The Influence of Greenhouses on Internal Climate With Special Reference to Mediterranean Regions

Hanan, Joe J.

doi:10.17660/actahortic.1991.287.1

Cited by 7 publications

(7 citation statements)

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“…To prevent a shoot-tip temperature depression at night, the energy lost from transpiration must be balanced with the energy gained from convection and absorbed LWR. During winter in temperate climates, VPD at night can increase considerably because of infiltration of outside air containing little water vapor and the subsequent heating of this air (Hanan, 1990). These results indicate that during greenhouse production of New Guinea impatiens, especially during winter, injecting water vapor into the air to decrease VPD would reduce transpiration and increase plant temperature.…”

Section: Resultsmentioning

confidence: 94%

Greenhouse Energy Curtains Influence Shoot-tip Temperature of New Guinea Impatiens

Blanchard

Runkle

Both³

et al. 2012

horts

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Many greenhouse growers have installed retractable energy curtains to reduce energy losses and heating costs. We performed experiments to quantify the effect of retractable nighttime curtains on plant shoot-tip temperature of New Guinea impatiens (Impatiens hawkeri Bull.) grown in glass-glazed greenhouses during winter. Plants were grown in separate greenhouses under different curtain materials and the following measurements were collected: plant shoot tip, aerial wet and dry bulb, and cover (glazing and superstructure or curtain) temperature; net canopy radiation (250 to 60,000 nm); transmitted shortwave radiation (SWR; 300 to 3,000 nm); and air velocity. At night, plants under an extended curtain had a higher (by 0.5 to 2.3 °C) shoot-tip temperature and the net longwave radiation (LWRnet; 3,000 to 100,000 nm) was 70% to 125% greater than plants without a curtain. Shoot-tip temperature was 0.2 to 0.6 °C lower under a shading curtain with open-weave construction (high air permeability) compared with closed-weave constructed curtains (e.g., blackout). As cover temperature decreased from 21 to 12 °C, measured shoot-tip temperature and LWRnet decreased by a mean of 3.0 °C and 39.1 W·m−2, respectively. Under a vapor pressure deficit (VPD) of 0.4 to 0.9 kPa, plant shoot-tip temperature was a mean of 1.0 °C closer to dry-bulb temperature compared with plants under a VPD of 1.4 to 1.8 kPa as a result of decreased transpiration. During the day, shoot-tip temperature was 1.2 °C lower than dry-bulb temperature when transmitted SWR was less than 100 W·m−2 and on average 1.6 °C higher than the dry-bulb temperature when SWR was more than 100 W·m−2. Therefore, in addition to reducing greenhouse heating costs, a curtain extended at night over a crop of New Guinea impatiens could increase plant shoot-tip temperature and accelerate development.

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Section: Resultsmentioning

confidence: 94%

Greenhouse Energy Curtains Influence Shoot-tip Temperature of New Guinea Impatiens

Blanchard

Runkle

Both³

et al. 2012

horts

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“…These results were confirmed with that indicated by (Mortensen and Stromme, 1987) who mentioned that light penetrates transparent glass or plastic, and the spectral distribution of light will differ with the colour of the transparent material Plastic cover reduced total light intensity and different-density shade clothes. Within certain range, the one percent reduction in radiation on the crop canopy is worth one percent reduction in yield (Hanan, 1990).…”

Section: Light Intensitymentioning

confidence: 99%

Effect of Colour of Plastic Net House Cover and Soil Mulch on Growth and Productivity of Cucumber

Saleh

Abou-Shleel

2012

Egyptian Journal of Agricultural Research

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The current study was conducted at El-Nubaria area, , El-Behera Governorate, Egypt, during autumn 2009 and 2010 seasons in order to investigate the growth and productivity of cucumber (Cucumis sativus L. c.v. Hesham F 1 hybrid) under different plastic net cover colours and different plastic mulch colours. Seeds were sown on first of September and seedlings were transplanted in 15 th of September 2009 & 2010, respectively.Three plastic net colours were applied, namely, red, blue and white whereas the white was used as a control. In addition two-soil plastic mulch colours (black and transparent) were applied for each house, besides bare soil (without mulching) as control.The best results were obtained under the white plastic net (control), which had the highest total yield as well as light intensity, followed by the red, and finally blue plastic net colour. The highest length of plant, total leaf area and number of leaves as well as air temperature and humidity, soil temperature, were found in the red plastic net colour, followed by control and finally with the blue plastic net cover colour. Results also indicated that the white plastic mulch was recorded the highest values of all measured parameters followed by black and without mulching. Interaction between plastic net colours and plastic mulch showed that, the white net with transparent plastic mulch treatment had the highest plant, yield and soil temperature, but the treatment of transparent plastic mulch under red net colour had the highest number of leaves, leaf area and stem diameter.

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“…HANAN (1990) comenta que a aplicação de CO 2 diretamente na planta, procedimentos usados pelos americanos e holandeses, é o sistema de distribuição de gás mais apropriado. Porém, GOMES et al (2005), utilizando aplicação de CO 2 via água de irrigação, em produção de alface em cultivo no solo, alcançaram aumento de produtividade de aproximadamente 20,5%.…”

Section: Introductionunclassified

Produção de alface hidropônica em três ambientes de cultivo

Costa

Leal

2009

Eng. Agríc.

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Propôs-se avaliar a produção hidropônica de alface-crespa, variedade "Vera", em bancadas inclinadas com canais de 100 mm, utilizando a técnica de filme de solução nutritiva, em resposta à aplicação de dióxido de carbono e ao resfriamento evaporativo. Realizaram-se cinco ciclos de cultivo nos períodos de 20-3 a 17-4-2000 (C1); 25-5 a 29-6-2000 (C2); 13-7 a 21-8-2000 (C3); 27-8 a 2-10-2000 (C4) e 12-12-2000 a 10-1-2001 (C5). Avaliaram-se três casas de vegetação, sendo casa de vegetação sem sistema de resfriamento evaporativo do ar e sem injeção aérea de CO2 (A1); casa de vegetação com injeção aérea de CO2 e sem sistema de resfriamento evaporativo do ar (A2), e casa de vegetação com injeção aérea de CO2 e com sistema de resfriamento evaporativo do ar do tipo meio poroso-exaustor (A3). Avaliaram-se as massas frescas e secas em gramas, o número de folhas e a área foliar em mm². Utilizou-se do delineamento inteiramente casualizado, em que, no ciclo C1, utilizaram-se 48 repetições por ambiente; para os ciclos C2, C3 e C5, foram 64 repetições, e para o ciclo C4, foram 24 repetições. O ambiente climatizado com incremento de dióxido de carbono promoveu melhor desenvolvimento das plantas, com maior número de folhas comercializáveis. Em ambientes não climatizados, o incremento de CO2 não resultou em aumento de produtividade da alface para a maioria dos ciclos. Em épocas de temperaturas mais elevadas, obtiveram-se plantas maiores, com maior número de folhas.

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The Influence of Greenhouses on Internal Climate With Special Reference to Mediterranean Regions

Cited by 7 publications

References 0 publications

Greenhouse Energy Curtains Influence Shoot-tip Temperature of New Guinea Impatiens

Greenhouse Energy Curtains Influence Shoot-tip Temperature of New Guinea Impatiens

Effect of Colour of Plastic Net House Cover and Soil Mulch on Growth and Productivity of Cucumber

Produção de alface hidropônica em três ambientes de cultivo

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