Correlation of intrusive growth of cambial initials to rearrangement of rays in the vascular cambium

It is well documented that apical elongation of fusiform cambial initials through extension of their longitudinal edges, and their intrusion between tangential walls of the neighbouring initials and their closest derivatives cause rearrangement of fusiform cells, without increasing the cambial circumference. However, the concurrent rearrangement of rays is not fully understood. This study deals with Pinus sylvestris L., Tilia cordata Mill. and Hippophaë rhamnoides L., possessing a nonstoreyed, storeyed and double-storeyed type of cambium, respectively, and shows that the mechanism for rearrangement of ray initials is similar to the one proposed for fusiform initials, and includes multiplication of ray initials by anticlinal divisions, intrusive growth of ray initials, elimination of ray initials caused by intrusive growth of neighbouring fusiform initials, and transformation of ray initials into fusiform initials. Intrusive growth of a ray initial does not necessarily lead to the formation of a new fusiform initial, as it is dependent on the extent of the intrusive growth taken place. The extent of rearrangement of cambial cells is determined by the intensity of events occurring among the fusiform as well as ray initials. Intrusive growth of these initials does not influence the size of the cambial circumference.

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Apical intrusive growth of cambial fusiform initials along the tangential walls of adjacent fusiform initials: evidence for a new concept

Australian Journal of Botany ◽

10.1071/bt05130 ◽

2006 ◽

Vol 54 (5) ◽

pp. 493 ◽

Cited By ~ 7

Author(s):

Joanna Jura ◽

Paweł Kojs ◽

Muhammad Iqbal ◽

Joanna Szymanowska-Pułka ◽

Wiesław Włoch

Keyword(s):

Cell Walls ◽

Tilia Cordata ◽

Intrusive Growth ◽

Radial Wall ◽

Cambial Cell ◽

Fusiform Initials ◽

Periclinal Walls ◽

Symplastic Growth ◽

Wisteria Floribunda ◽

Fusiform Initial

A new study of cambium of Pinus sylvestris L., Tilia cordata Mill. and Wisteria floribunda (Willd.) DC provides fresh clues on the cambial dynamics, rejecting the hitherto held concept that intrusive growth of the fusiform initial occurs between the radial walls of adjacent initials. It demonstrates that intrusion of the elongating initial in fact takes place along tangential walls of adjacent fusiform initials and their immediate derivatives. It also suggests a new mechanism for ‘elimination of initials’. Intrusive growth of the fusiform initial was found to begin with development of characteristic slants, representing a transitional stage of the process of transformation of periclinal walls of fusiform initial cells into radial walls, as observed in transverse sections of active cambium. The gradually progressing event comprised (a) appearance of either a triangular microspace limited by two periclinal walls of a fusiform initial and its derivative and one radial wall of another fusiform initial in the adjacent radial file, or a rhomboidal microspace enclosed by four periclinal walls of two laterally adjacent fusiform initials and their immediate derivatives, (b) intrusion of elongating tip of fusiform initial from neighbouring file into the microspace thus formed, (c) symplastic growth of the cambial cell walls in radial direction, (d) unequal periclinal divisions of fusiform initial cells while growing intrusively, and (e) unequal periclinal divisions of derivative cells not growing intrusively. Intrusive growth between periclinal walls affected rearrangement of the fusiform initials but did not add to the cambial circumference. The existing concepts of (a) intrusion of the fusiform initial between radial walls of neighbouring initials and (b) elimination of fusiform initials from cambial surface have been reassessed and redefined.

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Vertical migration of rays leads to the development of a double-storied phenotype in the cambium of Aesculus turbinata

Botany ◽

10.1139/b07-114 ◽

2008 ◽

Vol 86 (1) ◽

pp. 36-44 ◽

Cited By ~ 3

Author(s):

Elżbieta Myśkow ◽

Beata Zagórska-Marek

Keyword(s):

Vertical Migration ◽

Hippophae Rhamnoides ◽

Vascular Cambium ◽

Common Descent ◽

Hippophaë Rhamnoides ◽

Fusiform Initials ◽

Hippophae Rhamnoïdes L ◽

Ray Cell ◽

Ray Initials

In the vascular cambium of Aesculus turbinata (Blume) the double-storied structure develops slowly. Initially, the arrangement of primary rays is nonstoried. New secondary rays are initiated during cambial expansion. Rays grow by addition of new initials at both ray margins and then split by the intrusive elongation of adjacent fusiform cells. The repetitive splits give rise to groups of several rays of common descent. Initially, the secondary rays are also nonstoried. Later, they become organized into horizontal tiers. This results from the vertical migration of ray initials in the vascular cambium. Controlled polar additions and eliminations of ray-cell initials at the opposite margins of the ray continue until it reaches the appropriate position within the storey of fusiform initials. We postulate that there are at least two mechanisms for the formation and maintenance of ray tiers in cambium. They are unrelated to cell inclination changes, which as described earlier, are known to sometimes induce a double-storied phenotype. The first of these mechanisms, involves initiation of secondary rays exactly within the storeys of fusiform initials, as in Hippophaë rhamnoides L. The second mechanism, present in A. turbinata, is based on the dynamic, controlled migration of rays.

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THE REDUCTION OF FUSIFORM CAMBIAL CELLS IN CHAMAECYPARIS AND THUJA

Canadian Journal of Botany ◽

10.1139/b51-006 ◽

1951 ◽

Vol 29 (1) ◽

pp. 57-67 ◽

Cited By ~ 17

Author(s):

M. W. Bannan

Keyword(s):

Frequent Occurrence ◽

Daughter Cells ◽

Fusiform Initials ◽

Cambial Cells ◽

Fusiform Initial ◽

Ray Initials

The loss of fusiform initials from the cambium, which is of frequent occurrence in all parts of the tree, takes place in different ways. Some cambial cells seem gradually to fail and are shortly lost from the cambium by maturation into more or less imperfect xylem or phloem elements. The majority are transversely subdivided by one or a succession of anticlinal divisions which begin near the center of the fusiform initial and usually extend to the daughter cells. The resulting segments shorten through the following periclinal divisions, some disappearing during the process of shortening and others undergoing transformation to ray initials. Nearly all new rays in the secondary body originate in this manner.

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Desenvolvimento e mudanças celulares na estrutura dos raios xilemáticos de Rollinia emarginata Schlecht. (Annonaceae)

Ciência e Natura ◽

10.5902/2179460x25496 ◽

1988 ◽

Vol 10 (10) ◽

pp. 131

Author(s):

Paulo Cesar Botosso

Keyword(s):

Secondary Xylem ◽

Intrusive Growth ◽

Outermost Layer ◽

Cellular Changes ◽

Fusiform Initials ◽

Cellular Transformations ◽

Ray Initials

Through microscopical observations in serial tangential sctions from cambium to pith the development and the most significant cellular changes in the structure of rays of Rollinia emarginata Schlecht. (Annonaceae) were observed. The ray characteristics of the outermost layer of secondary xylem are described and the major changes in the ray structure in different stages of secondary develooment are considered. The cellular changes observed are extremely variable, occurring isolated or in complex combinations. The most significant cellular changes observed during ray development are the following: origin of ray initials from fusiform initials or from cambial ray initials; changes resulting from the intrusive growth of fusiform initials through a group of ray initials and the loss of ray initials from the cambium. From these cellular transformations the most important changes in the origin of secondary rays, increase in height and width and reduction in the height of multisseriate rays are considered.

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Mathematical Modeling of Intrusive Growth of Fusiform Initials in Relation to Radial Growth and Expanding Cambial Circumference in Pinus sylvestris L.

Acta Biotheoretica ◽

10.1007/s10441-009-9068-y ◽

2009 ◽

Vol 57 (3) ◽

pp. 331-348 ◽

Cited By ~ 7

Author(s):

D. Karczewska ◽

J. Karczewski ◽

W. Włoch ◽

J. Jura-Morawiec ◽

P. Kojs ◽

...

Keyword(s):

Mathematical Modeling ◽

Pinus Sylvestris ◽

Radial Growth ◽

Intrusive Growth ◽

Fusiform Initials

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THE ANNUAL CYCLE OF SIZE CHANGES IN THE FUSIFORM CAMBIAL CELLS OF CHAMAECYPARIS AND THUJA

Canadian Journal of Botany ◽

10.1139/b51-040 ◽

1951 ◽

Vol 29 (4) ◽

pp. 421-437 ◽

Cited By ~ 22

Author(s):

M. W. Bannan

Keyword(s):

Annual Cycle ◽

Annual Ring ◽

Growing Season ◽

Fusiform Initials ◽

Cambial Cells ◽

Ray Initials

In stems exceeding a few inches in diameter most of the pseudotransverse divisions involved in the multiplication of fusiform cambial cells occur toward the end of the growing season. Often these aestival transverse divisions are immediately followed by extensive elongation of the new-formed cambial Cells, especially at their overlapping tips. In the succeeding year relatively slight elongation ensues during the development of the first quarter of the annual ring, but through the succeeding quarters the amount of extension increases and is usually maximal in the final quarter. The actual rates of elongation remain undetermined. The multiplication of fusiform initials is accompanied by loss, most of the failure taking place during the last quarter. Generally the fusiform initials with the most extensive ray contacts survive and enlarge, and those with poor ray associations fail or are reduced to potential ray initials. The elongation and multiplication of fusiform initials tend to produce local ray deficiencies. Reduction of the fusiform initials with the poorest ray contacts to ray initials rectifies to varying extent the ray shortages in those areas.

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Does intrusive growth of fusiform initials really contribute to circumferential growth of vascular cambium?

Botany ◽

10.1139/b08-122 ◽

2009 ◽

Vol 87 (2) ◽

pp. 154-163 ◽

Cited By ~ 6

Author(s):

Wiesław Włoch ◽

Joanna Jura-Morawiec ◽

Paweł Kojs ◽

Muhammad Iqbal ◽

Józef Krawczyszyn

Keyword(s):

Tangential Direction ◽

Vascular Cambium ◽

Fusiform Cell ◽

Intrusive Growth ◽

Laburnum Anagyroides ◽

Fusiform Initials ◽

Visible Effect ◽

Symplastic Growth

Currently it is believed that intrusive growth of fusiform cambial initials adds to the circumference of the cambial cylinder: the initial cells multiplied by anticlinal divisions are produced in excess, and the excess cells are later eliminated from the cambial surface. The present study, dealing with the intrusive growth of fusiform initials in the cambium of Laburnum anagyroides Medik, suggests that addition of a radial file of initials owing to intrusive growth, or elimination of any such file, has no visible effect on the tangential dimensions of a given cambial sector, and that intrusive growth of fusiform initials and the elimination of excess initials occur in unison. The two events complement each other, and the gain in size of the growing fusiform cell is accompanied by a reduction in size of its neighbour cell, thus keeping the tangential dimensions of the cambium unchanged. Our findings on L. anagyroides find support from illustrations of previous studies, which we have re-examined and re-interpreted. Our data suggest that increase in the cambial circumference is largely due to the symplastic growth of the fusiform initials in tangential direction.

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Vascular cambium and wood development in Carboniferous plants. III. Arthropitys (Equisetales; Calamitaceae)

Canadian Journal of Botany ◽

10.1139/b86-087 ◽

1986 ◽

Vol 64 (3) ◽

pp. 688-695 ◽

Cited By ~ 11

Author(s):

Michael A. Cichan

Keyword(s):

Cambial Activity ◽

Vascular Cambium ◽

Quantitative Evidence ◽

Wood Development ◽

Ray Cells ◽

Anticlinal Division ◽

Fusiform Initials ◽

Cambium Activity ◽

Developmental Characteristics ◽

Ray Initials

Vascular cambium activity was examined in Arthropitys communis (Binney) Hirmer et Knoell, and A. deltoides Cichan et Taylor, anatomically preserved calamite stems from the Pennsylvanian of Kentucky. Developmental characteristics of the meristem were inferred from changes in the size and number of tracheids and ray cells determined from serial tangential sections of the secondary xylem. In A. communis, circumferential enlargement of the cambium seems to have been accommodated primarily by the enlargement of fusiform initials. Qualitative and quantitative evidence is also presented indicating that “marginal” interfascicular ray initials were converted to fusiform initials during the early stages of cambial activity. In A. deltoides, circumferential enlargement of the meristem was accommodated by the enlargement of fusiform initials and by an increase in size and number of interfascicular ray initials. Multiplicative division of the fascicular ray initials appears to have been an important feature of cambial activity in both species. There is no qualitative or quantitative evidence that the number of fusiform initials in either species was augmented by anticlinal division as in extant seed plants.

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The intrusive growth of initial cells in re-arangement of cells in cambium of Tilia cordata Mill.

Acta Societatis Botanicorum Poloniae ◽

10.5586/asbp.1994.016 ◽

2014 ◽

Vol 63 (2) ◽

pp. 109-116 ◽

Cited By ~ 11

Author(s):

Wiesław Włoch ◽

Ewa Połap

Keyword(s):

Tilia Cordata ◽

Initial Surface ◽

Fusiform Cell ◽

Intrusive Growth ◽

Cambial Cell ◽

Longitudinal Edge ◽

Short Period ◽

A Cell ◽

The One ◽

Cell Reorientation

In the cambium of linden producing wood with short period of grain inclination change (2-4 years), the intensive reorientation of cells takes place. This is possible mainly through an intrusive growth of cell ends from one radial file entering space between tangential walls of neighboring file and through unequal periclinal divisions that occur in the "initial surface". The intrusive growth is located on the longitudinal edge of a fusiform cell close to the end, and causes deviation of cell ends in a neighbouring file from the initial surface. Unequal periclinal division divides a cell with a deviated end into two derivatives, unequal in size. The one of them, which inherits the deviated end, leaves the initial surface becoming a xylem or phloem mother cell. This means that the old end is eliminated. The intensity of intrusive growth and unequal periclinal divisions is decisive for the velocity of cambial cell reorientation. The oriented intrusive growth occurs only in the initial cells. For that reason, changes in cell-ends position do not occur within one packet of cells but are distinct between neighbouring packets.

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