Cytology of oil–body cells in Ricciocarpus natans

Abstract

Oil–body cells in the liverwort Ricciocarpus natans are present as idioblasts and contain a single oil–body each. The limiting membrane of the oil–body has a tripartite dark–light–dark configuration. The layer facing the oil–body is thickest. Lipophilic globules are embedded in a matrix, which reacted positively for proteins, polysaccharides and lipids. The globules, which initially are minute, can coalesce to larger units, ultimately forming a single one. A peripheral layer was recognized by its different stainability. This layer was sometimes separated from the rest of the globule. Some seasonal variability was observed in the nature of the matrix and the amount of lipophilic material.The origin of the oil–body from the central vacuole was traced from the meristematic zone. The resemblance between the oil–body membrane and the tonoplast is in accordance with this origin. Smooth endoplasmic reticulum is extensively developed and seems to contribute material to the developing oil–body.