scholarly journals Genetic diversity in three colonizing orchids with contrasting mating systems

1997 ◽  
Vol 84 (2) ◽  
pp. 224-232 ◽  
Author(s):  
Mei Sun
Keyword(s):  
Genetic Diversity ◽  
Mating Systems

scholarly journals Maximizing genetic representation in seed collections from populations of self and cross-pollinated banana wild relatives

2021 ◽  
Author(s):  
Simon Kallow ◽  
Bart Panis ◽  
Toan Vu Dang ◽  
Tuong Vu Dang ◽  
Janet Paofa ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Papua New Guinea ◽  
Mating Systems ◽  
Plant Genetic Resources ◽  
New Guinea ◽  
Musa Acuminata ◽  
Wild Relatives ◽  
Ex Situ ◽  
Conservation Targets ◽  
Seed Collections

Background: Conservation of plant genetic resources, including the wild relatives of crops, plays an important and well recognised role in addressing some of the key challenges faced by humanity and the planet including ending hunger and biodiversity loss. However, the genetic diversity and representativeness of ex situ collections, especially that contained in seed collections, is often unknown. This limits meaningful assessments against conservation targets, impairs targeting of future collecting and limits their use. We assessed genetic representation of seed collections compared to source populations for three wild relatives of bananas and plantains. Focal species and sampling regions were Musa acuminata subsp. banksii (Papua New Guinea), M. balbisiana (Viet Nam) and M. maclayi s.l. (Bougainville, Papua New Guinea). We sequenced 445 samples using suites of 16-20 existing and newly developed taxon-specific polymorphic microsatellite markers. Samples of each species were from five populations in a region; 15 leaf samples and 16 seed samples from one infructescence ('bunch') for each population. Results: Allelic richness of seeds compared to populations was 51%, 81% and 93% (M. acuminata, M. balbisiana and M. maclayi respectively). Seed samples represented all common alleles in populations but omitted some rarer alleles. The number of collections required to achieve the 70% target of the Global Strategy for Plant Conservation was species dependent, relating to mating systems. Musa acuminata populations had low heterozygosity and diversity, indicating self-fertilization; many bunches were needed (>15) to represent regional alleles to 70%; over 90% of the alleles from a bunch are included in only two seeds. Musa maclayi was characteristically cross-fertilizing; only three bunches were needed to represent regional alleles; within a bunch, 16 seeds represent alleles. Musa balbisiana, considered cross-fertilized, had low genetic diversity; seeds of four bunches are needed to represent regional alleles; only two seeds represent alleles in a bunch. Conclusions: We demonstrate empirical measurement of representation of genetic material in seeds collections in ex situ conservation towards conservation targets. Species mating systems profoundly affected genetic representation in seed collections and therefore should be a primary consideration to maximize genetic representation. Results are applicable to sampling strategies for other wild species.

scholarly journals The effects of population size on genetic parameters and mating system of sandalwood in Gunung Sewu, Indonesia

2017 ◽  
Vol 20 (2) ◽  
pp. 182
Author(s):  
Yeni Widyana Nurchahyani ◽  
Sapto Indrioko ◽  
Eny Faridah ◽  
Atus Syahbudin
Keyword(s):  
Genetic Diversity ◽  
Population Size ◽  
Mating Systems ◽  
Natural Disturbance ◽  
Isoenzyme Analysis ◽  
Important Species ◽  
Genetic Base ◽  
Root Suckering ◽  
Genetic Drifts ◽  
Population Demographic

We combined feld observations with isoenzyme analysis to compare population demographic and its effects on genetic diversity and mating systems, among six populations of sandalwood in Gunung Sewu, Indonesia, during March to August 2015. This endangered economic-important species was originated from the southeastern parts of Indonesia, but is recently occured as new landraces in Gunung Sewu, Java island. The observed heterozygosity varied from Ho 0.184 to 0.385 in parents, and from Ho 0.083 to 0.348 in offspring levels, based on the degree of clonality and genetic base. Most of genetic variation is distributed within populations, and only 2.7% were presented among populations, that was indicated by the low DST and FST value (HT 0.30; HS 0.276; DST 2.4%; FST 7.98%). A dendrogram indicated a grouping of populations into three clusters. However, there were seemed to be no association between geographical and genetic distance. Genetic depletion occured due to (i) clonality events as result of heavy-exploitation and/or natural disturbance which induced root suckering, (ii) genetic drifts and bottleneck effects, (iii) the founder effects due to parental low diversity, and (iv) the alteration on mating systems to be more inbreeders. Some of the results confrmed a “reproductive assurance prediction” while some others were contradicting this. It seemed that genetic diversity and mating systems are not much affected by population size, but more by the parental heterozygosity and the degree of clonality. Our results emphasized the importance of populations’ genetic base or parental genetic diversity to naturally maintain the genetic and evolutionary processes under equilibrium conditions.

scholarly journals Genetic analysis of Boletus edulis suggests that intra-specific competition may reduce local genetic diversity as a woodland ages

2020 ◽  
Vol 7 (7) ◽  
pp. 200419
Author(s):  
J. I. Hoffman ◽  
R. Nagel ◽  
V. Litzke ◽  
D. A. Wells ◽  
W. Amos
Keyword(s):  
Genetic Diversity ◽  
Mating Systems ◽  
Terrestrial Ecosystems ◽  
Fruiting Bodies ◽  
Microsatellite Genotyping ◽  
Wild Mushrooms ◽  
Geographic Scale ◽  
Boletus Edulis ◽  
Commercially Important ◽  
New Habitats

Ectomycorrhizal fungi are key players in terrestrial ecosystems yet their mating systems and population dynamics remain poorly understood. We investigated the fine-scale relatedness structure and genetic diversity of Boletus edulis , one of the world's most commercially important wild mushrooms. Microsatellite genotyping of fruiting bodies from 14 different sites around Bielefeld in Germany revealed little in the way of population structure over a geographic scale of several kilometres. However, on a more local scale we found evidence for elevated relatedness as well as inbreeding. We also observed a significant negative association between the genetic diversity of fruit and the age of the trees under which they were sampled. Taken together, our results suggest that as genets mature, they compete and potentially create conditions under which further spores struggle to become established. By implication, even though this species is widely picked, propagules remain common enough to create strong competition when new habitats become available.

scholarly journals Maximizing genetic representation in seed collections from populations of self and cross-pollinated banana wild relatives

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Simon Kallow ◽  
Bart Panis ◽  
Dang Toan Vu ◽  
Tuong Dang Vu ◽  
Janet Paofa ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Papua New Guinea ◽  
Mating Systems ◽  
Plant Genetic Resources ◽  
Genetic Material ◽  
New Guinea ◽  
Wild Relatives ◽  
Ex Situ ◽  
Conservation Targets ◽  
Seed Collections

Abstract Background Conservation of plant genetic resources, including the wild relatives of crops, plays an important and well recognised role in addressing some of the key challenges faced by humanity and the planet including ending hunger and biodiversity loss. However, the genetic diversity and representativeness of ex situ collections, especially that contained in seed collections, is often unknown. This limits meaningful assessments against conservation targets, impairs targeting of future collecting and limits their use. We assessed genetic representation of seed collections compared to source populations for three wild relatives of bananas and plantains. Focal species and sampling regions were M. acuminata subsp. banksii (Papua New Guinea), M. balbisiana (Viet Nam) and M. maclayi s.l. (Bougainville, Papua New Guinea). We sequenced 445 samples using suites of 16–20 existing and newly developed taxon-specific polymorphic microsatellite markers. Samples of each species were from five populations in a region; 15 leaf samples from different individuals and 16 seed samples from one infructescence (‘bunch’) were analysed for each population. Results Allelic richness of seeds compared to populations was 51, 81 and 93% (M. acuminata, M. balbisiana and M. maclayi respectively). Seed samples represented all common alleles in populations but omitted some rarer alleles. The number of collections required to achieve the 70% target of the Global Strategy for Plant Conservation was species dependent, relating to mating systems. Musa acuminata populations had low heterozygosity and diversity, indicating self-fertilization; many bunches were needed (> 15) to represent regional alleles to 70%; over 90% of the alleles from a bunch are included in only two seeds. Musa maclayi was characteristically cross-fertilizing; only three bunches were needed to represent regional alleles; within a bunch, 16 seeds represent alleles. Musa balbisiana, considered cross-fertilized, had low genetic diversity; seeds of four bunches are needed to represent regional alleles; only two seeds represent alleles in a bunch. Conclusions We demonstrate empirical measurement of representation of genetic material in seeds collections in ex situ conservation towards conservation targets. Species mating systems profoundly affected genetic representation in seed collections and therefore should be a primary consideration to maximize genetic representation. Results are applicable to sampling strategies for other wild species.

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

2020 ◽  
Vol 129 (4) ◽  
pp. 773-792
Author(s):  
Melissa A Millar ◽  
David J Coates ◽  
Margaret Byrne ◽  
Siegfried L Krauss ◽  
Matthew R Williams ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Genetic Differentiation ◽  
Mating System ◽  
Mating Systems ◽  
Pollen Dispersal ◽  
Floral Display ◽  
Molecular Tools ◽  
Plant Populations ◽  
Southern Plains ◽  
Population Fitness

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.

Microsatellite genetic diversity and mating systems in the columnar cactus Pachycereus pringlei (Cactaceae)

2016 ◽  
Vol 22 ◽  
pp. 1-10 ◽  
Author(s):  
Carina Gutiérrez-Flores ◽  
Francisco Javier García-De León ◽  
José Luis León-de la luz ◽  
Jorge Hugo Cota-Sánchez
Keyword(s):  
Genetic Diversity ◽  
Mating Systems ◽  
Columnar Cactus ◽  
Pachycereus Pringlei

scholarly journals Selfing is the safest sex for Caenorhabditis tropicalis

2020 ◽  
Author(s):  
Luke M. Noble ◽  
John Yuen ◽  
Lewis Stevens ◽  
Nicolas Moya ◽  
Riaad Persaud ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Population Structure ◽  
Convergent Evolution ◽  
Mating Systems ◽  
Outbreeding Depression ◽  
Duplicated Genes ◽  
Gene Drive ◽  
Multiple Gene ◽  
Nuclear Background ◽  
Self Fertilization

AbstractMating 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 gene drive elements, genetically consistent with maternal toxin/zygotic antidote systems. Driver loci harbor novel and duplicated genes, and their activity is modified by mito-nuclear background. Segregating drivers dramatically reduce fitness, and simulations show that selfing limits their spread. Frequent selfing in C. tropicalis may therefore be a strategy to avoid drive-mediated outbreeding depression.

scholarly journals The genetic diversity and reproductive dynamics of sandalwood in Gunung Sewu (Java, Indonesia) in 2012-2019: designing conservation strategies in a continuous versus fragmented landrace

2021 ◽  
Vol 22 (8) ◽  
Author(s):  
Yeni Ratnaningrum ◽  
Sapto Indrioko ◽  
Amellita Karrin ◽  
Aditya Kurniawan ◽  
ANGGI D.C. PUTRI
Keyword(s):  
Genetic Diversity ◽  
Mating Systems ◽  
Seedling Recruitment ◽  
Vegetative State ◽  
Conservation Strategies ◽  
Illegal Logging ◽  
Genetic Base ◽  
Flowering Season ◽  
Over Time ◽  
Degree Of Fragmentation

Abstract. Ratnaningrum YWN, Indrioko S, Karrin A, Kurniawan A, Putri ADC. 2021. The genetic diversity and reproductive dynamics of sandalwood in Gunung Sewu (Java, Indonesia) in 2012-2019: designing conservation strategies in a continuous versus fragmented landrace. Biodiversitas 22: 3219-3229. This research aimed to compare the dynamics of the genetic diversity, mating systems, and reproductive outputs of the most fragmented (Bejiharjo) and continuous (Bleberan) sandalwood landraces in Gunung Sewu in the flowering periods of 2012-2019. Among the different sandalwood landraces found in Gunung Sewu, Bejiharjo has the highest levels of santalol; unfortunately, this landrace also requires the most attention because of heavy habitat fragmentation resulting from overexploitation, urbanization, and cave-tourism activities. Compared with Bejiharjo, Bleberan demonstrated a wider genetic base and greater outcrossing. Mature and flowering individuals in Bejiharjo decreased from 2012 to 2019 as fragmentation increased, particularly in 2019, during which extreme individual reduction due to illegal logging and land conversion was noted. Recent years consisted of more-clonalized stands, as indicated by the finding of fewer distinct genotypes and higher clonality rates. Increases in clonality and narrowing of the genetic base over time increased selfing rates and reduced offspring heterozygosity and seedling recruitment. The dynamics of genetic diversity in Bleberan, which was relatively undisturbed, appeared to be highly affected by fluctuations in the number of parental genetic bases (i.e., flowering parents) in each flowering season. Some parents bore flowers in one flowering season but remained in a vegetative state in the following season. This irregularity of flowering individuals caused fluctuations in actual population size, resulting in a different genetic base, mating system, and reproductive outputs in every season. All six loci (i.e., Dia-1, Dia-2, Est-1, Est-2, Est-3, and Skd-1) examined in Bleberan are polymorphic sites, and no missing alleles were noted in any of the observation years. Est-2 was monomorphic in Bejiharjo, where rare and missing alleles were more apparent, particularly at the seedling level. Genetic differentiation over time was observed between Bejiharjo and Bleberan, and increased fragmentation was noted in Bejiharjo. The migration rate between these two landraces also decreased over time. Focusing on maintaining the reproductive and genetic processes of each population by implementing different strategies based on the genetic base, mating systems, and degree of fragmentation and clonality of the landrace is recommended.

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