scholarly journals Heterozygous Trees Rebound the Fastest after Felling by Beavers to Positively Affect Arthropod Community Diversity

Forests ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 694
Author(s):  
Faith M. Walker ◽  
Rachel Durben ◽  
Stephen M. Shuster ◽  
Richard L. Lindroth ◽  
Thomas G. Whitham
Keyword(s):  
Genetic Diversity ◽  
Genetic Relatedness ◽  
Castor Canadensis ◽  
High Stress ◽  
Underlying Mechanism ◽  
Community Level ◽  
Community Diversity ◽  
Population Substructure ◽  
Individual Plant ◽  
Arthropod Community

Although genetic diversity within stands of trees is known to have community-level consequences, whether such effects are present at an even finer genetic scale is unknown. We examined the hypothesis that genetic variability (heterozygosity) within an individual plant would affect its dependent community, which adds a new dimension to the importance of genetic diversity. Our study contrasted foliar arthropod community diversity and microsatellite marker-derived measures of genetic diversity of cottonwood (Populus fremontii) trees that had been felled by beavers (Castor canadensis) and were resprouting, relative to adjacent standing, unfelled trees. Three patterns emerged: 1. Productivity (specific leaf area), phytochemical defenses (salicortin), and arthropod community richness, abundance, and diversity were positively correlated with the heterozygosity of individual felled trees, but not with that of unfelled trees; 2. These relationships were not explained by population substructure, genetic relatedness of the trees, or hybridization; 3. The underlying mechanism appears to be that beaver herbivory stimulates increased productivity (i.e., 2× increase from the most homozygous to the most heterozygous tree) that is the greatest in more heterozygous trees. Salicortin defenses in twigs were also expressed at higher concentrations in more heterozygous trees (i.e., 3× increase from the most homozygous to the most heterozygous tree), which suggests that this compound may dissuade further herbivory by beavers, as has been found for other mammalian herbivores. We suggest that high stress to trees as a consequence of felling reveals a heterozygosity–productivity linkage, which in turn is attractive to arthropods. Although experiments are required to demonstrate causality, these results link the genetic diversity of individual trees to community diversity, supporting the hypothesis that interactions among foundation species (beavers and trees) have community-level effects, and underscores the importance of genetic diversity for biodiversity, conservation, and restoration.

scholarly journals Beavers, Bugs and Chemistry: A Mammalian Herbivore Changes Chemistry Composition and Arthropod Communities in Foundation Tree Species

Forests ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 877
Author(s):  
Rachel M. Durben ◽  
Faith M. Walker ◽  
Liza Holeski ◽  
Arthur R. Keith ◽  
Zsuzsi Kovacs ◽  
...  
Keyword(s):  
Tree Species ◽  
Castor Canadensis ◽  
Habitat Type ◽  
Food Preferences ◽  
Woody Species ◽  
Juvenile Growth ◽  
Arthropod Community ◽  
Riparian Ecosystems ◽  
Arthropod Communities ◽  
The Impact

The North American beaver (Castor canadensis Kuhl) and cottonwoods (Populus spp.) are foundation species, the interactions of which define a much larger community and affect a threatened riparian habitat type. Few studies have tested the effect of these interactions on plant chemistry and a diverse arthropod community. We experimentally examined the impact of beaver foraging on riparian communities by first investigating beaver food preferences for one cottonwood species, Fremont cottonwood (P. fremontii S. Watson), compared to other locally available woody species. We next examined the impact of beaver foraging on twig chemistry and arthropod communities in paired samples of felled and unfelled cottonwood species in northern Arizona (P. fremontii) and southwestern Colorado (narrowleaf cottonwood, P. angustifolia James, and Eastern cottonwood, P. deltoides W. Bartram ex Marshall). Four major patterns emerged: (1) In a cafeteria experiment, beavers chose P. fremontii six times more often than other woody native and exotic species. (2) With two cottonwood species, we found that the nitrogen and salicortin concentrations were up to 45% greater and lignin concentration 14% lower in the juvenile resprout growth of felled trees than the juvenile growth on unfelled trees (six of seven analyses were significant for P. fremontii and four of six were significant for P. angustifolia). (3) With two cottonwood species, arthropod community composition on juvenile branches differed significantly between felled and unfelled trees, with up to 38% greater species richness, 114% greater relative abundance and 1282% greater species diversity on felled trees (six of seven analyses with P. fremontii and four of six analyses with P. angustifolia were significant). The above findings indicate that the highest arthropod diversity is achieved in the heterogenous stands of mixed felled and unfelled trees than in stands of cottonwoods, where beavers are not present. These results also indicate that beaver herbivory changes the chemical composition in 10 out of 13 chemical traits in the juvenile growth of two of the three cottonwood species to potentially allow better defense against future beaver herbivory. (4) With P. deltoides, only one of five analyses in chemistry was significant, and none of the four arthropod community analyses were significant, suggesting that this species and its arthropod community responds differently to beaver. Potential reasons for these differences are unknown. Overall, our findings suggest that in addition to their impact on riparian vegetation, other mammals, birds, and aquatic organisms, beavers also may define the arthropod communities of two of three foundation tree species in these riparian ecosystems.

scholarly journals Genetic structure and diversity of the mustard hill coral Porites astreoides along the Florida Keys reef tract

2021 ◽  
Vol 51 (4) ◽  
Author(s):  
Dominique N. Gallery ◽  
Michelle L. Green ◽  
Ilsa B. Kuffner ◽  
Elizabeth A. Lenz ◽  
Lauren T. Toth
Keyword(s):  
Genetic Diversity ◽  
Gene Flow ◽  
Genetic Relatedness ◽  
Florida Keys ◽  
Genetic Population ◽  
High Genetic Diversity ◽  
Western Atlantic ◽  
Porites Astreoides ◽  
Single Well ◽  
Reef Tract

AbstractIncreases in local and global stressors have led to major declines in coral populations throughout the western Atlantic. While abundances of other species have declined, however, the relative abundance of the mustard hill coral, Porites astreoides, has increased. Porites astreoides is relatively resilient to some stressors, and because of its mixed reproductive strategies, its populations often recover quickly following disturbances. The ability for P. astreoides to continue as a potential “winner” in western Atlantic reefs relies on maintaining sufficient genetic variation within populations to support acclimatization and adaptation to current and future environmental change. Without high genetic diversity and gene flow within the population, it would have limited capacity for adaptation and the species’ competitive advantages could be short-lived. In this study, we determined the genetic relatedness of 37 P. astreoides colonies at four shallow reefs along the offshore Florida Keys Reef Tract (FKRT), a region particularly hard-hit by recent disturbances. Using previously designed microsatellite markers, we determined the genetic diversity and connectivity of individuals among and between sites. Our results suggest that the FKRT likely contains a single, well-mixed genetic population of P. astreoides, with high levels of gene flow and evidence for larval migration throughout the region. This suggests that regional populations of P. astreoides likely have a higher chance of maintaining resilience than many other western Atlantic species as they face current and future disturbances.

Genetic diversity assessment of the almond (Prunus dulcis (Mill.) D.A. Webb) traditional germplasm of Algarve, Portugal, using molecular markers

2014 ◽  
Vol 12 (S1) ◽  
pp. S164-S167 ◽  
Author(s):  
Luis Cabrita ◽  
Elena Apostolova ◽  
Alcinda Neves ◽  
António Marreiros ◽  
José Leitão
Keyword(s):  
Genetic Diversity ◽  
Genetic Relatedness ◽  
Prunus Dulcis ◽  
Sequence Repeat ◽  
Regional Office ◽  
Field Collection ◽  
Diversity Assessment ◽  
Major Cluster ◽  
Local Germplasm ◽  
Simple Sequence

In this study, 123 almond (Prunus dulcis (Mill.) D.A. Webb) trees identified among traditional orchards in the Algarve region and 53 trees of the local field collection managed by the regional office of the Portuguese Ministry of Agriculture (DRAALG) were assessed using isozyme, inter-single sequence repeat and simple sequence repeat or microsatellite techniques for the evaluation of genetic diversity and genetic relatedness and identification of new accessions for the field collection. The isozyme analysis allowed the distribution of the 176 plants into 13 different classes of enzyme similarity, while the use of DNA markers increased the distribution of the analysed trees among 140 discriminating DNA patterns. Multiple cases of homonymy and synonymy were identified in the local germplasm. Some traditional varieties, such as Lourencinha, appeared to be relatively homogeneous, while other local denominations, e.g. Galamba, included diverse genotypes. Of the 13 commercial varieties analysed in this study, 11 assembled in one major cluster clearly differentiated from the majority of the local genotypes. These results reinforced the perception that the Algarve traditional germplasm constitutes an important repository of genetic diversity, eventually carrying alleles of high agricultural interest such as the recently identified Phomopsis resistance in the traditional variety Barrinho Grado.

scholarly journals High Genetic Diversity but Absence of Population Structure in Local Chickens of Sri Lanka Inferred by Microsatellite Markers

2021 ◽  
Vol 12 ◽  
Author(s):  
Amali Malshani Samaraweera ◽  
Ranga Liyanage ◽  
Mohamed Nawaz Ibrahim ◽  
Ally Mwai Okeyo ◽  
Jianlin Han ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Sri Lanka ◽  
Microsatellite Markers ◽  
Allelic Diversity ◽  
Genetic Distances ◽  
Population Substructure ◽  
High Genetic Diversity ◽  
Naked Neck ◽  
Local Chicken ◽  
Local Chickens

Local chicken populations belonging to five villages in two geographically separated provinces of Sri Lanka were analyzed using 20 microsatellite markers to determine the genetic diversity of local chickens. Population genetic parameters were estimated separately for five populations based on geographic locations and for eight populations based on phenotypes, such as naked neck, long legged, crested or crown, frizzle feathered, Giriraj, commercial layer, crossbreds, and non-descript chicken. The analysis revealed that there was a high genetic diversity among local chickens with high number of unique alleles, mean number of alleles per locus (MNA), and total number of alleles per locus per population. A total of 185 microsatellite alleles were detected in 192 samples, indicating a high allelic diversity. The MNA ranged from 8.10 (non-descript village chicken) to 3.50 (Giriraj) among phenotypes and from 7.30 (Tabbowa) to 6.50 (Labunoruwa) among village populations. In phenotypic groups, positive inbreeding coefficient (FIS) values indicated the existence of population substructure with evidence of inbreeding. In commercial layers, a high expected heterozygosity He = 0.640 ± 0.042) and a negative FIS were observed. The positive FIS and high He estimates observed in village populations were due to the heterogeneity of samples, owing to free mating facilitated by communal feeding patterns. Highly admixed nature of phenotypes was explained as a result of rearing many phenotypes by households (58%) and interactions of chickens among neighboring households (53%). A weak substructure was evident due to the mating system, which disregarded the phenotypes. Based on genetic distances, crown chickens had the highest distance to other phenotypes, while the highest similarity was observed between non-descript village chickens and naked neck birds. The finding confirms the genetic wealth conserved within the populations as a result of the breeding system commonly practiced by chicken owners. Thus, the existing local chicken populations should be considered as a harbor of gene pool, which can be readily utilized in developing locally adapted and improved chicken breeds in the future.

scholarly journals Genetic diversity, population structure, and effective population size in two yellow bat species in south Texas

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e10348
Author(s):  
Austin S. Chipps ◽  
Amanda M. Hale ◽  
Sara P. Weaver ◽  
Dean A. Williams
Keyword(s):  
Genetic Diversity ◽  
Population Structure ◽  
North America ◽  
Wind Energy ◽  
Population Size ◽  
Effective Population Size ◽  
Microsatellite Loci ◽  
South Texas ◽  
Population Substructure ◽  
Effective Population

There are increasing concerns regarding bat mortality at wind energy facilities, especially as installed capacity continues to grow. In North America, wind energy development has recently expanded into the Lower Rio Grande Valley in south Texas where bat species had not previously been exposed to wind turbines. Our study sought to characterize genetic diversity, population structure, and effective population size in Dasypterus ega and D. intermedius, two tree-roosting yellow bats native to this region and for which little is known about their population biology and seasonal movements. There was no evidence of population substructure in either species. Genetic diversity at mitochondrial and microsatellite loci was lower in these yellow bat taxa than in previously studied migratory tree bat species in North America, which may be due to the non-migratory nature of these species at our study site, the fact that our study site is located at a geographic range end for both taxa, and possibly weak ascertainment bias at microsatellite loci. Historical effective population size (NEF) was large for both species, while current estimates of Ne had upper 95% confidence limits that encompassed infinity. We found evidence of strong mitochondrial differentiation between the two putative subspecies of D. intermedius (D. i. floridanus and D. i. intermedius) which are sympatric in this region of Texas, yet little differentiation using microsatellite loci. We suggest this pattern is due to secondary contact and hybridization and possibly incomplete lineage sorting at microsatellite loci. We also found evidence of some hybridization between D. ega and D. intermedius in this region of Texas. We recommend that our data serve as a starting point for the long-term genetic monitoring of these species in order to better understand the impacts of wind-related mortality on these populations over time.

Seroepidemiology, Antimicrobial Susceptibility and Virulence Characteristics of Clinical Klebsiella pneumoniae Isolates in Mansoura University Hospitals

2021 ◽  
Vol 30 (1) ◽  
pp. 9-18
Author(s):  
Aya H. Elasmer ◽  
Mohammed Y. Ibrahim ◽  
Dina E. Rizk
Keyword(s):  
Genetic Diversity ◽  
Klebsiella Pneumoniae ◽  
Antimicrobial Susceptibility ◽  
Genetic Relatedness ◽  
Diffusion Method ◽  
Serum Resistance ◽  
Beta Lactam ◽  
University Hospitals ◽  
Disk Diffusion Method ◽  
Pathogenic Potential

Background: Klebsiella pneumoniae is one of the crucial causes of nosocomial and community-acquired infections that can result in various infections in human. Objectives: The present study aim to investigate the prevalence of capsular serotypes, antimicrobial susceptibility and virulence characteristics of K. pneumoniae isolated from different Mansoura University Hospitals. Methodology: K. pneumoniae isolates were collected from different clinical sources at Mansoura University Hospitals. The antimicrobial susceptibility to 14 different antibiotics was determined by disk diffusion method. The capsular serotypes were assessed by quelling test. Serum resistance, haemagglutination, biofilm, lipase, protease and lecithinase enzymes production were assessed phenotypically. Moreover, four virulence genes (rmpA, fimH, kfuBC and wabG) were detected by PCR. The genetic relatedness among isolates was investigated using ERIC-PCR molecular typing. Results: Seventy-three isolates were confirmed as K. pneumoniae. The vast majority of isolates demonstrated MDR patterns (72.6%) including a high resistance rate to the beta-lactam antibiotics (ampicillin: 98.6%, amoxicillin-clavulanic acid: 97.26 %, piperacillin: 97.26 %, amoxicillin: 93.15% and cefotaxime: 94.52%). K1 and K2 were the main serotypes found among the isolates, K1 serotype was the predominant (79.45%). It was found that serum resistance was the highest detected virulence factor among isolates (95.9%) and lipase was the lowest detected factor (19.2%). Haemagglutination was detected in 63% of the isolates especially from rectal swab (83.3%) and sputum (72.7%). The biofilm formation was detected mainly among urine and blood isolates. rmpA, fimH, kfuBC and wabG genes were harbored by 20.5%, 92%, 66% and 94.5% of isolates, respectively. ERIC- PCR showed high genetic diversity (100%, typability, Simpson’s index of diversity= 1). Conclusion: The current study revealed the high antibiotic resistance levels, pathogenic potential, and genetic diversity among K. pneumoniae isolated from different clinical sources which is considered a serious health problem that necessitates interventions to control its spread.

scholarly journals Multidrug-Resistant Salmonella enterica Serovar Rissen Clusters Detected in Azores Archipelago, Portugal

2019 ◽  
Vol 2019 ◽  
pp. 1-9 ◽  
Author(s):  
Leonor Silveira ◽  
Miguel Pinto ◽  
Joana Isidro ◽  
Ângela Pista ◽  
Patrícia Themudo ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Salmonella Enterica ◽  
Genetic Relatedness ◽  
Multidrug Resistant ◽  
Reference Laboratory ◽  
Multiple Sources ◽  
Gastrointestinal Infections ◽  
Azores Archipelago ◽  
Starting Point ◽  
Depth Analysis

Gastrointestinal infections caused by nontyphoidal Salmonella (NTS) remain one of the main causes of foodborne illness worldwide. Within the multiple existing Salmonella enterica serovars, the serovar Rissen is rarely reported, particularly as a cause of human salmonellosis. Between 2015 and 2017, the Portuguese National Reference Laboratory of Gastrointestinal Infections observed an increase in the number of clinical cases caused by multidrug-resistant (MDR) S. enterica serovar Rissen, particularly from the Azores archipelago. In the present study, we analyzed by whole genome sequencing (WGS) all clinical, animal, food, and environmental isolates received up to 2017 in the Portuguese Reference Laboratories. As such, through a wgMLST-based gene-by-gene analysis, we aimed to identify potential epidemiological clusters linking clinical and samples from multiple sources, while gaining insight into the genetic diversity of S. enterica serovar Rissen. We also investigated the genetic basis driving the observed multidrug resistance. By integrating 60 novel genomes with all publicly available serovar Rissen genomes, we observed a low degree of genetic diversity within this serovar. Nevertheless, the majority of Portuguese isolates showed high degree of genetic relatedness and a potential link to pork production. An in-depth analysis of these isolates revealed the existence of two major clusters from the Azores archipelago composed of MDR isolates, most of which were resistant to at least five antimicrobials. Considering the well-known spread of MDR between gastrointestinal bacteria, the identification of MDR circulating clones should constitute an alert to public health authorities. Finally, this study constitutes the starting point for the implementation of the “One Health” approach for Salmonella surveillance in Portugal.

Molecular assessment of maize inbred lines (Zea mays L.) Using microsatellite markers

2018 ◽  
Vol 43 (4) ◽  
pp. 533-542
Author(s):  
Maniruzzaman ◽  
MG Azam ◽  
S Islam ◽  
MG Hossain ◽  
MM Rohman
Keyword(s):  
Genetic Diversity ◽  
Plant Breeding ◽  
Genetic Relatedness ◽  
Agricultural Research ◽  
Inbred Lines ◽  
The Other ◽  
Diversity Analysis ◽  
Genetic Diversity Analysis ◽  
Maize Inbred Lines ◽  
Maize Genotypes

Genetic diversity analysis and germplasm characterization are essential steps in plant breeding and molecular markers are proved tool to accomplish. The present study was undertaken at the Molecular Breeding Lab of Plant Breeding Division, Bangladesh Agricultural Research Institute (BARI) to determine the genetic relatedness and molecular characterization of 15 maize inbred lines of BARI. In present study, genetic diversity analysis was performed by using 10 SSR primers to evaluate the polymorphisms, among them six primers showed distinct polymorphism between the maize inbred lines. The maize genotypes E81, E144, E08, E167, E102, E142 and E121 were found more diverged (0.9003) compared to other inbred lines. On the other hand, the lowest genetic distance values (0.1501) were found between the genotype E140 and genotype E80 followed by genotype E126 and genotype E140; genotype E140 and genotype E65; genotype E65 and genotype E80 values were identical (0.4502). The genotypes viz. E81, E144, E08, E167, E102, E142 and E121 were found far away from centroid of the cluster and rest of the genotypes were placed around the centroid. The Principal Coordinate Analysis (PCO) helped to visualize four major clusters and showed that seven maize inbred lines (E81, E58, E08, E167, E102, E142 and E121) were far away from the other genotypes. In conclusion, SSR markers enabled discrimination among accessions and provided valuable information for future use in improvement of these genomic resources.Bangladesh J. Agril. Res. 43(4): 533-542, December 2018

scholarly journals Genetic Diversity of Red Raspberry Varieties throughout the-World

1993 ◽  
Vol 118 (1) ◽  
pp. 119-129 ◽  
Author(s):  
Adam Dale ◽  
Patrick P. Moore ◽  
Ronald J. McNicol ◽  
Thomas M. Sjulin ◽  
Leonid A. Burmistrov
Keyword(s):  
Genetic Diversity ◽  
Genetic Relatedness ◽  
Geographical Origin ◽  
Rubus Idaeus ◽  
Genetic Contribution ◽  
Red Raspberry ◽  
Inbreeding Coefficients ◽  
Breeding Populations ◽  
Distinct Cluster ◽  
The World

Pedigrees of 137 red raspberry (Rubus idaeus L.) varieties released throughout the world since 1960 were used to calculate: 1) the genetic contribution of founding clones to these varieties; 2) genetic relatedness among them; and 3) their inbreeding coefficients. Fifty founding clones contributed to the pedigrees of these varieties with a mean genetic contribution ranging from <0.1% to 21%. Varieties were clustered according to the genetic contribution into groups strongly related to geographical origin. Varieties developed in the former USSR and derived from `Novost Kuzmina' formed a distinct cluster. The remaining varieties were clustered in groups based mainly on whether they were of North American or European origin. Varieties were clustered also on the basis of Wright's coefficient of relationship-a measure of genetic relatedness. Cluster groups were related to their geographical origin and the varieties within the groups could be traced to similar intermediate parents. Inbreeding coefficients ranged from 0.0 to 0.625 and were related, in part, to the numbers of generations of controlled hybridization from common ancestors. The British group, with the largest number of generations of breeding, had a low mean inbreeding coefficient, indicating that inbreeding can be minimized with attention to the mating system. Strategies are suggested for maintaining and increasing the genetic diversity in the world's red raspberry breeding populations.

scholarly journals Genetics-based interactions of foundation species affect community diversity, stability and network structure

2017 ◽  
Vol 284 (1854) ◽  
pp. 20162703 ◽  
Author(s):  
Arthur R. Keith ◽  
Joseph K. Bailey ◽  
Matthew K. Lau ◽  
Thomas G. Whitham
Keyword(s):  
Network Structure ◽  
Experimental Manipulation ◽  
Species Interaction ◽  
Foundation Species ◽  
Interaction Networks ◽  
Community Diversity ◽  
Arthropod Community ◽  
Pemphigus Betae ◽  
In The Wild ◽  
The Stability

We examined the hypothesis that genetics-based interactions between strongly interacting foundation species, the tree Populus angustifolia and the aphid Pemphigus betae , affect arthropod community diversity, stability and species interaction networks of which little is known. In a 2-year experimental manipulation of the tree and its aphid herbivore four major findings emerged: (i) the interactions of these two species determined the composition of an arthropod community of 139 species; (ii) both tree genotype and aphid presence significantly predicted community diversity; (iii) the presence of aphids on genetically susceptible trees increased the stability of arthropod communities across years; and (iv) the experimental removal of aphids affected community network structure (network degree, modularity and tree genotype contribution to modularity). These findings demonstrate that the interactions of foundation species are genetically based, which in turn significantly contributes to community diversity, stability and species interaction networks. These experiments provide an important step in understanding the evolution of Darwin's ‘entangled bank’, a metaphor that characterizes the complexity and interconnectedness of communities in the wild.

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