Mortensen Leiv M
Agricultural University of Norway, Department of Floriculture and Greenhouse Crops, P.O. Box 13, N-1432 Aas-NLH, Norway.
New Phytol. 1986 Dec;104(4):653-660. doi: 10.1111/j.1469-8137.1986.tb00666.x.
Seedlings of Lycopersicon esculentum (tomato) were subjected to CO -enriched air (1000 μl 1 ) containing 1.5 μ l nitrogen oxides (NO ) for 25 d at four photon flux densities (30, 95, 175 and 250 μmol m s PAR). CO enrichment without NO significantly increased the dry weights (47 to 93 %) at all light levels. Addition of NO strongly reduced the mean dry weight at the lowest light level even below that of the unenriched control. At the two highest light levels, NO reduced the dry weight, but much less than at the lowest level. NO caused severe leaf injury at the lowest light level, but this effect disappeared with increased photon flux density. A system was constructed for measurement of the net CO., exchange rate (CER) for single plants. Short-term measurements showed significant reductions of CER when the NO concentration was increased from 0 to 9μl 1 at 550μmol m s but almost no effect at 140 to 200 μmol m s . NO caused similar percentage reductions of CER at 335 and 1000 μl CO . The absorption of NO was not significantly affected by increasing the photon flux density from 150 to 550μmol m- s .
