Factors affecting the distribution of proteoid roots within the root systems of two Hakea species

1973 ◽  
Vol 21 (2) ◽  
pp. 165 ◽  
Author(s):  
B Lamont
Keyword(s):  
Organic Matter ◽  
Root System ◽  
Root Systems ◽  
Physical Factors ◽  
Root Weight ◽  
Local Concentration ◽  
Horizontal Distance ◽  
Proteoid Roots ◽  
Local Soil ◽  
Proteoid Root

The proteoid roots of Hakea prostrata and H. laurina are concentrated in the surface soil horizons, even though the root systems penetrate to much greater depths. The relationships of a number of soil and plant factors to proteoid root occurrence in a given portion of the root system were examined. Pockets of humus-rich soil in any part of the root system greatly increased the proteoid root concentration in that region. The following factors, listed in their apparent order of importance, were analysed: local concentration of parent roots, local level of soil organic matter, local nitrogen availability, shoot growth, nitrogen concentration of the shoots, vertical distance of the region from the soil surface, local availability of calcium, magnesium, and potassium, local bulk density and certain other physical factors, nutrient status of the rest of the root system, horizontal distance of the region from the centre of the plant, relative maturity of parent roots in the region, and local soil pH and certain other chemical factors. The nitrogen component of soil regions high in organic matter largely accounted for their higher non-proteoid root concentration, smaller proteoid root size, greater number of laterals, and longer roots per unit weight, but not their much greater number of proteoid roots per unit total root weight. This suggests that other factors are also involved in proteoid root formation.

The Effects of Seasonality and Waterlogging on the Root Systems of a Number of Hakea Species

1976 ◽  
Vol 24 (6) ◽  
pp. 691 ◽  
Author(s):  
B Lamont
Keyword(s):  
Redox Potential ◽  
Root System ◽  
Water Availability ◽  
Field Capacity ◽  
Climatic Conditions ◽  
Root Weight ◽  
Proteoid Roots ◽  
Growth Increase ◽  
Steep Decline ◽  
Proteoid Root

Proteoid and non-proteoid roots are produced only during winter-spring under the Mediterranean climatic conditions of south-western Australia. However, dormant roots can be induced to form new root structures in summer, if sufficient water is applied to that part of the root system. The seasonal occurrence of proteoid roots is therefore due to the annual variation in water available for growth of the surface parent roots. Both proteoid and non-proteoid root growth increase as water availability is increased from the permanent wilting point to one to two times field capacity, with a trebling in the proportion of proteoid roots by weight in the root system. This is followed by a steep decline in total root weight and in the proportion of proteoid roots in the root system as water availability is increased from two to three times field capacity. While the size of proteoid roots is greatest under non-waterlogged conditions (redox potential of 450-550 mV), their number per unit total root weight is greatest under moderately waterlogged conditions (redox potential of 120-350 mV).

Distribution and density of the root system of macadamia on krasnozem soil and some effects of legume groundcovers on fibrous root density

2003 ◽  
Vol 43 (5) ◽  
pp. 503 ◽  
Author(s):  
D. J. Firth ◽  
R. D. B. Whalley ◽  
G. G. Johns
Keyword(s):  
Root System ◽  
Root Length ◽  
Root Length Density ◽  
Root Systems ◽  
Soil Cores ◽  
Fibrous Root ◽  
Proteoid Roots ◽  
Dry Conditions ◽  
Proteoid Root ◽  
Fibrous Roots

Whole-tree excavations, root-core and minirhizotron studies indicate that the grafted macadamia tree root system is relatively shallow and spreading, with a short taproot and most of the fibrous root system near the soil surface, while ungrafted trees have a longer taproot. The length of fibrous roots diminished with depth and distance from the trunk. This pattern is consistent with other fruit trees, in that the highest density is generally within 1 m of the trunk. Values obtained in core samples in this study were 4.97 (± 0.43) cm/cm3 and 1.67 (± 0.45) cm/cm3 for 0–10 cm and 10–20 cm at 0.5 m from the trunk, and 2.34 and 1.08 cm/cm3, respectively, at 1 m from the trunk at Clunes. These values were similar to those obtained in separate studies in 1991–93, involving assessments at 5�cm depth increments down to 15 cm, where mean root length densities were 2.0–3.5 cm/cm3 and 1.3–1.9 cm/cm3 at 0–5 cm and 5–15 cm depth, respectively, 1.4 m from the trunk. Root length under old trees in bare soil at Dorroughby and Clunes, using minirhizotrons (0.25–0.40 cm/cm2) and soil cores (1.14 and 3.50 cm/cm3, respectively), was similar to that found at other sites in the study area (minirhizotrons 0.28–0.33 cm/cm2; soil cores 1.25–2.80 cm/cm3). There is an apparent lower rate of decrease in root length density with increasing distance from the trunk at 10–20 cm compared with 0–10 cm. New root growth occurred predominantly in autumn, but some new fibrous roots were produced in early winter and spring. Proteoid roots were found in abundance in soil cores and adjacent to minirhizotron tubes and there were more of them in the root systems of younger trees at Clunes than with older trees at Dorroughby. Proteoid roots were found at a greater depth than previously recorded for other Proteaceae species, and appeared to retain their function in relatively dry conditions for more than a year. Non-proteoid fibrous roots at the minirhizotron surface appeared to be functional for about 1.5 years in relatively dry conditions, before decay after the onset of wet soil conditions.The effects of 2 newly established perennial legume groundcovers on the root systems of younger and older macadamia trees were studied over 2.5 years. In general, the presence of groundcover either had no effect on the growth of the macadamia roots or increased the root length density at some sampling dates and some depths. At Clunes, where the proteoid root length density was higher than at Dorroughby, the presence of groundcover was associated with higher proteoid root length density than that with bare ground. Arachis pintoi cv. Amarillo generally had a lower root length density than Lotus pedunculatus.

The morphology and anatomy of proteoid roots in the genus Hakea

1972 ◽  
Vol 20 (2) ◽  
pp. 155 ◽  
Author(s):  
B Lamont
Keyword(s):  
Special Reference ◽  
Root System ◽  
Plant Age ◽  
Proteoid Roots ◽  
Relative Contribution ◽  
Endophytic Microorganisms ◽  
As Species ◽  
The Family ◽  
Proteoid Root

This paper extends the introductory work of Purnell(1960) on proteoid roots in the family Proteaceae by a detailed study of the genus Hakea, with special reference to H. prostrata. The presence of proteoid roots is reported in 63 Hakea species. Their relative contribution to the root system is related to such plant factors as species, age, and cotyledon size. The dimensions of proteoid roots are dependent on plant age and species. The morphology and anatomy of these structures are described. Endophytic microorganisms are not normally associated with proteoid roots. Proteoid rootlets survive 2-3 months, though their parent roots last indefinitely. Proteoid roots are produced by the youngest roots in the root system. While proteoid rootlets arise laterally, the parent root may arise either laterally or adventitiously. Both proteoid and non-proteoid roots may be initiated within a proteoid root.

scholarly journals Clifford Spinors and Root System Induction: $$H_4$$ and the Grand Antiprism

2021 ◽  
Vol 31 (3) ◽  
Author(s):  
Pierre-Philippe Dechant
Keyword(s):  
Root System ◽  
Root Systems ◽  
Invariant Sets ◽  
Simple Construction ◽  
Reflection Groups ◽  
Computational Work ◽  
Algebraic Framework ◽  
Underlying Geometry ◽  
Coxeter Plane ◽  
Insight Into

AbstractRecent work has shown that every 3D root system allows the construction of a corresponding 4D root system via an ‘induction theorem’. In this paper, we look at the icosahedral case of $$H_3\rightarrow H_4$$ H 3 → H 4 in detail and perform the calculations explicitly. Clifford algebra is used to perform group theoretic calculations based on the versor theorem and the Cartan–Dieudonné theorem, giving a simple construction of the $${\mathrm {Pin}}$$ Pin and $${\mathrm {Spin}}$$ Spin covers. Using this connection with $$H_3$$ H 3 via the induction theorem sheds light on geometric aspects of the $$H_4$$ H 4 root system (the 600-cell) as well as other related polytopes and their symmetries, such as the famous Grand Antiprism and the snub 24-cell. The uniform construction of root systems from 3D and the uniform procedure of splitting root systems with respect to subrootsystems into separate invariant sets allows further systematic insight into the underlying geometry. All calculations are performed in the even subalgebra of $${\mathrm {Cl}}(3)$$ Cl ( 3 ) , including the construction of the Coxeter plane, which is used for visualising the complementary pairs of invariant polytopes, and are shared as supplementary computational work sheets. This approach therefore constitutes a more systematic and general way of performing calculations concerning groups, in particular reflection groups and root systems, in a Clifford algebraic framework.

On Closed Subsets of Root Systems

1994 ◽  
Vol 37 (3) ◽  
pp. 338-345 ◽  
Author(s):  
D. Ž. Doković ◽  
P. Check ◽  
J.-Y. Hée
Keyword(s):  
Weyl Group ◽  
Root System ◽  
Irreducible Component ◽  
Product Space ◽  
Root Systems ◽  
Inner Product Space ◽  
Inner Product ◽  
Closed Sets ◽  
Finite Dimensional ◽  
Real Inner Product Space

AbstractLet R be a root system (in the sense of Bourbaki) in a finite dimensional real inner product space V. A subset P ⊂ R is closed if α, β ∊ P and α + β ∊ R imply that α + β ∊ P. In this paper we shall classify, up to conjugacy by the Weyl group W of R, all closed sets P ⊂ R such that R\P is also closed. We also show that if θ:R —> R′ is a bijection between two root systems such that both θ and θ-1 preserve closed sets, and if R has at most one irreducible component of type A1, then θ is an isomorphism of root systems.

scholarly journals Morphological Characterization of Root System Architecture in Diverse Tomato Genotypes during Early Growth

2018 ◽  
Vol 19 (12) ◽  
pp. 3888 ◽  
Author(s):  
Aurora Alaguero-Cordovilla ◽  
Francisco Gran-Gómez ◽  
Sergio Tormos-Moltó ◽  
José Pérez-Pérez
Keyword(s):  
Root System ◽  
System Architecture ◽  
Lateral Root ◽  
Morphological Plasticity ◽  
Root System Architecture ◽  
Morphological Characterization ◽  
Early Growth ◽  
Soil Conditions ◽  
Wild Tomato Species ◽  
Local Soil

Plant roots exploit morphological plasticity to adapt and respond to different soil environments. We characterized the root system architecture of nine wild tomato species and four cultivated tomato (Solanum lycopersicum L.) varieties during early growth in a controlled environment. Additionally, the root system architecture of six near-isogenic lines from the tomato ‘Micro-Tom’ mutant collection was also studied. These lines were affected in key genes of ethylene, abscisic acid, and anthocyanin pathways. We found extensive differences between the studied lines for a number of meaningful morphological traits, such as lateral root distribution, lateral root length or adventitious root development, which might represent adaptations to local soil conditions during speciation and subsequent domestication. Taken together, our results provide a general quantitative framework for comparing root system architecture in tomato seedlings and other related species.

Extension and Longitudinal Growth During the Development of Red Pine Root Systems

1975 ◽  
Vol 5 (1) ◽  
pp. 109-121 ◽  
Author(s):  
D. C. F. Fayle
Keyword(s):  
Root System ◽  
Root Systems ◽  
Red Pine ◽  
Longitudinal Growth ◽  
Rooting Depth ◽  
Soil Conditions ◽  
Moisture Availability ◽  
Below Ground

Extension of the root system and stem during the first 30 years of growth of plantation-grown red pine (Pinusresinosa Ait.) on four sites was deduced by root and stem analyses. Maximum rooting depth was reached in the first decade and maximum horizontal extension of roots was virtually complete between years 15 and 20. The main horizontal roots of red pine seldom exceed 11 m in length. Elongation of vertical and horizontal roots was examined in relation to moisture availability and some physical soil conditions. The changing relations within the tree in lineal dimensions and annual elongation of the roots and stem are illustrated. The development of intertree competition above and below ground is considered.

Effects of Temperature on Root Morphology and Ectendomycorrhizal Development in Pinusresinosa Ait.

1975 ◽  
Vol 5 (2) ◽  
pp. 171-175 ◽  
Author(s):  
Hugh E. Wilcox ◽  
Ruth Ganmore-Neumann
Keyword(s):  
Root Growth ◽  
Root System ◽  
Root Morphology ◽  
Root Systems ◽  
Second Order ◽  
Root Temperature ◽  
First Order ◽  
Effects Of Temperature

Seedlings of Pinusresinosa were grown at root temperatures of 16, 21 and 27 °C, both aseptically and after inoculation with the ectendomycorrhizal fungus BDG-58. Growth after 3 months was significantly influenced by the presence of the fungus at all 3 temperatures. The influence of the fungus on root growth was obscured by the effects of root temperature on morphology. The root system at 16 and at 21 °C possessed many first-order laterals with numerous, well developed second-order branches, but those at 27 °C had only a few, relatively long, unbranched first-order laterals. Although the root systems of infected seedlings were larger, the fungus increased root growth in the same pattern as determined by the temperature.

scholarly journals Contemporary Concepts of Root System Architecture of Urban Trees

2010 ◽  
Vol 36 (4) ◽  
pp. 149-159
Author(s):  
Susan Day ◽  
P. Eric Wiseman ◽  
Sarah Dickinson ◽  
J. Roger Harris
Keyword(s):  
Built Environment ◽  
Root Growth ◽  
Root System ◽  
Root Architecture ◽  
Root Systems ◽  
Growth Patterns ◽  
Urban Trees ◽  
Rooting Depth ◽  
Similar Species ◽  
Urban Settings

Knowledge of the extent and distribution of tree root systems is essential for managing trees in the built environment. Despite recent advances in root detection tools, published research on tree root architecture in urban settings has been limited and only partially synthesized. Root growth patterns of urban trees may differ considerably from similar species in forested or agricultural environments. This paper reviews literature documenting tree root growth in urban settings as well as literature addressing root architecture in nonurban settings that may contribute to present understanding of tree roots in built environments. Although tree species may have the genetic potential for generating deep root systems (>2 m), rooting depth in urban situations is frequently restricted by impenetrable or inhospitable soil layers or by underground infrastructure. Lateral root extent is likewise subject to restriction by dense soils under hardscape or by absence of irrigation in dry areas. By combining results of numerous studies, the authors of this paper estimated the radius of an unrestricted root system initially increases at a rate of approximately 38 to 1, compared to trunk diameter; however, this ratio likely considerably declines as trees mature. Roots are often irregularly distributed around the tree and may be influenced by cardinal direction, terrain, tree lean, or obstacles in the built environment. Buttress roots, tap roots, and other root types are also discussed.

scholarly journals EFFECT OF IRRIGATION ON ROOT DEVELOPMENT OF COFFEE PLANTS

Irriga ◽  
2019 ◽  
Vol 24 (2) ◽  
pp. 378-391
Author(s):  
Marcelo Rossi Vicente ◽  
Everardo Chartuni Mantovani ◽  
André Luís Teixeira Fernandes ◽  
Júlio Cesar Lima Neves ◽  
Edmilson Marques Figueredo ◽  
...  
Keyword(s):  
Root System ◽  
Root Development ◽  
Coffea Arabica ◽  
Crop Yields ◽  
Root Length Density ◽  
Block Design ◽  
Minas Gerais ◽  
Root Weight ◽  
Coffee Plants ◽  
Coffea Arabica L

EFFECT OF IRRIGATION ON ROOT DEVELOPMENT OF COFFEE PLANTS     MARCELO ROSSI VICENTE1; EVERARDO CHARTUNI MANTOVANI2; ANDRÉ LUÍS TEIXEIRA FERNANDES3; JÚLIO CÉSAR LIMA NEVES4; EDMILSON MARQUES FIGUEREDO5 E FÁBIO TEIXEIRA DELAZARI6   1 Instituto Federal do Norte de Minas Gerais, Campus Salinas, Fazenda Varginha, Rodovia Salinas – Taiobeiras, Km 2, 39560-00, Salinas, Minas Gerais, Brasil, [email protected] 2 Departamento de Engenharia Agrícola e Ambiental, Universidade Federal de Viçosa, Campus Universitário, Viçosa, 36570.900, Minas Gerais, Brasil, [email protected] 3 Universidade de Uberaba, Av. Nenê Sabino, n° 1801, 38055-500, Uberaba, Minas Gerais, Brasil, [email protected] 4 Departamento de Solos, Universidade Federal de Viçosa, Campus Universitário, Viçosa, 36570-900, Minas Gerais, Brasil, [email protected] 5 Bahia Farm Show, Av. Ahylon Macedo, n° 919, 97810-035, Barreiras, Bahia, Brasil, [email protected] 6 Departamento de Fitotecnia, Universidade Federal de Viçosa, Campus Universitário, Viçosa, 36570-900, Minas Gerais, Brasil, [email protected]     1 ABSTRACT   Increasing the development and deepening of the root system in coffee crops ensures higher water and nutrient uptakes as a result of improved soil utilization, ultimately leading to greater crop yields and longevity. The aim of this study was to evaluate the effect of irrigation levels on the root system of drip-irrigated coffee plants in western Bahia State (BA), Brazil. The experiment was carried out on Café do Rio Branco farm, located in Barreiras - BA, using adult plants (approximately 3.5 years old) of coffee variety Catuaí Vermelho IAC 144. The experiment was set up as a randomized block design with three treatments corresponding to the irrigation depths of 75, 100 and 150% as determined using Irriplus software. After the fourth harvest, the coffee root system was assessed to determine root length density (RLD) and root weight density (RWD) in different sampled layers. A greater concentration of roots (RLD and RWD) was observed in the surface layer (0-20 cm) and under the lateral line (at 30 and 70 cm from the orthotropic branch). The irrigation depth of 75% provided the highest concentration of roots (RLD and RWD) in the 0-10 cm layer.   Keywords: Drip irrigation, Coffea arabica L, root system.     VICENTE, M.R.; MANTOVANI, E.C.; FERNANDES, A.L.T.; NEVES, J.C.L.; FIGUEREDO, E.M.; DELAZARI, F.T EFEITO DA IRRIGAÇÃO NO DESENVOLVIMENTO RADICULAR DO CAFEEIRO     2 RESUMO   Um maior desenvolvimento e aprofundamento do sistema radicular garante ao cafezal um aumento da absorção de água e nutrientes devido a maior exploração do solo, com isto maior produtividade e longevidade da lavoura. O objetivo deste trabalho foi avaliar os efeitos de diferentes lâminas de irrigação sobre o sistema radicular do cafeeiro irrigado por gotejamento na região Oeste da Bahia. Realizou-se o trabalho na fazenda Café do Rio Branco, localizada em Barreiras - BA em cafeeiros adultos, aproximadamente 3,5 anos de idade, da variedade Catuaí Vermelho IAC 144. O experimento ocorreu no delineamento em blocos casualizados, composto de 3 tratamentos, correspondentes à 75, 100 e 150% da lâmina de irrigação determinada pelo software Irriplus. Após a quarta safra, procedeu-se às avaliações do sistema radicular do cafeeiro, onde foi determinada a densidade de comprimento radicular - DCR e a densidade radicular – DR em diferentes camadas amostradas. Observou-se maior concentração de raízes, DCR e DR, na camada superficial (0-20 cm) e sob a linha lateral (30 e 70 cm de distância do ramo ortotrópico). A lâmina de irrigação correspondente a 75% proporcionou maior concentração de raízes (DCR e DR) na camada de 0 a 10 cm.   Palavras - chaves: Irrigação localizada, Coffea arábica L, sistema radicular

Sign in / Sign up

Export Citation Format

Share Document