RESUMO: A Viola cornuta é uma planta facultativa de dias longos que floresce de outubro até março, na Turquia. Durante os meses de inverno, os baixos níveis de luz podem limitar o crescimento e desenvolvimento da planta. Diodos emissores de luz (LEDs) podem fornecer iluminação suplementar em estufas produzindo a mesma intensidade de luz que uma lâmpada incandescente convencional, com menor consumo de energia. As tecnologias de emissão de luz através de diodos permitem sistemas acessíveis e eficientes que podem ser instalados em estufas e túneis de plástico no campo. Neste experimento avaliou-se os efeitos da suplementação por LED vermelho-alaranjado no crescimento e desenvolvimento de Viola cornuta, cv. Blue Blotch, cultivada em túneis plásticos. A energia necessária para o funcionamento dos LEDs foi fornecida através de um sistema de painéis solares com o objetivo de chamar a atenção para a fonte de energia solar não poluente. Cinco horas de iluminação suplementar por LED foram aplicadas após o entardecer, de novembro a fevereiro. Parâmetros de crescimento e desenvolvimento do amor perfeito foram comparados com o não fornecimento de luz às plantas testemunha. Iluminação suplementar por LED aumentou significativamente o peso da biomassa da planta, número de flores e número de folhas à taxa de 52, 72 e 47%, respectivamente. Além disso, a iluminação LED aumento a taxa de crescimento das plantas (0,109 e 0,306 g de peso fresco), em comparação com o controle sem luz. Iluminação por LED no entanto, não teve efeito sobre o comprimento do caule, número de ramos e o diâmetro das flores. Assim, este estudo indicou que o amor perfeito sofre limitação no seu desenvolvimento pela menor iluminação durante os meses de inverno e, iluminação suplementar por LED pode aumentar significativamente o crescimento e o seu desenvolvimento.

ABSTRACT: Pansy (Viola cornuta) is a facultative long-day plant that flowers from October until March in Turkey. During the winter months, low light levels can limit plant growth and development. Light emitting diodes (LEDs) can provide supplemental lighting in greenhouses which produce same light intensity with less energy than conventional incandescent lighting. Light emitting diode technologies have enabled affordable and efficient light systems to be installed in greenhouses and plastic tunnels in the field. In this experiment we evaluated the effects of supplemental red-orange LED lightening on the growth and development of pansy cv. Blue Blotch grown in plastic tunnels. The energy, which LEDs are to consume, was provided through a solar panel system with the aim of drawing attention to the cleanliness of solar energy source. Five hours of supplement LED lighting was applied after dusk starting from November to February. Pansy growth and development parameters were compared with non-light supplied control plants. Supplemental LED lighting significantly increased plant biomass weight, flower number and leaves number at the rate of 52%, 72%, and 47%, respectively. Moreover, LED lighting increased plant growth rate (0.109 and 0.306 g of fresh weight), compared with the no light control. LED lighting, however, had no effect on length of stems, number of branches and the diameter of flowers. Thus, this study indicated that pansies are light limited during the winter months and supplemental LED lighting can significantly increase pansy growth and development.

Cauliflower heads, which were precooled using four different methods including vacuum, forced-air, and high and low flow hydro precooling, were stored under controlled atmosphere and room conditions. Controlled atmosphere conditions (CA) were as follows: 1°C temperature, 90 ± 5% relative humidity, and 0:21 [(%CO2:%O2) – (0:21) control] atmosphere composition. Room conditions (RC) were: 22±1°C temperature and 55-60% humidity. Various quality parameters of the cauliflower heads were assessed during storage (days 0, 7, 14, 21, 28, and 35) under controlled atmosphere and room conditions (days 0, 5, and 10). During storage, weight loss, deterioration rate, overall sensory quality score, hardness, and colour (L, a, b, C and α) were evaluated. In the present study, the strength and quality parameters of cauliflower under CA and RC conditions were obtained. Vacuum precooling was found to be most suitable method before cauliflower was submitted to cold storage and sent to market. Furthermore, the storage of cauliflower without precooling resulted in a significant decrease in quality parameters.

The aim of the present study was to precool cauliflower using forced-air, vacuum and high and low flow hydro cooling methods. The weight of the precooled cauliflower heads (5000±5 g) was measured before they were placed in standard plastic crates. Cauliflower heads, whose initial temperature was 23.5 ± 0.5 ºC, were cooled until the temperature reached at 1 ºC. During the precooling process, time-dependent temperature and energy consumption were measured, and during vacuum precooling, the decreasing pressure values were recorded, and a curve of time-dependent pressure decrease (vacuum) was built. The most suitable cooling method to precool cauliflower in terms of cooling time and energy consumption was vacuum, followed by the high and low flow hydro and forced-air precooling methods, respectively. The highest weight loss was observed in the vacuum precooling method, followed by the forced-air method. However, there was an increase in the weight of the cauliflower heads in the high and low flow hydro precooling method. The best colour and hardness values were found in the vacuum precooling method. Among all methods tested, the most suitable method to precool cauliflower in terms of cooling and quality parameters was the vacuum precooling method.