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Os objetivos deste trabalho foram de determinar a sensibilidade ao etileno de sete cultivares de rosa para corte, determinar o período ideal de exposição, a melhor concentração de 1-MCP e, o efeito de aplicações múltiplas de 1-MCP sobre a qualidade pós-colheita das hastes florais de rosa. Para o experimento de sensibilidade ao etileno exógeno, utilizou-se um delineamento inteiramente casualizado com seis repetições em esquema fatorial 5x7, referente a cinco concentrações de etileno (0, 1, 10, 100 e 1000 L L-1) e sete cultivares de rosa. As cultivares Grand Gala, Versília, Texas, Konfetti, Tineke, Sandra e Vega, foram expostas ao etileno por um período de 12 horas. As hastes florais da cultivar Grand Gala apresentaram alta sensibilidade ao etileno, com reduzida vida pós-colheita, enquanto que hastes florais da cultivar Konfetti apresentaram maior resistência aos efeitos do etileno. Para o experimento com 1-MCP, utilizou-se um delineamento inteiramente casualizado com seis repetições em esquema fatorial 3x5, referente a três períodos de exposição (3, 6 e 12 horas) e cinco concentrações de Ethylbloc (0, 0,1, 0,5, 1,0 e 1,5 g/m3) nas cultivares Grand Gala e Konfetti. Para as hastes florais da cultivar Grand Gala, a concentração 1,5 g/m3 de Ethylbloc e período de exposição de 3 horas promoveram aumento da longevidade floral (7,2 dias). A máxima longevidade foliar estimada foi 5,1 dias para concentração de 1,5 g/m3 de Ethylbloc. O estádio máximo de abertura das flores foi 4,3 (diversas pétalas abertas), estimado com concentração de 1,5 g/m3 de Ethylbloc. Para as hastes florais da cultivar Konfetti, a concentração 1,5 g/m3 de Ethylbloc e período de exposição de 3 horas promoveram aumento na longevidade floral e foliar em 12,1 e 10,8 dias, respectivamente. Na concentração de 1,5 g/m3 e período de exposição 12 horas, o estádio de abertura das flores estimado foi 5,05 (botão floral completamente aberto). Para o experimento com aplicações múltiplas de 1-MCP utilizou-se um delineamento inteiramente casualizado com seis repetições em esquema fatorial 3x2, referente a três modos de aplicação do 1-MCP (simples, dupla e tripla aplicação) e duas concentrações de Ethylbloc (0 e 1,5 g/m3). As hastes florais das cultivares Grand Gala e Konfetti tratadas com aplicação simples de 1-MCP, apresentaram maior longevidade floral e foliar, quando comparados com aplicações dupla e tripla.

The objectives of this work were to evaluate the ethylene sensitivity of seven cut rose cultivars, to determine the ideal period of exposition, the best 1-MCP concentration, also the effect of multiple applications of 1-MCP on the quality of postharvest rose flowers. In the ethylene sensitivity experiment, the cultivars Grand Gala, Versília, Texas, Konfetti, Tineke, Sandra and Vega, were exposed to five ethylene concentrations (0, 1, 10, 100 and 1000 L L-1), in factorial 5x7 completely randomized design with six replicates. The Grand Gala cultivar exhibited high ethylene sensitivity, with reduced life postharvest, while the Konfetti cultivar presented higher…

Advisors/Committee Members: José Ivo Ribeiro Junior, José Geraldo Barbosa, Gilberto Bernardo de Freitas, Ernesto José Resende Rodrigues, José Antônio Saraiva Grossi, Fernando Luiz Finger.

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Mestrado em Engenharia Agronómica - Instituto Superior de Agronomia

Efficacy of the ethylene action inhibitor 1-methylcyclopropene (1-MCP) was evaluated in pear (Pyrus communis L.) ‘Rocha’ in comparison with the standard postharvest treatments currently used by the Portuguese pear industry. Fruit were harvested at commercial maturity from four representative orchards in the Oeste Region, Portugal, subjected to the postharvest treatments and stored at 0 ºC, 90-95% relative humidity, under normal atmosphere, for up to 6 months; under controlled atmosphere, for up 9 months, and 9 months under delayed controlled atmosphere with the first 2 months in normal air. 1-MCP, at the recommended dosis of 312 nL L-1, reduced fruit softening and skin yellowing, and increased the soluble solids content (SSC) of ‘Rocha’ pear during shelf-life (14 days) at room temperature following cold storage in comparison with control fruit. SmartFresh at the recommended dosis of 312 nL L-1 of 1-MCP was also more effective than the standard postharvest treatments in reducing the incidence of superficial scald and internal browning disorders in ‘Rocha’ pear. It is concluded that 1-MCP at 312 nL L-1 is effective in reducing physiological disorders in ‘Rocha’ pear under refrigerated storage and controlled atmosphere and in delaying ripening-related softening and color changes during shelf-life.

Advisors/Committee Members: Oliveira, Cristina Maria Moniz Simões.

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A maçã cultivar Eva, produzida em Minas Gerais, apresenta características interessantes para o setor agrícola por apresentar baixa exigência em frio, ser uma cultivar precoce com alta produtividade e boa qualidade dos frutos. Por este motivo, o presente trabalho foi realizado com o objetivo de realizar a caracterização do fruto, com ênfase nos seus atributos físicos, físico-químicos, químicos e bioquímicos, bem como a extensão de sua vida útil e a manutenção de sua qualidade, por meio da otimização de técnicas de conservação, tais como 1-metilciclopropeno, irradiação gama e modificação atmosférica. As amostras, coletadas manualmente na cidade de Barbacena, MG, foram selecionadas quanto à ausência de injúrias e divididas em grupos. No primeiro grupo, os frutos foram submetidos a diferentes doses de 1-metilciclopropeno (0, 10, 50, 100 e 500 mg.L-1). Maçãs do segundo grupo foram armazenadas em diferentes embalagens (polipropileno, polietileno de alta densidade e polietileno de baixa densidade), as quais continham cinco frutos cada. O terceiro grupo de frutos foi submetido a diferentes doses de irradiação (0, 0,5; 1,0 e 1,5 kGy). Após a aplicação dos tratamentos, todos os frutos foram armazenados em câmara fria, a 0,50,5C, por até 225 dias. Por meio dos parâmetros analisados neste trabalho pode-se sugerir o consumo ao natural da maçã Eva produzida em Minas Gerais por possuir alta qualidade e características interessantes capazes de agradar aos consumidores brasileiros. O 1-MCP foi capaz de retardar o incremento da produção de etileno durante o armazenamento de maçãs da Eva e assim diminuir o seu metabolismo. O controle dos gases por meio de atmosfera modificada no armazenamento pós-colheita de maçãs Eva permitiu a conservação dos frutos com qualidade por até sete meses tendo o filme de polietileno de alta densidade mostrado, para a maioria das variáveis analisadas, os melhores resultados. A irradiação gama foi capaz de preservar os compostos fenólicos, manter os teores de vitamina C e manter a qualidade dos frutos percebida pelos menores teores de sólidos solúveis, sendo que, quanto menor a dose utilizada, melhor a resposta dos frutos.

The apple cultivar Eva, produced in Minas Gerais, presents interesting features for the agricultural sector due to its low demand in cold be a early variety with hight yields and good fruit quality. For this reason, the objective of this work was the characterization of the fruit, with emphasis on their physical attributes, physical-chemical, chemical and biochemical, as well as the extension of its life and maintain their quality through optimization techniques conservation, such as 1-methylcyclopropene, gamma irradiation and modified atmosphere. The samples, collected manually in the city of Barbacena, Minas Gerais state, were selected for the absence of injury and divided into groups. In the first group, the fruits were subjected to different doses of 1-methylcyclopropene (0, 10, 50, 100 and 500 mg.L-1). Apples in the second group were stored in different packaging (polypropylene,…

Advisors/Committee Members: Patrícia de Fátima Pereira Goulart, Andrea Luiza Ramos Pereira Xisto, Celeste Maria Patto de Abreu, Émerson Dias Gonçalves, Luiz Carlos de Oliveira Lima.

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Objetivando compreender o processo de amadurecimento do caqui Fuyu e prolongar o armazenamento foram conduzidos experimentos para avaliar o efeito do período de exposição à baixa temperatura, atmosfera controlada e aplicação de inibidor da ação do etileno em dois momentos, no início e no final do armazenamento, sobre o amolecimento, analisados visualmente. No primeiro experimento avaliou-se: [1] 3 dias na temperatura de -0,5C; [2] 6 dias na temperatura de -0,5C; [3] 9 dias na temperatura de -0,5C; [4] 6 dias na temperatura de 10C; [5] 9 dias na temperatura de 10C; [6] 15 dias na temperatura de 10C; [7] 9 dias na temperatura de 15C e [8] 15 dias na temperatura de 15C. No segundo experimento, os tratamentos foram originados da combinação de temperaturas (-0,5; 10; 12,5; 15 e 17,5C) com e sem aplicação de 1-metilciclopropeno (1-MCP), antes do armazenamento. As análises laboratoriais foram realizadas após 1 e 2 meses de armazenamento. No terceiro experimento, na temperatura de -0,5C foram avaliados os seguintes tratamentos: [1] AR; [2] aplicação de 1ppm de 1-MCP durante 24h e posterior AR; [3] AR e posterior aplicação de 1ppm de 1-MCP durante 24h; [4] atmosfera controlada (AC) com 1,0kPa de O2 + 8,0kPa de CO2; [5] aplicação de 1ppm de 1-MCP 24h e posterior armazenamento em AC; [6] armazenamento em AC e posterior aplicação de 1ppm de 1-MCP. As análises laboratoriais foram realizadas após 2 meses nos frutos armazenados em AR e após 4 meses nos frutos armazenamentos em AC. Segundo os resultados dos experimentos, o período de 9 dias na temperatura de -0,5C não fornece frio suficiente para estimular o processo de maturação do caqui, não alterando a produção de etileno, a respiração e o amolecimento dos frutos em relação a 15C. O armazenamento de caqui por um mês na temperatura de -0,5C é suficiente para estimular o processo de maturação, com 100% dos frutos amolecidos aos 6 dias de exposição a 20C. Já, o armazenamento por dois meses na temperatura de -0,5C torna 100% dos frutos amolecidos aos 4 dias de exposição a 20C. As temperaturas de 10; 12,5 e 15C ocasionam amolecimento dos frutos durante o armazenamento, o que indica que essas temperaturas por longo período de tempo também são eficientes no desbloqueio da maturação. O amolecimento tem relação com a ação do etileno e, mais provavelmente, com o seu receptor. A aplicação de 1-MCP, antes ou após o armazenamento, bloqueia o processo de maturação, mesmo em frutos expostos ao frio de -0,5C, evitando o amolecimento do caqui após exposição a 20C. A atmosfera controlada retardou o amolecimento, sendo que a condição de AC de 1,0kPa de O2 + 8,0Pa de CO2 com aplicação de 1-MCP foi a condição mais eficiente no controle da maturação, mas ocorreu alta incidência de podridão após 4 meses de armazenamento.

Aiming to understand the mechanism of ripening of the Fuyu persimmon and extend the storage period, experiments were preformed to evaluate the effect of the period of exposure to low temperature, controlled atmosphere and inhibitor the ethylene action in the beginning or in the end…

Advisors/Committee Members: Cristiano André Steffens, Auri Brackmann, Adriano Arriel Saquet.

▼ Cotton (Gossypium hirsutum L.) crops usually experience some type of environmental stress during the season. Soil moisture deficits along with high temperatures pose the biggest constraints for crop productivity. Although usually hard to distinguish between drought and high temperature stress effects, it is important to develop means to help mitigate the negative impacts of such stresses on crop productivity. The 1-methylcyclopropene (1-MCP) is an ethylene antagonist that acts by binding to ethylene receptors, thus delaying and/or diminishing its effects on plants. Recently 1-MCP became the focus of several studies due to its potential to mitigate negative impacts of abiotic stresses. The main objective of this research was to assess the impact of 1-MCP on field grown cotton. The secondary objective was to investigate the association of canopy temperature (CT), canopy temperature depression (CTD), stress degree day (SDD), thermal stress index (TSI), and crop water stress index (CWSI) with crop yield. Field studies were conducted at the Texas A&M University Field Laboratory in Burleson County, TX from 2012 to 2014. Plots were arranged in a randomized complete block design and replicated four times. Treatments consisted of 1-MCP application (25 g a.i. ha^-1) triggered by canopy temperature (28 °C) and forecasted ambient temperatures (35 and 27.8 °C). For the secondary objective treatments were two irrigation levels, namely, dryland and irrigated. Results indicated that 1-MCP had little to no effect on the physiology and morphology of cotton at different stages of crop development. Daily plant canopy temperature, net photosynthesis, transpiration, and photosystem II quantum yield were affected by 1-MCP treatment when plants were irrigated, but not under dryland conditions. Effects of 1-MCP applications during different seasons were inconsistent. Ultimately, 1-MCP treatment effects were not enough to increase final seedcotton yield under the conditions tested. Negative relationships between yield and CT (r² = 0.66), yield and TSI (r² = 0.70), and yield and CWSI (r² = 0.58) were found. CTD and SDD showed great distinction between the humid (2012 and 2014) and dry (2013) years, and to a lesser extent, this was also apparent for CWSI. Evidence suggests that CTD, SDD, and CWSI models should be interpreted with caution, particularly in locations where great inter-annual weather variability occurs. Advisors/Committee Members: Heilman, James L (advisor), Fernandez, Carlos J (advisor), da Costa, Vladimir (committee member), Rajan, Nithya (committee member), Morgan, Gaylon (committee member).

▼ Studies were conducted with a sprayable formulation of 1-methylcyclopropene (1-MCP), formulation AFxRD-038 (Rohm and Hass, Philadelphia, PA), to determine the sensitivity to exogenous ethylene and efficacy of 1-methylcyclopropene (1-MCP) on bedding plants. Effects of ethylene concentration, plastic bag enclosure, 1-MCP concentration and volume, water quality, solution age, timing and length of irrigation, delay of ethylene challenge, surfactants, extended darkness and high postproduction storage temperatures on efficacy of 1-MCP in protecting Impatiens walleriana and I. hawkeri from premature floral senescence were evaluated. The sensitivity to exogenous ethylene and efficacy of sprayable formulation of 1-MCP of seventy-three cultivars from twenty species of annual bedding plants was investigated. Impatiens walleriana and I. hawkeri exposure to 1.0 [MICRO SIGN]l⋅liter-1 ethylene for 18 hours caused complete senescence of open flowers, 1-MCP at 2.5 mg ai⋅liter-1 protected plants from ethylene exposure. Placing plants in unsealed High Density Polyethylene (HDPE) produce bags had no effect on flower abscission in the presence or absence of ethylene or 1-MCP. At 5 and 10 mg ai⋅liter-2, the efficacy of 1-MCP increased as spray volume increased from 102 ml⋅meter-2 to 306 ml⋅meter-2. 1-MCP appeared to be effective within 1 minute after application with no decrease in efficacy regardless of irrigation water applied after 1-MCP pretreatment. There was no significant effect of surfactant concentration (Capsil, Aquatrols, Paulsboro, NJ) on 1-MCP activity though some plants exhibited phytotoxicity symptoms on flower petals with Capsil rates above 1.0 ml⋅liter-1. Increasing pH of the 1-MCP solution from 6 to 9 resulted in slightly reduced efficacy but not enough to reduce marketability of plants. Prepared 1-MCP solutions (10 mg ai⋅liter-1) remained effective up to two weeks after mixing if held in airtight containers. With Impatiens, 1-MCP provided protection against exogenous ethylene for a maximum of four days. 1-MCP provided protection against darkness and high temperature stress related abscission for at least three days of extended darkness in the absence of ethylene and two days at high temperatures (28 °C). In the second study, 73 cultivars from twenty species of annual bedding plants were grown from seed or vegetative cuttings under optimum greenhouse production until mature at which time they were sprayed with 0 or 25 mg ai⋅liter-1 1-MCP and then exposed to 0 or 1.0 [MICRO SIGN]l⋅liter-1 for 18 hours in darkness at 21°C to simulate postproduction stress. Immediately after postproduction stress, plants were assessed for senescence symptoms including flower abscission, wilting or discoloration, leaf epinasty and abscission. There were three groups of ethylene sensitivity: no response to ethylene (Bidens ferulifolia, Heliotropium arborescens, Osteospermum ecklonis, Scaevola aemula), transient ethylene symptoms (Solenostemon scutellarioides), and permanent ethylene damage. Plants showing ethylene damage were split into two… Advisors/Committee Members: Miller, William (chair), Gomez, Miguel I. (committee member).

▼ Um dos principais problemas de qualidade da uva de mesa está relacionado com a facilidade de degrane, ou queda das bagas, depois da colheita dos cachos, devido ao desenvolvimento da zona de abscisão. Este estudo teve como objetivo avaliar o efeito da aplicação de cloreto de cálcio (CaCl2) e 1-MCP (1-metilciclopropeno) na conservação pós-colheita em diferentes condições de armazenamento de uva Isabel‟ produzidas na região do Vale do Sirijí (PE/PB), conduzido em três experimentos. O primeiro experimento avaliou uvas Isabel‟ produzidas no município de Natuba-PB, aplicando cloreto de cálcio (CaCl2) na pós-colheita associado à atmosfera modificada (AM) visando avaliar a manutenção da qualidade no armazenamento refrigerado à 121C e 852% de UR. O delineamento inteiramente casualizado, em esquema fatorial 5 x 2 x 5, com 3 repetições, sendo cinco doses de CaCl2 (0,0; 0,5; 1,0; 2,0 e 4,0%), dois tipos de atmosferas (ambiente (AA) e modificada (AM)) e cinco avaliações. As avaliações foram acidez titulável (AT), sólidos solúveis (SS), relação SS/AT, pH, ácido ascórbico, incidência de podridão, perda de massa, aparência do engaço e índice de degrane. A AT, relação SS/AT, pH, incidência de podridão e perda de massa foram afetados tanto pela AM quanto pelo CaCl2. Os índices de degrane não foram afetados pelos tratamentos. No entanto, a aparência do engaço foi reduzida pela AM. A aplicação de CaCl2 associado à AM reduziu a perda de massa e a incidência de podridão e manteve o teor de ácido ascórbico. No segundo experimento uvas Isabel‟ provenientes de pomar comercial no Vale do Sirijí-PB foram colhidas em estádio de maturação comercial com o objetivo de avaliar o efeito de doses 1-MCP aplicadas durante 12 horas em caixas plásticas hermeticamente fechadas sob condições ambientes (252C e 752% de UR) durante armazenamento sob atmosfera modificada em temperatura ambiente. O experimento foi conduzido em delineamento inteiramente casualizado, em esquema fatorial 4 x 7, com 3 repetições, sendo quatro doses de 1-MCP (0; 500; 1000; e 2000 ppb) e sete avaliações (0, 2, 4, 6, 8, 10 e 12 dias). As avaliações foram acidez titulável (AT), sólidos solúveis (SS), relação SS/AT, pH, ácido ascórbico, antocianinas, coloração (Luminosidade, a*,b*,croma e H), incidência de podridão, perda de massa, firmeza, aparência do engaço e índice de degrane. SS, AT e incidência de podridão não sofreram influência do 1-MCP. Não foram verificados efeitos das doses testadas sobre SS/AT, luminosidade, croma e incidência de podridão. As doses de 1-MCP influenciaram no pH, manutenção do ácido ascórbico, aumento das antocianinas, aparência do engaço, perda de massa e manutenção da firmeza. O índice de degrane foi menor a medida que aumentaram as doses de 1-MCP aplicadas. O terceiro experimento avaliou-se uvas Isabel‟ produzidas no Vale do Sirijí-PB tratadas pós-colheita com quatro doses de 1-MCP (0; 500; 1000; e 2000 ppb) e mantidas sob atmosfera modificada em refrigeração (81C e 852% de UR) e após 18 dias transferidas para a condição ambiente… Advisors/Committee Members: Silvanda de Melo Silva.

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Objetivando avaliar a vida útil pós-colheita de melão tipo Charentais (Cucumis melo L.) sob refrigeração, submetidos à aplicação pós-colheita de 1MCP, associado ou não a atmosfera modificada (AM), foram conduzidos dois experimentos no Laboratório de Fisiologia e Tecnologia Pós-colheita da Embrapa Agroindústria Tropical em Fortaleza-CE, estudando características químicas e físicas de qualidade. Os frutos foram provenientes da Agroindústria Nolem Comercial Importadora e Exportadora Ltda, localizada no agropólo Mossoró Açu RN, Brasil. No primeiro experimento os frutos foram tratados com 600 nLL-1 de 1-MCP, em seguida, metade desses frutos foram embalados em filmes plásticos X-tend, mantendo-se frutos embalados sem aplicação de 1-MCP nas mesmas condições de armazenamento dos demais. Os melões foram armazenados por 27 dias sendo 21 dias (9 1 C e 85 5% U.R.), + 6 dias (25 2 C e 70 5% U.R.), simulando-se o período de comercialização, e avaliados nos seguintes tempos: 0, 7, 14, 21, 21+3 e 21+6 dias. O uso do 1-MCP, isoladamente, não se mostrou eficiente em manter a qualidade pós-colheita dos melões. A atmosfera modificada, isoladamente, foi eficiente em reduzir a perda de massa, manter melhor aparência externa e interna e maior ângulo Hue da casca, porém não sendo suficiente para retardar o amarelecimento dos frutos. Baseado na aparência externa, a vida útil pós-colheita dos frutos armazenados sob atmosfera modificada isolada e dos frutos tratados com 1-MCP e armazenados sob atmosfera modificada foi de 24 dias, enquanto que dos frutos tratados apenas com 1-MCP foi de 21 dias sob refrigeração. No segundo experimento os frutos foram tratados com 300 e 600 nLL-1 de 1-MCP, em seguida, metade desses frutos foram embalados em filmes plásticos, mantendo-se frutos embalados sem aplicação de 1-MCP nas mesmas condições de armazenamento dos demais. Os melões foram armazenados por 21 dias sendo 14 dias (9 1 C e 87 5% U.R.) + 7 dias (22 2 C e 70 5% U.R.). Em função da aparência externa, a vida útil pós-colheita dos frutos armazenados sob atmosfera modificada, com ou sem tratamento inicial de 1-MCP foi de 21 dias, enquanto que dos frutos tratados inicialmente apenas com 1-MCP, foi de 19 dias. A aplicação do 1-MCP proporcionou redução na atividade respiratória e na produção de etileno, e maior retenção da firmeza da polpa, menor perda de massa e melhor aparência externa quando associado a atmosfera modificada. A atmosfera modificada, isoladamente, foi eficiente em reduzir a perda de massa e manter melhor aparência externa.

Aiming to evaluate the postharvest shelf life of Charentais type melon (Cucumis melo L.) under refrigeration, submitted to the postharvest application 1MCP, associated or not to the modified atmosphere (AM), two experiments were carried out at the Laboratory of Physiology and Postharvest Tecnology of Embrapa Agroindústria Tropical in Fortaleza-CE, Brazil, studying chemical and physics quality characteristics. The fruits were originated from the Agroindústria Nolem Comercial Importadora e Exportadora Ltda, located at…

Advisors/Committee Members: Ricardo Elesbão Alves, Paulo Roberto Cecon, Maria Aparecida Nogueira Sediyama, Nilda de Fatima Ferreira Soares, Fernando Luiz Finger.

▼ United States ornamental plant producers imported approximately 61 million worth of unrooted cuttings in 2006. The top three greenhouse production crops geraniums (Pelargonium L'Hér. ex Ait.), poinsettias (Euphorbia pulcherrima Willd. ex Klotzsch) and New Guinea impatiens (Impatiens hawkeri W. Bull) had a wholesale value of 330 million and were produced from approximately 138 million cuttings. Understandably, improving cutting quality by reducing losses induced by ethylene exposure and shipping damage is an area of active research. To investigate possible areas for improvement in cutting production and shipping we studied the use of ethephon, [(2-chloroethyl) phosphonic acid] in stock plant management, 1-methylcyclopropene (1-MCP) use as an ethylene inhibitor of unrooted cuttings, and modified atmosphere (MA) storage of unrooted cuttings. Application of 700 mL • L-1 1-MCP prior to ethylene treatment prevented ethylene damage to Begonia hybrida 'Anita Louise', Portulaca oleracea L. 'Sleeping Beauty' and Lantana camara L. 'Patriot Sunbeam'. Also, 700 mL • L-1 1-MCP application to poinsettia 'Visions of Grandeur', impatiens 'Sonic Red', geranium 'Rocky Mountain White', Pelargonium peltatum (L.) L'Hérit. 'Mandarin', Petunia x hyrbrida 'Suncatcher coral prism' cuttings caused significant ethylene generation. 1-MCP application reduced geranium' Kardino' root numbers and delayed adventitious root formation of Angelonia angustifolia Benth. 'Carita Lavender', Calibrachoa x hybrida Llave & Lex. 'Terra Cotta', I. hawkeri 'Sonic Red', Portulaca oleracea L. 'Fairytales', Sutera cordata Kuntze 'Abunda Blue Improved' and Verbena x hybrida Groenl. & Ruempl. 'Aztec Wild Rose', though 1-MCP rooting effects were overcome by subsequent immediate exposure to ethylene. Ethephon is used to increase stock plant branching and sink tissues abscission. Ethylene evolution from cuttings harvested from recently treated stock plants is suspected to cause leaf abscission of unrooted cuttings during shipping. Impatiens 'Sonic Red' and 'Sonic White' cuttings harvested from stock plants treated with higher ethephon doses resulted in greater ethylene concentrations during storage. Cuttings harvested 24 hours after treatment with 0, 250, 500 or 1000 mg• L-1 ethephon produced 0.07, 1.3, 1.7 or 5.8 mg •L-1 • g-1 (fresh weight) ethylene in the first 24 hours of storage at 20 °C, respectively. Cuttings harvested 24 hours after treatment with 500 mg• L-1 ethephon stored at 10, 15, 20, and 25°C for 24 hours produced 0.37, 0.81, 2.03 and 3.55 mg • L-1 • g-1 (fresh weight) ethylene. Ethephon treatment effects were measurable on harvested cuttings up to 3 weeks post application. Modified atmosphere storage of impatiens 'Sonic Red', geranium 'Kardino' and poinsettia 'Visions of Grandeur' cuttings showed that cuttings held in 1:20 oxygen:carbon dioxide generated higher ethylene concentrations than any other treatment including atmospheric control. Cuttings stored in ratios… Advisors/Committee Members: Sylvia M. Blankenship, Committee Member (advisor), Lisa Oehrl Dean, Committee Member (advisor), Heike Winter Sederoff, Committee Member (advisor), John M. Dole, Committee Chair (advisor).

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Experiments were performed aiming to study the effect of controlled atmosphere (CA) and exogenous ethylene treatment on both the post-storage ripening and mealiness (woolliness) occurrence, evaluated both visually and objectively by the free juice content in the flesh of Chiripá peach fruits. Furthermore, the effect of inhibiting the ethylene action either in the beginning or in the end of CA storage on the incidence of physiological disorders and on the physical and chemical quality were also evaluated. In the first experiment, carried out both in 2005 and 2006, we evaluated: [1] cold storage (CS 21.0 kPa O2 + <0.5 kPa CO2); [2] CA with 1.0 kPa O2 + 3.0 kPa CO2; and [3] CA with 2.0 kPa O2 + 8.0 kPa CO2. In 2005, fruits were stored during 25, 30, and 35 days at -0.5C, whereas in 2006, storage was prolonged until 40 days. The second experiment evaluated the effect of exogenously applied ethylene in the storage room. The storage conditions were: [1] CS; [2] CS + exogenous ethylene (≈20 μL L-1); [3] CA (1.0 kPa O2 + 3.0kPa CO2); and [4] CA + exogenous ethylene. In the third trial, the effect of the ethylene action was assessed by the application of 1- methylcyclopropene (1-MCP - 900nL L-1), a potent inhibitor of the ethylene action. The treatments studied were: [1] CS + 1-MCP; [2] CA (2.0 kPa O2 + 8.0 kPa CO2); [3] CA + 1- MCP applied during the first 24 h of storage (P1); and [4] CA + 1-MCP applied during the first 24 h of post-storage ripening at 20C (P2). As the storage period was increased, the free juice contents decreased, independently of the storage condition. The flesh juiciness decreased sharply until 2 days of post-storage ripening at 20C, but increased again thereafter. This free juice restoration was both a storage period- and a storage condition-dependent process. CAstored fruits, especially in 2.0 kPa O2 + 8.0 kPa CO2, restored free juice contents faster. However, CS-stored fruits showed an abnormal pattern of ethylene synthesis, as the storage period was prolonged, a behavior that possibly led these fruits to restore their free juice contents to a lesser extend. Ethylene treatment during CS enhanced post-storage ethylene production and allowed fruits to restore juiciness at the same level as CA did. In addition to the ability of fruits in synthesize ethylene and to the effect of the presence of this gas, the ethylene action, during the post-storage ripening, was critical for the process of free juice restoration to occur. The application of 1-MCP, in the beginning of the CA storage, is the most promising technique for storing Chiripá peach fruits, because it allows both physical and chemical quality maintenance and avoids the dramatic decrease of flesh juiciness at the 2nd day after storage

Foram conduzidos experimentos objetivando avaliar o efeito da atmosfera controlada (AC) e da aplicação exógena de etileno sobre o amadurecimento e a ocorrência de lanosidade, avaliada visualmente e objetivamente pelo conteúdo de suco livre na polpa, em pêssegos Chiripá, após o armazenamento. Além disso,…

Advisors/Committee Members: Auri Brackmann, César Valmor Rombaldi, Fernando Teixeira Nicoloso.

▼ Os frutos são classificados em climatéricos e não climatéricos de acordo com o padrão da atividade respiratória e produção de etileno. No entanto, estudos apontam que alguns frutos não se enquadram nessa classificação e, a goiaba, tem sido considerada um deles. Uma vez que há divergências quanto à classificação de alguns frutos em climatéricos e não climatéricos, esse trabalho apresenta hipóteses de estudo para goiaba, pois dados sobre sua fisiologia pós-colheita ainda são contraditórios e para maracujá-amarelo, pois são poucos os dados sobre a sua fisiologia pós-colheita. Este trabalho teve como objetivo caracterizar a fisiologia do amadurecimento de maracujá-amarelo e goiaba \'Pedro Satoĺigados ou não às plantas, bem como, avaliar as respostas desses frutos à aplicação de reguladores do amadurecimento como o etileno e 1-metilciclopropeno (1-MCP). O trabalho foi conduzido em duas etapas. Na etapa 1, foi estimada a concentração endógena de CO2 e etileno de maracujás e goiabas ligados às plantas e em frutos colhidos em diferentes estádios de maturação. Foi fixado um tudo de silicone no epicarpo dos frutos ligados às plantas e coletadas amostras para CO2 e etileno desde o início do desenvolvimento até o completo amadurecimento dos mesmos e em frutos colhidos nos respectivos estádios de maturação para cada espécie frutífera, os quais foram analisados da mesma forma na pós-colheita. Na etapa 2, maracujás e goiabas foram submetidos à aplicação de 1-MCP e etileno e armazenados em câmara à 22ºC e 85% UR durante 9 dias e analisados a cada 3 dias quanto a acidez titulável, teor de sólidos solúveis e ácido ascórbico, rendimento de suco, firmeza, cor da casca, atividade respiratória, produção de etileno e atividade enzimática ACC oxidase. Não foi observado climatério para CO2 durante o amadurecimento de maracujás e goiabas ligados às plantas. O aumento da concentração endógena de CO2 foi observado apenas após a colheita dos frutos. A concentração endógena de etileno foi baixa enquanto os frutos estavam ligados às plantas. Maracujás que amadureceram na planta e sofreram abscisão natural mostraram aumento da concentração endógena de etileno dias antes da abscisão dos frutos. Para goiabas, houve aumento da concentração endógena de etileno somente após a colheita. Maracujás predominantemente verdes e verdes-amarelos responderam positivamente à aplicação de 1-MCP como retardador do amadurecimento, com manutenção da qualidade dos frutos, redução da atividade respiratória e diminuição da atividade da ACC oxidase. A diminuição da produção de etileno foi observada em frutos predominantemente verdes. Maracujás responderam ao etileno exógeno pela influência na qualidade física e química e apresentaram maior atividade enzimática principalmente em frutos predominantemente verdes. O etileno em goiabas verdeescuro promoveu o aumento da atividade respiratória, da produção de etileno e da atividade da ACC oxidase, podendo ser um dos fatores responsáveis pelo amadurecimento mais rápido dos frutos. Goiabas responderam positivamente ao 1- MCP,… Advisors/Committee Members: Angelo Pedro Jacomino, Jose Fernando Durigan, Joao Domingos Rodrigues, João Alexio Scarpare Filho, Diolina Moura Silva.

▼ The effects of AVG, an inhibitor of ethylene synthesis, in combination with MCP or heat treatment (HT) on quality traits of several apple cultivars after harvest (AH) or cold storage (ACS), and the involvement of ethylene in the regulation of SDH activity during the last weeks of fruit development were studied. AVG was applied to Royal Gala, Lodi, Senshu, Redchief Delicious and Red Fuji trees 4 weeks before normal harvest (H1). Control and AVG-treated (AVG) fruit were harvested at H1 and treated with MCP or air-heated. Fruit were ripened at room temperature (RT) AH or ACS. Some AVG fruit were harvested at H1 and 1 to 2 weeks after H1 (H2), or at H2 only. Ethylene production (EP), respiration rate (RR), firmness, starch index (SI), titratable acidity (TA), volatile production (VP) and AAT activity, among others, were measured AH and ACS. Peel and cortex of Gala were alcohol-fed and ester production quantified. EP and SDH presence and activity were measured at various harvest dates on control and AVG Lodi, Red Delicious and Fuji apples. AVG plus MCP was more effective in reducing HEP, RR, firmness and TA loss than either treatment alone; it did not provide further control on SI and did not repress Gala red skin color development more than AVG alone, though it consistently repressed VP. AVG plus HT was generally more effective than single treatments in reducing HEP, RR and firmness loss during storage. It was not different than the single treatments on TA, SI, and VP. The effect of AVG plus HT on fruit quality ACS was cultivar-dependent. AVG plus HT was not enough to maintain the quality of the earlyharvest cultivars, and it did not improve fruit quality of late-harvest cultivars. The effects of AVG plus MCP but not of AVG plus HT were evident at H2. Precursor availability was the major factor limiting VP, suggested by the low VP when RR was low, the increase in ester production in alcohol-fed samples, and the lack of correlation between AAT and ester production. SDH activity or expression was not affected by a reduction in ethylene production.

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O mamão é um fruto climatérico, cujas transformações resultantes do amadurecimento ocorrem rapidamente após a colheita. O tratamento com 1- metilciclopropeno (1-MCP) tem sido testado para ampliar sua vida útil, entretanto, com resultados até então pouco consistentes. Pesquisas com peras, bananas e ameixas foram realizadas utilizando conjuntamente 1-MCP e etileno, com resultados relevantes. Portanto, o objetivo deste trabalho foi estudar a fisiologia e a conservação pós-colheita do mamão Golden, submetido a diferentes combinações de 1-MCP e etileno, aplicados simultaneamente. Os frutos foram colhidos em pomares comerciais no estádio 1 de maturação, tratados e armazenados em câmaras frias a 11 e a 22ºC. O projeto foi dividido em três etapas. Na primeira etapa, observou-se que doses de 100 e 200 nL.L-1 de etileno combinados com iguais concentrações de 1-MCP, apresentaram resultados semelhantes aos do 1-MCP aplicado isoladamente. Na segunda etapa, o etileno nas concentrações entre 0 e 10 SL.L-1 foi combinado com 100 nL.L-1 de 1-MCP. Esse aumento na concentração de etileno diminuiu ou até mesmo anulou a ação do 1-MCP, nas concentrações mais elevadas. A mudança de cor e a perda da firmeza foram mais lentas nos tratamentos com 1-MCP na dose de 100 nL.L-1, aplicado sozinho ou associado a menor dose de etileno (2,5 SL.L-1). Estes mesmos tratamentos apresentaram atividade respiratória e produção de etileno menores que o controle. Na terceira etapa, os frutos tratados apenas com 1-MCP e 1-MCP mais etileno nas doses de 1 e 2,5 SL.L-1, mostraram maior retenção da firmeza externa, firmeza interna e cor da casca. A aparência também foi melhor nestes tratamentos, com menor porcentagem de frutos podres. O teor de sólidos solúveis foi semelhante em todos os tratamentos e o de ácido ascórbico foi mais elevado nos frutos tratados apenas com 1-MCP. A produção de etileno e a concentração de etileno endógeno foram maiores nos frutos que receberam apenas 1-MCP. A atividade respiratória e a concentração de CO2 endógeno mostraram pouca variação entre os tratamentos, durante o armazenamento. O teor de carotenóides foi menor nos tratamentos que receberam as maiores doses de etileno. O teor de clorofila foi maior no tratamento que recebeu apenas 1-MCP o qual levou mais tempo para tornar-se amarelo. A atividade da enzima pectinametilesterase (PME) foi menor nos tratamentos com 1-MCP e 1-MCP mais etileno na dose de 1 SL.L-1. A atividade das enzimas 1-aminociclopropano-1- carboxílico sintase (ACS) e oxidase (ACO) alternaram períodos de elevada e de baixa atividade em todos os tratamentos, durante o armazenamento. A aplicação simultânea de 1-MCP e do etileno mostrou resultados promissores no controle do amadurecimento do mamão Golden.

Papaya is a climacteric fruit which ripening resulting transformations occur rapidly after harvest. Treatment with 1-methylcyclopropene (1-MCP) has been tested to extend its shelf life, however, with inconsistent results so far. Researches with pears, bananas and plums were carried out using 1-MCP and…

Advisors/Committee Members: Angelo Pedro Jacomino, Daniel Manriquez Becerra, Ricardo Alfredo Kluge, Márcio Eduardo Canto Pereira, Eduardo Purgatto.

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O desenvolvimento de métodos para a conservação pós-colheita de framboesa in natura é de grande importância para a expansão da cultura no país, considerando que o principal entrave deste fruto é o curto período de comercialização. O presente trabalho teve como objetivo avaliar o efeito da aplicação de técnicas pós-colheita na conservação da qualidade de framboesa in natura, através do uso do armazenamento refrigerado, atmosfera modificada, aplicação pós-colheita do 1-metilciclopropeno (1-MCP) e aplicação pré e póscolheita de quitosana. Para isso, foram realizados seis experimentos. No primeiro, avaliou-se a melhor temperatura para a refrigeração dos frutos, sendo estes armazenados a 0, 5, 10 ou 15ºC e 90±5% de UR, por 12 dias (a melhor temperatura foi usada nos experimentos seguintes). O segundo experimento constituiu-se da utilização da atmosfera modificada passiva, armazenando os frutos, por 15 dias, em cloreto de polivinila (PVC - 15 m), polietileno de baixa densidade (PEBD - 10 e 20 m), polietileno de alta densidade (PEAD), polipropileno (PP - 10 m), politereftalato de etileno (PET) não perfurados e perfurados (sem modificação de atmosfera). No terceiro experimento, os frutos foram expostos ao 1-MCP a 0, 100, 500, 1000 e 2000 nL L-1, por 12 horas e, então, armazenados por 12 dias. No quarto experimento foi avaliado o comportamento dos frutos em resposta a aplicação pós-colheita de diferentes concentrações de quitosana. Os frutos foram imersos em soluções a 0, 0,5, 1 e 2%, por cinco minutos e, então, armazenados por 15 dias. No quinto experimento estudou-se a aplicação pré-colheita de quitosana, sendo toda a planta aspergida semanalmente, durante três semanas, nas mesmas concentrações do experimento anterior. Depois de colhidos, os frutos foram armazenados por 12 dias. No sexto experimento foi testada a associação das melhores técnicas pós-colheita estudadas nos experimentos anteriores, sendo que a sua ordem de aplicação resultou em diferentes tratamentos. Os frutos foram armazenados por 20 dias. A temperatura de 0ºC foi a mais indicada para a conservação e ampliação da vida útil de framboesas. A modificação da atmosfera resultante do uso do PEBD 10 m trouxe os melhores resultados na pós-colheita desse fruto. A aplicação do 1-MCP aliada à refrigeração não aumentou o período de comercialização da framboesa, mas manteve os frutos tratados com qualidade superior, sendo concentrações entre 1000 a 2000 nL L-1 as mais indicadas. O uso da quitosana aliada à refrigeração foi eficiente na manutenção da qualidade da framboesa, no entanto, apenas a aplicação na pós-colheita ampliou o período de comercialização. As melhores concentrações para a pré e pós-colheita foram 2 e 1%, respectivamente. A aplicação conjunta da refrigeração, filme plástico, 1-MCP e quitosana em pós-colheita amplia a vida útil do fruto, não importando a ordem de aplicação dos tratamentos.

The development of methods for maintaining fresh raspberry quality has great importance for the berry crop growth in Brazil, considering that the main…

Advisors/Committee Members: Ricardo Alfredo Kluge, Lucimara Rogeria Antoniolli, Angelo Pedro Jacomino.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

The objectives of this work were to evaluate the ethylene sensitivity of seven cut rose cultivars, to determine the ideal period of exposition, the best 1-MCP concentration, also the effect of multiple applications of 1-MCP on the quality of postharvest rose flowers. In the ethylene sensitivity experiment, the cultivars Grand Gala®, Versília, Texas, Konfetti , Tineke, Sandra and Vega, were exposed to five ethylene concentrations (0, 1, 10, 100 and 1000 µL L-1), in factorial 5x7 completely randomized design with six replicates. The Grand Gala® cultivar exhibited high ethylene sensitivity, with reduced life postharvest, while the Konfetti cultivar presented higher resistance to the effects of the ethylene. For the first 1-MCP experiment, the Grand Gala® and Konfetti cultivars were used in a factorial 3x5 completely randomized design with six replicates, regarding three exposition periods (3, 6 and 12 hours) and five concentrations of Ethylbloc® (0, 0.1, 0.5, 1.0 and 1.5 g/m3). For the Grand Gala® cultivar, the 1.5 g/m3 concentration of Ethylbloc® and period of exposition of 3 hours increased the flower longevity (7.2 days). The maximum leaf longevity was 5.1 days to 1.5 g/m3 concentration of Ethylbloc®. The greater flower development stage was 4.3 (several open petals), with 1.5 g/m3 Ethylbloc® concentration. For Konfetti cultivar, the 1.5 g/m3 concentration of Ethylbloc® and period of exposition of 3 hours promoted increase in the floral and leaf longevity to 12.1 and 10.8 days, respectively. The multiple 1-MCP application experiment was established in a completely randomized design with six replicates factorial 3x2, regarding three manners of application of the 1-MCP (once, twice and triple application) and two concentrations of Ethylbloc® (0 and 1.5 g/m3). The Grand Gala® and Konfetti cultivars treated with one 1-MCP application exhibited higher flower and leaf longevity compared with two and three applications.

Os objetivos deste trabalho foram de determinar a sensibilidade ao etileno de sete cultivares de rosa para corte, determinar o período ideal de exposição, a melhor concentração de 1-MCP e, o efeito de aplicações múltiplas de 1-MCP sobre a qualidade pós-colheita das hastes florais de rosa. Para o experimento de sensibilidade ao etileno exógeno, utilizou-se um delineamento inteiramente casualizado com seis repetições em esquema fatorial 5x7, referente a cinco concentrações de etileno (0, 1, 10, 100 e 1000 µL L-1) e sete cultivares de rosa. As cultivares Grand Gala®, Versília, Texas, Konfetti , Tineke, Sandra e Vega, foram expostas ao etileno por um período de 12 horas. As hastes florais da cultivar Grand Gala® apresentaram alta sensibilidade ao etileno, com reduzida vida pós-colheita, enquanto que hastes florais da cultivar Konfetti apresentaram…

Advisors/Committee Members: Finger, Fernando Luiz, Ribeiro Junior, José Ivo, Grossi, José Antônio Saraiva, Freitas, Gilberto Bernardo de, Rodrigues, Ernesto José Resende.

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Aiming to understand the mechanism of ripening of the Fuyu persimmon and extend the storage period, experiments were preformed to evaluate the effect of the period of exposure to low temperature, controlled atmosphere and inhibitor the ethylene action in the beginning or in the end of storage period on the incidence of softening. In the first experiment following treatments were evaluated: [1] 3 days at -0.5°C; [2] 6 days at -0.5°C; [3] 9 days at -0.5°C; [4] 6 days at 10°C; [5] 9 days at 10°C; [6] 15 days at 10°C; [7] 9 days at 15°C and [8] 15 days at 15°C. In the second experiment treatments were obtained by combining the temperature (-0.5; 10; 12.5; 15 e 17.5°C) with and without application of 1-methylcyclopropene (1-MCP), before storage. The laboratory tests were performed after 1 and 2 months storage. In the third experiment at -0.5ºC were evaluated the treatments: [1] cold storage(CS), [2] application of 1ppm of 1-MCP and subsequent CS, [3] CS and subsequent application of 1-MCP, [4] controlled atmosphere (CA) with 1.0kPa O2 + 8.0kPa CO2, [5] application of 1-MCP and subsequent storage in CA, [6] CA storage and subsequent application of 1-MCP. The laboratory tests were performed after 2 months in fruits storage in CS and after 4 months in fruits storage in CA. According to the results of the experiments the period of 9 days at -0.5ºC does not provide sufficient cooling to stimulate the maturation process of persimmon, do not altering the production of ethylene, respiration and softening of the fruit when compared with 15ºC. The storage of Fuyu persimmon for one month at -0.5ºC is sufficient to stimulate the maturation process, with 100% fruit softened after 6 days at 20°C. Already, storage for two months at -0.5°C accelerates the maturation process and leaving 100% fruit soft after 4 days at 20°C. At the temperatures of 10, 12.5 and 15°C occurred softening of fruit during storage, showing that these temperatures for long periods, are also efficient in the unlock process of maturation. The softening is related with the ethylene action and probably with its receptor. The application of 1-MCP before or after storage block the maturation process even in fruit exposed at -0.5°C, not occurring softening after exposure at 20°C. Controlled atmosphere delayed the softening. CA condition with 1.0kPa O2 + 8.0kPa CO2 with application of 1-MCP was the most efficient treatment to control the maturation, but occurred high incidence of decay after 4 months storage of Fuyu persimmon.

Objetivando compreender o processo de amadurecimento do caqui Fuyu e prolongar o armazenamento foram conduzidos experimentos para avaliar o efeito do período de exposição à baixa temperatura, atmosfera controlada e aplicação de inibidor da ação do etileno em dois momentos, no início e no final do armazenamento, sobre o amolecimento, analisados visualmente. No primeiro experimento avaliou-se: [1] 3 dias na temperatura de -0,5°C; [2] 6 dias na temperatura de -0,5°C; [3] 9 dias na temperatura de -0,5°C; [4] 6 dias na temperatura de 10°C; [5]…

Advisors/Committee Members: Brackmann, Auri, Saquet, Adriano Arriel, Steffens, Cristiano André.

▼ European pears are stored under controlled atmosphere (CA) and/or treated with 1-methylcyclopropene (1-MCP) to limit ripening and senescence. However, these practices can induce storage-related disorders in pears. A canonical powered-partial least squares analysis determined that senescent scald and internal breakdown in stored ‘AC Harrow Crisp’ pears were associated with decreased concentrations of ascorbate and accumulation of oxalate and gamma-aminobutyrate. These disorders and 1-MCP exacerbation of internal cavities were negatively correlated with total and reduced glutathione, reduced glutathione/oxidized glutathione and succinate. Internal cavities were associated with lactate accumulation, and negatively linked to malate depletion. Incidences of all three disorders increased with shelf-life in ‘Cold Snap’ pears following CA storage. Senescence-related disorders were reduced by 1-MCP and 2.5 kPa O2, whereas their impact on internal cavities was inconsistent across two years. Occurrence of these disorders was associated with high ethylene production rates, peel yellowing and fruit softening. Advisors/Committee Members: Bozzo, Gale (advisor), Shelp, Barry (advisor).

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES

The goal of this study was to evaluate the patulin contamination in post-harvest apples submitted to different storage conditions under controlled atmosphere (CA), in addition to apples and juices available in supermarkets. In relation to apples submitted to storage, two independent experiments were performed. The first experiment was conducted in a completely randomized 2x3 factorial, totaling six treatments with four replications. Factor A was presence and absence of 1-MCP. The factor B was: i) CA with 1.2 kPa O2 and 2.0 kPa CO2; ii) DCA with chlorophyll fluorescence measurement (ACD-FC); and iii) DCA with respiratory quotient monitoring (ACD-QR 1,3). The second experiment was also conducted in a completely randomized design, totaling three treatments with four replicates. The conditions were: i) CA with 1.2 kPa O2 and 2.0 kPa CO2; ii) DCA-CF; and iii) DCA-RQ 1.3. In both experiments were used fruits from commercial orchards of the Vacaria - RS city, being stored for nine months in the mentioned conditions plus seven days of exposure at 20 °C to simulate the shelf life. Afterwards, the fruits were submitted to the analysis: decay incidence, percentage of healthy fruits and patulin occurrence. In addition, contamination with patulin was evaluated in apples and juices commercially available in supermarkets in all regions of the Santa Maria - RS city. Analytical method for patulin determination in apples and apple juice was developed and validated in CEPARC. In this method, samples were extracted with acidified ethyl acetate followed by the addition of Na 2SO4. The cleanup step uses silica and Na2 SO4). The solvent was evaporated at 65 °C and residue dissolved in acetonitrile: water (75:25). The analytical technique employed was UPLC-MS/MS. The results showed that the studied conditions of CA and DCA were not efficient to prevent the production of patulin, in both the 'Galaxy' and 'Fuji Kiku' apples, under the conditions studied in addition to 7 days exposure at 20 ºC. Healthy fruits were not contaminated with patulin present in fruits with rot. For apples 'Galaxy', the application of 1-MCP increased the percentage of fruits with rot and the patulin concentration, being not advantageous its application in this cultivar. In the 'Fuji Kiku' apples there was no significant difference between CA and DCA-CF and DCA-RQ 1.3 in the patulin concentration, although all the fruits of this cultivar showed patulin contamination even though values lower than the LMT of 50 μg kg-1. The apple and apple juice samples monitoring collected in supermarkets evidenced the presence of patulin in both matrices, with concentrations ranging from <LOQ (25 μg kg-1) to 754.4 μg kg-1, showed samples with concentrations well above the limit established by Brazilian legislation. Future studies are needed to increase the apple conservation potential, related to the new techniques of DCA (CF and RQ) and 1-MCP application in the rot determination and patulin contamination, because…

Advisors/Committee Members: Pizzutti, Ionara Regina, Brackmann, Auri, Fogaça, Aline de Oliveira.

▼ Low photosynthetic photon flux density (PPFD) during certain growth periods of cotton (Gossypium hirsutum L.) has been shown to impact yield, ethylene synthesis, and fiber quality. Previous research with shading has shown that lint yield can be significantly reduced in the latter stages of growth. This two-year field study was conducted at the Texas A&M AgriLife Research Farm in Burleson County, Texas, in 2008 and 2009. The study evaluated the impact of an 8-day period of shade (63 percent reduction of PPFD) on cotton yield parameters, fiber quality, and the impact of 1-methylcyclopropene (1-MCP), an ethylene inhibitor, to alter detrimental cotton responses when applied as a foliar spray under shaded and non-shaded conditions. Shade and 1-MCP were imposed at four developmental stages of growth: pinhead square (PHS), first flower (FF), peak flower (PF), and boll development (BD). Data pooled over both years indicated that there were no significant differences in yield for 1-MCP treatments; however, numerical differences existed. Shade applied during the BD stage of development showed significantly lower yield than the untreated control. These results showed a decline in seed cotton and ginned seed cotton by 522 and 207 kg ha-1, respectively. To further analyze further yield components, box-mapping was conducted during both years. However, this data failed to explain consistent patterns of the observed yield responses. Data was also collected to determine the amount of fibers per seed and seed weights. Cotton fiber data did not show consistent correlations with the numerical increases and significant decreases in yield. Electrolyte leakage and stomatal conductance data also were collected. Electrolyte leakage showed no statistical differences when compared to the untreated control. Stomatal conductance measurements showed no consistency for treatments during both years. Advisors/Committee Members: Cothren, J. Tom (advisor), Senseman, Scott A. (committee member), Reed, David W. (committee member).

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Experiments were performed aiming to study the effect of controlled atmosphere (CA) and exogenous ethylene treatment on both the post-storage ripening and mealiness (woolliness) occurrence, evaluated both visually and objectively by the free juice content in the flesh of Chiripá peach fruits. Furthermore, the effect of inhibiting the ethylene action either in the beginning or in the end of CA storage on the incidence of physiological disorders and on the physical and chemical quality were also evaluated. In the first experiment, carried out both in 2005 and 2006, we evaluated: [1] cold storage (CS 21.0 kPa O2 + <0.5 kPa CO2); [2] CA with 1.0 kPa O2 + 3.0 kPa CO2; and [3] CA with 2.0 kPa O2 + 8.0 kPa CO2. In 2005, fruits were stored during 25, 30, and 35 days at -0.5°C, whereas in 2006, storage was prolonged until 40 days. The second experiment evaluated the effect of exogenously applied ethylene in the storage room. The storage conditions were: [1] CS; [2] CS + exogenous ethylene (≈20 μL L-1); [3] CA (1.0 kPa O2 + 3.0kPa CO2); and [4] CA + exogenous ethylene. In the third trial, the effect of the ethylene action was assessed by the application of 1- methylcyclopropene (1-MCP - 900nL L-1), a potent inhibitor of the ethylene action. The treatments studied were: [1] CS + 1-MCP; [2] CA (2.0 kPa O2 + 8.0 kPa CO2); [3] CA + 1- MCP applied during the first 24 h of storage (P1); and [4] CA + 1-MCP applied during the first 24 h of post-storage ripening at 20°C (P2). As the storage period was increased, the free juice contents decreased, independently of the storage condition. The flesh juiciness decreased sharply until 2 days of post-storage ripening at 20°C, but increased again thereafter. This free juice restoration was both a storage period- and a storage condition-dependent process. CAstored fruits, especially in 2.0 kPa O2 + 8.0 kPa CO2, restored free juice contents faster. However, CS-stored fruits showed an abnormal pattern of ethylene synthesis, as the storage period was prolonged, a behavior that possibly led these fruits to restore their free juice contents to a lesser extend. Ethylene treatment during CS enhanced post-storage ethylene production and allowed fruits to restore juiciness at the same level as CA did. In addition to the ability of fruits in synthesize ethylene and to the effect of the presence of this gas, the ethylene action, during the post-storage ripening, was critical for the process of free juice restoration to occur. The application of 1-MCP, in the beginning of the CA storage, is the most promising technique for storing Chiripá peach fruits, because it allows both physical and chemical quality maintenance and avoids the dramatic decrease of flesh juiciness at the 2nd day after storage

Foram conduzidos experimentos objetivando avaliar o efeito da atmosfera controlada (AC) e da aplicação exógena de etileno sobre o amadurecimento e a ocorrência de lanosidade, avaliada visualmente e objetivamente pelo conteúdo de suco livre na polpa, em pêssegos Chiripá , após o armazenamento. Além disso,…

Advisors/Committee Members: Brackmann, Auri, Nicoloso, Fernando Teixeira, Rombaldi, César Valmor.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES

The larger quality problem of table grape is related to the ease berry drop or abscission of berries after harvest of clusters, due to the development of the abscission zone. This study aimed to evaluate the effect of calcium chloride (CaCl2) and 1-MCP (1-methylcyclopropene), on postharvest conservation under different storage conditions of Isabel‟ grape, produced in the Sirijí Valley (PE/PB), conducted in three experiments. In The first experiment Isabel‟ grapes produced at Natuba, Sirijí Valley-PB, Brazil, were treated postharvest with calcium chloride (CaCl2) and modified atmosphere (MA) aiming to evaluate the quality maintenance during storage at 12±1 °C and 85±2% RH. The experiment was carried out in a completely randomized design, in a factorial scheme 5 x 2 x 5 with three replications, with five doses of CaCl2 (0,0; 0,5; 1,0; 2,0 and 4,0%), two types of atmosphere (room and modified) and five evaluations. The evaluations were soluble solids (SS), titratable acidity (TA), SS/TA ratio, pH, ascorbic acid, decay incidence, rachis appearance, and berry drop index. TA, ratio SS/TA, pH, incidence of decay, and mass loss were influenced by both MA and CaCl2. Berry drop index was not affected by treatments. However, rachis appearance was maintained by MA. The application of CaCl2 associated with MA reduced the mass loss and incidence of decay, and kept ascorbic acid content. In the second experiment Isabel‟ grapes from a commercial orchard in the Sirijí Valley - PB were harvested at commercial maturity with the aim of evaluating the effect of doses 1-MCP applied during 12 hours in sealed plastic boxes under room conditions (25 ± 2 ° C and 75 ± 2% RH) during storage under modified atmosphere at room temperature. The experiment was carried out in a completely randomized design, in factorial scheme 4 x 7, with three replications, with four doses of 1-MCP (0, 500, 1000, and 2000 ppb) and seven evaluations (0, 2, 4, 6, 8, 10 and 12 days). The evaluations were soluble solids (SS), titratable acidity (TA), SS/TA ratio, pH, ascorbic acid, anthocyanins, coloration (Lightness, a *, b *, chroma and ° H), incidence of decay, mass loss, firmness, rachis appearance, and berry drop index. The SS, AT, SS/TA, L, Chroma, and incidence of decay were not affected by 1- MCP. The doses of 1-MCP influenced on pH, retention of ascorbic acid, increase of anthocyanins, rachis appearance, lower mass loss, and maintenance of firmness. The berry drop index decreased as the doses of 1-MCP applied increased.…

Advisors/Committee Members: Silva, Silvanda de Melo.

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UV-C radiation is utilized in postharvest of fruits with the objective of reducing inoculum and disease incidence. However, it is possible that it acts as an abiotic stressor agent, activating defense mechanisms of plant tissues, which is characterized by the induction of secondary metabolism, especially through the synthesis of phenolics compounds and carotenoids, involved in the protection of oxidative stress. In this context, molecular changes derived from the action of UV-C radiation were evaluated in tomato, during storage (20-23°C), and its relationship with biochemical and physiological responses and with events influenced by the plant hormone ethylene. For such, the following treatments were performed: UV-C at 3,7 kJ m-2; 1-methylcyclopropene (1-MCP) at 2 ppm, and 1-MCP + UV-C. From these treatments it was observed that a reduction in fruit firmness occurred in untreated and UV-C treated fruit as maturation advanced, accompanied by the accumulation transcripts of a gene encoding the enzyme polygalacturonase (PG), indicating that UV-C treatment did not contribute for the maintenance of this quality attribute. On the other hand, 1-MCP participated in the maintenance of flesh firmness, even though PG transcript accumulation was found, suggesting this gene is not the primary responsible for this property. UV-C radiation induced an increase in ethylene content, but still, a delay in fruit color development occurred in fruit from this treatment. As expected, 1-MCP treated fruit showed a delayed peak of ethylene production, of the color development, and of decrease in flesh firmness. Lycopene content was lower in fruit subjected to 1-MCP treatment. However, in fruit treated with 1-MCP + UV-C, β-carotene content was significantly higher in the exocarp of the fruit, which conferred them an orange color. p-Hydroxybenzoic acid was the predominant phenolic compound found in exocarp and mesocarp, and quercetin was found in higher content in fruits subjected to 1-MCP + UV-C treatment. δ-tocopherol was the only tocopherol identified in tomato fruit, present in high levels in the exocarp of the fruit. Genes coding for enzymes responsible for synthesis of carotenoids, phytoene synthase (PHS) and δ-carotene desaturase (ZCD) for the synthesis of phenylpropanoids, phenylalanine ammonia lyase (PAL) and chalcone synthase (CHS), antioxidant enzymes, catalase (CAT) and superoxide dismutase (SOD) showed initially high accumulation of transcripts in the exocarp and later in the mesocarp of fruit subjected to UV-C radiation. In general, UV-C radiation induced ethylene production, and yet slowed down maturation, particularly regarding color changes. Flesh firmness was not affected by UV-C treatment. Molecular responses to UV-C radiation application started in the exocarp and were in sequence found in the mesocarp.

A radiação…

Advisors/Committee Members: CPF:44074271087, http://lattes.cnpq.br/0102364512482073, Rombaldi, César Valmor.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Aiming to evaluate the postharvest shelf life of Charentais type melon (Cucumis melo L.) under refrigeration, submitted to the postharvest application 1 MCP, associated or not to the modified atmosphere (AM), two experiments were carried out at the Laboratory of Physiology and Postharvest Tecnology of Embrapa Agroindústria Tropical in Fortaleza-CE, Brazil, studying chemical and physics quality characteristics. The fruits were originated from the Agroindústria Nolem Comercial Importadora e Exportadora Ltda, located at Mossoró Açu RN agropole, Brazil. In the first experiment the fruits were treated with 600 nL·L-1 of 1-MCP, half of those fruits was wrapped in X-tend plastic films (staying fruits wrapped without application of 1-MCP in the same conditions of the others). The melons were stored by 27 days being 21 days (9 ± 1 ºC and 85 ± 5% U.R.), + 6 days (25 ± 2 ºC and 70 ± 5% U.R.), being simulated the commercialization period, and evalueted in the following times: 0, 7, 14, 21, 21+3 and 21+6 days. The use of the 1-MCP, separately, was not shown efficient in maintaining the postharvest quality of the melons. The modified atmosphere, separately, it was efficient in reducing the weight loss, to maintain better external and internal appearance and larger peel Hue angle, however not being enough to delay the yellowish of the fruits. Based on the external appearance, postharvest shelflife of the fruits stored under isolated modified atmosphere and of the treated fruits with 1-MCP and stored under modified atmosphere it was of 24 days, while of the treated fruits just with 1-MCP was 21 days under refrigeration. In the second experiment the fruits were treated with 300 and 600 nL·L-1 of 1-MCP, half of those fruits was wrapped in plastic films, staying fruits wrapped without application of 1-MCP in the same conditions of storage of the others. The melons were stored by 21 days being 14 days (9 ± 1 ºC and 87 ± 5% U.R.) + 7 days (22 ± 2 ºC and 70 ± 5% U.R.). In function of the external appearance, postharvest shelflife of the fruits stored under modified atmosphere, with or without initial treatment of 1-MCP it was 21 days, while of the treated fruits initially just with 1-MCP, it was 19 days. The application of the 1-MCP provided reduction in the breathing activity and ethylen production, and larger flesh firmness retention, smaller weight loss and better external appearance when associated the modified atmosphere. The modified atmosphere, separately, it was efficient to reduce the weight loss and to maintain better external appearance.

Objetivando avaliar a vida útil pós-colheita de melão tipo Charentais (Cucumis melo L.) sob refrigeração, submetidos à aplicação pós-colheita de 1 MCP, associado ou não a atmosfera modificada (AM), foram conduzidos dois experimentos no…

Advisors/Committee Members: Alves, Ricardo Elesbão, Cecon, Paulo Roberto, Finger, Fernando Luiz, Sediyama, Maria Aparecida Nogueira, Soares, Nilda de Fatima Ferreira.

▼ Vegetative annuals are currently popular in the ornamental horticulture industry. Many crops are newly domesticated species and little is known about how they perform during shipping or in the retail environment. Nine species and 21 cultivars were grown and underwent simulated shipping after harvest or nitrogen toning two weeks before harvest. Shipping was not found to affect the number of flowers on all but two cultivars post ship. Nitrogen toning affected vegetative growth of most Bracteantha bracteata (bracteantha) cultivars at harvest. All species had an effect due to toning postharvest. Bractenatha and Diascia ×hybrida (diascia) were chosen for further study due to their performance during these experiments. The effect of thidiazuron (TDZ) as a foliar spray and nitrogen toning on leaf yellowing and plant growth of bracteantha were evaluated. The two treatments were then combined to see how the two treatments worked together. It was found TDZ decreased leaf yellowing but its effects can be negated if the plants were not toned. Nitrogen toning reduced vegetative growth of the bracteantha without affecting the number of flowers on the plants. Diascia was found to have flower abscission in response to shipping. Further trials were conducted using 1- methylcyclopropene (1-MCP) an ethylene inhibitor. The effects of shipping duration and temperature were investigated. 1-MCP was found to hold flowers on treated plants longer postharvest than those not treated. Plants shipped for one day had no differences from the control but shipping for two days had a negative effect on plant quality. Postharvest shelf life was decreased when diascia was shipped at 24 °C when compared to cooler shipping temperatures. These results indicate shipping for no longer than one day and at less than 24 °C is recommended for diascia. Advisors/Committee Members: Starman, Terri W (advisor), Heinz, Kevin M (committee member), Pemberton, H. Brent (committee member).

▼ [EN] Persimmon (Diospyros kaki L.) 'Rojo Brillante' is an astringent variety characterised by good growing conditions, excellent colour, size, sensory characteristics and good nutritional properties. In the last decade, its production has grown substantially in Spain given the application of high levels of CO2 to remove astringency while firmness is preserved. This technology has also increased its potential as a fresh-cut commodity. However, physical damage during processing result in degradation of the colour and firmness of the product and a higher susceptibility to microbial spoilage that significantly reduces the fruit's shelf life. The objective of the present thesis was to develop optimum procedures for processing and marketing 'Rojo Brillante' persimmon into a fresh-cut product with the maximum shelf life and best physicochemical, nutritional, sensory and microbiological quality. Firstly, the objective was to evaluate the effect of the maturity stage (MS) at harvest, storage time at 15 ºC before processing, and the application of different antioxidant treatments on enzymatic browning, sensory and nutritional quality of fresh-cut 'Rojo Brillante' persimmon during storage at 5 ºC. Concentrations of 10 g L-1 ascorbic acid (AA) or 10 g L-1 citric acid (CA) controlled tissue browning and maintained the visual quality of fresh-cut persimmon above the limit of marketability for 6-8 storage days at 5 ºC, depending on the MS. However, these acidic solutions reduced fruit firmness as compared to control samples. Further studies showed that the combination of these antioxidants with 10 g L-1 CaCl2 maintained firmness of the persimmon slices within the same range as the control samples. In another work, the application of 1-methylcyclopropene (1-MCP) allowed to process fruits after 45 days of storage at 1 ºC with commercial firmness and the antioxidant solution (10 g L-1 CA + 10 g L-1 CaCl2) extended the limit of marketability up to 9 days of storage at 5 ºC. Different controlled atmosphere conditions in combination with AA or CA dips were also evaluated as a first step to select optimum O2 and CO2 concentrations for modified atmosphere packaging (MAP) of fresh-cut 'Rojo Brillante' persimmons. Overall, the combination of antioxidant dips and a controlled atmosphere composed of 5 kPa O2 (balance N2) was proved to be the most effective combination to control enzymatic browning. This atmosphere maintained the visual quality of persimmon slices within the limit of marketability during 7- 9 days at 5 ºC. On the contrary, high CO2 concentrations (10 or 20 kPa) induced darkening in some tissue areas, associated with a flesh disorder known as 'internal flesh browning'. Later studies confirmed the beneficial effect of an active MAP in 5 kPa O2 compared to passive MAP to improve the visual quality of fresh-cut 'Rojo Brillante' persimmon, showing a synergic effect with the antioxidant dip (10 g L-1 CA + 10 g L-1 CaCl2). Antioxidant edible coatings were prepared from whey protein isolate (WPI), soy protein isolate (SPI),… Advisors/Committee Members: Perez Gago, Bernardita (advisor).

▼ The aim of this thesis was to investigate how 1-methylcyclopropene (1-MCP) affects ëConferenceí pears. The treatment with 1-MCP was very effective to reduce ripening and senescence but can result in a permanent inhibition of ripening. This ripening blockage was associated with a high concentration of 1-MCP (600 ppb) whereas a lower concentration (300 ppb) gave very variable results. This behaviour was mainly influenced by the harvest maturity and especially by the ability of the fruit to produce ethylene at the moment of treatment. The softening behaviour and the effectiveness of 1-MCP are determined by physiological parameters related principally with the ethylene metabolism and is determined by the extent of the inhibition of ACC synthase during cold storage and the reactivation of the enzyme during shelf life. 1-MCP treatment also allows a better maintenance of the fruitís antioxidant system. Finally, this thesis proposes a system that permits the prevention of the evergreen behaviour. The combination of a high dose of 1-MCP and ethylene applied simultaneously immediately after harvest permitted a considerable delay of the ripening process without completely blocking it and resulted in a homogenization of ripening between fruit from different harvest dates. Advisors/Committee Members: false (authoremailshow), Recasens Guinjuan, Inmaculada (director), false (authorsendemail).

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A banana é um fruto climatérico que apresenta alta taxa respiratória e alta produção de etileno após a colheita, o que a torna altamente perecível. Acredita-se que o 1-MCP é capaz de ligar-se ao receptor do hormônio etileno, bloqueando sua ação e, consequentemente, retardando o amadurecimento do fruto. Bananas (Musa acuminata AAA cv. Nanicão) com aproximadamente 110 dias pós-antese foram armazenadas em condições controladas de umidade e temperatura. Parte da amostra foi tratada com 1-MCP (100 nl/L), outra parte foi tratada com etileno (100 ppm - 7L/min), e, uma terceira parte, foi mantida como controle. Os frutos foram caracterizados, durante o período de amadurecimento, em relação à produção de etileno e CO2 (por cromatografia à gás), à concentração de amido (pelo método enzimático descrito por Cordenunsi e Lajolo 1995) e açúcares (glicose, frutose, sacarose e maltose - por HPLC-PAD). Também foram analisados os comportamentos das enzimas α e β- amilases, fosforilase, DPE 1 e DPE 2 por atividade enzimática in vitro ou por P.A.G.E. nativo e, quando possível, foram avaliados os comportamentos destas enzimas frente a tradução (Western blotting) e transcrição proteica (Northern blotting). A degradação de amido, assim como a respiração, a produção de etileno e síntese de açúcares foram retardadas nos frutos tratados com o 1-MCP. Como consequência destas mudanças, também houve uma alteração nos perfis das atividades enzimáticas. Os resultados indicaram que o 1-MCP, além de atrasar o climatério respiratório, foi capaz de provocar descompasso no padrão de degradação de amido e síntese de açúcares sugerindo também que outros fatores temporais, necessários ao processo, foram prejudicados. Dentre as enzimas envolvidas no metabolismo de carboidratos de bananas, as α-amilases não demonstraram ser etileno-dependentes (?) as β-amilases mostraram ser enzimas bastante dependentes do etileno e parecem ter importância especial quando se trata do metabolismo da maltose, em conjunto com a DPE 2; atividade fosforolítica foi induzida ao longo do amadurecimento, mas parece ter resposta mais significativa a alterações basais do hormônio etileno e, portanto, sugere-se que esta enzima esteja envolvida com mais de uma forma de regulação; a DPE 1 apresentou maior atividade ao início da degradação do amido, indicando sua atuação sobre glicanos liberados pelas α-amilases. A presença de DPEs na banana torna o seu metabolismo de carboidratos mais próximo daquele presente em folhas.

Banana is a climateric fruit that has a high respiration rate and a high ethylene production after harvest, what makes this fruit very perishable. It is believe that 1- MCP is capable to interact with the hormone ethylene receptors, blocking its action and, as result, delaying the fruit ripening. Bananas (Musa acuminata AAA cv. Nanicão) with 110 days after anthesis were stored in controlled conditions of umidity and temperature. Part of the sample was treated with 1-MCP (100 nl/L), another part was treated with ethylene (100 ppm -…

Advisors/Committee Members: Franco Maria Lajolo, Eduardo Purgatto, Antonio Vargas de Oliveira Figueira, Angelo Pedro Jacomino, Carlos Alberto Labate, Eduardo Purgatto.