UNIQUE METHOD OF ESTABLISHING SOLAR RADIATION SATURATION LEVELS FOR GREENHOUSE CUCUMBER PRODUCTION

Hydroponically grown cucumbers, Cucumis sativus L. ‘Figaro F1.’, were studied in Ohio.
Two crops were grown; one in fall of 1994 and on in spring of 1995; in two compartments.
One of the two compartments was shaded with 33%-shade (nominal) black cloth.
Total plant dry weight samples were collected two times in each season while harvested fruit, plant height, leaf number, and leaf areas were collected on a weekly basis for 15 successive weeks.
Total solar radiation at the plant level was integrated and recorded every 10 minutes.
Results showed that solar radiation and daily/weekly dry weight gains were uncorrelated (R²=0.03) and it was later assumed the plants were saturating at some much lower radiation level than anticipated.
After constructing a series of potential optimum values for the mean hourly total solar radiation, the highest correlation coefficients were found for radiation levels below 100 W•m-2 for both fall and spring crops.

V International Symposium on Artificial Lighting in Horticulture

M.A. Medany, T.H. Short, A.F. Abou-Hadid

Cucumis sativus, PAR saturation, photosynthesis optimization, cucumber growth model, greenhouse lighting

https://doi.org/10.17660/ActaHortic.2006.711.13