Intrusive growth of initials does not affect cambial circumference in Robinia pseudoacacia.

This study aimed to test the hypothesis whether intrusive growth of initial cells is related to the increase in circumference of Robinia pseudoacacia vascular cambium-both qualitatively and quantitatively. The mode of intrusive growth of cambial initial cells was also studied. Samples collected from tree trunks were examined using series of semi-thin transverse sections.

What do we know about growth of vessel elements of secondary xylem in woody plants?

Despite extensive knowledge about vessel element growth and the determination of the axial course of vessels, these processes are still not fully understood. They are usually explained as resulting primarily from hormonal regulation in stems. This review focuses on an increasingly discussed aspect - mechanical conditions in the vascular cambium.

How Do Trees Grow in Girth? Controversy on the Role of Cellular Events in the Vascular Cambium.

Radial growth has long been a subject of interest in tree biology research. Recent studies have brought a significant change in the understanding of some basic processes characteristic to the vascular cambium, a meristem that produces secondary vascular tissues (phloem and xylem) in woody plants. A new hypothesis regarding the mechanism of intrusive growth of the cambial initials, which has been ratified by studies of the arrangement of cambial cells, negates the influence of this apical cell growth on the expansion of the cambial circumference.

Readjustments of cambial initials in Wisteria floribunda (Willd.) DC. for development of storeyed structure.

•  This study has elucidated the mechanism of development of the storeyed cambial structure of Wisteria floribunda, a species characterised by very quick and early establishment of storeyed structure from a nonstoreyed procambium in close vicinity of the pith. •  Rearrangement of the cambial cells was studied in serial tangential longitudinal sections of axial wood parenchyma. •  The mechanism of cell rearrangement was found to involve not only the occurrence of anticlinal cell divisions, but also a concomitant intrusive growth of the ends of cambial cells of one cell packet along the tangential walls of cells of the neighbouring packet.