Polymorphism of hordein-coding loci in cultivated barley (Hordeum vulgare L.) in Afghanistan

Polymorphism of hordeins encoded by the HrdA, Hrd B, and Hrd Floci was analyzed in 84 accessions of local barley (Hordeum vulgare L.) varieties from major agricultural regions of Afghanistan using starch gel electrophoresis. Forty alleles of the Hrd A locus with the frequencies from 0.12 to 32.73%, 62 alleles of the Hrd B locus with the frequencies from 0.12 to 14.29%, and five alleles of the Hrd Flocus with the frequencies from 0.59 to 32.15% have been identified. The conclusion about genetic similarity of barley populations from different regions of Afghanistan is made on the basis of cluster analysis of the matrix of allele frequencies in barley populations from 31 localities. The local barley populations form four unequal clusters. The largest cluster I includes populations from 14 localities of Afghanistan. The second largest cluster IV consists of populations from ten localities, and clusters II and III comprise populations from four and three localities, respectively. Each of the four clusters includes populations from different regions of northern and southern Afghanistan. Based on our results, we conclude that the diversity of hordein-coding loci and the distribution of their alleles among different regions of Afghanistan are the consequences of introduction of barley landraces and their distribution over trade routes.     

Polymorphism of hordein-coding loci in barley (<Emphasis Type="Italic">Hordeum vulgare</Emphasis> L.) populations of Iran and Central Asian countries

Starch gel electrophoresis was performed to study polymorphism of hordeins encoded by the Hrd A, Hrd B, and Hrd F loci in 366 local old barley accessions from Iran and Central Asian countries, including Turkmenistan, Uzbekistan, Tajikistan (Mountain Badahsan), and Kirgizia. In total, 60 alleles with frequencies of 0.0003–0.2818 were observed for the Hrd A locus, 106 alleles with frequencies of 0.0003–0.1603 were observed for the Hrd B locus, and five alleles with frequencies of 0.0164–0.4131 were observed for the Hrd F locus. The alleles and allele frequencies displayed irregular distributions in barley populations of the above countries. Cluster analysis of the matrix of allele frequencies in populations from known collection sites revealed a cluster structure of local barley populations within each country. Local populations formed five differently sized clusters in Iran, six in Turkmenistan, three in Uzbekistan, and three in Kirgizia. The variation and allele frequency distribution of the hordein-coding loci in Iran and Central Asian countries were assumed to result from the introduction and spreading of barley forms via migrations of husbandmen.     

Polymorphism of hordein-coding loci in barley (Hordeum vulgare L.) populations from the countries of Eastern Asia (China, Nepal, Pakistan, India)

In this study, starch gel electrophoresis was used to examine polymorphism of hordeins encoded by the Hrd A, Hrd B, and Hrd F loci in 201 accessions of barley landraces from China (including Tibet), Nepal, Pakistan, and India. Altogether, 50 alleles with the frequencies of 0.001?C0.2269 were determined for the Hrd A locus, 65 alleles with the frequencies of 0.001?C0.1612 were determined for the Hrd B locus, and five alleles with the frequencies of 0.001?C0.4537 were determined for the Hrd F locus. In barley populations from these countries, irregular distribution of alleles and allele frequencies was observed. Cluster analysis of the matrix of allele frequencies in populations from known sampling sites revealed cluster structure of local barley populations within each country. Local populations formed five differently sized clusters in Nepal, four such clusters in India, three clusters in China, and three clusters, in Pakistan. These results suggest that variation and allele frequency distribution of the hordein-coding loci in the countries of Eastern Asia resulted from the introduction and spreading of barley forms through the husbandmen migrations.     

Polymorphism of hordei-coding loci in Near Eastern local populations of cultivated barley (<Emphasis Type="Italic">Hordeum vulgare</Emphasis> L.)

Electrophoresis in starch gel has been used to study the polymorphism of hordeins encoded by loci Hrd A, Hrd B, and Hrd F in 140 local barley populations from the Near East, including 60, 34, 33, 8, and 5 populations from Syria, Jordan, Iraq, Palestine, and Israel, respectively. Fifty-seven Hrd A, 87 Hrd B, and 5 Hrd F alleles have been found. The alleles of these loci considerably differ in frequencies and distribution in populations from different Near Eastern countries. Cluster analysis of the matrix of the frequencies of alleles of hordei-coding locus alleles in barley populations from the Near East, North Africa, Ethiopia, and South Arabia has yielded two clusters. The first cluster includes barley populations from Israel, Palestine, Morocco, Tunisia, Algeria, and Egypt; the second cluster, populations from Iraq, Syria, Jordan, Yemen, and Ethiopia.     

Hordein locus polymorphism of cultivated barley (<Emphasis Type="Italic">Hordeum vulgare</Emphasis> L.) in Turkey

Starch gel electrophoresis has been used to study the polymorphism of hordeins encoded by the Hrd A, Hrd B, and Hrd F loci in 93 landrace specimens of barley assigned to 17 ancient provinces located in modern Turkey. Forty-five alleles of Hrd A with frequencies of 0.11–29.34%, 51 alleles of Hrd B with frequencies of 0.11–8.07%, and 5 alleles of Hrd F with frequencies of 0.75–41.29% have been detected. Cluster analysis of the matrix of allele frequencies has demonstrated that barley populations from different old provinces of Turkey are similar to one another. Cluster structure of local barley populations has been found, most populations (82%) falling into three clusters. The first cluster comprises barley populations from six provinces (Thracia, Bithynia, Pontus, Lydia, Cappadocia, and Armenia); the second cluster, populations from five provinces (Paphlagonia, Galatia, Lycaonia, Cilicia, and Mesopotamia); and the third one, populations from three provinces (Phrygia, Karia, and Lycia). Barley populations from Mysia, Pamphlya, and Syria do not fall in any cluster.     

Current state of the genetic polymorphism in spring barley (<Emphasis Type="Italic">Hordeum vulgare</Emphasis> L.) from Russia assessed by the alleles of hordein-coding loci

Starch gel electrophoresis was performed to study the polymorphism of hordeins encoded by the Hrd A, Hrd B, and Hrd F loci in 211 varieties of spring barley. For 41 of these varieties, the genetic formulas were established for the first time. In the two samples of varieties, the comparative analysis of allelic diversity and allele frequencies of hordein-coding loci was carried out. The first sample consisted of 101 spring barley varieties approved for the use on the territory of the Russian Federation in 1999, while the second sample included 160 spring barley varieties that were approved in 2014; 49 of these varieties were common for both samples. It is demonstrated that the current tendency to reduction of the proportion of heterogeneous spring barley varieties is mainly due to the introduction of foreign varieties homogeneous for the hordein-coding loci. At the same time, there is an increase in polymorphism of hordein-coding loci in modern spring barley varieties. The number of alleles for the Hrd A locus increased by five alleles, and for the Hrd B locus, by nine alleles. Along with the alleles recorded earlier in barley landrace populations and varieties bred in 20th century, three novel alleles of the Hrd A locus and four alleles of the Hrd B locus were identified. The number of alleles of the Hrd F locus remained unchanged (four), and the changes in their frequencies were small. At the same time, the changes in frequency observed for some alleles of the Hrd A and Hrd B loci were statistically significant. All newly identified alleles of hordein-coding loci were found with low frequencies (from 0.003 to 0.006), so despite the increased number of alleles, no statistically significant increase in genetic diversity in terms of μ and PIC indices was observed.     

Hordein Polymorphism in Barley Varieties from Northern Africa

Using starch gel electrophoresis, we examined polymorphism of hordein encoded by loci Hrd A, Hrd B, and Hrd F in 77 accessions of local barley varieties from Northern African countries (9 from Marocco, 22 from Algeria, 7 from Tunisia, and 39 from Egypt). For loci Hrd A, Hrd B, andHrd F, respectively 35, 43, and 5 alleles were found. The existence of families of blocks of hordein components encoded by Hrd A and Hrd Bwas demonstrated. The estimation of genetic distances and cluster analysis showed similarity of barley populations from different Northern African countries with regard to alleles of the hordein-coding loci. We suggest that polymorphism at the hordein-coding loci in the populations examined has been mainly formed beyond Northern Africa, where barley has been repeatedly introduced. Apparently, the examined populations from Ethiopia and Egypt are not directly associated.     

Hordein locus polymorphism in near eastern local populations of cultivated barley (Hordeum vulgare L.)

Electrophoresis in starch gel has been used to study the polymorphism of hordeins encoded by loci Hrd A, Hrd B, and Hrd F in 140 local barley populations from the Near East, including 60, 34, 33, 8, and 5 populations from Syria, Jordan, Iraq, Palestine, and Israel, respectively. Fifty-seven Hrd A, 87 Hrd B, and 5 Hrd F alleles have been found. The alleles of these loci considerably differ in frequencies and distribution in populations from different Near Eastern countries. Cluster analysis of the matrix of the frequencies of hordein locus alleles in barley populations from the Near East, North Africa, Ethiopia, and South Arabia has yielded two clusters. The first cluster includes barley populations from Israel, Palestine, Morocco, Tunisia, Algeria, and Egypt; the second cluster, populations from Iraq, Syria, Jordan, Yemen, and Ethiopia.     

Polymorphism of the cultivated barley (<Emphasis Type="Italic">Hordeum vulgare</Emphasis> L.) of South Arabia at hordein-coding loci

Electrophoresis in starch gel was used to study the polymorphism of hordeins controlled by loci Hrd A, Hrd B, and Hrd F in 89 accessions of the local barleys from South Arabia (Yemen). Overall, 36 alleles were detected for locus Hrd A; 48 alleles, for Hrd B; and 5 alleles, for Hrd F. The existence of the blocks of hordein components controlled by loci Hrd A and Hrd B was demonstrated. Calculation of genetic distances allows us to conclude that the barley populations from Yemen and Ethiopia are more similar compared with the populations from Egypt. This confirms the hypothesis of Bakhteev on the origin of Ethiopian barleys.     

Polymorphism of hordein-coding loci in barley (Hordeum vulgare L.) populations of Iran and Central Asian countries

Starch gel electrophoresis was performed to study polymorphism of hordeins encoded by the Hrd A, Hrd B, and Hrd Floci in 366 local old barley accessions from Iran and Central Asian countries, including Turkmenistan, Uzbekistan, Tajikistan (Mountain Badahsan), and Kirgizia. In total, 60 alleles with frequencies of 0.0003-0.2818 were observed for the Hrd A locus, 106 alleles with frequencies of 0.0003-0.1603 were observed for the Hrd B locus, and five alleles with frequencies of 0.0164-0.4131 were observed for the Hrd Flocus. The alleles and allele frequencies displayed irregular distributions in barley populations of the above countries. Cluster analysis of the matrix of allele frequencies in populations from known collection sites revealed a cluster structure of local barley populations within each country. Local populations formed five differently sized clusters in Iran, six in Turkmenistan, three in Uzbekistan, and three in Kirgizia. The variation and allele frequency distribution of the hordein-coding loci in Iran and Central Asian countries were assumed to result from the introduction and spreading of barley forms via migrations of husbandmen.     

Hordein Polymorphism in Ethiopian Barley

Using starch gel electrophoresis, polymorphism of hordein-encoding loci Hrd A, Hrd B, and Hrd Fwas studied in 147 accessions of local Ethiopian barley cultivars. Loci Hrd A, Hrd B, and Hrd Fwere shown to have 26, 36, and 4 alleles, respectively. The allele frequencies in the collection examined varied from 0.17 to 45.72%. For loci Hrd Aand Hrd B, families of blocks of hordein components were found. Based on the allele frequencies and their combinations at loci Hrd Aand Hrd Bas well as the numbers of families of component blocks of hordeins A and B, we identified genotypes that could be considered as the most ancient in Ethiopia. A catalog of hordein variant encoded by these loci was created. The list of hordein genetic formulas for the studied accessions is presented.     

Distribution of the Allelic Variants of Three Hordein-Coding Loci of Spring Barley in Russia

The distribution of alleles of the hordein-coding loci Hrd A, Hrd B, and Hrd Fwas investigated in 101 spring barley cultivars grown in 12 regions of Russia in 1999. It was demonstrated that the genetic structure of populations of these cultivars in the regions studied was affected by climatic factors, such as the average June temperature and average annual rainfall. The distribution patterns of the Hrdalleles in 25 agricultural provinces of the former Soviet Union and 12 regions of Russia were compared. The factor structure of genetic variability in the regions of barley cultivation in the former Soviet Union was found to differ from that in Russia. The change of the factor structure is likely to be related to diminishing the barley-production area under study and to the new administrative subdivision.     

Hordein locus polymorphism of cultivated barley (Hordeum vulgare L.) in Turkey

Starch gel electrophoresis has been used to study the polymorphism of hordeins encoded by the Hrd A, Hrd B, and Hrd F loci in 93 landrace specimens of barley assigned to 17 ancient provinces located in modem Turkey. Forty-five alleles of Hrd A with frequencies of 0.11-29.34%, 51 alleles of Hrd B with frequencies of 0.11-8.07%, and 5 alleles of Hrd F with frequencies of 0.75-41.29% have been detected. Cluster analysis of the matrix of allele frequencies has demonstrated that barley populations from different old provinces of Turkey are similar to one another. Cluster structure of local barley populations has been found, most populations (82%) falling into three clusters. The first cluster comprises barley populations from six provinces (Thracia, Bithynia, Pontus, Lydia, Cappadocia, and Armenia); the second cluster, populations from five provinces (Paphlagonia, Galatia, Lycaonia, Cilicia, and Mesopotamia); and the third one, populations from three provinces (Phrygia, Karia, and Lycia). Barley populations from Mysia, Pamphlya, and Syria do not fall in any cluster.     

Hordein polymorphism in barley varieties fom North Africa

Using starch gel electrophoresis, we examined polymorphism of hordein encoded by loci Hrd A, Hrd B, and Hrd F in 77 accessions of local barley varieties from North African countries (9 from Marocco, 22 from Algeria, 7 from Tunisia, and 39 from Egypt). For loci Hrd A, Hrd B, and Hrd F, respectively 35, 43, and 5 alleles were found. The existence of families of blocks of hordein components encoded by Hrd A and Hrd B was demonstrated. The estimation of genetic distances and cluster analysis showed similarity of barley populations from different North African countries with regard to alleles of the hordein-coding loci. We suggest that polymorphism at the hordein-coding loci in the populations examined has been mainly formed beyond North Africa, where barley has been repeatedly introduced. Apparently, the examined populations from Ethiopia and Egypt are not directly associated.     

Polymorphism of the cultivated barley (Hordeum vulgare L.) of South Arabia at hordein-coding loci

Electrophoresis in starch gel was used to study the polymorphism of hordeins controlled by loci Hrd A, Hrd B, and Hrd F in 89 samples of the local barleys from South Arabia (Yemen). Overall, 36 alleles were detected for locus Hrd A; 48 alleles, for Hrd B; and 5 alleles, for Hrd F. The existence of the blocks of hordein components controlled by loci Hrd A and Hrd B was demonstrated. Calculation of genetic distances allows us to conclude that the barley populations from Yemen and Ethiopia are more similar compared with the populations from Egypt. This confirms the hypothesis of Bakhteev on the origin of Ethiopian barleys.     

Population structure of rice (Oryza sativa) landraces from high altitude area of Indian Himalayas

This study examined the genetic diversity in 20 rice landrace populations from parts of traditional farming areas of the Indian Himalayas using 11 mapped simple sequence repeats (SSR) loci. Twenty‐four individuals sampled from each of the 20 landraces (480 individuals), which were collected from farmers from Northwest to Northeast Himalaya, showed that all landraces showed within population variation and none were homogeneous. The number of polymorphic loci in a landrace population ranged from 5 to 11. A total of 71 alleles were recorded of which 58 were common and 13 were rare. Of the 71 alleles, 46 were common to both Northwest and Northeast regions, whereas 9 were unique to the former and 16 were unique to the latter. The mean number of alleles per locus was 6.45 and for landrace populations from Northwest and Northeast regions were 5.0 and 5.64, respectively. Population differentiation, as shown by a high F_ST value (0.61), was greater for Northeast populations. The unweighted pair group method with arithmetic mean (UPGMA) dendrogram classified the populations into three major clusters: cluster I comprised seven populations from the Northwest region, cluster II comprised seven populations from the Northeast region and cluster III comprised populations from both regions. Investigating the population genetic structure can help monitor change in diversity over time and space, and also help devise a rational plan for management of crop landraces on‐farm under farmer management.     

Population Genetic Structure of Pacific White Shrimp (<Emphasis Type="Italic">Litopenaeus vannamei</Emphasis>) from Mexico to Panama: Microsatellite DNA Variation

Genetic variation and population structure of wild white shrimp (Litopenaeus vannamei) from 4 geographic locations from Mexico to Panama were investigated using 5 microsatellite DNA loci. The genetic diversity between populations was indicated by the mean number of alleles per locus and mean observed heterozygosity, which ranged from 7.4 to 8.6 and from 0.241 to 0.388, respectively. Significant departures from Hardy-Weinberg equilibrium were found at most locations at each locus, with the exception Guatemala at Pvan0013, and were caused by high heterozygote deficiencies. Genetic differences between localities were detected by pairwise comparison based on allelic and genotypic frequencies, with the exception of locus Pvan1003. Significant pairwise F _ST values between locations and total F _ST showed that the white shrimp population is structured into subpopulations. However, population differentiation does not follow an isolation-by-distance model. Knowledge of the genetic diversity and structure of L.vannamei populations will be of interest for aquaculture and fisheries management to utilize and preserve aquatic biodiversity.     

Geographic distribution of alleles at the Ga2 locus for segregation distortion in barley

Summary A distorted segregation of esterase alleles at the complex loci, Est1, Est2 and Est4, was found in an F₂ population. This distortion is typical for cross combinations between the Ga2Ga2 and ga2ga2 genotypes responsible for segregation distortion, since the Ga2 locus is linked with the complex loci encoding the esterase isozymes. The segregation of esterase isozyme patterns in F₂ populations between 473 varieties of barley and a tester of ga2ga2 genotype was examined, and the genotypes inducing segregation distortion were detected. Varieties with a ga2ga2 genotype are widely distributed throughout the world, whereas Ga2Ga2 varieties are found only in eastern and southern regions of Asia, from Japan to North India, with a low frequency. In varieties collected from these regions, some associations were detected between alleles at the Ga2 locus and esterase isozyme patterns. Additionally, most of the Ga2 barley varieties are naked and possess a BtBtbt2bt2 genotype for a non-brittle rachis.     

Uniformity of distributing alleleic variants of three hordein-coding loci of spring barley in the Russian Federation]

The distribution of alleles of the hordein-coding loci Hrd A, Hrd B, and Hrd F was investigated in 101 spring barley cutivars grown in 12 regions of Russia in 1999. It was demonstrated that the genetic structure of populations of these cutivars in the regions studied was affected by climatic factors, such as the average June temperature and average annual precipitation. The distribution patterns of the Hrd alleles in 25 agricultural provinces of the former Soviet Union and 12 regions of Russia were compared. The factor structure of genetic variability in the regions of barley cultivation in the former Soviet Union was found to differ from that in Russia. The change of the factor structure is likely to be related to diminishing the barley-production area under study and to the new administrative subdivision.     

Association of genetic polymorphisms with fertilization in the chicken

Summary Associations between fertilization rate and genotypes at four polymorphic loci were studied in three relatively non-inbred populations of Light Sussex chickens. In sires the genotypes tested were at theB blood-group locus only; in dams, at theB locus and three egg-white loci. Data were available for purebred matings of related substrains 6D and 6F and the ancestor strain 6 from which they were derived and for crossbred matings of 6D and 6F by two related Rhode Island Red/New Hampshire strains.In analyses of variance by dam genotypes within sires, no locus or combination of loci had a significant effect on fertilization rate. In analyses by sire and damB blood-group genotypes, no significant effects were found in 6F. SireB genotypes showed a very significant effect (P<0.001) on fertilization rate in 6D, and in 6. The latter effect was not fully acceptable since there was a significant (P<0.02) sirex damB genotypes interaction effect in 6. This interaction took the form of a lowered fertility in matings where sire and dam had the sameB genotype. The significant main effect in 6D was due to significant differences between the fertilization rates of the three most frequent sire genotypes. The same differences were not found in the other two strains. Similarly, significant sireB genotype differences in the Rhode Island Red/New Hampshire mates of 6F were not repeated in those of 6D.Combination of this result with those from our previous work with embryonic mortality in these strains is still insufficient fully to explain the continued segregation of four alleles at theB blood group locus.