scholarly journals Contributions of bark and tension wood and role of the G-layer lignification in the gravitropic movements of 21 tropical tree species

2019 ◽  
Vol 76 (4) ◽  
Author(s):  
Barbara Ghislain ◽  
Tancrède Alméras ◽  
Jonathan Prunier ◽  
Bruno Clair
Keyword(s):  
Tensile Stress ◽  
Tree Species ◽  
Tension Wood ◽  
Tropical Species ◽  
Tropical Tree Species ◽  
Motor Efficiency ◽  
Maturation Strain ◽  
Similar Motor ◽  
Stem Curvature

Abstract Key message Gravitropic movements in angiosperm woody stems are achieved through the action of bark and/or wood motor, depending on the bark and wood fibre anatomy (with trellis structure or not; with G-layers or not). Bark motor is as efficient as wood motor to recover from tilting in young trees of 21 tropical species. Context Angiosperm trees produce tension wood to control their orientation through changes in stem curvature. Tension wood is classified into 3 anatomical groups: with unlignified G-layer, with lignified G-layer and without G-layer. Aims This study aimed at assessing whether this anatomical diversity reflects a diversity in efficiency of gravitropic movement. Methods The study was conducted on tropical seedling from the three anatomical groups. Seedlings were staked and grown tilted. At the end of the experiment, changes in curvature when releasing the stem from the stake and when removing bark were measured. Three parameters were computed to compare the global efficiency of gravitropism (stem gravitropic efficiency) and the specific efficiency of motor mechanism based on wood (maturation strain of tension wood) and bark (standardized debarking curvature). Results The maturation strain of tension wood was similar between species with unlignified and lignified G-layer. Species without G-layer exhibited low maturation strain and large debarking curvature, showing they rely on bark for gravitropism. Bark and wood achieved similar motor efficiency. Conclusion Lignin does not affect the generation of tensile stress in the G-layer. Bark can be as efficient as wood as a motor of gravitropic movements.

scholarly journals Metabolome-Wide, Phylogenetically Controlled Comparison Indicates Higher Phenolic Diversity in Tropical Tree Species

Plants ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 554
Author(s):  
Guille Peguero ◽  
Albert Gargallo-Garriga ◽  
Joan Maspons ◽  
Karel Klem ◽  
Otmar Urban ◽  
...  
Keyword(s):  
Tree Species ◽  
Phylogenetic Diversity ◽  
Multilevel Models ◽  
Secondary Compounds ◽  
Tropical Tree ◽  
Tropical Species ◽  
Tropical Plants ◽  
Tropical Tree Species ◽  
Antagonistic Interactions

Tropical plants are expected to have a higher variety of defensive traits, such as a more diverse array of secondary metabolic compounds in response to greater pressures of antagonistic interactions, than their temperate counterparts. We test this hypothesis using advanced metabolomics linked to a novel stoichiometric compound classification to analyze the complete foliar metabolomes of four tropical and four temperate tree species, which were selected so that each subset contained the same amount of phylogenetic diversity and evenness. We then built Bayesian phylogenetic multilevel models to test for tropical–temperate differences in metabolite diversity for the entire metabolome and for four major families of secondary compounds. We found strong evidence supporting that the leaves of tropical tree species have a higher phenolic diversity. The functionally closer group of polyphenolics also showed moderate evidence of higher diversity in tropical species, but there were no differences either for the entire metabolome or for the other major families of compounds analyzed. This supports the interpretation that this tropical–temperate contrast must be related to the functional role of phenolics and polyphenolics.

Seedling growth of two pioneer tropical tree species in Competition: The role of arbuscular mycorrhizae

Euphytica ◽  
2004 ◽  
Vol 138 (2) ◽  
pp. 113-121 ◽  
Author(s):  
Patricia Guadarrama ◽  
Javier Álvarez-Sánchez ◽  
Oscar Briones
Keyword(s):  
Seedling Growth ◽  
Tree Species ◽  
Arbuscular Mycorrhizae ◽  
Tropical Tree ◽  
Tropical Tree Species

Role of pollen production in mating success in some tropical tree species

2014 ◽  
Vol 38 (1) ◽  
pp. 107-112 ◽  
Author(s):  
Vinod Prasad Khanduri ◽  
Kewat Sanjay Kumar ◽  
Chandra Mohan Sharma
Keyword(s):  
Mating Success ◽  
Tree Species ◽  
Tropical Tree ◽  
Pollen Production ◽  
Tropical Tree Species

scholarly journals Diversity of anatomical structure of tension wood among 242 tropical tree species

IAWA Journal ◽  
2019 ◽  
Vol 40 (4) ◽  
pp. 765-784 ◽  
Author(s):  
Barbara Ghislain ◽  
Julien Engel ◽  
Bruno Clair
Keyword(s):  
Wood Density ◽  
Tree Species ◽  
Tension Wood ◽  
Wood Anatomy ◽  
Tropical Tree ◽  
Blue Staining ◽  
Common Mechanism ◽  
Vertical Position ◽  
Normal Wood ◽  
Tropical Tree Species

ABSTRACT Angiosperm trees produce tension wood to actively control their vertical position. Tension wood has often been characterised by the presence of an unlignified inner fibre wall layer called the G-layer. Using this definition, previous reports indicate that only one-third of all tree species have tension wood with G-layers. Here we aim to (i) describe the large diversity of tension wood anatomy in tropical tree species, taking advantage of the recent understanding of tension wood anatomy and (ii) explore any link between this diversity and other ecological traits of the species. We sampled tension wood and normal wood in 432 trees from 242 species in French Guiana. The samples were observed using safranin and astra blue staining combined with optical microscopy. Species were assigned to four anatomical groups depending on the presence/absence of G-layers, and their degree of lignification. The groups were analysed for functional traits including wood density and light preferences. Eighty-six% of the species had G-layers in their tension wood which was lignified in most species, with various patterns of lignification. Only a few species did not have G-layers. We found significantly more species with lignified G-layers among shade-tolerant and shade-demanding species as well as species with a high wood density. Our results bring up-to-date the incidence of species with/without G-layers in the tropical lowland forest where lignified G-layers are the most common anatomy of tension wood. Species without G-layers may share a common mechanism with the bark motor taking over the wood motor. We discuss the functional role of lignin in the G-layer.

scholarly journals Processes Influencing Floral Initiation and Bloom: The Role of Phytohormones in a Conceptual Flowering Model

2000 ◽  
Vol 10 (4) ◽  
pp. 733-739 ◽  
Author(s):  
Thomas L. Davenport
Keyword(s):  
Tree Species ◽  
Mangifera Indica ◽  
Fruit Tree ◽  
Tropical Species ◽  
Physiological Mechanisms ◽  
Shoot Initiation ◽  
Tropical Environments ◽  
The Impact ◽  
Subtropical Fruit

The reproductive phenologies of temperate fruit tree species are briefly introduced and compared to the reproductive phenologies of three tropical and subtropical fruit tree species. The impact of leaf and fruit development and the phytohormones they may produce on the reproductive or vegetative fate of bourse buds in apple spurs serves as the model to discuss temperate fruit flowering. In contrast, conceptual models of citrus (Citrus L.), mango (Mangifera indica L.), and lychee (Litchi chinensis Sonn.) flowering are described which propose physiological mechanisms for both flowering and vegetative flushing in trees grown in subtropical and tropical environments. Possible roles for auxin and cytokinins in shoot initiation and for gibberellins and a putative florigenic promoter in induction are discussed as they relate to the physiology of flowering and vegetative flushing of tropical species. Successful application of these conceptual flowering models through the use of growth regulators and other horticultural management techniques to control flowering of citrus, mango, and lychee is described.

Differences of the stem vascular system across populations of two tropical species under contrasting water conditions

IAWA Journal ◽  
2021 ◽  
pp. 1-18
Author(s):  
Marcela Blagitz ◽  
Anselmo Nogueira ◽  
Carmen Regina Marcati
Keyword(s):  
Water Availability ◽  
Tree Species ◽  
Structural Variation ◽  
Secondary Xylem ◽  
Vascular System ◽  
Tropical Tree ◽  
System Structure ◽  
Tropical Species ◽  
Tropical Tree Species ◽  
Water Conditions

Abstract Structural differences in the secondary vascular tissues among habitats can contribute to understanding species performances, especially regarding water and photosynthate transport. The pattern of association between the secondary xylem tissue and water availability from the environment has been widely studied, unlike the secondary phloem, which has been barely explored. Here, we evaluated the structural variation of the secondary xylem and phloem in stems of four populations of two tropical tree species under contrasting water conditions. We also investigated the mirrored structure between both tissues. At dry sites, Moquiniastrum polymorphum had higher vessel density, thicker xylem fibers cell walls, and taller rays in both tissues commonly associated with safe transport, in agreement with our expectations. In contrast, the populations of Zanthoxylum rhoifolium had most features in disagreement with the water availability of each site. The perforation and sieve plates, the ray composition, and the axial parenchyma were similar in the two tree species’ xylem and phloem tissues. However, the quantitative descriptors of cell sizes were not correlated between the xylem and phloem. In general, there is a different pattern of morphological variation across sites in the two tropical tree species, highlighting that any generalization regarding the vascular system structure across environments should be avoided. Xylem and phloem revealed a mirrored structure in a few qualitative features, not followed by the dimensions of different cell types. Future research needs to explore the causes of the unexpected structural variation in the vascular system across populations in tropical tree species.

scholarly journals Diversity in the organisation and lignification of tension wood fibre walls – A review

IAWA Journal ◽  
2017 ◽  
Vol 38 (2) ◽  
pp. 245-265 ◽  
Author(s):  
Barbara Ghislain ◽  
Bruno Clair
Keyword(s):  
Cell Wall ◽  
Tensile Stress ◽  
Cell Walls ◽  
Tension Wood ◽  
Anatomical Structure ◽  
Wood Fibre ◽  
Tropical Species ◽  
Wood Fibres ◽  
Staining Techniques

Tension wood, a tissue developed by angiosperm trees to actively recover their verticality, has long been defined by the presence of an unlignified cellulosic inner layer in the cell wall of fibres, called the G-layer. Although it was known that some species have no G-layer, the definition was appropriate since it enabled easy detection of tension wood zones using various staining techniques for either cellulose or lignin. For several years now, irrespective of its anatomical structure, tension wood has been defined by its high mechanical internal tensile stress. This definition enables screening of the diversity of cell walls in tension wood fibres. Recent results obtained in tropical species with tension wood with a delay in the lignification of the G-layer opened our eyes to the effective presence of large amounts of lignin in the G-layer of some species. This led us to review older literature mentioning the presence of lignin deposits in the G-layer and give them credit. Advances in the knowledge of tension wood fibres allow us to reconsider some previous classifications of the diversity in the organisation of the fibre walls of the tension wood.

SEM Study of Tension Wood Fiber Morphology and its Effect on Paper Properties

1977 ◽  
Vol 35 ◽  
pp. 308-309
Author(s):  
K. W. Robinson
Keyword(s):  
Tension Wood ◽  
Wood Fiber ◽  
Strength Properties ◽  
Fiber Morphology ◽  
Paper Properties ◽  
Pure Cellulose ◽  
Short Rotation ◽  
Hardwood Trees ◽  
Sem Study

Tension wood (TW) is an abnormal tissue of hardwood trees; although it has been isolated from most parts of the tree, it is frequently found on the upper side of branches and leaning stems. TW has been classically associated with geotropic alignment, but more recently it has been associated with fast growth. Paper made from TW is generally lower in strength properties. Consequently, the paper industries' growing dependence on fast growing, short- rotation trees will result in higher amounts of TW in the final product and a corresponding reduction in strength.Relatively few studies have dealt with the role of TW in the structure of paper. It was suggested that the lower strength properties of TW were due to a combination of factors, namely, its unique morphology, compression failures in the cell wall, and lower hemicellulose content. Central to the unique morphology of the TW fiber is the thick gelatinous layer (G-layer) composed almost entirely of pure cellulose.

Non-native poeciliids in hot water: the role of thermal springs in facilitating invasion of tropical species

Hydrobiologia ◽  
2021 ◽  
Author(s):  
Quenton M. Tuckett ◽  
Katelyn M. Lawson ◽  
Taylor N. Lipscomb ◽  
Jeffrey E. Hill ◽  
Wesley M. Daniel ◽  
...  
Keyword(s):  
Hot Water ◽  
Thermal Springs ◽  
Tropical Species
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