Effects of 6-Benzylaminopurine and Potassium Chloride on the Greening of Detached Cucumber Cotyledons

Autor: Jean Roussaux, N. Farineau, C. Le Pabic
Rok vydání: 1983
Předmět:
Zdroj: Zeitschrift für Pflanzenphysiologie. 111:261-272
ISSN: 0044-328X
Popis: Summary Etiolated cotyledons of cucumber (Cucumis sativus L.) were excised and maintained on water or transfered at various times to 6-benzylaminopurine (BA, 10-6 g· ml-1) or KCl (10-2M) or a combination of BA+KCl at the same concentrations. The experiment was carried out in continuous light for a total period of 10 days. BA and mainly KCl stimulated chlorophyll synthesis during the first days, after which the sensitivity of cotyledons to these compounds decreased with age. A combination of BA+KCl had a greater effect; moreover, the sensitivity of cotyledons persisted even after 7 days of incubation. The synthesis of polar lipids was also enhanced by these treatments at the beginning of incubation, phospholipid synthesis being particularly stimulated by BA and glycolipid synthesis by KCl. The combination of BA+KCl was always more active. The increase in C 18 : 3 content observed in the control was greater in cotyledons incubated on BA and on BA+KCl. Parallel changes in plastid ultrastructure were also observed and the increase in thylakoids and granal stacks development was maximal during the first days of incubation with BA+KCl. It is concluded that K+ is the first limiting factor during the greening process of excised cotyledons. Cytokinin would act more specifically on the cytoplasmic compartment whereas KCl would be active on both the cytoplasmic and chloroplastic compartments.
Databáze: OpenAIRE