scholarly journals Morpho-anatomical characterization of diaspores and seedlings of Livistona rotundifolia

2016 ◽  
Vol 22 (3) ◽  
pp. 249 ◽  
Author(s):  
Fábio Alessandro Padilha Viana ◽  
Anne Pinheiro Costa ◽  
Fabíola Vitti Moro ◽  
Kathia Fernandes Lopes Pivetta
Keyword(s):  
Root Hairs ◽  
Root Apex ◽  
Vascular Cylinder ◽  
Seedling Production ◽  
Seedling Morphology ◽  
Important Species ◽  
Morphological Studies ◽  
Lack Of Information ◽  
Cotyledonary Petiole ◽  
Well Differentiated

Livistona rotundifolia (Lam.) Mart. (Arecaceae) is an ornamentally important species used for landscaping and commonly grown as a potted plant. However, seedling production is hindered by the lack of information available about the species germination process and it could be subsidized by seed and seedling anatomical and morphological studies. Therefore, this study aimed at describing L. rotundifolia diaspore morphology in addition to seedling morphology and anatomy. Germination is tubular remote and begins with the opening of a circular operculum in the fruit endocarp through which the cotyledonary petiole is emitted. The endosperm is consumed as cotyledonary petiole grows. Eophyll is covered by two leaf sheaths and the first L. rotundifolia leaves are simple and lanceolate, with longitudinal and parallel veins. The developing cotyledonary petiole presents root hairs and a typical stem structure. The cotyledonary petiole/root transition region shows secondary root emission, parenchyma cells, and groups of fiber bundles. Roots present a well-defined cortex with polyarc vascular cylinder. Cortex and vascular cylinder are not well-differentiated in the root apex. The results of this study will contribute to the overall biology of L. rotundifolia, as well as to seedling production and species identification, subsidizing regeneration and conservation studies.

Cytological and histochemical characteristics of the axenic root surface of Alnus glutinosa

1986 ◽  
Vol 64 (10) ◽  
pp. 2216-2226 ◽  
Author(s):  
Yves Prin ◽  
Mireille Rougier
Keyword(s):  
Cell Wall ◽  
Root Hair ◽  
Root Hairs ◽  
Root Apex ◽  
Alnus Glutinosa ◽  
Root Surface ◽  
Infection Process ◽  
Root Cap ◽  
A Cell ◽  
Histochemical Tests

The aim of the present study was to investigate the Alnus root surface using seedlings grown axenically. This study has focused on root zones where infection by the symbiotic actinomycete Frankia takes place. The zones examined extend from the root cap to the emerging root hair zone. The root cap ensheaths the Alnus root apex and extends over the root surface as a layer of highly flattened cells closely appressed to the root epidermal cell wall. These cells contain phenolic compounds as demonstrated by various histochemical tests. They are externally bordered by a thin cell wall coated by a thin mucilage layer. The root cap is ruptured when underlying epidermal cells elongate, and cell remnants are still found in the emerging root hair zone. Young emerging root hairs are bordered externally by a cell wall covered by a thin mucilage layer which reacts positively to the tests used for the detection of polysaccharides, glycoproteins, and anionic sites. The characteristics of the Alnus root surface and the biological function of mucilage and phenols present at the root surface are discussed in relation to the infection process.

Rhythmic patterns of nutrient acquisition by wheat roots

2002 ◽  
Vol 29 (5) ◽  
pp. 595 ◽  
Author(s):  
Sergey Shabala ◽  
Andrew Knowles
Keyword(s):  
Root Zone ◽  
Root Hairs ◽  
Rhythmic Activity ◽  
Root Apex ◽  
Root Surface ◽  
Ion Flux ◽  
Nutrient Acquisition ◽  
Wheat Roots ◽  
Non Invasive ◽  
Functional Zone

Oscillatory patterns in H+, K+, Ca2+ and Cl- uptake were observed at different regions of the root surface, including root hairs, using a non-invasive ion flux measuring technique (the MIFE™ technique). To our knowledge, this is the first report of ultradian oscillations in nutrient acquisition in the mature root zone. Oscillations of the largest magnitude were usually measured in the elongation region, 2–4 mm from the root apex. There were usually at least two oscillatory components present for each ion measured: fast, with periods of several minutes; and slow, with periods of 50–80 min. Even within the same functional zone, the periods of ion flux oscillations were significantly different, suggesting that they are driven by some internal mechanisms located in each cell rather than originating from one ‘central clock pacemaker’. There were also significant changes in the oscillatory characteristics (both periods and amplitudes) of fluxes from a single small cluster of cells over time. Analysis of phase shifts between oscillations in different ions suggested that rhythmic activity of a plasma membrane H+-pump may be central to observed rhythmic nutrient acquisition by plant roots. We discuss the possible adaptive significance of such an oscillatory strategy for root nutrient acquisition.

scholarly journals The Research of Standardized Protocols for Dog Involvement in Animal-Assisted Therapy: A Systematic Review

Animals ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 2576
Author(s):  
Antonio Santaniello ◽  
Susanne Garzillo ◽  
Serena Cristiano ◽  
Alessandro Fioretti ◽  
Lucia Francesca Menna
Keyword(s):  
Systematic Review ◽  
Web Of Science ◽  
Scientific Literature ◽  
Training Programs ◽  
Animal Assisted Therapy ◽  
Inclusion Criteria ◽  
Important Species ◽  
Lack Of Information ◽  
Meta Analyses ◽  
And Training

Dogs are considered the most important species involved in animal-assisted therapy (AAT), and the scientific literature focuses on the benefits linked to the involvement of dogs in various therapeutic areas. In this study, we carried out a systematic review according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, exploring the scientific literature from the last 5 years (2016–2021) on three databases (PubMed, Scopus, and Web of Science) to highlight the characteristics of the dogs involved in AATs. Based on the scientific literature relevant to such dogs, we considered different parameters (i.e., number, age, sex, breed, temperament, methods of choice and training, health status, research goals, and activities with dogs) to include studies in our paper. After screening 4331 papers identified on the searched databases, we selected 38 articles that met the inclusion criteria. Analysis of the included articles showed that the characteristics of the dogs were neglected. Our findings indicated a lack of information about the dogs, as well as the absence of standardized and univocal criteria for dog selection, training programs, and health protocols.

scholarly journals Morphological integration between seeds and seedlings of Hymenaea courbaril

2020 ◽  
Author(s):  
Leonardo de Lima Pereira Regnier
Keyword(s):  
Seed Weight ◽  
Morphological Integration ◽  
Lateral Vein ◽  
Seedling Production ◽  
Central Question ◽  
Moderate Correlation ◽  
Important Species ◽  
Hymenaea Courbaril ◽  
Population Origin ◽  
Collar Diameter

ABSTRACTMorphological integrations are unknown to forestry seeds. Understanding if seed measurements could predict its future seedlings features is a central question in seedling production. Hymenaea courbaril is an important species in this context and to the applied forestry. Thus, this study aimed to understand how some seedling features, could be related to the seed weight, and be affected by the population origin. The measurements consisted of seedling collar diameter, weight, protophilus area, central and lateral vein. Seed weight consistently varied between the populations in the study. Both populations had higher weight ranges than mentioned in the literature. There was no strong evidence that greater seed weight requires lesser time to germinate, conflicting with previous information. All the measurements presented enough shreds of evidence to be considered different when comparing the populations, except for the protophilus area and lateral vein length. All the studied measurements presented low correlation indexes to seed weight, except for seedling collar diameter, and seedling weight, which presented a moderate correlation. Protophilus elongation pattern was strongly associated with the leaf width when compared to midvein.

The early development of nodal adventitious roots with root hairs and root hair deformations by Elodea nuttallii (Planchon) H. St. Johns

2020 ◽  
Vol 194 (2) ◽  
pp. 141-149
Author(s):  
Susanne Halbedel ◽  
Nicole Weinert
Keyword(s):  
Ecosystem Services ◽  
Root Hair ◽  
Adventitious Roots ◽  
Vascular Plant ◽  
Root Hairs ◽  
Coarse Grained ◽  
Root Tip ◽  
Elodea Nuttallii ◽  
Important Species ◽  
Aquatic Vascular Plant

Elodea nuttallii is a globally distributed aquatic vascular plant that provides many ecosystem services. In the sediment its roots fulfill important geochemical functions and initiate biological interactions within the rhizosphere. However, the macro-anatomy and development of its roots remained widely uncharacterized. This study aims to analyze the early morphogenesis of Elodeas roots and their general macro-anatomy. Therefore, plants free of roots were planted on two different sediment types and harvested along an individual time axis after the first roots were developed. All plants were photographed, measured and the roots were microscopically analyzed. Elodea has nodal adventitious roots, non-woody and from shoots. All roots have a root tip with a well-developed apical meristem and a root cap, an elongation zone, and a well-developed maturation zone with root hairs. Root hair deformations like swollen root hairs, swollen root hair tips, and branched root hairs most often developed when plants were grown on nutrient-poor, coarse-grained sediment. We here present a first description of the morpho- genesis and macro-anatomy of roots developed by E. nuttallii. This work will improve our understanding of this important species and foster further studies on the coupling between physiological processes, the morphogenesis, anatomy, ecosystem services, economical use, and management strategies related to E. nuttallii.

scholarly journals Taxonomic study of some medicinally important species of Swertia L. (Gentianaceae) in Nepal

2010 ◽  
Vol 6 ◽  
pp. 18-24 ◽  
Author(s):  
Dilli Prasad Rijal
Keyword(s):  
Raw Materials ◽  
Morphological Characteristics ◽  
Plant Science ◽  
Illegal Trade ◽  
Important Species ◽  
Traditional Medicines ◽  
Morphological Studies ◽  
The World ◽  
Key Characters ◽  
Selection Of

Among 100 species of Swertia reported from the world, Nepal harbors 30 species along with four varieties. In Nepal, species of Swertia are highly exploited as raw materials for different traditional medicines. Among them, S. chirayita, a vulnerable species, has been considered to be superior in medicine and trade. One of the main issues in its trade is adulteration with other species which are considered to be inferior in medicinal quality. Species which are mixed with S. chirayita are S. angustifolia, S. ciliata, S. dilatata, S. paniculata, S. racemosa, etc. There is a need for the selection of most important morphological characteristics for instant identification of different species of Swertia to check illegal trade as well as adulteration. This paper aims to provide the most important identifying characters of eight species of Swertia traded from Nepal on the basis of their morphological studies. Color of the petal, number of floral parts (tetramerous vs. pentamerous) and number of glands in petal are the key characters for the identification of the species. Key-words: adulteration; medicinal plant; morphological characters.DOI: 10.3126/botor.v6i0.2906 Botanica Orientalis - Journal of Plant Science (2009) 6: 18-24

Nutrient transfer in arbuscular mycorrhizas: how are fungal and plant processes integrated?

2001 ◽  
Vol 28 (7) ◽  
pp. 685 ◽  
Author(s):  
Sally E. Smith ◽  
Sandy Dickson ◽  
F. Andrew Smith
Keyword(s):  
Mycorrhizal Fungi ◽  
Small Diameter ◽  
Root Hairs ◽  
Root Apex ◽  
Am Fungi ◽  
Transport Processes ◽  
High Affinity ◽  
External Hyphae ◽  
Mycorrhizal Roots ◽  
External Mycelium

This review brings together recent work on the coordination of transport processes between fungus and plant symbionts in arbuscular mycorrhizal (AM) symbioses, and focuses on new information on the diversity in structure and function of interfaces and their potential roles in transport processes. We consider the way that fungal activity is polarised to absorb mineral nutrients (especially phosphorus, P) in soil, transport them to the root and release them to the plant. Conversely, the fungal structures within the root appear to be specialised to absorb sugars, which the external mycelium cannot do. The external mycelium depends on a supply of lipid, transported from within the root. High affinity P transporters expressed in the root apices and root hairs of non-mycorrhizal roots, and most probably mycorrhizal roots, absorb P actively. This can result in the development of P depletion zones, so that a low concentration of P at the absorbing surfaces limits further uptake. The external hyphae of AM fungi extend well beyond the depletion zone, accessing supplies of P at a distance and in narrow soil pores, that is absorbed actively by a high affinity P transporter expressed in these small diameter hyphae. Translocation of P within the hyphae and transfer to the plant results in much higher rates of uptake (inflows) by mycorrhizal than non-mycorrhizal roots. The possible role of polyphosphate (polyP) in this process is discussed in the light of new data. Within the root, P is lost from the fungal structures to the interfacial apoplast by an unknown mechanism, and is absorbed by the root cortical cells. The expression of a high affinity P transporter and H + -ATPase in arbuscule-containing cells indicates that these are probably the sites of fungus/plant P transfer. The site of sugar transfer from plant to fungus has not yet been established. At the whole plant level, plant uptake systems located in the youngest regions of the root are positioned to absorb P from undepleted soil, into which the root apex has just grown. In older regions of the roots, colonised by mycorrhizal fungi, the external mycelium will take over the absorptive role and overcome the difficulties posed by the slow diffusion of P in soil.

A taxonomic revision and morphological variation within Eucalyptus series Subulatae subseries Oleaginae (Myrtaceae), including the oil mallee complex, of south-western Australia

2005 ◽  
Vol 18 (6) ◽  
pp. 525 ◽  
Author(s):  
D. Nicolle ◽  
M. Byrne ◽  
M. Whalen
Keyword(s):  
Western Australia ◽  
Morphological Variation ◽  
Taxonomic Revision ◽  
Morphological Characters ◽  
Seedling Morphology ◽  
Adult Leaf ◽  
Extensive Field ◽  
Well Differentiated ◽  
Seedling Characters ◽  
Weak Separation

Morphological variation within Eucalyptus series Subulatae subseries Oleaginae, a group of mallee taxa distributed in south-western Australia, was assessed by adult and seedling characteristics. A total of 36 adult morphological characters and 20 seedling characters was included in phenetic analyses of 82 individuals representing 29 populations covering all the taxa and the broad geographical distribution of the series. The phenetic analyses indicate relatively weak separation of all previously recognised taxa within E. subser. Oleaginae, except for E. longissima (previously referred to as E. grasbyi), which is distinctive in its seedling morphology, and to a lesser degree, E. ultima, which is also most easily distinguished by seedling morphology. E. eremicola, E. peeneri and E. sublucida are not well differentiated from one another, differing significantly only in adult leaf colour and gloss. The three previously recognised species of the oil mallee complex (E. kochii, E. plenissima and E. ‘horistes’) are also only weakly differentiated from one another. Two variants within E. kochii were observed to differ from each other in several adult vegetative and floral characteristics and are recognised at the subspecific level. A new taxonomy for E. subser. Oleaginae is presented, based on phenetic analyses combined with extensive field, glasshouse and herbarium examination of all taxa in the subseries. A new species is described (E. longissima Nicolle sp. nov.) to accommodate populations of mallees previously erroneously referred to E. grasbyi. New combinations are made for E. peeneri [E. eremicola subsp. peeneri (Blakely) Nicolle comb. nov.] and E. oleosa var. borealis [E. kochii subsp. borealis (C. Gardner) Nicolle comb. nov.] and two new subspecies of E. kochii are described (subspp. amaryssia Nicolle and yellowdinensis Nicolle). Eucalyptus sublucida is considered to be synonymous with E. eremicola subsp. peeneri. Keys to the taxa within the subseries are presented.

scholarly journals Seed characterization of Allamanda puberula A. DC. and seedling production

2021 ◽  
Author(s):  
Rosana Sousa Bonfim ◽  
Poliana Moreira Lopes ◽  
Samuel Gonçalves de Araújo ◽  
Marília das Dores Genovez Furtado ◽  
Rafaela Ribeiro de Souza ◽  
...  
Keyword(s):  
Native Species ◽  
Second Phase ◽  
Seedling Production ◽  
Lack Of Information ◽  
Germination Process ◽  
Caatinga Biome ◽  
Two Phases ◽  
Number Of Seeds ◽  
Growth And Allocation

Abstract Allamanda puberula is a native species of the Caatinga biome with ornamental and landscaping potential. However, its potential is little explored due to the lack of information about the biology of its seeds and propagation. In this context, a study was carried out in order to characterize the seeds and their potential to produce seedlings in different containers. The experiments were divided into two phases. The first consisted in the characterization of fruits and seeds by evaluating the number of seeds per fruit, their dimensions (length and width), the weight of a thousand seeds, the number of seeds kg-¹, the degree of moisture, germination and emergence. The second phase consisted in the production of seedlings in a nursery, evaluating the growth over the days after sowing (DAS) (15, 30, 45 and 60 DAS) and the effect of the type of container (trays and tubes) for the formation of the seedlings. The species A. puberula has small seeds and a significant number of seeds per fruit. Apparently, there is no physical impediment or type of dormancy that impairs the germination process of the seeds. Seedlings grown in tubes were better in terms of growth and allocation of biomass. However, the indication of the best cultivation container for A. puberula propagated via seeds will depend on the implantation project and the specific characteristics of the field. The characterization of A. puberula seeds showed satisfactory physiological potential for germination and complete seedling formation in the nursery, enabling success in obtaining seedlings through seminiferous propagation.

Development of Alnus japonica root nodules after inoculation with Frankia strain HFPArI3

1987 ◽  
Vol 65 (8) ◽  
pp. 1647-1657 ◽  
Author(s):  
D. Burgess ◽  
R. L. Peterson
Keyword(s):  
Root Nodules ◽  
Root Hairs ◽  
Vascular Cylinder ◽  
Alnus Japonica ◽  
Frankia Strain ◽  
Cortical Cells ◽  
Starch Grains ◽  
Transmission Electron ◽  
Exotic Tree ◽  
Infected Cells

The ontogeny and structure of nodules on an exotic tree species, Alnus japonica (Thunb.) Steud. were studied for up to 3 months after inoculation of seedlings with a North American Frankia strain, HFPArI3. Nodules developed with Frankia growth first restricted to one side of the developing vascular cylinder. Nodules became multilobed, developed a complex network of vascular cylinders, and infected cortical cells organized in a concentric ring around each vascular cylinder. Each nodule lobe showed a zonation from the meristem basipetally. Cortical cells adjacent to the meristem contained hyphae, while those distal to this zone developed hyphae and endophytic vesicles. Staining for suberin induced fluorescence of root hairs, the endodermal Casparian strip, endophytic vesicle clusters, and periderm. Staining for callose resulted in fluorescence of the encapsulation material at one stage of Frankia development. Infected cells had few, small starch grains, while uninfected cells had several, large starch grains. The adjacent pericycle was multilayered. Its cells, viewed with the transmission electron microscope, had lobed nuclei, small vacuoles, many mitochondria, and dense plastids containing small starch grains.

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