Suchergebnisse

Summary. — 10-3 M gibberellic acid induces a significant increase of respiratory exchanges in tissue slices of tubers of Solanum tuberosum. The intervention of this hormone in the respiratory cycles is analysed both with the action of effectors and with the measure of specific activity of enzymes of this metabolic pathway. Enolase, hexokinase, aldolase and triose-phosphate isomerase enhance their activity. On the contrary there is few rise of peroxidase activity.

Influence of gibberellic acid on the oxygen uptake of fragmented tissues of tubers of S. tuberosum as a function of the age of these storage organs. Application of gibberellic acid at various concentrations has been repeated regularly to potato discs from the central part of the tubers in the course of the months following two consecutive harvests. Definite variations have been observed in the possibility to modify the oxygen uptake of these storage organs conserved in controlled conditions after harvest, such variations being related to the sprouting stage of the tubers.