An architectural analysis of Shepherdia canadensis and Shepherdia argentea (Elaeagnaceae): the architectural models

1990 ◽  
Vol 68 (4) ◽  
pp. 719-725 ◽  
Author(s):  
P. A. Hayes ◽  
T. A. Steeves ◽  
B. R. Neal
Keyword(s):  
Key Words ◽  
Growth Patterns ◽  
Seedling Stage ◽  
Architectural Analysis ◽  
Lateral Buds ◽  
Branching Patterns ◽  
Architectural Models ◽  
Morphology Development ◽  
Shepherdia Canadensis ◽  
Root Buds

The growth patterns of Shepherdia canadensis and S. argentea from seedling stage to adult thicket have been analyzed and compared. In S. canadensis, the seedling axis, originally erect, showed a tendency for early bending towards the horizontal, followed by vertical reorientation of the tip. This was coupled with the basitonic expansion of lateral buds. In contrast, the seedling axis of S. argentea remained erect and branching was predominately acrotonic. As plants of S. canadensis matured, successive branches repeated the seedling pattern, reorienting downward with the tip compensating to remain erect. Basal buds expanded to fill the gap in the canopy and these in turn reoriented downward, repeating the cycle and forming a thicket with the youngest shoots in the centre. Rooting of the horizontal axes was observed and in some cases new thickets could be inititated in this way. In S. argentea, however, shoots remained erect and thicket formation occurred by the expansion of ramets from root buds at the periphery of the thicket. The shoots at the centre were thus the oldest. These features, together with information on branching patterns previously reported, have been used to construct constrasting architectural models for the two species. Key words: Elaeagnaceae, Shepherdia, Buffaloberry, architecture, morphology, development.

An architectural analysis of Shepherdia canadensis and Shepherdia argentea: patterns of shoot development

1989 ◽  
Vol 67 (6) ◽  
pp. 1870-1877 ◽  
Author(s):  
P. A. Hayes ◽  
T. A. Steeves ◽  
B. R. Neal
Keyword(s):  
Seasonal Pattern ◽  
Shoot Development ◽  
Distinct Pattern ◽  
Bud Burst ◽  
Internodal Length ◽  
Architectural Analysis ◽  
Lateral Buds ◽  
Long Shoots ◽  
Short Shoots ◽  
Shepherdia Canadensis

In the context of an architectural analysis, the seasonal pattern of shoot development of Shepherdia canadensis and S. argentea (Elaeagnaceae) was examined. In both species floral bud burst was the first outward manifestation of seasonal activity. Vegetative shoots of S. canadensis expanded 3 – 5 pairs of preformed leaves during a period of 9 – 10 weeks. There was no pattern of internodal length that identified annual increments. In S. argentea, 6 – 18 pairs of leaves expanded during a period of 15 – 17 weeks, the variation being related to the extent of neoformation. There was a distinct pattern of internodal length, with a maximum in midseason, so that annual increments could be recognized subsequently. Lateral buds in S. canadensis expanded only proleptically as either short shoots or long shoots. Most had declining growth rates in the subsequent year and within 5 to 7 years had undergone abscission. In S. argentea. lateral buds expanded both sylleptically and proleptically as short shoots, long shoots, or thorns. The distribution pattern of these lateral types was related to the vigour of parent shoot growth. Some abscission of short shoots was noted. For each species a stochastic flow chart of shoot development was prepared and a computer program incorporating actual data was written that simulated shoot development for up to four generations of growth. Comparison of the two species indicates that S. argentea is more plastic in response to environmental conditions.

Premières données sur l'architecture comparée des systèmes racinaires et caulinaires

1994 ◽  
Vol 72 (7) ◽  
pp. 963-975 ◽  
Author(s):  
Claire Atger ◽  
Claude Edelin
Keyword(s):  
Key Words ◽  
Root System ◽  
Woody Plants ◽  
Functional Organization ◽  
Root Systems ◽  
Architectural Analysis ◽  
Tree Crowns ◽  
Tree Root System ◽  
Whole Plant ◽  
Architectural Patterns

Since 1970, the architectural analysis of woody plants has given much information about structural and functional organization of tree crowns, their development, and reiteration patterns. In this study, we have extended this method to tree root systems. We describe the whole architecture of three species and we compare their root system and crown architectural patterns. Key words: architecture, tree, root system, crown, whole plant.

Nucleotypic influences on chromosome-specific chiasma variation in Crepis capillaris. I. Responses to early colchicine treatment and chromosome doubling

Genome ◽  
1996 ◽  
Vol 39 (6) ◽  
pp. 1078-1085 ◽  
Author(s):  
M. T. Abberton ◽  
R. S. Callow
Keyword(s):  
Key Words ◽  
Chiasma Frequency ◽  
Chromosome Doubling ◽  
Colchicine Treatment ◽  
Seedling Stage ◽  
Published Data ◽  
Crepis Capillaris ◽  
The Mean ◽  
Diploid Level ◽  
Multiplicative Effects

Additive and multiplicative effects of colchicine treatment at the seedling stage and of chromosome doubling on chromosome-specific chiasma frequency at metaphase I have been measured in comparisons between C0 and untreated diploids and between C0 autotetraploids and C0 diploids. Early colchicine treatment increases the frequency of chromosome C univalents to 1.8% but has no similar effect on chromosomes A and D. Colchicine treatment has little net effect on mean chiasma frequency, deducting an average of 0.204 chiasmata per set but otherwise multiplying the mean by a factor of 1.182. These additive and multiplicative effects represent averages of six phenotypes. Chromosome doubling in a tetraploid–diploid chimaera subtracts an average of 0.265 chiasmata per set but otherwise doubles the numbers of chiasmata at the diploid level (× 2.134). Comparison of six diploids and tetraploids reveals modest average additive (+ 1.103) and multiplicative effects (× 1.190). The implications of these findings are discussed in the light of new analyses of previously published data. Key words : chiasmata, Crepis, colchicine, meiosis, polyploidy.

scholarly journals Desarrollo arquitectónico de tres especies de Acacia

2017 ◽  
pp. 7
Author(s):  
Amparo Echeverry-Gómez ◽  
Henricus F.M. Vester
Keyword(s):  
Related Species ◽  
Development Pattern ◽  
Vegetative Development ◽  
Development Patterns ◽  
Legume Trees ◽  
Branching Patterns ◽  
Architectural Model ◽  
Architectural Models ◽  
Do So

Studies about the vegetative development of Legume trees are relatively rare. In order to infer about the evolution of different development patterns a study of taxonomically related species is requiered. We analyzed three species of Acacia (A . collinsii, A. cedilloi and A. dolichoslachya) which according to preliminary observations show branching patterns as defined in the architectural model of Troll or Champagnat in order to answer the question which is the evolutionary relation between these models. We describe the development pattern of these species and found that a combination of architectural models is needed to do so. We found that mixed plagiotropic axes in A. collinsii are relayed by orthotropic axes during development and open a discussion to the evolutionary origen of the mixed axis.

Growth of dormant buds on severed rhizomes of Calamagrostis canadensis

1991 ◽  
Vol 71 (4) ◽  
pp. 1093-1099 ◽  
Author(s):  
R. A. Powelson ◽  
V. J. Lieffers
Keyword(s):  
Key Words ◽  
Apical Dominance ◽  
Carbohydrate Content ◽  
Axillary Buds ◽  
Regeneration Potential ◽  
Bud Development ◽  
Calamagrostis Canadensis ◽  
Lateral Buds ◽  
Loam Soil ◽  
Shoot Base

The regeneration potential and dormancy of lateral buds on rhizome segments near the parent shoot base or the distal rhizome apex of Calamagrostis canadensis were assessed. Apical and basal segments of various length, with and without the parental shoot base or rhizome apex attached, were planted 1 cm deep in loam soil. When the apex or base was attached axillary buds on the rhizome usually remained dormant. When the parental shoot base was excised, the bud closest to the rhizome base was more likely to sprout than more distal buds. When the apex was excised from the apical segments, more axillary buds emerged but no priority of bud development arose. Buds near the apex position generally had a higher frequency of sprouting than buds adjacent to the parental base. Rhizome segments adjacent to the apex were heavier and had a higher nonstructural carbohydrate content than rhizome segments adjacent to the parental base. Key words: Calamagrostis canadensis, rhizome, dormancy, apical dominance, competition

Response of oilseed Brassica cultivars to ozone

1993 ◽  
Vol 73 (4) ◽  
pp. 1077-1078 ◽  
Author(s):  
P. Hucl ◽  
W. D. Beversdorf
Keyword(s):  
Brassica Napus ◽  
Key Words ◽  
Brassica Species ◽  
Seedling Stage ◽  
Foliar Injury

Cultivars of four oilseed Brassica species were exposed to acute levels of ozone (0.31 or 0.47 μL L−1) at the seedling stage. Brassica hitra ’BHL-926’ was the most sensitive to ozone followed by B. juncea ’Newton’ and B. rapa ’Torch.’ Brassica napus seedlings exhibited very little foliar injury (0 – 4%) after 24 h exposure to 0.31 μL L−1 ozone. Key words: Ozone, foliar injury, rapeseed, mustard

Rhamnaceae with multiple lateral buds: an architectural analysis

1992 ◽  
Vol 108 (3) ◽  
pp. 275-286 ◽  
Author(s):  
G. M. TOURN ◽  
R. D. TORTOSA ◽  
D. MEDAN
Keyword(s):  
Architectural Analysis ◽  
Lateral Buds

Plagiotropic architectural development of four tree species of the temperate forest

1998 ◽  
Vol 76 (12) ◽  
pp. 2100-2118 ◽  
Author(s):  
Jeanne Millet ◽  
André Bouchard ◽  
Claude Édelin
Keyword(s):  
Tree Species ◽  
Morphological Differentiation ◽  
Fagus Grandifolia ◽  
Growth Patterns ◽  
Ulmus Americana ◽  
Architectural Analysis ◽  
The Hierarchical Structure ◽  
Temperate Deciduous ◽  
Temperate Deciduous Forests ◽  
Architectural Development

Four tree species of the temperate deciduous forests of south-western Québec have an architectural development that corresponds to Troll's model. Two of these species, American elm (Ulmus americana L.) and American basswood (Tilia americana L.), are mid-successional and the two others, American beech (Fagus grandifolia Ehrh.) and Eastern hemlock (Tsuga canadensis (L.) Carr.), are late successional. In the four species, the main stem is the result of the stacking of modules with plagiotropic development and secondary straightening. Nevertheless, the architectural analysis of these four species reveals that two growth patterns are present. In elm and basswood, the modules are differentiated from one another and are integrated into the hierarchical structure of the tree. In beech and hemlock, the modules are mixed and their apical meristems possess an autodifferentiation potential, which provides for a greater individuality within the tree structure. In spite of belonging to the same architectural model, differences in the development pattern favour a greater efficiency in stem growth for elm and basswood versus a greater shape plasticity, including a greater lateral branch development if required, in beech and hemlock.Key words: tree architecture, organization plan, Troll's model, plagiotropy, morphological differentiation of axes.

scholarly journals Long term pasture growth patterns for Southland New Zealand: 1978 to 2012

2012 ◽  
pp. 147-151
Author(s):  
L.C. Smith
Keyword(s):  
New Zealand ◽  
Key Words ◽  
Growth Rates ◽  
Initial Period ◽  
Farm Management ◽  
Growth Patterns ◽  
Annual Growth ◽  
Management Systems ◽  
Summer Peak

Pasture growth rates for Southland were reported by several researchers in the late 1970s and early 1980s. However, pasture species and farm management systems have changed somewhat since then. This paper presents data from measurements at Woodlands, near Invercargill, that have been ongoing since 1977, and discusses some of the variability that has occurred over the years. Measurement of pasture growth was done using a standardised cutting method known as "rate of growth" or moving cages, with measurements every 3 weeks. Annual yields were calculated from 1 June to 31 May of the next year. The pasture growth at Woodlands is characterised by a spring-summer peak of growth followed by a deep winter trough where growth is minimal. Long-term average annual growth was 11.8 t DM/ha for older 'Ruanui' based pasture and 12.7 t DM/ ha for newer 'Nui'/'Supreme'/'Greenstone' ryegrass based pasture. However the newer pasture produced considerably more (ca.14.2 t DM/ha/year) for an initial period of 3 years, after which time the production dropped back to be similar to the old pasture (ca.12.0 t DM/ha/year). Key words. pasture growth; long-term; annual variability

GROWTH PATTERNS OF RANGE BEEF CALVES OVER DISCRETE PREWEANING INTERVALS

1989 ◽  
Vol 69 (4) ◽  
pp. 865-869 ◽  
Author(s):  
K. M. HAVSTAD ◽  
M. J. McINERNEY ◽  
S. B. CHURCH
Keyword(s):  
Key Words ◽  
Growth Rates ◽  
Seasonal Variations ◽  
Growth Patterns ◽  
Seasonal Growth ◽  
Management Performance ◽  
Beef Calves ◽  
Maximum Interval

Suckling range beef calf production demonstrates periodicity despite consistency of management. Performance of calves within 33- to 50-d intervals from birth to weaning over nine seasons demonstrated maximum interval growth of approximately 1 kg d−1, but average seasonal growth rates varied from 0.79 to 0.99 kg d−1. Maximizing available forages for the final 33 d preweaning could minimize seasonal variations in calf production. Key words: Calf production, liveweight gain, rangelands

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