Pollen dispersal, pollen immigration, mating and genetic diversity in restoration of the southern plains Banksia

Abstract Evaluation of patterns of pollen dispersal, mating systems, population fitness, genetic diversity and differentiation in restoration and remnant plant populations can be useful in determining how well restoration activities have achieved their objectives. We used molecular tools to assess how well restoration objectives have been met for populations of Banksia media in the biodiversity hotspot of south-west Western Australia. We characterized patterns of pollen dispersal within, and pollen immigration into, two restoration populations. We compared mating system parameters, population fitness via seed weight, genetic diversity and genetic differentiation for restoration and associated reference remnant populations. Different patterns of pollen dispersal were revealed for two restoration sites that differed in floral display, spatial aggregation of founders and co-planted species. Proximity to remnant native vegetation was associated with enhanced immigration and more short-range pollen dispersal when other population variables were constant. Greater seed weights at remnant compared to restoration populations were not related to outcrossing rate. Equivalent mating system and genetic diversity parameters and low to moderate levels of genetic differentiation between restoration and remnant populations suggest pollinator services have been restored in genetically diverse restoration populations of local provenance B. media as early as four years from planting.

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Evaluating restoration outcomes through assessment of pollen dispersal, mating system and genetic diversity

Restoration Ecology ◽

10.1111/rec.13335 ◽

2020 ◽

Author(s):

Melissa A Millar ◽

David J Coates ◽

Margaret Byrne ◽

Siegfried L Krauss ◽

Justin Jonson ◽

...

Keyword(s):

Genetic Diversity ◽

Mating System ◽

Pollen Dispersal

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Genetic Diversity, Mating System and Systematic Relationships in Two Red Mahoganies, Eucalyptus pellita and E. scias

Australian Journal of Botany ◽

10.1071/bt9960157 ◽

1996 ◽

Vol 44 (2) ◽

pp. 157 ◽

Cited By ~ 14

Author(s):

APN House ◽

JC Bell

Keyword(s):

Genetic Diversity ◽

Genetic Differentiation ◽

Mating System ◽

Papua New Guinea ◽

Isozyme Variation ◽

Irian Jaya ◽

Eucalyptus Pellita ◽

Allelic Differences ◽

Cape York ◽

Systematic Relationships

Isozyme variation in two closely related red mahoganies (Eucalyptus pellita F. Muell. and E. scias L.A.S.Johnson and K.D.Hill) was examined in 17 populations of E. pellita from Australia, Papua New Guinea and Indonesia and 8 of E. scias (including all 3 subspecies) from south-eastern coastal Australia. Measures of genetic diversity and relationships between species and subspecies were based on 15 variable loci. Both E. pellita and E. scias had moderately high levels of genetic diversity, comparable to other similarly distributed species. Most genetic diversity within each species was found within populations (80% in E. pellita and 83% in E. scias). There were substantial allelic differences between the species at several loci; the populations clustered into groups corresponding to the two species. Yet genetic differentiation between the two species was relatively low, and the three subspecies of E. scias were not well separated. Outcrossing rates in E. pellita are variable, with low rates (<50%) measured in populations from Irian Jaya and Cape York Peninsula, and 73% in a population from northeast Queensland.

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Breeding systems, gene flow and level of genetic differentiation in plant populations

Lankesteriana ◽

10.15517/lank.v3i2.23023 ◽

2016 ◽

Vol 3 (2) ◽

Author(s):

Oscar Rocha

Keyword(s):

Genetic Variation ◽

Gene Flow ◽

Genetic Differentiation ◽

Mating Systems ◽

Title Page ◽

Breeding Systems ◽

Plant Populations

<div class="page" title="Page 1"><div class="layoutArea"><div class="column">Genetic variation and its distribution among plant populations are primarily determined by their breed- ing system and the level of gene flow among them (Bawa et al. 1985, Bawa et al. 1990, Rocha & Aguilar 2001b). It is well known that mating systems influence the amount, as well as the distribution of the genetic variation within and among populations (Wright 1921, Stebbins 1950, 1957, Hamrick et al. 1991). </div></div></div>

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Estimating genetic diversity, mating system and pollen dispersal to inform ex situ conservation of tree Genipa americana L.

Plant Genetic Resources ◽

10.1017/s1479262121000022 ◽

2021 ◽

pp. 1-11

Author(s):

Marília Freitas de Vasconcelos Melo ◽

Alexandre Magno Sebbenn ◽

Bruno Cesar Rossini ◽

Ana Veruska Cruz da Silva Muniz ◽

Carlos Jose Rodrigues ◽

...

Keyword(s):

Genetic Diversity ◽

Mating System ◽

Pollen Dispersal ◽

Ex Situ ◽

Fixation Index ◽

Lower Probability ◽

Dispersal Pattern ◽

Long Distance ◽

Dioecious Species ◽

Seed Collection

Abstract Using microsatellite loci, we assessed the mating system and genetic diversity of the dioecious tropical tree Genipa americana in a natural population (NP) and a progeny test (PT). For NP, we also estimated the paternity correlation within and among fruits and mean pollen dispersal distance. As expected for dioecious species, all offspring originated from outcrossing (t = 1). Mating among relatives (1 − ts) and paternity correlation (rp) were variable among progenies (1 − ts = 0.03–0.19; rp = 0.04–0.40), but greater in NP than in PT. Fixation index (F) was generally significant and lower in adults than in offspring, indicating selection against inbred individuals. Paternity correlation was higher within (0.40) than among (0.26) fruits, indicating a lower effective number of pollen donors (Nep) within (2.5) than among (3.8) fruits. Due to the higher rp in NP, the effective size within progenies (Ne) was lower (2.69) than PT (3.27). The pollen dispersal pattern was strongly leptokurtic, suggesting long-distance pollen dispersal (mean of 179 m). The results show that both populations can be used for seed collection in environmental reforestation programmes; however, considering that PT is structured in maternal progenies, NP is more suitable for seed collection due to the lower probability of mating among related trees.

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Assessing the genetic structure of Oryza glumaepatula populations with isozyme markers

Brazilian Archives of Biology and Technology ◽

10.1590/s1516-89132008000500001 ◽

2008 ◽

Vol 51 (5) ◽

pp. 873-882 ◽

Cited By ~ 4

Author(s):

Elizabeth Ann Veasey ◽

Daruska Cardin ◽

Rainério Meireles Silva ◽

Eduardo de Andrade Bressan ◽

Roland Vencovsky

Keyword(s):

Genetic Diversity ◽

Genetic Structure ◽

Genetic Differentiation ◽

Mating System ◽

Outcrossing Rate ◽

Structure Parameters ◽

Mato Grosso ◽

Isozyme Markers ◽

Self Fertilization ◽

Oryza Glumaepatula

To assess the genetic diversity and genetic structure parameters, nine populations of Oryza glumaepatula from the Amazon biome, four from the Pantanal biome, and one collected at Rio Xingu, Mato Grosso, totaling 14 populations and 333 individuals were studied with isozyme markers. Six loci were evaluated showing a moderate allozyme variability (A = 1.21, P = 20.7%, Ho = 0.005, He = 0.060). The populations from the Pantanal biome showed higher diversity levels than the Amazon biome. High genetic differentiation among the populations, expected for self-fertilizing species, was observed (F ST=0.763), with lower differentiation found among the Pantanal populations (F ST=0.501). The average apparent outcrossing rate was higher for the Pantanal populations (t a = 0.092) than for the Amazonian populations (t a = 0.003), while the average for the 14 populations was 0.047, in accordance with a self-fertilization mating system.

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Genetic diversity of Dactylorhiza incarnata (Orchidaceae) in northern Poland

Acta Societatis Botanicorum Poloniae ◽

10.5586/asbp.3496 ◽

2016 ◽

Vol 85 (2) ◽

Cited By ~ 3

Author(s):

Aleksandra M. Naczk ◽

Igor J. Chybicki ◽

Marek S. Ziętara

Keyword(s):

Genetic Diversity ◽

Gene Flow ◽

Genetic Structure ◽

Genetic Differentiation ◽

Pollen Dispersal ◽

Species Level ◽

Bottleneck Effect ◽

Northern Poland ◽

Habitat Loss And Fragmentation ◽

Population Numbers

The genetic structure of Dactylorhiza incarnata var. incarnata populations is shaped not only by historical events such as recolonization after ice sheet retreat or limited seed and pollen dispersal, but also the bottleneck effect. During the last decade, D. incarnata var. incarnata has also experienced a strong decline in population numbers and sizes, due to habitat loss and fragmentation. In the present research genetic diversity was examined in eight populations located in northern Poland, using six nuclear microsatellites loci. At the species level our results showed a moderate mean level of genetic diversity (A = 4.67; Ae = 2.73; Rs = 4.48; Ho = 0.438; FIS = 0.224), which varied among the studied populations (A: 2.17–3.67; Ae: 1.55–2.69; Rs: 1.31–1.61; Ho: 0.292–0.631; FIS: −0.283–0.340). A considerable overabundance of homozygotes was detected in four populations (FIS within the range of 0.067–0.340), and in the remaining populations an excess of heterozygotes was observed. The average apparent out-crossing rate was also calculated (ta = 0.980), and primarily indicated a tendency to out-cross within the species. Moderate genetic differentiation was found among the studied populations (FST = 0.149; RST = 0.174; p < 0.05). The differentiation of the populations corresponded to relatively low gene flow value (Nm = 0.426) among populations, which amounted to only one migrant every second generation.

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Mixed mating system and variable mating patterns in tropical woody bamboos

BMC Plant Biology ◽

10.1186/s12870-019-2024-3 ◽

2019 ◽

Vol 19 (1) ◽

Author(s):

Ning Xie ◽

Ling-Na Chen ◽

Yu-Ran Dong ◽

Han-Qi Yang

Keyword(s):

Mating System ◽

Mating Systems ◽

Pollen Dispersal ◽

Germplasm Conservation ◽

Paternity Analysis ◽

Mixed Mating ◽

Mixed Mating System ◽

Mating Patterns ◽

Woody Bamboos ◽

Dispersal Distances

Abstract Background So far, little is known in detail about mating systems of woody bamboos. Paternity analysis of offspring improved our understanding of these systems, and contributed to their germplasm conservation and genetic improvement. Results In this study, a paternity analysis of offspring from two consecutive mass or sporadically flowering events of Dendrocalamus membranaceus and D. sinicus were conducted to determine their mating system and pollen dispersal using the program COLONY based on simple sequence repeat (SSR) markers. Two sporadically flowering populations of D. sinicus (C1, C2) obtained relatively high paternity assignments rates (69.0–71.4%). Meanwhile, among three populations of D. membranaceus, the sporadically flowering population A also had much higher paternity assignments rates (56.4%) than mass flowering populations B1(28.6%) and B2 (42.5%). Both D. membranaceus and D. sinicus had mixed mating systems while their mating patterns were variable depending on pollination conditions. The maximum pollen dispersal distances were 90 m and 4378 m for D. membranaceus and D. sinicus populations, respectively, and the mating distances of these two species focused on ranges of ca. 0–50 m and 0–1500 m, respectively. Conclusions These results revealed for the first time variable mating patterns in woody bamboos. This suggests half-sib seeds from the same bamboo clump may have different male parents and it is crucial to clarify genetic origin in woody bamboos’ breeding programs. The results also indicate the importance of pollinators in the mating systems of tropical woody bamboos.

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Selfing is the safest sex for Caenorhabditis tropicalis

eLife ◽

10.7554/elife.62587 ◽

2021 ◽

Vol 10 ◽

Author(s):

Luke M Noble ◽

John Yuen ◽

Lewis Stevens ◽

Nicolas D Moya ◽

Riaad Persaud ◽

...

Keyword(s):

Genetic Diversity ◽

Population Structure ◽

Mating System ◽

Convergent Evolution ◽

Mating Systems ◽

Outbreeding Depression ◽

Duplicated Genes ◽

Global Diversity ◽

Nuclear Background ◽

Self Fertilization

Mating systems have profound effects on genetic diversity and compatibility. The convergent evolution of self-fertilization in three Caenorhabditis species provides a powerful lens to examine causes and consequences of mating system transitions. Among the selfers, C. tropicalis is the least genetically diverse and most afflicted by outbreeding depression. We generated a chromosomal-scale genome for C. tropicalis and surveyed global diversity. Population structure is very strong, and islands of extreme divergence punctuate a genomic background that is highly homogeneous around the globe. Outbreeding depression in the laboratory is caused largely by multiple Medea-like elements, genetically consistent with maternal toxin/zygotic antidote systems. Loci with Medea activity harbor novel and duplicated genes, and their activity is modified by mito-nuclear background. Segregating Medea elements dramatically reduce fitness, and simulations show that selfing limits their spread. Frequent selfing in C. tropicalis may therefore be a strategy to avoid Medea-mediated outbreeding depression.

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