Mobilizable carbon reserves in young peach trees as evidenced by trunk girdling experiments

Abstract

The seasonal patterns in concentrations of both soluble (NSC-S) and insoluble (NSC-I) non-structural carbohydrates, in 3-year-old peach trees (Prunus persica L. Batsch) grown in sand culture are described. The ability of trees to mobilize their carbohydrate reserves in response to scion-trunk girdling, which prevents photosynthate transport toward the roots, was tested at four phenological stages. Girdling induces a NSC-I depletion in roots and rootstock-trunk bark and a NSC-I accumulation in leaves and shoots. On the contrary, the NSC-S concentrations of the organs located both above and below girdling were not significantly affected by the treatment. Consequently, when phloem transport breaks down, trees, whatever their growing stage, mobilize carbohydrate reserves below the girdle to maintain the soluble sugar contents at the same level as in control trees.

Girdling, non-structural carbohydrates, Prunus persica L., carbon reserves, seasonal patterns