Genetic diversity

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Eurasia advantage, not genetic diversity: against Ashraf and Galor's "Genetic Diversity" Hypothesis

Eurasia advantage, not genetic diversity: against Ashraf and Galor's "Genetic Diversity" Hypothesis

Finally, back to genetic diversity more concretely, it is far more likely that within a wide range of genetic diversity, our biological evolution has provided us with enough intellectual and physical capacities to go around when it comes to economic development. As such, all human populations, as long as they have a large enough population supported by favorable environment, have all the biological (including genetic) potentials to develop economically: genetic difference only matters on (very) small scales (Zimmerman 2013). 20 For human populations that are large enough (e.g., at the scale of a country), their genetic makeup has not been a key determining factor of economic development. The deeper cause of the enormous variations in economic development across the globe thus does not within our genetics or genetic diversity but elsewhere. Far more plausibly, the chance for development had been foremost constrained by geography before 1500AD (Diamond 1997) and then by bad institutions and other social factors after 1500AD, although geography still matters a great deal by impacting the historical evolution of different institutions (e.g., democracy vs. autocracy) and other social factors such as cultural traits (Jones 1981; North 1990; Easterly and Levine 2003; Rodrik et al. 2004; Acemoglu and Robinson 2012; Hariri 2012; Olsson and Paik 2014; Tang 2011; Tang, Hu and Li n.d.). 21
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Assessment of genetic diversity in Agropyron desertorum accessions using ISSR molecular marker

Assessment of genetic diversity in Agropyron desertorum accessions using ISSR molecular marker

The assessment of genetic diversity is important, not only for crop improvement, but also for efficient man- agement and conservation of germplasm resources. The current study confirmed the importance of molec- ular studies data in detecting genetic variation among genotypes to select diverse parents in order to carry out a new crossing program successfully. We believe that there is a need for molecular marker studies as a com- plementary study to the morphological traits in the field. The primers IS3, IS6, IS7, IS5, IS14, and IS16 were useful for polymorphism study and can be used for the analy- sis of genome and other Agropyron accessions in future research. The grouping of accessions based on cluster analysis and principal coordinate analysis indicated that genetic variations are not in accordance with the geo- graphical distribution of accessions. The greatest value of similarity was observed between accessions G11 and G10 with 0.79, while the least value was G5, G4 and G8 with 0.39. Due to the high diversity between these two groups, they would be considered appropriate partners in crossing programs to obtain high yield and heterosis.
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High genetic diversity of measles virus, World Health Organization European Region, 2005-2006

High genetic diversity of measles virus, World Health Organization European Region, 2005-2006

In contrast, the prevalence of imported genotype D4 and B3 strains considerably increased during 2005–2006. Genotype D4 strains have a vast geographic distribution, and measles outbreaks associated with this genotype have been reported from all continents (5). D4 viruses are still endemic on the Indian subcontinent as well as in East and South Africa (5,27). Although some outbreaks and sporadic cases associated with genotype D4 had been reported from Europe, the corresponding viruses were mostly imported from other continents and differed considerably from the more recent strains (6,11,30). In 2005–2006, genotype D4 was found in 16 of the 27 countries in which MV has been genotyped; most of the corresponding viruses were related to the outbreak in Romania. Roma and Sinti, communities which had mostly low vaccination levels, were involved in the transmission of the Romanian D4 viruses to at least 10 other countries in Europe. The remaining genotype D4–associated cases from Europe (2005–2006) were often epidemiologically linked to the Indian Subcontinent, East Africa, and the Middle East. The high genetic diversity of the corresponding MV variants is characteristic of multiple importation events. The increased frequency of genotype D4 detection during recent years can be explained by the interruption of transmission of most of the indigenous strains, as well the introduction of genotype D4 strains into highly mobile and hard-to-reach populations with low vac- cination levels.
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Plant genetic diversity, irrigation and nutrient cycling in traditional mountain oases of northern Oman

Plant genetic diversity, irrigation and nutrient cycling in traditional mountain oases of northern Oman

Fluxes of nutrients and energy, and genetic diversity in agro-ecosystems are increasingly used as a criterion to assess the effects of management practices on the environment and system’s sustainability. Initial work on nutrient balances for low-input cropping systems in Africa was done by Dutch scientists (Smaling et al., 1993). Recent advances in measurement techniques of trace gases have allowed to refine the methodology for temperate agro-ecosystems and for intensively managed Asian rice (Butterbach-Bahl et al., 2001). Yet little information is available on nutrient fluxes in complex, small scale crop rotations such as practiced in intensively irrigated desert oasis systems of eastern Arabia. This study was conducted to fill this gap of knowledge. The underlying hypothesis was that a diverse germplasm, the avoidance of salinization by an elaborate irrigation system with a well defined amount of leaching, and large surpluses of N, P and K are important characteristics of these millennia-old systems. Materials and methods
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Genetic diversity of new Chinese <i>Cydia pomonella</i> granulovirus isolates

Genetic diversity of new Chinese <i>Cydia pomonella</i> granulovirus isolates

Key Laboratory of Plant Protection Resources and Pest Management of Ministry of Education, Northwest A&F University, Yangling 712100, China E-mail of corresponding author: johannes.jehle@julius-kuehn.de Cydia pomonella granulovirus (CpGV) is an efficient biological agent to control codling moth in pome fruit orchards. Different geographic CpGV isolates orig- inating from Mexiko, Canada and elswhere have been commercialized since 1980s to control CpGV-susceptible and resistant codling moth populations. Five genome groups (termed as group A, B, C, D and E) representing different phylogenetic lineages, were proposed according to analyses of full genome sequences of different CpGV isolates. Isolates from these groups have differing biological activity against different types of CpGV resistance. In the light of re- sistance management, it is important to determine the genetic diversity of natu- rally occurring CpGV isolates.
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Nutritional composition and genetic diversity of Thai Aromatic Rice landraces

Nutritional composition and genetic diversity of Thai Aromatic Rice landraces

(GBSS alleles) (f asahat et al., 2014) or other genes in the rice ge- nome. Clustering of aromatic rice using the ISSR system showed more clarity and effectiveness than the RAPD system, especially re- garding the nutritional composition issue. Average nutritional com- position value from ISSR clustering related closely with the mea- surement data. Our results indicated that the 50 aromatic rice land- races showed both genetic and nutrient diversity; however, genetic diversity remains the cornerstone of crop improvement, providing breeders with options to develop new and improved cultivars with
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Genetic diversity in natural and experimental, subtropical tree communities - kumulative Dissertation

Genetic diversity in natural and experimental, subtropical tree communities - kumulative Dissertation

Methods: In 2010, we set up a field experiment in subtropical China, using four species from the local species pool. Trees were raised from seeds, with seeds from the same mother tree forming a seed family. We established 23 plots containing one or four species (species diversity treatment) and one or four seed families per species (seed family diversity treatment). Tree growth (stem diameter, plant height and crown expansion) and herbivory (percentage leaf loss due to leaf chewers) were monitored annually from 2011 to 2013. Important findings: Tree species richness promoted growth but had no effect on herbivory. In contrast, seed family diversity reduced growth and increased herbivory, but only so in species mixtures. Most of the observed effects were time-dependent, with the largest effect found in 2013. Our results suggest that biodiversity can affect plant performance directly via tree species-species interactions, or, context-dependent, via potential effects on inter-trophic interactions. Two important conclusions should be drawn from our findings. Firstly, in future studies regarding BEF relationships, intraspecific genetic diversity should be given similar weight as species diversity as it has often been neglected and its effects are not well
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OPUS 4 | Genetic diversity and phylogeography of Australian feral cats

OPUS 4 | Genetic diversity and phylogeography of Australian feral cats

populations and isolation of Kaho’olawe in the microsatellite genotype clade is assumed to be attributable to historically low human habitation and no public access since its use as a US Army training ground and bombing range in 1941 (Department of the Navy 1979; Judd 1916; Warren & Aschmann 1993). Low human habitation is assumed to be equatable with few introductions over time and low number of domestic housecats (Dickman 1996; Koch et al. unpublished data; Oliveira et al. 2008; Say et al. 2012). Cat populations on the islands did not originate solely from ship landings by traders or explorers, but also presumably as secondary introductions as human commensals from nearby islands. The recruitment and intermixing of domestic and stray animals into a wild population is well documented (Dickman 1996; Oliveira et al. 2008; Say et al. 2012), which leads to population growth and an increased genetic variation (Dlugosch & Parker 2008; Kolbe et al. 2004). This would be also applicable for Lana’i with relatively high genetic diversity and a high human population size of approximately 3,200 inhabitants and numerous domestic cat owners (US Census 2000, US Department of Commerce). The Tasmanian cat populations were found to group within the Australian mainland cluster possibly representing a recent domestic and stray cat genotype distributed across the Australian mainland. We assume that grouping of O’ahu, Lana’i, Tasmania, French Island, Asia and portions of Dirk Hartog Island individuals into a cluster in the Bayesian assignment approach are based on the intermixing with domestic fancy breed cats. Therefore, is the interpretation of the development of invasive cat populations greatly biased by its introduction history and recent intermixing with domestic cats.
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The relationship between genetic diversity and species diversity – impact of parallel processes in isolated plant populations

The relationship between genetic diversity and species diversity – impact of parallel processes in isolated plant populations

Second, the long life span of the study species (except for the annual Spergula) favors high genetic diversity, also under conditions of restricted gene flow among populations. Perennial species may suffer less negative genetic consequences of habitat isolation or small population size because less generations pass within a given time span. Thus, the effect of drift is reduced and delayed in perennial species (Hartl and Clark, 1989). Moreover perennial species have a lower extinction risk in dynamic landscapes where environmental conditions change temporarily. A longer life span can compensate for e.g. low reproductive success or limited dispersal (Bossuyt and Honnay, 2006). In annual species fluctuating reproductive output can on the one hand be problematic because recruitment depends on successful reproduction of the previous year. On the other hand, in such species seed production via selfing and persistent seed banks are common, both being insurances against low reproductive output in single years (Thompson and Grime, 1979; Coffin and Lauenroth, 1989).
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The effect of board directors from countries with different genetic diversity levels on corporate performance

The effect of board directors from countries with different genetic diversity levels on corporate performance

18 eliminated through first differencing. All the estimations also include year fixed effects, which capture factors that vary over time in a way that is common to all firms. We opt to identify the causal deviation effect on corporate performance. To this end, we are concerned with all three main sources of endogeneity problems: reverse causality, omitted variables, and measurement error. Reverse causality can arise in our regressions if poor performance leads to the decision to diversify the board by injecting directors with a different nationality. Further, and despite the use of numerous control variables and firm fixed effects, our genetic diversity related index of board heterogeneity may erroneously capture other unobserved elements of diversity, thus falsely attributing our findings to genetic diversity per se. Finally, given that our measures of diversity are constructed using estimated scores, some measurement error may be attached to them. 11
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Morphological and Genetic Diversity of Sea Buckthorn (Hippophae rhamnoides L.) in the Karakoram Mountains of Northern Pakistan

Morphological and Genetic Diversity of Sea Buckthorn (Hippophae rhamnoides L.) in the Karakoram Mountains of Northern Pakistan

   Abstract: Sea buckthorn (Hippophae rhamnoides L.) is a dioecious, wind-pollinated shrub growing in Eurasia including the Karakoram Mountains of Pakistan (Gilgit-Baltistan territory). Contrary to the situation in other countries, in Pakistan this species is heavily underutilized. Moreover, a striking diversity of berry colors and shapes in Pakistan raises the question: which varieties might be more suitable for different national and international markets? Therefore, both morphological and genetic diversity of sea buckthorn were studied to characterize and evaluate the present variability, including hypothetically ongoing domestication processes. Overall, 300 sea buckthorn individuals were sampled from eight different populations and classified as wild and supposedly domesticated stands. Dendrometric, fruit and leaf morphometric traits were recorded. Twelve EST-SSRs (expressed sequence tags-simple sequence repeats) markers were used for genotyping. Significant differences in morphological traits were found across populations and between wild and village stands. A significant correlation was found between leaf area and altitude. Twenty-two color shades of berries and 20 dorsal and 15 ventral color shades of leaves were distinguished. Mean genetic diversity was comparatively high (H e = 0.699). In total, three distinct genetic clusters were observed that corresponded to the populations’ geographic locations. Considering high allelic richness and genetic diversity, the Gilgit-Baltistan territory seems to be a promising source for selection of improved germplasm in sea buckthorn.
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Foliose Ulva Species Show Considerable Inter‐Specific Genetic Diversity, Low Intra‐Specific Genetic Variation, and the Rare Occurrence of Inter‐Specific Hybrids in the Wild

Foliose Ulva Species Show Considerable Inter‐Specific Genetic Diversity, Low Intra‐Specific Genetic Variation, and the Rare Occurrence of Inter‐Specific Hybrids in the Wild

which are expected to evolve under different selec- tive pressures (Kelchner 2000). For instance, the 29 Ulva rigida individuals in this study only carried 117 and 36 variant sites in their chloroplast and mito- chondrion, respectively. Given the limited cytoplas- mic genetic variation, we expect that the large growth and metabolic differences between Ulva indi- viduals from the same species (Fort et al. 2019) is probably largely explained by variation in the nuclear genome. Our strategy did not allow for pre- cise characterization of nuclear genome diversity due to limited coverage and high abundances of bacterial DNA. Such characterization of the nuclear genetic diversity of Ulva species and association of possible genetic markers with growth and nutri- tional variation will be an important part of future strain selection efforts. An analysis of the nuclear genome of the Ulva species presented here will require the generation of reference genome(s) for all six species. Indeed, the large genetic variation in the organellar genomes likely indicates a similar genetic variation in the nuclear genome, and SNP analysis should be performed using a reference for each individual species. Future efforts will be needed to generate axenic cultures of all six species, using methods described by (Califano et al. 2018, De Clerck et al. 2018), to avoid DNA contamination from Ulva symbionts (Alsufyani et al. 2020).
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Determination of genetic diversity among wild grown apricots from Sakit valley in Turkey using SRAP markers

Determination of genetic diversity among wild grown apricots from Sakit valley in Turkey using SRAP markers

and genetic diversity and relationships among the accessions were determined using RAPD, ISSR, SRAP and SSR markers. They found high genetic diversity among Turkish apricot cultivars. Y UAN et al. (2007) reported a 72% polymorphism in apricot based on AFLP data. This is comparable to the SRAP based analysis performed in this study. In apricot, the high level of genetic differentiation could be explained by the mating system and by low migration rates. Most fruit trees under cultivation are derived from allogamic wild pro- genitors in which cross-pollination was maintained by self-incom- patibility. Genetically, domestication of fruit trees means changing the reproductive biology by shifting from sexual reproduction (in the wild) to vegetative propagation (M AGHULY et al., 2005).
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Genetic Diversity And Sexual-Dimorphisms Are Important Contributors To The Inflammatory Response Induced By Endotoxin

Genetic Diversity And Sexual-Dimorphisms Are Important Contributors To The Inflammatory Response Induced By Endotoxin

We have shown that gender is a contributing factor in the LPS-induced inflammatory response of B6 mice. Gender-dimorphisms of the inflammatory response appear to be associated with hormonal differences. However, this contribution is dependent on the genetic background, as demonstrated in comparison with A/J mice. Additionally, we found that treatment with sex-steroid modulates LPS-induced mediators of the inflammatory response, such as IL-10 and TNF-α. However, male mice seem to be better responders to such manipulation. Moreover, the effects were dependent on genetic differences. Some mouse strains revealed to be non-responders to changes in the hormonal environment, i.e. IL-10 levels after EST-treatment in DBA2/J and BALBc/J mice, while others showed opposing response, i.e. TNF-α levels of EST- treated A/J and B6 mice. Thus, our data suggests that gender and genetic diversity combine to modulate the response to a particular injury. However, the effects of sex- steroids and the observed gender-differences seem to be independent of sex- chromosomes. We also evaluated effects of hormonal manipulation at the levels of mortality. Androgen depletion is considered a mainstay of gender-related differences and may improve survival. Interestingly, castration protected only A/J mice against LPS. Such protective effects may be secondary to sex-steroid controlled changes in the ratio of pro- vs. anti-inflammatory components of the inflammatory cascade. However, we concluded that protection is dependent on the type of injury and the genetic background. EST-treatment of A/J and B6 males did not improve outcome from endotoxic shock.
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Genetic diversity and plant fitness in Sanguisorba officinalis (Rosaceae) populations supporting an endangered large blue butterfly

Genetic diversity and plant fitness in Sanguisorba officinalis (Rosaceae) populations supporting an endangered large blue butterfly

Independently from their habitat of origin populations were differentiated in both, performance traits and response to defoliation. These differences could not be attributed to population size, plant density, and the level of intra-population genetic diversity. Thus, it is unlikely that genetic drift and inbreeding which may go along with habitat fragmentation account for the observed population differentiation. Plants from small or genetically less diverse population may be particularly vulnerable to environmental stress (e.g. Heschel and Paige, 1995; Pluess and Stoecklin, 2004) as caused by agricultural practice. S. officinalis plants from such populations did not show reduced performance, even though they had been exposed to defoliation. Therefore, habitat fragmentation does not seem to influence plant response to mowing in the study area. Rather, the observed population differentiation is likely due to unknown selection pressures which may be associated with environmental heterogeneity.
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Diversity under threat: connecting genetic diversity and threat mapping to set conservation priorities for Juglans regia L. populations in Central Asia

Diversity under threat: connecting genetic diversity and threat mapping to set conservation priorities for Juglans regia L. populations in Central Asia

priority populations located inside protected areas. More active management is needed to effectively protect these stands from further demographic decline and erosion of their genetic diversity. Assisted natural regeneration could be a valuable management approach to ensure conservation of these stands that are severely threatened in the short term. One priority population in Uzbekistan (Sariosiyo, UZP4) has a small population size and is subject to high threat levels from overexploitation and overgrazing, thus additional enrichment planting with adapted local walnut trees together with temporary livestock exclusion is one of the most critical management measures needed. Establishing livestock exclusion through fencing ( Al-Rowaily et al., 2015 ) has proven an effective and sustainable approach to restore forest cover and promote conservation. Jalilova and Vacik (2012) investigated sustainable management options in Kyrgyzstan and found that local people were not well aware of the effects of uncontrolled grazing on individual forest species, or ignored the existence and extent of the damage; therefore, capacity building and awareness raising campaigns are needed. For one priority population expected to be exposed to minor short and long-term threat levels (Baljuvon, TJP4), natural regeneration seemed sufficient to ensure the long- term maintenance of the stand.
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Consequences of environmental pollution on genetic diversity in populations of the midge Chironomus riparius

Consequences of environmental pollution on genetic diversity in populations of the midge Chironomus riparius

has been shown to be associated with the level of genetic variation within populations (Mitton, 1997). In general, we assume that the long-term survival of populations depends on a sufficient level of genetic variation which enables them to adapt to environmental changes (Frankham, 2005). The loss of genetic variation is associated with inbreeding (Hansson & Westerberg, 2002; Keller & Waller, 2002) which leads to phenotypic expression of previously rare deleterious alleles and thus reduces the fitness within populations also in the short term. Inbreeding depression has often been reported in agricultural stock-breeding as well as in captive breeding programmes for species conservation purposes (Woodworth et al., 2002). While investigations of genetic variation of captive breeding are commonly applied in the latter field (Montgomery et al., 1997), few attempts have been conducted to assess genetic diversity within animal cultures used for toxicological life-cycle bioassays. Inbreeding depression can be more severe under stressful environmental conditions, e.g. salinity, temperature stress or chemical exposure (Armbruster & Reed 2005; Dahlgaard & Hoffmann, 2000; Hauser & Loeschcke 1996; Kristensen et al., 2003). Therefore, high rates of genetic impoverishment in caged test cultures used for exposure assays are likely to influence results of toxicity tests and thus could bias comparability among tests.
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Genetic diversity of Fasciola hepatica in Austria

Genetic diversity of Fasciola hepatica in Austria

The worldwide occurring common liver fluke Fasciola hepatica can infect humans and animals and leads to considerable illness and economic loss annually. The aim of this study was to determine the genetic diversity of F. hepatica in Austria. In total, 31 adult flukes isolated from cattle from various regions in Austria were investigated for their cytochrome oxidase subunit 1 (cox1) and nicotinamide dehydrogenase subunit 1 (nad1) gene sequences. It was shown that Austrian isolates of F. hepatica reveal extensive genetic diversity. To the best of our knowledge, these are the first data on the diversity of F. hepatica in Austria. Keywords Fasciola hepatica . Digenea . Trematoda . Mitochondrial DNA . Haplotype . Genetic diversity . Austria
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Online Appendix to: Eurasia Advantage, not Genetic Diversity: Against Ashraf and Galor's "Genetic Diversity" Hypothesis

Online Appendix to: Eurasia Advantage, not Genetic Diversity: Against Ashraf and Galor's "Genetic Diversity" Hypothesis

worse economic development. We have tested all possible combinations of indicators of genetic diversity and indicators of economic development, and we obtained almost identical results: after controlling for the Eurasia dummy, almost all indicators of genetic diversity lose statistical significance in regres- sions (see Appendicies B, C, D, E, F, and G for details).

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Genetic diversity, biogeography and the morpho-genetic relationship in extant planktonic foraminifera

Genetic diversity, biogeography and the morpho-genetic relationship in extant planktonic foraminifera

Owing to their excellent fossil record, planktonic foraminifera play an important role as proxies for the reconstruction of past oceanic conditions (e.g. Kucera et al. 2005). The chemical signature of their shells records the properties of the ambient seawater, to which a specimen was exposed during the time of biomineralisation of its shell (e.g. Kucera & Schönfeld 2007). Given that every species possesses its distinct ecological adaptations and physiological characteristics, the geochemical composition of the shell consequently varies between separate species (e.g. Hemleben et al. 1989). In order to receive high resolution paleoceanographic reconstructions, a precise taxonomy and an exact knowledge of the level of biological species and their ecological requirements is thus of essential impor- tance. As a consequence, the biological perspective of this enigmatic group of microplank- ton still requires close attention. Especially the number of extant morphospecies that are analyzed in regard to their extent of hidden genetic diversity has to be further increased, to be able to estimate the biological diversity of planktonic foraminifera. So far, cryptic diversity seemed to be prevalent in all morphospecies studied, partly reaching surprisingly high numbers of cryptic species per morphospecies (for a review see: Darling & Wade 2008). However, a morphological differentiation of the cryptic species was so far rarely achieved (Darling et al. 2006; Aurahs et al. 2011), but is indispensable in order to recognize biological species in the sediment assemblages. In addition, the biogeographical distribution patterns of cryptic species require further examination, in order to discover small scale adaptations that would have consequences for the application of foraminifera in micropaleontological studies. Regional endemism of cryptic species has been disco- vered before (e.g. Aurahs et al. 2009b), however, it is not yet known if restricted
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