Rice (Oryza sativa L.) plants were grown over a 30-d period in nutricnt soiution containing concentrations of Cu varying from 0.002 to 6.25 g iit^, and ihen oxygen toxicity was investigated in the chloroplasts. The Cu concentration in the shoots increased with increasing levels of this metal in the nutrient soiution, whereas the Fe concentration decreased after the 0.05 g m'^ Cu treatment and the Zn concentration did not show any clear tiend. Catalase, glutathione reductase and Cu,Zn-superoxide dismutase activities decreased with increasing Cu levels. On a fresh mass basis, ethylene production decreased after the 0.05 g Cu treatment, whereas, on a chlorophyll (Chl) basis, it increased until the 1.25 g m‘^ Cu iTeatment. The chloroplast lipid peroxidation increased (on a Chl and lipid basis) between the 0.01 and the 1.25 g m"^ Cu treatment. On a fresh mass basis the concentration of chloroplastic digalactosyldiacylglycerol, monogalactosyldiacylglycerol, phospha- tidylcholine, phosphatidylglycerol and phosphatidylinositol decreased, whereas, on a Chl basis, the concentration of the first two lipids sharply decreased after the 0.01 gm‘3 Cu treatment. Additionally, only a slight decrease was foiind in the concentration of phosphatidylglycerol with increasing Cu concentrations. Measurements of the linolenate hydroperoxide concentration in these acyl lipids showed an increase after the 0.01 g m'^ Cu treatment for the fnst two lipids as weil as an increase with increasing Cu levels for phosphatidylglycerol.
During the vegetation period from June to October 1990 the growth, photosynthetic C02-fixation, pigment content and chlorophyll (Chl) fluorescence characteristics were compared in the needles of 5-year-old spruce dones Picea abies (L.) Karst., cultivated for two years on the soil and the sand, with or without addition of minerál fertilizers. Minerál deflciency in the spruce dones grown on the sand instead of a humus containing soil resulted in somewhat reduced lengthwise growth of shoots and needles, lower level of Chl and carotenoids (Car), as well as lower net photosynthetic rates (F^) per needle area unit and in generál also lower stomata conductance (gH2o) values. In contrast, the variable Chl fluorescence measured via the Chl fluorescence decrease ratio (Rfj = fd/fs) was only little affected, indicating an intemal íunctional photosynthetic apparatus even under minerál deflciency with a lower Chl content. In fact, Fj,} expressed on Chl basis was even signiflcantly higher in the newly developed 1990 needles of the sand cultures than in the soil ones. Application of a forestry fertilizer with basic minerals (K, Ca, Mg and some N) to the sand cultures increased growth of shoots and needles, levels of Chl and Čar, F^ and stomata conductance, and decreased the Chl fluorescence ratio F690/F735 and lability of the photosynthetic apparatus, as also seen in increased values of the ratio Chl/Car (a+b/x+c). The hasič minerál elements are thus necessaiy for the photosynthetic apparatus development, as well as stability of its pigment content and physiological function.