scholarly journals Genetic diversity and relationship between wild and cultivated cowpea [Vigna unguiculata (L.) Walp.] as assessed by allozyme markers

2021 ◽  
Vol 54 (1) ◽  
pp. 201-208
Author(s):  
Eric Bertrand Kouam ◽  
Geoffrey Mwanza Muluvi ◽  
Rémy Stéphane Pasquet
Keyword(s):  
Genetic Diversity ◽  
Genetic Variation ◽  
Genetic Bottleneck ◽  
Wild Plant ◽  
Cultivated Plants ◽  
Upgma Dendrogram ◽  
Traditional Agroecosystems ◽  
Isozyme Loci ◽  
The Mean ◽  
The Relationship

Abstract In Cameroon, cowpea plays an important role in traditional agroecosystems. Genetic variation in wild and cultivated cowpea in Cameroon has not yet been documented. Allozyme markers because of their codominance and polymorphism are useful tools for studying genetic variation and disparity in plant species. The present study was undertaken to elucidate the relationship between wild and cultivated cowpea from Cameroon. Ten enzyme systems encoding nineteen isozyme loci were used on 62 cowpea germplasm (45 wild and 17 cultivated). A total of thirty-two alleles were found. One allele was only found in cultivated samples (Enp98 ). Eight alleles were specific only to wild plant (Amp2 98 , Amp3a 103 , Amp4 96 , Fdh104 , Idh2 95 , Pgi3 92 , Pgm2 95 and Sdh95 ). Twenty-three alleles were common to both wild and cultivated accessions. Amp2 10 2 (z = −4.633, p < 0.001) and Fle3 96 (z = −2.858, p < 0.010) were significantly more represented in cultivated compared to wild cowpea forms. The mean number of alleles per locus in wild (1.632 alleles/locus) cowpea were significantly higher (t = 2.805, p < 0.010) compared to cultivated (1.263 alleles/locus) cowpea. Also, the proportion of polymorphic loci (P = 52.63%) and average Nei’s genetic diversity (He = 0.126) were important in wild, compared to the cultivated plants: P = 26.31% and He = 0.063, respectively. The low level of diversity found in domesticated accessions compared to wild can be attributed to a major genetic bottleneck that probably happened during the domestication process. Cluster analysis revealed by UPGMA dendrogram separated the 62 accessions into three clusters. Although an admixture of both wild and cultivated accessions within the same cluster were found, the dendogram, however, highlighted a visible separation between wild and cultivated cowpea. Wild cowpea with many more private alleles indicates an untouched resource available for future breeding.

scholarly journals Trunk perimeter correlates with genetic bottleneck intensity and the level of genetic diversity in populations of Taxus baccata L

2021 ◽  
Vol 78 (3) ◽  
Author(s):  
Sara Stefanowska ◽  
Katarzyna Meyza ◽  
Grzegorz Iszkuło ◽  
Igor J. Chybicki
Keyword(s):  
Genetic Diversity ◽  
Genetic Variation ◽  
Demographic History ◽  
Genetic Bottleneck ◽  
Tree Age ◽  
Taxus Baccata ◽  
Census Size ◽  
Germplasm Collections ◽  
History Of ◽  
The Mean

Abstract Key message Taxus baccata remnants established recently tend to contribute less to the species’ overall genetic variation than historical populations because they are subjected to a greater impact of the founder effect and genetic isolation. As tree trunk perimeter is a rough indicator of genetic variation in a population, this measure should be considered in conservation programs. Context Genetic variation within Taxus baccata (L.) populations is not associated with the current census size but correlates well with the effective size, suggesting that genetic drift intensity reflects variation in demographic histories. Aims We hypothesize that recently established populations are subjected to greater bottleneck than old remnants. Using the mean trunk perimeter as a surrogate of tree age, we test whether the demographic history and genetic variation are associated with the mean tree age. Methods Using 18 microsatellite markers, we analyze the genetic diversity and demographic history of 11 yew populations in Poland to assess the relationship between the mean trunk perimeter and the inferred genetic parameters. Results Populations reveal significant differences in levels of genetic variation and in the intensity and time of genetic bottleneck. After excluding an apparent outlier, the genetic variation is significantly greater while the bottleneck intensity lower in populations with a greater perimeter. Conclusion Due to continuous species decline and increasing fragmentation, the non-uniform contribution of yew remnants to the overall genetic variation tends to decrease together with the mean tree age. Germplasm collections for the species should take into account tree perimeter as a rough indicator of the genetic variation of a population.

Genetic Analysis of Chinese Cucumber Collections in the U.S. National Germplasm Collection

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 534e-534 ◽  
Author(s):  
J. Staub ◽  
Felix Sequen ◽  
Tom Horejsi ◽  
Jin Feng Chen
Keyword(s):  
Genetic Diversity ◽  
Principal Component Analysis ◽  
Genetic Variation ◽  
Genetic Analysis ◽  
Allelic Variation ◽  
Germplasm Collection ◽  
Principal Component ◽  
Isozyme Loci ◽  
National Plant Germplasm System ◽  
The U.S

Genetic variation in cucumber accessions from China was assessed by examining variation at 21 polymorphic isozyme loci. Principal component analysis of allelic variation allowed for the depiction of two distinct groupings of Chinese accessions collected in 1994 and 1996 (67 accessions). Six isozyme loci (Gpi, Gr, Mdh-2, Mpi-2, Pep-gl, and Pep-la) were important in elucidating these major groups. These groupings were different from a single grouping of Chinese 146 accessions acquired before 1994. Allelic variation in Chinese accessions allowed for comparisons with other accessions in the U.S. National Plant Germplasm System (U.S. NPGS) collection grouped by continent and sub-continent. When Chinese accessions taken collectively were compared with an array of 853 C. sativus U.S. NPGS accessions examined previously, relationships differed between accessions grouped by country or subcontinent. Data indicate that acquisition of additional Chinese and Indian cucumber accessions would be strategically important for increasing genetic diversity in the U.S. NPGS cucumber collection.

scholarly journals Genetic studies revealed differences between European and North American populations of Calypogeia azurea

2016 ◽  
Vol 42 (1) ◽  
pp. 19-26 ◽  
Author(s):  
Katarzyna Buczkowska ◽  
Alina Bączkiewicz ◽  
Patrycja Gonera
Keyword(s):  
Genetic Variation ◽  
North America ◽  
Genetic Distance ◽  
Gene Diversity ◽  
Oil Bodies ◽  
Genetic Studies ◽  
Isozyme Loci ◽  
The Mean ◽  
Different Parts ◽  
Nei's Genetic Distance

Abstract Calypogeia azurea, a widespread, subboreal-montane liverwort species, is one of a few representatives of the Calypogeia genus that are characterized by the occurrence of blue oil bodies. The aim of the study was to investigate the genetic variation and population structure of C. azurea originating from different parts of its distribution range (Europe and North America). Plants of C. azurea were compared with C. peruviana, another Calypogeia species with blue oil bodies. In general, 339 gametophytes from 15 populations of C. azurea were examined. Total gene diversity (HT) estimated on the basis of nine isozyme loci of C. azurea at the species level was 0.201. The mean Nei’s genetic distance between European populations was equal to 0.083, whereas the mean genetic distance between populations originating from Europe and North America was 0.413. The analysis of molecular variance (AMOVA) showed that 69% of C. azurea genetic variation was distributed among regions (Europe and North America), 15% - among populations within regions, and 16% - within populations. Our study revealed that C. azurea showed genetic diversity within its geographic distribution. All examined samples classified as C. azurea differed in respect of isozyme patterns from C. peruviana.

Life on the Edge: Geminiviruses at the Interface Between Crops and Wild Plant Hosts

2019 ◽  
Vol 6 (1) ◽  
pp. 411-433 ◽  
Author(s):  
Fernando García-Arenal ◽  
Francisco Murilo Zerbini
Keyword(s):  
Genetic Variation ◽  
Ecological Factors ◽  
Plant Viruses ◽  
Crop Plants ◽  
Wild Plants ◽  
Wild Plant ◽  
Cultivated Plants ◽  
Emerging Pathogens ◽  
Epidemiological Features ◽  
Virus Emergence

Viruses constitute the largest group of emerging pathogens, and geminiviruses (plant viruses with circular, single-stranded DNA genomes) are the major group of emerging plant viruses. With their high potential for genetic variation due to mutation and recombination, their efficient spread by vectors, and their wide host range as a group, including both wild and cultivated hosts, geminiviruses are attractive models for the study of the evolutionary and ecological factors driving virus emergence. Studies on the epidemiological features of geminivirus diseases have traditionally focused primarily on crop plants. Nevertheless, knowledge of geminivirus infection in wild plants, and especially at the interface between wild and cultivated plants, is necessary to provide a complete view of their ecology, evolution, and emergence. In this review, we address the most relevant aspects of geminivirus variability and evolution in wild and crop plants and geminiviruses’ potential to emerge in crops.

Genetic variation of rectal temperature in cows and its relationship to fertility

1982 ◽  
Vol 35 (3) ◽  
pp. 401-412 ◽  
Author(s):  
H. G. Turner
Keyword(s):  
Genetic Variation ◽  
Rectal Temperature ◽  
Bos Taurus ◽  
Cattle Breeding ◽  
Breeding Station ◽  
Parallel Effect ◽  
The Mean ◽  
Heat Tolerant ◽  
Calving Rate ◽  
The Relationship

ABSTRACTRectal temperatures of breeding cows at the National Cattle Breeding Station, ‘Belmont’, Rockhampton were recorded in each of 2 years. The data analysed represented two Bos taurus (Hereford × Shorthorn) and four B. indicus × B. taurus half-bred lines, and 800 to 900 cows in each year. Rectal temperatures averaged 39·8°C, and were 0·5°C higher in British breed than in zebu-cross cows and 0·3°C higher in lactating than in dry British cows (no effect in zebu cross).Fertility, measured as success or failure in producing a calf at term, was affected by rectal temperature (P<0·0001 in both years). The relationship was curvilinear, the reduction in calving rate due to 01°C increment in temperature being 0009 at 39°C, 002 at 40°C and 0035 at 41°C. Response of fertility to a given change in rectal temperature was the same in different breeds. The average depression of fertility due to heat susceptibility was 015 to 0·25 in British-breed and approximately 010 in zebu-cross herds.Even in relatively heat-tolerant zebu crossbreds and in a relatively mild environment on the Tropic, both the mean rectal temperature and its genetic variability within a herd had quite large effects on reproduction. The heritability of rectal temperature was 0·25 (s.e. 012) and its genetic correlation with fertility was −0·76 (s.e. 0·35). There was a parallel effect of rectal temperatures of cows on the birth weights of their calves.

Conservation genetics and ecology of the endangered rainforest shrub, Triunia robusta, from the Sunshine Coast, Australia

2002 ◽  
Vol 50 (1) ◽  
pp. 93 ◽  
Author(s):  
Alison Shapcott
Keyword(s):  
Genetic Diversity ◽  
Genetic Variation ◽  
Gene Flow ◽  
Conservation Genetics ◽  
Population Size ◽  
Genetic Similarity ◽  
Small Region ◽  
Geographic Proximity ◽  
Close Proximity ◽  
The Mean

Triunia robusta, which until recently was thought to be extinct, is now classified nationally as endangered. It is an understorey species restricted to the subcoastal rainforests in a small region of the Sunshine Coast, Queensland. The project involved sampling the genetic variation and measuring the population size and size distribution of T. robusta and its geographically closest congener T. youngiana, which occurs further south and has a wider geographic distribution. A total of 877 T. robusta plants were recorded across the 11 populations, approximately half (56.8&percnt;) of these were juveniles less than 1 m tall, whereas in T. youngiana only about 36.4&percnt; of a population was composed of juveniles. Genetic diversity was similar but significantly higher for T. robusta than T. youngiana if the very small T. robusta populations (2 or 3 plants) were excluded from analysis (P &lt; 0.05). The mean percentage of polymorphic loci among populations was high for both species. Triunia robusta is not, on average, more inbred than the more common T. youngiana. There was more differentiation between the T. robusta populations, which were in close proximity, than between the more geographically separated T. youngiana populations. Thus, there is evidence of more gene flow between populations of T. youngiana than between those of T. robusta. However, there was no geographic relationship between genetic similarity and geographic proximity in T. robusta

scholarly journals Regional Polymorphism Assessment of Myanmar ‘Sein Ta Lone’ Mango (Mangifera indica Linn) from Sintgaing Township Based on Microsatellite Markers

1970 ◽  
pp. 17-22
Author(s):  
May Sandar Kyaing ◽  
Sein Sandar May Phyo
Keyword(s):  
Genetic Diversity ◽  
Cluster Analysis ◽  
Genetic Variation ◽  
Microsatellite Markers ◽  
Mangifera Indica ◽  
Germplasm Management ◽  
Upgma Dendrogram ◽  
Expected Heterozygosity ◽  
Upgma Cluster Analysis ◽  
Relationship Of

This study was conducted to explore the genetic diversity and relationship of Sein Ta Lone mango cultivars among 20 commercial orchards in Sintgaing Township, Mandalay region. Nine microsatellite (SSR) markers were used to detect genetic polymorphism in a range from (3 to 6) alleles with (4.33) alleles per marker in average. Six out of nine microsatellite markers gave the PIC values of greater than (0.5). Among them, SSR36 held the highest PIC values of (0.691) while MiSHRS39 and MN85 possessed the least PIC values of (0.368) and (0.387) respectively. The genetic diversity was expressed as unbiased expected heterozygosity (UHe) value with an average of (0.561). The genetic relationship was revealed by (UPGMA) dendrogram in a range of (0.69 to 1.00). Based on UPGMA cluster analysis, three main clusters were classified among three different locations. This study was intended to help cultivar characterization and conservation for proper germplasm management with the estimation of genetic variation and relationship in the existing population of Sein Ta Lone mangoes in Sintgaing Township by microsatellite markers.  

Genetic Diversity and Population Genetic Structure in the Rare Chittering Grass Wattle, Acacia anomala Court

1988 ◽  
Vol 36 (3) ◽  
pp. 273 ◽  
Author(s):  
DJ Coates
Keyword(s):  
Genetic Diversity ◽  
Genetic Variation ◽  
Genetic Structure ◽  
Population Genetic Structure ◽  
Population Genetic ◽  
Genetic System ◽  
Small Population ◽  
Vegetative Multiplication ◽  
The Mean ◽  
Allozyme Loci

There are 10 known populations of Acacia anomala occurring in two small disjunct groups some 30 km apart. The Chittering populations reproduce sexually whereas the Kalamunda populations appear to reproduce almost exclusively by vegetative multiplication. The level and distribution of genetic variation were studied at 15 allozyme loci. Two loci were monomorphic in all populations. In the Chittering populations the mean number of alleles per locus was 2.0 and the expected panmictic heterozygosity (genetic diversity) 0.209. In the Kalamunda populations the mean number of alleles per locus was 1.15 and the expected panmictic heterozygosity 0.079, although the observed heterozygosity of 0.150 was only marginally less than the Chittering populations (0.177). These data support the contention that the Chittering populations are primarily outcrossing whereas the Kalamunda populations are clonal, with each population consisting of individuals with identical and, in three of the four populations, heterozygous, multilocus genotypes. The level of genetic diversity within the Chittering populations is high for plants in general even though most populations are relatively smsll and isolated. It is proposed that either the length of time these populations have been reduced in size and isolated is insufficient for genetic diversity to be reduced or the genetic system of this species is adapted to small population conditions. Strategies for the adequate conservation of the genetic resources of Acacia anomala are discussed.

Genetic variation within and among populations of Camelliajaponica (Theaceae) in Korea

1996 ◽  
Vol 26 (4) ◽  
pp. 537-542 ◽  
Author(s):  
Myong Gi Chung ◽  
Soon Suk Kang
Keyword(s):  
Genetic Diversity ◽  
Genetic Variation ◽  
Pollen Dispersal ◽  
Island Populations ◽  
Generation Times ◽  
Genetic Diversity And Structure ◽  
Stump Sprouting ◽  
Ability To Regenerate ◽  
The Mean ◽  
High Level

The genetic diversity and structure of 17 Korean populations of Camelliajaponica L., a broad-leaved evergreen tree, was examined. Although most populations are restricted to several islands near the southern and southwestern coast of the Korean Peninsula, they maintain higher levels of genetic variation within populations than do long-lived, woody angiosperms. For example, 13 of 16 loci examined were polymorphic in at least one population, the mean number of alleles per locus was 2.63, and mean expected heterozygosity was 0.265. These values were comparable with those for continuously distributed, mainland populations of C. japonica in Japan. However, a considerably high level of heterozygote deficiency was observed in Korean populations of C. japonica (mean FIS = 0.202). About 13% of the total genetic variation was found among populations (GST = 0.129). Indirect estimates of the number of migrants per generation (1.69, calculated from FST; 2.14, calculated from the mean frequency of eight private alleles) indicate that gene flow among island populations is moderate. Factors contributing to the high levels of genetic diversity found in the entire species of C. japonica include long generation times, ability to regenerate by stump sprouting, predominant outcrossing induced by animal vectors, and occasional pollen dispersal by birds.

Allozyme variation and population structure of Carex humilis var. nana (Cyperaceae) in Korea

2001 ◽  
Vol 79 (4) ◽  
pp. 457-463 ◽  
Author(s):  
Man Kyu Huh
Keyword(s):  
Genetic Diversity ◽  
Population Structure ◽  
Genetic Variation ◽  
North American ◽  
Population Level ◽  
Allozyme Variation ◽  
Population Divergence ◽  
Geographic Ranges ◽  
The Mean ◽  
Allozyme Loci

Genetic diversity and population structure of 22 Carex humilis var. nana Ohwi (Cyperaceae) populations in Korea were determined using genetic variation at 23 allozyme loci. This is a long-lived herbaceous species with a widespread distribution in eastern Asia. The 12 enzymes revealed 23 putative loci, of which 11 were polymorphic (47.8%). Genetic diversity at the varietal level and at the population level was 0.131 and 0.118, respectively. Total genetic diversity (HT = 0.274) and within population genetic diversity (HS = 0.256) were high, whereas the extent of the population divergence was relatively low (GST = 0.068). An indirect estimate of the number of migrants per generation (Nm = 3.42) indicated that gene flow was high among Korean populations. Wide geographic ranges, perennial herbaceous nature, and the persistence of multiple generations are associated with the high level of genetic variation. A distinct difference between Asian and North American Carex is shown in the proportion of genetic variation (GST) (p < 0.001). The mean GST of Asian Carex was estimated as 0.056; thus, only 5.6% of genetic variability was distributed among populations, whereas the mean GST of North American Carex was estimated as 19.5% (3.5 times higher). It is probable that the geographical distance between population pairs and presence or absence of glacial history may play roles in the substantial difference between both groups.Key words: Carex humilis var. nana, genetic diversity, population structure.

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