Exploring genetic diversity of lowland avocado as a genetic reservoir for breeding.

Abstract The avocado (Persea americana Mill.) is highly valued worldwide for its desirable nutritional properties and broader applications in the oil and pharmaceutical industry. Despite northwestern Mexico, with a tropical semi desert climate, is not considered as part of the avocado origin center in Mexico, it possesses a high morphological diversity of avocado fruits. In an effort to provide more information about the diversity present in this region and at the same time, to support a more efficient production of avocado in this climate, this study characterized the genetic diversity of avocado trees growing at northwestern Mexico. Genetic diversity was estimated by using eight microsatellite loci. 45 seed-derived trees, with contrasting fruit morphology were identified. Results showed a high level of genetic diversity with 11.5 alleles per locus, a polymorphic index content of 0.75, and observed and expected heterozygosity values of 0.58 and 0.79, respectively, these values were similar to those observed in germplasm banks and genotypes from centers of origin. Clustering analysis assigned local genotypes to six clusters but did not provide a clear separation among avocado races, suggesting that local genotypes are a result of racial hybridization. Interestingly, avocados from the Mexican race and the commercial variety Hass clustered into two different groups. Despite not being considered a center of origin, results confirm an extensive diversity in northwestern Mexico, encouraging further exploration and preservation of genotypes with desirable traits to future breeding programs for the selection of local genotypes adapted to a lowland tropical climate.

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

Botany ◽

10.1139/cjb-2015-0131 ◽

2016 ◽

Vol 94 (1) ◽

pp. 9-13 ◽

Cited By ~ 6

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.

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

Australian Journal of Agricultural Research ◽

10.1071/ar01178 ◽

2002 ◽

Vol 53 (6) ◽

pp. 629 ◽

Cited By ~ 17

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

Botany ◽

10.1139/b10-045 ◽

2010 ◽

Vol 88 (8) ◽

pp. 765-773 ◽

Cited By ~ 6

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.

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Study genetic diversity in maize inbreds and improved hybrid vigor in hybrids produce to determine commercial hybrids in Iraq

JOURNAL OF ADVANCES IN BIOTECHNOLOGY ◽

10.24297/jbt.v5i3.1542 ◽

2015 ◽

Vol 5 (3) ◽

pp. 728-731

Author(s):

Ziyad A. Abed

Keyword(s):

Genetic Diversity ◽

Genetic Distance ◽

Rapd Markers ◽

Field Experiments ◽

Random Amplified Polymorphic Dna ◽

Hybrid Vigor ◽

Breeding Programs ◽

Genetic Studies ◽

Maize Inbreds ◽

High Level

Â A field experiments was conducted in greenhouse to determinate the genetic diversity among 7 genotypes from maize(4 inbreds and 3hybrids) by using molecular markers with Random Amplified polymorphic DNA(RAPD),that shown high level of polymorphism among genotypes of maize ,where the percentage of polymorphism ranged from(66%) and (83.33%) the highest number of polymorphism band (16) and size fragment ranged between (3800 bp) with the primer ( Bnlg 1185 ) and the lowest 180 with the primer( Bnlg 1464).The genetic distance value ranged between (0.3451) and (0.6534) ,where the lowest genic distance between (k1 and k2),while the highest genetic distance between(k4) and (k3xk4).In this study RAPD markers were shown to be powerful to detect genetic diversity and provided us high polymorphism values within genotypes of maize ,also we can conclude for useful those primers for genetic studies in plant breeding programs for developing synthetic cultivars or improved inbreds of maize.Â

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Genetic Diversity in Colletotrichum gloeosporioides from Stylosanthes spp. at Centers of Origin and Utilization

Phytopathology ◽

10.1094/phyto.2003.93.2.176 ◽

2003 ◽

Vol 93 (2) ◽

pp. 176-185 ◽

Cited By ~ 21

Author(s):

P. L. Weeds ◽

S. Chakraborty ◽

C. D. Fernandes ◽

M. J. d'A. Charchar ◽

C. R. Ramesh ◽

...

Keyword(s):

Genetic Diversity ◽

Colletotrichum Gloeosporioides ◽

Host Population ◽

South American ◽

Pathogen Population ◽

Center Of Origin ◽

China And India ◽

Wild Host ◽

Exotic Pathogen ◽

High Level

Using molecular markers, this work compares the genetic diversity in Colletotrichum gloeosporioides infecting species of the tropical forage legume Stylosanthes at the center of origin in Brazil and Colombia with that of Australia, China, and India, where Stylosanthes spp. have been introduced for commercial use. There was extensive diversity in the pathogen population from Brazil, Colombia, China, and India. The Australian pathogen population was least diverse probably due to its geographical isolation and effective quarantine. The extensive diversity in China and India means that threats from exotic pathogen races to Stylosanthes pastures can potentially come from countries outside the South American center of origin. In Brazil and India, both with native Stylosanthes populations, a high level of genetic differentiation in the pathogen population was associated with sites where native or naturalized host population was widely distributed. There was limited genetic diversity at germplasm evaluation sites, with a large proportion of isolates having identical haplotypes. This contrasts recent pathogenicity results for 78 of the Brazilian isolates that show hot spots of complex races are more common around research stations where host germplasm are tested, but few are found at sites containing wild host populations. For a pathogen in which the same races arise convergently from different genetic backgrounds, this study highlights the importance of using both virulence and selectively neutral markers to understand pathogen population structure.

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

Horticulture Research ◽

10.1038/s41438-021-00650-8 ◽

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.

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Assessment of genetic diversity of Turkish and Algerian native sheep breeds

Acta agriculturae Slovenica ◽

10.14720/aas.2020.115.1.1229 ◽

2020 ◽

Vol 115 (1) ◽

pp. 5

Author(s):

Abdelkader AMEUR AMEUR ◽

Onur YILMAZ ◽

Nezih ATA ◽

Ibrahim CEMAL ◽

Semir Bechir Suheil GAOUAR

Keyword(s):

Genetic Diversity ◽

Production Systems ◽

Productivity Loss ◽

Genetic Management ◽

Breeding Programs ◽

Sheep Breeds ◽

Genetic Clusters ◽

Native Sheep ◽

Sheep Production ◽

High Level

In Algeria and Turkey, the sheep production systems are based on the under extensive rural conditions and their genetic management has led to increased homozygosity and hence productivity loss. The identification of inter-breed and intra-breed genetic diversity plays a key role in the shaping of conservation and breeding programs. The present study was conducted to investigate the genetic diversity of native sheep breeds reared in Turkey and Algeria. A total of 240 animals from four Algerian (Hamra, Ouled Djellal, Sidaou, and Tazegzawt) and four Turkish (White Karaman, South Karaman, Karacabey Merino, and Kıvırcık) native sheep breeds were genotyped with fourteen microsatellite markers recommended by FAO. A total of 340 alleles were detected from fourteen markers studied. All the eight breeds exhibited moderate to high levels of genetic diversity, with a slight superiority of the Algerian sheep breeds. Overall FIS value was low, but highly significant (p < 0.001). It may have been due to the high inbreeding within the population. The mean global coefficient of gene differentiation (GST) showed that approximately 94.0 % of the genetic variation was within-population. The highest number of private alleles with a frequency above 5 % was observed in Ouled Djellal sheep. Structure analysis of populations studied revealed the most appropriate K with four genetic clusters. As the result, the dendrogram showed that the Algerian sheep breeds were completely separated from the Turkish sheep breeds furthermore the Bayesian clustering revealed a high level of admixture, especially in Algerian sheep populations.

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Molecular evidence for multiple origins of hybridogenetic fish clones (Poeciliidae:Poeciliopsis).

Genetics ◽

10.1093/genetics/127.2.391 ◽

1991 ◽

Vol 127 (2) ◽

pp. 391-398

Author(s):

J M Quattro ◽

J C Avise ◽

R C Vrijenhoek

Keyword(s):

Genetic Diversity ◽

Mitochondrial Dna ◽

Restriction Site ◽

Molecular Evidence ◽

Feedback Process ◽

Multiple Origins ◽

Northwestern Mexico ◽

Mtdna Diversity ◽

High Level ◽

Mtdna Variability

Abstract Hybrid matings between the sexual species Poeciliopsis monacha and Poeciliopsis lucida produced a series of diploid all-female lineages of P. monacha-lucida that inhabit the Río Fuerte of northwestern Mexico. Restriction site analyses of mitochondrial DNA (mtDNA) clearly revealed that P. monacha was the maternal ancestor of these hybrids. The high level of mtDNA diversity in P. monacha was mirrored by similarly high levels in P. monacha-lucida; thus hybridizations giving rise to unisexual lineages have occurred many times. However, mtDNA variability among P. monacha-lucida lineages revealed a geographical component. Apparently the opportunity for the establishment of unisexual lineages varies among tributaries of the Río Fuerte. We hypothesize that a dynamic complex of sexual and clonal fishes appear to participate in a feedback process that maintains genetic diversity in both the sexual and asexual components.

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SNP-Based Genotyping Provides Insight Into the West Asian Origin of Russian Local Goats

Frontiers in Genetics ◽

10.3389/fgene.2021.708740 ◽

2021 ◽

Vol 12 ◽

Author(s):

Tatiana E. Deniskova ◽

Arsen V. Dotsev ◽

Marina I. Selionova ◽

Henry Reyer ◽

Johann Sölkner ◽

...

Keyword(s):

Genetic Diversity ◽

Genetic Relationships ◽

Principal Component ◽

Production Traits ◽

Effective Population ◽

Altai Mountain ◽

Asian Origin ◽

Breeding Programs ◽

Population Sizes ◽

High Level

Specific local environmental and sociocultural conditions have led to the creation of various goat populations in Russia. National goat diversity includes breeds that have been selected for down and mohair production traits as well as versatile local breeds for which pastoralism is the main management system. Effective preservation and breeding programs for local goat breeds are missing due to the lack of DNA-based data. In this work, we analyzed the genetic diversity and population structure of Russian local goats, including Altai Mountain, Altai White Downy, Dagestan Downy, Dagestan Local, Karachaev, Orenburg, and Soviet Mohair goats, which were genotyped with the Illumina Goat SNP50 BeadChip. In addition, we addressed genetic relationships between local and global goat populations obtained from the AdaptMap project. Russian goats showed a high level of genetic diversity. Although a decrease in historical effective population sizes was revealed, the recent effective population sizes estimated for three generations ago were larger than 100 in all studied populations. The mean runs of homozygosity (ROH) lengths ranged from 79.42 to 183.94 Mb, and the average ROH number varied from 18 to 41. Short ROH segments (<2 Mb) were predominant in all breeds, while the longest ROH class (>16 Mb) was the least frequent. Principal component analysis, Neighbor-Net graph, and Admixture clustering revealed several patterns in Russian local goats. First, a separation of the Karachaev breed from other populations was observed. Moreover, genetic connections between the Orenburg and Altai Mountain breeds were suggested and the Dagestan breeds were found to be admixed with the Soviet Mohair breed. Neighbor-Net analysis and clustering of local and global breeds demonstrated the close genetic relations between Russian local and Turkish breeds that probably resulted from past admixture events through postdomestication routes. Our findings contribute to the understanding of the genetic relationships of goats originating in West Asia and Eurasia and may be used to design breeding programs for local goats to ensure their effective conservation and proper management.

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