THE RATE OF ELONGATION OF FUSIFORM INITIALS IN THE CAMBIUM OF PINACEAE

1965 ◽  
Vol 43 (4) ◽  
pp. 429-435 ◽  
Author(s):  
M. W. Bannan
Keyword(s):  
Cell Elongation ◽  
Radial Growth ◽  
Ring Width ◽  
Total Width ◽  
Mature Trees ◽  
Cambial Cell ◽  
Anticlinal Division ◽  
Fusiform Initials ◽  
Wide Ring ◽  
Cambial Cells

This report deals with the rate and amount of elongation of fusiform initials in the cycle of cell elongation and multiplication by pseudotransverse division which accompanies circumferential expansion of the cambium. In the recent growth of mature trees the yearly amount of cambial cell elongation drops as ring width decreases, but not in proportion to the decline in ring width. The cumulative elongation through lineal series of cells, per centimeter of xylem increment, increases as ring width decreases. The amount of cell elongation during the production of several narrow rings greatly exceeds that through a single wide ring having the same total width. It seems clear that the time factor is important in the elongation of cambial cells, and to some extent the interrelated frequency of anticlinal division, particularly when radial growth declines.

CELL LENGTH AND RATE OF ANTICLINAL DIVISION IN THE CAMBIUM OF THE SEQUOIAS

1966 ◽  
Vol 44 (2) ◽  
pp. 209-218 ◽  
Author(s):  
M. W. Bannan
Keyword(s):  
Cell Elongation ◽  
Ring Width ◽  
Cell Length ◽  
Sequoia Sempervirens ◽  
High Rate ◽  
Cambial Cell ◽  
Anatomical Features ◽  
Anticlinal Division ◽  
Cambial Cells

This report deals with the frequency of anticlinal (multiplicative) divisions in fusiform cambial cells, cell length at the time of division, and ring width as determined mostly in Sequoia sempervirens. The general relationships between these anatomical features resembled those observed in other conifers, but the frequency of anticlinal division was relatively high and the cells were long. Accordingly, the rate of cambial cell lengthening in the repetitive cycle of anticlinal division and cell elongation was found to exceed that in other conifers. Upward in the lower part of the stem the rate of anticlinal division decreased and cell length increased. A comparatively high rate of anticlinal division was maintained in the peripheral growth of large boles in both species, but cell length was greater in S. sempervirens than in S. gigantea.

SPIRAL GRAIN AND ANTICLINAL DIVISIONS IN THE CAMBIUM OF CONIFERS

1966 ◽  
Vol 44 (11) ◽  
pp. 1515-1538 ◽  
Author(s):  
M. W. Bannan
Keyword(s):  
High Ratio ◽  
Contributory Factor ◽  
Relative Duration ◽  
Mature Trees ◽  
Spiral Grain ◽  
Anticlinal Division ◽  
Fusiform Initials ◽  
The Mean ◽  
Cambial Cells ◽  
The Right

In the cambium of mature trees a general conformity was found in the orientation of the partition in the pseudotransverse division of fusiform initials through out sectors of varying size. The proportion of divisions deviating from the preferred orientation varied with the tree, the locality, and the species, but was usually less than 10%. As radial accretion followed, periodic reversals occurred in the orientation of anticlinal divisions, the spacing between reversals, in terms of xylem increment, being related to the frequency of anticlinal division. The mean interval shortened as the rate of division rose according to the equation xy = k. While this overall relationship obtained, there was generally some inequality in the relative duration of leftward and rightward orientations of division. In species with grain in the outer wood slanted to the right, a rightward tilt of division persisted for longer periods than a leftward tilt. Conversely, in species with grain slanted to the left, thickness of xylem showing leftward orientation of multiplicative divisions exceeded that with rightward orientation. Changes associated with growth from sapling to adult were studied in Picea, in which genus grain is usually to the left in the inner wood and to the right in the outer wood. Here multiplicative divisions were usually inclined to the left in the growth of the first few years, whereas in the later growth orientation to the right endured for longer periods than to the left. Both orientation of pseudo-transverse division and direction of cell elongation after division seem to be under a general polar control. This apparently is an important element in the induction of spiral grain. Above-average net gain of fusiform initials in the turmoil of cell addition and loss, which accompanies circumferential expansion, may be a contributory factor. Serving to restrain the development of an excessive spirality are periodic reversals in direction of tilt in anticlinal division, and a high ratio of loss of cambial cells relative to the frequency of anticlinal division.

TRACHEID SIZE AND RATE OF ANTICLINAL DIVISION IN THE CAMBIUM OF CUPRESSUS

1963 ◽  
Vol 41 (8) ◽  
pp. 1187-1197 ◽  
Author(s):  
M. W. Bannan
Keyword(s):  
Arid Regions ◽  
Ring Width ◽  
Cell Length ◽  
Small Cells ◽  
Cell Multiplication ◽  
Mature Trees ◽  
Cambial Cell ◽  
Interspecific Differences ◽  
Anticlinal Division ◽  
Maximum Cell

Differences of considerable magnitude occur in the tracheid dimensions of North American species of Cupressus. In general the species in arid regions (C. arizonica, C. glabra, C. forbesii, and C. macnabiana) have smaller cells than the species in more humid localities (C. macrocarpa and C. pygmaea). Minor, in some cases questionably significant, differences in cell size are found at different sites for the same species. Noteworthy interspecific differences exist in the frequency of anticlinal (pseudotransverse) divisions involved in cambial cell multiplication. On the whole, these divisions take place at a faster rate in the species with small cells (C. arizonica, C. macnabiana) than in species with large cells (C. pygmaea). Some general relationships between rate of growth, frequency of pseudotransverse divisions, and cell length are also evident. In the stems of mature trees, maximum cell length is apparently associated with a ring width of approximately 1–1.5 mm. Reduction in ring width is accompanied by a rise in frequency of pseudotransverse division and a slight recession in cell length. Widening of the rings produces no change in the rate of anticlinal division, in relation to linear radial accretion, but cell length declines. The orientation of the partition in pseudotransverse division is usually unidirectional in neighboring cells, but reversals in tilt occur after varied intervals. Duration of the interval between reversals shows an inverse relationship with the frequency of pseudotransverse division.

RAY CONTACTS AND RATE OF ANTICLINAL DIVISION IN FUSIFORM CAMBIAL CELLS OF SOME PINACEAE

1965 ◽  
Vol 43 (5) ◽  
pp. 487-508 ◽  
Author(s):  
M. W. Bannan
Keyword(s):  
Cell Multiplication ◽  
Cambial Cell ◽  
Intrinsic Factors ◽  
Ray Parenchyma ◽  
Ray Cells ◽  
Anticlinal Division ◽  
Fusiform Initials ◽  
Ray Parenchyma Cells ◽  
Cambial Cells ◽  
Resin Canals

The frequency of pseudotransverse divisions involved in cambial cell multiplication was found to be slightly higher in fusiform initials bordering on fusiform rays than in other cambial cells. The extent of difference was greater in Pinus than in Pseudotsuga or Picea. Because of the larger size of fusiform rays as compared to uniseriate rays, cambial cells adjoining the former were in contact with more ray cells per millimeter of cell length than cambial cells touching only uniseriate rays. As with the frequency of pseudotransverse division, the margin of difference in extent of ray contact was greater in Pinus than in Pseudotsuga or Picea. The evidence therefore indicates that the higher rate of pseudotransverse division in cambial cells adjoining fusiform rays was correlated with the greater area of ray contact, or more specifically, the increased contact with ray parenchyma cells. The higher rate of anticlinal division was apparently the consequence of an increase in ratio of survival of daughter initials arising in pseudotransverse division, some of the smaller newly formed initials persisting in contrast to the usual failure of similar initials situated elsewhere in the cambium. Mean height of uniseriate rays tended to increase with widening of the annual rings, but the size of fusiform rays was influenced to a much smaller degree. The frequency of fusiform rays, and horizontal resin canals, showed no consistent relationship with growth rate, but appeared to be determined by intrinsic factors.

SEQUENTIAL CHANGES IN RATE OF ANTICLINAL DIVISION, CAMBIAL CELL LENGTH, AND RING WIDTH IN THE GROWTH OF CONIFEROUS TREES

1967 ◽  
Vol 45 (8) ◽  
pp. 1359-1369 ◽  
Author(s):  
M. W. Bannan
Keyword(s):  
Cell Size ◽  
Ring Width ◽  
Cell Length ◽  
Annual Increment ◽  
Cambial Cell ◽  
Cell Dimensions ◽  
Anticlinal Division ◽  
Cambial Cells ◽  
Uniform Ring ◽  
Tree Development

The early growth of a tree is marked by a widening of the annual increments, a deceleration in rate of multiplicative (anticlinal) division of fusiform cambial cells, and an increase in cell length. Distance outward from the pith at which maximation in cell size occurs, and subsequent trends in cell dimensions, are apparently modified by rate of growth. Continuation of a uniform ring width through the middle to late years favors comparative constancy in rate of anticlinal division and cell size during that stage of tree development. Reduction in amount of annual increment in the late growth to the width optimal for cell extension, about 1 mm, induces a delayed and probably heightened maximation in cell length. Continued lessening in radial growth to an annual accretion of 0.5 mm or less, with the onset of senility, results in acceleration in rate of multiplicative division and reduction in cell length.

SOME ASPECTS OF THE ELONGATION OF FUSIFORM CAMBIAL CELLS IN THUJA OCCIDENTALS L.

1956 ◽  
Vol 34 (1) ◽  
pp. 175-196 ◽  
Author(s):  
M. W. Bannan
Keyword(s):  
Tip Growth ◽  
Local Environment ◽  
Growth Cycle ◽  
Minor Role ◽  
Mature Trees ◽  
Neighboring Cell ◽  
Fusiform Initials ◽  
Cambial Cells ◽  
A Minor ◽  
High Degree

An outstanding feature of the elongation of fusiform initials is the high degree of variability that exists from cell to cell. This individual inconstancy is to some extent related to recurrent alterations in the local environment. Thus loss of a neighboring cell often results in accelerated elongation. Although frequently masked by the deviations in individual cells, certain general trends of growth become apparent on analysts of the data from numerous cells. In the growth cycle between successive multiplicative divisions the progress of elongation is not uniform but rather follows a familiar growth pattern, early rapid extension giving way to a gradually decreasing rate of elongation as lengthening proceeds. Growth at opposite ends of the same cell is usually dissimilar, basipetal extension tending to predominate. This bipolar difference is evident in the stems of small trees, in the periphery of the stems of mature trees, in the distal parts of branches, and to a lesser degree, in the proximal parts of recurved branches. The reduced bipolar difference in the inverted proximal portions of recurved branches indicates that gravity is not the major factor in the establishment of polarity, but does perhaps play a minor role. Cell elongation is apparently achieved by tip growth.

FURTHER OBSERVATIONS ON THE REDUCTION OF FUSIFORM CAMBIAL CELLS IN THUJA OCCIDENTALIS L.

1953 ◽  
Vol 31 (1) ◽  
pp. 63-74 ◽  
Author(s):  
M. W. Bannan
Keyword(s):  
Cell Division ◽  
Cell Volume ◽  
Cell Shape ◽  
Transitional Period ◽  
Radial Expansion ◽  
Cambial Cell ◽  
Thuja Occidentalis ◽  
Daughter Cells ◽  
Fusiform Initials ◽  
Cambial Cells

The multiplication of fusiform initials in the cambium is accompanied by extensive loss or transformation of these cells. A few of the failing cambial cells lapse into maturation quickly, but the majority are transversely subdivided with varying proportions of the segments surviving and undergoing ultimate conversion to ray initials. The loss or conversion is attended with reduction in cell size. Increase in cell volume lags behind cell division during the periclinal divisions of the transitional period. The tangential dimensions of the successively formed cells are continuously reduced, and sometimes radial expansion is also retarded, especially toward the cell tips. Simultaneous shortening of the cells is due to alteration in cell shape combined with asymmetry in periclinal division such that daughter cells of unequal lengths are produced. Repetition of the process, the smaller cell functioning as the initiating cambial cell in each instance, results in continued shortening.

CAMBIAL BEHAVIOR WITH REFERENCE TO CELL LENGTH AND RING WIDTH IN THUJA OCCIDENTALIS L.

1960 ◽  
Vol 38 (2) ◽  
pp. 177-183 ◽  
Author(s):  
M. W. Bannan
Keyword(s):  
Ring Width ◽  
Growth Patterns ◽  
Cell Length ◽  
Cell Multiplication ◽  
Radial Increment ◽  
Cambial Cell ◽  
Thuja Occidentalis ◽  
Profound Influence ◽  
Fusiform Initials ◽  
The Relationship

The relationship between ring width and length of wood cells was studied by reference to mature white cedar trees of various growth patterns. These included trees of similar diameter but diverse growth rates, trees with transition from wide to narrow rings or from narrow to wide rings in their peripheral growth, and trees with rings varying in width in different radii. Although much fluctuation occurred among individuals there was in general an inverse relationship between cell length and ring width. On the other hand, the variations in frequency of pseudotransverse divisions in the cambium, which might be expected to have a profound influence on cell length because of their involvement in cambial cell multiplication, were not obviously related to the growth rate. The frequency of pseudotransverse divisions in the fusiform initials apparently is geared neither to circumferential expansion nor to number of periclinal divisions in the cambium but rather seems to be related simply to linear radial increment.

RING WIDTH, TRACHEID SIZE, AND RAY VOLUME IN STEM WOOD OF THUJA OCCIDENTALIS L.

1954 ◽  
Vol 32 (3) ◽  
pp. 466-479 ◽  
Author(s):  
M. W. Bannan
Keyword(s):  
Ring Width ◽  
Cambial Activity ◽  
Thuja Occidentalis ◽  
Stem Wood ◽  
Rate Of Growth ◽  
Fusiform Initials ◽  
Similar Range ◽  
Cambial Cells ◽  
Rates Of Growth

The interrelations between varied growth rates and those phases of cambial activity involved in determination of tracheid size and ray volume were investigated in Thuja occidentalis. Length of tracheids at the time of pseudotransverse division of the initiating cambial cells was determined from the peripheral wood of stems which fell within a similar range of size but differed in their rates of growth. The circumstances which favored accelerated growth, as shown in more frequent periclinal divisions in the cambium, encouraged earlier pseudotransverse division of fusiform initials and hence the production of shorter tracheids. Among trees of similar size decline in growth rate was accompanied by lengthening of cambial cells to a maximum associated with annual radial increments of 0.7 to 0.8 mm. Tracheid diameter was only slightly influenced by the rate of growth. Tangential width underwent minor increase in suppressed trees and radial diameter was slightly augmented in fast-growing trees. A positive correlation was revealed between ray volume and rate of growth.

scholarly journals The Impact of Changing Climate on the Cambial Activity during Radial Growth in Some Citrus Species

2021 ◽  
Author(s):  
Moin Ahmad Khan ◽  
M. Badruzzaman Siddiqui
Keyword(s):  
Radial Growth ◽  
Cambial Activity ◽  
Age Effects ◽  
Vascular Cambium ◽  
Citrus Species ◽  
The Third ◽  
Changing Climate ◽  
Fusiform Initials ◽  
Cambial Cells ◽  
The Impact

This study on radial growth in the stem of Citrus was carried out with an aim to notice the behavior of vascular cambium with respect to climatic and age effects. The fusiform initials vary in length from 137 to 363 μm in C. limon, 100 to 463 μm in C. paradisi, 137 to 413 μm in C. reticulata var. kinnow, and 137 to 375 μm in C. sinensis. The length rises with age, followed by decline and then again increase in C. limon. In C. paradisi, there is increase up to maximum and after decline is soon followed by constancy. In C. reticulata var. kinnow, increase in length from top to base in C. sinensis, increase up to maximum followed by a decline. Swelling of cambial cells occurs in the third week of March in C. limon, last week of March in C. paradisi, third week of April in C. reticulata var. kinnow, and second week of April in C. sinensis. The cambium turns dormant in early October in C. limon, late December in C. paradisi, early December in C. reticulata var. kinnow, and early November in C. sinensis. Thus, the cambium remains active for about 6 months in C. limon and C. sinensis, 9 months in C. paradisi, and 7 months in C. reticulata var. kinnow.

Sign in / Sign up

Export Citation Format

Share Document