The significance of cell wall invertase (cwINV) for plant defense was investigated by comparing wild-type tobacco (Nicotiana tabacum) Samsun NN (SNN) with plants with RNA interference (RNAi)-mediated repression of cwINV (SNNcwINV). In source leaves of SNNcwINV, the activity of cwINV was repressed by about 90%. Sucrose export and apoplastic carbohydrate levels were significantly reduced, while p...

Sugar beets (Beta vulgaris L.) infected with the Beet Yellows Virus exhibit lower rates of net photosynthesis at light saturation than do healthy plants. These Pn reductions were correlated with increases in leaf resistance to water vapor loss. Theoretical analyses demonstrated that, although the leaf resistance to water vapor loss increases could account for a major part of the net photosynthe...

tobacco is a salt-sensitive glycophyte crop species. in this work effect of silicone (si) supplementation (1 mm as na2sio3) was studied in nicotiana rustica l. cv. basmas grown hydroponically in growth chamber under control, low (25 mm) and high (75 mm) nacl concentration for two weeks. dry matter production of leaves was depressed by salinity level as low as 25 mm and higher salt concentration...

Asian grapevine rust (Phakopsora euvitis) is a serious disease, which causes severe leaf necrosis and early plant defoliation. These symptoms are unusual for a strict biotrophic pathogen. This work was performed to quantify the effects of P. euvitis on photosynthesis, carbohydrates, and biomass accumulation of grapevine. The reduction in photosynthetic efficiency of the green leaf tissue surrou...

Tissue osmotic potential and solute constituents were evaluated in leaves and roots of well-watered and water-stressed Prunus avium L. × pseudocerasus Lindl. ‘Colt’ and Prunus cerasus L. ‘Meteor’. Osmotic potential at full turgor decreased in response to water stress for leaves and roots of both cultivars. For ‘Colt’, a cultivar with an indeterminate growth habit, decreased by 0.56 MPa and 0.38...

From the literature and from numerous experiments made at the Scientific Institute of Fertilizers, it is well known that high amounts of chlorides lower the percentage of starch in potato tubers. While the depressing influence of fertilizers containing chlorine on the total yield of potatoes is not always manifested, the decrease of the starch content in the tubers may be considered a constant ...

In this study we have demonstrated the variations of carbohydrates and phenolic compounds present in the leaves and stems of ‘Kinnow’ mandarin (Citrus reticulata Blanco) trees in alternate bearing cycle and the possible involvement of these compounds to flower bud formation process. The amounts of these compounds were determined in the leaves and stems of “on” and “off” trees  monthly  from Nov...

Two soybean (Glycine max L. Merrill) cultivars, Shin-Tanbakuro and Midori, were grown under mild water stress conditions for 11 days at the vegetative growth stage in order to examine the effect of drought stress on plant biomass production, photosynthetic gas exchange, chlorophyll fluorescence and photoassimilate translocation along with changes in carbohydrates and nitrogen. Relative growth r...

Influence of different light regimes (plants grown in shade and in the sun) on respiration, activity of alternative respiratory pathway and carbohydrates content in mature leaves of Ajuga reptans L. was investigated. All experiments were carried out under natural conditions. Sun plants had higher respiration, activity of the alternative pathway and carbohydrates content compared to the shade pl...