Acceso usuarios
In this study, changes in carbohydrate composition were investigated at the end of the biological cycle of two important table olive cultivars �Meski� and �Picholine� grown in Tunisia under different irrigation regimes. A control treatment [100% crop evapotranspiration (ETc)] and a stress treatment (50% ETc) were considered. At the end of August, leaf water potential was measured and sugar compounds were determined in mature leaves and in the wood of fruit-bearing branches by gas chromatography. The leaf water potential increased with the stress treatment in both cultivars, but the increase was more pronounced with �Picholine� than with �Meski�. Glucose, fructose, mannitol, sucrose, galactose and inositol were the main sugars found in the leaves and wood of olive trees. Glucose, fructose and mannitol accounted for 90% of the total soluble carbohydrate fraction. The fraction and amount of these sugars changed between cultivars and with irrigation treatment. In the control treatment, the leaves of Meski showed a high level of glucose (48%), fructose (19%) and mannitol (25%), while the leaves of Picholine showed amounts of 57, 15 and 17%, respectively. The restriction of irrigation water (50% ETc) induces an accumulation of glucose in the leaves and wood of �Meski� and an accumulation of mannitol and glucose in the wood of �Picholine�, while the leaves showed only an increase in mannitol.
