ABSTRACT The objective of this work was to evaluate the effect of pre-storage fruit treatment with nitric oxide (NO) on the quality maintenance of cold stored ‘Cripps Pink’ apples. The following treatments were evaluated: 0 μL·L–1 of NO (control); 10 μL·L–1 of NO for 2 h; 10 μL·L–1 of NO for 4 h; 10 μL·L–1 of NO for 8 h; and 20 μL·L–1 of NO for 2 h. Fruit treated with NO, regardless of concentration and application time, had a greener skin background color than the control, especially those treated with 10 μL·L–1 for 8 h. After 7 days of shelf life (23 ± 3 °C/relative humidity, RH, of 65 ± 5%), fruit treated with 10 μL·L–1 for 8 h and 20 μL·L–1 for 2 h had lower respiration rate and a greener skin background color than the control. Fruit treated with NO, regardless of concentration and application time, had a lower incidence of flesh browning after storage. The use of NO (10 μL·L–1 applied for 8 h and 20 μL·L–1 applied for 2 h) pre-storage maintains the quality of ‘Cripps Pink’ apples, because it delays skin yellowing and reduces flesh browning. Nitric oxide has no effect on the maintenance of flesh firmness in ‘Cripps Pink’ apples.

Resumo O objetivo deste trabalho foi avaliar o efeito da atmosfera modificada (AM) e do tratamento com 1-MCP em baixa temperatura de armazenamento (1,5 °C) e do tratamento com 1-MCP em elevada temperatura de armazenamento (8,0 °C) sobre a qualidade de ameixas ‘Laetitia’, especialmente sobre o escurecimento da polpa. Os tratamentos avaliados foram 1,5 °C; 1-MCP (1,0 µL L-1) + 1,5 °C; 1,5 °C + AM; 1-MCP + 1,5 °C + AM; 8,0 °C; e 1-MCP + 8,0 °C. Os frutos foram armazenados por 30 e 40 dias e, após, mantidos por mais três dias em condições ambiente. Na temperatura de 1,5 °C, o 1-MCP associado à AM manteve maior firmeza de polpa e a coloração da casca menos avermelhada e reduziu o escurecimento de polpa, em relação aos demais tratamentos a 1,5 °C, em ambos os períodos de armazenamento. Em frutos não tratados com 1-MCP e armazenados na temperatura de 8,0 °C, não houve escurecimento de polpa, em ambos os períodos de armazenamento, porém os frutos apresentaram menor firmeza de polpa e a cor da casca e da polpa mais vermelhas, em relação à temperatura de 1,5 °C. O uso de 1-MCP em frutos armazenados a 8,0 °C retardou essas alterações de firmeza de polpa e da cor da casca e da polpa aos 30 dias de AR, seguidos por mais 3 dias em condições ambiente. A AM, independentemente da aplicação de 1-MCP, causou acúmulo de acetaldeído, aos 30 dias de armazenamento, e de etanol aos 30 e 40 dias de armazenamento a 1,5 oC. O uso de 1-MCP a 1,5 °C reduziu a produção de acetato de etila, acetaldeído e etanol sem AM. Frutos armazenados a 8,0 °C, independentemente da aplicação de 1-MCP, apresentaram menor acúmulo de acetaldeído e de etanol.

Abstract The objective of this study was to evaluate the effect of modified atmosphere (MA) and 1-methylcyclopropene (1-MCP) treatment on low storage temperature (1.5 °C) and 1-MCP treatment on high storage temperature (8.0 °C) on fruit quality of ‘Laetitia’ plums, mainly on internal browning. The treatments evaluated were 1.5 °C; 1-MCP (1.0 µL L-1) + 1.5 °C; MA + 1.5 °C; 1-MCP + MA + 1.5 °C; 8.0 °C; 1-MCP + 8.0 °C. Fruit were stored for 30 and 40 days, followed by three day of shelf life. For fruit stored at 1.5 °C, the treatment with 1-MCP associated to MA provided higher flesh firmness, less intense skin red color and reduced occurrence of internal browning in comparison to the fruit stored at 1.5 °C of the remaining treatments, for both periods of storage. In fruit not treated with 1-MCP and stored at 8.0 °C there was no occurrence of internal browning, despite of lower flesh firmness and more intense red color of the skin and flesh in comparison to the fruit stored at 1.5 °C. The treatment with 1-MCP in fruit stored at 8.0 °C delayed those changes of flesh firmness and red color of the skin and flesh assessed after 30 days of storage, followed by three days of shelf life. The MA, regardless of 1-MCP treatment, had fruit with higher production of acetaldehyde after 30 days of storage, and ethanol after 30 and 40 days of storage at 1.5 oC. In fruit stored at 1.5 °C without MA, the treatment with 1-MCP reduced the production of ethyl acetate, acetaldehyde and ethanol. Fruit stored at 8.0 °C, regardless of 1-MCP treatment, had the lowest production of acetaldehyde and ethanol.

ABSTRACT: This study evaluated the leaf area index (LAI) recovery mechanisms and forage accumulation rates on the regrowth of different grass species subjected to different defoliation intensities. For that purpose, plots of Pennisetum clandestinum (kikuyugrass), Lolium multiflorum (annual ryegrass), and Avena strigosa (black oats) were defoliated from 20 to 80 % of their initial heights (25, 20, and 25 cm, respectively). At different increments in height, forage samples were collected to ground level and used to estimate tiller population density (TPD), leaf area per tiller (LA), and forage mass. From these data, we calculated the leaf area index (LAI), average leaf area index (aLAI), and average and instantaneous forage accumulation rate (FAR and IFAR, respectively). Data were plotted over time (days) to describe LAI recovery and forage accumulation rates. As the defoliation intensity increased, greater canopy heights were needed for pastures to achieve their maximum forage accumulation rates, which required longer regrowth intervals. The need for high tiller recruitment after defoliation, which delayed canopy LAI recovery, seemed to be one of the main cause. Thus, grazing management strategies that involve costly tiller recruitment could decrease both overall forage production and sward persistence over time. However, the plant ability to recover LAI after successive intense defoliations seems to be species-dependent and related to their phenotypic plasticity.

O objetivo deste trabalho foi avaliar o acúmulo de forragem, a estrutura do dossel, o valor nutritivo, o consumo de forragem e a produção animal, em pastos de Urochloa humidicola sob lotação contínua. As cultivares BRS Tupi e Comum foram avaliadas durante os períodos de seca e das águas (julho de 2011 a agosto de 2012), em delineamento experimental de blocos ao acaso, com dois tratamentos e seis repetições. Mensalmente, os animais foram pesados e os pastos amostrados para a determinação de: taxa de acúmulo de forragem (TAF); massa de forragem; percentagens de folha (PF), colmo e material morto (PM); e valor nutritivo. O consumo de matéria seca (CMS) foi determinado uma vez a cada período. 'BRS Tupi' apresentou maiores TAF e PF e menor PM do que a 'Comum', durante o período das águas. O valor nutritivo, o CMS e o ganho médio diário foram semelhantes entre as duas cultivares. O conteúdo de proteína bruta da forragem - 6,0 e 5,0%, respectivamente, para os períodos das águas e seco - foi o principal fator limitante ao CMS. 'BRS Tupi' recebeu maior taxa de lotação e, consequentemente, possibilitou maior ganho de peso vivo por área (192 kg ha-1 por ano) do que a 'Comum' (126 kg ha-1 por ano). A 'BRS Tupi' é uma boa alternativa para a diversificação de pastagens em solos de baixa fertilidade sujeitos a alagamento temporário.

The objective of this work was to evaluate forage accumulation, canopy structure, nutritive value, forage intake, and animal production in pastures of Urochloa humidicola under continuous stocking. The cultivars BRS Tupi and Comum were evaluated during the drought and wet periods (July 2011 to August 2012), in a randomized complete block experimental design, with two treatments and six replicates. Monthly, the animals were weighted and the pastures sampled for the determination of: forage accumulation rate (FAR); forage mass; percentages of leaves (PL), culms, and dead material (DL); and nutritive value. Forage intake (FI) was determined once a period. 'BRS Tupi' had a higher FAR, PL, and DL than 'Comum', during the wet period. The nutritive value, FI and the daily weight gain were similar between both cultivars. Forage protein content - 6.0 and 5.0%, for the wet and drought periods, respectively - was the main limiting factor for FI. 'BRS Tupi' had higher stocking rates and, consequently, made possible a higher live weight gain per area (192 kg ha-1 per year) than 'Comum' (126 kg ha-1 per year). 'BRS Tupi' is a good alternative for diversification of pastures in soils with low fertility that are temporarily subjected to flooding.

O objetivo deste trabalho foi identificar os atributos fisiológicos, físico-químicos e minerais associados à ocorrência pós-colheita de "bitter pit" em maçãs 'Fuji' e 'Catarina'. Os frutos foram colhidos, armazenados por 120 dias a 1ºC, com 90–95% de umidade relativa e, em seguida, divididos em lotes com ou sem sintoma de "bitter pit". Maçãs 'Catarina' apresentaram maior incidência e severidade de "bitter pit", em comparação a 'Fuji'. Em ambas as cultivares, os frutos com "bitter pit" apresentaram maior produção de etileno, respiração e acidez titulável, e menor pH, firmeza de polpa, textura da casca e da polpa e percentagem de cor vermelha na casca. Os frutos com "bitter pit" também apresentaram menores teores de Ca e maiores valores das relações K/Ca, N/Ca, (K+Mg)/Ca e (K+Mg+N)/Ca nos tecidos da casca e da polpa da região pistilar. A análise canônica discriminante indica que os atributos mais adequados para discriminar frutos com e sem "bitter pit" são força para penetração na polpa e relação K/Ca na polpa, em maçãs 'Fuji', e acidez titulável e relação K/Ca na casca, em maçãs 'Catarina'.

The objective of this work was to identify the physiological, physicochemical, and mineral attributes associated with the occurrence of bitter pit in 'Fuji' and 'Catarina' apples. Fruit were harvested, stored in air at 1ºC and 90–95% relative humidity for 120 days, and, then, divided into lots with or without bitter pit symptoms. 'Catarina' apples had higher incidence and severity of bitter pit, in comparison to 'Fuji'. In both cultivars, fruit with bitter pit had higher ethylene production, respiration, and titratable acidity, and lower pH, flesh firmness, skin and pulp textures, and percentage of red skin area. Fruit with bitter pit also had lower Ca content and higher values of K/Ca, N/Ca, (K+Mg)/Ca, and (K+Mg +N)/Ca ratios in the skin and flesh tissues of the blossom-end. Canonical discriminant analysis indicates that the best attributes to discriminate between fruit with or without bitter pit are force to penetrate the flesh and K/Ca ratio in the pulp, in 'Fuji' apples, and titratable acidity and K/Caratio in theskin, in 'Catarina' apples.