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.

Cambial activity and ray cell abundance in Acer saccharum

1977 ◽  
Vol 55 (20) ◽  
pp. 2559-2564 ◽  
Author(s):  
R. A. Gregory
Keyword(s):  
Growth Rate ◽  
Acer Saccharum ◽  
Unit Area ◽  
Ring Width ◽  
Cambial Activity ◽  
Relative Volume ◽  
Annual Ring Width ◽  
Ray Cells ◽  
Fusiform Initials ◽  
Ray Cell

The ratio of ray and ray cell initials to fusiform initials of the vascular cambium relative to radial growth rate as reflected in the secondary xylem was studied in stems of Acer saccharum Marsh. Ray initials increased in size as they aged, slowly when growth rate was low, rapidly when it was high, but there was little fluctuation in the number of rays per unit of tangential area; as the cambium increased in circumference, the older, larger rays diverged and new small rays arose in intervening areas, thus maintaining a uniform unit area population independent of growth rate. However, since ray size increased rapidly when growth rate was high, the unit area population of ray cells rose abruptly with accelerating growth rate: the relative volume of xylem ray tissue rose from 8.6 to 12.7% of the total xylem volume when annual ring width increased from 1 to 7 mm. When fast growth was not maintained, the unit area population of ray cells declined slowly as the large rays diverged.

CAMBIAL BEHAVIOR WITH REFERENCE TO CELL LENGTH AND RING WIDTH IN PINUS STROBUS L.

1962 ◽  
Vol 40 (8) ◽  
pp. 1057-1062 ◽  
Author(s):  
M. W. Bannan
Keyword(s):  
Inverse Relationship ◽  
Ring Width ◽  
Pinus Strobus ◽  
Growth Patterns ◽  
Cell Length ◽  
Annual Rings ◽  
Forest Types ◽  
Thuja Occidentalis ◽  
Cambial Cells ◽  
Individual Trees

The relationships between width of annual rings, length of wood cells, and frequency of anticlinal (multiplicative) divisions in fusiform cambial cells were studied by reference to trees of various growth patterns. The trees selected ranged from 8 to 20 in. diameter and included both open-grown specimens with branches close to the ground and forest types with tall, slender shafts. Much fluctuation was noted among individual trees, but in general there was, in the peripheral growth, an inverse relationship between length of wood cells and width of annual rings. The frequency of anticlinal divisions in the cambium remained at a more or less uniform rate in trees with rings from 1.5 to 5 mm wide, but rose sharply when ring width fell below 1.3 mm. This was in contrast to the situation observed earlier in Thuja occidentalis where the rise in frequency of anticlinal divisions was slight and occurred only in trees with rings less than 0.3 mm wide.

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.

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.

THE VASCULAR CAMBIUM AND RADIAL GROWTH IN THUJA OCCIDENTALIS L

1955 ◽  
Vol 33 (1) ◽  
pp. 113-138 ◽  
Author(s):  
M. W. Bannan
Keyword(s):  
Secondary Xylem ◽  
Cambial Activity ◽  
Vascular Cambium ◽  
Mature Trees ◽  
General Sense ◽  
Thuja Occidentalis ◽  
Steady Rate ◽  
Cambial Cells ◽  
The One ◽  
Mother Cells

The vascular cambium, to use the term in the general sense as designation for the entire meristem producing secondary xylem and phloem, consists of the self-perpetuating uniseriate initiating layer and the derived tissue mother cells. In the dormant condition the cambium in the stems of mature trees is one to four, usually two to three, cells wide. The one to three tangential tiers of cells toward the xylem are made up of xylem mother cells, and the single tier next the phloem is composed of initial cells. On reactivation all cambial cells expand radially. Periclinal divisions soon follow, usually according to a sequence in which the xylem mother cells in the tier contiguous to the late wood are the first to divide and the initial cells last, although some variation occurs. The zone of periclinal division rapidly widens to 100-300 μ in vigorous open-grown trees, the center of activity during this vernal surge of growth clearly being among the dividing and redividing xylem mother cells. Thereafter, from mid-June to August, a continued decline in cell production follows as the zone of xylem mother cells decreases from many tangential rows to few. The initiating layer becomes relatively more important as the center of cell generation, and toward the end of the growing season the initial cells undergo those changes which modify the cellular pattern of the cambium and hence of the derived tissues. Phloem development begins later than that of xylem, and at the end of May the new phloem varies from none to four cells as compared with a xylemward production of 30-60 cells in vigorous trees. Phloem expansion continues at a more or less steady rate from June to the termination of cambial activity in August or early September. The annual phloem increments vary less in width than those of xylem.

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.

THE RELATIVE FREQUENCY OF THE DIFFERENT TYPES OF ANTICLINAL DIVISIONS IN CONIFER CAMBIUM

1957 ◽  
Vol 35 (6) ◽  
pp. 875-884 ◽  
Author(s):  
M. W. Bannan
Keyword(s):  
Relative Frequency ◽  
Small Cells ◽  
Rate Of Growth ◽  
Different Types ◽  
Anticlinal Division ◽  
Fusiform Initials ◽  
Cambial Cells ◽  
Mother Cells ◽  
Ray Initials

The fusiform cambial cells of conifers undergo two types of anticlinal division, pseudotransverse division and division to produce small cells off the side. Pseudotransverse divisions are largely confined to the cambial initials, only a small percentage of such divisions occurring in the derived tissue mother cells. The incidence of pseudotransverse divisions outside the layer of initials tends to rise with the rate of growth. Divisions of the second type, to yield segments off the side, are infrequent and seem generally to involve only the fusiform initials. Behavior of the abscissed segments bears some relationship to size, the shortest segments usually failing, those of intermediate length tending to become reduced to one or more ray initials, and the largest developing as fusiform initials.

Drought signals inferred from ring-width and stable carbon isotope chronologies from Thuja occidentalis trees growing at their northwestern distribution limit, central Canada

2012 ◽  
Vol 42 (3) ◽  
pp. 517-531 ◽  
Author(s):  
Robert Au ◽  
Jacques C. Tardif
Keyword(s):  
Tree Ring ◽  
Tree Rings ◽  
Stable Carbon Isotopes ◽  
Stable Carbon Isotope ◽  
Ring Width ◽  
Ring Formation ◽  
Moisture Regime ◽  
Stable Carbon ◽  
Thuja Occidentalis ◽  
Central Canada

Stable carbon isotopes (δ13C) fixed in tree rings are dependent upon environmental conditions. Old northern white-cedar ( Thuja occidentalis L.) trees were sampled at their northwestern limit of distribution in central Canada. The objectives of the study were (i) to investigate the association between tree-ring δ13C values and radial growth in addition to the response of these variables to climate, (ii) to assess site differences between two sites varying in moisture regime, and (iii) to compare tree-ring δ13C of T. occidentalis with that of other boreal tree species growing at the northern limit of their distribution in central Canada. Over 2500 tree rings comprised of 15 T. occidentalis trees were analyzed for δ13C. Annually resolved δ13C (1650–2006) and ring-width (1542–2006) chronologies were developed. During the year of ring formation, ring width was associated with spring and early-summer conditions, whereas δ13C was more indicative of overall summer conditions. However, compared with δ13C values, ring width was more often associated with climate conditions in the year prior to ring formation. Conditions conducive to moisture stress were important for both parameters. Although ring width and δ13C corresponded to the drought intervals of the 1790s, 1840s, 1890s, 1930s, and 1960–1970, ring width may be more responsive to prolonged drought than δ13C. Tree-ring δ13C could, however, provide important information regarding physiological adaptations to drought.

scholarly journals Crystallographic structure of the turbine C-ring from spinach chloroplast F-ATP synthase

2014 ◽  
Vol 34 (2) ◽  
Author(s):  
Asha Manikkoth Balakrishna ◽  
Holger Seelert ◽  
Sven-Hendric Marx ◽  
Norbert A. Dencher ◽  
Gerhard Grüber
Keyword(s):  
Atp Synthase ◽  
Ring Width ◽  
Atp Synthesis ◽  
Crystallographic Structure ◽  
Unit Cell Parameters ◽  
Subunit C ◽  
Cell Parameters ◽  
Ring Diameter ◽  
C Subunit

In eukaryotic and prokaryotic cells, F-ATP synthases provide energy through the synthesis of ATP. The chloroplast F-ATP synthase (CF1FO-ATP synthase) of plants is integrated into the thylakoid membrane via its FO-domain subunits a, b, b’ and c. Subunit c with a stoichiometry of 14 and subunit a form the gate for H+-pumping, enabling the coupling of electrochemical energy with ATP synthesis in the F1 sector. Here we report the crystallization and structure determination of the c14-ring of subunit c of the CF1FO-ATP synthase from spinach chloroplasts. The crystals belonged to space group C2, with unit-cell parameters a=144.420, b=99.295, c=123.51 Å, and β=104.34° and diffracted to 4.5 Å resolution. Each c-ring contains 14 monomers in the asymmetric unit. The length of the c-ring is 60.32 Å, with an outer ring diameter 52.30 Å and an inner ring width of 40 Å.

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