scholarly journals Structure and genetic diversity of Theobroma speciosum (Malvaceae) and implications for Brazilian Amazon conservation

Rodriguésia ◽  
2021 ◽  
Vol 72 ◽  
Author(s):  
Juliana de Freitas Encinas Dardengo ◽  
Ana Aparecida Bandini Rossi ◽  
Luiz Orlando de Oliveira ◽  
Guilherme Ferreira Pena ◽  
Luiz Henrique Rivas ◽  
...  

Abstract The genetic diversity of Theobroma speciosum is important because its use in breeding programs, once the species is closely related to species of great economic value such as Theobroma cacao (cocoa) and Theobroma grandiflorum (cupuaçu). Thus, the objective of this work is to characterize the intra and interpopulational genetic diversity of Theobroma speciosum in natural populations in the Brazilian Amazon. Ninety individuals of T. speciosum from four populations localized in different states of legal Amazon were selected and genotyped. The data were obtained by fluorescence microsatellite analysis and the number of alleles, number of private alleles, fixation index, observed and expected heterozygosity were analyzed. Bayesian analysis, AMOVA and PCOa were used to reveal the molecular genetic structure of the populations, using the programs Structure and GenAIEx 6.5, respectively. All populations studied present great levels of gene diversity, although, there was a greater similarity among the AUR, API and MAC populations, while RBC population presented higher heterozygosity and less inbreeding than the others, becoming a possible refuge area in the Amazon, and the most important population for T. speciosum conservation.

Author(s):  
R. H. Sammour ◽  
M. A. Karam ◽  
Y. S. Morsi ◽  
R. M. Ali

Abstract The present study aimed to assess population structure and phylogenetic relationships of nine subspecies of Brassica rapa L. represented with thirty-five accessions cover a wide range of species distribution area using isozyme analysis in order to select more diverse accessions as supplementary resources that can be utilized for improvement of B. napus. Enzyme analysis resulted in detecting 14 putative polymorphic loci with 27 alleles. Mean allele frequency 0.04 (rare alleles) was observed in Cat4A and Cat4B in sub species Oleifera accession CR 2204/79 and in subspecies trilocularis accessions CR 2215/88 and CR 2244/88. The highest genetic diversity measures were observed in subspecies dichotoma, accession CR 1585/96 (the highest average of observed (H0) and expected heterozygosity (He), and number of alleles per locus (Ae)). These observations make this accession valuable genetic resource to be included in breeding programs for the improvement of oilseed B. napus. The average fixation index (F) is significantly higher than zero for the analysis accessions indicating a significant deficiency of heteozygosity. The divergence among subspecies indicated very great genetic differentiation (FST = 0.8972) which means that about 90% of genetic diversity is distributed among subspecies, while 10% of the diversity is distributed within subspecies. This coincides with low value of gene flow (Nm = 0.0287). B. rapa ssp. oleifera (turnip rape) and B. rapa ssp. trilocularis (sarson) were grouped under one cluster which coincides with the morphological classification.


2017 ◽  
Vol 9 (9) ◽  
pp. 13 ◽  
Author(s):  
Walter Okello-Anyanga ◽  
Karin Hansel-Hohl ◽  
Agnes Burg ◽  
Stephan Gaubitzer ◽  
Patrick R. Rubaihayo ◽  
...  

Understanding agricultural biodiversity is critical to formulate breeding strategies for crop improvement and it impacts both, conservation and collection activities. Especially germplasm collections serve as valuable resources, thus, their adequate characterisation is of utmost importance. Although Uganda ranks seventh in African sesame production, meagre research was conducted to determine the current genetic diversity among its germplasm. Therefore, in the present study part of the sesame germplasm conserved at the National Semi-Arid Resources Research Institute (NaSARRI) in Uganda focusing on 85 established lines was genetically and phenotypically characterised. Population genetic and structure analyses revealed rather a low extend of genetic diversity (expected heterozygosity [HE], or gene diversity [D]) ranging from 0 to 0.38 per entry, but a high extend of admixture within and between entries. This decrease of heterozygosity is supported by a fixation index (FST) of 0.530, indicating a medium genetic differentiation among entries. The analysis of quantitative and qualitative agromorphological traits revealed a great inter-trait variability among the entries and further indicated a certain conservation of some of the traits reflecting the geographic origin of the analysed entries. Based on both, the genetic and phenotypic characterisation, a selection of 26 superior entries is proposed, which may form a valuable basis both for farmers and breeders.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Grimar Abdiel Perez ◽  
Pumipat Tongyoo ◽  
Julapark Chunwongse ◽  
Hans de Jong ◽  
Anucha Wongpraneekul ◽  
...  

AbstractThis study explored a germplasm collection consisting of 112 Luffa acutangula (ridge gourd) accessions, mainly from Thailand. A total of 2834 SNPs were used to establish population structure and underlying genetic diversity while exploring the fruit characteristics together with genetic information which would help in the selection of parental lines for a breeding program. The study found that the average polymorphism information content value of 0.288 which indicates a moderate genetic diversity for this L. acutangula germplasm. STRUCTURE analysis (ΔK at K = 6) allowed us to group the accessions into six subpopulations that corresponded well with the unrooted phylogenetic tree and principal coordinate analyses. When plotted, the STRUCTURE bars to the area of collection, we observed an admixed genotype from surrounding accessions and a geneflow confirmed by the value of FST = 0.137. AMOVA based on STRUCTURE clustering showed a low 12.83% variation between subpopulations that correspond well with the negative inbreeding coefficient value (FIS =  − 0.092) and low total fixation index (FIT = 0.057). There were distinguishing fruit shapes and length characteristics in specific accessions for each subpopulation. The genetic diversity and different fruit shapes in the L. acutangula germplasm could benefit the ridge gourd breeding programs to meet the demands and needs of consumers, farmers, and vegetable exporters such as increasing the yield of fruit by the fruit width but not by the fruit length to solve the problem of fruit breakage during exportation.


2020 ◽  
Vol 24 (7) ◽  
pp. 747-754
Author(s):  
V. R. Kharzinova ◽  
N. A. Zinovieva

One of the main tasks of genetics and animal breeding is the assessment of genetic diversity and the study of genetic relationships between different breeds and populations using molecular genetic analysis methods. We analysed the polymorphism of microsatellites and the information on the state of genetic diversity and the population structure of local breeds in Russia: the Kemerovo, the Berkshire, the Liven, the Mangalitsa, and the Civilian; in the Republic of Belarus: the Large White and the Black-and-White; and in Ukraine: the White Steppe, as well as commercial breeds of imported origin of domestic reproduction: the Large White, the Landrace, and the Duroc. The materials used for this study were the tissue and DNA samples extracted from 1,194 pigs and DNA of the UNU “Genetic material bank of domestic and wild animal species and birds” of the L.K. Ernst Federal Research Center for Animal Husbandry. Polymorphisms of 10 microsatellites (S0155, S0355, S0386, SW24, SO005, SW72, SW951, S0101, SW240, and SW857) were determined according to the previously developed technique using DNA analyser ABI3130xl. To estimate the allele pool of each population, the average number of alleles (NA), the effective number of alleles (NE ) based on the locus, the rarified allelic richness (AR), the observed (HO ) and expected (HE ) heterozygosity, and the fixation index (FIS) were calculated. The degree of genetic differentiation of the breeds was assessed based on the pairwise values of FST and D. The analysis of the allelic and genetic diversity parameters of the local breeds showed that the maximum and minimum levels of polymorphism were observed in pigs of the Ukrainian White Steppe breed (NA = 6.500, NE = 3.709, and AR = 6.020) and in pigs of the Duroc breed (NA = 4.875, NE = 2.119, and AR = 3.821), respectively. The highest level of genetic diversity was found in the Large White breed of the Republic of Belarus (HO = 0.707 and NE = 0.702). The minimum level of genetic diversity was found in pigs of the imported breeds – the Landrace (HO = 0.459, HE = 0.400) and the Duroc (HO = 0.480, HE = 0.469) – indicating a high selection pressure in these breeds. Based on the results of phylogenetic analysis, the genetic origin of Large White pigs, the breeds, from which the Berkshire pigs originated, and the genetic detachment of the Landrace from the Mangalitsa breeds were revealed. The cluster analysis showed a genetic consolidation of the Black-and-White, the Berkshire, and the Mangalitsa pigs. Additionally, the imported breeds with clustering depending on the origin were characterised by a genetic structure different from that of the other breeds. The information obtained from these studies can serve as a guide for the management and breeding strategies of the pig breeds studied, to allow their better use and conservation.


2019 ◽  
Vol 69 (3) ◽  
pp. 327-347
Author(s):  
Hadiseh Kashiri ◽  
Ali Shabani ◽  
Saeed Gorgin ◽  
Mohamad Rezaei ◽  
Ahmadreza Jabale

Abstract Rutilus caspicus is considered one of the most important bony fish with high economic value in the Caspian Sea. Since the population size of Caspian roach has decreased during recent decades, restocking of the populations is done through releasing hatchery-produced larvae into the wild. In the present study, the genetic diversity of wild and hatchery populations of R. caspicus was investigated using ten microsatellite loci. Also, microsatellite analysis was performed to compare the population structure of Caspian roach over a time frame of about 11 years. Although the allelic and gene diversity of hatchery populations tended to be lower than those of the wild populations, no significant differences in genetic diversity parameters were observed among the wild and hatchery populations. Similar variation levels were noticed among temporal samples of the same population, suggesting temporal stability in the genetic diversity of the wild populations. In most cases, significant departure from the Hardy-Weinberg equilibrium was observed after sequential Bonferroni correction. Results from analysis showed that a captive hatchery population was the most differentiated group. Also, the UPGMA dendrogram showed that the captive population was the most distant group. The stability of genetic composition between the two periods was noticed by the low and non-significant and estimates. The results from this study are anticipated to provide important information for setting up more efficient strategies for the conservation and restocking of R. caspicus.


2019 ◽  
Vol 27 (5) ◽  
pp. 1423-1434
Author(s):  
Claudivane de Sá Teles Oliveira ◽  
Ricardo Franco Cunha Moreira ◽  
Aldeney Andrade Soares Filho ◽  
Soraia Barreto Aguiar Fonteles ◽  
Norma Suely Evangelista-Barreto

Botany ◽  
2013 ◽  
Vol 91 (10) ◽  
pp. 653-661 ◽  
Author(s):  
Anochar Kaewwongwal ◽  
Arunee Jetsadu ◽  
Prakit Somta ◽  
Sompong Chankaew ◽  
Peerasak Srinives

The objective of this research was to determine the genetic diversity and population structure of natural populations of two rare wild species of Asian Vigna (Phaseoleae, Fabaceae), Vigna exilis Tateishi & Maxted and Vigna grandiflora (Prain) Tateishi & Maxted, from Thailand. Employing 21 simple sequence repeat markers, 107 and 85 individuals from seven and five natural populations of V. exilis and V. grandiflora, respectively, were analyzed. In total, the markers detected 196 alleles for V. exilis and 219 alleles for V. grandiflora. Vigna exilis populations showed lower average values in number of alleles, allelic richness, observed heterozygosity, gene diversity, and outcrossing rate than V. grandiflora populations, namely 58.00% versus 114.60%, 51.96% versus 74.80%, 0.02% versus 0.18%, 0.40% versus 0.66%, and 3.24% versus 17.41%, respectively. Pairwise FST among populations demonstrated that V. exilis was much more differentiated than V. grandiflora. Analysis of molecular variance revealed that 41.83% and 15.06% of total variation resided among the populations of V. exilis and V. grandiflora, respectively. Seven and two genetic clusters were detected for V. grandiflora and V. exilis by STRUCTURE analysis. Our findings suggest that different strategies are required for in situ conservation of the two species. All V. exilis populations, or as many as possible, should be conserved to protect genetic resources of this species, while a few V. grandiflora populations can capture the majority of its genetic variation.


2020 ◽  
Vol 2020 (19) ◽  
pp. 45-53
Author(s):  
Kanstantsin V. Homel ◽  
◽  
K. Śliwińska ◽  
Arseni A. Valnisty ◽  
Mikhail E. Nikiforov ◽  
...  

The paper presents data on the assessment of the genetic diversity of five subpopulations of the European bison (Bison bonasus) in Belarus — from the National Park “Belovezhskaya Pushcha”, the National Park “Pripyatsky”, the Osipovichi district (Mogilev area), SEI “Berezinsky Biosphere Reserve” and the Grodno region. In general, the work includes 30 samples of muscle tissue from the collection of Gene bank of wild fauna in SSPA “SPC NAS of Belarus on Bioresources” (Minsk, Belarus). Microsatellites were used as markers to assess genetic diversity, structure, and search for signs of a sharp decline in the size of bison subpopulations in the past. A total of 11 microsatellite markers were used, recommended by the Food and Agriculture Organization of the United Nations for cattle research. The analysis of B. bonasus subpopulation from the NP “Pripyatsky” showed signs of passing through the genetic bottleneck. All studied subpopulations are characterized by a similarly low genetic diversity level in all analyzed indicators (mean number of alleles, allelic diversity, observed and expected heterozygosity). The expected heterozygosity (He) for the three subpopulations from the NP “Belovezhskaya Pushcha”, the NP “Pripyatsky” and from the Osipovichi district ranged from 0.37 to 0.39. For the studied subpopulations, the values of the fixation index were negative. The assessment of the presence of genetic structuring between the subpopulations of bison from the NP “Belovezhskaya Pushcha”, the NP “Pripyatsky” and from the Osipovichi district based on the values of such indexes as Fst and DJost which showed no signs of genetic differentiation, which is also confirmed by principal coordinates analysis (PCoA). The European bison conservation in Belarus has required tremendous efforts in the past. So far, even though the impressively large population size reached in Belarus, B. bonasus status still should not be considered as stable, which is closely linked to aspects of its overall low genetic diversity. Our research confirmed the low genetic variability of Belarusian subpopulations. Therefore, the more extensive research concentrated on identifying genetic diversity is necessary to ensure the beneficial control of gene flow and register a potential correlation of unfavorable gene variants with possible inbreeding depression. These attempts are required to lay the groundwork for the management and protection of the European bison in Belarus.


Author(s):  
Maizura Abu Sin ◽  
Ghizan Saleh ◽  
Nur Ashikin Psyquay Abdullah ◽  
Pedram Kashiani

Genetic diversity and phenotypic superiority are important attributes of parental inbred lines for use in hybrid breeding programs. In this study, genetic diversity among 30 maize (Zea mays L.) inbred lines comprising of 28 introductions from the International Maize and Wheat Improvement Center (CIMMYT), one from Indonesia and a locally developed, were evaluated using 100 simple sequence repeat (SSR) markers, as early screening for potential parents of hybrid varieties. All markers were polymorphic, with a total of 550 unique alleles detected on the 100 loci from the 30 inbred lines. Allelic richness ranged from 2 to 13 per locus, with an average of 5.50 alleles (na). Number of effective alleles (ne) was 3.75 per locus, indicating their high effectiveness in revealing diversity among inbred lines. Average polymorphic information content (PIC) was 0.624, with values ranging from 0.178 to 0.874, indicating high informativeness of the markers. High gene diversity was observed on Chromosomes 8 and 4, with high number of effective alleles, indicating their potential usefulness for QTL analysis. The UPGMA dendrogram constructed identified four heterotic groups within a similarity index of 0.350, indicating that these markers were able to group the inbred lines. The three-dimensional PCoA plot also supports the dendrogram grouping, indicating that these two methods complement each other. Inbred lines in different heterotic groups have originated from different backgrounds and population sources. Information on genetic diversity among the maize inbred lines are useful in developing strategies exploiting heterosis in breeding programs


2021 ◽  
Author(s):  
Malte Conrady ◽  
Christian Lampei ◽  
Oliver Bossdorf ◽  
Walter Durka ◽  
Anna Bucharova

A growing number of restoration projects require large amounts of seeds. As harvesting natural populations cannot cover the demand, wild plants are often propagated in large-scale monocultures. There are concerns that this cultivation process may cause genetic drift and unintended selection, which would alter the genetic properties of the cultivated populations and reduce their genetic diversity. Such changes could reduce the pre-existing adaptation of restored populations, and limit their adaptability to environmental change. We used single nucleotide polymorphism (SNP) markers and a pool-sequencing approach to test for genetic differentiation and changes in gene diversity during cultivation in 19 wild grassland species, comparing the source populations and up to four consecutive cultivation generations grown from these sources. We then linked the magnitudes of genetic changes to the species breeding systems and seed dormancy, to understand the roles of these traits in genetic change. The propagation of native seeds for ecosystem restoration changed the genetic composition of the cultivated generations only moderately. The genetic differentiation we observed as a consequence of cultivation was much lower than the natural genetic differentiation between different source regions, and the propagated generations harbored even higher gene diversity than wild-collected seeds. Genetic change was stronger in self-compatible species, probably as a result of increased outcrossing in the monocultures. Synthesis and applications: Our study indicates that large-scale seed production maintains the genetic integrity of natural populations. Increased genetic diversity may even increase the adaptive potential of propagated seeds, which makes them especially suitable for ecological restoration. However, we have been working with seeds from Germany and Austria, where the seed production is regulated and certified. Whether other seed production systems perform equally well remains to be tested.


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