Growth patterns of the lateral roots of young oak (Quercus robur) tree seedlings Relationship with apical diameter

The objectives of this study were to determine root and shoot growth periodicity for established Fraxinus pennsylvanica Marsh. (green ash), Quercus coccinea Muenchh. (scarlet oak), Corylus colurna L. (Turkish hazelnut), and Syringa reticulata (Blume) Hara `Ivory Silk' (tree lilac) trees and to evaluate three methods of root growth periodicity measurement. Two methods were evaluated using a rhizotron. One method measured the extension rate (RE) ofindividual roots, and the second method measured change in root length (RL) against an observation grid. A third method, using periodic counts of new roots present on minirhizotrons (MR), was also evaluated. RE showed the least variability among individual trees. Shoot growth began before or simultaneously with the beginning of root growth for all species with all root growth measurement methods. All species had concurrent shoot and root growth, and no distinct alternating growth patterns were evident when root growth was measured by RE. Alternating root and shoot growth was evident, however, when root growth was measured by RL and MR. RE measured extension rate of larger diameter lateral roots, RL measured increase in root length of all diameter lateral roots and MR measured new root count of all sizes of lateral and vertical roots. Root growth periodicity patterns differed with the measurement method and the types of roots measured.

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Importance of First-Order Lateral Roots in the Early Development of Forest Tree Seedlings

Interrelationships between Microorganisms and Plants in Soil, Proceedings of an International Symposium Liblice - Developments in Soil Science ◽

10.1016/s0166-2481(08)70210-1 ◽

1989 ◽

pp. 157-169 ◽

Cited By ~ 2

Author(s):

P.P. Kormanik

Keyword(s):

Early Development ◽

Lateral Roots ◽

Forest Tree ◽

Tree Seedlings ◽

First Order

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Modelling time variations of root diameter and elongation rate as related to assimilate supply and demand

Journal of Experimental Botany ◽

10.1093/jxb/eraa122 ◽

2020 ◽

Vol 71 (12) ◽

pp. 3524-3534

Author(s):

Loïc Pagès ◽

Marie Bernert ◽

Guillaume Pagès

Keyword(s):

Root System ◽

Root Elongation ◽

Lateral Roots ◽

Supply And Demand ◽

Root System Architecture ◽

Elongation Rate ◽

Growth Patterns ◽

Root Tip ◽

Generic Model ◽

Maximal Diameter

Abstract In a given root system, individual roots usually exhibit a rather homogeneous tip structure although highly different diameters and growth patterns, and this diversity is of prime importance in the definition of the whole root system architecture and foraging characteristics. In order to represent and predict this diversity, we built a simple and generic model at root tip level combining structural and functional knowledge on root elongation. The tip diameter, reflecting meristem size, is used as a driving variable of elongation. It varies, in response to the fluctuations of photo-assimilate availability, between two limits (minimal and maximal diameter). The elongation rate is assumed to be dependent on the transient value of the diameter. Elongation stops when the tip reaches the minimal diameter. The model could satisfactorily reproduce patterns of root elongation and tip diameter changes observed in various species at different scales. Although continuous, the model could generate divergent root classes as classically observed within populations of lateral roots. This model should help interpret the large plasticity of root elongation patterns which can be obtained in response to different combinations of endogenous and exogenous factors. The parameters could be used in phenotyping the root system.

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Efficient genetic transformation of Impatiens hawkerii Bull. (Balsamiaceae) using agrobacterium rhizogenes

Archives of Biological Sciences ◽

10.2298/abs0903467m ◽

2009 ◽

Vol 61 (3) ◽

pp. 467-474 ◽

Cited By ~ 3

Author(s):

Snezana Milosevic ◽

Angelina Subotic ◽

A. Cingel ◽

Sladjana Jevremovic ◽

Slavica Ninkovic

Keyword(s):

Agrobacterium Rhizogenes ◽

Hairy Root ◽

Hairy Roots ◽

Lateral Roots ◽

Basal Medium ◽

Growth Patterns ◽

Pcr Analysis ◽

Gus Assay ◽

Hairy Root Clones ◽

First Time

Transformation of Impatiens hawkerii Bull. mediated by Agrobacterium rhizogenes strain A4M70GUS was studied. Hairy roots developed 10 days after inoculation were excised from the shoot explants and transferred onto Murashige and Skoog's (MS) basal medium lacking plant growth regulators. More than 20 hairy root clones were established and eight of them were further analyzed. Each clone differed significantly from the others in growth capacity and lateral branching. Clone C2 showed the highest biomass (20.6 g L-1) as well as the highest number of lateral roots (37 ? 2.2). The transgenic nature of the established hairy root clones was confirmed by GUS assay and PCR analysis. In conclusion, hairy roots were developed for the first time in I. hawkerii Bull., and transgenic hairy root clones showed a distinct morphological nature and growth patterns.

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Root mapping of three tropical pasture species using 32P

Australian Journal of Experimental Agriculture ◽

10.1071/ea9690445 ◽

1969 ◽

Vol 9 (39) ◽

pp. 445 ◽

Cited By ~ 2

Author(s):

RA Bray ◽

JB Hacker ◽

DE Byth

Keyword(s):

Root Growth ◽

Root Development ◽

Lateral Root ◽

Sandy Loam ◽

Lateral Roots ◽

Root Systems ◽

Growth Patterns ◽

Constant Rate ◽

Initial Root

Root growth patterns of Glycine javanica, Setaria anceps, and Medicago sativa were studied by uptake of 32P from a sandy loam. Placement of isotope was through permanently positioned PVC conduit on a grid over a 90� quadrant of the root system. Detection of radioactivity was in in situ plant material. Lucerne had strong initial root development but was slow to form lateral roots. Glycine and Setaria had quite similar root systems although Setaria had more rapid vertical root development than Glycine. Both these species had strong lateral root systems. When a regression of minimum root length against time was calculated, lateral root growth was shown to be independent of depth and distance from the plant, suggesting that roots behave as if growing from a point source in random directions at a constant rate. This rate was the same for all species. There were also indications of strong vertical root systems in lucerne and Setaria.

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Decision Making within Plant Root Systems

10.32747/1996.7613030.bard ◽

1996 ◽

Author(s):

Yoav Waisel ◽

Bobbie McMichael ◽

Amram Eshel

Keyword(s):

Root System ◽

System Architecture ◽

Plant Root ◽

Lateral Roots ◽

Root Systems ◽

Root System Architecture ◽

Growth Patterns ◽

Soil Conditions ◽

Stage Of Development ◽

Root Types

Architecture of a root system is the expression of the potential of various root types to branch, to grow and to coordinate with other plant organs, under the specific limitations of the environmental conditions. The present investigation has proven the following points. 1) Genotypes with different types of root systems were identified. The growth patterns of their roots and the distribution of laterals along their main axes were recorded. 2) The patterns of development of the root systems of four cotton genotypes, throughout the entire life cycle of the plants, were described, even at such a late stage of development when the total length of the roots exceeded two kilometers. To the best of our knowledge, this is the first time that an analysis of this type is accomplished. 3) The development of root systems under restrictive soil conditions were compared with those that have developed under the non-restrictive conditions of aeroponics. Results indicate that in the absence of the mechanical impedance of the soil, cotton plants develop single roots that reach the length of 6 m, and have a total root length of 2000 m. Thus, root growth is strongly inhibited by the soil, with some root types being inhibited more than others. 4) One of the important decisions, in constructing an operational root system architecture of mature plants, is the shift of the balance between various root fractions in favor of the very fine roots. 5) Root system architecture is determined, in part, by the sites of initiation of the lateral roots. This is determined genetically by the number of xylem archs and by the totuosity of the stele. Selection for such traits should be sought.

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Phenology of tree seedlings in relation to seed size

Canadian Journal of Botany ◽

10.1139/b91-072 ◽

1991 ◽

Vol 69 (3) ◽

pp. 532-538 ◽

Cited By ~ 56

Author(s):

Kenji Seiwa ◽

Kihachiro Kikuzawa

Keyword(s):

Seed Size ◽

Growth Patterns ◽

Light Limitation ◽

Tree Seedlings ◽

Turnover Rates ◽

Leaf Production ◽

Leaf Emergence ◽

Short Period ◽

Leaf Turnover ◽

Leaf Dynamics

Vertical growth patterns and leaf dynamics of seedlings of 31 deciduous broad-leaved tree species with different seed sizes were examined under either open or shaded conditions. Seed size positively affected initial seedling height and leaf longevity, and negatively affected duration of leaf emergence and leaf-turnover rate. Large-seeded species completed shoot elongation and almost all of their annual leaf production in a short period, irrespective of shading. Small-seeded species attained maximum heights similar to those of large-seeded species under open conditions by having a longer duration of leaf emergence, higher resource allocation to leaf production, and rapid leaf turnover. However, leaf-production and leaf-turnover rates were reduced by shading for small-seeded species, a trait that resulted in lower final seedling heights for small- versus large-seeded species. In small-seeded species, maximum seedling growth was attained only under open conditions through changes in the phenology of leaf dynamics. In contrast, growth of large-seeded species was independent of the effect of light limitation. The importance of seed size in determining seedling establishment success depends on the relationships between seasonal change of environmental light conditions and characteristics of seedling phenology, which are related to seed size. Key words: seed size, tree seedlings, leaf dynamics, phenology, establishment strategies.

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Functional ecology of advance regeneration in relation to light in boreal forests

Canadian Journal of Forest Research ◽

10.1139/x99-070 ◽

1999 ◽

Vol 29 (6) ◽

pp. 812-823 ◽

Cited By ~ 202

Author(s):

Christian Messier ◽

René Doucet ◽

Jean-Claude Ruel ◽

Yves Claveau ◽

Colin Kelly ◽

...

Keyword(s):

Boreal Forests ◽

Light Availability ◽

Growth Patterns ◽

Functional Ecology ◽

Tree Seedlings ◽

Maximum Height ◽

Surface Area Ratio ◽

Growth And Survival ◽

Advance Regeneration ◽

Leaf Level

This paper reviews aspects of the functional ecology of naturally established tree seedlings in the boreal forests of North America with an emphasis on the relationship between light availability and the growth and survival of shade tolerant conifers up to pole size. Shade tolerant conifer species such as firs and spruces tend to have a lower specific leaf mass, photosynthetic rate at saturation, live crown ratio, STAR (shoot silhouette area to total needle surface area ratio), and root to shoot ratio than the shade intolerant pines. The inability of intolerant species such as the pines and aspen to survive in shade appears to be mainly the result of characteristics at the shoot, crown, and whole-tree levels and not at the leaf level. Although firs and spruces frequently coexist in shaded understories, they do not have identical growth patterns and crown architectures. We propose a simple framework based on the maximum height that different tree species can sustain in shade, which may help managers determine the timing of partial or complete harvests. Consideration of these functional aspects of regeneration is important to the understanding of boreal forest dynamics and can be useful to forest managers seeking to develop or assess novel silvicultural systems.

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Differential radial growth patterns between beech (Fagus sylvatica L.) and oak (Quercus robur L.) on periodically waterlogged soils

Tree Physiology ◽

10.1093/treephys/tpt020 ◽

2013 ◽

Vol 33 (4) ◽

pp. 425-437 ◽

Cited By ~ 23

Author(s):

T. Scharnweber ◽

M. Manthey ◽

M. Wilmking

Keyword(s):

Fagus Sylvatica ◽

Radial Growth ◽

Quercus Robur ◽

Growth Patterns ◽

Fagus Sylvatica L ◽

Waterlogged Soils

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Differential growth of individual components of trees and their interrelationships

Canadian Journal of Forest Research ◽

10.1139/x86-060 ◽

1986 ◽

Vol 16 (2) ◽

pp. 352-359 ◽

Cited By ~ 2

Author(s):

S. Eis

Keyword(s):

Lateral Roots ◽

Growth Patterns ◽

Differential Growth ◽

Average Decrease ◽

Diameter Increment ◽

Red Cedar ◽

Forest Sites ◽

Length Increment ◽

Structural Roots ◽

One Year

The growth of six Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco), eight western hemlock (Tsugaheterophylla (Raf.) Sarg.), and eight western red cedar (Thujaplicata Donn.) trees was studied using standard stem-analysis techniques. Trees standing side by side had similar height and diameter increment patterns, i.e., high and low increments in identical years. With increasing distance, this similarity rapidly decreased even on identical forest sites. On different sites, the patterns were different, often opposite. The length increment pattern on branches was similar to that shown by stem height increment only on four to five top whorls. On exposed branches the average decrease of both diameter and length increments was slow and fluctuated widely from one year to another. On shaded branches the decrease in increment was rapid and smooth. Growth of roots was very irregular and uncorrelated one with another; while some grew rapidly in length in some years, others in the same root system grew slowly or not at all. The radial increments and the increment patterns of structural roots were similar to the pattern in the stem, but long, ropelike lateral roots had their own independent growth patterns dissimilar to those of any other part of the tree.

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