Genetic diversity of mocó cotton (Gossypium hirsutum race marie-galante) from the northeast of Brazil: implications for conservation

Botany ◽  
2010 ◽  
Vol 88 (8) ◽  
pp. 765-773 ◽  
Author(s):  
Ivandilson Pessoa Pinto de Menezes ◽  
Paulo Augusto Vianna Barroso ◽  
Lúcia Vieira Hoffmann ◽  
Valeska Silva Lucena ◽  
Marc Giband
Keyword(s):  
Genetic Diversity ◽  
Gossypium Hirsutum ◽  
Geographic Origin ◽  
Rio Grande ◽  
Ex Situ ◽  
High Genetic Diversity ◽  
Breeding Programs ◽  
Extinction Process ◽  
Total Genetic Diversity ◽  
High Level

Mocó cotton ( Gossypium hirsutum  L. race marie-galante (Watt) Hutch.) is a potential source of valuable alleles for breeding programs, mainly because of its great adaptability to semi-arid conditions. With the aim of quantifying mocó cotton genetic variability, 187 plants collected in the northeast of Brazil were evaluated using 12 microsatellite markers. A total of 62 alleles were amplified, ranging from three to eight polymorphic alleles per locus. Total genetic diversity was high (0.52), and when measured on a per state basis, was of 0.37 on average. The population showed a low level of heterozygozity (HO = 0.16), reflecting a high level of endogamy (FIS = 0.67). Phylogenetic analysis using the neighbor-joining method revealed that plants sampled in different states tended to cluster according to their geographic origin, except for those collected in the states of Paraíba and Rio Grande do Norte, which grouped together. Plants from the state of Piauí formed two groups, one with an apparent allelic contribution from G. barbadense, while the second group of plants was closer to those from the states of Paraíba and Rio Grande do Norte. Despite the high genetic diversity that was observed in the remaining populations, urgent conservation efforts should be undertaken, owing to the high level of endogamy and accelerated extinction process that characterizes these populations. Such efforts should focus on the collection and ex situ maintenance of representative genetic diversity.

High genetic diversity in Chilean populations of wheat yellow rust (Puccinia striiformis f. sp. tritici West.) assessed by RAPD and AFLP

2007 ◽  
Vol 58 (6) ◽  
pp. 525 ◽  
Author(s):  
V. Becerra ◽  
M. Paredes ◽  
R. Madariaga ◽  
H. S. Bariana ◽  
M. Mellado ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Puccinia Striiformis ◽  
Yellow Rust ◽  
Geographic Origin ◽  
Adult Plant ◽  
Frequent Change ◽  
High Genetic Diversity ◽  
Production Area ◽  
Plant Resistance Gene ◽  
High Level

Wheat yellow rust (Puccinia striiformis f. sp. tritici West. PST) is one of the main fungal diseases that causes major yield losses in the central and southern wheat production area of Chile. Chilean plant breeding programs have been using specific resistance genes to control this disease and resistance was frequently lost due to the appearance of new pathotypes of this pathogen. This resulted in a frequent change of wheat cultivars in the country. The objective of this work was to determine the genetic polymorphism among PST samples collected in wheat fields throughout the country, using randomly amplified polymorphic DNA (RAPD), and amplified fragment length polymorphism (AFLP). Twenty-nine PST populations from 5 locations were analysed with 64 RAPD primers and 6 combinations of AFLP primers. The coefficients of similarity (53% for RAPD and 14% for AFLP) indicated that the populations of yellow rust in Chile are highly diverse, in contrast with similar studies performed in other countries. This observation is supported by the virulence spectrum of PST population. This stressed the need to pyramid 2 or more major genes in commercial cultivars. Alternatively, the deployment of adult plant resistance gene combinations should be conducted. AFLP technique was more robust for analysis of the genetic diversity of PST compared with RAPD, because of its reproducibility and high level of polymorphism. The analysis of genetic similarity data among yellow rust populations grouped most of the PST population according to their geographic origin.

scholarly journals Frequent germplasm exchanges drive the high genetic diversity of Chinese-cultivated common apricot germplasm

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Qiuping Zhang ◽  
Diyang Zhang ◽  
Kang Yu ◽  
Jingjing Ji ◽  
Ning Liu ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Genetic Resources ◽  
Crop Breeding ◽  
High Quality ◽  
High Genetic Diversity ◽  
Breeding Programs ◽  
Germplasm Diversity ◽  
High Level ◽  
Modern Breeding ◽  
Chromosome Level

AbstractThe genetic diversity of germplasm is critical for exploring genetic and phenotypic resources and has important implications for crop-breeding sustainability and improvement. However, little is known about the factors that shape and maintain genetic diversity. Here, we assembled a high-quality chromosome-level reference of the Chinese common apricot ‘Yinxiangbai’, and we resequenced 180 apricot accessions that cover four major ecogeographical groups in China and other accessions from occidental countries. We concluded that Chinese-cultivated common apricot germplasms possessed much higher genetic diversity than those cultivated in Western countries. We also detected seven migration events among different apricot groups, where 27% of the genome was identified as being introgressed. Remarkably, we demonstrated that these introgressed regions drove the current high level of germplasm diversity in Chinese-cultivated common apricots by introducing different genes related to distinct phenotypes from different cultivated groups. Our results highlight the consideration that introgressed regions may provide an important reservoir of genetic resources that can be used to sustain modern breeding programs.

scholarly journals Statistical analysis of genetic diversity using faba bean landraces database

2020 ◽  
Vol 12 (3) ◽  
pp. 211-215
Author(s):  
N. Velcheva ◽  
S. Petrova
Keyword(s):  
Genetic Diversity ◽  
Cluster Analysis ◽  
Faba Bean ◽  
Plant Genetic Resources ◽  
Sustainable Use ◽  
Climatic Conditions ◽  
Ex Situ ◽  
Breeding Value ◽  
High Genetic Diversity ◽  
Breeding Programs

Abstract. Evaluation of genetic diversity among landraces could be an invaluable aid related to the sustainable use of ex situ collections. Statistical methods are currently available for analysis of databases from investigation of stored germplasm. Faba bean (Vicia faba L.) is a self-pollinating with high percentage of foreign pollination legume crop with a great importance for food and forage due to its high protein content as well as the important role in soil fertility and nitrogen fixation. The local populations are well adapted to specific agro-climatic conditions in the growing areas and are a rich initial material for the breeding programs. The purpose of this study is to establish the genetic diversity of 21 Bulgarian faba bean landraces by important traits in order to review the current potential of conserved germplasm for its sustainable use. All genotypes, included in the study, are collected from expeditions in the country, recorded in the National Register for Plant Genetic Resources and long term stored at the National Genebank. They are characterized according to the International Faba Bean Descriptors. The cluster analysis results show a high genetic diversity in the collection and the variability of each studied trait is presented. The factor analysis, which complements the cluster analysis, gives a reason to group the genotypes with their features into groups that have a breeding value. Genetic diversity in the studied collection has been identified and some of the landraces could be included in future breeding programs.

scholarly journals Microsatellite genotyping from faeces of Lontra longicaudis from southern Brazil

2009 ◽  
Vol 99 (1) ◽  
pp. 5-11 ◽  
Author(s):  
Laura I. Weber ◽  
Cintia G. Hildebrand ◽  
Anderson Ferreira ◽  
Gustavo Pedarassi ◽  
José A. Levy ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Conservation Status ◽  
Significant Degree ◽  
Southern Brazil ◽  
High Genetic Diversity ◽  
Low Degree ◽  
Faecal Samples ◽  
High Level ◽  
Degree Of Differentiation ◽  
Lontra Longicaudis

A genetic study of the neotropical river otter Lontra longicaudis (Olfers, 1818), which has an unknown conservation status, was carried out at the Taim Ecological Station and the margins of the Vargas stream, Rio Grande do Sul, southern Brazil. Faecal samples were collected, and DNA was extracted using a silica-guanidine method. Five microsatellite loci were amplified using PCR with heterologous primers previously described for Lutra lutra (Linnaeus, 1758). Sixteen faecal samples out of 29 from Taim and 11 out of 14 from Vargas stream margins contained enough DNA for genetic analysis. A total of 49 different alleles were found at both localities, from which 18 were exclusively found in individuals from Taim and 17 were exclusives from Vargas individuals. The most common allele was the same at both locations for three loci (Lut715, Lut733, and Lut818). A high level of genetic diversity was found at both sites (NeTaim=4.1, HoTaim=0.299, HeTaim=0.681; NeVargas=4.9, HoVargas=0.355, HeVargas=0.724), being higher at the Vargas stream site. A high and significant level of heterozygote deficiency was observed at most loci according to the χ2 test. The homogeneity χ2 test (P<0.001) showed that there were significant differences in the allele frequencies between the two locations. Genotyping for more than one locus was possible in 81.5% of samples, from which only 37% were possible to genotype for more than three loci. A low degree of relatedness was found among individuals from Taim (R=0.055±0.310), but an even lower value of relatedness was found at the Vargas site (R= -0.285±0.440). The significant degree of differentiation (I=0.890; F ST=0.059) found between Taim and Vargas individuals suggests that there is more than one population of otters in the southern extreme of Brazil, which probably are associated with the water body systems found in this region, the Mirim and the Caiuvá/Flores/Mangueira Lagoons. The high genetic diversity and low relatedness found at the Vargas stream, lead us to believe that the Vargas stream may be acting as a corridor between these water bodies for otter dispersion.

scholarly journals The genetic legacy of fragmentation and overexploitation in the threatened medicinal African pepper-bark tree, Warburgia salutaris

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Annae M. Senkoro ◽  
Pedro Talhinhas ◽  
Fernanda Simões ◽  
Paula Batista-Santos ◽  
Charlie M. Shackleton ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Habitat Degradation ◽  
Random Mating ◽  
Diversity Management ◽  
Iucn Red List ◽  
Ex Situ ◽  
Management Plans ◽  
Conservation Actions ◽  
Genetic Diversity Management ◽  
High Level

AbstractThe pepper-bark tree (Warburgia salutaris) is one of the most highly valued medicinal plant species worldwide. Native to southern Africa, this species has been extensively harvested for the bark, which is widely used in traditional health practices. Illegal harvesting coupled with habitat degradation has contributed to fragmentation of populations and a severe decline in its distribution. Even though the species is included in the IUCN Red List as Endangered, genetic data that would help conservation efforts and future re-introductions are absent. We therefore developed new molecular markers to understand patterns of genetic diversity, structure, and gene flow of W. salutaris in one of its most important areas of occurrence (Mozambique). In this study, we have shown that, despite fragmentation and overexploitation, this species maintains a relatively high level of genetic diversity supporting the existence of random mating. Two genetic groups were found corresponding to the northern and southern locations. Our study suggests that, if local extinctions occurred in Mozambique, the pepper-bark tree persisted in sufficient numbers to retain a large proportion of genetic diversity. Management plans should concentrate on maintaining this high level of genetic variability through both in and ex-situ conservation actions.

scholarly journals Genetic Diversity Studies in MAGIC Population of Soybean (Glycine max (L.) Merrill) Based on Mahalanobis D2 Distance

2021 ◽  
pp. 18-25
Author(s):  
Bidush Ranjan Swar ◽  
V. Swarnalatha ◽  
M. Rajendar Reddy ◽  
S. Vanisree
Keyword(s):  
Genetic Diversity ◽  
Seed Weight ◽  
Quantitative Traits ◽  
Genetic Recombination ◽  
Breeding Programs ◽  
Total Genetic Diversity ◽  
Glycine Max L ◽  
Diversity Studies ◽  
100 Seed Weight ◽  
Number Of Branches

Soybean MAGIC lines are highly variable breeding material which utilizes both recent and historic genetic recombination events. Present investigation was carried out to assess the genetic diversity present among 95 soybean MAGIC lines along with six checks for 10 different quantitative traits. All the genotypes were grouped into 16 clusters by performing Tocher’s clustering method using Mahalanobis D2 distance. Cluster I was the largest comprising of 30 genotypes followed by cluster II (23 genotypes), cluster X (15 genotypes) and cluster IX (9 genotypes). The maximum genetic distance (D2) was observed between cluster XI and XV (168.37) followed by cluster III and XV (164.3), cluster X and XV (149.64) as well as between cluster XII and cluster XVI (145.99). The cluster mean for most of the traits were high in cluster I and cluster XVI. Oil content contributed maximum (23.86%) towards total genetic diversity followed by number of pods plant-1 (18.97%), seed yield plant-1 (18.63%), 100 seed weight (11.05%) and number of branches plant-1 (10.16%) traits. The soybean MAGIC lines belong to the cluster XI (6-120) and cluster XV (6-30, 6-31, 6-5) were found to be the most divergent hence can be utilised in the recombination breeding programs to exploit maximum heterosis.

scholarly journals Genome Size: A Novel Predictor of Nut Weight and Nut Size of Walnut Trees

HortScience ◽  
2018 ◽  
Vol 53 (3) ◽  
pp. 275-282 ◽  
Author(s):  
Saadat Sarikhani Khorami ◽  
Kazem Arzani ◽  
Ghasem Karimzadeh ◽  
Abdolali Shojaeiyan ◽  
Wilco Ligterink
Keyword(s):  
Genetic Diversity ◽  
Genome Size ◽  
Plant Genetic Resources ◽  
Kernel Weight ◽  
High Yield ◽  
Phenotypic Analysis ◽  
High Genetic Diversity ◽  
Breeding Programs ◽  
Superior Genotypes ◽  
Southwest Of Iran

Plant genetic diversity is the fundamental of plant-breeding programs to improve desirable characteristics. Hence, evaluation of genetic diversity is the first step in fruit-breeding programs. Accordingly, the current study was carried out to evaluate 25 superior walnut genotypes in respect of phenotypic and cytological characteristics. For this purpose, 560 walnut genotypes in southwest of Iran were evaluated based on UPOV and International Plant Genetic Resources Institute (IPGRI) descriptor. After a 2-year primary evaluation, 25 superior genotypes were selected for future phenotypic and genome size assessment. Flow cytometry was used to estimate genome size of the selected superior genotypes. A high genetic diversity was found in walnut population collected from the southwest of Iran. The selected superior genotypes had high yield, lateral bearing, thin-shell thickness (0.90–1.64 mm), high nut (12.54–19.80 g) and kernel (7.02–9.91 g) weight with light (L) to extra light (EL) kernel color which easily can be removed from the shell. Also, FaBaCh2 genotype turned out to be protogynous being important as a pollinizer cultivar. In addition to extensive phenotypic analysis, genome size was determined. The studied genotypes were diploid (2n = 2x = 32) and varied in genome size from 1.29 (FaBaAv2) to 1.40 pg (FaBaNs12). Correlation analysis showed that lateral bearing, budbreak date, nut size, and weight were the main variables contributing to walnut production. A linear relationship was found between genome size and nut weight (r = 0.527**), kernel weight (r = 0.551**), and nut size index (NSI) (r = 0.487**). Therefore, genome size can be considered as a strong and valuable tool to predict nut and kernel weight and nut size.

scholarly journals Using Random Amplified Polymorphic DNA to Assess Genetic Diversity and Structure of NaturalCalophyllum brasiliense(Clusiaceae) Populations in Riparian Forests

2014 ◽  
Vol 2014 ◽  
pp. 1-8
Author(s):  
Evânia Galvão Mendonça ◽  
Anderson Marcos de Souza ◽  
Fábio de Almeida Vieira ◽  
Regiane Abjaud Estopa ◽  
Cristiane Aparecida Fioravante Reis ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Genetic Variability ◽  
Random Amplified Polymorphic Dna ◽  
Natural Populations ◽  
Rio Grande ◽  
Shannon Index ◽  
High Genetic Diversity ◽  
Family Structures ◽  
Genetic Diversity And Structure ◽  
Kinship Coefficients

The objective of this study was to assess the genetic variability in two natural populations ofCalophyllum brasilienselocated along two different rivers in the state of Minas Gerais, Brazil, using RAPD molecular markers. Eighty-two polymorphic fragments were amplified using 27 primers. The values obtained for Shannon index (I) were 0.513 and 0.530 for the populations located on the margins of the Rio Grande and Rio das Mortes, respectively, demonstrating the high genetic diversity in the studied populations. Nei’s genetic diversity (He) was 0.341 for the Rio Grande population and 0.357 for the Rio das Mortes population. These results were not significantly different between populations and suggest a large proportion of heterozygote individuals within both populations. AMOVA showed that 70.42% of the genetic variability is found within populations and 29.58% is found among populations (ФST=0.2958). The analysis of kinship coefficients detected the existence of family structures in both populations. Average kinship coefficients between neighboring individuals were 0.053 (P<0.001) in Rio das Mortes and 0.040 (P<0.001) in Rio Grande. This could be due to restricted pollen and seed dispersal and the history of anthropogenic disturbance in the area. These factors are likely to contribute to the relatedness observed among these genotypes.

Evaluation of genetic diversity among some commercial cultivars and Iranian wild strains of Agaricus bisporus by microsatellite markers

Botany ◽  
2016 ◽  
Vol 94 (1) ◽  
pp. 9-13 ◽  
Author(s):  
Nader Rokni ◽  
Ebrahim Mohammadi Goltapeh ◽  
Alireza Shafeinia ◽  
Naser Safaie
Keyword(s):  
Genetic Diversity ◽  
Microsatellite Markers ◽  
Agaricus Bisporus ◽  
Breeding Programs ◽  
Banding Patterns ◽  
Commercial Cultivars ◽  
Wild Strains ◽  
Cultivated Mushroom ◽  
High Level ◽  
Promising Source

Agaricus bisporus (Lange) Imbach is the most widely cultivated mushroom in Iran. Lack of diversity in mushroom crops, especially where disease is concerned, creates a crucial risk for the currently grown cultivars. The aim of this study was to assess the genetic diversity among Iranian wild strains and some commercial cultivars by using microsatellite markers. Eighteen codominant microsatellite markers of A. bisporus (AbSSR) were used to distinguish 17 wild and commercial strains. All of the microsatellite markers used in this research gave clear banding patterns, and only one strain remained undistinguished. Among 106 generated alleles, the wild subgroup presented 53 alleles never found both in brown and white commercial cultivars, and 42 alleles never found in commercial brown strains. The dendrogram obtained by UPGMA clustering analysis separated A. bisporus strains into six groups. Based on our results, the high level of genetic diversity among Iranian wild strains, compared with the commercial strains, provides a new and promising source of diversity for A. bisporus breeding programs. To our knowledge this is the first relevant study of biodiversity in native Iranian populations of A. bisporus.

Analysis of genetic diversity within Australian lucerne cultivars and implications for future genetic improvement

2002 ◽  
Vol 53 (6) ◽  
pp. 629 ◽  
Author(s):  
J. M. Musial ◽  
K. E. Basford ◽  
J. A. G. Irwin
Keyword(s):  
Genetic Diversity ◽  
Population Genetic ◽  
Random Amplified Polymorphic Dna ◽  
Population Diversity ◽  
Breeding Programs ◽  
Population Genetic Diversity ◽  
Medicago Sativa L ◽  
Components Analysis ◽  
High Level ◽  
Selection Of

Lucerne (Medicago sativa L.) is autotetraploid, and predominantly allogamous. This complex breeding structure maximises the genetic diversity within lucerne populations making it difficult to genetically discriminate between populations. The objective of this study was to evaluate the level of random genetic diversity within and between a selection of Australian-grown lucerne cultivars, with tetraploid M. falcata included as a possible divergent control source. This diversity was evaluated using random amplified polymorphic DNA (RAPDs). Nineteen plants from each of 10 cultivars were analysed. Using 11 RAPD primers, 96 polymorphic bands were scored as present or absent across the 190 individuals. Genetic similarity estimates (GSEs) of all pair-wise comparisons were calculated from these data. Mean GSEs within cultivars ranged from 0.43 to 0.51. Cultivar Venus (0.43) had the highest level of intra-population genetic diversity and cultivar Sequel HR (0.51) had the lowest level of intra-population genetic diversity. Mean GSEs between cultivars ranged from 0.31 to 0.49, which overlapped with values obtained for within-cultivar GSE, thus not allowing separation of the cultivars. The high level of intra- and inter-population diversity that was detected is most likely due to the breeding of synthetic cultivars using parents derived from a number of diverse sources. Cultivar-specific polymorphisms were only identified in the M. falcata source, which like M. sativa, is outcrossing and autotetraploid. From a cluster analysis and a principal components analysis, it was clear that M. falcata was distinct from the other cultivars. The results indicate that the M. falcata accession tested has not been widely used in Australian lucerne breeding programs, and offers a means of introducing new genetic diversity into the lucerne gene pool. This provides a means of maximising heterozygosity, which is essential to maximising productivity in lucerne.

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