, Rubette, Grandes Lagos 659 e Tainá, com quatro repetições. As características avaliadas foram: altura de plantas, diâmetro total da planta, diâmetro transversal da cabeça, comprimento de caule, diâmetro de caule, massa de matéria fresca de caule, número de folhas comerciais e não comerciais, massa de matéria fresca comercial e não comercial. Foi realizada análise de variância e as médias foram comparadas pelo teste de Tukey. O túnel baixo favorece o crescimento e a produção de cultivares de alface americana, em relação ao campo aberto. O cultivar Rubette mostra crescimento e produção superiores aos demais cultivares avaliados, nos dois sistemas de cultivo.

  18. DESENVOLVIMENTO VEGETATIVO DE MUDAS DE ALFACE EM DIFERENTES SUBSTRATOS ORGÂNICOS

    Directory of Open Access Journals (Sweden)

    Rebyson Bissaco Guidinelle

    2017-04-01

    Full Text Available O objetivo do trabalho foi avaliar a produção de mudas de alface dos cultivares Mônica e Regina, em diferentes tipos de substrato orgânicos, buscando formas alternativas na sua produção. O experimento foi conduzido em casa de vegetação utilizando três substratos, S1 - Comercial; S2 - Vermicomposto; S3 - Serrapilheira. Foi avaliado os parâmetros morfoagronômicos do comprimento das mudas, sendo; altura parte aérea, comprimento da maior raiz e altura total. Os substratos apresentaram diferenças significativas entre si, sendo que a Serrapilheira apresentou os melhores resultados de desenvolvimento vegetativo juntamente com o vermicomposto. Concluindo-se que a produção de mudas de alface pode ser feita a partir de substratos orgânicos, recomendando a substituição total dos substratos comerciais, visando menor custo na produção, mas garantindo boa produtividade e qualidade das mudas de alface.

  19. DESENVOLVIMENTO DE MUDAS DE ALFACE EM DIFERENTES SUBSTRATOS E CONCENTRAÇÕES

    Directory of Open Access Journals (Sweden)

    Mário Pechara Jaeggi

    2017-04-01

    Full Text Available Objetivou-se com este trabalho avaliar o desempenho de diferentes substratos e concentrações, no desenvolvimento de cultivares de alface. O experimento foi conduzido em casa de vegetação, localizada no setor de Agroecologia do Instituto Federal do Espírito Santo Campus de Alegre, ES. O delineamento utilizado foi em blocos casualizados disposto em um esquema fatorial 4x3x2, sendo quatro tipos substratos (S1: Plantmax®; S2: composto orgânico; S3: húmus de minhoca; S4: borra de cana-de-açúcar, três concentrações (100%, 75% e 50% e duas cultivares de alface. As variáveis avaliadas foram: massa fresca da parte aérea, massa fresca toal e altura da parte aérea. As mudas foram avaliadas ao 21° dia após semeio. Os resultados demostraram que substratos orgânicos se mostraram eficazes para o desenvolvimento das cultivares de alface, os quais podem ser utilizados em diferentes concentrações em substituição ao substrato comercial.

  20. CRESCIMENTO DA ALFACE EM TÚNEIS BAIXOS COM FILME DE POLIETILENO PERFURADO

    Directory of Open Access Journals (Sweden)

    Nereu Augusto Streck

    1994-01-01

    Full Text Available RESUMO Determinou-se o efeito do filme de polietileno perfurado, em túneis baixos, sobre o crescimento da alface em Santa Maria, RS. Os tratamentos, realizados em canteiros de 1,00m x 12,00m x 0,10m, constituiram-se de túneis baixos cobertos com polietileno de baixa densidade e transparente com 0,78% (T1, 1,57% (T2, 2,35% (T3 e 3,14% (T4 de área perfurada e a testemunha sem túnel (T. Utilizou-se a cultivar de alface White Boston, grupo "Lisa", no período de inverno (23.05.91 a 08.08.91 e a cultivar Hampson, grupo "Crespa", no período de primavera (30.08.91 a 30.10.91. Foram feitas determinações da massa da matéria seca do caule e das folhas, área foliar, número de folhas e comprimento do caule. O tratamento que proporcionou maior crescimento das plantas de alface foi o T1 no período invernal e o T3 no período primaveril.

  1. (Vicia sativa L.) - triticale

    African Journals Online (AJOL)

    STORAGESEVER

    2009-10-19

    Oct 19, 2009 ... vetch (Vicia sativa L.) - triticale (Triticosecale Wittm.) mixtures under east mediterranean rainfed .... that the grain yield of pea and oats averaged 4.9 t ha-1 in monocultures and 5.5 t ha-1 in mixtures ... The long-term average temperature from November to April in Kozan is 13.0°C and means rainfall 537 mm ...

  2. Cadmium effects on growth and physiology of Ulva lactuca

    Energy Technology Data Exchange (ETDEWEB)

    Markham, J.W.; Kremer, B.P.; Sperling, K.R.

    1980-01-01

    The chlorophycean Ulva lactuca L. was grown in the laboratory in unialgal culture to sufficient size so that up to 70 discs, 24 mm in diameter, could be punched out of a single plant. Using such discs, U. lactuca was then tested with various concentrations of Cd under continuous-flow conditions. A concentration of 4.5 ppm Cd was lethal to U. lactuca within 6 days. Control discs in unpolluted water increased in diameter at a rate of 8 to 13% day/sup -1/ over a 6-day period. At sublethal concentration of Cd a sharp reduction in growth rate was observed at increasing concentrations up to approximately 0.3 ppm Cd, whereas from 0.3 ppm Cd to the lethal concentrations the reduction of the growth rate was significantly less. Reduction in photosynthetic performance corresponded closely to the recuction in growth rate. At ambient concentrations of 0.8 ppm Cd, the plants concentrated Cd by a factor of approximately 50 in 6 days. Much higher concentration factors were attained in lower ambient concentrations. After removal from Cd-polluted water into flow-through culture in unpolluted water, a subsequent loss of Cd was indicated and the plants recovered rapidly. Plants exposed up to 3 d to 0.7 ppm Cd recovered sufficiently to produce viable gametes 7 days after removal from Cd. Because it has a relatively short life span and apparently loses Cd subsequent to exposure to Cd-polluted water, Ulva lactuca is not recommended as an alga for monitoring in-situ environmental pollution.

  3. Co-biosorption of copper and glyphosate by Ulva lactuca.

    Science.gov (United States)

    Trinelli, María Alcira; Areco, María Mar; Afonso, María dos Santos

    2013-05-01

    This study investigated the adsorption of glyphosate (PMG) onto the green algae Ulva lactuca. PMG was not adsorbed by U. lactuca but PMG was adsorbed when the process was mediated by Cu(II) with molar ratios Cu(II):PMG≥1.5:1. U. lactuca was characterized by water adsorption surface area, FTIR, SEM and EDS. The Langmuir and Freundlich models were applied. Results showed that the biosorption processes for copper and PMG in the presence of copper were described described by the Langmuir model (qmax=0.85±0.09 mmol g(-1), KL=0.55±0.14 l mmol(-1) and qmax=3.65±0.46 mmol g(-1), KL=0.103±0.03 l mmol(-1), respectively). Copper adsorption was greater in the presence of PMG than in the absence of the pesticide and the adsorption can only be represented by the Freundlich model (KF=0.08±0.01, 1/n=1.86±0.07). In all cases studied, the maximum metal uptake (qmax) increased with increasing pH. Surface complexes with a stoichiometry ranging from ≡Cu-PMG-Cu to ≡Cu-PMG-Cu3 are suggested as reaction products of the process. Due to the increasing amounts of PMG applied in Argentina, natural reservoirs present considerable amounts of this herbicide. The value of this work resides in using U. lactuca, a marine seaweed commonly found along coastlines all over the world, as a biosorbent for PMG. Copyright © 2013 Elsevier B.V. All rights reserved.

  4. Fertirrigação com vinhaça concentrada no desenvolvimento da alface

    Directory of Open Access Journals (Sweden)

    Alexandre Barcellos Dalri

    2014-06-01

    Full Text Available A grande vantagem no emprego da vinhaça concentrada é que ela pode substituir em grande parte os nutrientes da adubação mineral. O uso agrícola da vinhaça concentrada como biofertilizante e os seus benefícios ao solo e às plantas são indiscutíveis. O objetivo desse estudo foi estudar o efeito do uso de vinhaça concentrada, denominada de biofertilizante, em combinação com fertilizantes comerciais, aplicados via fertirrigação, nos componentes de produção da cultura da alface. O experimento foi instalado em ambiente protegido localizado na região centro-norte do Estado de SP. A cultivar utilizada foi a Verônica, o delineamento foi inteiramente casualizado e os tratamentos foram doses de vinhaça concentrada que variaram de 50% a 250% da referência da adubação convencional de potássio. As variáveis analisadas da alface foram: massa fresca total (MFT massa fresca comercial (MFC, diâmetro do caule (DC, comprimento do caule (CC e número de folhas (NF. O uso da vinhaça concentrada como biofertilizante líquido proporciona aumento significativo nas principais características morfológicas da alface, resultando em plantas maiores, com maior número de folhas e maior massa fresca. Esse biofertilizante mostra-se realmente eficaz no aumento da produtividade da cultura da alface. Para as condições em que este trabalho foi realizado, pode-se concluir que a aplicação, via fertirrigação, de 2,97 m3 ha-1 de vinhaça concentrada e enriquecida com nitrogênio atende a adubação da cultura da alface.

  5. Genetic dissection of Lactuca saligna nonhost resistance to downy mildew at various lettuce developmental stages

    NARCIS (Netherlands)

    Zhang, N.; Lindhout, P.; Niks, R.E.; Jeuken, M.J.W.

    2009-01-01

    This study used the pathosystem of lettuce (Lactuca spp.) and downy mildew (Bremia lactucae) as a model to investigate the inheritance of nonhost resistance, and focused on the contribution of quantitative trait loci (QTLs) to nonhost resistance at various developmental stages in the lettuce life

  6. Factors affecting the survival of Bremia lactucae sporangia deposited on lettuce leaves

    NARCIS (Netherlands)

    Wu, B.M.; Subbarao, K.V.; Bruggen, van A.H.C.

    2000-01-01

    Experiments to identify the factors affecting survival of Bremia lactucae sporangia after deposition on lettuce leaves were conducted in growth chambers and outdoors under ambient conditions. Lettuce seedlings at the four-leaf stage were inoculated with B. lactucae sporangia under dry conditions.

  7. OCORRÊNCIA DE ENTEROPATÓGENOS EM ALFACES E SUAS ÁGUAS DE IRRIGAÇÃO

    Directory of Open Access Journals (Sweden)

    Paulo Roberto Martins BONILHA

    2009-07-01

    Full Text Available

    RESUMO: Foram analisadas cinqüenta amostras de água de irrigação, cinqüenta de alface não lavada e cinqüenta de alface lavada com água tratada, coletadas em hortas situadas na cidade de Araraquara, SP, Brasil. A partir de cada uma das amostras, foram realizadas as seguintes análises: determinação do NMP de coliformes totais, coliformes fecais e Escherichia coli; pesquisa de salmonella, Shigella, E. coli enteropatogênica clássica (EPEC, E. coli enteroinvasora (EIEC, Yersina e, eventualmente, outros patógenos detectados pelas técnicas utilizadas; determinação da sensibilidade a drogas, das amostras de enteropatógenos isolados. A análise estatística demonstrou haver correlação significativa apenas entre o grau de contaminação por coliformes fecais e E. coli nas amostras de água de irrigação e de alface não lavada. Após a lavagem das alfaces as medianas dos percentuais de redução foram: 81,4% para coliformes totais, 99,9% para coliformes fecais e 97,4% para E. coli. Foram isoladas, na água de irrigação, Salmonella Miami, S. bredney, S. abaeteuba, E. coli 0:26 e Aeromonas hydrophila. Em uma amostra de alface não lavada, S. miami. Nas amostras de alface lavada, foram isoladas S. Miami e A. hydrophila. Apenas a S. Miami foi detectada nas amostras paralelas, de água de irrigação, de alface não lavada e de alface lavada. Não foram isoladas, em nenhuma das amostras, Shigella, Yersina e E. coli enteroinvasora. Das oito amostras de enteropatógenos isolados, sete apresentaram resistência múltipla a drogas, enquanto a cepa de E. coli 0:26 só foi resistente à novobiocina. PALAVRAS-CHAVE: Hortaliças; coliformes; enteropatógenos.

  8. OCORRÊNCIA DE ENTEROPATÓGENOS EM ALFACES E SUAS ÁGUAS DE IRRIGAÇÃO

    OpenAIRE

    Paulo Roberto Martins BONILHA; Deise Pasetto FALCÃO

    2009-01-01

    RESUMO: Foram analisadas cinqüenta amostras de água de irrigação, cinqüenta de alface não lavada e cinqüenta de alface lavada com água tratada, coletadas em hortas situadas na cidade de Araraquara, SP, Brasil. A partir de cada uma das amostras, foram realizadas as seguintes análises: determinação do NMP de coliformes totais, coliformes fecais e Escherichia coli; pesquisa de salmonella, Shigella, E. coli enteropatogênica clássica (EPEC), E. coli enteroinvasora (EIEC), ...

  9. Alfalfa (Medicago sativa L.).

    Science.gov (United States)

    Fu, Chunxiang; Hernandez, Timothy; Zhou, Chuanen; Wang, Zeng-Yu

    2015-01-01

    Alfalfa (Medicago sativa L.) is a high-quality forage crop widely grown throughout the world. This chapter describes an efficient protocol that allows for the generation of large number of transgenic alfalfa plants by sonication-assisted Agrobacterium-mediated transformation. Binary vectors carrying different selectable marker genes that confer resistance to phosphinothricin (bar), kanamycin (npt II), or hygromycin (hph) were used to generate transgenic alfalfa plants. Intact trifoliates collected from clonally propagated plants in the greenhouse were sterilized with bleach and then inoculated with Agrobacterium strain EHA105. More than 80 % of infected leaf pieces could produce rooted transgenic plants in 4-5 months after Agrobacterium-mediated transformation.

  10. Influência das épocas de cultivo e do estabelecimento do consórcio na produção de tomate e alface consorciados

    OpenAIRE

    Rezende,Bráulio Luciano Alves; Canato,Gustavo Henrique Domingues; Cecílio Filho,Arthur Bernardes

    2005-01-01

    Conduziu-se este trabalho na UNESP, Jaboticabal-SP, em duas épocas de cultivo, julho a novembro de 2001 e fevereiro a agosto de 2002, com o objetivo de avaliar a produtividade das culturas de tomate e de alface em cultivo consorciado, em função da época de estabelecimento do consórcio. Em cada época, foram avaliados nove tratamentos, sendo os consórcios e os monocultivos de alface estabelecidos aos zero, 14, 28 e 42 dias após o transplantio do tomateiro. As cultivares de tomate e alface foram...

  11. Emergência e crescimento inicial de mudas de cultivares de alface em diferentes substratos

    Directory of Open Access Journals (Sweden)

    Regiana dos Santos Moura

    2015-05-01

    Full Text Available Resumo: Objetivou-se avaliar os efeitos de combinações de substratos na emergência e crescimento inicial de diferentes cultivares de alface. O estudo foi conduzido em ambiente de telado, no Setor de Horticultura da Universidade Federal do Piauí, no Campus Professora Cinobelina Elvas, em Bom Jesus - PI. Compararam-se as combinações de substratos: biomix® (S1, esterco bovino (S2, paú de buriti (S3, paú de buriti + areia lavada + esterco bovino na proporção de 1:1:1 (S4, paú de buriti + areia lavada na proporção de 1:1 (S5, paú de buriti + esterco bovino na proporção de 1:1 (S6, areia lavada + esterco bovino na proporção de 1:1 (S7 e três cultivares de alface: Solaris, Lucy Brown e Florence. O delineamento experimental utilizado foi o inteiramente casualizado, em esquema fatorial 7x3, com quatro repetições e 50 sementes por parcela. O substrato S5 (Paú de buriti + esterco bovino na proporção de 1:1 foi o que mais proporcionou condições favoráveis para a emergência das plântulas de alface. As plântulas cultivadas no substrato S1 (Biomix® apresentaram maior crescimento inicial. Tanto na emergência quanto no crescimento inicial, as cultivares Solaris e Lucy Brown foram as que apresentaram os melhores resultados.

  12. Fungo Metarhizium anisopliae e o controle de Frankliniella occidentalis em alface hidropônico

    Directory of Open Access Journals (Sweden)

    Lopes Rogério Biaggioni

    2000-01-01

    Full Text Available O tripes Frankliniella occidentalis (Pergande provoca grandes prejuízos em cultivos comerciais de alface, através do dano direto, durante a alimentação no tecido vegetal, e pela transmissão de virose. O desenvolvimento de novas estratégias de controle da praga em cultivos protegidos vem se tornando necessária em função dos problemas acarretados pelo uso constante de inseticidas químicos. Foi avaliada a eficiência de pulverizações do fungo Metarhizium anisopliae (Metsch. Sorokin (isolado 1104 nas concentrações 5x10(6 e 1x10(8 conídios ml-1, visando o controle da praga em cultivos de alface hidropônico. A eficiência de controle do fungo nas duas concentrações chegou a 60%, seis dias após a primeira pulverização. Nas parcelas que não receberam o tratamento com o patógeno, observou-se um aumento populacional de 46,5%. Contudo, o número de adultos capturados em armadilhas adesivas foi semelhante para áreas tratadas e não tratadas, devido à alta mobilidade da praga na cultura. Constatou-se também um número crescente de adultos mortos com estruturas do patógeno, nas parcelas pulverizadas com o fungo. A ausência de toxicidade e de período de carência dos fungos entomopatogênicos torna estes microrganismos importantes na substituição de alguns inseticidas químicos na cultura do alface. Estudos mais detalhados sobre a utilização de M. anisopliae em cultivos protegidos são necessários para aplicações em grande escala.

  13. Coeficiente de cultura da alface hidropônica baseado no conceito de graus-dia

    OpenAIRE

    Moura, Carlos Roberto Weide; Zolnier, Sérgio; Ribeiro, Aristides; Oliveira, Rubens Alves de

    2010-01-01

    O objetivo principal deste trabalho foi propor a adoção de um coeficiente de cultura térmico, com a aplicação do conceito de graus-dia acumulados após o transplantio, para estimativa da evapotranspiração diária (ETc) dos cultivares de alface Grand Rapids, Regina e Great Lakes em sistema hidropônico do tipo NFT ("nutrient film technique"), em ambiente protegido. Posteriormente, o modelo matemático ajustado ãos valores observados de Kc (coeficiente de cultura) foi utilizado para a estimativa de...

  14. DESENVOLVIMENTO DE MUDAS DE ALFACE EM DIFERENTES SUBSTRATOS E CONCENTRAÇÕES

    OpenAIRE

    Mário Pechara Jaeggi; Julio Gradice Saluci; Maxwel Rodrigues Nascimento; Rogerio Rangel Rodrigues; Samuel Ferreira Silva; Andre Oliveira Souza; Alex Justino Zacarias; Israel Martins Pereira; Rebson Bissaco Guidinelle; Wallace Luis Lima

    2017-01-01

    Objetivou-se com este trabalho avaliar o desempenho de diferentes substratos e concentrações, no desenvolvimento de cultivares de alface. O experimento foi conduzido em casa de vegetação, localizada no setor de Agroecologia do Instituto Federal do Espírito Santo Campus de Alegre, ES. O delineamento utilizado foi em blocos casualizados disposto em um esquema fatorial 4x3x2, sendo quatro tipos substratos (S1: Plantmax®; S2: composto orgânico; S3: húmus de minhoca; S4: borra de cana-de-açúcar), ...

  15. Qualidade da muda e produtividade de alface orgânica com condicionadores de substrato

    OpenAIRE

    Simões,Antônio C; Alves,Gisley KEB; Ferreira,Regina LF; Araújo Neto,Sebastião E

    2015-01-01

    RESUMO: O uso dos resíduos orgânicos como componentes de substrato para produção de mudas de hortaliças propicia a obtenção de materiais alternativos, de fácil disponibilidade e baixo custo. O objetivo do trabalho foi avaliar o efeito de condicionadores de substratos na qualidade da muda orgânica e o efeito dessas mudas sobre a produtividade da alface em sistema orgânico. O delineamento experimental foi em blocos casualizados com seis tratamentos e quatro repetições. Os tratamentos constaram ...

  16. Cinza vegetal na germinação e no desenvolvimento da alface

    OpenAIRE

    Marcelo Alves Terra; Fernanda Ferreira Leonel; Carla Gomes da Silva; Andersom Maciel Fonseca

    2014-01-01

    O objetivo deste trabalho foi avaliar o efeito da cinza vegetal na germinação e no desenvolvimento da alface da variedade Lucy Brown, tipo americana. O tipo escolhido foi semeado em bandejas de isopor com cento e vinte oito células. As bandejas continham os seguintes substratos: cinza vegetal, esterco bovino, casca arroz crua, casca de arroz carbonizada, serragem, misturados com solo na proporção de 1:1, além de substrato comercial, solo com adubação de NPK e solo sem adubação. Após o início ...

  17. DESENVOLVIMENTO VEGETATIVO DE MUDAS DE ALFACE EM DIFERENTES SUBSTRATOS ORGÂNICOS

    OpenAIRE

    Rebyson Bissaco Guidinelle; Israel Martins Pereira; Alex Justino Zacarias; Mário Euclides Pechara da Costa Jaeggi; Julio Cesar Gradice Saluci; Maxwel Rodrigues Nascimento; Samuel Ferreira da Silva; Rogério Rangel Rodrigues; Wallace Luís de Lima

    2017-01-01

    O objetivo do trabalho foi avaliar a produção de mudas de alface dos cultivares Mônica e Regina, em diferentes tipos de substrato orgânicos, buscando formas alternativas na sua produção. O experimento foi conduzido em casa de vegetação utilizando três substratos, S1 - Comercial; S2 - Vermicomposto; S3 - Serrapilheira. Foi avaliado os parâmetros morfoagronômicos do comprimento das mudas, sendo; altura parte aérea, comprimento da maior raiz e altura total. Os substratos apresentaram diferenças ...

  18. Interações agroeconômicas de alface e rúcula

    OpenAIRE

    Oliveira, Eliane Queiroga de

    2014-01-01

    Este trabalho foi realizado com o objetivo principal de avaliar a interação de alface e rúcula, sob aspectos biológicos e econômicos, em função de arranjos espaciais de plantio e sistemas de cultivo agrícola. O comportamento e o efeito das relações biológicas entre os organismos, especificamente as culturas que compõem os agrossistemas com hortaliças, ainda necessitam de muitos estudos. Assim, foram feitos quatro experimentos na Universidade Federal de Lavras (UFLA), no período de fevereiro a...

  19. (Nigella sativa L.) genotypes from

    African Journals Online (AJOL)

    ajl yemi

    2011-10-26

    Coriandrum sativum L.) and. Niger (Guizotia abyssinica cass.) oil seeds. Food Chem. 80: 197-204. Ramadan MF, Morsel JT (2002). Characterization of phospholipids composition of black cumin (Nigella sativa). Nahrung/Food, 46: 240-.

  20. Hemp (Cannabis sativa L.).

    Science.gov (United States)

    Feeney, Mistianne; Punja, Zamir K

    2015-01-01

    Hemp (Cannabis sativa L.) suspension culture cells were transformed with Agrobacterium tumefaciens strain EHA101 carrying the binary plasmid pNOV3635. The plasmid contains a phosphomannose isomerase (PMI) selectable marker gene. Cells transformed with PMI are capable of metabolizing the selective agent mannose, whereas cells not expressing the gene are incapable of using the carbon source and will stop growing. Callus masses proliferating on selection medium were screened for PMI expression using a chlorophenol red assay. Genomic DNA was extracted from putatively transformed callus lines, and the presence of the PMI gene was confirmed using PCR and Southern hybridization. Using this method, an average transformation frequency of 31.23% ± 0.14 was obtained for all transformation experiments, with a range of 15.1-55.3%.

  1. Hemp (Cannabis sativa L.).

    Science.gov (United States)

    Feeney, Mistianne; Punja, Zamir K

    2006-01-01

    Hemp (Cannabis sativa L.) suspension culture cells were transformed with Agrobacterium tumefaciens strain EHA101 carrying the binary plasmid pNOV3635. The plasmid contains a phosphomannose isomerase (PMI) selectable marker gene. Cells transformed with PMI are capable of metabolizing the selective agent, mannose, whereas cells not expressing the gene are incapable of using the carbon source and will stop growing. Callus masses proliferating on selection were screened for PMI expression using a chlorophenol red assay. Genomic DNA was extracted from putatively transformed callus lines and the presence of the PMI gene was confirmed using polymerase chain reaction and Southern hybridization. Using this method, an average transformation frequency of 31.23% +/- 0.14 was obtained for all transformation experiments, with a range of 15.1 to 55.3%.

  2. USO DE SUBSTRATOS ORGÂNICOS PARA PRODUÇÃO DE MUDAS DE ALFACE

    Directory of Open Access Journals (Sweden)

    Israel Martins Pereira Martins

    2017-05-01

    Full Text Available O trabalho teve como objetivo avaliar o efeito de substratos orgânicos na produção de mudas de alface. O delineamento experimental utilizado foi o inteiramente casualizado (DIC disposto em esquema fatorial 3x2, sendo constituídas por três substratos duas cultivares se alface (Regina e Mônica. Em bandejas de isopor que continham os diferentes substratos: Comercial, Vermicomposto e Serapilheira. Estudaram-se as variáveis: a avaliados foram massa fresca parte aérea (MFPA obtida a partir da pesagem da parte aérea da plântula, b massa fresca sistema radicular (MFSR, obtido pelo peso da raiz lavada sobre uma peneira de malha fina usando água corrente, c massa fresca total (MFT obtida através da soma da MFPA+MFSR e número de folhas (NFT, contando-se as unidades de folhas, foram avaliadas após 25 dias emergência das sementes. Obtendo-se valores significativos, percebeu-se que o substrato de Vermicomposto se sobressaiu com resultado melhor que o composto Comercial e Serapilheira

  3. Bioenergy potential of Ulva lactuca: Biomass yield, methane production and combustion

    DEFF Research Database (Denmark)

    Bruhn, Annette; Dahl, Jonas; Bangsø Nielsen, Henrik

    2011-01-01

    The biomass production potential at temperate latitudes (56°N), and the quality of the biomass for energy production (anaerobic digestion to methane and direct combustion) were investigated for the green macroalgae, Ulva lactuca. The algae were cultivated in a land based facility demonstrating...... a production potential of 45 T (TS) ha−1 y−1. Biogas production from fresh and macerated U. lactuca yielded up to 271 ml CH4 g−1 VS, which is in the range of the methane production from cattle manure and land based energy crops, such as grass-clover. Drying of the biomass resulted in a 5–9-fold increase...... in weight specific methane production compared to wet biomass. Ash and alkali contents are the main challenges in the use of U. lactuca for direct combustion. Application of a bio-refinery concept could increase the economical value of the U. lactuca biomass as well as improve its suitability for production...

  4. Botanical files on Lettuce (Lactuca sativa) - on the chance for gene flow between wild and cultivated Lettuce (Lactuca sativa L., including L. serriola L., Compositae) and the generalized implications for risk-assessments on genetically modified plants

    NARCIS (Netherlands)

    Frietema, de F.T.; Meijden, van der R.; Brandenburg, W.A.

    1995-01-01

    In Botanical Files, a study of the real chances for gene flow from cultivated plants to the wild a system of dispersal codes (Dpdf) was introduced (see text box Dpdf).³7 They are indications of already occurring gene flow from cultivated plants to the wild flora, as can be deduced from herbarium

  5. Botanical Files on Lettuce (Lactuca sativa). On the chance for gene flow between wild and cultivated Lettuce (Lactuca sativa L. including L. serriola L., Compositae) and the generalized implications for risk-assessments on genetically modified plants

    NARCIS (Netherlands)

    Frietema de Vries, F.T.; Meijden, van der R.; Brandenburg, W.A.

    1994-01-01

    In Botanical Files, a study of the real chances for gene flow from cultivated plants to the wild a system of dispersal codes (Dpdf) was introduced (see text box Dpdf).³7 They are indications of already occurring gene flow from cultivated plants to the wild flora, as can be deduced from herbarium

  6. Qualidade pós-colheita da alface hidropônica em ambiente protegido sob malhas termorefletoras e negra

    Directory of Open Access Journals (Sweden)

    Patrícia Lígia Dantas de Morais

    2011-10-01

    Full Text Available Considerando que a duração da exposição, a qualidade e intensidade de luz afetam as características de qualidade das hortaliças folhosas, conduziu-se um experimento, em ambiente protegido, com o objetivo de avaliar a qualidade pós-colheita da alface hidropônica, sob os efeitos das malhas de sombreamento, com diferentes percentagens de atenuação da radiação solar. O delineamento experimental foi o de blocos casualizados, no esquema fatorial 2 x 5, com três repetições, sendo os tratamentos constituídos por quatro malhas termorefletoras (40; 50; 60 e 70% de sombreamento e uma testemunha, com malha negra 50%. Em cada parcela, representada por um sistema hidropônico individual, foi cultivada a alface (cv. Olinda, Crespa, sendo avaliada sua qualidade por ocasião da colheita e após quatro dias de armazenamento refrigerado (7,6 ± 1ºC e 27 ± 5 % UR. Observou-se que o excesso de sombreamento, ocasionado pelas malhas termorefletoras 60 e 70% e malha negra 50%, comprometeram a aparência da alface. As plantas submetidas ao sombreamento com a malha termorefletora 40% apresentaram menor perda de massa, ao final de quatro dias de armazenamento. Os graus de sombreamento ocasionados pelas malhas termorefletoras e pela malha negra não influenciaram nos teores de ácido cítrico, sólidos solúveis, vitamina C e clorofila total da alface.

  7. (Nigella sativa L.) genotypes from

    African Journals Online (AJOL)

    ajl yemi

    2011-10-26

    Oct 26, 2011 ... analysis. Five and six clusters were observed for nutritional characteristics and mineral nutrients respectively. Based on principal component analysis, ...... mechanism (s) for the relaxant effect of aqueous and macerated extracts from Nigella sativa on tracheal chains of guinea pig. BMC Pharmacol, 4: 1-6.

  8. Pharmacology of Marihuana (Cannabis sativa)

    Science.gov (United States)

    Maickel, Roger P.

    1973-01-01

    A detailed discussion of marihuana (Cannabis sativa) providing the modes of use, history, chemistry, and physiologic properties of the drug. Cites research results relating to the pharmacologic effects of marihuana. These effects are categorized into five areas: behavioral, cardiovascular-respiratory, central nervous system, toxicity-toxicology,…

  9. Sensitivity of salad greens (Lactuca sativa L. and Eruca sativa Mill.) exposed to crude extracts of toxic and non-toxic cyanobacteria.

    Science.gov (United States)

    Bittencourt-Oliveira, M C; Hereman, T C; Macedo-Silva, I; Cordeiro-Araújo, M K; Sasaki, F F C; Dias, C T S

    2015-05-01

    We evaluated the effect of crude extracts of the microcystin-producing (MC+) cyanobacteria Microcystis aeruginosa on seed germination and initial development of lettuce and arugula, at concentrations between 0.5 μg.L(-1) and 100 μg.L(-1) of MC-LR equivalent, and compared it to crude extracts of the same species without the toxin (MC-). Crude extracts of the cyanobacteria with MC (+) and without MC (-) caused different effects on seed germination and initial development of the salad green seedlings, lettuce being more sensitive to both extracts when compared to arugula. Crude extracts of M. aeruginosa (MC+) caused more evident effects on seed germination and initial development of both species of salad greens than MC-. Concentrations of 75 μg.L(-1) and 100 μg.L(-1) of MC-LR equivalent induced a greater occurrence of abnormal seedlings in lettuce, due to necrosis of the radicle and shortening of this organ in normal seedlings, as well as the reduction in total chlorophyll content and increase in the activity of the antioxidant enzyme peroxidase (POD). The MC- extract caused no harmful effects to seed germination and initial development of seedlings of arugula. However, in lettuce, it caused elevation of POD enzyme activity, decrease in seed germination at concentrations of 75 μg.L(-1) (MC-75) and 100 μg.L(-1) (MC-100), and shortening of the radicle length, suggesting that other compounds present in the cyanobacteria extracts contributed to this result. Crude extracts of M. aeruginosa (MC-) may contain other compounds, besides the cyanotoxins, capable of causing inhibitory or stimulatory effects on seed germination and initial development of salad green seedlings. Arugula was more sensitive to the crude extracts of M. aeruginosa (MC+) and (MC-) and to other possible compounds produced by the cyanobacteria.

  10. Sensitivity of salad greens (Lactuca sativa L. and Eruca sativa Mill. exposed to crude extracts of toxic and non-toxic cyanobacteria

    Directory of Open Access Journals (Sweden)

    MC. Bittencourt-Oliveira

    Full Text Available We evaluated the effect of crude extracts of the microcystin-producing (MC+ cyanobacteria Microcystis aeruginosa on seed germination and initial development of lettuce and arugula, at concentrations between 0.5 μg.L–1 and 100 μg.L–1 of MC-LR equivalent, and compared it to crude extracts of the same species without the toxin (MC–. Crude extracts of the cyanobacteria with MC (+ and without MC (– caused different effects on seed germination and initial development of the salad green seedlings, lettuce being more sensitive to both extracts when compared to arugula. Crude extracts of M. aeruginosa (MC+ caused more evident effects on seed germination and initial development of both species of salad greens than MC–. Concentrations of 75 μg.L–1 and 100 μg.L–1 of MC–LR equivalent induced a greater occurrence of abnormal seedlings in lettuce, due to necrosis of the radicle and shortening of this organ in normal seedlings, as well as the reduction in total chlorophyll content and increase in the activity of the antioxidant enzyme peroxidase (POD. The MC– extract caused no harmful effects to seed germination and initial development of seedlings of arugula. However, in lettuce, it caused elevation of POD enzyme activity, decrease in seed germination at concentrations of 75 μg.L–1 (MC-75 and 100 μg.L–1 (MC-100, and shortening of the radicle length, suggesting that other compounds present in the cyanobacteria extracts contributed to this result. Crude extracts of M. aeruginosa (MC– may contain other compounds, besides the cyanotoxins, capable of causing inhibitory or stimulatory effects on seed germination and initial development of salad green seedlings. Arugula was more sensitive to the crude extracts of M. aeruginosa (MC+ and (MC– and to other possible compounds produced by the cyanobacteria.

  11. Analisis sistem irigasi hidroponik NFT (nutrient film technique) pada tanaman budidaya tanaman selada (Lactuca sativa var crispa L.)

    OpenAIRE

    Sibarani, Sahat Muhtar

    2012-01-01

    Nutrient Film Technique (I\\FFT) is a new technological in hidroponics. In this system, a part of root deep on the water have fertilizers and other part upon the water which sirculating above 24 hours. The lining of the water is slight, about 3 mm, so its like film. The research of NFT irrigation was carried out to study on Electric Conductivity(EC) uniformity and pH of nutrient liquid as well as effectivity of gutters gradient application. The research was done with planting the plants in ...

  12. Nitrate content in dandelion (Taraxacum officinale) and lettuce (Lactuca sativa) from organic and conventional origin: intake assessment.

    Science.gov (United States)

    Gorenjak, Alenka Hmelak; Koležnik, Urška Rizman; Cencič, Avrelija

    2012-01-01

    To estimate the actual intake of nitrate by consumption of different lettuce varieties, 52 samples of lettuce of different origins and dandelion from 15 different areas of northeast Slovenia were analysed. For determination of actual nitrate content, a continuous flow method was used. The lowest nitrate content was detected in dandelion, with a mean value of 195 mg kg(-1) (ranging 47-487 mg kg(-1)). Nitrate content in lettuce of different origins ranged 85-3237 mg kg(-1), with a mean value of 1196 mg kg(-1). The mean nitrate content in organically cultivated lettuce was 890 mg kg(-1), which was considerably lower than the nitrate level in conventionally cultivated lettuce (1298 mg kg(-1)). Consumption of 100 g of dandelion would result in a maximal nitrate intake corresponding to 22% of the acceptable daily intake (ADI), with values up to seven times higher for lettuce.

  13. Retention of Microcystis aeruginosa and microcystin by salad lettuce (Lactuca sativa) after spray irrigation with water containing cyanobacteria.

    Science.gov (United States)

    Codd, G A; Metcalf, J S; Beattie, K A

    1999-08-01

    Colonies and single cells of Microcystis aeruginosa and the hepatotoxin microcystin were retained by salad lettuce after growth with spray irrigation water containing the microcystin-producing cyanobacteria. These findings are discussed in terms of crop spray irrigation with water containing cyanobacteria and potential human exposure to cyanobacterial toxins via plant foods grown in such circumstances.

  14. Liquid humus and microorganisms to promote the production of Lettuce (Lactuca sativa var. Crespa in hydroponic crop

    Directory of Open Access Journals (Sweden)

    Velasco José

    2016-11-01

    Full Text Available In an initial phase, a trial with growing hydroponic lettuce was installed, considering all the macro and micronutrients necessary and sufficient for growth, where treatments were applied with and without liquid humus, combining separately with inoculation of mycorrhiza and bacteria Bacillus type, observing that the significant effect by the individual use of the liquid humus is up to 50%. Subsequently, in a Phase II, different doses of only liquid humus with only mycorrhizae were evaluated, where applying of 8 L of pure liquid humus per 36 L of stock solution of hydroponics crop, the plants had the highest weight (40.7%, the highest altitude (39% and the longest (42% compared to the witness. Instead, the combination of liquid humus plus mycorrhizal is 6 L per 36 L of stock solution, which stimulated a further growth and weight of growing lettuce in hydroponics conditions. In general, the use of liquid humus decreased the production time from 60 to 52 days.

  15. A genetic analysis of the introgression process from cultivated lettuce (Lactuca sativa L.) to wild prickly lettuce (L. serriola L.)

    NARCIS (Netherlands)

    Uwimana, B.

    2011-01-01

    Many plant species can hybridise and produce fertile offspring. Hybridization between cultivated species and their wild relatives has raised concerns with regard to GM crops, as it constitutes a possible route along which the transgene could disperse from crops into related wild species, establish

  16. Effect of proline on biochemical and molecular mechanisms in lettuce (Lactuca sativa L.) exposed to UV-B radiation.

    Science.gov (United States)

    Aksakal, Ozkan; Tabay, Dilruba; Esringu, Aslıhan; Icoglu Aksakal, Feyza; Esim, Nevzat

    2017-02-15

    The purpose of the present study was to evaluate the role of proline (Pro) in relieving UV-B radiation-induced oxidative stress in lettuce. Lettuce seedlings were exposed to 3.3 W m -2 UV-B radiation for 12 h after pre-treatment sprayed with 20 mM Pro. The data for malondialdehyde (MDA), hydrogen peroxide (H 2 O 2 ), endogenous Pro level, the activities of antioxidant enzymes [superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), and peroxidase (POD)], total phenolic concentration, antioxidant capacity, expression of phenylalanine ammonia lyase (PAL), γ-tocopherol methyltransferase (γ-TMT) and proline dehydrogenase (ProDH) genes, phytohormone levels such as abscisic acid (ABA), gibberellic acid (GA), indole acetic acid (IAA) and salicylic acid (SA), soluble sugars and organic acids were recorded. It was found that Pro alleviated the oxidative damage in the seedlings of lettuce as demonstrated by lower lipid peroxidation and H 2 O 2 content, increasing the endogenous Pro level, the activity of antioxidant enzymes, total phenolic concentration and the antioxidant capacity. Additionally, it was revealed that exogenous application of Pro enhanced the levels of GA, IAA, the concentrations of soluble sugars and organic acids and expressions of PAL, γ-TMT and ProDH genes as compared to the control. The results obtained in this study suggest that pre-treatment with exogenous Pro provides important contributions to the increase in the UV-B tolerance of lettuce by regulating the biochemical mechanisms of UV-B response.

  17. Assessment of the impact of Aluminum on germination, early growth and free proline content in Lactuca sativa L.

    Science.gov (United States)

    Silva, Patrícia; Matos, Manuela

    2016-09-01

    Aluminum (Al) toxicity is a major problem in crop production on acid soils. The use of industrial or municipal wastewaters, which may be contaminated with metals, for irrigation in agriculture is common over the world. This action can increase the concentration of these agents in the soil and decrease crops yields. In order to evaluate the toxicological effects of recommended Al levels in irrigation water, under acidic conditions, on lettuce, seeds of two cultivars ("cv Reine de Mai" and "cv White Boston") were exposed to five different Al concentrations (0, 0.05, 0.5, 5 and 20mg/L) and germination percentage, root and shoot lengths were measured. Also, the germination rate and the vigor index were calculated, and the proline content was estimated for all concentrations. Results showed that seed germination was not negatively affected by Al, but the germination rate decreased in both cultivars. For the other factors analyzed, with the exception of 20mg/L concentration for "cv White Boston", Al induced, in general, negative effects including the content of proline that increased in the seeds that were exposed to this metal. The "cv Reine de Mai" was more sensitive for the analyzed concentrations than the other cultivar.. The results indicated that even recommended Al concentrations for irrigation, under acidic conditions, can interfere negatively in seed germination and seedling establishment and possibly with crop production. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Effects of glucose and ethylene on root hair initiation and elongation in lettuce (Lactuca sativa L.) seedlings.

    Science.gov (United States)

    Harigaya, Wakana; Takahashi, Hidenori

    2017-12-13

    Root hair formation occurs in lettuce seedlings after transfer to an acidic medium (pH 4.0). This process requires cortical microtubule (CMT) randomization in root epidermal cells and the plant hormone ethylene. We investigated the interaction between ethylene and glucose, a new signaling molecule in plants, in lettuce root development, with an emphasis on root hair formation. Dark-grown seedlings were used to exclude the effect of photosynthetically produced glucose. In the dark, neither root hair formation nor the CMT randomization preceding it occurred, even after transfer to the acidic medium (pH 4.0). Adding 1-aminocyclopropane-1-carboxylic-acid (ACC) to the medium rescued the induction, while adding glucose did not. Although CMT randomization occurred when glucose was applied together with ACC, it was somewhat suppressed compared to that in ACC-treated seedlings. This was not due to a decrease in the speed of randomization, but due to lowering of the maximum degree of randomization. Despite the negative effect of glucose on ACC-induced CMT randomization, the density and length of ACC-induced root hairs increased when glucose was also added. The hair-cell length of the ACC-treated seedlings was comparable to that in the combined-treatment seedlings, indicating that the increase in hair density caused by glucose results from an increase in the root hair number. Furthermore, quantitative RT-PCR revealed that glucose suppressed ethylene signaling. These results suggest that glucose has a negative and positive effect on the earlier and later stages of root hair formation, respectively, and that the promotion of the initiation and elongation of root hairs by glucose may be mediated in an ethylene-independent manner.

  19. Randomization of cortical microtubules in root epidermal cells induces root hair initiation in lettuce (Lactuca sativa L.) seedlings.

    Science.gov (United States)

    Takahashi, Hidenori; Hirota, Kayoko; Kawahara, Aiko; Hayakawa, Erika; Inoue, Yasunori

    2003-03-01

    Root hair formation is induced when lettuce seedlings are transferred from liquid medium at pH 6.0 to fresh medium at pH 4.0. If seedlings are transferred to pH 6.0, no root hairs are formed. We investigated the role of microtubules in this low pH-induced root hair initiation in lettuce. At the hair-forming zone in root epidermal cells, microtubules were perpendicular to the longitudinal axis of the cell just after pre-culture. This arrangement became disordered as early as 5 min after transfer to pH 4.0, and became random by 30 min later. At pH 4.0, the randomization extended to the entire hair-forming zone of seedlings; at pH 6.0, however, randomization did not occur and transverse microtubules were maintained. When seedlings at pH 6.0 were treated with microtubule-depolymerizing drugs, root hairs were formed. In contrast, when a microtubule-stabilizing drug, taxol, was added to the medium, no root hairs formed, even at pH 4.0. These results suggest that the transverse cortical microtubules inhibit root hair formation, and that their destruction is necessary for initiation. Furthermore, the microfilament-disrupting drugs cytochalasin B and latrunculin B inhibited root hair initiation, suggesting that actin filaments are necessary for root hair initiation.

  20. Effects of sodium nitroprusside (SNP) pretreatment on UV-B stress tolerance in lettuce (Lactuca sativa L.) seedlings.

    Science.gov (United States)

    Esringu, Aslıhan; Aksakal, Ozkan; Tabay, Dilruba; Kara, Ayse Aydan

    2016-01-01

    Ultraviolet-B (UV-B) radiation is one of the most important abiotic stress factors that could influence plant growth, development, and productivity. Nitric oxide (NO) is an important plant growth regulator involved in a wide variety of physiological processes. In the present study, the possibility of enhancing UV-B stress tolerance of lettuce seedlings by the exogenous application of sodium nitroprusside (SNP) was investigated. UV-B radiation increased the activities of superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), peroxidase (POD) and total phenolic concentrations, antioxidant capacity, and expression of phenylalanine ammonia lyase (PAL) gene in seedlings, but the combination of SNP pretreatment and UV-B enhanced antioxidant enzyme activities, total phenolic concentrations, antioxidant capacity, and PAL gene expression even more. Moreover, UV-B radiation significantly inhibited chlorophylls, carotenoid, gibberellic acid (GA), and indole-3-acetic acid (IAA) contents and increased the contents of abscisic acid (ABA), salicylic acid (SA), malondialdehyde (MDA), hydrogen peroxide (H2O2), and superoxide radical (O2•(-)) in lettuce seedlings. When SNP pretreatment was combined with the UV-B radiation, we observed alleviated chlorophylls, carotenoid, GA, and IAA inhibition and decreased content of ABA, SA, MDA, H2O2, and O2•(-) in comparison to non-pretreated stressed seedlings.

  1. High-throughput growth prediction for Lactuca sativa L. seedlings using chlorophyll fluorescence in a plant factory with artificial lighting

    Directory of Open Access Journals (Sweden)

    Shogo eMoriyuki

    2016-03-01

    Full Text Available Poorly grown plants that result from differences in individuals lead to large profit losses for plant factories that use large electric power sources for cultivation. Thus, identifying and culling the low-grade seedlings at an early stage, using so-called seedling diagnosis technology, plays an important role in avoiding large losses in plant factories. In this study, we developed a high-throughput diagnosis system using the measurement of chlorophyll fluorescence (CF in a commercial large-scale plant factory, which produces about 5,000 lettuce plants every day. At an early stage (6 days after sowing, a CF image of 6,000 seedlings was captured every 4 hours on the final greening day by a high-sensitivity CCD camera and an automatic transferring machine, and biological indices were extracted. Using machine learning, plant growth can be predicted with a high degree of accuracy based on biological indices including leaf size, amount of CF, and circadian rhythms in CF. Growth prediction was improved by addition of temporal information on CF. The present data also provide new insights into the relationships between growth and temporal information regulated by the inherent biological clock.

  2. Efectividad del agua electrolizada oxidadora (EO en la inactivación de Listeria monocytogenes en lechuga (Lactuca sativa L.

    Directory of Open Access Journals (Sweden)

    Casadiego P

    2004-12-01

    Full Text Available Se evaluó la efectividad del agua electrolizada oxidadora (EO en la inactivación de Listeria monocytogenes enlechuga; para ello se construyó una celda electrolítica para la producción de agua EO a partir de una soluciónde NaCl al 5%, con una concentración de cloro residual de 29 partes por millón (ppm y pH 2.83. Cinco de las10 cepas de Listeria monocytogenes mas resistentes a la acción del hipoclorito de sodio, fueron obtenidas apartir de muestras de pollo procesado e inoculadas en 9 ml de agua EO o 9 ml de agua desionizada estéril(control e incubadas a 15°C durante 5, 10, 15 y 20 minutos. La población se determinó por recuento en placaen agar Columbia, obteniéndose una reducción de 6.6 UL a los 5 minutos de exposición. Las cepas seleccionadasfueron utilizadas como suspensión mixta (9.56 UL, 109 UFC/ml para inocular 35 lechugas por el método deinmersión. Se sumergieron 6.25 g de cada lechuga en 375 ml de agua EO o agua destilada (control a 15 °Cdurante 5 minutos. La población promedio de Listeria monocytogenes después del tratamiento con agua EO ycon agua destilada, se redujo en 3.92 y 2.46 UL respectivamente. Se demostró que el agua EO tiene un efectobactericida estadísticamente significativo (p=0.00001. Para mejorar el efecto del agua EO sobre L .monocytogenes en lechuga, se evaluó su efectividad en combinación con ácido acético al 6% (vinagre.Reducción de la población en 5.49 UL demuestran que hay un efecto sinergista de ambos agentes antimicrobianossobre la viabilidad de las células de L. monocytogenes.

  3. Growth and Tissue Elemental Composition Response of Butterhead Lettuce (Lactuca sativa, cv. Flandria) to Hydroponic and Aquaponic Conditions

    OpenAIRE

    Tyler S. Anderson; David de Villiers; Michael B. Timmons

    2017-01-01

    The primary objective of this research was to compare lettuce performance under conventional hydroponics at pH 5.8 (referred to as H5), hydroponics at pH 7.0 (referred to as H7), and recirculated aquaponic water at pH 7.0 (referred to as A7). Aquaponic nutrients were supplied by continuously recirculating water between a fish rearing system (recirculating aquaculture system or RAS) and the lettuce growing system (with the sole addition being chelated iron). This paper builds upon our previous...

  4. Growth and Tissue Elemental Composition Response of Butterhead Lettuce (Lactuca sativa, cv. Flandria to Hydroponic and Aquaponic Conditions

    Directory of Open Access Journals (Sweden)

    Tyler S. Anderson

    2017-07-01

    Full Text Available The primary objective of this research was to compare lettuce performance under conventional hydroponics at pH 5.8 (referred to as H5, hydroponics at pH 7.0 (referred to as H7, and recirculated aquaponic water at pH 7.0 (referred to as A7. Aquaponic nutrients were supplied by continuously recirculating water between a fish rearing system (recirculating aquaculture system or RAS and the lettuce growing system (with the sole addition being chelated iron. This paper builds upon our previous research where we found that H7 produced 26% less shoot fresh weight (FW growth than H5 and an 18% reduction in dry weight (DW. In this research, we also evaluated the inorganic hydroponics nutrient solution at pH 7.0 (H7 to provide continuity between experiments and to isolate the pH effect. The A7 plant biomass responses were not different from H5 in all biomass response categories. H7 was different from H5 in shoot FW, DW, and DW/FW, as well as root FW and DW. H7 was different from the A7 in shoot FW, DW/FW, and root DW. There were no tissue elemental differences between H5 and H7 except Cu. The Ca and Na contents differed between H5 and A7, while the microelements Mn, Mo, and Zn differed. Generally, the elemental tissue differences between treatments were proportional to the differences for the same elements in the nutrient solutions. Aquaponic systems are often viewed to be more complicated and more risky because two complex systems are being joined (hydroponics plus RAS. However, the aquaponics system proved to be surprisingly simple to manage in daily operations. Our data suggested that the aquaponics system (A7, which was operated at a higher pH 7.0, was able to offset any negative biomass and elemental effects that occurred in the inorganic hydroponic pH 7.0 treatment (H7 from its increased pH and less optimized nutrient solution elemental concentrations.

  5. Perchlorate, Nitrate, and Iodine Uptake and Distribution in Lettuce (Lactuca sativa L.) and Potential Impact on Background Levels in Humans

    NARCIS (Netherlands)

    Voogt, W.; Jackson, A.

    2010-01-01

    Much focus has been placed on the impact of exposure to perchlorate (ClO4-) from drinking water. Recently, it has become more apparent that a significant percentage of the total ClO4- exposure may be due to ingestion of food. Most studies have only evaluated the uptake and distribution of ClO4- by

  6. Experiencia de producción de lechuga americana (Lactuca sativa hidropónica, tipo NFT

    Directory of Open Access Journals (Sweden)

    Laura Brenes-Peralta

    2014-06-01

    En el Centro de Prácticas Docentes e Investigación Agropecuaria de la Escuela de Agronegocios del Instituto Tecnológico de Costa Rica (TEC se cuenta, actualmente, con un sistema de este tipo NFT donde estableció una actividad de fortalecimiento que ha resultado en la observación de ciertas características a partir de la experiencia generada, de la cual se espera fomentar el uso de la hidroponía, así como divulgar información técnica y de buenas prácticas en este tipo de cultivo entre usuarios interesados.

  7. Filth fly transmission of Escherichia coli O157:H7 and Salmonella enterica to lettuce, Lactuca sativa

    Science.gov (United States)

    Filth flies have been implicated in the dispersal of human disease pathogens; however, fly transmission parameters of human pathogens to plants are largely undescribed. The capacity of the black blow fly, Phormia regina, to acquire and subsequently release bacteria onto baby lettuce leaves was comp...

  8. Rapid Transient Production of a Monoclonal Antibody Neutralizing the Porcine Epidemic Diarrhea Virus (PEDV) in Nicotiana benthamiana and Lactuca sativa.

    Science.gov (United States)

    Rattanapisit, Kaewta; Srijangwad, Anchalee; Chuanasa, Taksina; Sukrong, Suchada; Tantituvanont, Angkana; Mason, Hugh S; Nilubol, Dachrit; Phoolcharoen, Waranyoo

    2017-12-01

    Porcine epidemic diarrhea virus (PEDV) causes acute diarrhea, vomiting, dehydration, weight loss, and high mortality rate in neonatal piglets. Porcine epidemic diarrhea (PED) has been reported in Europe, America, and Asia including Thailand. The disease causes substantial losses to the swine industry in many countries. Presently, there is no effective PEDV vaccine available. In this study, we developed a plant-produced monoclonal antibody (mAb) 2C10 as a prophylactic candidate to prevent the PEDV infection. Recently, plant expression systems have gained interest as an alternative for the production of antibodies because of many advantages, such as low production cost, lack of human and animal pathogen, large scalability, etc. The 2C10 mAb was transiently expressed in Nicotiana benthamiana and lettuce using geminiviral vector. After purification by protein A affinity chromatography, the antibody was tested for the binding and neutralizing activity against PEDV. Our result showed that the plant produced 2C10 mAb can bind to the virus and also inhibit PEDV infection in vitro . These results show excellent potential for a plant-expressed 2C10 as a PEDV prophylaxis and a diagnostic for PEDV infection. Georg Thieme Verlag KG Stuttgart · New York.

  9. Treated wastewater phytotoxicity assessment using Lactuca sativa: Focus on germination and root elongation test parameters.

    Science.gov (United States)

    Priac, Anne; Badot, Pierre-Marie; Crini, Grégorio

    2017-03-01

    Sensitive and simple ecotoxicological bioassays like seed germination and root elongation tests are commonly used to evaluate the phytotoxicity of waste and industrial discharge waters. Although the tests are performed following national and international standards, various parameters such as the number of seeds per dish, the test duration or the type of support used remain variable. To be able to make a correct comparison of results from different studies, it is crucial to know which parameter(s) could affect ecotoxicological diagnosis. We tested four different control waters and three seed densities. No significant differences on either germination rate or root elongation endpoints were shown. Nevertheless, we found that the four lettuce cultivars (Appia, batavia dorée de printemps, grosse blonde paresseuse, and Kinemontepas) showed significantly different responses when watered with the same and different metal-loaded industrial discharge water. From the comparison, it is clear that a differential sensitivity scale occurs among not just species but cultivars. Copyright © 2017 Académie des sciences. Published by Elsevier Masson SAS. All rights reserved.

  10. Effect of supplemental ultraviolet radiation on the concentration of phytonutrients in green and red leaf lettuce (Lactuca sativa) cultivars

    Science.gov (United States)

    Britz, Steven; Caldwell, Charles; Mirecki, Roman; Slusser, James; Gao, Wei

    2005-08-01

    Eight cultivars each of red and green leaf lettuce were raised in a greenhouse with supplemental UV radiation, either UV-A (wavelengths greater than ca. 315 nm) or UV-A+UV-B (wavelengths greater than ca. 290 nm; 6.4 kJ m-2 daily biologically effective UV-B), or no supplemental UV (controls). Several phytonutrients were analyzed in leaf flours to identify lines with large differences in composition and response to UV-B. Red leaf lettuce had higher levels of phenolic acid esters, flavonols and anthocyanins than green lines. Both green and red lines exposed to UV-B for 9 days showed 2-3-fold increases in flavonoids compared to controls, but only 45% increases in phenolic acid esters, suggesting these compounds may be regulated by different mechanisms. There were large differences between cultivars in levels of phenolic compounds under control conditions and also large differences in UV-B effects. Among red varieties, cv. Galactic was notable for high levels of phenolics and a large response to UV-B. Among green varieties, cvs. Black-Seeded Simpson and Simpson Elite had large increases in phenolics with UV-B exposure. Photosynthetic pigments were also analyzed. Green leaf lettuce had high levels of pheophytin, a chlorophyll degradation product. Total chlorophylls (including pheophytin) were much lower in green compared to red varieties. Lutein, a carotenoid, was similar for green and red lines. Total chlorophylls and lutein increased 2-fold under supplemental UV-B in green lines but decreased slightly under UV-B in red lines. Lettuce appears to be a valuable crop to use to study phytochemical-environment interactions.

  11. Expression analysis of polyphenol oxidase isozymes by active staining method and tissue browning of head lettuce (Lactuca sativa L.).

    Science.gov (United States)

    Noda, Takahiro; Iimure, Kazuhiko; Okamoto, Shunsuke; Saito, Akira

    2017-08-01

    Browning of plant tissue is generally considered attributable to enzymatic oxidation by polyphenol oxidase (PPO). Electrophoresis followed by activity staining has been used as an effective procedure to visually detect and isolate isozymes; however, it has not been applied for examination of various PPO isozymes in lettuce. Our study demonstrated that different lettuce PPO isozymes could be detected at different pH in active staining, and multiple isozymes were detected only under alkaline conditions. As a result, we concluded that activity staining with approximately pH 8 enabled to detect various PPO isozymes in lettuce. By expression analysis of the PPO isozymes after wounding, PPO isozymes that correlated with time-course of tissue browning were detected. The wound-induced PPO may play a key role in enzymatic browning.

  12. Transcriptome Profiling of Caco-2 Cancer Cell Line following Treatment with Extracts from Iodine-Biofortified Lettuce (Lactuca sativa L..

    Directory of Open Access Journals (Sweden)

    Aneta A Koronowicz

    Full Text Available Although iodization of salt is the most common method used to obtain iodine-enriched food, iodine deficiency disorders are still a global health problem and profoundly affect the quality of human life. Iodine is required for the synthesis of thyroid hormones, which are crucial regulators of human metabolism, cell growth, proliferation, apoptosis and have been reported to be involved in carcinogenesis. In this study, for the first time, we evaluated the effect of iodine-biofortified lettuce on transcriptomic profile of Caco-2 cancer cell line by applying the Whole Human Genome Microarray assay. We showed 1326 differentially expressed Caco-2 transcripts after treatment with iodine-biofortified (BFL and non-fortified (NFL lettuce extracts. We analysed pathways, molecular functions, biological processes and protein classes based on comparison between BFL and NFL specific genes. Iodine, which was expected to act as a free ion (KI-NFL or at least in part to be incorporated into lettuce macromolecules (BFL, differently regulated pathways of numerous transcription factors leading to different cellular effects. In this study we showed the inhibition of Caco-2 cells proliferation after treatment with BFL, but not potassium iodide (KI, and BFL-mediated induction of mitochondrial apoptosis and/or cell differentiation. Our results showed that iodine-biofortified plants can be effectively used by cells as an alternative source of this trace element. Moreover, the observed differences in action of both iodine sources may suggest a potential of BFL in cancer treatment.

  13. Marine biomass research in Florida. [Gracilaria tikvahiae, Ulva Lactuca

    Energy Technology Data Exchange (ETDEWEB)

    Ryther, J.H.

    1983-01-01

    The red alga Gracilaria tikvahiae may be grown outdoors year-round in central Florida with yields averaging 35.5 g dry weight/sq. m/day, greater than the most productive terrestrial plants. This occurs when the plants are grown in suspended culture, with vigorous aeration and an exchange of 25 or more culture volumes of enriched seawater per day. A culture system was designed in which Gracilaria, stocked at a density of 2 kg wet weight/sq.m, grows to double its biomass in one to two weeks; it is then harvested to its starting density, and anaerobically digested to methane. The biomass is soaked for 6 hours in the digester residue, storing enough nutrients for two week's growth in unenriched seawater. The methane is combusted for energy and the waste gas is fed to the culture to provide mixing of CO/sub 2/ eliminating the need for aeration and seawater exchange. The green alga Ulva lactuca, unlike Gracilaria, uses bicarbonate as a photosynthesis carbon source, and can be grown at high pH, with little or no free CO/sub 2/. It can therefore produce higher yields than Gracilaria in low water exchange conditions. It is also more efficiently converted to methane than is Gracilaria, but cannot tolerate Florida's summer temperatures so cannot be grown year-round. Attempts are being made to locate or produce through selective breeding, a high-temperature tolerant strain of Ulva. 21 references.

  14. Subsequent influences of feeding intact green seaweed Ulva lactuca to growing lambs on the seminal and testicular characteristics in rams.

    Science.gov (United States)

    Samara, E M; Okab, A B; Abdoun, K A; El-Waziry, A M; Al-Haidary, A A

    2013-12-01

    The present experiment was designed to investigate the subsequent influences of supplementing different levels of intact green seaweed Ulva lactuca (0%, 3%, and 5% DM) to growing sexually immature lambs during the growth period (74 d) on the seminal and testicular characteristics of sexually mature rams. Ulva lactuca was manually collected, adequately prepared, and then incorporated into lambs' diets. Eighteen male 3-mo-old lambs of the Awassi breed with a mean BW of 22.57 kg (SD = 1.08) were randomly assigned into treatments. The obtained results indicate that offering Ulva lactuca at the level of 3% or 5% DM to lambs during the growth period had no subsequent impacts (P > 0.05) on liver and kidney functions as well as blood water balance in rams, thereby suggesting that Ulva lactuca can be safely supplemented to lambs during growing. However, our findings point out that feeding a lamb diet supplemented with intact Ulva lactuca failed to demonstrate any subsequent benefit (P > 0.05) on the growth performance, thermoregulatory responses, and plasma oxidative status in rams. Above all, it was clearly evident that supplementing intact Ulva lactuca to lambs had demonstrated subsequent negative influences (P Ulva lactuca during the growth period compared to control rams. The deleterious impacts of feeding intact Ulva lactuca on spermatogenesis and germ cell loss were proven to be attributed to the dysfunction of Sertoli cells. Collectively, these results provide novel insights on the subsequent influences of dietary supplementation of intact Ulva lactuca to lambs. The consistent evidence of profound negative impacts on seminal and testicular characteristics as well as the resulting data of no improvement of subsequent growth, thermoregulation, and plasma oxidative status in rams prompts us to tentatively recommend the avoidance of feeding intact Ulva lactuca to lambs.

  15. A taxonomic revision of the genus lactuca L. (cicihorieae- asteraceae) from Pakistan and Kashmir

    International Nuclear Information System (INIS)

    Qaiser, M.; Bano, R.

    2011-01-01

    The genus Lactuca L. of the tribe Cichorieae-Asteraceae is taxonomically revised from Pakistan and Kashmir. The revision is based on study of large number of herbarium specimens. In few cases plants have also been studied in their natural habitat. A total of 13 species are recognized from Pakistan and Kashmir including 1 new species i.e. Lactuca erostrata Roohi Bano and Qaiser. A new combination Lactuca orientalis subsp. nuristanica (Podlech) Roohi Bano and Qaiser is also proposed. All the taxa valid or synonyms have been typified with the help of type specimens and literature. Key to the species along with detailed morphological description and ecological notes of each taxon are also given. (author)

  16. Cobertura morta e adubação orgânica na produção de alface e supressão de plantas daninhas

    Directory of Open Access Journals (Sweden)

    Izabel Cristina Pereira Vaz Ferreira

    2013-08-01

    Full Text Available Objetivou-se, neste trabalho, avaliar os efeitos da cobertura do solo e da adubação orgânica sobre a temperatura e a umidade do solo, a incidência de plantas daninhas e a produtividade da alface. O delineamento experimental utilizado foi de blocos casualizados, em esquema fatorial (3 x 3, em que o primeiro fator corresponde aos tipos de cobertura morta (capim tifton, capim napier e ausência de cobertura e, o segundo, aos adubos (esterco bovino, esterco de galinhas e ausência de adubação. Analisaram-se as variáveis temperatura e umidade do solo, o número de folhas produzidas pela alface, as massas de matéria fresca e seca da parte aérea, das plantas de alface e daninhas, e o levantamento fitossociológico das plantas infestantes. As plantas adubadas com esterco de galinhas apresentaram massas de matéria fresca e seca superiores às das plantas não adubadas. A cobertura morta com capim tifton proporcionou aumento da massa de matéria seca das plantas de alface, o que pode estar relacionado com a menor temperatura dos canteiros que receberam esse material como cobertura. Commelina benghalensis foi a planta infestante mais importante no cultivo orgânico de alface. A aplicação de adubos orgânicos e a cobertura morta com capins não foram capazes de suprimir plantas daninhas e manter a umidade do solo, em áreas de cultivo de alface.

  17. Agronomic and economic viability of intercropping onion and lettuce Viabilidade agroeconômica do cultivo consorciado de cebola e alface

    Directory of Open Access Journals (Sweden)

    Wagner F da Mota

    2012-06-01

    Full Text Available The study aimed to evaluate the agronomic and economic performance of intercropping onion and lettuce on four plant densities of each species. The experiment was set up in completely randomized blocks, with four replications and treatments arranged in a 4 x 4 factorial. Treatments resulted from a combination of four (100, 80, 60, and 40% of recommended plant densities in monoculture plant densities for both lettuce and onion. Intercropping did not affect the agronomic performance of onion or lettuce. Higher plant densities (100% for both vegetables resulted in higher lettuce and onion yields. The best economic results were observed using (a onion at 80% of plant density combined with lettuce at 40 and 100% and (b onion at 100% and lettuce at all densities (40 to 100%.O trabalho teve como objetivos avaliar o desempenho agroeconômico do consórcio de cebola e alface em quatro densidades populacionais de cada espécie. O delineamento experimental foi blocos casualizados, com quatro repetições, sendo os tratamentos arranjados em esquema fatorial 4 x 4. Os tratamentos resultaram da combinação de quatro populações (100, 80, 60 e 40% das populações recomendadas nos cultivos solteiros tanto de alface, quanto de cebola. O consórcio não afetou o desempenho agronômico da cebola, tampouco o da alface, e a densidade populacional de 100% para ambas as hortaliças propiciou maior produtividade de cebola e de alface. Do ponto de vista econômico, os melhores resultados foram observados nos consórcios (a cebola a 80% da densidade de plantas em consórcio com alface a 40 e 100% e (b cebola a 100% com alface em qualquer densidade (40 a 100%.

  18. Resíduo da produção de Pochonia chlamydosporia no desenvolvimento de mudas e plantas de alface

    OpenAIRE

    Viggiano,José Ricardo; Freitas,Leandro Grassi de; Ferreira,Paulo Afonso

    2012-01-01

    O objetivo deste trabalho foi avaliar o efeito de subproduto do processo de produção de Pochonia chlamydosporia var. chlamydosporia no desenvolvimento de mudas e plantas de alface. Esse subproduto, um resíduo constituído de arroz que continha propágulos do fungo, foi adicionado em diferentes concentrações (0, 2 e 4% volume de resíduo:volume de substrato) a três tipos de substratos para mudas (formulado, comercial e fibra de coco). Sementes de alface foram semeadas em bandejas de isopor que co...

  19. Produção de alface e cenoura em cultivo solteiro e consorciado com manjericão e hortelã.

    OpenAIRE

    Maia, Janini Tatiane Lima Souza; Guilherme, Denilson Oliveira; Paulino, Marney Aparecida de Oliveira; Barbosa, Flávia Silva; Fernandes, Rodrigo Carvalho; Maio, Marck Morais; Valadares, Samuel Vasconcelos; Costa, Cândido Alves da; Martins, Ernane Ronie

    2008-01-01

    O objetivo do presente trabalho foi avaliar o consórcio das hortaliças alface e cenoura com as plantas medicinais manjericão e hortelã. O experimento foi realizado em uma propriedade localizada na região da Bacia do Alto Pacuí, Montes Claros – MG. Foi utilizado o delineamento em blocos casualizados com sete tratamentos e três repetições. Os tratamentos consistiram em: alface solteira e em consórcio com manjericão e hortelã, cenoura solteira e consorciada com manjericão e hortelã, e consórcio ...

  20. Produtividade de alface e rúcula, em sistema consorciado, sob adubação orgânica e mineral

    OpenAIRE

    Oliveira,Eliane Q de; Souza,Rovilson J de; Cruz,Maria do Céu M da; Marques,Virna B; França,André C

    2010-01-01

    Foram realizados dois experimentos em Lavras-MG, nos meses de abril a setembro de 2006. Para cada experimento, utilizou-se o delineamento de blocos completos casualizados, com cinco tratamentos e quatro repetições. Os tratamentos consistiram de quatro arranjos espaciais entre as culturas da alface (A) e rúcula (R), plantadas em fileiras alternadas 1A:1R; fileiras duplas alternadas 2A:2R; fileiras triplas alternadas 3A:3R e quatro fileiras alternadas 4A:4R e, alface e rúcula em cultivo solteir...

  1. Avaliação de cultivares de alface adubadas com silicato de cálcio em casa-de-vegetação.

    OpenAIRE

    FERREIRA, R. L. F.; SOUZA, R. J. de; CARVALHO, J. G. de; ARAÚJO NETO, S. E. de; MENDONÇA, V.; WADT, P. G. S.

    2011-01-01

    O experimento foi conduzido no Departamento de Ciência do Solo da Universidade Federal de Lavras - UFLA, no período de junho a agosto de 2002. Objetivou-se avaliar a produtividade, o estado nutricional e a qualidade (classe de tamanho) de cultivares de alface cultivadas com doses de silicato de cálcio em vasos sob casa-de-vegetação. O delineamento experimental foi em blocos casualizados, com quatro repetições, com 1 planta/vaso, em esquema fatorial 3 x 4 + 3, sendo três cultivares de alface (...

  2. Reposição de nutrientes durante três cultivos de alface em hidroponia

    Directory of Open Access Journals (Sweden)

    Backes Fernanda Alice A.L.

    2003-01-01

    Full Text Available O experimento foi realizado em estufa plástica na UFSM, de agosto a novembro/99. Avaliou-se cinco formas de reposição de nutrientes na solução nutritiva com base na condutividade elétrica (CE, no sistema 'NFT' (Nutrient Film Technique e duas cultivares de alface: Regina e Deisy, cultivadas em bancadas de sustentação formadas por telhas de fibro-cimento revestidas com tinta betuminosa Neutrolâ. Foram dispostas 14 plantas por canal para cada repetição e uma cultivar em cada três canais, totalizando 84 plantas por bancada de produção. Comparou-se a eficiência de métodos de reposição de nutrientes na produção de alface, assim como a utilização da mesma solução, com reposição de nutrientes, durante três cultivos consecutivos. O delineamento experimental foi de blocos casualizados, com três repetições, em esquema fatorial 5x2. Os resultados demonstraram que o desempenho das cultivares avaliadas não foi influenciado pelos métodos de reposição de nutrientes. A ausência de reposição de nutrientes na solução nutritiva, durante um cultivo, permitiu maior produtividade da cultura, não se recomendando a reposição quando o objetivo for renovar a solução ao final do cultivo. As formas de reposição de nutrientes na solução nutritiva, durante o primeiro e segundo cultivos, não alteraram a produtividade da cultura em relação à renovação completa da solução nutritiva ao final do cultivo hidropônico. Para a reutilização de solução nutritiva, recomenda-se a reposição de nutrientes sempre que a CE diminuir 50% da inicial, possibilitando a produção por pelo menos três cultivos.

  3. Envelhecimento acelerado em sementes de alface Accelerated aging in lettuce seeds

    Directory of Open Access Journals (Sweden)

    Rafael Marani Barbosa

    2011-11-01

    Full Text Available Objetivou-se adequar a metodologia do teste de envelhecimento acelerado para avaliação do potencial fisiológico de sementes de quatro lotes dos genótipos de alface 'Babá de verão', 'Tainá' e 'Vera', aplicando-se o método tradicional e com o uso de solução saturada de NaCl. Para tal, as sementes foram submetidas à determinação do teor de água, testes de germinação e vigor (primeira contagem, condutividade elétrica, emergência em bandeja, índice de velocidade de emergência incluindo o teste de envelhecimento acelerado, conduzido nos períodos de 24, 48, e 72 horas, a 41°C com e sem solução saturada de NaCl. O experimento foi conduzido em delineamento inteiramente casualizado com quatro repetições. Os procedimentos tradicional e com o uso da solução saturada de NaCl por 72 horas foram sensíveis em estratificar os lotes em níveis de vigor, além de estarem de acordo com os demais testes utilizados. Portanto, o envelhecimento acelerado de sementes de alface deve ser feito utilizando o período de 72 horas, podendo ser realizado tanto pelo método tradicional quanto pelo método da solução saturada de NaCl.The objective was to adapt the methodology of the accelerated aging test to evaluate the physiological potential of seeds of four lots of lettuce genotypes 'Babá de verão', 'Tainá' and 'Vera' applying the traditional method and using a saturated NaCl solution. So, the seeds were subjected to determination of water content, seed germination and vigor (first count, electrical conductivity, speed emergency index, emergency tray including the accelerated aging test conducted in periods of 24, 48, 72 hours at 41°C with and without saturated solution of NaCl. The experiment was conducted in a randomized design with four replications. The accelerated aging traditional and saturated solution of NaCl by 72h was more sensitive to stratify the lots in vigor levels. Therefore, accelerated aging of seeds of lettuce should be

  4. Diferentes cores de armadilhas adesivas na cultura da alface hidropônica

    Directory of Open Access Journals (Sweden)

    Regina da Silva Borba

    2014-07-01

    Full Text Available O trabalho teve como objetivo avaliar qual a cor mais atrativa para os insetos-praga mosca-minadora (Liriomyza trifolii e tripes (Thrips tabaci. O experimento foi desenvolvido na empresa BioPlanta Hidroponia situada em Ivoti/RS, no período de 07/02/2012 a 03/04/2012, na cultura da alface, variedade Mouse, cultivada em ambiente protegido. Foram confeccionadas em cartelas plásticas de 10 x 15 cm, armadilhas nas cores amarela, branco, azul e verde, tendo sua superfície coberta por cola entomológica. Foram dispostas 12 repetições aleatórias de cada cor, sendo que cada mesa de cultivo hidropônico recebeu quatro cartelas de cores distintas. Foi feita a contagem dos insetos coletados semanalmente durante 9 semanas e os dados analisados pelo Programa Winstat 2.0 e as médias comparadas pelo Teste de Duncan, em nível de 5% de probabilidade de erro. As armadilhas de coloração amarela se mostraram mais atrativas para L. trifolii, enquanto a coloração azul se mostrou mais atrativa para T. tabaci.

  5. Differential growth response of Ulva lactuca to ammonium and nitrate assimilation

    DEFF Research Database (Denmark)

    Ale, Marcel Tutor; Mikkelsen, Jørn Dalgaard; Meyer, Anne S

    2011-01-01

    Controlled cultivation of marine macroalgal biomass such as Ulva species, notably Ulva lactuca, is currently studied for production of biofuels or functional food ingredients. In a eutrophic environment, this macrophyte is exposed to varying types of nutrient supply, including different and fluct...

  6. Species relationships in Lactuca S.L. (Lactuceae, Asteraceae) inferred from AFLP fingerprints

    NARCIS (Netherlands)

    Koopman, W.J.M.; Zevenbergen, M.J.; Berg, van den R.G.

    2001-01-01

    An AFLP data set comprising 95 accessions from 20 species of Lactuca s.l. (sensu lato) and related genera was generated using the primer combinations E35/M48 and E35/M49. In phenetic analyses of a data subset, clustering with UPGMA based on Jaccard's similarity coefficient resulted in the highest

  7. Robustness and accuracy of Maxent niche modelling for Lactuca species distributions in light of collecting expeditions

    NARCIS (Netherlands)

    Cobben, M.M.P.; van Treuren, R.; Castañeda-Álvarez, N.P.; Khoury, C.K.; Kik, C.; van Hintum, T.J.L.

    2015-01-01

    Niche modelling software can be used to assess the probability of detecting a population of a plant species at a certain location. In this study, we used the distribution of the wild relatives of lettuce (Lactuca spp.) to investigate the applicability of Maxent species distribution models for

  8. Molecular biogeography of prickly lettuce (Lactuca serriola L.) shows traces of recent range expansion

    NARCIS (Netherlands)

    D'Andrea, L.; Meirmans, P.G.; van de Wiel, C.; Guadagnuolo, R.; van Treuren, R.; Kozlowski, G.; den Nijs, H.; Felber, F.

    2017-01-01

    Prickly lettuce (Lactuca serriola L., Asteraceae), a wild relative of cultivated lettuce, is an autogamous species which greatly expanded throughout Western and Northern Europe during the last 2 centuries. Here, we present a large-scale biogeographic genetic analysis performed on a dataset

  9. Effector identification in the lettuce downy mildew Bremia lactucae by massively parallel transcriptome sequencing

    NARCIS (Netherlands)

    Stassen, J.H.; Seidl, M.F.; Vergeer, P.W.; Nijman, I.J.; Snel, B.; Cuppen, E.; van den Ackerveken, G.

    2012-01-01

    Lettuce downy mildew (Bremia lactucae) is a rapidly adapting oomycete pathogen affecting commercial lettuce cultivation. Oomycetes are known to use a diverse arsenal of secreted proteins (effectors) to manipulate their hosts. Two classes of effector are known to be translocated by the host: the

  10. Production of acetone, butanol, and ethanol from biomass of the green seaweed Ulva lactuca

    NARCIS (Netherlands)

    Wal, van der H.; Sperber, B.L.H.M.; Houweling-Tan, G.B.N.; Bakker, R.R.C.; Brandenburg, W.A.; Lopez Contreras, Ana

    2013-01-01

    Green seaweed Ulva lactuca harvested from the North Sea near Zeeland (The Netherlands) was characterized as feedstock for acetone, ethanol and ethanol fermentation. Solubilization of over 90% of sugars was achieved by hot-water treatment followed by hydrolysis using commercial cellulases. A

  11. Removal of cadmium from aqueous solution using marine green algae, Ulva lactuca

    Directory of Open Access Journals (Sweden)

    Mohamed M. Ghoneim

    2014-01-01

    Full Text Available The present study aimed to evaluate the efficiency of marine algae for removal of metals from the aqueous solution. The green alga, Ulva lactuca, collected from the intertidal zone of the Suez Bay, northern part of the Red Sea was used to reduce cadmium levels from the aqueous solutions. The biosorption mechanisms of Cd2+ ions onto the algal tissues were examined using various analytical techniques: Fourier-transform infrared spectroscopy (FT-IR and Scanning electron microscopy (SEM. Results indicated that at the optimum pH value of 5.5; about 0.1 g of U. lactuca was enough to remove 99.2% of 10 mg L−1 Cd2+ at 30 °C in the aqueous solutions. The equilibrium data were well fitted with the Langmuir and Freundlich isotherms. The monolayer adsorption capacity was 29.1 mg g−1. The calculated RL and ‘n’ values have proved the favorability of cadmium adsorption onto U. lactuca. The desorption test revealed that HCl was the best for the elution of metals from the tested alga. In conclusion, the seaweed U. lactuca was the favorable alternative of cadmium removal from water.

  12. Evaluation of Nutritional Composition of The Dried Seaweed Ulva lactuca from Pameungpeuk Waters, Indonesia.

    Science.gov (United States)

    Rasyid, Abdullah

    2017-07-01

    The nutritional composition of the dried seaweed Ulva lactuca from Pameungpeuk waters, including proximate, vitamins, minerals, dietary fibre and heavy metal has been carried out. The objective of this present study is to know the nutritional composition of the dried seaweed U. lactuca for utilisation in human nutrition in the future. Results show that carbohydrate was the major component in the proximate analysis of U. lactuca in the present study. The carbohydrate content was 58.1%. Moisture, ash, protein and fat content were 16.9%, 11.2%, 13.6% and 0.19% respectively, while dietary fibre was 28.4%. The vitamin A content was examined in this study less than 0.5 IU/100 mg while vitamin B1 (thiamine) and vitamin B2 (riboflavin) were 4.87 mg/kg and 0.86 mg/kg respectively. The calcium content was 1828 mg/100 g higher than other minerals. The heavy metal content examined in this study were lower than the limit of the quality criteria applied to edible seaweeds sold in Indonesia. Based on the results of this study show that U. lactuca has potential to be developed as an alternative source of a healthy food for human in the future.

  13. USE OF ULVA LACTUCA TO DISTINGUISH PH DEPENDENT TOXICANTS IN MARINE WATERS AND SEDIMENTS

    Science.gov (United States)

    Ulva lactuca (sea lettuce) is a cosmopolitan marine attached green seaweed capable of sequestering high environmental levels of ammonia. Ammonia can be acutely toxic to marine organisms and is often found in dredged sediments from highly industrial areas or from areas with high c...

  14. Investigation on the effects of guava (Psidium guajava L. infusions on germination, root tips and meristematic cells of Latuca sativa

    Directory of Open Access Journals (Sweden)

    Jaquelini Luber

    2015-06-01

    Full Text Available Guava (Psidium guajava L. is a plant often employed in popular medicine. Recently several studies have alerted about the toxicity of substances present in medicinal plants, which can pose risks to the human health. In this sense, the present work aimed to investigate the phytotoxic, cytotoxic and genotoxic action of three guava varieties - Paluma, Pedro Sato and Roxa ("purple" - on the plant test system Lactuca sativa L. Thus, macro- and microscopic evaluations were carried out for five infusion concentrations (2.5, 5.0, 10.0, 20.0 and 40.0 g.L-1 prepared from each variety. Distilled water was used as negative control. Chromatographic and spectroscopic analysis by HPLC-PAD indicated that the chemical composition of the infusion of Roxa is different than that of the infusions of the varieties Paluma and Pedro Sato. It was observed that seed germination and root growth in L. sativa exposed to infusions decreased with increasing infusion concentration, regardless of the tested cultivar. For the mitotic index, no statistical differences were observed. On the other hand, a significant increase in the frequency of cell cycle alterations was verified, especially for the highest concentrations tested. The cytogenotoxic effect was significant. Therefore, guava should not be used indiscriminately in popular medicine.

  15. Investigation on the effects of guava (Psidium guajava L.) infusions on germination, root tips and meristematic cells of Latuca sativa.

    Science.gov (United States)

    Luber, Jaquelini; Palmieri, Marcel J; Botelho, Carolina M; Rinaldo, Daniel; Andrade-Vieira, Larissa F

    2015-01-01

    Guava (Psidium guajava L.) is a plant often employed in popular medicine. Recently several studies have alerted about the toxicity of substances present in medicinal plants, which can pose risks to the human health. In this sense, the present work aimed to investigate the phytotoxic, cytotoxic and genotoxic action of three guava varieties - Paluma, Pedro Sato and Roxa ("purple") - on the plant test system Lactuca sativa L. Thus, macro- and microscopic evaluations were carried out for five infusion concentrations (2.5, 5.0, 10.0, 20.0 and 40.0 g.L(-1)) prepared from each variety. Distilled water was used as negative control. Chromatographic and spectroscopic analysis by HPLC-PAD indicated that the chemical composition of the infusion of Roxa is different than that of the infusions of the varieties Paluma and Pedro Sato. It was observed that seed germination and root growth in L. sativa exposed to infusions decreased with increasing infusion concentration, regardless of the tested cultivar. For the mitotic index, no statistical differences were observed. On the other hand, a significant increase in the frequency of cell cycle alterations was verified, especially for the highest concentrations tested. The cytogenotoxic effect was significant. Therefore, guava should not be used indiscriminately in popular medicine.

  16. Qualidade de mudas de alface formadas em bandejas de isopor com diferentes números de células

    OpenAIRE

    Marques Patrícia Angélica A.; Baldotto Pedro Veridiano; Santos Ana Cláudia P.; Oliveira Leandro de

    2003-01-01

    Avaliaram-se os efeitos de três tipos de bandejas de isopor sobre a produção de mudas de alface cultivar Vera, e o posterior desempenho das plantas no campo. Para os experimentos de avaliação de mudas e de plantas adultas, os delineamentos foram o de blocos e inteiramente casualizado, respectivamente. Aos 26 dias após a semeadura foram avaliados o comprimento de raiz e o número de folhas das mudas. Após o transplante para os canteiros, mediram-se o comprimento da raiz e pesos da matéria fresc...

  17. Avaliação de substratos alternativos para a produção de mudas de alface

    OpenAIRE

    Costa, Kleyton Danilo da Silva; Universidade Federal de Alagoas; Carvalho, Islan Diego Espindula de; Universidade Federal de alagoas; Ferreira, Paulo Vanderlei; Universidade Federal de Alagoas; Silva, Jackson da; Universidade Federal de Alagoas; Teixeira, Jadson dos Santos; Universidade Federal de Alagoas

    2013-01-01

    O objetivo deste trabalho foi avaliar substratos alternativos para a produção de mudas de alface. Foi utilizado o delineamento inteiramente casualizado com 4 tratamentos constituídos pelos substratos: Bioplant®, Terra preta + húmus, Terra preta + húmus + fibra de coco, Terra preta + Torta de filtro + húmus, submetidos a 5 repetições, totalizando 20 parcelas constituídas por 14 mudas cada. As variáveis avaliadas foram: número de folhas (NF), número de folhas definitivas (NFD), comprimento de p...

  18. Viabilidade da consorciação de pimentão com repolho, rúcula, alface e rabanete

    OpenAIRE

    Rezende,Bráulio Luciano A; Cecílio Filho,Arthur B; Feltrim,Anderson Luiz; Costa,Caciana C; Barbosa,José Carlos

    2006-01-01

    O trabalho foi conduzido na UNESP, Jaboticabal-SP, de setembro/2003 a janeiro/2004, com objetivo de avaliar a viabilidade da consorciação de pimentão com as culturas de repolho, rúcula, alface e rabanete. O experimento constou de 15 tratamentos, correspondentes a 10 cultivos consorciados (combinações das cinco hortaliças) e cinco monocultivos. Utilizou-se o delineamento experimental em blocos casualizados, com seis repetições. Foram utilizados os híbridos Magali R e Kenzan, respectivamente, p...

  19. Biorefinery of the green seaweed Ulva lactuca to produce animal feed, chemicals and biofuels.

    Science.gov (United States)

    Bikker, Paul; van Krimpen, Marinus M; van Wikselaar, Piet; Houweling-Tan, Bwee; Scaccia, Nazareno; van Hal, Jaap W; Huijgen, Wouter J J; Cone, John W; López-Contreras, Ana M

    2016-01-01

    The growing world population demands an increase in animal protein production. Seaweed may be a valuable source of protein for animal feed. However, a biorefinery approach aimed at cascading valorisation of both protein and non-protein seaweed constituents is required to realise an economically feasible value chain. In this study, such a biorefinery approach is presented for the green seaweed Ulva lactuca containing 225 g protein ( N  × 4.6) kg -1 dry matter (DM). The sugars in the biomass were solubilised by hot water treatment followed by enzymatic hydrolysis and centrifugation resulting in a sugar-rich hydrolysate (38.8 g L -1 sugars) containing glucose, rhamnose and xylose, and a protein-enriched (343 g kg -1 in DM) extracted fraction. This extracted fraction was characterised for use in animal feed, as compared to U. lactuca biomass. Based on the content of essential amino acids and the in vitro N (85 %) and organic matter (90 %) digestibility, the extracted fraction seems a promising protein source in diets for monogastric animals with improved characteristics as compared to the intact U. lactuca . The gas production test indicated a moderate rumen fermentation of U. lactuca and the extracted fraction, about similar to that of alfalfa. Reduction of the high content of minerals and trace elements may be required to allow a high inclusion level of U. lactuca products in animal diets. The hydrolysate was used successfully for the production of acetone, butanol, ethanol and 1,2-propanediol by clostridial fermentation, and the rhamnose fermentation pattern was studied.

  20. Aspectos fisiológicos e bioquímicos da germinação de sementes de alface em diferentes temperaturas

    Directory of Open Access Journals (Sweden)

    Hugo Cesar Rodrigues Moreira Catão

    2014-04-01

    Full Text Available O objetivo deste trabalho foi avaliar os padrões eletroforéticos das proteínas resistentes ao calor e a atividade da enzima endo-β-mananase durante a germinação de sementes de alface, em alta temperatura. Sementes de oito cultivares de alface foram submetidas aos testes de germinação, primeira contagem e emergência em duas temperaturas, 20 e 35ºC. Foram calculados o índice de velocidade de germinação (IVG e o índice de velocidade de emergência (IVE. Avaliou-se, também, a expressão das proteínas resistentes ao calor e da enzima endo-β-mananase, para todos os tratamentos. Utilizou-se o delineamento experimental inteiramente casualizado, em arranjo fatorial 2x8, com duas temperaturas e oito cultivares. A maior germinação é observada a 35ºC na cultivar Everglades, considerada termotolerante. Os padrões de proteínas resistentes ao calor em sementes de alface apresentam bandas específicas na cultivar Everglades, a 35ºC. A atividade da enzima endo-β-mananase é maior na cultivar Everglades, nessa temperatura. Essa cultivar tem potencial para utilização em programas de melhoramento de alface com vistas à tolerância a altas temperaturas durante a germinação.

  1. Growing different Lactuca genotypes aeroponically within a tropical greenhouse – Cool rootzone temperatures decreased rootzone ethylene concentrations and increased shoot growth

    Directory of Open Access Journals (Sweden)

    Tsui Wei CHOONG

    2016-09-01

    Full Text Available Temperate crops cannot grow well in the tropics without rootzone cooling. As cooling increased production costs, this experiment aimed to study the growth of various Lactuca genotypes and propose possible ways of reducing these costs, without compromising productivity. A recombinant inbred line (RIL of lettuce and its parental lines (L. serriola and L. sativa ‘Salinas’ were grown aeroponically in a tropical greenhouse under 24 C cool (C or warm fluctuating 30-36 C ambient (A rootzone temperature (RZT. Their roots were misted with Netherlands standard nutrient solution for 1 min, at intervals of either 5 min (A5, C5 or 10 min (A10, C10 in attempting to reduce electricity consumption and production costs. Lower mortality and higher productivity were observed in all genotypes when grown in C-RZT. Higher shoot fresh weight was observed under C5 than C10, for the RIL and L. serriola. Since ‘Salinas’ had similar shoot fresh weight at both C-RZ treatments, this may indicate it is more sensitive to RZT than water availability. Under A-RZ treatments, higher carotenoid content, with correspondingly higher nonphotochemical quenching, was observed in A10 for the RIL and ‘Salinas’. Further, total chlorophyll content was also highest at this RZ treatment for the RIL though photochemical quenching was contrastingly the lowest. Cumulatively, productivity was compromised at A10 as the RIL seemed to prioritize photoprotection over efficiency in photosynthesis, under conditions of higher RZT and lower water availability. Generally, higher RZ ethylene concentrations accumulated in A10 and C10 than A5 and C5, respectively – probably due to spray frequency exerting a greater effect on RZ ethylene accumulation than RZT. In the C5 RZ treatment, lowest RZ ethylene concentration corresponded with highest shoot fresh weight. As such, further research on ethylene (insensitivity and water use efficiency could be conducted to identify Lactuca cultivars

  2. Resíduo da produção de Pochonia chlamydosporia no desenvolvimento de mudas e plantas de alface

    Directory of Open Access Journals (Sweden)

    José Ricardo Viggiano

    2012-07-01

    Full Text Available O objetivo deste trabalho foi avaliar o efeito de subproduto do processo de produção de Pochonia chlamydosporia var. chlamydosporia no desenvolvimento de mudas e plantas de alface. Esse subproduto, um resíduo constituído de arroz que continha propágulos do fungo, foi adicionado em diferentes concentrações (0, 2 e 4% volume de resíduo:volume de substrato a três tipos de substratos para mudas (formulado, comercial e fibra de coco. Sementes de alface foram semeadas em bandejas de isopor que continham os diferentes substratos enriquecidos com o resíduo. As mudas de alface foram transplantadas para vasos com o substrato solo e areia na proporção 1:1 (v:v, 28 dias após a semeadura. Todos os tipos de substratos e doses do resíduo apresentaram interação significativa para todas as variáveis relacionadas ao desenvolvimento das mudas e das plantas de alface. O maior desenvolvimento das mudas ocorreu na testemunha (sem o resíduo dos substratos. Entretanto, após o transplantio das mudas para os vasos, as doses de resíduo até 4 e 2% v:v - nos substratos formulado e comercial, respectivamente - foram as que promoveram o maior desenvolvimento das plantas. A utilização de até 2% v:v do resíduo nos substratos formulado e comercial é viável e não prejudica o desenvolvimento de plantas de alface.

  3. Avaliação de substratos alternativos para a produção de mudas de alface

    Directory of Open Access Journals (Sweden)

    Kleyton Danilo da Silva Costa

    2013-04-01

    Full Text Available O objetivo deste trabalho foi avaliar substratos alternativos para a produção de mudas de alface. Foi utilizado o delineamento inteiramente casualizado com 4 tratamentos constituídos pelos substratos: Bioplant®, Terra preta + húmus, Terra preta + húmus + fibra de coco, Terra preta + Torta de filtro + húmus, submetidos a 5 repetições, totalizando 20 parcelas constituídas por 14 mudas cada. As variáveis avaliadas foram: número de folhas (NF, número de folhas definitivas (NFD, comprimento de parte aérea (CPA, comprimento da raiz (CR, massa fresca da parte aérea (MFPA, massa fresca da raiz (MFRA, massa seca da parte aérea (MSPA e a massa seca da raiz (MSRA. O desempenho do substrato alternativo Terra preta + húmus + fibra de coco foi semelhante ao comercial em todas as variáveis, desta forma é indicado como uma alternativa para produção de mudas de alface.

  4. Alface à mesa: Implicações sócio-econômicas e ambientais da semente ao prato

    Directory of Open Access Journals (Sweden)

    Reges Echer

    2016-11-01

    Full Text Available Considerando as análises toxicológicas apresentadas pela ANVISA entre 2001 e 2011, e dados sócio-técnicos referentes às diferentes formas de cultivo da hortaliça, o presente trabalho busca elucidar e distinguir os caminhos que a alface trilha da horta à mesa do consumidor. Alicerçando-se numa ótica mais sustentável e seguindo o referencial bibliográfico disponível foi possível inferir sobre os limites e as possibilidades para a produção orgânica de alface, onde os sistemas de produção de base ecológica aparecem como uma alternativa viável e ascendente para a produção da hortaliça no Brasil, integrando conhecimentos populares e científicos com a conservação da biodiversidade local para o fornecimento de alimentos seguros e soberanos da semente ao prato, para o homem e para a natureza.

  5. Testes de vigor em sementes de alface Seed vigor tests for lettuce seeds

    Directory of Open Access Journals (Sweden)

    Ana Lúcia P Kikuti

    2012-03-01

    Full Text Available O vigor da semente tem sido avaliado por meio de testes fisiológicos, bioquímicos e de tolerância a estresse. Mais recentemente, com o uso da análise computadorizada de imagens de plântulas, podem ser obtidas informações objetivas, em período relativamente curto, com menor interferência humana. O objetivo nesta pesquisa foi identificar testes eficientes para avaliação do vigor de sementes de alface, com ênfase para a análise de imagens digitais de plântulas. Sementes de 12 lotes (seis da cultivar Vanda e seis da Vera foram avaliadas por meio de testes de germinação, germinação a baixa temperatura (15ºC, emergência de plântulas e envelhecimento acelerado tradicional e com solução salina (NaCl 40% saturada, a 41ºC/48 h e 41ºC/72 h. Utilizou-se, também, o sistema de análise computadorizada de imagens de plântulas (SVIS®, desenvolvido pela Ohio State University (EUA, que forneceu dados referentes ao índice de vigor, uniformidade e crescimento de plântulas. Os testes foram realizados a cada três meses, durante 12 meses de armazenamento, sob condições ambiente. Com base nos resultados obtidos, concluiu-se que os testes de envelhecimento acelerado com uso de solução saturada de NaCl, a 41ºC por 48 e 72 horas e de velocidade de germinação, e os parâmetros obtidos com o software SVIS, índice de crescimento de plântulas e comprimento da raiz primária, são eficientes na avaliação do vigor de lotes de sementes de alface.The seed vigor is evaluated by traditional tests and more recently by seedling imaging analysis to obtain objective information within a short period of time. The objective of the study was to verify the accuracy of accepted vigor tests in comparison to an automated computer imaging system for seedling evaluation (SVIS® in order to assess lettuce seed vigor. Six seed lots each of two cultivars (Vanda and Vera were evaluated in the germination, cold germination (15ºC, seedling emergence and

  6. Decontamination treatments to eliminate problem biota from macroalgal tank cultures of Osmundea pinnatifida, Palmaria palmata and Ulva lactuca

    OpenAIRE

    Kerrison, Philip D.; Le, Hau Nhu; Twigg, Gail C.; Smallman, Duncan R.; MacPhee, Rory; Houston, Fiona A. B.; Hughes, Adam D.

    2016-01-01

    The effect of a range of chemical disinfectants at different concentration and exposure times was investigated on five macroalgal species and the marine gastropod Littorina spp. Palmaria palmata, Osmundea pinnatifida and Ulva lactuca are commercially valuable and are often cultivated in tanks for food or feed. Ectocarpus siliculosus and Ulva intestinalis are common epiphytes of P. palmata and O. pinnatifida cultures, whilst Littorina spp. are common herbivorous epibionts within U. lactuca cul...

  7. Root constituents of Lactuca sibirica and a comparison of metabolite profiles of L. sibirica and L. tatarica

    Directory of Open Access Journals (Sweden)

    Wanda Kisiel

    2011-01-01

    Full Text Available Nine known sesquiterpene lactones, including four lactucin-type guaianolides, four costuslactone-type guaianolides and one germacranolide, were isolated from roots of Lactuca sibirica (Asteraceae, six of which were glycoside derivatives. The chemosystematic significance of the compounds is discussed in the context of sesquiterpenoids present in roots of the closely related species Lactuca tatarica. A comparison of sesquiterpene lactone profiles indicate that the species can be differentiated on the basis of their germacranolide glycoside compositions.

  8. Consórcio de rabanete, alface e quiabo e seu efeito sobre as características agronômicas das culturas, produção e índice de equivalência de área.

    OpenAIRE

    Sugasti, Juan Benjamin; Junqueira, Ana Maria Resende; Saboya, Pablo Aguiar

    2013-01-01

    O presente experimento foi realizado na Fazenda Água Limpa, Universidade de Brasília, no período de setembro de 2010 a janeiro de 2011. O delineamento experimental foi de blocos ao acaso com onze tratamentos e três repetições, sendo os tratamentos: alface (AL), rabanete (Rb), quiabo espaçamento aberto (Q1) e quiabo espaçamento tradicional (Q2), consórcio duplo: alface e rabanete (Al/Rb), alface e quiabo espaçamento aberto (AL/Q1), alface e quiabo espaçamento tradicional (AL/Q2), rabanete e qu...

  9. Estabilidade fenotípica de alfaces em diferentes épocas e ambientes de cultivo

    Directory of Open Access Journals (Sweden)

    João Pedro da Silva Queiroz

    Full Text Available Este trabalho teve como objetivo estimar a adaptabilidade e estabilidade fenotípica das cultivares de alface tipo crespa em diferentes épocas de cultivo em condições de alta temperatura. O delineamento experimental utilizado foi de blocos ao acaso em esquema fatorial 5 x 7 x 2, sendo cinco cultivares (Verônica, Vera, Cinderela, Isabela e Veneranda, sete ambientes (campo aberto, sombrite 30; 40; 50% de luz e malhas termo refletoras 30; 40 e 50% e duas épocas de cultivo (outubro a dezembro de 2008 e (julho a setembro de 2009, com quatro repetições. Em relação à produção total e produção comercial a cultivar Verônica foi a que se destacou com relação à produção. Houve diferença no desempenho produtivo das cultivares em relação às épocas de cultivo. E os parâmetros do coeficiente de determinação e índice de variação da variável número de folhas são próximos da unidade, apresentando uma maior estabilidade. A cultivar Verônica se manteve mais estável nos períodos de produção respondendo melhor às épocas de plantio independente dos ambientes de cultivos. A cultivar Cinderela, em relação às outras cultivares, manteve uma boa produção, sendo a segunda opção para o cultivo.

  10. Calagem em cultivos sucessivos de cenoura e alface Liming on crop rotation system of carrot and lettuce

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    Paulo E Trani

    2006-03-01

    Full Text Available A quantidade de calcário indicada de forma rotineira para hortaliças tem pouca experimentação de campo para dar suporte a níveis de aplicação. Neste trabalho procurou-se estabelecer valores para a saturação por bases (V e pH (CaCl2 para melhor produtividade e qualidade de cenoura (de inverno e alface (de verão, cultivadas sucessivamente por três anos agrícolas em um Argissolo Vermelho Amarelo em Monte Alegre do Sul (SP. Avaliou-se a calagem aplicada no ano, bem como o efeito residual da calagem no segundo e terceiro anos subseqüentes. Os tratamentos utilizados foram: 0; 2; 4; 6 e 8 t ha-1 de calcário no primeiro ano, e 4 e 8 t ha-1 de calcário no segundo e terceiro anos. Constatou-se efeito positivo da calagem sobre a produção e qualidade comercial da cenoura e da alface nos três anos agrícolas e efeito residual da calagem aplicada no primeiro ano do experimento sobre as produções de cenoura e alface nos anos seguintes. No primeiro ano, a produtividade de cenoura comercial foi de 24% a 39% maior do que a testemunha sem calcário, enquanto o peso médio da cabeça de alface aumentou de 79% a 199%. As maiores produtividades de cenoura foram de 46 t ha-1 obtidas com V=73% e pH (CaCl2= 5,7. As melhores produções de alface foram atingidas com V entre 72% e 80% e o pH (CaCl2 entre 5,5 e 5,6. A omissão de B, Cu, Mn e Zn em um dos tratamentos com calagem acarretou na queda de produtividade e qualidade da cenoura nos três anos agrícolas.Amounts of lime recommended for carrots and lettuce have little experimental support for the amounts indicated. This research was developed to determine the adequate value of soil bases saturation (V and pH (CaCl2 to obtain the best yield and commercial quality of carrot (winter and lettuce (summer cultivated on crop rotation system during three years. The experiment was carried out in Monte Alegre do Sul, São Paulo State, Brazil, on a Typic Kandaudult soil. The residual effect of liming, at the

  11. Use of seaweed Ulva lactuca for water bioremediation and as feed additive for white shrimp Litopenaeus vannamei

    Directory of Open Access Journals (Sweden)

    Regina Elizondo-González

    2018-03-01

    Full Text Available Two experimental feeding trials were conducted during four weeks to evaluate the use of Ulva lactuca in shrimp culture: (1 for wastewater bioremediation, and (2 using different inclusion levels of U. lactuca meal in shrimp feed. In feeding trial 1, shrimp reared under seaweed U. lactuca water exchange in a re-circulation system (SWE resulted in similar growth and feed utilization as shrimp reared with clean water exchange (CWE. Shrimp under no water exchange (NWE resulted in significant lower growth and higher feed conversion rate (FCR compared to the other treatments (p  0.05. In feeding trial 2, U. lactuca biomass produced by wastewater bioremediation in SWE treatment were dried and ground to formulate diets containing 0, 1, 2, and 3% U. lactuca meal (0UL, 1UL, 2UL, and 3UL. Shrimp fed the 3 UL diet resulted in a significant (p < 0.05 improvement of growth and FCR, and enhanced whole shrimp lipid and carotenoid content by 30 and 60%, respectively, compared to control diet. Seaweed U. lactuca is suggested as a desirable species for wastewater bioremediation in integrated aquaculture systems, and its meal as a good feed additive for farmed shrimp.

  12. Use of seaweed Ulva lactuca for water bioremediation and as feed additive for white shrimp Litopenaeus vannamei.

    Science.gov (United States)

    Elizondo-González, Regina; Quiroz-Guzmán, Eduardo; Escobedo-Fregoso, Cristina; Magallón-Servín, Paola; Peña-Rodríguez, Alberto

    2018-01-01

    Two experimental feeding trials were conducted during four weeks to evaluate the use of Ulva lactuca in shrimp culture: (1) for wastewater bioremediation, and (2) using different inclusion levels of U. lactuca meal in shrimp feed. In feeding trial 1, shrimp reared under seaweed U. lactuca water exchange in a re-circulation system (SWE) resulted in similar growth and feed utilization as shrimp reared with clean water exchange (CWE). Shrimp under no water exchange (NWE) resulted in significant lower growth and higher feed conversion rate (FCR) compared to the other treatments ( p   0.05). In feeding trial 2, U. lactuca biomass produced by wastewater bioremediation in SWE treatment were dried and ground to formulate diets containing 0, 1, 2, and 3% U. lactuca meal (0UL, 1UL, 2UL, and 3UL). Shrimp fed the 3 UL diet resulted in a significant ( p  Seaweed U. lactuca is suggested as a desirable species for wastewater bioremediation in integrated aquaculture systems, and its meal as a good feed additive for farmed shrimp.

  13. Neuropharmacological effects of Nigella sativa

    Science.gov (United States)

    Beheshti, Farimah; Khazaei, Majid; Hosseini, Mahmoud

    2016-01-01

    Nigella sativa (NS) (Ranunculaceae family) is generally utilized as a therapeutic plant all over the world. The seeds of the plant have a long history of use in different frameworks of medicines and food. In Islamic literature, it is considered as one of the greatest forms of therapeutics. It has been widely used to treat nervous system diseases such as memory impairment, epilepsy, neurotoxicity, pain, etc. Additionally, this is uncovered that the majority of therapeutic properties of this plant are due to the presence of thymoquinone (TQ) which is a major bioactive component of the essential oil. Pharmacological studies have been done to evaluate the effects of NS on the central nervous system (CNS). The present review is an effort to provide a detailed scientific literature survey about pharmacological activities of the plant on nervous system. Our literature review showed that NS and its components can be considered as promising agents in the treatment of nervous system disorders. PMID:27247928

  14. Clinical and Therapeutic Trials of Nigella Sativa

    Directory of Open Access Journals (Sweden)

    Ragaa H.M. Salama

    2010-10-01

    Full Text Available Seeds of Nigella sativa (N. sativa have been used for thousands of years as a spice and food preservative. The oil and seed constituents have shown potential medicinal properties in traditional medicine. This review lists and discusses different therapeutic trials of N. sativa seeds and its active ingredients in many diseases affecting body systems. It has anti–oxidant effects through enhancing the oxidant scavenger system that leads to antitoxic effects induced by several insults. Its anti–inflammatory effects conduct through suppression of the inflammatory mediators’ prostaglandins and leukotriens. Its immunomodulatory properties were proved by augmenting the T cell and natural killer cell–mediated immune responses. It expresses antimicrobial and anti–tumor properties toward different microbes and cancers. It decreases DNA damage and thereby prevents initiation of carcinogenesis in colonic tissue secondary to exposure to toxic agents. N. sativa is of immense therapeutic benefit in DM. It stimulates glucose–induced secretion of insulin besides having a negative impact on glucose absorption from the intestinal mucosa. N. sativa administration protects hepatic tissue from deleterious effects of toxic substances and attenuates hepatic lipid peroxidation. N. sativa provides a promising strategy that combines anti–inflammatory, antioxidants, and antineoplastics modes of action. [TAF Prev Med Bull 2010; 9(5.000: 513-522

  15. Review: Nigella sativa (Prophetic Medicine): A Review.

    Science.gov (United States)

    Ijaz, Hira; Tulain, Ume Ruqia; Qureshi, Junaid; Danish, Zeeshan; Musayab, Samina; Akhtar, Muhammad Furqan; Saleem, Ammara; Khan, Khanzada Khanzada; Zaman, Muhammad; Waheed, Imran; Khan, Imran; Abdel-Daim, Mohamed

    2017-01-01

    The present report is a significant effort to explore detail description of N. Sativa, its pharmacognostic characteristics, morphological characteristics, and mechanism of actions, doses and medicinal uses. Nigella sativa (N. Sativa) is greatest form of healing medicine. It is also known as Prophetic Medicine as its use has been mentioned in Prophetic Hadit, as natural remedy for all the diseases except death. It is recommended on daily basis in Tibb-e-Nabwi (Prophetic Medicine). Hazrat Abu Hurairah States ''I have heard from Rasool Allah (PBUH) that there is cure for every disease in black seeds except death and black seeds are shooneeze''. Salim Bin Abdullah narrates with reference to his father Hazrat Abdullah Bin Omar that Rasool Allah (PBUH) said, 'Let all the black seed upon you, these contain cure of all diseases except death'. N. sativa claimed to have anti-inflammatory, analgesic, hepato-protective, neuro-protective, gastro-protective and other useful properties. Biological and pharmacological effects are attributed to its two important constituents Thymoquinone (TQ) and Nigella sativa oil (NSO). TQ has interaction with human serum albumin. Seeds containing volatile oils mainly Melanthin showed toxicity at larger doses. This report is a reference for all pharmaceutical researchers, physicians and biologists researching on N. sativa and will open a door towards novel agent.

  16. Potential protective effects of polysaccharide extracted from Ulva lactuca against male reprotoxicity induced by thiacloprid.

    Science.gov (United States)

    Kammoun, Intissar; Bkhairia, Intidhar; Ben Abdallah, Fatma; Jaballi, Imen; Ktari, Naourez; Boudawara, Ons; Nasri, Moncef; Gharsallah, Neji; Hakim, Ahmed; Ben Amara, Ibtissem

    2017-12-01

    Polysaccharides (PSs) from seaweeds have been reported to possess biological activity of potential medicinal values. The current study was conducted to establish the protective effects of PS extracted from Ulva lactuca against oxidative stress induced by Thiacloprid (THC) in the rat reproductive system. Rats were exposed either to THC, THC + PS (100 mg/kg), or THC + PS (200 mg/kg). Our study showed that THC induced severe disorders in the functional sperm parameters. A decrease in antioxidant activities and their genes expression were observed in the same group, compared to the controls. Our molecular data showing also a severe DNA breakdown in the testis of THC treated group. Moreover, THC treated group showed severe histopathological changes. Our results revealed that PS extracted from Ulva lactuca alleviated the THC induced reprotoxicity and reduced oxidative stress damages, DNA breakdown and histological injuries in the testis.

  17. Production of acetone, butanol, and ethanol from biomass of the green seaweed Ulva lactuca.

    Science.gov (United States)

    van der Wal, Hetty; Sperber, Bram L H M; Houweling-Tan, Bwee; Bakker, Robert R C; Brandenburg, Willem; López-Contreras, Ana M

    2013-01-01

    Green seaweed Ulva lactuca harvested from the North Sea near Zeeland (The Netherlands) was characterized as feedstock for acetone, ethanol and ethanol fermentation. Solubilization of over 90% of sugars was achieved by hot-water treatment followed by hydrolysis using commercial cellulases. A hydrolysate was used for the production of acetone, butanol and ethanol (ABE) by Clostridium acetobutylicum and Clostridium beijerinckii. Hydrolysate-based media were fermentable without nutrient supplementation. C. beijerinckii utilized all sugars in the hydrolysate and produced ABE at high yields (0.35 g ABE/g sugar consumed), while C. acetobutylicum produced mostly organic acids (acetic and butyric acids). These results demonstrate the great potential of U. lactuca as feedstock for fermentation. Interestingly, in control cultures of C. beijerinckii on rhamnose and glucose, 1,2 propanediol was the main fermentation product (9.7 g/L). Copyright © 2012 Elsevier Ltd. All rights reserved.

  18. In vitro exposure of Ulva lactuca Linnaeus (Chlorophyta) to gasoline - Biochemical and morphological alterations.

    Science.gov (United States)

    Pilatti, Fernanda Kokowicz; Ramlov, Fernanda; Schmidt, Eder Carlos; Kreusch, Marianne; Pereira, Débora Tomazi; Costa, Christopher; de Oliveira, Eva Regina; Bauer, Cláudia M; Rocha, Miguel; Bouzon, Zenilda Laurita; Maraschin, Marcelo

    2016-08-01

    Refined fuels have considerable share of pollution of marine ecosystems. Gasoline is one of the most consumed fuel worldwide, but its effects on marine benthic primary producers are poorly investigated. In this study, Ulva lactuca was chosen as a biological model due to its cosmopolitan nature and tolerance to high levels and wide range of xenobiotics and our goal was to evaluate the effects of gasoline on ultrastructure and metabolism of that seaweed. The experimental design consisted of in vitro exposure of U. lactuca to four concentrations of gasoline (0.001%, 0.01%, 0.1%, and 1.0%, v/v) over 30 min, 1 h, 12 h, and 24 h, followed by cytochemical, SEM, and biochemical analysis. Increase in the number of cytoplasmic granules, loss of cell turgor, cytoplasmic shrinkage, and alterations in the mucilage were some of the ultrastructural alterations observed in thalli exposed to gasoline. Decrease in carotenoid and polyphenol contents, as well as increase of soluble sugars and starch contents were associated with the time of exposure to the xenobiotic. In combination, the results revealed important morphological and biochemical alterations in the phenotype of U. lactuca upon acute exposure to gasoline. This seaweed contain certain metabolites assigned as candidates to biomarkers of the environmental stress investigated and it is thought to be a promise species for usage in coastal ecosystems perturbation monitoring system. In addition, the findings suggest that U. lactuca is able to metabolize gasoline hydrocarbons and use them as energy source, acting as bioremediator of marine waters contaminated by petroleum derivatives. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Nitrogen fertilization on intercropping of lettuce and rocket Adubação nitrogenada em consórcio de alface e rúcula

    Directory of Open Access Journals (Sweden)

    Aurélio P Barros Júnior

    2011-09-01

    Full Text Available The work was carried out at UNESP, Jaboticabal, São Paulo State, Brazil, from September to December 2006, to evaluate the effect of nitrogen fertilization on intercropping of lettuce and rocket. The experiment was conducted in a randomized complete block design, with four replications, treatments being arranged in a 4 x 4 + 2 factorial design. The treatments were the result of a combination of four N rates for lettuce (0, 65, 130 and 195 kg ha-1 and four N rates for rocket (0, 65, 130 and 195 kg ha-1, plus two additional treatments, which corresponded to lettuce and rocket under single cropping. Veronica (lettuce and Folha Larga (rocket were the cultivars used. An increase in the N rate for both cultures, under intercropping system, caused fresh matter gains and higher yields for lettuce and rocket, maximizing the land equivalent ratio (1.84 at 127 kg ha-1 of N for lettuce and 195 kg ha-1 of N for rocket.O trabalho foi conduzido na UNESP, Jaboticabal-SP, de setembro a dezembro de 2006, com objetivo de avaliar o efeito da adubação nitrogenada em consórcio de alface e rúcula. O delineamento experimental foi de blocos casualizados completos, com quatro repetições, sendo os tratamentos arranjados em esquema fatorial 4 x 4 + 2. Os tratamentos resultaram da combinação de quatro doses de N para a alface (0, 65, 130 e 195 kg ha-1 e quatro doses de N para a rúcula (0, 65, 130 e 195 kg ha-1, mais dois tratamentos adicionais, correspondentes aos monocultivos de alface e rúcula. As cultivares utilizadas foram Verônica (alface e Folha Larga (rúcula. O aumento da dose de N para ambas as culturas, em consórcio, proporcionou incrementos na massa fresca e produtividade de alface e da rúcula e maximizou o índice de eficiência de uso da área (1,84 na dose 127 kg ha-1 de N para a alface e 195 kg ha-1 de N para rúcula.

  20. Toxicity of tire wear particle leachate to the marine macroalga, Ulva lactuca

    Energy Technology Data Exchange (ETDEWEB)

    Turner, Andrew, E-mail: aturner@plymouth.ac.u [School of Geography, Earth and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom); Rice, Lynsey [School of Geography, Earth and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom)

    2010-12-15

    Tire wear particles filed from the treads of end-of-life vehicle tires have been added to sea water to examine the release of Zn and the toxicity of the resulting leachate and dilutions thereof to the marine macroalga, Ulva lactuca. Zinc release appeared to be diffusion-controlled, with a conditional rate constant of 5.4 {mu}g[L(h){sup 1/2}]{sup -1}, and about 1.6% of total Zn was released after 120 h incubation. Exposure to increasing concentrations of leachate resulted in a non-linear reduction in the efficiency of photochemical energy conversion of U. lactuca and, with the exception of the undiluted leachate, increasing accumulation of Zn. Phototoxicity was significantly lower on exposure to equivalent concentrations of Zn added as Zn(NO{sub 3}){sub 2}, suggesting that organic components of leachate are largely responsible for the overall toxicity to the alga. Given the ubiquity and abundance of TWP in urban coastal sediments, the generation, biogeochemistry and toxicity of tire leachate in the marine setting merit further attention. - Tire wear leachate is toxic to Ulva lactuca and zinc is a potential bioindicator of leachate contamination in urban marine systems.

  1. Metabolic regulatory oscillations in intertidal green seaweed Ulva lactuca against tidal cycles.

    Science.gov (United States)

    Gupta, Vishal; Kushwaha, Hemant R

    2017-11-27

    The survival of wetland plant species largely relies on physiological adaptations essential for submergence and desiccation. Intertidal seaweeds, unlike terrestrial plants, have unique adaptations to submergence and can also sustain desiccation arising from tidal rhythms. This study determined the differential metabolic regulations in the inter-tidal seaweed species Ulva lactuca against the submergence and desiccation. During desiccation, the relative water content of the algal thalli declined with concomitant increase in reactive oxygen species (ROS) and lipid peroxidation. Nevertheless, the trends reversed during recovery on re-submergence and attained homeostasis. Metabolite profiling of U. lactuca revealed desiccation induced balance in energy reserve utilization by adjusting carbohydrate metabolism and switch over to ammonia metabolism. Upon re-submergence, thalli showed an increase in fermentative metabolites, pyruvate-alanine conversion, and the GABA shunt. Prolonged submergence induced substrate level phosphorylation mediated sugar biosynthesis while continuing the alternative carbon flux through fermentative metabolism, an increase in osmoprotectants glycine and betaine, sulfur bearing compounds cysteine and hypotaurine, and phenolic compound coniferaldehyde. The determined metabolic regulations in U. lactuca for submergence tolerance provide insights into potential evolutionarily conserved protective mechanisms across the green lineage and also highlights the possible role of sulfur oxoforms as strong free radical scavengers.

  2. Controle das plantas daninhas na cultura de alface transplantada com o herbicida oxadiazom Weed control in transplanted lettuce by oxadiazon

    Directory of Open Access Journals (Sweden)

    Edison Martins Paulo

    1990-01-01

    Full Text Available Efetuou-se um experimento com o herbicida oxadiazom, objetivando estudar o efeito do seu uso no controle das plantas daninhas e na, produção da cultura da alface transplantada. Os tratamentos, em número de sete, consistiram em três doses de oxadiazom formulado em grânulos, 1,0,1,5 e 2,0kg/ha, aplicadas após o transplante da alface, dois fratamentos de 1,0kg/ha do herbicida formulado em concentrado emulsionável, um pulverizado antes e, outro, após o transplante, em área total, e duas testemunhas, uma capinada e outra mantida com o mato até a colheita. As principais plantas daninhas que infestaram o experimento foram: beldroega (Portulacca oleracea L., picão-branco (Galinsoga parvifiora Cav., caruru (Amaranthus hibridus L., capim-colchão (Digitaria sanguinalis (L. Scop. e capim-pé-de-galinha (Eleusine indica (L. Gaertn.. Constatou-se o controle dessas espécies pelo oxadiazom, 51 dias após a aplicação, até que se mostrou seletivo à cultura, exceto na sua formulação concentrado emulsionável pulverizada após o transplante, quando reduziu o número e o peso das alfaces colhidas.A trial was carried out in order to study the performance of oxadiazon on yield of transplanted lettuce. The treatments were: oxadiazon granular formulation at rates of 1.0,1.5 and 2.0 kg/ha applied after transplanting and pre emergence of weeds; oxadiazom emulsifiable concentrate at 1.0 kg/ha applied before and after transplanting both as preemergence of weeds. Two controls were used: one without any control of weeds and another free from weeds 33 days after transplanting. Oxadiazon gave good control of Portulacca oleracea L, Galinsoga parviflora Cav., Amaranthus hibridus L, Digitaria sanguinalis (L. Scop, and Eleusine indica (L. Gaertn. up to 51 days after application. Except for oxadiazon emulsifiable formulation, when applied after transplanting, no phototoxicity to lettuce was observed with the herbicide whether applied at preemergence or before

  3. Cultivo da alface em túneis baixos de agrotêxtil Lettuce cultivation in low tunnels of agricultural textile

    Directory of Open Access Journals (Sweden)

    Aurélio P. Barros Júnior

    2004-12-01

    Full Text Available O experimento foi conduzido na horta da ESAM, de março a abril de 2004, com o objetivo de avaliar o desempenho de cultivares da alface em túneis baixos de agrotêxtil. O delineamento experimental utilizado foi de blocos casualizados completos em esquema fatorial 2 x 3, com quatro repetições. Os tratamentos foram constituídos pela combinação de duas cultivares de alface (Tainá e Babá de Verão e três tipos de cobertura (dois túneis baixos de 50 cm de altura de agrotêxtil branco com gramatura de 13 g/m² e 40 g/m² e sem cobertura. Avaliou-se a altura e diâmetro de plantas, número de folhas por planta, massa seca da parte aérea e produtividade. A cultivar Babá de Verão apresentou melhor desempenho em altura de plantas, número de folhas e produtividade. O túnel baixo de agrotêxtil branco com gramatura de 40 g/m² promoveu maior altura, diâmetro e produtividade de alface.The yield of lettuce cultivated under low tunnels of agricultural textile was evaluated in Mossoró, Rio Grande do Norte State, Brazil. The experiment was carried out from March to April of 2004, in a randomized complete blocks design with three treatments and four replications. The treatments were: low tunnel (with 50 cm of height of white agricultural textile with basic weight of 40 g/m²; low tunnel (with 50 cm of height of white agricultural textile with basic weight of 13 g/m² and control (treatment with no coverage. Evaluations of plant height and diameter, number of leaves per plant, shoot dry matter and yield were done. Cultivar Babá de Verão presented greater plant height, number of leaves per plant and yield. The low tunnel of agricultural textile with basic weight of 40 g/m² presented superior results of plant height, diameter and yield.

  4. Evaluation of Oryza sativa x O. glaberrima derived progenies for ...

    African Journals Online (AJOL)

    The genus Oryza has two cultivated species, Asian rice (Oryza sativa L.) and African rice (Oryza glaberrima Steud.) and 22 wild species. O. glaberrima is low yielding but has useful genes for resistance to biotic and abiotic stresses. Introgression lines derived from backcrossing of O. sativa x O. glaberrima, using O. sativa as ...

  5. Cardiovascular benefits of black cumin (Nigella sativa).

    Science.gov (United States)

    Shabana, Adel; El-Menyar, Ayman; Asim, Mohammad; Al-Azzeh, Hiba; Al Thani, Hassan

    2013-03-01

    Black Cumin (Nigella sativa), which belongs to the botanical family of Ranunculaceae, commonly grows in Eastern Europe, the Middle East, and Western Asia. Its ripe fruit contains tiny black seeds, known as "Al-Habba Al-Sauda" and "Al-Habba Al-Barakah" in Arabic and black seed or black cumin in English. Seeds of Nigella sativa are frequently used in folk medicine in the Middle East and some Asian countries for the promotion of good health and the treatment of many ailments. However, data for the cardiovascular benefits of black cumin are not well-established. We reviewed the literature from 1960 to March 2012 by using the following key words: "Nigella sativa," "black seeds," and "thymoquinone." Herein, we discussed the most relevant articles to find out the role of Nigella sativa in the cardiovascular diseases spectrum especially when there is a paucity of information and need of further studies in human to establish the utility of Nigella sativa in cardiovascular system protection.

  6. Produção e tolerância ao pendoamento de alface-romana em diferentes ambientes

    Directory of Open Access Journals (Sweden)

    Cárita Rodrigues de Aquino

    2014-08-01

    Full Text Available O experimento foi conduzido na área experimental da Universidade do Estado de Mato Grosso, localizada no município de Cáceres-MT, no período de maio a agosto de 2011, com o objetivo de avaliar a influência de diferentes ambientes e espaçamentos na produção e tolerância ao pendoamento de alface-romana cultivar Sophia. O delineamento experimental foi em blocos casualizados, arranjados em esquema fatorial 2 x 5, composto por dois espaçamentos (30 x 30 cm e 25 x 25 cm e cinco ambientes de cultivo (tela de sombreamento 30 e 50% , tela termorrefletora de 30 e 50% e ambiente aberto, perfazendo 10 tratamentos com quatro repetições cada. As parcelas experimentais foram constituídas por quatro linhas, com cinco plantas cada, totalizando 20 plantas por parcela. Consideraram-se como área útil para avaliação da produção as seis plantas centrais. As parcelas em que foi utilizado o espaçamento 30 x 30 cm apresentavam 1,8 m² cada, e as com o espaçamento 25 x 25 cm, 1,5 m² cada. As mudas foram transplantadas com 26 dias e a colheita realizada aos 46 dias após o transplantio. Observou-se que o espaçamento de 25 x 25 cm entre plantas e o ambiente aberto proporcionaram maior produtividade da alface-romana. Porém, o tempo para pendoamento das plantas no ambiente aberto foi menor que nos ambientes com as telas de sombreamento ou termorrefletora.

  7. Desempenho de cultivares de alface na região de Manaus Performance of lettuce cultivars in Manaus region

    Directory of Open Access Journals (Sweden)

    Isac N Rodrigues

    2008-12-01

    Full Text Available Na avaliação de cultivares de hortaliças, os rendimentos médios mais elevados nos ensaios de competição, associados a fatores de qualidade, são utilizados como critérios de recomendação para plantio. O presente trabalho teve como objetivo avaliar as cultivares de alface Frisella, Deisy, Tender Green, Lollo Bionda, Itapuã 401, Marisa, Verônica, Banchu New Red Fire e Hortência nas condições climáticas da região de Manaus, sob cultivo protegido e a campo. Foram avaliadas as características: massa fresca total, massa fresca comercial, diâmetro da cabeça e altura. As cultivares de alface Marisa, Itapuã 401 e Hortência são opções mais adequadas para o cultivo protegido e a campo na região, incluindo-se para o cultivo a campo a cultivar Verônica, a qual apresentou a melhor produção na avaliação realizada neste ambiente.In the evaluation of vegetable cultivars, the high average yield in the competition assays associated to quality factors are utilized as criteria to recommend cultivars. In the present work we evaluated the lettuce cultivars Frisella, Deisy, Tender Green, Lollo Bionda, Itapuã 401, Marisa, Verônica, Banchu New Red Fire and Hortência under the climatic conditions of the region of Manaus, under protected and conventional cultivation. The evaluated characteristics were: total and commercial weight, plant diameter and height. The lettuce cultivars Marisa, Itapuã 401 and Hortência presented higher production in both environments adding Verônica with best production under conventional cultivation.

  8. Conservação pós-colheita de alface cultivada com composto orgânico

    Directory of Open Access Journals (Sweden)

    Santos Ricardo Henrique Silva

    2001-01-01

    Full Text Available O objetivo deste trabalho foi avaliar o efeito da adubação com composto orgânico, na presença e na ausência de adubação mineral padrão, na conservação pós-colheita das plantas de alface cultivar Babá. O composto orgânico foi aplicado nas doses de 0,0, 22,8, 45,6, 68,4 e 91,2 t/ha de matéria seca. Foram avaliadas a perda de matéria fresca em condições de ambiente e a degradação da clorofila em câmara fria (4°C até 84 horas e 12 dias, respectivamente, após colheita. A aplicação de doses crescentes de composto orgânico reduziu a perda de matéria fresca após a colheita em até 7%; os teores de clorofila decresceram durante o armazenamento, em plantas adubadas com 45,6 e 91,2 t/ha de composto orgânico e adubo mineral, atingindo cerca de 0,3 mg/g de tecido fresco. A aplicação conjunta de adubo mineral e composto acelerou a senescência de alfaces mantidas em câmara fria, mas o cultivo com composto orgânico reduziu a perda de matéria fresca em condições de ambiente.

  9. Phytochemistry of Cannabis sativa L.

    Science.gov (United States)

    ElSohly, Mahmoud A; Radwan, Mohamed M; Gul, Waseem; Chandra, Suman; Galal, Ahmed

    Cannabis (Cannabis sativa, or hemp) and its constituents-in particular the cannabinoids-have been the focus of extensive chemical and biological research for almost half a century since the discovery of the chemical structure of its major active constituent, Δ 9 -tetrahydrocannabinol (Δ 9 -THC). The plant's behavioral and psychotropic effects are attributed to its content of this class of compounds, the cannabinoids, primarily Δ 9 -THC, which is produced mainly in the leaves and flower buds of the plant. Besides Δ 9 -THC, there are also non-psychoactive cannabinoids with several medicinal functions, such as cannabidiol (CBD), cannabichromene (CBC), and cannabigerol (CBG), along with other non-cannabinoid constituents belonging to diverse classes of natural products. Today, more than 560 constituents have been identified in cannabis. The recent discoveries of the medicinal properties of cannabis and the cannabinoids in addition to their potential applications in the treatment of a number of serious illnesses, such as glaucoma, depression, neuralgia, multiple sclerosis, Alzheimer's, and alleviation of symptoms of HIV/AIDS and cancer, have given momentum to the quest for further understanding the chemistry, biology, and medicinal properties of this plant.This contribution presents an overview of the botany, cultivation aspects, and the phytochemistry of cannabis and its chemical constituents. Particular emphasis is placed on the newly-identified/isolated compounds. In addition, techniques for isolation of cannabis constituents and analytical methods used for qualitative and quantitative analysis of cannabis and its products are also reviewed.

  10. Terpene synthases from Cannabis sativa.

    Directory of Open Access Journals (Sweden)

    Judith K Booth

    Full Text Available Cannabis (Cannabis sativa plants produce and accumulate a terpene-rich resin in glandular trichomes, which are abundant on the surface of the female inflorescence. Bouquets of different monoterpenes and sesquiterpenes are important components of cannabis resin as they define some of the unique organoleptic properties and may also influence medicinal qualities of different cannabis strains and varieties. Transcriptome analysis of trichomes of the cannabis hemp variety 'Finola' revealed sequences of all stages of terpene biosynthesis. Nine cannabis terpene synthases (CsTPS were identified in subfamilies TPS-a and TPS-b. Functional characterization identified mono- and sesqui-TPS, whose products collectively comprise most of the terpenes of 'Finola' resin, including major compounds such as β-myrcene, (E-β-ocimene, (--limonene, (+-α-pinene, β-caryophyllene, and α-humulene. Transcripts associated with terpene biosynthesis are highly expressed in trichomes compared to non-resin producing tissues. Knowledge of the CsTPS gene family may offer opportunities for selection and improvement of terpene profiles of interest in different cannabis strains and varieties.

  11. Desempenho agronômico de alface orgânica influenciado pelo sombreamento, época de plantio e preparo do solo no Acre

    Directory of Open Access Journals (Sweden)

    Eliana Mara Napoli Correia de Paula da Silva

    2015-06-01

    Full Text Available O objetivo deste trabalho foi avaliar o desempenho agronômico do cultivo de alface orgânica sob diferentes níveis de sombreamento, épocas de plantio e preparo do solo, no Acre. Para cada cultivar de alface avaliada, lisa (Baba de Verão e crespa (Vera, foram instalados quatro experimentos em ambientes com níveis distintos de sombreamento (casa de vegetação, 35%; tela, 50%; latada de maracujazeiro, 52%; e a pleno sol, em duas épocas de plantio (estiagem e chuvosa. Utilizou-se o delineamento de blocos ao acaso, com três métodos de preparo do solo (plantio direto, cultivo mínimo e preparo convencional e quatro repetições. O cultivo em casa de vegetação proporciona maior massa de matéria fresca e produtividade de alface 'Vera', e desempenho similar ao observado sob tela de sombreamento, com preparo mínimo do solo, para as duas épocas de plantio avaliadas. O cultivo a pleno sol, em plantio direto, proporciona maior massa de matéria fresca e produtividade de alface 'Vera', para o período de estiagem. A massa de matéria seca da parte aérea das cultivares Baba de Verão e Vera é maior em cultivo em casa de vegetação, seguida do cultivo sob tela de sombreamento.

  12. Podridão de raízes causada por Pythium aphanidermatum, em cultivares de alface produzidas em sistema hidropônico

    Directory of Open Access Journals (Sweden)

    Zayame Vegette Pinto

    2011-12-01

    Full Text Available A podridão de raízes, causada por Pythium aphanidermatum e outras espécies de Pythium, é a principal doença da alface cultivada em sistemas hidropônicos no Brasil. O presente trabalho teve como objetivo avaliar quatro cultivares comerciais de alface em relação à sensibilidade a podridão de raízes, causada por P. aphanidermatum. Os estudos foram realizados em placas de Petri contendo ágar-água com plântulas de alface das cultivares crespa (Vera e Verônica e lisa (Regina e Elisa, infestadas ou não com o patógeno. Com as mesmas cultivares foram realizados quatro experimentos em sistemas hidropônicos (Nutrient Film Technique, sendo dois em estufa coberta com plástico e sombrite e dois em estufa coberta apenas com plástico. As plântulas, infectadas ou não com P. aphanidermatum, foram transplantadas para os sistemas infestados ou não. Foi avaliada a severidade da doença e o desenvolvimento das plantas. Todas as cultivares foram suscetíveis à podridão de raízes nos experimentos realizados in vitro e in vivo. A presença do sombrite não reduziu a podridão de raízes em cultivares de alface produzidas no sistema hidropônico. A cultivar Regina apresentou maior massa de matéria seca da parte aérea e das raízes, na presença ou ausência do patógeno, sendo a mais indicada para o cultivo hidropônico na época mais quente do ano.

  13. Teor de nitrato em alface cultivada em sistemas hidropônico e convencional Level of nitrate in lettuce cultivated in hydroponic and conventional systems

    Directory of Open Access Journals (Sweden)

    Elisabete R. Yonamini Beninni

    2002-06-01

    Full Text Available O monitoramento do teor de nitrato nos alimentos é importante, uma vez que poderão ser formados compostos prejudiciais à saúde humana e animal após sua ingestão. Com o objetivo de avaliar o teor de nitrato presente em alface, foram coletadas e analisadas as folhas de alface crespa comercializada no Município de Londrina, cultivada em sistemas hidropônico e convencional. Os valores encontrados variaram entre 26 e 2.568 mg.kg-1 de peso fresco, sendo que as plantas cultivadas em sistema hidropônico apresentaram teores superiores em relação às cultivadas em sistema convencional, porém abaixo do limite máximo de nitrato permitido para alface, na Europa.The control of the nitrate level in foods is important because this substance may be harmful to human and animal health. The aim of this work was to evaluate nitrate levels in lettuce produced in hydroponic and conventional systems and commercialized in Londrina, Brazil. The nitrate concentration ranged from 26 to 2,568 mg.kg-1 fresh weight. Hydroponic lettuce showed higher levels of nitrate but in all cases the level of nitrate was lower than the maximum allowed by the Comission of the European Communities.

  14. Effect of Hydroalcoholic Extract of Lactuca Serriola on Blood Glucose in Streptozotocin (STZ- Induced Diabetic the Rats

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    F Mohamad janni

    2016-05-01

    Full Text Available Introduction: Diabetes mellitus (DM is a disorder caused by abnormal insulin secretion and is diagnosed by the presence of hyperglycemia. Insulin is one of the drugs used by diabetics patients .This drug also like other drugs has side effects, but in this way using herbal medicine is more effective. This study is to determine the effect of hydroalcoholic extract of Lactuca serriola on blood glucose in Streptozotocin (STZ- induced diabetic male rats. Methods: In study of 30 rats with an average weight of 200-230 g were divided into 5 groups consisted of 6 rats in each group comprised control, diabetic control and 3 groups treated orally with extract of Lactuca serriola. Diabetes was induced by STZ injection (IP at a dose of 50mg/kg. The doses of 250,350 and 450 mg/kg of extract were injected intraperitoneally during 6 weeks (40 days. The data were analyzed by one way variance analysis and Tukey’s test using SPSS Version 17 (p<0.05. Results: This research showed that the dosage of 250 mg/kg of extract of Lactuca serriola had less effect on blood sugar, and the dosage of 450 mg/kg of Lactuca serriola had a greater influence on blood sugar levels at different days, but dosage of 350 mg/kg  and dose of 450 mg/kg only could more significantly decrease the level of blood sugar. Conclusion: According the results of the study, the hydroalcolic extract of Lactuca serriola had the hypoglycemic effects on diabetic male rats  and it can be helpful for drug production in the control of Lactuca serriola. This drug consists of natural and synthetic substances: flavonoid, Alkaloid and Gamma-Aminobutyric Acid.

  15. Alface minimamente processada: uma revisão Minimally processed lettuce: a review

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    Liliane Corrêa MAISTRO

    2001-12-01

    Full Text Available Segurança e qualidade na produção de alimentos frescos são dependentes da microflora. Cada etapa da cadeia de produção desde o plantio até o consumo final influencia a qualidade microbiológica do alimento. Manipulação inadequada e ausência de procedimentos adequados, como a não sanitização dos equipamentos utilizados no beneficiamento, levam a um incremento do crescimento microbiano, podendo comprometer a qualidade e segurança de frutas e vegetais frescos. Por razões de ordem econômica e higiênica, o consumo de vegetais frescos pré-preparados, "prontos para consumo" (ready-to-eat, tornou-se bastante popular, pois se encontram disponíveis já higienizados e embalados nos mais diversos formatos, isto é, minimamente processados. Etapas de processamento como a picagem e o corte normalmente incrementam a população de microorganismos, diminuindo, conseqüentemente, a vida-de-prateleira do alimento. A utilização de técnicas para estender a vida-de-prateleira de um produto alimentício pode incrementar os riscos com problemas correlacionados com a segurança alimentar. O uso adequado de desinfetantes pode complementar um programa de sanitização, mas pode não obter sucesso absoluto na erradicação de microorganismos patogênicos em alimentos pré-contaminados. O objetivo desta revisão é apresentar os principais aspectos envolvendo a qualidade e segurança na produção da alface picada minimamente processada.Quality and safety of fresh produce depend on their microbial flora. Every step from production to consumption will influence the microbiology of fresh produce. Improper handling and unsanitary equipment lead to an increase in populations of microorganisms in fresh fruits and vegetables and can compromise quality and safety. For reasons of expense, labor and hygiene, fresh prepacked vegetables have become very popular, since they are already peeled, sliced, shredded, that is, minimally processed. Processing steps such

  16. The effect of soil environment on germination and emergence of prickly lettuce (Lactuca serriola L.

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    Jan Kapeluszny

    2012-12-01

    Full Text Available In 2007 mature achenes of prickly lettuce (Lactuca serriola L. were collected from a winter wheat crop growing on loess-derived brown earth soil, from the side of a dirt road, and from a hybrid alfalfa crop growing on heavy rendzina soil. In March 2008 the germination ability of achenes and the length of roots and above-ground parts of L. serriola seedlings were determined. The experiment was set up as a completely randomized design in 6 replicates and it was done in dishes. The dishes were filled with loess-derived brown soil and podzolic soil derived from light loamy sand with different pH values of 4.5, 5.5 and 7.0 obtained using laboratory methods. The second experiment evaluated the effect of medium type and light conditions on the germination of Lactuca serriola achenes. The experimental design was the same as in the above described experiment. The study found that there were significantly more germinating seeds from the plants growing in the alfalfa crop and on the dirt roadside compared to the plants from the wheat crop. Emerging plants showed higher germination ability on loess-derived soil with a pH of 5.5 and 7.0 than on podzolic soil derived from sand with the same pH. Lactuca serriola prefers soils rich in calcium compounds, and developing segetal cenopopulations produce diaspores capable of germination, thereby the numbers of individuals can increase and the continuity of this species in crop fields can be maintained. Seeds germinated significantly better in the dark than under the conditions of 12-hour illumination.

  17. Sterol composition of the Adriatic Sea algae Ulva lactuca, Codium dichotomum, Cystoseira adriatica and Fucus virsoides

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    RADOMIR KAPETANOVIC

    2005-12-01

    Full Text Available The sterol composition of two green algae and two brown algae from the South Adriatic was determined. In the green alga Ulva lactuca, the principal sterols were cholesterol and isofucosterol. In the brown alga Cystoseira adriatica, the main sterols were cholesterol and stigmast-5-en-3ß-ol, while the characteristic sterol of the brown algae, fucosterol, was found only in low concentration. The sterol fractions of the green alga Codium dichotomum and the brown alga Fucus virsoides contained practically only one sterol each, comprising more than 90 % of the total sterols (clerosterol in the former and fucosterol in the latter.

  18. Produtividade de cenoura e alface em sistema de consorciação Production of lettuce and carrot in an intercropping system

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    Luiz Carlos S. Caetano

    1999-07-01

    Full Text Available Com o objetivo de avaliar as culturas de cenoura e alface no sistema de consórcio, foram conduzidos dois experimentos na estação experimental da Pesagro-Rio em Campos dos Goytacazes, RJ, em cultivo de inverno nos anos de 1995 e 1996. As alfaces foram cultivadas em monocultivo e em consórcio com a cultura de cenoura. Utilizou-se delineamento experimental de blocos ao acaso com quatro repetições. Para cenoura foram analisados seis tratamentos (cenoura em monocultivo e em consórcio com cinco cultivares de alface. Para a alface foi utilizado esquema fatorial com dois sistemas de cultivo e cinco cultivares. As parcelas experimentais possuíam dimensões de 1 m x 1,5 m. No primeiro experimento, foram utilizadas as cultivares de alface Babá-de-verão, Regina-71, Vitória, Brasil-303 e Carolina e no segundo experimento, as cultivares Carolina, Elisa, Regina-71, Vitória e Marisa. A cultivar de cenoura utilizada foi a Brasília. A eficiência do consórcio foi avaliada pelo cálculo da Razão de Área Equivalente (RAE. Em ambos experimentos, tanto para monocultivo quanto para consórcio, as culturas apresentaram produção adequada para comercialização. Apenas houve prejuízo à cenoura no sistema de consórcio quando esta foi cultivada com a alface cv. Marisa. Os valores da RAE, 1,74 e 1,76, evidenciaram que a utilização do consórcio foi vantajosa nos dois ensaios, ou seja, para obter-se a mesma produção de alface ou cenoura em monocultivo seria necessário um acréscimo em área de 74% e 76%, considerando o primeiro e segundo ano de experimentação, respectivamente.Two experiments were conducted at the Campos Experiment Station - Pesagro-Rio, during the winter season of 1995 and 1996, to evaluate the performance of carrot and lettuce in an intercropping system. For the first experiment the lettuce cultivars comprised Babá-de Verão, Regina-71, Vitória, Brasil-303 and Carolina, whilst for the second experiment comprised Carolina, Elisa

  19. Polyketide synthases in Cannabis sativa L.

    NARCIS (Netherlands)

    Flores Sanchez, Isvett Josefina

    2008-01-01

    Cannabis sativa L. plants produce a diverse array of secondary metabolites, which have been grouped in cannabinoids, flavonoids, stilbenoids, terpenoids, alkaloids and lignans; the cannabinoids are the best known group of natural products from this plant. The pharmacological aspects of this

  20. Cannabis sativa allergy: looking through the fog.

    Science.gov (United States)

    Decuyper, I I; Van Gasse, A L; Cop, N; Sabato, V; Faber, M A; Mertens, C; Bridts, C H; Hagendorens, M M; De Clerck, L; Rihs, H P; Ebo, D G

    2017-02-01

    IgE-mediated Cannabis (C. sativa, marihuana) allergy seems to be on the rise. Both active and passive exposure to cannabis allergens may trigger a C. sativa sensitization and/or allergy. The clinical presentation of a C. sativa allergy varies from mild to life-threatening reactions and often seems to depend on the route of exposure. In addition, sensitization to cannabis allergens can result in various cross-allergies, mostly for plant foods. This clinical entity, designated as the 'cannabis-fruit/vegetable syndrome', might also imply cross-reactivity with tobacco, natural latex and plant-food-derived alcoholic beverages. Hitherto, these cross-allergies are predominantly reported in Europe and appear mainly to rely upon cross-reactivity between nonspecific lipid transfer proteins or thaumatin-like proteins present in C. sativa and their homologues, ubiquitously distributed throughout plant kingdom. At present, diagnosis of cannabis-related allergies predominantly rests upon a thorough history completed with skin testing using native extracts from crushed buds and leaves. However, quantification of specific IgE antibodies and basophil activation tests can also be helpful to establish correct diagnosis. In the absence of a cure, treatment comprises absolute avoidance measures. Whether avoidance of further use will halt the extension of related cross-allergies remains uncertain. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. Nigella sativa provides protection against metabolic syndrome ...

    African Journals Online (AJOL)

    Improvement in all other parameters like blood pressure, circumference of waist and serum triglyceride was also observed. Thus, Nigella seeds were found to be effective as an adjuvant therapy in patients of dyslipidemia and hyperglycemia. Keywords: Nigella sativa, toxicity, hyperglycemia, adjuvant, antihistaminic, ...

  2. Crescimento da alface sob saturação temporal do solo Growth of lettuce under temporary saturation of soil

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    Reginaldo G. Nobre

    2009-12-01

    Full Text Available Realizou-se este trabalho com o objetivo de estudar o crescimento de cultivares de alface 'Elba' e 'Irene', submetidas a saturação temporal do solo. O início do encharcamento ocorreu aos 17 dias após o transplante das mudas (DAT e constou de sete tempos de duração (0, 6, 12, 18, 24, 30 e 36 h de encharcamento, realizando-se as avaliações aos 22, 28 e 38 DAT, esta última por ocasião da colheita das plantas; fatorialmente combinados às duas cultivares, resultaram em 14 (7 x 2 tratamentos. O experimento foi instalado em blocos ao acaso, com três repetições, sendo a parcela constituída de um vaso com quatro plantas. O aumento da duração do encharcamento reduziu o crescimento e a produção de alface, sendo a fitomassa fresca da parte aérea a variável de maior sensibilidade ao estresse anoxítico. As cultivares são sensíveis à anoxia mas tenderam a recuperar parte do crescimento com o tempo pós-estresse. A cv. Elba foi superior à 'Irene' em termos de número de folhas, diâmetro e altura de caule, fitomassa seca da parte aérea e raiz; a 'Irene' se destacou em fitomassa fresca da parte aérea.This study was undertaken with the objective of studying the growth of the cultivars of lettuce ' Elba' and ' Irene', submitted to soil saturation of different duration. The beginning of waterlogging occurred 17 days after transplanting (DAT and it consisted of 7 duration times (0, 6, 12, 18, 24, 30 and 36 hours, evaluating the effects at 22, 28 and 38 DAT, this last one at the occasion of harvest of the plants; combined with two cultivars, resulted in 14 (7 x 2 treatments. The experiment was installed in randomized blocks, with three repetitions, the experiment consisted of one recipient with four plants. The increase in waterlogging duration reduced the growth and the lettuce production. The fresh dry matter of the aerial part being the variable of higher sensitivity to the anoxitic stress; the cultivars were sensitive to abiotic stress

  3. Genetic Transformation and Hairy Root Induction Enhance the Antioxidant Potential of Lactuca serriola L.

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    Mohamed A. El-Esawi

    2017-01-01

    Full Text Available Lactuca serriola L. is a herbaceous species, used for human nutrition and medicinal purposes. The high antioxidant capacity of L. serriola indicates the possibility of enhancing its edible and health potential by increasing the flavonoid and phenolic contents. The present study aimed at enhancing the production of phenolics and flavonoids by hairy root cultures in Lactuca serriola transformed with Agrobacterium rhizogenes strain AR15834 harbouring the rolB gene. The genetic transformation of rolB in transformed roots was validated, and rolB expression level was evaluated using real-time qPCR analysis. Expression levels of flavonoid biosynthesis genes (CHI, PAL, FLS, and CHS were assessed in the hairy and nontransformed roots. Results showed higher expression levels in the transgenic roots than in the nontransformed ones (p<0.01. Transgenic hairy roots exhibited a 54.8–96.7% increase in the total phenolic content, 38.1–76.2% increase in the total flavonoid content, and 56.7–96.7% increase in the total reducing power when compared with the nontransgenic roots (p<0.01. DPPH results also revealed that the transgenic hairy roots exhibited a 31.6–50% increase in antioxidant potential, when compared to normal roots. This study addressed the enhancement of secondary metabolite biosynthesis by hairy root induction in L. serriola.

  4. Role of Ulva lactuca Extract in Alleviation of Salinity Stress on Wheat Seedlings

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    Wael M. Ibrahim

    2014-01-01

    Full Text Available Seaweeds are potentially excellent sources of highly bioactive materials that could represent useful leads in the alleviation of salinity stress. The effects of presoaking wheat grains in water extract of Ulva lactuca on growth, some enzymatic activities, and protein pattern of salinized plants were investigated in this study. Algal presoaking of grains demonstrated a highly significant enhancement in the percentage of seed germination and growth parameters. The activity of superoxide dismutase (SOD and catalase (CAT increased with increasing the algal extract concentration while activity of ascorbate peroxidase (APX and glutathione reductase (GR was decreased with increasing concentration of algal extract more than 1% (w/v. The protein pattern of wheat seedling showed 12 newly formed bands as result of algal extract treatments compared with control. The bioactive components in U. lactuca extract such as ascorbic acid, betaine, glutathione, and proline could potentially participate in the alleviation of salinity stress. Therefore, algal presoaking is proved to be an effective technique to improve the growth of wheat seedlings under salt stress conditions.

  5. Lead (Pb heavy metal impacts in the green Ulva lactuca (Chlorophyceae marine algae

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    B. Saleh

    2016-05-01

    Full Text Available Toxicity of different lead (Pb (0, 2, 4 and 8 mg/L concentrations in the green Ulva lactuca (Chlorophyta marine algae at physiological level has been investigated 48 h after Pb treatment under laboratory conditions. Thalus algae damages followed Pb treatment as revealed by microscopy test showed that the 4 and 8 mg/L Pb caused morphological changes in cells viability; whereas, no effect observed at the lowest Pb applied concentration (2 mg/L. Data revealed that Pb stress caused reduction in most investigated physiological parameters i.e. Pigments content, osmotic potential and membrane stability index values. This decline in osmotic potential was significantly (p ≤ 0.001 different. Whereas, estimated electric conductivity (EC values increased significantly (p ≤ 0.001 as applied Pb concentration increased. The current study allowed somewhat to highlight and better understanding Pb impacts in U. lactuca algae. Thereby, the studied algae could be used as a useful bioindicator in Pb polluted ecosystems.

  6. Detection of Genetic Variations in Marine Algae Ulva lactuca (Chlorophyta Induced by Heavy Metal Pollutants

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    Basel Saleh

    2015-09-01

    Full Text Available Ulva lactuca (Chlorophyta green macroalgae has been successfully used as bioindicator for heavy metals pollution in ecosystems. Random amplified microsatellite polymorphism (RAMP marker was employed to investigate genetic DNA pattern variability in green U. lactuca 5 days after exposure to Cu, Pb, Cd and Zn heavy metals stress. Genomic template stability (GTS% value was employed as a qualitative DNA changes measurement based on RAMP technique. In this respect, estimated GTS% value was recorded to be 65.215, 64.630, 59.835 and 59.250% for Pb, Cu, Cd and Zn treatment, respectively. Moreover, genetic similarity (GS induced by the above heavy metals was also evaluated to measure genetic distance between algae treated plants and their respective control. In this respect, estimated GS values generated by RAMP marker ranged between 0.576 (between control and Zn treatment - 0.969 (for both case; between Pb and Cu and between Cd and Zn treatment with an average of 0.842. Based upon data presented herein based on variant bands number (VB, GTS% and GS values; the present study could be suggested that Pb and Cu followed similar tendency at genomic DNA changes. Similar finding was also observed with Cd and Zn ions. Thereby, RAMP marker successfully highlighted DNA change patterns induced by heavy metals stress.

  7. Distribution of genetic diversity in wild European populations of prickly lettuce (Lactuca serriola): implications for plant genetic resources management

    NARCIS (Netherlands)

    Wiel, van de C.C.M.; Sretenovic Rajicic, T.; Treuren, van R.; Dehmer, K.J.; Linden, van der C.G.; Hintum, van T.J.L.

    2010-01-01

    Genetic variation in Lactuca serriola, the closest wild relative of cultivated lettuce, was studied across Europe from the Czech Republic to the United Kingdom, using three molecular marker systems, simple sequence repeat (SSR, microsatellites), AFLP and nucleotide-binding site (NBS) profiling. The

  8. Evolution and genetic population structure of prickly lettuce (Lactuca serriola) and its RGC2 resistance gene cluster

    NARCIS (Netherlands)

    Kuang, H.; Eck, van H.J.; Sicard, D.; Michelmore, R.; Nevo, E.

    2008-01-01

    Genetic structure and diversity of natural populations of prickly lettuce (Lactuca serriola) were studied using AFLP markers and then compared with the diversity of the RGC2 disease resistance gene cluster. Screening of 696 accessions from 41 populations using 319 AFLP markers showed that eastern

  9. Acquisition and ecological characterization of Lactuca serriola L. germplasm collected in the Czech Republic, , Germany, the Netherlands and United Kingdom

    NARCIS (Netherlands)

    Lebeda, A.; Dolezalova, I.; Kristkova, E.; Dehmer, K.J.; Astley, D.; Wiel, van de C.C.M.; Treuren, van R.

    2007-01-01

    Expeditions were conducted in the Czech Republic, Germany, the Netherlands and United Kingdom in 2001 (partly 1998) to study Lactuca serriola L. (prickly lettuce, compass plant) geographic distribution, ecology, habitat characteristics and occurrence of diseases and pests on this species. During

  10. Nutrient uptake efficiency of Gracilaria chilensis and Ulva lactuca in an IMTA system with the red abalone Haliotis rufescens

    Directory of Open Access Journals (Sweden)

    Juan Macchiavello

    2014-07-01

    Full Text Available The current study examined the nutrient uptake efficiency of Ulva lactuca and Gracilaria chilensis cultivated in tanks associated with the wastewater of a land-based abalone culture. The experiments evaluated different seaweed stocking densities (1200, 1900, 2600, and 3200 g m-2 and water exchange rates (60, 80, 125, and 250 L h-1. The results show that both U. lactuca and G. chilensis were efficient in capturing and removing all of the inorganic nutrients originating from the abalone cultivation for all of the tested conditions. Furthermore, an annual experiment was performed with U. lactuca, cultivated at a stocking density of 1900 g m-2 and at a water exchanged rate of 125 L h-1, in order to evaluate seasonal changes in the nutrient uptake efficiency, productivity, and growth rate associated with the wastewater of a land-based abalone culture. The results confirmed high uptake efficiency during the entire year, equivalent to a 100% removal of the NH4, NO3, and PO4 produced by the land-based abalone culture. The growth rate and productivity of U. lactuca presented a marked seasonality, increasing from fall until summer and varying from 0.5 ± 0.2% to 2.6 ± 0.2% d-1 and 10 ± 6.1% to 73.6 ± 8.4% g m-2 d-1 for sustainable growth rate and productivity, respectively. We conclude that there is sufficient evidence that demonstrates the high possibility of changing the traditional monoculture system of abalone in Chile, to a sustainable integrated multi-trophic aquaculture system, generating positive environmental externalities, including the use of U. lactuca as a biofiltration unit.

  11. N transfer from green manures to lettuce in an intercropping cultivation system=Transferência de nitrogênio de adubos verdes para a alface cultivados em sistema de consórcio.

    Directory of Open Access Journals (Sweden)

    Eliana Aparecida Schammass

    2011-10-01

    Full Text Available The aim of this work was to evaluate the transfer of N via biological nitrogen fixation from green manures to intercropped lettuce using the 15N abundance method. The treatments consisted of lettuce with black oats, lettuce with cowpea, lettuce with white lupin and monocropped lettuce (control. Green manures were sown at two different times including the following: 60 days before transplanting of lettuce seedlings and simultaneous to transplanting of lettuce seedlings. N transfer was estimated using the natural 15N abundance method. It was observed that lettuce intercropped with green manures reached the same fresh mass of monocropped lettuce when the green manures were sown at the same time as the vegetables were planted. However, when the green manures were sown previously, the fresh mass of the monocropped lettuce was higher, and independent of the sowing time of green manures, the monocropped lettuce reached a higher dry mass. White lupin and cowpea transferred higher amounts of N regardless of sowing time, and the C:N ratio of white lupin to cowpea was lower compared to black oats. Intercropping with white lupin, cowpea and black oat transferred 18, 17 and 7% of N, respectively, to lettuce.O objetivo deste trabalho foi estudar a transferência do nitrogênio de adubos verdes para alface em cultivo consorciado, através da técnica da abundância natural de 15N. Os tratamentos foram: alface em monocultivo (testemunha, alface consorciado com aveia-preta, com feijão-caupi e com tremoço-branco, em duas épocas de semeadura dos adubos verdes: 60 dias antes e no transplante das mudas de alface. Observou-se que a alface consorciada com adubos verdes adquiriu a mesma massa fresca das alfaces solteiras quando a semeadura do adubo verde foi simultânea com o plantio da mesma; no entanto quando os adubos verdes foram semeados com 60 dias de antecedência as alfaces solteiras obtiveram maior massa fresca ; independentemente da época de semeadura as

  12. Development and application of a 6.5 million feature Affymetrix Genechip® for massively parallel discovery of single position polymorphisms in lettuce (Lactuca spp.

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    Stoffel Kevin

    2012-05-01

    Full Text Available Abstract Background High-resolution genetic maps are needed in many crops to help characterize the genetic diversity that determines agriculturally important traits. Hybridization to microarrays to detect single feature polymorphisms is a powerful technique for marker discovery and genotyping because of its highly parallel nature. However, microarrays designed for gene expression analysis rarely provide sufficient gene coverage for optimal detection of nucleotide polymorphisms, which limits utility in species with low rates of polymorphism such as lettuce (Lactuca sativa. Results We developed a 6.5 million feature Affymetrix GeneChip® for efficient polymorphism discovery and genotyping, as well as for analysis of gene expression in lettuce. Probes on the microarray were designed from 26,809 unigenes from cultivated lettuce and an additional 8,819 unigenes from four related species (L. serriola, L. saligna, L. virosa and L. perennis. Where possible, probes were tiled with a 2 bp stagger, alternating on each DNA strand; providing an average of 187 probes covering approximately 600 bp for each of over 35,000 unigenes; resulting in up to 13 fold redundancy in coverage per nucleotide. We developed protocols for hybridization of genomic DNA to the GeneChip® and refined custom algorithms that utilized coverage from multiple, high quality probes to detect single position polymorphisms in 2 bp sliding windows across each unigene. This allowed us to detect greater than 18,000 polymorphisms between the parental lines of our core mapping population, as well as numerous polymorphisms between cultivated lettuce and wild species in the lettuce genepool. Using marker data from our diversity panel comprised of 52 accessions from the five species listed above, we were able to separate accessions by species using both phylogenetic and principal component analyses. Additionally, we estimated the diversity between different types of cultivated lettuce and

  13. Avaliação dos efeitos alelopáticos de diferentes tipos de solo na germinação de alface

    Directory of Open Access Journals (Sweden)

    Josimar Rodrigues

    2010-01-01

    Full Text Available O objetivo deste trabalho foi avaliar a influência de três diferentes solos superficiais na germinação e desenvolvimento de alface. Foi utilizado delineamento experimental inteiramente casualizados (DIC, com três tratamentos e quatro repetições. Os tratamentos são: T1 - Solo superficial de eucalyptus urophylla, T2 - Solo superficial de eucalyptus camaldulensis e T3 – Solo superficial de Latossolo vermelho de pastagem. Realizou-se a semeadura direta nos recipientes, colocando-se três sementes de alface Regina (Horticeres Sementes, com 98% de taxa de germinação, tratadas com 0,15% de Captan. Os recipientes foram colocados em ambiente com luminosidade controlada, utilizando-se sombrete 50%. Após a germinação, as plântulas foram desbastadas deixando somente uma planta central por recipiente. Aos 24 dias após o plantio, foram mensurados o número de folhas, desconsiderando-se apenas os pares cotiledonares na contagem. Os tratamentos apresentaram diferenças estatisticamente significativas entre si, porém a alface apresentou melhor desenvolvimento nos tratamento com solo superficial de eucalyptus camaldulensis e eucalyptus urophilla, que não apresentaram efeito alelopático na cultura, porém no tratamento com solo superficial de um Latossolo Vermelho cultivado com pastagem, a cultura apresentou um desenvolvimento muito inferior quando comparado às médias dos demais tratamentos.

  14. Atividade biológica de extratos de espécies do Rio Grande do Norte em sementes de alface

    Directory of Open Access Journals (Sweden)

    Sandra Sely Silveira Maia

    2013-10-01

    Full Text Available 800x600 O objetivo no presente trabalho foi avaliar os efeitos alelopáticos de extratos aquosos de várias espécies na germinação e crescimento de plântulas de alface. Foram utilizados seis extratos: E1 – flores de Turnera subulata Smith, E2 - folhas de Turnera subulata Smith, E3 – folhas de Croton sonderianus Muell. Arg,  E4 – folhas de Ipomoea asarifolia (Ders. Roem. & Schult., E5 – flores de Ipomoea triloba L., E6 – flores de Centrosema brasilianum L. Benth. e E7 – testemunha. O delineamento experimental utilizado foi o inteiramente casualizado, com sete tratamentos e quatro repetições com 20 sementes. As características avaliadas foram a porcentagem de germinação, o índice de velocidade de germinação, o comprimento da parte aérea e o comprimento da raiz.  Os extratos E5, E1, E2 e E6, promoveram efeito negativo no IVG. O desenvolvimento das radículas de plântulas de alface foi mais afetado na presença dos extratos E5 e E6. O extrato E5 tem efeito alelopático negativo sobre a germinação e desenvolvimento de plântulas de alface e o extrato E3 tem efeito positivo no comprimento da raiz das plântulas. Os efeitos alopáticos dos extratos foram mais evidentes no índice de velocidade de germinação e desenvolvimento das plântulas. Normal 0 21 false false false PT-BR X-NONE X-NONE MicrosoftInternetExplorer4

  15. Mengenal Karakter Tanaman Alfalfa (Medicago Sativa L.)

    OpenAIRE

    Subantoro, Renan

    2009-01-01

    Alfalfa in Arab Ianguage have meaning as "Father from all food" trusted as functioning crop to heal various disease. Factor influencing growth of alfalfa crop is internal and eksternal factor. Inhibitor factor growth of alfalfa crop do not only land : land, water, temperature, and light intencity, and also weeds factor. Study in this article use literature study method from various source of research result and book which have been done by writer. The crop Alfalfa (Medicago Sativa L) hav...

  16. Produtividade de alface e qualidade de mudas de tomateiro com bioproduto de batata Lettuce productivity and quality of tomato seedlings with potato bioproduct

    Directory of Open Access Journals (Sweden)

    Diogo Vanderlei Schwertner

    2013-03-01

    Full Text Available O objetivo deste trabalho foi avaliar o efeito da aplicação de Acrescent Foliar®, proveniente da fermentação alcoolica de batata, na produtividade de alface e na qualidade de mudas de tomateiro. Foram conduzidos a campo dois experimentos com a cultura da alface, em delineamento blocos ao acaso com três repetições, e dois experimentos em ambiente protegido com mudas de tomateiro, em bandejas de poliestireno expandido de 128 células, em delineamento inteiramente casualizado com quatro repetições. Foram avaliados a fitomassa fresca e a fitomassa seca da parte aérea da alface, a altura da planta, o diâmetro do caule, o número de folhas, a fitomassa fresca de raiz, a fitomassa fresca de parte aérea, a fitomassa seca de parte aérea e a relação entre a fitomassa fresca de parte aérea e de raiz nas mudas de tomateiro. A adubação foliar com Acrescent Foliar® não influencia na produtividade da alface e confere às mudas de tomateiro características indesejáveis como redução da fitomassa fresca de raiz e aumento da relação entre a fitomassa fresca de parte aérea e de raiz.The aim of this work was to evaluate the effect of application of Acrescent Foliar® derived of alcoholic fermentation of potato, in lettuce productivity and in quality of tomato seedlings. Two experiments were conducted in field with lettuce crop in a randomized block design with three replications and, two experiments were conducted in greenhouse with production of tomato seedlings in polystyrene trays with 128 cells in a complete randomized design with four replications. It was measured the fresh and dry biomass of the shoot of lettuce, and the plant height, stem diameter, number of leaves, fresh biomass of roots and shoot, dry biomass of the shoot and, the relation between the fresh biomass of shoot and roots in tomato seedlings. The foliar fertilization with Acrescent Foliar® does not influence the lettuce productivity and it conferred undesirable

  17. Cronograma de amostragem de plantas de alface hidropônica para ajuste de curvas de crescimento Hydroponic lettuce sampling chronogram for fitting growth curves

    Directory of Open Access Journals (Sweden)

    Paula Machado dos Santos

    2007-12-01

    Full Text Available O ajuste de curvas de crescimento de plantas de alface durante seu ciclo necessita de amostragens no tempo, o que restringe o número de efeitos de tratamentos estudados. Com o objetivo de determinar o cronograma de amostragem de plantas de alface em hidroponia para o ajuste de curvas de crescimento até a fase de maturação das sementes, foram realizados dois cultivos em casa de vegetação durante a primavera e o outono, em área pertencente ao Departamento de Fitotecnia, na UFSM, Santa Maria, RS. A partir do ajuste de um modelo de crescimento com amostragem diária, simularam-se diferentes cronogramas de amostragem para o ajuste do mesmo modelo. Para encontrar o cronograma de maior intervalo entre amostragens, ou seja, menor número de coletas, foi comparado o ajuste do modelo de amostragem diária com os ajustes dos modelos dos diferentes intervalos de amostragens simulados, dois a dois, pelo teste F. Foram realizadas simulações considerando desde a data de transplante até a produção de sementes, para variáveis de fitomassa seca da planta e de partes da planta e área foliar. Em experimentos realizados com alface hidropônica na primavera, para o ciclo completo, recomendam-se amostragens a cada 3, 8, 20 e 9 dias para fitomassa seca relativa total da planta de alface, de folhas, de raiz e área foliar, respectivamente; enquanto que, para experimentos realizados no outono, é recomendável utilizar intervalos de amostragens a cada 2, 11, 12 e 11 dias, respectivamente.The fitting of growth curves for lettuce plants requires many samplings within o time interval, while can restrict the number of studied treatments. With the aim o determine sampling chronogram hidroponic lettuce for the fitting of growth curves until maturation of seeds. Two greenhouse trials were carried out in spring an autumn, at UFSM experimental area, Santa Maria, RS. Different sampling interval were simulated using the fitting of a daily model. The optimum sampling

  18. Produção de mudas de alface em função de diferentes combinações de substratos

    OpenAIRE

    Freitas,Gilson Araújo de; Silva,Rubens Ribeiro da; Barros,Hélio Bandeira; Vaz-de-Melo,Aurélio; Abrahão,Walter Antônio Pereira

    2013-01-01

    O substrato utilizado na produção de mudas exerce papel primordial, no desenvolvimento inicial da planta. Neste sentido, com o presente trabalho objetivou-se avaliar a produção de mudas de alface em função de diferentes combinações de substratos. O experimento foi implantado seguindo um delineamento inteiramente casualizado, com quatro repetições. Os 20 tratamentos foram dispostos em esquema fatorial 4x5; sendo o primeiro fator constituído por quatro substratos (PlantHort I, PlantHort II, Pla...

  19. Desempenho agroeconômico do bicultivo de alface em sistema solteiro e consorciado com cenoura Agrieconomic performance of lettuce under bicropping, sole crop and intercropped with carrot

    Directory of Open Access Journals (Sweden)

    Eliane Q. de Oliveira

    2004-12-01

    Full Text Available Dois experimentos foram implantados de setembro a dezembro/2002, na ESAM (RN, para avaliar o desempenho agroeconômico do bicultivo de dois grupos de alface em sistema solteiro e consorciado com duas cultivares de cenoura em faixas. O delineamento experimental foi de blocos balanceados em grupos, com quatro repetições. Foram avaliadas as cultivares pertencentes aos grupos crespa (Lucy Brown, Tainá, Laurel e Verônica e lisa (Babá de Verão, Maravilha das Quatro Estações, Elisa e Carolina. No experimento consorciado foi utilizado o esquema de parcelas sub-divididas, onde os tratamentos designados às parcelas foram as cvs. de cenoura Alvorada e Brasília e os designados às sub-parcelas foram as cvs. de alface do grupo crespa e as do grupo lisa. Na alface foi avaliado o rendimento de folhas e na cenoura o rendimento total, comercial e a classe das raízes. Foram usados índices agroeconômicos para medir a eficiência do sistema consorciado: Índice de Uso Eficiente da Terra, Renda Bruta, Renda Líquida, Vantagem Monetária, Vantagem Monetária Corrigida, Taxa de Retorno e Índice de Lucratividade. Não houve interação significativa entre os fatores cvs. de cenoura e cvs. de alface sobre os rendimentos das culturas. As cvs. de cenoura não influenciaram os rendimentos das culturas. As cvs. de alface não afetaram os rendimentos da cenoura. No bicultivo da alface consorciada com cenoura, recomenda-se o emprego das cvs Lucy Brown e Tainá do grupo crespa ou da 'Babá de Verão' e 'Maravilha das Quatro Estações' do grupo lisa no primeiro plantio. No segundo plantio, apenas a cv. do grupo lisa Maravilha das Quatro Estações se sobressaiu das demais no desempenho produtivo em cultivo consorciado.As cultivares de alface do grupo crespa consorciadas com cenoura se sobressaíram daquelas do grupo lisa no desempenho produtivo. Os consórcios cenoura 'Alvorada' x alface 'Lucy Brown'; e cenoura 'Brasília' x alface 'Maravilha das Quatro Esta

  20. Evaluación del lixiviado agroecológico como acondicionador del suelo en cultivo de lechuga (Lactuca sativa variedad crespa verde

    Directory of Open Access Journals (Sweden)

    Carlos Arturo Granada Torres

    2016-06-01

    Full Text Available La producción limpia en los últimos años ha alcanzado gran interés a nivel mundial, cada día los consumidores se preocupan más por la salud y han optado por el consumo de hortalizas que estén libres de agroquímicos y que no hayan sido regadas con aguas servidas. Los productores colombianos con el fin de lograr altos rendimientos y minimización de problemas fitosanitarios se han dedicado a realizar aplicaciones e incorporación de fertilizantes de síntesis química, alterando las dosis y utilizando aguas que no son aptas para riego, obteniendo como producto final cultivos con altas trazas de agroquímicos, metales pesados y microorganismos perjudiciales para la salud humana. Metodológicamente, se evaluó en campo el lixiviado agroecológico del cultivo de lechuga tomando en cuenta las variables: peso y tamaño de la cabeza de lechuga. Se encontró que el tratamiento con microorganismos eficientes presenta mayor peso y diámetro de cabeza de lechuga. Se concluye que el cultivo presenta mejores condiciones fitosanitarias y vigorosidad

  1. Distribusi Frekuensi Soil Transmitted Helminth pada Sayuran Selada (Lactuca sativa yang Dijual di Pasar Tradisional dan Pasar Modern di Kota Padang

    Directory of Open Access Journals (Sweden)

    Verdira Asihka

    2014-09-01

    Full Text Available AbstrakPenyakit kecacingan sampai saat ini masih merupakan masalah kesehatan di daerah tropis, termasuk Indonesia. Banyak faktor yang menyebabkan tingginya angka kejadian penyakit ini, salah satunya yaitu memakan sayuran mentah yang tidak dicuci bersih seperti selada atau kol yang sering dijadikan lalapan. Daun selada berposisi duduk sehingga dapat kontak langsung dengan tanah. Keadaan ini memungkinkan STH (Soil Transmitted Helminth yang berada ditanah akan mudah menempel pada daun selada. Tujuan peneliti melakukan penelitian ini adalah untuk mengetahui ada atau tidaknya STH pada selada yang dijual di pasar tradisional dan modern di Kota Padang. Penelitian ini dilakukan di Laboratorium Parasitologi Fakultas Kedokteran Universitas Andalas sejak Bulan September-Desember 2013. Penelitian ini berjenis deskriptif menggunakan metode sedimentasi. Hasil yang peneliti dapatkan dari penelitian ini adalah ditemukan STH positif pada 32 dari 44 sayuran selada dari pasar tradisional di Kota Padang dengan persentase 73%. Tiga dari 5 sayuran selada dari pasar modern di Kota Padang dinyatakan positif dengan persentase 40%. Jenis STH terbanyak yang peneliti temukan pada penelitian ini adalah telur Ascaris sp (79%, larva Trichostrongylus orientalis (16% dan telur cacing tambang (5%. Jadi, Terdapat kontaminasi STH pada selada yang dijual di pasar tradisional maupun pasar modern di Kota Padang.Kata kunci: Soil Transmitted Helminth, sayuran selada, pasar tradisional, pasar modernAbstractWorm disease is still a health problem in the tropics, including Indonesia. Many factors contribute to the high incidence of this disease, one of which is eating unwashed raw vegetables such as lettuce or cabbage cleaner is often used as vegetables. Lettuce sitting position so that it can direct contact with the ground. This situation allows STH ( Soil Transmitted Helminths that are ground will easily stick to the leaves selada. Purposes of researchers conducted this study was to determine the presence or absence of STH on lettuce sold in traditional markets and modern in the city of Padang. This research was conducted in the Laboratory of Parasitology, Faculty of Medicine, University of Andalas since Month from September to December 2013. This study was descriptive using sedimentation method. Researchers get results of this study were found positive on STH 32 of 44 lettuce from traditional markets in the city of Padang with a percentage of 73%. Three of 5 lettuce of the modern market in Padang tested positive with a percentage of 40%. Most types of STH that researchers have found in this study are the eggs of Ascaris sp (79%, Trichostrongylus orientalis larvae (16% and hookworm eggs (5%. So, There STH contamination on lettuce sold in traditional markets and modern markets in Padang.Keywords: Soil Transmitted helminths, lettuce, traditional markets, modern market

  2. Calidad y autenticidad de pimiento (Capsicum annum L.) y lechuga (Lactuca sativa L.) cultivados bajo sistemas de producción sostenibles

    OpenAIRE

    López Martínez, Alicia

    2014-01-01

    Los productos hortofrutícolas contienen, entre otros, compuestos bioactivos y antioxidantes tales como vitamina C, compuestos fenólicos, carotenoides, etc., que poseen propiedades beneficiosas para la salud. La concentración de estos compuestos en frutas y hortalizas, y por lo tanto la calidad funcional de las mismas, puede verse alterada por diversos factores pre-cosecha, entre ellos, factores genéticos y las prácticas agronómicas adoptadas. El primer objetivo de esta Tesis Doctoral fue estu...

  3. Shoot growth, root growth and resource capture under limiting water and N supply for two cultivars of lettuce (Lactuca sativa L.)

    NARCIS (Netherlands)

    Kerbiriou, P.J.; Stomph, T.J.; Putten, van der P.E.L.; Lammerts Van Bueren, E.; Struik, P.C.

    2013-01-01

    Background and aims - To improve vegetable crops adapted to low input and variable resource availability, better understanding is needed of root system functioning, including nitrogen and water capture. Methods - This study quantified shoot and root development and patterns of water and nitrate

  4. The effect of three liquid bio-fertilizers in the production of lettuce (Lactuca sativa L. and cabbage (Brassica oleracea L. var. capitata

    Directory of Open Access Journals (Sweden)

    Criollo Escobar Hernando Artemio

    2011-12-01

    Full Text Available

    In modern agriculture, the use of agrochemicals has grown considerably, increasing production costs and causing serious problems for the environment. The use of bio-fertilizers is a viable alternative to improve the profitability of crops, particularly for agriculture on medium and small-sized farms with intensive production systems, such as vegetables. Given that bio-fertilizers can be produced on the farm and used successfully in crop production, this research focused on the effect of three bio-fertilizers on the production of lettuce and cabbage, biweekly applications were made with liquid fertilizers produced from the manure of cows (BFC, guinea pigs (BFGp and pigs (BFPi and compared to a commercial foliar fertilizer (CFF and a control without an application. We observed the presence of Lactobacillus and Saccharomyces in the BFC and BFGp fertilizers and Bacillus in the BFPi fertilizer. The weight and head diameter and yield of lettuce and cabbage favored the bio-fertilizer applications compared to the control, but no statistical differences were found compared to the commercial foliar fertilizer (CFF. This behavior is attributed not only to the mineral content, but also to the presence of metabolite regulators of plant physiology, produced by the microbial action of the bio-fertilizers.

  5. Plasma membrane H(+)-ATPase is involved in methyl jasmonate-induced root hair formation in lettuce (Lactuca sativa L.) seedlings.

    Science.gov (United States)

    Zhu, Changhua; Yang, Na; Ma, Xiaoling; Li, Guijun; Qian, Meng; Ng, Denny; Xia, Kai; Gan, Lijun

    2015-06-01

    Our results show that methyl jasmonate induces plasma membrane H (+) -ATPase activity and subsequently influences the apoplastic pH of trichoblasts to maintain a cell wall pH environment appropriate for root hair development. Root hairs, which arise from root epidermal cells, are tubular structures that increase the efficiency of water absorption and nutrient uptake. Plant hormones are critical regulators of root hair development. In this study, we investigated the regulatory role of the plasma membrane (PM) H(+)-ATPase in methyl jasmonate (MeJA)-induced root hair formation. We found that MeJA had a pronounced effect on the promotion of root hair formation in lettuce seedlings, but that this effect was blocked by the PM H(+)-ATPase inhibitor vanadate. Furthermore, MeJA treatment increased PM H(+)-ATPase activity in parallel with H(+) efflux from the root tips of lettuce seedlings and rhizosphere acidification. Our results also showed that MeJA-induced root hair formation was accompanied by hydrogen peroxide accumulation. The apoplastic acidification acted in concert with reactive oxygen species to modulate root hair formation. Our results suggest that the effect of MeJA on root hair formation is media