ISHS Acta Horticulturae 449: II International Symposium on Irrigation of Horticultural Crops
EFFECT OF NITROGEN CONCENTRATION ON GROWTH, WATER, AND NUTRIENT UPTAKE OF LETTUCE PLANTS IN SOLUTION CULTURE |
| Authors: | C.D. Economakis, R. Koleilat |
| Keywords: | Lettuce, NFT, nutrient solution, tissue nitrate content |
| Abstract:
Lettuce plants cv. "Ravel" were grown under unheated glasshouse conditions in nutrient solution culture (NFT), using different solution NO3-N concentrations of 50, 100, and 150 ppm. The objective of the experiment was to determine the minimum nitrogen concentration in the nutrient solution resulting in a minimum shoot nitrate content without affecting significantly shoot fresh weight. Fresh shoot weight (438.2 – 425.3 – 423.6 g) and shoot dry weight (28.3 – 27.6 – 26.8 g) were not affected significantly by the nitrogen concentration. Root dry weight decreased with increasing N concentration reaching its maximum with the minimum N concentration (2.7–2.2–2.0 g), while shoot nitrate content (mg NO3-N/kg fresh shoot weight) was affected mainly by the time of harvest, being always less than 1000mg/kg. Cumulative water uptake during the growing period was slightly higher for the low (50ppm) N treatment (8.4 – 7.8 – 7.2 l/plant), while the uptake of N, P, and K increased with increasing N concentration in the nutrient solution. | |
Download Adobe Acrobat Reader (free software to read PDF files) | |
