Photosynthetic, photoprotective and antioxidant responses during high temperature stress were determined in leaves of evergreen holm oak (Quercus ilex L.), the main species in Mediterranean forests, during resprouting under elevated CO(2) (750 μl·l(-1) ). Leaf chemicals, chloroplast pigments and non-enzymatic antioxidants were quantified in a single measurement using NIRS (near-infrared spectroscopy), a rapid and suitable method for ecophysiological purposes.
View Article and Find Full Text PDFIn order to further study a previously observed relationship between polyamine (PA) content and changes in irradiation, we examined the level of free and bound PAs, the activity of transglutaminase (TGase, EC 2.3.2.
View Article and Find Full Text PDFTobacco (Nicotiana tabacum L. cv. Petit Havana) callus cultures were exposed to UV-C high dose pulse-treatment (254 nm, 50 kJ m(-2), 1 h-treatment).
View Article and Find Full Text PDFPlant Cell Rep
December 1997
Four callus lines from immature embryos of a self-crossed maize (Zea mays L.) hybrid cultivar were selected for "high" (two lines) and "low" (two lines) polyamine (PA) levels. Each selected line was exposed to culture media containing no (control) or 1% (0.
View Article and Find Full Text PDFThe inhibition of K(+) uptake through the plasma membrane resulting from injury caused by cutting, or from application of polyamines (PAs), has been investigated in root segments of maize (Zea mays L.) and pea (Pisum sativum L.).
View Article and Find Full Text PDFThe action of exogenous polyamines (putrescine, spermidine, and spermine) on ;washing' and fusicoccin-stimulated K(+) uptake and H(+) extrusion through the plasmamembrane in maize (Zea mays L., hybrid line Plenus S 516) root apical segments was studied. The results showed that polyamines inhibit the washing-stimulated K(+) influx and H(+) extrusion without interfering with K(+) uptake and H(+) extrusion stimulated by fusicoccin.
View Article and Find Full Text PDFActive K(+) influx was studied in apical segments from maize (Zea mays L., hybrid lines XL 342) and pea (Pisum sativum L. var Laxton superbo) seedlings pretreated with the herbicide chlorsulfuron (2-chloro-N-[(4-methoxy-6-methyl-1,3,5-triazin-2-yl) aminocarbonyl]benzenesulfonamide).
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