SEASONAL GROWTH CHARACTERISTICS OF LONG AND SHORT SHOOTS OF TAMARACK

1967 ◽  
Vol 45 (9) ◽  
pp. 1643-1651 ◽  
Author(s):  
J. Johanna Clausen ◽  
T. T. Kozlowski
Keyword(s):  
Seasonal Changes ◽  
Stem Elongation ◽  
Growth Characteristics ◽  
Weight Increase ◽  
Stem Length ◽  
Larix Laricina ◽  
Seasonal Growth ◽  
Long Shoots ◽  
Short Shoots ◽  
Food Reserves

Tamarack (Larix laricina (DuRoi) K. Koch) produces long shoots which bear two kinds of needles. Early needles are present in the bud and elongate rapidly after budbreak. Late needles, few of which are present in the bud, elongate later than early needles. Short shoots bear early needles only, and stem length seldom exceeds 1 mm. Seasonal changes in length and weight of needles and stems of both shoot types were measured. In long shoots, 75% of stem elongation, more than 70% of stem weight increment, and 65–70% of late needle elongation occurred after early needles were full-sized. Stem and late needle elongation ceased simultaneously, after which time needle weight decreased and stem weight increased. Early needles probably drew on food reserves while developing, and then themselves contributed to stem and late needle elongation. Final stem weight increase probably used photosynthate from both late and early needles of the current year.Shading of current and last year's needles showed that shoots in which photosynthesis was interrupted in this way produced shorter, lighter-weight stems than did control shoots.

Crown architecture of Larix laricina saplings: an analysis of higher order branching

1987 ◽  
Vol 65 (2) ◽  
pp. 268-279 ◽  
Author(s):  
W. R. Remphrey ◽  
G. R. Powell
Keyword(s):  
Simulation Modelling ◽  
Shoot Length ◽  
Larix Laricina ◽  
Structural Development ◽  
Short Shoot ◽  
Lateral Buds ◽  
Architectural Patterns ◽  
Long Shoots ◽  
Short Shoots ◽  
Terminal Shoot

Quantitative analysis and simulation modelling of Larix laricina (Du Roi) K. Koch branches revealed a complex system of architectural patterns and correlations. Numbers of lateral buds and long shoots were positively correlated with parent-shoot length, but the relationships varied among shoot orders and for sylleptic shoots. For order 2 and sylleptic shoots, numbers of lateral long shoots were also correlated with associated terminal-shoot lengths. Sylleptic shoots produced more lateral long shoots than equivalent proleptic shoots. Lateral long-shoot lengths decreased basipetally and were correlated with terminal-shoot lengths. Lengths of order 2 lateral long shoots also varied independently with crown position. Generally, the degree of apical control decreased and the proportion of short shoots increased with positions of less vigour in the crown. Terminal long-shoot lengths varied with parent-shoot length, location, and to some extent parent-axis leader length. Terminal short-shoot production was associated with shorter parent shoots. Shorter order 2 shoots (<60 mm) and most order 3 shoots produced no lateral long shoots. The net result was that branch structural development ceased in less vigorous crown positions. The spatial disposition of shoots, as defined by elevation and divergence angles, varied with position of origin around and along parent shoots. Although variable, elevation angles decreased and divergence angles increased basipetally.

Shoot development in Betula papyrifera. IV. Comparisons between growth characteristics and expression of vegetative long and short shoots

1984 ◽  
Vol 62 (3) ◽  
pp. 446-453 ◽  
Author(s):  
J. Cartey Caesar ◽  
Alastair D. Macdonald
Keyword(s):  
Growth Rates ◽  
Stem Elongation ◽  
Morphological Characteristics ◽  
Axillary Buds ◽  
Betula Papyrifera ◽  
Short Shoot ◽  
Relative Growth ◽  
Relative Growth Rates ◽  
Long Shoots ◽  
Short Shoots

Postflush observations on shoots of Betula papyrifera Marsh. indicated that long and short shoots differ in a range of morphological characteristics. Long shoots developed from distal axillary buds and short shoots developed from proximal axillary buds on the previous year's long shoots. Consequently, the potential of a bud to develop into a long shoot decreased basipetally. Potential long-shoot buds had higher bud-relative growth rates, stem-relative growth rates, leaf-relative growth rates, and stem dry weights during the course of postflush growth. Changes in leaf thickness, expressed in terms of specific leaf area and specific leaf weight, indicated that long shoots temporarily had thinner leaves than did short shoots a few weeks after flushing. Net assimilate requirements in long shoots for late leaf and internodal expansion may explain these observations. Nearing maturity, long-shoot early leaves became thicker, possibly owing to greater shoot vigour and (or) higher photosynthetic efficiency. Consequently, mature long-shoot early leaves possessed larger and thicker laminae, longer petioles, more side nerve pairs, and tended to grow more in length than width than short-shoot leaves on shoots of comparable age. Leaves of older short shoots, 2–10 years old, attained a greater size and had longer petioles than those of 1-year-old short shoots. Stem elongation and the development and expression of leaves in long shoots seemed to have a correlative influence on the overall vigour of long shoots.

scholarly journals Morphology of Two-year-old Limb Sections and Mid-season Spur Quality of Four Apple Cultivars on Five Dwarfing Rootstocks

HortScience ◽  
1997 ◽  
Vol 32 (3) ◽  
pp. 506D-506
Author(s):  
W. Alan Erb ◽  
David C. Ferree ◽  
Frank D. Morrison ◽  
Mark Pyeatt ◽  
Richard Ryer
Keyword(s):  
Leaf Area ◽  
Leaf Size ◽  
Stem Length ◽  
Stem Density ◽  
Sectional Area ◽  
Cross Sectional ◽  
Long Shoots ◽  
Apple Cultivars ◽  
Short Shoots

This study was conducted at three locations (Manhattan, Kan.; Wichita, Kan.; Wooster, Ohio) for 3 years (1994–1996). At bloom, 2-year-old limb sections from `Smoothee', `Jonagold', `Empire', and `Rome' on M.9EMLA, Bud 9, Mark, Ottawa 3, or M.26EMLA were evaluated for flowering and vegetative, spurs (5 cm or less), short shoots (5–15 cm) and long shoots (>15 cm). In mid-August, spur quality was estimated by randomly selecting five spurs per cultivar rootstock combination. There were significant location and year differences for all the morphological and spur quality characters measured. Across locations and years, the following characteristics were consistently high for the cultivars listed: stem density of flowering spurs for `Empire'; and leaf area, bud-diameter and average leaf size per spur for `Jonagold'. The most consistently high characteristics across locations and years for the rootstocks were for stem density of flowering spurs for Mark and leaf number, leaf area, bud-diameter, and average leaf size per spur for M.26EMLA. Stem density for flowering short shoots was highest for `Smoothee' and M.9EMLA in Wooster, `Jonagold' and Bud 9 in Wichita and `Rome', `Jonagold', and Bud 9 in Manhattan. Flowering long shoot stem density was highest for `Smoothee', `Jonagold', and M.26EMLA in Wooster, `Smoothee' in Wichita, and `Jonagold' and Ottawa 3 in Manhattan. There were some significant cultivar by rootstock interactions. The most-consistent interactions across locations and years were for stem cross-sectional area, stem length, stem density of flowering spurs, and flowering short shoots and bud-diameter per spur.

Yield and seasonal growth flushing of Protea 'Pink Ice' and Leucadendron 'Silvan Red' in South Australia

1996 ◽  
Vol 36 (7) ◽  
pp. 869 ◽  
Author(s):  
GE Barth ◽  
NA Maier ◽  
JS Cecil ◽  
WL Chyvl ◽  
MN Bartetzko
Keyword(s):  
Growth Rate ◽  
Stem Elongation ◽  
South Australia ◽  
Annual Growth ◽  
Stem Length ◽  
Seasonal Growth ◽  
Fertile Soil ◽  
Plant Data ◽  
Low Levels

Data on yield and growth flushing of 2 protea varieties were collected at commercial sites in South Australia over 3 years. Mean (� s.e.) yield of Protea 'Pink Ice' in terms of marketable stems averaged 63 (�) stems/plant on a highly fertile soil to 39 (�1) stemslplant on an infertile site. On the same sites, Leucadendron 'Silvan Red' yielded means (�se.) of 314 (�13) and 219 (�5) marketable stems/plant. Data are presented in marketing classes based on stem length. Monthly increases in stem length and diameter were used to determine seasonal growth flushing patterns in the 2 cultivars. Pink Ice commenced annual growth in August-September, reached peak growth rate in October and fell to low levels in December. Silvan Red commenced growth between October and November, reached peak growth rate in December and continued stem elongation until March when all growth ceased until the following year.

Crown architecture of Larix laricina saplings: quantitative analysis and modelling of (nonsylleptic) order 1 branching in relation to development of the main stem

1984 ◽  
Vol 62 (9) ◽  
pp. 1904-1915 ◽  
Author(s):  
W. R. Remphrey ◽  
G. R. Powell
Keyword(s):  
Morphological Variability ◽  
Natural Populations ◽  
Height Growth ◽  
Main Stem ◽  
Larix Laricina ◽  
Crown Architecture ◽  
Growth Increments ◽  
Long Shoots ◽  
Architectural Models ◽  
Short Shoots

The upper 5 years of crown growth in samples of Larix laricina (Du Roi) K. Koch (tamarack) saplings from natural populations in the Fredericton, N.B., area provided data to model architectural relationships describing patterns of (nonsylleptic) order 1 branching in relation to development of the main stem. The model was based on relationships between branch extension and height growth, and numbers and positions of order 1 branches. Elevation angles of shoots making up the branches, and conversion of order 1 long shoots to order 1 short shoots were also incorporated. Lengths of current shoots of major order 1 branches tended to decrease with increasing depth in the crown. Similar tendencies occurred among lengths of all current branch extensions within single height-growth increments, but the decreases in length became less regular with increasing age of branch. Because the relationships were complex, alternative approaches to modelling shoot lengths were adopted to enhance understanding of the patterns involved. Deterministic and stochastic elements were used in the overall model to account for significant proportions of morphological variability. Simulations based on the alternatives within the model were realistic in their interpretations of actual sapling crown architecture. Classification of L. laricina according to previously proposed architectural models that qualitatively describe general development was discussed.

Crown architecture of Larix laricina saplings: production and disposition of foliage and their simulation

1988 ◽  
Vol 66 (11) ◽  
pp. 2234-2246 ◽  
Author(s):  
W. R. Remphrey ◽  
G. R. Powell
Keyword(s):  
Simulation Models ◽  
Larix Laricina ◽  
Short Shoot ◽  
First Order ◽  
Growth Increments ◽  
Rate Of Increase ◽  
Long Shoots ◽  
Short Shoots ◽  
Successive Generations ◽  
The Relationship

In saplings of Larix laricina (Du Roi) K. Koch (tamarack), correlations between projected leaf area (PLA) and architectural variables such as shoot length and shoot age were incorporated into existing simulation models to estimate the distribution of PLA in the crown according to several spatial, temporal, and morphological parameters. After five generations of simulated shoot growth, PLA values ranged from 8.2 m2 for trees with short height growth increments (HGIs) and no syllepsis to 25.5 m2 for those with long HGIs and heavy syllepsis. Although PLA increased, the rate of increase declined over time. In early simulated generations, long-shoot PLA predominated. In the fifth simulated generation, short shoots bore about 75% of the PLA. There was a basipetal increase in PLA by HGI, but the relationship was nonlinear. In trees with syllepsis, sylleptic origin branches on individual HGIs carried more PLA than concomitant proleptic branches for 1 year but thereafter the proportions were reversed. Over successive generations, the contribution of different branch orders to the total PLA shifted from mostly first-order long shoots (including PLA on daughter short-shoot axes) to second-order shoots carrying more than 50% by year 5. Because of the short-shoot contribution, there was considerable PLA in all regions of the crown, although the greatest concentration was in lower regions of midconic zones. Simulated PLA index increased substantially with crown development. Trees with short HGIs had the greatest PLA index and those with long HGIs had the least.

Occurrence and distribution of cones borne laterally on long shoots of Larix laricina

1984 ◽  
Vol 62 (4) ◽  
pp. 771-777 ◽  
Author(s):  
G. R. Powell ◽  
Kathleen J. Tosh ◽  
W. R. Remphrey
Keyword(s):  
Larix Laricina ◽  
Short Shoot ◽  
Shoot Buds ◽  
First Order ◽  
Long Shoots ◽  
Short Shoots

Trees of Larix laricina (Du Roi) K. Koch reaching the stage of first cone bearing tended to produce the majority of their seed cones, and many of their pollen cones, in lateral (axillary) positions along long shoots. In subsequent cone bearing, a greater proportion of the cones occurred in the typical (for the genus) position terminating short shoots. Some trees 2 to 4 m tall bore over 500 lateral seed cones. Lateral cones occurred on all kinds of long shoots, except sylleptic first-order shoots, produced in the 3-year-old portion of the crown. Lateral seed cones were borne on the morphogenically proximal halves of the long shoots and on all surfaces around the circumference of the shoots, but they were less frequent on upper surfaces than on other surfaces. Lateral pollen cones occurred in the proximal 10% of the lengths of the bearing shoots and were restricted to the undersurfaces or sides of the shoots. Lateral cone buds were distinctively larger and contained more bud scales than adjacent lateral short-shoot buds.

scholarly journals Response of Oxypetalum caeruleum to Irradiance, Temperature, and Photoperiod

1990 ◽  
Vol 115 (6) ◽  
pp. 910-914 ◽  
Author(s):  
A.M. Armitage ◽  
N.G. Seager ◽  
I.J. Warrington ◽  
D.H. Greer ◽  
J. Reyngoud
Keyword(s):  
Stem Elongation ◽  
Net Photosynthesis ◽  
Stem Length ◽  
Photon Flux ◽  
Vase Life ◽  
Photosynthetic Photon Flux ◽  
Node Number ◽  
Stem Strength ◽  
Flower Abortion ◽  
Reduced Time

Incremental increases in temperature from 14 to 22 to 30C resulted in linear increases in stem length and node number and decreases in stem diameter and stem strength of Oxypetalum caeruleum (D. Don.) Decne. Higher temperatures also resulted in additional flower abortion, reduced time to flowering, and fewer flowering stems per inflorescence. Reduction in the photosynthetic photon flux (PPF) from 695 to 315 μmol·s-1·m-2 had similar effects as increasing the temperature on vegetative characteristics, but had little effect on reproductive ones. The rate of stem elongation was greatest at low PPF for all temperatures and at high temperature for all PPF treatments. Net photosynthesis rose between 14 and 22C and declined at 30C for all PPF treatments. Long photoperiods (12 or 14 hours) resulted in longer internodes, longer stems, and more flowers per cyme than short photoperiods (8 or 10 hours), but photoperiod had little effect on flowering time. Treatments to reduce latex coagulant and silver thiosulfate treatments had no significant effect on vase life.

The leaf area of an Australian heathland with reference to seasonal changes and the contribution of individual species

1968 ◽  
Vol 16 (3) ◽  
pp. 579 ◽  
Author(s):  
R Jones
Keyword(s):  
Leaf Area ◽  
Seasonal Changes ◽  
Individual Species ◽  
Seasonal Growth ◽  
Seasonal Fluctuations ◽  
Total Leaf Area ◽  
Area Index ◽  
Total Community ◽  
Community Area ◽  
Community Growth

The leaf area of an Australian heathland was determined on harvested material for a series of monthly harvests over 2 years. The leaf area index (LAI) varied from 1 .8 to 3.2. Seasonal growth flushes accounted for the high values, while leaf fall induced by water stress restored the equilibrium to approximately 2.0. The dominant shrub, Leptospermum myrsinoides, contributed 53.5% of the total leaf area, and this species alone caused the seasonal fluctuations in community area. Only three other species contributed more than 5 % to the total. Community growth was characterized by the behaviour of L. myrsinoides. Detailed analyses of this species showed the need for seasonal measurements to fully describe the LAI of evergreen communities.

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