Leaf-shape variation of Paederia foetida in Japan: reexamination of the small, narrow leaf form from Miyajima Island

Compound palm leaf development is unique and consists of two processes. First, the primordial tissue folds through differential growth, forming plications. Second, these plications separate through an abscission-like process, forming leaflets. The second process of leaflet separation allows for the development of compound leaves. The question that this study addresses concerns the development of bifid leaves, as they do not form leaflets but only develop a cleft through an apical incision. The ideal genus to use for this study is Chamaedorea as it includes species with both pinnate and bifid leaves. Chamaedorea fragrans (Ruiz & Pav.) Mart. and Chamaedorea stolonifera H. Wendl. ex Hook. f. were chosen as the species with adult bifid leaves. Although Chamaedorea seifrizii Burret is a pinnate-leaved palm, its juvenile leaves are bifid. Scanning electron microscopy and light microscopy were used to study the development of bifid leaves. Our results indicate that neither of these bifid palms develop separation sites within the lamina, but rather the apical cleft develops through “late leaflet separation” or by an abscission-like process. In contrast, C. seifrizii juvenile leaves exhibit “early leaflet separation” when developing the apical cleft.

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Positional variation rather than salt stress dominates changes in three-dimensional leaf shape patterns in cucumber canopies

in silico Plants ◽

10.1093/insilicoplants/diz011 ◽

2019 ◽

Author(s):

Dominik Schmidt ◽

Katrin Kahlen

Keyword(s):

Salt Stress ◽

Stress Responses ◽

Leaf Shape ◽

Three Dimensional ◽

Size Variation ◽

Canopy Architecture ◽

Shape Variation ◽

Stress Study ◽

Salinity Levels ◽

Adaptation Processes

Abstract Leaf shape plays a key role in the interaction of a plant with its environment, best-known in the plant’s light harvest. Eﬀects of the environment on the interplay of canopy architecture and physiological functioning can be estimated using functional-structural plant models (FSPMs). In order to reduce the complexity of canopy simulations, leaf shape models used in FSPMs are often simple prototypes scaled to match current leaf area. L-Cucumber is such an FSPM, whose leaf prototype mimics average real leaf shape of unstressed cucumber plants well. However, adaptation processes or stress responses may lead to non-proportional changes in leaf geometries, which, for example, could aﬀect length to width ratios or curvatures. The current leaf shape model in L-Cucumber is static and hence does not incorporate changes in leaf shape within or between plants. Thus, the aim of this study was to estimate leaf shape variation and exemplarily study its eﬀects on FSPM simulations. Three-dimensional leaf coordinate data from a salt stress study were analysed with a robust Bayesian mixed-eﬀects model for estimating leaf shape depending on rank, size and salinity. Results showed that positional and size variation rather than salinity levels dominated 3D leaf shape patterns of cucumber. Considering variable leaf shapes in relation to this main sources of variation in L-Cucumber simulations, only minor eﬀects compared to a realistic, yet static average shape were found. However, with similar computational demands variation in shapes other studies highly sensitive to shape dynamics, for example, pesticide spraying might be aﬀected more strongly.

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The structure of allozyme and leaf shape variation in isolated, range-margin populations of the shrub Hippocrepis emerus (Leguminosae)

Ecography ◽

10.1111/j.1600-0587.1995.tb00130.x ◽

1995 ◽

Vol 18 (3) ◽

pp. 276-285 ◽

Cited By ~ 14

Author(s):

Mikael Lonn ◽

Honor C. Prentice

Keyword(s):

Leaf Shape ◽

Shape Variation ◽

Range Margin

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The significance of shared leaf shape in Alseuosmia pusilla and Pseudowintera colorata

Botany ◽

10.1139/cjb-2016-0049 ◽

2016 ◽

Vol 94 (7) ◽

pp. 555-564 ◽

Cited By ~ 4

Author(s):

Karl G. Yager ◽

H. Martin Schaefer ◽

Kevin S. Gould

Keyword(s):

Spatial Variation ◽

Plant Species ◽

Altitudinal Gradient ◽

Leaf Shape ◽

Sympatric Species ◽

Spatially Explicit ◽

Shape Variation ◽

Geometric Morphometric ◽

Leaf Characteristics ◽

Shape And Size

Leaf shape, size, and colour are used by herbivores to identify sources of palatable foliage for food. It is possible, therefore, that an undefended plant might gain protection from herbivores by matching leaf characteristics of a chemically defended species. We demonstrate the use of a geometric morphometric approach to quantify spatial variation in leaf shape and size across populations of Pseudowintera colorata (Raoul) Dandy, and a putative Batesian mimic, Alseuosmia pusilla (Colenso) A. Cunningham. These are unrelated, sympatric species that, to the human eye, bear strikingly similar foliage. Using the Cartesian coordinates of leaf margins as descriptors of leaf shape, we found that in the chemically defended P. colorata, leaves were morphologically distinct from all of the neighbouring species except for the undefended A. pusilla. Alseuosmia pusilla individuals were more similar to neighbouring than to distant P. colorata, and 90% of leaf shape variation in the two species varied similarly across an altitudinal gradient. The data are consistent with Batesian mimicry, wherein the conspicuous characteristic of a defended model is replicated by an undefended mimic across its entire growing range. Our study provides the first detailed and powerful quantitative leaf shape evidence of leaf shape being matched between an undefended plant species to a chemically defended unrelated species across a shared growing range, and highlights the importance of using a spatially explicit morphometric method when investigating leaf shape, especially in relation to plant mimicry.

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The evolution and functional significance of leaf shape in the angiosperms

Functional Plant Biology ◽

10.1071/fp11057 ◽

2011 ◽

Vol 38 (7) ◽

pp. 535 ◽

Cited By ~ 224

Author(s):

Adrienne B. Nicotra ◽

Andrea Leigh ◽

C. Kevin Boyce ◽

Cynthia S. Jones ◽

Karl J. Niklas ◽

...

Keyword(s):

Functional Significance ◽

Leaf Shape ◽

Future Research ◽

Shape Variation ◽

Growth And Survival ◽

Developmental Sequences ◽

Evolutionary Context ◽

Biomechanical Constraints ◽

Flower Form ◽

Hot Environments

Angiosperm leaves manifest a remarkable diversity of shapes that range from developmental sequences within a shoot and within crown response to microenvironment to variation among species within and between communities and among orders or families. It is generally assumed that because photosynthetic leaves are critical to plant growth and survival, variation in their shape reflects natural selection operating on function. Several non-mutually exclusive theories have been proposed to explain leaf shape diversity. These include: thermoregulation of leaves especially in arid and hot environments, hydraulic constraints, patterns of leaf expansion in deciduous species, biomechanical constraints, adaptations to avoid herbivory, adaptations to optimise light interception and even that leaf shape variation is a response to selection on flower form. However, the relative importance, or likelihood, of each of these factors is unclear. Here we review the evolutionary context of leaf shape diversification, discuss the proximal mechanisms that generate the diversity in extant systems, and consider the evidence for each the above hypotheses in the context of the functional significance of leaf shape. The synthesis of these broad ranging areas helps to identify points of conceptual convergence for ongoing discussion and integrated directions for future research.

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Why More Leaflets? The Role of Natural Selection in Shaping the Spatial Pattern of Leaf-Shape Variation in Oxytropis diversifolia (Fabaceae) and Two Close Relatives

Frontiers in Plant Science ◽

10.3389/fpls.2021.681962 ◽

2021 ◽

Vol 12 ◽

Author(s):

Hui Wang ◽

Pei-Liang Liu ◽

Jian Li ◽

Han Yang ◽

Qin Li ◽

...

Keyword(s):

Natural Selection ◽

Spatial Pattern ◽

Leaf Shape ◽

Morphological Differentiation ◽

Clinal Variation ◽

Shape Variation ◽

Association Analyses ◽

Intergenic Regions ◽

Close Relatives

Leaf shape exhibits tremendous diversity in angiosperms. It has long been argued that leaf shape can affect major physiological and ecological properties of plants and thus is likely to be adaptive, but the evolutionary evidence is still scarce. Oxytropis diversifolia (Fabaceae) is polymorphic for leaf shape (1 leaflet, 1–3 leaflets, and 3 leaflets) and exhibits clinal variation in steppes of Nei Mongol, China. With two close relatives predominantly fixed for one phenotype as comparison (Oxytropis neimonggolica with 1 leaflet and Oxytropis leptophylla with 5–13 leaflets), we used a comprehensive cline-fitting approach to assess the role of natural selection in shaping the spatial pattern of leaf-shape variation in this system. For 551 individuals sampled from 22 populations, we quantified leaf-morphological differentiation, evaluated patterns of neutral genetic variation using five chloroplast DNA intergenic regions and 11 nuclear microsatellite loci, and performed microhabitat and macroclimatic-association analyses. We found that 1-leaflet proportions in O. diversifolia populations significantly increased from west to east, and three phenotypes also differed in leaflet-blade size. However, compared with the other two species, populations of O. diversifolia showed little neutral genetic differentiation, and no population structure was detected at either marker. We further revealed that the leaf-shape cline could largely be explained by three macroclimatic variables, with leaflet number decreasing and leaflet-blade size increasing with annual precipitation and showing the reverse trends with temperature seasonality and isothermality. Our results suggest that spatially varying abiotic environmental factors contribute to shape the leaf-shape cline in O. diversifolia, while the interspecific pattern may be due to both local adaptation and historical events.

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Digital Morphometrics: A Tool for Leaf Morpho- Taxonomical Studies

10.35940/ijb.b2001.101221 ◽

2021 ◽

Vol 1 (2) ◽

pp. 1-7

Author(s):

Kavi K. Oza ◽

Rinku J. Desai ◽

Vinay M. Raole*

Keyword(s):

Principal Component Analysis ◽

Abiotic Factors ◽

Leaf Shape ◽

Principal Component ◽

Component Analysis ◽

Herbarium Specimens ◽

Fourier Descriptors ◽

Shape Variation ◽

Quantitative Analysis Method ◽

Elliptic Fourier Descriptors

Leaves are most important part of the plant and can be used for the identification of a taxon. An appropriate understanding of leaf development in terms of shape and responsible abiotic factors is necessary for improvement in plant. Leaf shape variation could be evaluated successfully, and the symmetrical and asymmetrical elements of the overall shape variation could be detected. The aim of the present study was to establish a quantitative analysis method of leaf shape by elliptic Fourier descriptors and principal component analysis (EF-PCA). EF-PCA describes an overall shape mathematically by transforming coordinate information concerning its contours into elliptic Fourier descriptors (EFDs) and summarizing the EFDs by principal component analysis. We can be able to extract six variables by using leaf specimen images from field and herbarium specimens. In the present study, total leaf area with respect to notch area is more variable within species. Within a species the major source of the symmetrical elements may be governed by genotypic features and the asymmetrical elements are strongly affected by the environment. We could discuss the value of morphometrics to detect subtle morphological variation which may be undetectable by human eye.

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Geometric and topological approaches to shape variation in Ginkgo leaves

Royal Society Open Science ◽

10.1098/rsos.210978 ◽

2021 ◽

Vol 8 (11) ◽

Author(s):

Haibin Hang ◽

Martin Bauer ◽

Washington Mio ◽

Luke Mander

Keyword(s):

Leaf Shape ◽

Persistent Homology ◽

Leaf Size ◽

Geometric Method ◽

Topological Method ◽

Shape Variation ◽

Short Shoot ◽

Plant Trait ◽

Elastic Curves ◽

Fossil Leaves

Leaf shape is a key plant trait that varies enormously. The range of applications for data on this trait requires frequent methodological development so that researchers have an up-to-date toolkit with which to quantify leaf shape. We generated a dataset of 468 leaves produced by Ginkgo biloba , and 24 fossil leaves produced by evolutionary relatives of extant Ginkgo . We quantified the shape of each leaf by developing a geometric method based on elastic curves and a topological method based on persistent homology. Our geometric method indicates that shape variation in modern leaves is dominated by leaf size, furrow depth and the angle of the two lobes at the leaf base that is also related to leaf width. Our topological method indicates that shape variation in modern leaves is dominated by leaf size and furrow depth. We have applied both methods to modern and fossil material: the methods are complementary, identifying similar primary patterns of variation, but also revealing different aspects of morphological variation. Our topological approach distinguishes long-shoot leaves from short-shoot leaves, both methods indicate that leaf shape influences or is at least related to leaf area, and both could be applied in palaeoclimatic and evolutionary studies of leaf shape.

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