THE ROOT SYSTEM OF LINARIA VULGARIS MILL.: I. MORPHOLOGY AND ANATOMY

1966 ◽  
Vol 44 (9) ◽  
pp. 1111-1116 ◽  
Author(s):  
W. A. Charlton

The morphology and anatomy of the root system of Linaria vulgaris is described. The invasive behavior of the plant is related to the growth habit of the root system and to the formation of buds on the roots. The root system is described in terms of a framework of vigorous long roots, each passing through a phase of horizontal growth followed by a phase of vertical growth. Long roots bear lateral roots which mostly appear to be of restricted growth; long roots of the next order are generally initiated in the region where the direction of growth of the parent long root changed. Any lateral root is thought to be potentially capable of developing as a long root. There are no qualitative grounds for a separation of long and short roots, though most roots are restricted in their growth. Bud initiation is a feature only of roots which have developed as long roots. Root buds are not formed from the long root tissues, but from the bases of some of the lateral roots of the long roots, always in regions where the parent long root passed over from horizontal to vertical growth, and occasionally on the horizontal parts of long roots. Bud formation has only been found to occur when some secondary growth is present in the parent long root.

1967 ◽  
Vol 45 (1) ◽  
pp. 81-91 ◽  
Author(s):  
W. A. Charlton

The relationship has been investigated between stelar diameter, complexity, and the presence or absence of secondary growth in roots of Linaria vulgaris. Diameter and complexity of the primary xylem body were used as parameters. The presence of secondary growth is considered to be a character of roots developing as long roots. The long roots are responsible for the vegetative propagation of the plant. The frequency of occurrence of secondary growth tends to increase both with stelar diameter and complexity, but secondary growth can occur in roots of any size and complexity. Any root appears to be capable of developing as a long root but the larger roots have a greater chance of so doing. It is thought that roots which are developing as long roots inhibit other roots from such development; probably the larger root apices in any given plant are more capable of escaping from or exerting such inhibition.


2020 ◽  
Vol 36 (1) ◽  
pp. 36-43
Author(s):  
I.O. Konovalova ◽  
T.N. Kudelina ◽  
S.O. Smolyanina ◽  
A.I. Lilienberg ◽  
T.N. Bibikova

A new technique for Arabidopsis thaliana cultivation has been proposed that combines the use of a phytogel-based nutrient medium and a hydrophilic membrane of hydrate cellulose film, separating the root system of the plant from the medium thickness. Growth rates of both main and lateral roots were faster in the plants cultivated on the surface of hydrate cellulose film than in the plants grown in the phytogel volume. The location of the root system on the surface of the transparent hydrate film simplifies its observation and analysis and facilitates plant transplantation with preservation of the root system configuration. The proposed technique allowed us to first assess the effect of exogenous auxin on the growth of lateral roots at the 5-6 developmental stage. methods to study plant root systems, hydrate cellulose film, A. thaliana, lateral roots, differential root growth rate, auxin The work was financially supported by the Russian Foundation for Basic Research (Project Bel_mol_a 19-54-04015) and the basic topic of the Russian Academy of Sciences - IBMP RAS «Regularities of the Influence of Extreme Environmental Factors on the Processes of Cultivation of Higher Plants and the Development of Japanese Quail Tissues at Different Stages of its Ontogenesis under the Conditions of Regenerative Life Support Systems».


2021 ◽  
Author(s):  
Pierre-Mathieu Pélissier ◽  
Hans Motte ◽  
Tom Beeckman

Abstract Lateral roots are important to forage for nutrients due to their ability to increase the uptake area of a root system. Hence, it comes as no surprise that lateral root formation is affected by nutrients or nutrient starvation, and as such contributes to the root system plasticity. Understanding the molecular mechanisms regulating root adaptation dynamics towards nutrient availability is useful to optimize plant nutrient use efficiency. There is at present a profound, though still evolving, knowledge on lateral root pathways. Here, we aimed to review the intersection with nutrient signaling pathways to give an update on the regulation of lateral root development by nutrients, with a particular focus on nitrogen. Remarkably, it is for most nutrients not clear how lateral root formation is controlled. Only for nitrogen, one of the most dominant nutrients in the control of lateral root formation, the crosstalk with multiple key signals determining lateral root development is clearly shown. In this update, we first present a general overview of the current knowledge of how nutrients affect lateral root formation, followed by a deeper discussion on how nitrogen signaling pathways act on different lateral root-mediating mechanisms for which multiple recent studies yield insights.


2014 ◽  
Vol 66 (1) ◽  
pp. 3-15
Author(s):  
Sylwia Ciaglo-Androsiuk

AbstractRelation between morphological traits of the root system and yield related traits is an important issue concerning efforts aiming at improving of ideotype of cultivated plants species, including pea. In this paper, to analyse the dependency between traits describing the root system morphology and yield potential, Person’s andSpearman's_correlations as well as canonical correlations were used.Root system was analyzed in 14 and 21 day-old seedlings growing in blotting-paper cylinders. Yield potential of pea was analysed in a field experiment. Results of Person’s and Spearman's_correlations revealed that number of lateral roots and lateral roots density were correlated witch yield related traits. Correlation between root length and shoot length was observed only for 14 day-old seedlings. The result of canonical correlations revealed that number of lateral roots and lateral roots density had the largest effect on yield related traits. This work highlights, that in order to improve the yield of pea it might become necessary to understand genetic determination of morphological traits of the root system, especially number of lateral roots.


2019 ◽  
Vol 9 (3) ◽  
pp. 151-159
Author(s):  
Magdalena Sunarti Pareira ◽  
Irdika Mansur ◽  
Dewi Wulandari

The sandalwood tree (Santalum album Linn.) is an important tree species as well as a primadonna for the people of East Nusa Tenggara (NTT). It has high economic value for its aromatic wood and essential oil content that have a very distinctive aroma used to make various products such as handicrafts, woodcarvings, incense, and oil for the perfume and cosmetics industry. Sandalwood is a semi parasite plant that part of its life phase requires a host plant to get the nutrients and water. There are many types of host plants that have been used, among others, Casuarina equisetifolia, Acacia mangium, Terminalia microcarpa, Sesbania grandiflora, Alternanthera sp and Capsicum annum. In this research will be tested to try sandalwood planted with Cymbopogon nardus host plants, in terms of economics can provide benefits.Arbuscular mycorrhizal fungi (AMF) is a group of fungi from glomeromycota phylum that can symbiosis mutualism with root system of high level plant. The working principle of the mycorrhiza is to infect the root system of the host plant, producing intensive hyphae tissue so that the plant containing mycorrhiza will be able to increase the capacity in nutrient uptake. The utilization of host plants Alternanthera sp, Capsicum annum, and its application with AMF is the best solution to overcome the problem of developing sandalwood in TTU on the nursery. The purpose of this study was to analyze the effectiveness of AMF and utilization of the atsiri host plant to increase the growth of sandalwood seedlings in TTU. This study was designed using a complete random method (RAL) in split plot design. If the treatment has a significant effect then followed by Duncan Multiple Range Test (DMRT). Parameters observed were height (cm), number of leaf, diameter of sandalwood (mm), dry weight of root, seed quality index, ratio of root buds, and haustorium observation of Sandalwood, and also number of spore, root colonization and AMF dependency of Sandalwood.The results showed that the treatment of AMF with Capsicum annum host plant was 19.8 of high, number of leaf 18.9 on FMA treatment with host plant Capsicum annum, diameter of stem 2.24 mm on Alternanthera sp host treatments without AMF and 1.83 mm at AMF treatment with host plant Capsicum annum, dry weight of buds 2.00g on AMF treatment with Capsicum annum host plant, dry weight of roots AMF (M1) with alternanthera sp 0.70 g, root buds ratio of AMF with host plant alternanthera sp 4.05, seed quality index AMF with Alternanthera sp 4.16 and 82 % of root colonization on AMF with host plant Capsicum annum.Keywords: Santalum album Linn., AMF, host plant.


Author(s):  
Marek Šírl ◽  
Tereza Šnajdrová ◽  
Dolores Gutiérrez-Alanís ◽  
Joseph G. Dubrovsky ◽  
Jean Phillipe Vielle-Calzada ◽  
...  

The AT-HOOK MOTIF NUCLEAR LOCALIZED PROTEIN (AHL) gene family encodes embryophyte-specific nuclear proteins with DNA binding activity. They modulate gene expression and affect various developmental processes in plants. We identify AHL18 (At3G60870) as a developmental modulator of root system architecture and growth. AHL18 regulates the length of the proliferation domain and number of dividing cells in the root apical meristem and thereby, cell production. Both primary root growth and lateral root development respond according to AHL18 transcription level. The ahl18 knock-out plants show reduced root systems due to a shorter primary root and a lower number of lateral roots. This change results from a higher number of arrested and non-developing lateral root primordia (LRP) rather than from decreased initiation. Overexpression of AHL18 results in a more extensive root system, longer primary roots, and increased density of lateral root initiation events. Formation of lateral roots is affected during the initiation of LRP and later development. AHL18 regulate root apical meristem activity, lateral root initiation and emergence, which is in accord with localization of its expression.


2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
ZiFan Sui ◽  
Weijia Yuan ◽  
Wen Yi ◽  
Weihuan Yang

To explore the effect of grass and shrub plant roots on the stability of soil slopes in rainy areas in the south, this article relies on the Longlang Expressway construction project. Cynodon dactylon and Magnolia multiflora were selected as research subjects. The plant distribution characteristics and mechanical properties are analyzed. This paper uses ABAQUS finite element software to construct a 3D model of the planted slope in the test section. The stress and strain on the root system and the soil were observed, and the variation law of slope stability before and after plant protection under different rainfall events was compared and analyzed. The test and simulation results show that the root content of Cynodon dactylon gradually decreases with increasing depth. Cynodon dactylon was mainly distributed in the 0–30 cm soil body, and its effect on improving the cohesion of the soil body reached 75%. Magnolia multiflora belongs to vertical roots and has a strong and longer main root with relatively developed lateral roots. Its root system passes through the sliding surface of the slope bottom, which reduces the maximum equivalent plastic stress generated inside the slope by 61%. When the total rainfall duration is unchanged, under the three rainfall intensities of small, medium, and large, herbaceous plants increase the safety factor of the soil by 1.33%, 2.08%, and 6.1%, respectively, and the roots of shrubs increase the safety factor of the soil by 3.29%, 4.08%, and 4.32%, respectively. When the rainfall intensity does not change, as the rainfall time increases, the effect of plants on the slope safety factor first gradually increases and eventually stabilizes. The research results provide a reliable theoretical basis for analyzing the effect of plant roots on soil consolidation and slope protection, and they also lay a technical foundation for the promotion and application of ecological slope protection technology.


1963 ◽  
Vol 41 (5) ◽  
pp. 579-589 ◽  
Author(s):  
M. V. S. Raju ◽  
T. A. Steeves ◽  
R. T. Coupland

The significance of Euphorbia esula L. as a weed is related to its capacity to persist under adverse conditions and to its mode of reproduction. In both these properties, the root system plays an important role. The root system is initially established by seedlings. The seedling has a vigorous primary root with extensive longitudinal growth and considerable cambial activity. Such a root has been designated a "long" root. By contrast, the first lateral roots produced on the primary root have limited growth and no cambial activity. These roots have been termed "short" roots. Thus, the seedling exhibits a "heterorhizic" pattern. Lateral long roots also arise on the primary root of seedlings but their origin is delayed until cambial activity has begun. Such lateral long roots arise much earlier on seedlings growing in denuded areas than on those growing in areas covered by dense vegetation. The mature root system is described in terms of horizontal and vertical long roots, which make up the conspicuous framework of the system, and of the short roots which they produce. Long roots produce shoot-buds and the origin of these structures is delayed until cambial activity has started. Short roots do not give rise to shoot-buds. Cambial activity in long roots appears to be connected with bud production and its absence in short roots probably underlies their inability to produce buds.L'importance de Euphorbia esula L. comme mauvaise herbe est connexé a son capacité de persister dans les situations hostiles et à sa methode de reproduction. Dans ces deux caractéristiques, le système des racines a une signification profunde. Initialement le système des racines s'établit dans le semis. Le semis a une racine primaire très forte avec beaucoup de croissance longitudinale et avec une activité considérable du cambium. Une racine de cette espèce s'appelle une "longue" racine (long root). Par contre, les premières racines latérales que poussent sur la racine primaire ont croissance limité et aucun activité du cambium. Ces racines s'appellent les "courtes" racines (short roots). De cette façon, le semis montre un dessin "heterorhizique" (heterorhizic). Les longues racines latérales ont aussi leur origine sur la racine primaire du semis, mais l'origine est retardé jusqu'au commencement de l'activité du cambium. Les racines de cette espèce apparaissent beaucoup plus tôt sur les semis qui sont situés en terre sans autre végétation, que sur ceux qui sont situés au milieu des autres plantes. Le système adulte des racines se décrit sous forme des longues racines de l'espèce horizontale et verticale, lesquelles constituent la charpente bien visible du système, et des courtes racines que sont produites par les longues racines. Les longues racines produisent les bourgeons, mais l'origine des bourgeons est retardé jusqu'au commencement de l'activité du cambium dans les racines. Les courtes racines ne produisent pas les bourgeons. Il paraît que l'activité du cambium dans les longues racines soit corrélative avec l'initiation des bourgeons et l'absence du cambium dans les courtes racines explique probablement leur incapacité à produire les bourgeons.


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