Una Struttura Comparabile Con I Lomasomi Nelle Cellule Austoriali di Cuscuta Pentagona Engelm

Abstract

A structure comparable with the lomasomes in baustorial cells of « Cuscuta pentagona » Engelm. — Electron microscopic observations of haustorial cells in « Cuscuta pentagona » revealed to the A. the presence of some vesicular structures, outside the plasma membrane, comparable to the lomasomes of Moore and McAlear. The vesicles usually group in a bag of the plasma membrane and show an envelope consisting of unit membrane; their shape and size are variable and some of them are not well distinct while some others show ribosome-like bodies inside .In the examined cells the plasma membrane shows prominences which are in connection with the vesicle membrane, so that the A. thinks it possible the derivation of the vesicles from the peripherical cytoplasm. The function of these structures is not yet explained; they are only found in non photosyntetic cells, such as some Mycophyta, dark grown « Avena » coleoptiles and dodder's haustorial cells. The previously ultrastructural researchs on dodder have not pointed out lomasomes, which seem to be exclusive of the haustoria, so that it is possible to suppose a connection between the lomasome function and that of the haustoria.