Showing papers by "Anita Solar published in 2004"

Flavonols of leaves in relation to apple scab resistance

Abstract: Phenolic compounds of three scab-resistant apple cultivars ‘Topaz’, ‘Goldstar’ and ‘Gold Rush’ and two susceptible ones ‘Golden Delicious Weinsberg’ and ‘Golden Delicious Clone B’ were studied. The leaves were sampled four times in the period from 12 June to 10 September 2001. Flavonols rutin, quercitrin and ‘phenol 173’ (phenol with retention time 173,38 min) were analyzed using the Hplc system. Between the resistant and susceptible cultivars, statistically significant differences were established in the relative content of ‘phenol 173’, which was higher in the resistant cultivars during the growing season. It appears that the content is not affected either by different environmental conditions or by different stressors, but only by the genotype. Differences in the content of rutin and quercitrin were not significant. During the growth period, the content of phenolic compounds changed and was related to the physiological stage of the tissue and cultivar used.

Changes in Polyphenols in Leafy Cuttings During the Root Initiation Phase Regarding Various Cutting Types at Castanea

Abstract: There are some disadvantages of the present propagation methods (grafting, micropropagation) of the genus Castanea (Fagaceae). The leafy cutting propagation method, which seems to be the best alternative, is to be optimised to achieve successful propagation results. The polyphenol analyses during the root initiation phase and the root growing phase (first month after being put in the substrate) were carried out to clarify some problems during the rooting process (bad rooting, strong callus formation). Several polyphenol substances which were identified in the cuttings, can negatively affect the rooting process. The tannic and gallic acid were identified in cutting bases and stems. In cutting leaves tannic acid, gallic acid, ellagic acid, quercetin-3-d-galactoside (hyperoside, Q3DG) and quercetin-3-rhamnoside (quercitrin, Q3R) were identified. The contents of all those substances increased over the period from the time the cuttings were put in the substrate till the fifth day in the substrate. The increase of tannic acid and quercetin-3-rhamnoside after five days determined in cutting leaves was significant.