scholarly journals Divergent leaf shapes among Passiflora species arise from a shared juvenile morphology

2016 ◽  
Author(s):  
Daniel H. Chitwood ◽  
Wagner C. Otoni

AbstractPREMISE OF THE STUDYNot only does leaf shape vary between Passiflora species, but between sequential nodes of the vine. The profound changes in leaf shape within Passiflora vines reflect the temporal development of the shoot apical meristem from which leaves are derived and patterned, a phenomenon known as heteroblasty.METHODSWe perform a morphometric analysis of more than 3,300 leaves from 40 different Passiflora species using two different methods: homologous landmarks and Elliptical Fourier Descriptors (EFDs).KEY RESULTSChanges in leaf shape across the vine are first quantified in allometric terms; that is, changes in the relative area of leaf sub-regions expressed in terms of overall leaf area. Shape is constrained to strict linear relationships as a function of size that vary between species. Statistical analysis of leaf shape, using landmarks and EFDs, reveals that species effects are the strongest, followed by interaction effects, and negligible heteroblasty effects. The ability of different nodes to predictively discriminate species and the variability of landmark and EFD traits at each node is then analyzed. Heteroblastic trajectories, the changes in leaf shape between the first and last measured leaves in a vine, are then compared between species in a multivariate space.CONCLUSIONLeaf shape diversity among Passiflora species is expressed in a heteroblastic-dependent manner. Leaf shape is constrained by linear, allometric relationships related to leaf size that vary between species. There is a strong species x heteroblasty interaction effect for leaf shape, suggesting that different leaf shapes between species arise through changes in shape across nodes. The first leaves in the series are not only more like each other, but are also less variable across species. From this similar, shared leaf shape, subsequent leaves in the heteroblastic series follow divergent morphological trajectories. The disparate leaf shapes characteristic of Passiflora species arise from a shared, juvenile morphology.

2017 ◽  
Vol 51 ◽  
pp. 242-250
Author(s):  
M. V. Dulin

Tetralophozia setiformis is a widespread species occurring usually without organs of sexual and asexual reproduction. Gemmae of Tetralophozia setiformis were observed for the second time in Russia and Eurasia in the Northern Urals, Komi Republic. They form compact masses over upper leaves. The compact masses consist largely (70 %) of immature gemmae. Description of gemmae and gemmiparous shoots from the Northern Urals and their comparison with those from the other known localities, namely British Columbia (Canada) and the Murmansk Region (European Russia) were carried out. The gemmiparous plants of T. setiformis from the Northern Urals have approximately the same width as plants without gemmae but they are shorter. The leaves of gemmiparous plants from the Northern Urals are similar to leaves of gemmiparous plants from British Columbia. The leaf shape in upper part of the gemmiparous shoots varies from the typical to ± modified from gemmae production. These leaf shape transitions include reduction of leaf size and lobe number from 4 to 2–3, suppression of development and disappearance of characteristic teeth at the base of sinus. Gemmae size (17 × 22 μm) of plants from the Northern Urals is within variability recorded for plants from the Murmansk Region and British Columbia.


1996 ◽  
Vol 351 (1348) ◽  
pp. 1671-1677 ◽  

Leaves display an enormous array of sizes and shapes. Although these attributes appear to have evolved primarily in response to abiotic conditions in the plant’s habitat, the importance of insect herbivores as additional selective agents is still poorly understood. A necessary requirem ent for leaf size and shape to evolve in response to attack by insects is that insects must respond to and/or be affected by, leaf morphology. We tested leaf-shape preferences in adult flea beetles ( Phyllotreta spp.) feeding on the highly variable rosette leaves of Capsella bursa-pastoris . Contrary to theoretical expectation (Brown & Lawton 1991), leaves with deeply lobed margins were more intensely damaged, both in field-collected and experimental plants. In two ancillary experiments with Capsella , we found that Spodoptera caterpillars showed no preferences for leaf shape, but that adult vine weevils ( Otiorhynchus sulcatus ) did, preferring (as predicted), undivided over divided leaves. We conclude that Brown & Law ton’s (1991) hypothesis is at best weakly supported by laboratory data for vine weevils, refuted by laboratory data for Spodoptera , and consistently refuted by both laboratory and field data for flea beetles. Although the experiment tried to reduce confounding variables to a minimum, interpretation was complicated by correlations between leaf shape and other developmental parameters of the plants, and highlights the difficulty of disentangling leaf-shape effects from other confounding factors.


Phytotaxa ◽  
2017 ◽  
Vol 317 (4) ◽  
pp. 292 ◽  
Author(s):  
JULIO ANTONIO LOMBARDI ◽  
MARCELA SERNA GONZÁLEZ

A new South American species of Salacia (Celastraceae, Salacioideae) found in Colombia and Venezuela, Salacia fugax Lombardi & M.Serna is described here. It is characterized by its indument, small long acuminate leaves with short petioles, branched inflorescences, flowers with an annular-pulvinate disk, and small pyriform fruits. This new species resembles S. mennegana J.Hedin ex Lombardi and S. opacifolia (J.F.Macbr.) A.C.Sm. by its short petioles, leaf shape, slender branched inflorescence, perianth form, and similar disc, but S. fugax differs by its hairs, leaf size and apex, calyx, and fruit size and shape.


2019 ◽  
Vol 14 (3) ◽  
pp. 17-24
Author(s):  
D. M. Anatov ◽  
Z. M. Аsadulaev ◽  
R. M. Osmanov ◽  
K. I. Akhmedova

Aim. The paper presents the results of assessment of the indigenous nature and  degree of similarity of apricot cultivars growing in the collection of the Mountain  Botanical Garden, Gunib, Dagestan, Russia based on a comparative analysis of the  variability of leaf morphological characteristics.   Material and Methods. The material assessed consisted of 33 apricot cultivars of  various ecological and geographical origins aggregated in the following groups: (a)  Dagestan – traditional cultivars; (b) Moscow ‐ selection from the Tsytsin Main Moscow Botanical Garden, Russian Academy of Sciences based on wild forms of Tajikistan and Kyrgyzstan; (c) European and (d) Asian ‐ from Central Asia, Tajikistan, China  and Altai.   Results. The closeness of Dagestan and European varieties in comparison with Asian  and Moscow varieties was shown. Most Dagestan (16 of 19) and European varieties  have round‐shaped leaves (leaf shape index 80‐ 100%), while those from Asia and  the Moscow Botanical Garden have leaves which are elongated elliptical and oval  (60‐80%). Using the method of principal component analysis (PCA), it was established that most cultivars of Dagestan origin have similar leaf shapes and sizes, of  which Tlama kurak (wide‐round), Hekobarsh (elongated) were distinguished by leaf  shape and Esdelik by leaf size.   Conclusion. Based on a discriminant analysis (Squared Mahalanobis Distances), it  was found that the indices of indicators of leaf attributes (width/length of leaf lamina; petiole length/length of lamina; apex angle/corner of leaf base) are more reliable criteria for differentiating apricot varieties into ecological and geographical  groups than their morphological characteristics.  


Author(s):  
M.D. Sow ◽  
A-L. Le Gac ◽  
R. Fichot ◽  
S. Lanciano ◽  
A. Delaunay ◽  
...  

AbstractAs fixed and long living organisms subjected to repeated environmental stresses, trees have developed mechanisms such as phenotypic plasticity that help them to cope with fluctuating environmental conditions. Here, we tested the role DNA methylation as a hub of integration, linking plasticity and physiological response to water deficit in the shoot apical meristem of the model tree poplar (Populus). Using a reverse genetic approach, we compared hypomethylated RNAi-ddm1 lines to wild-type trees for drought tolerance. An integrative analysis was realized with phytohormone balance, methylomes, transcriptomes and mobilomes.Hypomethylated lines were more tolerant when subjected to moderate water deficit and were intrinsically more tolerant to drought-induced cavitation. The alteration of the DDM1 machinery induced variation in DNA methylation in a cytosine context dependent manner, both in genes and transposable elements. Hypomethylated lines subjected to water deficit showed altered expression of genes involved in phytohormone pathways, such as salicylic acid and modified hormonal balance. Several transposable elements showed stress- and/or line-specific patterns of reactivation, and we could detect copy number variations for two of them in stressed ddm1 lines.Overall, our data highlight two major roles for DNA methylation in the shoot apical meristem: control of stress response and plasticity through transduction of hormone signaling and maintenance of genome integrity through the control of transposable elements.


2021 ◽  
Vol 27 (2) ◽  
pp. 227-237
Author(s):  
Haroon Khan

Field surveys were carried out to assess the phytodiversity, phenology, leaf size, leaf shape, life form and ethnobotany of weed flora of village Sufaid Sung, Peshawar from March 2017 to June 2019. Overall, 95 species have been reported associated with 31 families. Dominant families were Poaceae (22 species), Asteraceae (10 species) followed by Amaranthaceae and Papilionaceae (6 species each), Brassicaceae and Polygonaceae (5 species each), Euphorbiaceae and Solanaceae (4 species), Apiaceae, Caryophyllaceae, Cyperaceae, Malvaceae and Verbenaceae added 2 species, Chenopodiaceae and Convolvulaceae contributed 3 species, Apiaceae, Caryophyllaceae, Cyperaceae, Malvaceae and Verbenaceae added 2 species while the rest of 16 families contributed a single species each. The dominant life form was therophytes (76 species) followed by hemicryptophytes (11 species) and geophytes (8 species). Leaf size of the flora showed that the most dominant leaf size class was mesophyll (38 species) followed by macrophyll and microphyll (18 species each), nanopohyll (15 species) and leptophyll (5 species) while a single aphyllous. Simple leaf species were 68 while 26 species had dissected leaves. This study shows a detailed phytodiversical situation of weeds that may be important as reference work for future ethnobotanical, ecological, weed management and conservational studies.


2021 ◽  
Vol 1 (2) ◽  
pp. 1-7
Author(s):  
Kavi K. Oza ◽  
Rinku J. Desai ◽  
Vinay M. Raole*

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.


2016 ◽  
Author(s):  
Daniel H. Chitwood ◽  
Wagner C. Otoni

AbstractBACKGROUNDLeaf shape among Passiflora species is spectacularly diverse. Underlying this diversity in leaf shape are profound changes in the patterning of the primary vasculature and laminar outgrowth. Each of these aspects of leaf morphology—vasculature and blade—provides different insights into leaf patterning.RESULTSHere, we morphometrically analyze >3,300 leaves from 40 different Passiflora species collected sequentially across the vine. Each leaf is measured in two different ways: using 1) 15 homologous Procrustes-adjusted landmarks of the vasculature, sinuses, and lobes and 2) Elliptical Fourier Descriptors (EFDs), which quantify the outline of the leaf. The ability of landmarks, EFDs, and both datasets together are compared to determine their relative ability to predict species and node position within the vine. Pairwise correlation of x and y landmark coordinates and EFD harmonic coefficients reveals close associations between traits and insights into the relationship between vasculature and blade patterning.CONCLUSIONSLandmarks, more reflective of the vasculature, and EFDs, more reflective of the blade contour, describe both similar and distinct features of leaf morphology. Landmarks and EFDs vary in ability to predict species identity and node position in the vine and exhibit a correlational structure (both within landmark or EFD traits and between the two data types) revealing constraints between vascular and blade patterning underlying natural variation in leaf morphology among Passiflora species.


2021 ◽  
Vol 8 (11) ◽  
Author(s):  
Haibin Hang ◽  
Martin Bauer ◽  
Washington Mio ◽  
Luke Mander

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.


2003 ◽  
Vol 19 (3) ◽  
pp. 251-259 ◽  
Author(s):  
Julio V. Schneider ◽  
Daniela Zipp ◽  
Juan Gaviria ◽  
Georg Zizka

Changes in morphological and anatomical leaf characteristics of woody plant species along an altitudinal gradient as well as between a late-successional and mature upper montane rain forest were examined. For leaf size, the Raunkiaer-Webb classification system was applied. The mature-forest transect comprised eight plots of 0.1 ha between 2300 and 3300 m asl, the successional-forest transect, four plots between 2400 and 2750 m asl. The latter comprised structurally heterogeneous vegetation patches. For each plot the proportions of leaf size classes and of the different categories of leaf shape, margin, and apex were calculated. Leaf size and the proportion of drip-tips decreased with increasing elevation. Serrate leaf margins were more prominent at higher elevations. Stomatal density, leaf thickness and related anatomical characteristics did not show significant trends. Differences between the mature and successional forest plots were generally slight. The advanced age of the successional forest probably led to a convergent development of leaf characteristics.


Sign in / Sign up

Export Citation Format

Share Document