Compartmented cells in the mesophyll of Araucaria angustifolia (Araucariaceae)

Abstract

The compartmented cells of the immature and mature leaves of young and adult plants of Araucaria angustifolia (Bert.) O. Ktze. are characterised by the presence of pectinous partitions in the cell lumen, forming a system of compartments. The function of these cells is possibly related to water storage and translocation. The morphology of compartmented cells differs from that of immature and mature leaves: at the time of maturity the compartment system or secretion is more defined. These cells undergo the programmed cell death (PCD) process, because they are enucleated in adult plants. The compartmented cells' cytology and pectic composition are similar to the mucilage cells of Lauraceae and Cactaceae.