scholarly journals Patrones de herbivoría en Vassobia breviflora (Solanaceae): variación en el daño foliar y selección natural mediada por herbívoros

2018 ◽  
Vol 66 (4) ◽  
Author(s):  
Mariana Eugenia Valoy ◽  
Mariano Andrés Ordano ◽  
Facundo Gastón Bernacki ◽  
Facundo Xavier Palacio ◽  
Juan Carlos López Acosta ◽  
...  
Keyword(s):  
Natural Selection ◽  
Leaf Area ◽  
Functional Groups ◽  
Plant Traits ◽  
Leaf Length ◽  
Relative Fitness ◽  
Width Ratio ◽  
Foliar Traits ◽  
Damage Type ◽  
The Relationship

Herbivore mediated-selection shapes the evolution of defensive plant traits. Knowledge about the role of herbivores as mediators of selection is scarce and even more if herbivore functional groups are considered. The objectives of this work were (1) to describe the variation in foliar traits between populations and both between and intra-plants within a population, (2) to explore the relationship between the variation in the herbivory level and foliar traits, (3) to determine the relationship between leaf traits and damage patterns and (4) estimate the selection regimes by different herbivore functional groups. We conducted this study in four populations of Vassobia breviflora in northwestern Argentina (Yungas). The foliar traits considered were size, leaf area (af), shape (leaf length / width ratio; laf) and proportion of leaf area removed (pafr) (N = 1582 leaves, 57 plants). The herbivores consumed 15.6 % of the leaf area and 76.8 % of the variation in the pafr occurred at the sub-individual level. The damage pattern was dominated by cutter herbivores (70 %), followed by a dotted herbivory pattern (22 %), mixed 5 % and 1 % miner. Nonlinear selection was detected for laf (γii = -0.180; EE = 0.76; P < 0.05), and correlational selection between the cutter damage and af (γij = -1.297; SE = 0.62; P < 0.05) and between the dotted damage and af (γij = -1.130; SE = 0.76; P < 0.05). Natural selection favored plants with small leaves and high foliar removal and large leaves with less damage and selection against larger leaves with greater damage was detected. In addition, deduced from the relationship between the damage type and the relative fitness, the selection would favor the dotted damage over the cutter one. The plants would resolve the conflict with the herbivores according to the damage type and natural selection would regulate the foliar display as a strategy to deal with the herbivore diversity.

scholarly journals Morphological differentiation across the invasive range in Senecio madagascariensis populations

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Bruno Dematteis ◽  
María S. Ferrucci ◽  
Juan P. Coulleri
Keyword(s):  
Natural Selection ◽  
Leaf Area ◽  
Plant Traits ◽  
Morphological Differentiation ◽  
Dispersal Ability ◽  
Long Distance ◽  
Environmental Pressures ◽  
Plastic Responses ◽  
New Habitats

AbstractInvasive species are characterized by their ability to colonize new habitats and establish populations away from their native range. In this sense, these plants are expected to have plastic responses to adapt to the environmental pressures during the invasion process. Hence, the role of natural selection is essential because it might favor the occurrence of advantageous traits. However, gene flow can counteract natural selection because immigrants introduce genes adapted to different conditions, with these introductions tending to homogenize allelic frequencies. In this work, we explore the effect of natural selection in invasive populations of S. madagascariensis in Argentina. We quantified leaf area, head number, and length of internodes and inflorescence from material spanning 54 years (1962–2016) and then compared between the edge versus established ranges. Our results show differences in all the measured plant traits among the sampled areas. However, only leaf area was statistically significant, which evidences different responses under the same environmental pressures in the areas located in the edge and established ranges. On the other hand, unlike homogeneous areas, the areas characterized by phenotypically diverse individuals were related to higher dispersal ability. In this sense, long-distance dispersal between neighboring areas may have had an important role in the recorded values. Furthermore, the implications of natural selection and founder effect in the invasion of S. madagascariensis are discussed.

scholarly journals Ecological differentiation in Rumex crispus L. natural populations in metal mining areas

2020 ◽  
Author(s):  
Yajing Zhang ◽  
Huaju Yang ◽  
Yue Wang ◽  
Chundong Tang ◽  
Chang'e Liu ◽  
...  
Keyword(s):  
Leaf Area ◽  
Phenotypic Variation ◽  
Metal Pollution ◽  
Toxic Metal ◽  
Root Diameter ◽  
Leaf Length ◽  
Width Ratio ◽  
Phenotypic Traits ◽  
Rumex Crispus

Abstract Background: Variations in phenotypic traits of various plants living in either normal or stressed environments have been well studied, but ecological responses of plants to long-term persistent toxic metal pollution have little been reported. In this study, in order to explore the effects of continuous metal pollution in soil on variation and differentiation in the plants, Rumex crispus L. populations exposed to different levels of long-term persistent toxic metal pollution were studied, and corresponding R. crispus populations that had not been exposed to pollution were used as controls. Results: Six phenotypic traits of R. crispus—root diameter, leaf area, leaf length, leaf width, leaf perimeter, and leaf length-to-width ratio—differed significantly among and within populations. Traits ranked in descending order of coefficient of variation were leaf area, leaf perimeter, root diameter, leaf length, leaf width, leaf length-to-width ratio. The average coefficient of variation was 46%. Phenotypic variation in R. crispus was much greater among populations (92.69%) than within populations (6.55%). The mean phenotypic differentiation coefficient (Vst) of 93.37% indicates that the interpopulation variability was the main source of phenotypic variation in R. crispus. Finally, root diameter was significantly positively correlated with metal factors, but leaf area, leaf length, and leaf aspect ratio were significantly negatively correlated with Pb, Zn, Mn, and Fe contents. Overall, underground growth is superior to aboveground growth in populations that have experienced long-term exposure to toxic metal pollution, and there were phenotypic differences between uncontaminated and contaminated populations. Conclusions: These results indicate that R. crispus adapts to the heterogeneous environment caused by toxic metal pollution through rich phenotypic variation, and ecological differentiation has occurred among different populations.

scholarly journals Probing the aggregated effects of purifying selection per individual on 1,380 medical phenotypes in the UK Biobank

PLoS Genetics ◽  
2021 ◽  
Vol 17 (1) ◽  
pp. e1009337
Author(s):  
Ha My T. Vy ◽  
Daniel M. Jordan ◽  
Daniel J. Balick ◽  
Ron Do
Keyword(s):  
Natural Selection ◽  
Strong Association ◽  
Purifying Selection ◽  
Relative Fitness ◽  
Uk Biobank ◽  
Multiple Test Correction ◽  
Multiple Test ◽  
The Uk ◽  
The Relationship ◽  
Statistical Metrics

Understanding the relationship between natural selection and phenotypic variation has been a long-standing challenge in human population genetics. With the emergence of biobank-scale datasets, along with new statistical metrics to approximate strength of purifying selection at the variant level, it is now possible to correlate a proxy of individual relative fitness with a range of medical phenotypes. We calculated a per-individual deleterious load score by summing the total number of derived alleles per individual after incorporating a weight that approximates strength of purifying selection. We assessed four methods for the weight, including GERP, phyloP, CADD, and fitcons. By quantitatively tracking each of these scores with the site frequency spectrum, we identified phyloP as the most appropriate weight. The phyloP-weighted load score was then calculated across 15,129,142 variants in 335,161 individuals from the UK Biobank and tested for association on 1,380 medical phenotypes. After accounting for multiple test correction, we observed a strong association of the load score amongst coding sites only on 27 traits including body mass, adiposity and metabolic rate. We further observed that the association signals were driven by common variants (derived allele frequency > 5%) with high phyloP score (phyloP > 2). Finally, through permutation analyses, we showed that the load score amongst coding sites had an excess of nominally significant associations on many medical phenotypes. These results suggest a broad impact of deleterious load on medical phenotypes and highlight the deleterious load score as a tool to disentangle the complex relationship between natural selection and medical phenotypes.

scholarly journals Leaf Area and Its Relationship with Leaf Descriptors Elements in Liquidambar styraciflua L.

2018 ◽  
Vol 75 (1) ◽  
pp. 62
Author(s):  
Daniela Sabina POŞTA ◽  
Florin SALA
Keyword(s):  
Leaf Area ◽  
Biological Material ◽  
Leaf Length ◽  
Liquidambar Styraciflua ◽  
Leaf Width ◽  
The Relationship ◽  
Lobe Width

This study aimed at determining the leaf area in Liquidambar styraciflua L. and at characterising the relationship between leaf area and leaf descriptors. The biological material was the species Liquidambar styraciflua L. We determined leaf area in 100 leaves (Figure 1) based on the size of median rib (L), leaf width at higher (W1) and lower (W2) lobe level, and on area constants (KA). The size of elements L, W1 and W2 were found by measuring with a precision of ±0.5 mm. Area constants in the species Liquidambar styraciflua L. were KA1 = 0.63, determined depending on leaf width at upper lobe width (W1), and KA2 = 0.81 in relation to the width W2 of the lower lobes. Between the scanned leaf area (SLA) and measured leaf area (MLA) and leaf descriptors (L, W1 and W2) we identified relations of interdependence statistically ensured: r = 0.960 to r = 0.971 for SLA; r = 0.951 to r = 0.981 for MLA W1, and r = 0.933 to r = 0.972 for MLA W2, respectively. Leaf descriptors L, W1 and W2 had a differentiated contribution in determining SLA and MLA. SLA was influenced by leaf length (L) with higher statistic safety (R2 = 0.963, p << 0.001, F = 1277.2) than leaf width at upper lobe width W1 (R2 = 0.943; p<<0.001; F = 797.7) and leaf width at the extremities of the lower lobes W2 (R2= 0.927, p << 0.001, F = 620.59).

scholarly journals Chemical and morphological diversity among wild populations of Hypericum aviculariifolium Jaub. et Spach subsp. depilatum (Freyn et Bornm.) N. Robson var. depilatum

2020 ◽  
Vol 79 (1) ◽  
pp. 78-86
Author(s):  
Cuneyt Cirak ◽  
Aysel Özcan ◽  
Emine Yurteri ◽  
Dursun Kurt ◽  
Fatih Seyis
Keyword(s):  
Leaf Area ◽  
Morphological Traits ◽  
High Performance ◽  
Morphological Diversity ◽  
Morphological Characterization ◽  
Leaf Length ◽  
Width Ratio ◽  
Wild Populations ◽  
Full Flowering ◽  
Chemical Content

In this study, the chemical and morphological diversity among eleven wild populations of Hypericum aviculariifolium Jaub. et Spach subsp. depilatum (Freyn et Bornm.) N. Robson var. depilatum, an endemic Turkish species was studied. These populations were investigated for their contents of hypericin, pseudohypericin, hyperforin, the chlorogenic, neochlorogenic, caffeic and 2,4-dihydroxybenzoic acids, hyperoside, quercitrin, isoquercitrin, avicularin, 13,118 biapigenin, (+)-catechin and (-)-epicatechin as well as for their morphological traits, including density of leaf light and dark glands, leaf area, leaf length/width ratio and plant height. The top two-thirds of the plants representing thirty individuals was harvested at full flowering from eleven sites and analyzed for the content of bioactive compounds by high-performance liquid chromatography after being dried at room temperature. Morphological characterization of the wild populations was performed on twenty randomly selected individuals from each plant-growing locality. The content of the tested compounds, except for caffeic acid and avicularin, and some morphological traits, namely, the density of leaf translucent glands and black nodules and leaf area varied significantly with the investigated populations. It was observed that hypericin and pseudohypericin contents were connected positively with leaf black nodule density, but negatively with leaf area and the contents of hyperforin, quercitrin and 13,118-biapigenin were correlated positively with leaf translucent gland density. Data presented here could be useful in determining future targets for further wide-ranging studies on this endemic species as well as in identifying superior germplasm in terms of high chemical content.

scholarly journals Are rate and selectivity correlated in iridium-catalysed hydrogen isotope exchange reactions?

2021 ◽  
Author(s):  
Daria S. Timofeeva ◽  
David M Lindsay ◽  
W. J. Kerr ◽  
David James Nelson
Keyword(s):  
Functional Groups ◽  
Hydrogen Isotope ◽  
Isotope Exchange ◽  
Reaction Rate ◽  
Exchange Reactions ◽  
Reaction Selectivity ◽  
Hydrogen Isotope Exchange ◽  
The Relationship

Herein we examine the relationship between reaction rate and reaction selectivity in iridium-catalysed hydrogen isotope exchange (HIE) reactions directed by Lewis basic functional groups. We have recently develped a directing...

scholarly journals Evolution and evolvability: celebrating Darwin 200

2008 ◽  
Vol 5 (1) ◽  
pp. 44-46 ◽  
Author(s):  
John F.Y Brookfield
Keyword(s):  
Genetic Variation ◽  
Natural Selection ◽  
Time Scales ◽  
Evolutionary Change ◽  
Adaptive Mutation ◽  
Genetic Covariances ◽  
The Relationship ◽  
The Way

The concept of ‘evolvability’ is increasingly coming to dominate considerations of evolutionary change. There are, however, a number of different interpretations that have been put on the idea of evolvability, differing in the time scales over which the concept is applied. For some, evolvability characterizes the potential for future adaptive mutation and evolution. Others use evolvability to capture the nature of genetic variation as it exists in populations, particularly in terms of the genetic covariances between traits. In the latter use of the term, the applicability of the idea of evolvability as a measure of population's capacity to respond to natural selection rests on one, but not the only, view of the way in which we should envisage the process of natural selection. Perhaps the most potentially confusing aspects of the concept of evolvability are seen in the relationship between evolvability and robustness.

On the relationship of NDVI with leaf area index in a deciduous forest site

2005 ◽  
Vol 94 (2) ◽  
pp. 244-255 ◽  
Author(s):  
Quan Wang ◽  
Samuel Adiku ◽  
John Tenhunen ◽  
André Granier
Keyword(s):  
Leaf Area Index ◽  
Leaf Area ◽  
Deciduous Forest ◽  
Forest Site ◽  
Area Index ◽  
Relationship Of ◽  
The Relationship

The relationship between facial whorl direction and sidedness in ridden horses

2006 ◽  
Vol 35 ◽  
pp. 247-250
Author(s):  
H. Randle ◽  
E. Elworthy
Keyword(s):  
Natural Selection ◽  
Artificial Selection ◽  
Competitive Ability ◽  
Close Association ◽  
Human Behaviour ◽  
Physical Ability ◽  
Facial Hair ◽  
Selection For ◽  
The Relationship ◽  
The Brain

The influence of Natural Selection on the evolution of the horse (Equus callabus) is minimal due to its close association with humans. Instead Artificial Selection is commonly imposed through selection for features such as a ‘breed standard’ or competitive ability. It has long been considered to be useful if indicators of characteristics such as physical ability could be identified. Kidd (1902) suggested that the hair coverings of animals were closely related to their lifestyle, whether they were active or passive. In 1973 Smith and Gong concluded that hair whorl (trichloglyph) pattern and human behaviour is linked since hair patterning is determined at the same time as the brain develops in the foetus. More recently Grandin et al. (1995), Randle (1998) and Lanier et al. (2001) linked features of facial hair whorls to behaviour and production in cattle. Hair whorl features have also been related to temperament in equines (Randle et al., 2003).

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