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1.
Plant Biol (Stuttg) ; 25(5): 703-714, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37096415

ABSTRACT

Populations of heterostylous plant species are ideally composed of equal frequencies of two (distylous) or three (tristylous) morphologically different floral morphs. Intra-morph incompatibility helps to avoid inbreeding and to maintain genetic diversity, supporting plant fitness and long-term viability. Habitat fragmentation can lead to skewed morph ratios and thereby reduce the abundance of compatible mates. This, in turn, can result in a loss of genetic diversity. We tested whether the genetic diversity of heterostylous plants is affected by morph ratio bias using populations of the distylous grassland plant Primula veris in recently fragmented grasslands. We recorded morph frequencies and population sizes in 30 study populations of P. veris on two Estonian islands characterised by different degrees of habitat fragmentation. Examining variation of thousands of single nucleotide polymorphisms (SNPs) and heterostyly-specific genetic markers, we quantified overall and morph-specific genetic diversity and differentiation in these populations. Morph frequencies deviated more in smaller populations. Skewed morph ratios had a negative effect on the genetic diversity of P. veris in more fragmented grasslands. In the populations of better-connected grassland systems, genetic differentiation among S-morphs was higher than among L-morphs. Our study shows that deviations from morph balance are stronger in small populations and have a negative impact on the genetic diversity of the distylous plant P. veris. Together with the direct negative effects of habitat loss and decreased population size on the genetic diversity of plants, morph ratio bias may intensify the process of genetic erosion, thus exacerbating the local extinction of heterostylous species.


Subject(s)
Grassland , Primula , Primula/genetics , Primula/anatomy & histology , Ecosystem , Polymorphism, Single Nucleotide , Flowers/anatomy & histology
2.
Transfus Clin Biol ; 24(4): 404-409, 2017 Nov.
Article in English | MEDLINE | ID: mdl-28668498

ABSTRACT

BACKGROUND: Donating blood in Estonia is non-remunerated and voluntary. Estonian Blood Service system has four independent regional blood centres that are responsible for blood collection, processing, screening and distribution of blood components to hospitals for clinical use. STUDY DESIGN: This research was carried out as a questionnaire survey. A questionnaire was developed to study lapsing first time donors' (FTD) blood donation experience, intention and willingness to donate again. METHODS: A thousand five hundred and forty-six questionnaires were posted to donors who had one successful donation in 2010 and who had not returned to second donation till the year 2012. For data analysis routine statistical methods were used. To evaluate the most appropriate number of classes, based on previous experience and future expectations, latent class analysis was used. RESULTS: There were 453 respondents (29.3%). For the majority of aspects of blood donation experience the emotions were positive. Results of the study suggested that blood collection agencies should intervene to bolster donors' attitudes, perceived control, and identity as a donor during this crucial post-first donation period. CONCLUSION: First blood donation seems to have been a positive experience. Reasons leading to stopping blood donation should be studied further. Establishing a donor registry for Estonia would be essential to keep track of donors.


Subject(s)
Attitude to Health , Blood Donors/psychology , Tissue and Organ Procurement/methods , Adolescent , Adult , Anxiety/etiology , Blood Donors/statistics & numerical data , Emotions , Estonia , Female , Humans , Male , Middle Aged , Personal Satisfaction , Socioeconomic Factors , Surveys and Questionnaires , Volunteers , Young Adult
3.
Heredity (Edinb) ; 112(5): 471-8, 2014 May.
Article in English | MEDLINE | ID: mdl-24253937

ABSTRACT

Understanding the relationship between structural and functional connectivity is essential for successful restoration and conservation management, particularly in intensely managed agricultural landscapes. We evaluated the relationship between structural and functional connectivity of the wetland plant Lychnis flos-cuculi in a fragmented agricultural landscape using landscape genetic and network approaches. First, we studied the effect of structural connectivity, such as geographic distance and various landscape elements (forest, agricultural land, settlements and ditch verges), on gene flow among populations as a measurement of functional connectivity. Second, we examined the effect of structural graph-theoretic connectivity measures on gene flow among populations and on genetic diversity within populations of L. flos-cuculi. Among landscape elements, forests hindered gene flow in L. flos-cuculi, whereas gene flow was independent of geographic distance. Among the structural graph-theoretic connectivity variables, only intrapopulation connectivity, which was based on population size, had a significant positive effect on gene flow, that is, more gene flow took place among larger populations. Unexpectedly, interpopulation connectivity of populations, which takes into account the spatial location and distance among populations, did not influence gene flow in L. flos-cuculi. However, higher observed heterozygosity and lower inbreeding was observed in populations characterised by higher structural interpopulation connectivity. This finding shows that a spatially coherent network of populations is significant for maintaining the genetic diversity of populations. Nevertheless, lack of significant relationships between gene flow and most of the structural connectivity measures suggests that structural connectivity does not necessarily correspond to functional connectivity.


Subject(s)
Gene Flow , Genetic Variation , Grassland , Lychnis/genetics , Agriculture/methods , Algorithms , Conservation of Natural Resources/methods , Genetics, Population , Geography , Heterozygote , Inbreeding , Lychnis/growth & development , Models, Genetic , Population Density , Population Dynamics , Switzerland
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