Phenotypic variation of Chinese aspens and their relationships to similar taxa in Europe and North America

Morphological variation of leaves and pubescence of buds and shoots from Chinese aspen taxa (sect. Populus of Populus) were studied and compared with those of North American aspens. Data were analyzed for 648 clones from 19 Provinces of Chinese aspen taxa identified on herbarium specimens as P. bonatii Gomb., P. davidiana Dode, P. rotundifolia Griff. var. bonatii Gomb., P. rotundifolia Griff. var. duclouxiana (Dode) Gomb., and P. tremula L. In addition, data from field collections of intact shoots of 137 clones of P. davidiana (Heilongjiang, Jilin, and Shaanxi Provinces) and from 821 clones of P. tremula from Europe were also analyzed. Leaf morphology of herbarium specimens identified as P. davidiana, the most widely distributed Chinese taxon, varied markedly among populations, especially between northern and southwestern China. Clones of P. davidiana from northern and northwestern China were markedly different from those of the P. rotundifolia complex of southwestern China. However, clones identified as P. davidiana from southwestern China were similar to those of P. rotundifolia in leaf shape, number of teeth, and pubescence; they differed only in leaf size. Striking within- and among-population differences were found for field collections of P. davidiana in northeast China. Buds and seasonally determinate shoots of P. davidiana were glabrous in northeast and north-central China; pubescence increased markedly to the southwest. Buds and shoots of clones of the P. rotundifolia complex and P. tremula were predominantly pubescent. The Eurasian aspen taxa are enormously polymorphic in leaf morphology and pubescence; clinal variation along geographic gradients in China, Japan, and Europe are pronounced. Based on studies to date, we would tend to recognize P. davidiana and P. rotundifolia as races of P. tremula. It may be that in all of Eurasia there is but a single, highly polymorphic species, viz. P. tremula. Key words: aspens, China, Eurasia, Populus, morphology, systematics.

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Identification of Vietnamese Paphiopedilum Species Using Vegetative Morphology

Annual Research & Review in Biology ◽

10.9734/arrb/2019/v34i130145 ◽

2020 ◽

pp. 1-14

Author(s):

Huyen- Trang Vu ◽

My-Huyen Bui ◽

Quoc-Luan Vu ◽

Thanh-Diem Nguyen ◽

Hop Tran ◽

...

Keyword(s):

Leaf Morphology ◽

Leaf Shape ◽

Leaf Size ◽

Molecular Methods ◽

Microsoft Excel ◽

Molecular Approaches ◽

The One ◽

Distinct Features ◽

First Time ◽

Efficient Recognition

Background: Discrimination of Paphiopedilum species using floral morphology has been used effectively and commonly due to distinct features of their reproductive parts. Most classification references also focus on description of flower morphology and structure. Nevertheless species preservation meets great problems when illegal trading plants are mostly at non-flowered or plantlet stages. Molecular approaches have been applied and obtained highly precise results but spent time and could not rate 100% of resolution over the genus. Thus, quickly identification using only vegetative characteristics would be an efficient support for other distinguishing methods and a remarkable contribution to the detection and prevention of Paphiopedilum ilicit sales. Aims: In this research we aimed to describe in details leaf features of Paphiopedilum species in Vietnam serving for quick and easy discriminating species without flower present or laboratory techniques. Study Design: Observed variables based on qualitative features of leaf shape, color, vein feature, thickness, toughness and quantitative features of leaf size were saved and organized using Microsoft Excel 2010. Place and Duration of Study: Tay Nguyen Institute for Scientific Research, Agricultural Genetics Institute, between November 2018 and November 2019. Methodology: We minutely analyzed the leaf morphology of nineteen species and two variants which belongs to Vietnamese Paphiopedilum population in an order manner from parameters that easiest to be realized to the less clearly traits for the most efficient recognition even to the one who is not botanist. Results: 16 out of 20 species were identified using leaf morphology. This rate was up to 100% when combining morphological and molecular methods without the present of their flowers. An artificial key to genus Paphiopedilum using the vegetative details was first time established. Conclusion: Leaf morphology can be effectively used as the first step for identifying Paphiopedilum species. Our results provided useful tool in severally or in combination with molecular methods in biodiversity and commercial management of these valuable species.

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Light-induced indeterminacy alters shade avoiding tomato leaf morphology

10.1101/024018 ◽

2015 ◽

Author(s):

Daniel H. Chitwood ◽

Ravi Kumar ◽

Aashish Ranjan ◽

Julie Pelletier ◽

Brad Townsley ◽

...

Keyword(s):

Gene Expression ◽

Leaf Morphology ◽

Meta Analysis ◽

Leaf Shape ◽

Leaf Size ◽

Leaf Primordia ◽

Leaf Mass Per Area ◽

Shade Avoidance ◽

Canonical Pathways ◽

Induced Changes

Plants sense foliar shade of competitors and alter their developmental programs through the shade avoidance response. Internode and petiole elongation, and changes in overall leaf area and leaf mass per area, are the stereotypical architectural responses to foliar shade in the shoot. However, changes in leaf shape and complexity in response to shade remain incompletely, and qualitatively, described. Using a meta-analysis of >18,000 previously published leaflet outlines, we demonstrate that shade avoidance alters leaf shape in domesticated tomato and wild relatives. The effects of shade avoidance on leaf shape are subtle with respect to individual traits, but are combinatorially strong. We then seek to describe the developmental origins of shade-induced changes in leaf shape by swapping plants between light treatments. Leaf size is light-responsive late into development, but patterning events, such as stomatal index, are irrevocably specified earlier. Observing that shade induces increases in shoot apical meristem size, we then describe gene expression changes in early leaf primordia and the meristem using laser microdissection. We find that in leaf primordia shade avoidance is not mediated through canonical pathways described in mature organs, but rather the expression of KNOX and other indeterminacy genes, altering known developmental pathways responsible for patterning leaf shape. We also demonstrate that shade-induced changes in leaf primordium gene expression largely do not overlap with those found in successively initiated leaf primordia, providing evidence against classic hypotheses that shaded leaf morphology results from prolonged production of juvenile leaf types.

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Spatiotemporal variation in leaf size and shape in response to climate

Journal of Plant Ecology ◽

10.1093/jpe/rtz053 ◽

2019 ◽

Vol 13 (1) ◽

pp. 87-96 ◽

Cited By ~ 2

Author(s):

Yaoqi Li ◽

Dongting Zou ◽

Nawal Shrestha ◽

Xiaoting Xu ◽

Qinggang Wang ◽

...

Keyword(s):

Climate Change ◽

Intraspecific Variation ◽

Leaf Shape ◽

Leaf Size ◽

Leaf Length ◽

Herbarium Specimens ◽

Size And Shape ◽

Length Width ◽

Leaf Size And Shape ◽

Over Time

Abstract Aims Morphological variation of leaves is a key indicator of plant response to climatic change. Leaf size and shape are associated with carbon, water and energy exchange of plants with their environment. However, whether and how leaf size and shape responded to climate change over the past decades remains poorly studied. Moreover, many studies have only explored inter- but not intraspecific variation in leaf size and shape across space and time. Methods We collected >6000 herbarium specimens spanning 98 years (1910–2008) in China for seven representative dicot species and measured their leaf length and width. We explored geographical patterns and temporal trends in leaf size (i.e. leaf length, leaf width and length × width product) and shape (i.e. length/width ratio), and investigated the effects of changes in precipitation and temperature over time and space on the variation in leaf size and shape. Important Findings After accounting for the effects of sampling time, leaf size decreased with latitude for all species combined, but the relationship varied among species. Leaf size and shape were positively correlated with temperature and precipitation across space. After accounting for the effects of sampling locations, leaf size of all species combined increased with time. Leaf size changes over time were mostly positively correlated with precipitation, whereas leaf shape changes were mostly correlated with temperature. Overall, our results indicate significant spatial and temporal intraspecific variation in leaf size and shape in response to climate. Our study also demonstrates that herbarium specimens collected over a considerable period of time provide a good resource to study the impacts of climate change on plant morphological traits.

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The Eriochilus dilatatus (Orchidaceae) complex in Western Australia: subspecies taxonomy is not supported by consistent differences in morphology or distribution

Australian Systematic Botany ◽

10.1071/sb19024 ◽

2020 ◽

Author(s):

Mark C. Brundrett ◽

Timothy A. Hammer

Keyword(s):

Western Australia ◽

Leaf Morphology ◽

Habitat Preferences ◽

Leaf Size ◽

Distribution Patterns ◽

Critical Examination ◽

Herbarium Specimens ◽

Taxonomic Confusion ◽

Leaf Size And Shape ◽

Western Australian

A detailed study of taxonomic features of the Eriochilus dilatatus (Orchidaceae) complex (white bunny orchids) in Western Australia found that there were no consistent differences among most subspecies when herbarium specimens or living plants were compared. These subspecies were originally segregated primarily by differences in leaf size and shape and the number of flowers produced, but a critical examination of herbarium specimens found that these features were highly inconsistent within taxa. These features were also found to be highly variable over time and space within populations of living plants. The distribution patterns, habitat preferences and flowering times of these taxa were found to overlap, even for subspecies brevifolius and orientalis, which occupy the northern and eastern limits of the distribution of this species. Eriochilus dilatatus subsp. magnus and subsp. multiflorus were shown to be synonyms of subsp. dilatatus, whereas subsp. undulatus and subsp. orientalis are synonymised under subsp. brevifolius. As a result of this study, the two recognised subspecies are subsp. dilatatus and subsp. brevifolius, which can be readily separated by plant height, flower numbers and leaf morphology, except for a few intermediate plants where ranges overlap. New keys and descriptions to these taxa are provided. The reasons for previous taxonomic confusion in this group and in many other Western Australian orchids are discussed and research approaches to resolve these issues are suggested.

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Leaf shape and size variation in bur oaks: An empirical study and simulation of sampling strategies

10.1101/2020.05.11.088039 ◽

2020 ◽

Author(s):

Sara C Desmond ◽

Mira Garner ◽

Seamus Flannery ◽

Alan T Whittemore ◽

Andrew L Hipp

Keyword(s):

Total Variation ◽

Leaf Morphology ◽

Leaf Shape ◽

Size Variation ◽

Leaf Size ◽

Sampling Strategies ◽

Simulation Code ◽

Individual Tree ◽

Site Variation ◽

Bur Oak

PREMISE: Oaks are notoriously variable in leaf morphology, but little is known regarding the partial contributions of climate, population, latitude, and individual tree to total variation in leaf morphology. This study examines the contributions of within-tree, among-tree, and among-site variation to the total variation in leaf morphology in bur oak (Quercus macrocarpa), one of North America's most geographically widespread oak species. METHODS: Samples were collected from four sites each at northern, central, and southern latitudes of the bur oak range. Ten leaf size traits were measured, and variance in these traits and eight ratios was partitioned into tree, population, and latitude components. We then parameterized a series of leaf collections simulations using empirical covariance among leaves on trees and trees at sites. KEY RESULTS: Leaf size measurements were highly responsive to latitude. Site contributed more than tree to total variation in leaf morphology. Simulations suggest that power to detect among-site variance in leaf morphology can be estimated most efficiently with increases in either leaves per tree (10-11 leaves from each of 5 trees) or trees per site (5 leaves from each of 10+ trees). CONCLUSIONS: Our study demonstrates the utility of both simulating sampling and controlling for variance in sampling for leaf morphology, whether the questions being addressed are ecological, evolutionary, or taxonomic. Simulation code is provided to help researchers plan sampling strategies to maximize the ability to detect among-site variance in leaf morphology.

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Pottery Production, Settlement Patterns and Development of Social Complexity in the Yuanqu Basin, North-Central China

10.30861/9781841719399 ◽

2006 ◽

Cited By ~ 4

Author(s):

Xiangming Dai

Keyword(s):

Settlement Patterns ◽

Social Complexity ◽

Central China ◽

Pottery Production ◽

North Central

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Gemmae in Tetralophozia setiformis (Anastrophyllaceae, Marchantiophyta) and their second record in Eurasia

Novosti sistematiki nizshikh rastenii ◽

10.31111/nsnr/2017.51.242 ◽

2017 ◽

Vol 51 ◽

pp. 242-250

Author(s):

M. V. Dulin

Keyword(s):

British Columbia ◽

Asexual Reproduction ◽

Leaf Shape ◽

Leaf Size ◽

Komi Republic ◽

The Other ◽

Widespread Species ◽

Northern Urals ◽

Sexual And Asexual Reproduction ◽

Murmansk Region

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.

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