Genetic diversity of the species Cnesterodon hypselurus (Cyprinodontiformes: Poeciliidae) in Cinzas River basin: new record and headwater capture evidences

Cnesterodon hypselurus is a small fish that has a restricted distribution in southern Brazil, including headwaters of the Tibagi and Itararé river basins (Upper Paraná River). This study reported C. hypselurus in a headwater of Cinzas River basin, where there were no previous records of this species, and employed microsatellite loci and mitochondrial haplotypes in a population genetic analysis. A total of 57 specimens was analyzed, including 30 from Cinzas River basin, 25 from Itararé River basin and two from Tibagi River basin. Results indicated low genetic diversity levels (HE = 0.334 and h = 0.246) for the sample from Cinzas River, suggesting reflections of a founder effect after the species had dispersed from one watershed to another, possibly by headwater captures. Since different populations were detected between the Cinzas and Itararé rivers (DEST = 0.248, P-value < 0.05) and other occurrence sites are still unknown in the Cinzas River basin, the data herein have great relevance and should be taken into account in future management and conservation actions, as well as in evolutionary studies of C. hypselurus.(AU)

Cnesterodon hypselurus é um pequeno peixe que possui distribuição restrita no sul do Brasil, incluindo cabeceiras das bacias dos rios Tibagi e Itararé (alto rio Paraná). Este estudo reportou C. hypselurus na cabeceira da bacia do rio das Cinzas, onde não havia registros prévios desta espécie, e empregou locos microssatélites e haplótipos mitocondriais em uma análise genética de populações. Um total de 57 espécimes foi analisado, incluindo 30 do rio das Cinzas, 25 da bacia do rio Itararé e dois da bacia do rio Tibagi. Os resultados indicaram baixos níveis de diversidade genética (HE = 0,334 e h = 0,246) para a amostra do rio das Cinzas, sugerindo reflexos de um efeito fundador após a espécie ter dispersado de uma bacia para a outra, possivelmente a partir de captura de cabeceiras. Uma vez que diferentes populações foram detectadas entre os rios das Cinzas e Itararé (DEST = 0,248, valor de P < 0,05) e que outros pontos de ocorrência ainda são desconhecidos na bacia do rio das Cinzas, os dados do presente estudo mostram grande relevância e deveriam ser considerados em futuras ações de manejo e conservação, bem como em estudos evolutivos de C. hypselurus.(AU)

Diagnostic locus for identification of silverside hybrids (Odontesthes humensis and Odontesthes bonariensis) in a natural population / Locus diagnóstico para identificação de híbridos de peixe-rei (Odontesthes humensis and Odontesthes bonariensis) em população natural

Hybridization is a natural phenomenon that occurs more often in fish than in other vertebrates. The use of nuclear and mitochondrial molecular markers provides valuable results in the detection of these events. The aim of this study was to investigate the occurrence of interspecific hybrids in natural populations of silverside. The samples of Odontesthes humensis, Odontesthes bonariensis, and indivi-duals that were morphologically different from pure species were collected in the Mangueira lagoon, located in southern Brazil. Result: Six tetranucleotide microsatellite loci were synthesized and tested. The UFPEL_OH3 locus proved to be diagnostic for the detection of silverside hybrids, and it was possi-ble to distinguish between pure and hybrid species. The mitochondrial marker gene cytb synthesized from conserved Odontesthes sequences in the GenBank genetic database showed no differences in the genetic sequence of the samples, needing further studies to confirm the hypothesis.(AU)

A hibridação é um fenômeno natural que ocorre mais frequentemente em peixes do que em outros vertebrados. Para detectá-la, são utilizados marcadores moleculares nucleares e mitocondriais, os quais fornecem resultados valiosos. O objetivo deste estudo foi investigar a ocorrência de híbridos in-terespecíficos em populações naturais de peixe-rei. As amostras de Odontesthes humensis, Odontesthes bonariensis e de indivíduos morfologicamente diferentes das espécies puras foram coletadas na lagoa Mangueira, localizada no Sul do Brasil. Foram sintetizados e testados seis loci microssatélites tetranu-cleotídeos. O locus UFPEL_OH3 mostrou-se um diagnóstico para detectar híbridos de peixe-rei, pos-sibilitando a distinção de espécies puras de híbridas. O marcador mitocondrial gene cytb, sintetizado com base nas sequências conservadas de Odontesthes no banco de dados genéticos do GenBank, não apresentou diferenças na sequência genética das amostras, portanto, são necessários mais estudos para confirmar a hipótese de hibridação.(AU)

Outbreak of toxoplasmosis associated with muscular lesions in finishing pigs caused by an atypical Toxoplasma gondii genotype / Surto de toxoplasmose associado a lesões musculares em suínos de terminação causado por um genótipo atípico de T. gondii

Toxoplasma gondii infections are usually asymptomatic in pigs, and an acute clinical disease is rare in this host. This study aimed to determine the pathological and molecular aspects of an outbreak of fatal systemic toxoplasmosis in finishing pigs in Brazil. The outbreak occurred on a commercial finishing pig farm in the state of Santa Catarina in southern Brazil. The farm had 1500 pigs and 3.8% of mortality rate during the outbreak. The pigs had fever, anorexia, apathy, and locomotor deficits. Seven pigs were necropsied. Gross findings included multifocal to coalescent pale areas in skeletal muscles, lymphadenomegaly, hepatosplenomegaly, and non-colapsed lungs. The histological findings included granulomatous lymphadenitis, hepatitis and splenitis, necrotizing myositis, and lymphoplasmacytic interstitial pneumonia. Lung and liver lesions were occasionally accompanied by T. gondii parasitic structures. Positive immunolabeling for T. gondii tachyzoites and encysted bradyzoites was detected in all examined pigs. PCR-RFLP (11 markers) and microsatellite analysis (15 markers) identified the non-archetypal genotype #278 in pigs. This is the first report of systemic toxoplasmosis in pigs with muscle lesions and additionally shows the diversity of disease-causing T. gondii genotypes circulating in animals in Brazil.(AU)

As infecções por Toxoplasma gondii são geralmente assintomáticas em suínos, e uma doença clínica aguda é rara nessa espécie. Este estudo teve como objetivo determinar os aspectos patológicos e moleculares de um surto de toxoplasmose sistêmica fatal em suínos em terminação no Brasil. O surto ocorreu em uma granja comercial de suínos em terminação no estado de Santa Catarina, no sul do Brasil. A granja tinha 1500 suínos e a taxa de mortalidade durante o surto foi de 3,8%. Os suínos apresentaram febre, anorexia, apatia e déficits locomotores. Sete suínos foram necropsiados. Os achados macroscópicos incluíram áreas pálidas multifocais a coalescentes nos músculos esqueléticos, linfadenomegalia, hepatoesplenomegalia e pulmões não colapsados. Os achados histológicos incluíram linfadenite, hepatite, esplenite granulomatosa e miosite necrosante, assim como pneumonia intersticial linfoplasmocítica. Lesões pulmonares e hepáticas foram ocasionalmente acompanhadas por estruturas parasitárias de T. gondii. A imunomarcação positiva para taquizoítos e bradizoítos encistados de T. gondii foi observada em todos os suínos examinados. PCR-RFLP (11 marcadores) e análise de microssatélites (15 marcadores) identificaram o genótipo não arquetípico #278 em suínos. Este é o primeiro relato de toxoplasmose sistêmica em suínos com lesões musculares e, adicionalmente, demonstra a diversidade de genótipos de T. gondii causadores de doenças circulantes em animais no Brasil.(AU)

Microsatellite Polymorphism and Prokaryotic Expression of Mef2d in Xingyi Duck

Myocyte enhancer factor 2D (MEF2D) are members of the myocyte enhancer factor 2 (MEF2), a supergene family and are thought to be related to the development and regeneration of skeletal muscle. We selected a microsatellite locus located in the MEF2D gene to study the slaughter characteristics of Xingyi duck and discuss whether the locus could be used as a molecular genetic marker associated with the slaughter characteristics. To further study the function of this gene, we cloned the coding region of the MEF2D gene and expressed it in the prokaryotic expression system. We amplified exon 9 of MEF2D gene by PCR and analyzed after sequencing. The entire CDS region was amplified by RT-PCR. The prokaryotic expression vector was constructed by double enzyme digestion. Results showed that there was a significant correlation between the microsatellite polymorphism of exon 9 of the MEF2D gene and the eviscerated weight rate of Xingyi duck (p<0.05). The eviscerated weight rate of the aa (40/40) genotype was significantly higher than that of the ab (40/49) genotype. The CDS region of the MEF2D gene was cloned with a length of 1557 bp. The prokaryotic expression vector pET32a(+)-MEF2D was constructed. The results provide a foundation for future studies examining the function of the MEF2D.(AU)

Microsatellite Polymorphism and Prokaryotic Expression of Mef2d in Xingyi Duck

Myocyte enhancer factor 2D (MEF2D) are members of the myocyte enhancer factor 2 (MEF2), a supergene family and are thought to be related to the development and regeneration of skeletal muscle. We selected a microsatellite locus located in the MEF2D gene to study the slaughter characteristics of Xingyi duck and discuss whether the locus could be used as a molecular genetic marker associated with the slaughter characteristics. To further study the function of this gene, we cloned the coding region of the MEF2D gene and expressed it in the prokaryotic expression system. We amplified exon 9 of MEF2D gene by PCR and analyzed after sequencing. The entire CDS region was amplified by RT-PCR. The prokaryotic expression vector was constructed by double enzyme digestion. Results showed that there was a significant correlation between the microsatellite polymorphism of exon 9 of the MEF2D gene and the eviscerated weight rate of Xingyi duck (p<0.05). The eviscerated weight rate of the aa (40/40) genotype was significantly higher than that of the ab (40/49) genotype. The CDS region of the MEF2D gene was cloned with a length of 1557 bp. The prokaryotic expression vector pET32a(+)-MEF2D was constructed. The results provide a foundation for future studies examining the function of the MEF2D.

Genetic diversity assessment for the vulnerable migratory cownose ray Rhinoptera bonasus (Myliobatiformes: Rhinopteridae) from the southwestern Atlantic Ocean

ABSTRACT Rhinoptera bonasus is a bento-pelagic and highly migratory species occurring from southern United States to northern Argentina. Due to overfishing effects, R. bonasus is currently at risk, classified by the IUCN Red List as vulnerable. Considering the lack of molecular data available for R. bonasus, this study aimed to describe the genetic variability and population structure of specimens sampled from three Brazilian coast ecoregions (Amazon ecoregion, Pará; Northeastern ecoregion, Pernambuco and Southeastern ecoregion, Rio de Janeiro, São Paulo and Santa Catarina), through five polymorphic microsatellite markers. Here testing the panmixia hypothesis for Brazilian ecoregions and test natal philopathy. A total of 69 analyzed specimens revealed individual and significant genetic differentiation between the sampled locations. ST (0.12), PCA, DAPC and Bayesian analyses of the genetic population structure revealed at least two distinct genetic R. bonasus groupings. IBD tests were significant, indicating a correlation between genetic and geographical distance among populations, which can be explained by reproductive philopatric behavior. Philopatric behavior associated with R. bonasus mobility may influence the differentiation values observed for all loci in the investigated samples.

RESUMO Rhinoptera bonasus é uma espécie bento-pelágica e altamente migratória, que ocorre do sul dos Estados Unidos ao norte da Argentina. Devido aos efeitos da sobrepesca, R. bonasus está atualmente em risco, classificada pela Lista Vermelha da IUCN como vulnerável. Considerando a falta de dados moleculares disponíveis para R. bonasus, este estudo teve como objetivo descrever a variabilidade genética e estrutura populacional de espécimes amostrados em três ecorregiões do litoral brasileiro (Ecorregião Amazônica, Pará; Ecorregião Nordeste, Pernambuco e Ecorregião Sudeste, Rio de Janeiro, São Paulo e Santa Catarina), por meio de cinco marcadores microssatélites polimórficos. Assim, testaremos as hipóteses de panmixia e filopatria natal. Um total de 69 espécimes analisados revelou diferenciação genética individual e significativa entre os locais amostrados. As análises de ST (0,12), PCA, DAPC e Bayesiana revelaram pelo menos dois agrupamentos genéticos distintos de R. bonasus. Os testes de IBD foram significativos, indicando uma correlação entre a distância genética e geográfica entre as populações, o que pode ser explicado pelo comportamento filopátrico reprodutivo. O comportamento filopátrico associado à mobilidade de R. bonasus pode influenciar os valores de diferenciação observados para todos os loci nas amostras investigadas.

A lima bean core collection based on molecular markers

Some germplasm collections have a high number of accessions, which makes it difficult to explore the genetic variability present in the germplasm bank due to the redundancy and the difficulty of detailed analysis of all conserved accessions. Therefore, our study aimed to analyze the genetic diversity of 153 lima bean (Phaseolus lunatus) accessions for the purpose of constructing a core collection. Eleven SSRs were used for this purpose. The 153 lima bean accessions can be represented by low redundancy using a minimum of 34 accessions, thus representing 22 % of the size of the entire germplasm bank. The core collection had a higher Shannon diversity index and expected heterozygosity (1.906 and 0.811, respectively) than those presented by the entire germplasm bank (1.605 and 0.713, respectively), indicating a higher polymorphism of the representative cultivars in relation to the entire collection. The accessions selected for the core collection may be used in future studies of genome association as well as in genetic crosses in breeding programs aimed at developing improved cultivars with high genetic diversity which can meet current and future market needs.

Interactions Between Non-Allelic Loci and Their Effects on Categorized Meat Performance Traits in Ducks

Traits associated with meat performance are characterized by a complex inheritance model, including the effects of non-allelic interactions. The aim of this study was to estimate the significance of non-allelic interactions between pairs of loci in each of two alternative groups based on four important performance traits of ducks: body weight (BW), carcass yield calculated as the ratio of carcass weight to body weight (CY), breast and leg muscle yield as a fraction of carcass weight (BL-CW), and skin weight and abdominal fat, again as a fraction of carcass weight (SF-CW). The experimental material was based on an F2 cross between two parental lines: A-55 (Polish Peking) and GL-30 (French Peking). In total, 368 individuals were recorded. All of the birds (including parents and F1) were genotyped for 23 polymorphic microsatellite loci. Entropy was taken as a measure of interaction between pairs of loci, and the chi-square test was used to verify significance. In total, 253 pairs of loci were analyzed in both categories of each of the four traits. Statistically significant interactions were obtained for each trait. However, it was observed that some of the loci showed a greater tendency to have significant opposite interactions for alternative categories of the same trait. The results indicate the dependence of the recombination rate within pairs of loci on the level of each of the four traits.(AU)

A lima bean core collection based on molecular markers

Some germplasm collections have a high number of accessions, which makes it difficult to explore the genetic variability present in the germplasm bank due to the redundancy and the difficulty of detailed analysis of all conserved accessions. Therefore, our study aimed to analyze the genetic diversity of 153 lima bean (Phaseolus lunatus) accessions for the purpose of constructing a core collection. Eleven SSRs were used for this purpose. The 153 lima bean accessions can be represented by low redundancy using a minimum of 34 accessions, thus representing 22 % of the size of the entire germplasm bank. The core collection had a higher Shannon diversity index and expected heterozygosity (1.906 and 0.811, respectively) than those presented by the entire germplasm bank (1.605 and 0.713, respectively), indicating a higher polymorphism of the representative cultivars in relation to the entire collection. The accessions selected for the core collection may be used in future studies of genome association as well as in genetic crosses in breeding programs aimed at developing improved cultivars with high genetic diversity which can meet current and future market needs.(AU)

Interactions Between Non-Allelic Loci and Their Effects on Categorized Meat Performance Traits in Ducks

Traits associated with meat performance are characterized by a complex inheritance model, including the effects of non-allelic interactions. The aim of this study was to estimate the significance of non-allelic interactions between pairs of loci in each of two alternative groups based on four important performance traits of ducks: body weight (BW), carcass yield calculated as the ratio of carcass weight to body weight (CY), breast and leg muscle yield as a fraction of carcass weight (BL-CW), and skin weight and abdominal fat, again as a fraction of carcass weight (SF-CW). The experimental material was based on an F2 cross between two parental lines: A-55 (Polish Peking) and GL-30 (French Peking). In total, 368 individuals were recorded. All of the birds (including parents and F1) were genotyped for 23 polymorphic microsatellite loci. Entropy was taken as a measure of interaction between pairs of loci, and the chi-square test was used to verify significance. In total, 253 pairs of loci were analyzed in both categories of each of the four traits. Statistically significant interactions were obtained for each trait. However, it was observed that some of the loci showed a greater tendency to have significant opposite interactions for alternative categories of the same trait. The results indicate the dependence of the recombination rate within pairs of loci on the level of each of the four traits.

Genetic characterization of selected Nile tilapia in Santa Catarina / Caracterização genética de tilápia-do-nilo selecionadas em Santa Catarina

Different Nile tilapia stocks belonging to the fish breeding program of the Epagri (Empresa de Pesquisa Agropecuária e Extensão Rural de Santa Catarina) were characterized by microsatellite markers. A total of nine stocks (S1 to S9) were evaluated, and for each stock the caudal fin of 30 individuals were sampled. A total of 75 alleles were found at the 11 microsatellite loci used (UNH104, UNH108, UNH160, UNH208, UNH222, UNH848, UNH879, UNH898, UNH952, UNH998). Among the loci used, only UHN160 showed significance for null alleles in stocks S1, S2, S3 and S5. The average number of alleles per loci was 6.8, while the average number of alleles per tilapia stock was 4.4. Five unique alleles were identified between the stock S1 and S5. The observed heterozygosity values (Ho) exceeded the expected heterozygosity (He), resulting in a negative inbreeding coefficient (FIS = -0.092). FST for the total population was 0.109, demonstrating moderate genetic differentiation between the stocks. According to the Euclidean distance, three groups were formed as follows: I - S6, S7 and S9; II - S2, S3 and S4; and III - S1, S5 and S8. However, the existence of two groups can be observed from the PCoA representation: I - S6, S7, S8 and S9; and II - S1, S2, S3, S4 and S5. The formation of these two genetic groups is consistent with the genealogy of stocks. The formation of group III (S1, S5 and S8) in the dendrogram can be explained by the higher average observed heterozygosity values of these stocks. Bayesian analysis revealed the formation of 16 groups with an FST value of 0.2107. This result reinforces the existence of variability existing in the Epagri breeding program, from which it is possible to form heterotic groups to enable the direction of potential crosses to obtain genetic gain. The study enabled genotypic characterization of the tilapia brood stock used in the Epagri breeding program, determining the genetic distance between the stocks, which will enable more accurate selection of individuals for mating for the next generation. It was possible to verify that there is high heterozygosity within the stocks, and moderate genetic differentiation between the stocks. Furthermore, all evaluated markers were polymorphic for this brood stock and will be used to characterize the next generations.(AU)

Diferentes plantéis de tilápia-do-nilo pertencentes ao programa de melhoramento genético de peixes da Epagri (Empresa de Pesquisa Agropecuária e Extensão Rural de Santa Catarina) foram caracterizados por meio de marcadores microssatélites. Ao total foram avaliados nove plantéis (S1 a S9), e para cada foram amostrados nadadeira caudal de 30 indivíduos. O total de 75 alelos foram encontrados nos 11 loci microssatélites utilizados (UNH104, UNH108, UNH160, UNH208, UNH222, UNH848, UNH868, UNH879, UNH898, UNH952, UNH998). Entre os loci utilizados, apenas o UHN160 apresentou significância para alelos nulos nos estoques S1, S2, S3 e S5.A média do número de alelos por loci foi 6,8, enquanto a média do número de alelos por plantel de reprodutores foi 4,4. Foram encontrados cinco alelos exclusivos entre os plantéis S1 e S5. Os valores de heterozigosidade observada (Ho) foi maior do que a esperada (He), resultando em um coeficiente de endogamia (FIS) médio negativo (-0,092). O FST encontrado para a população total foi de 0,109, evidenciando moderada diferenciação genética entre os plantéis. De acordo com a distância euclidiana, três grupos foram formados da seguinte forma: I - S6, S7 e S9; II - S2, S3 e S4; e III - S1, S5 e S8. Porém, a partir da representação do PCoA, observa-se a existência de dois grupos: I - S6, S7, S8 e S9; e II - S1, S2, S3, S4 e S5. A formação desses dois grupos genéticos é consistente com a genealogia dos plantéis de reprodutores. A formação do grupo III (S1, S5 e S8) no dendrograma pode ser explicada pelos maiores valores médios de heterozigosidade observados desses plantéis. A análise bayesiana mostrou a formação de 16 grupos com um valor de Fst de 0,2107. Esse resultado reforça a existência de variabilidade existente no programa de melhoramento Epagri, a partir do qual é possível formar grupos heteróticos para permitir cruzamentos potenciais para obter ganho genético. O estudo permitiu a caracterização genotípica dos plantéis de reprodutores de tilápia utilizado no programa de melhoramento Epagri, determinando a distância genética entre eles, o que permitirá a seleção mais precisa dos indivíduos para os acasalamentos da próxima geração. Foi possível verificar que há alta heterozigosidade entre os plantéis de reprodutores e moderada diferenciação genética entre eles. Além disso, todos os marcadores avaliados foram polimórficos para este estoque de matrizes e serão utilizados para caracterizar as próximas gerações.(AU)

Characterization of hilly chickens in consideration of climate change factors: light and heat

Hilly chickens were characterized from January 2015 to September 2016 considering climate factors (light and heat). The experimental birds were divided into three groups (heat stress; light and control). The heat was generated in the chickens shelter by a black shaded light (Lantern) for two to three hours more after sunset. A lighting device (Lantern) was kept in the chickens shelter for the same period for increasing daylight duration. The individual chickens egg production, egg weight and mature live weight were studied from onset of egg production. It was observed that reddish brown hilly type chicken produced more (100.80 no/year/chicken) and larger sized (43.21g) eggs than spotted chicken (83.4 no/year/chicken and 40.46g). Among the three treatments, the lighting group produced 7.71 and 5.60 more eggs than the control and heat stress group, and one hour lighting lengths increased egg production 4 to 5.8%. Fifty-five blood samples were collected, and DNA was isolated from whole blood. For genetic characterization, 10 microsatellites markers from FAO recommendation list were used in this study. PCR amplification was performed in an MJ PTC-200 Peltier Thermal Cycler. The gene flow among breeds and genetic differentiation was assessed by computing between-breed genetic parameters: molecular co-ancestry (fij). It was found that genetic diversity of these two types of chickens was moderate. Results indicated that they were originated from the same ancestor. Therefore, priority should be given for implementation of appropriate breeding programme and strategies are necessary to avoid loss of genetic diversity.(AU)

Characterization of hilly chickens in consideration of climate change factors: light and heat

Hilly chickens were characterized from January 2015 to September 2016 considering climate factors (light and heat). The experimental birds were divided into three groups (heat stress; light and control). The heat was generated in the chickens shelter by a black shaded light (Lantern) for two to three hours more after sunset. A lighting device (Lantern) was kept in the chickens shelter for the same period for increasing daylight duration. The individual chickens egg production, egg weight and mature live weight were studied from onset of egg production. It was observed that reddish brown hilly type chicken produced more (100.80 no/year/chicken) and larger sized (43.21g) eggs than spotted chicken (83.4 no/year/chicken and 40.46g). Among the three treatments, the lighting group produced 7.71 and 5.60 more eggs than the control and heat stress group, and one hour lighting lengths increased egg production 4 to 5.8%. Fifty-five blood samples were collected, and DNA was isolated from whole blood. For genetic characterization, 10 microsatellites markers from FAO recommendation list were used in this study. PCR amplification was performed in an MJ PTC-200 Peltier Thermal Cycler. The gene flow among breeds and genetic differentiation was assessed by computing between-breed genetic parameters: molecular co-ancestry (fij). It was found that genetic diversity of these two types of chickens was moderate. Results indicated that they were originated from the same ancestor. Therefore, priority should be given for implementation of appropriate breeding programme and strategies are necessary to avoid loss of genetic diversity.

Phenotypic and molecular characterization of apple (Malus × domestica Borkh) genetic resources in Greece

ABSTRACT: The phenotypic and genetic analysis of apple (Malus × domestica Borkh) genotypes is essential for breeding species. Information on the morphology and genetic structure of apple offers significant help for germplasm maintenance and selection of suitable material to breed superior cultivars. This study shows the results of an investigation on the morphology and the genetic diversity for 19 apple cultivars, which are preserved in an ex situ collection in Naoussa, Central Macedonia, Greece. Information was recorded over a 5-year period for 47 traits describing plant morphology and phenotype, as well as leaf and fruit quality. Data were analyzed using the principal component analysis (PCA) method. The Euclidean distance metric and the Wards agglomeration method were used in an unsupervised hierarchical cluster analysis of all cultivars. The cultivars were grouped into four main clusters, suggesting that the characterized apple collection has a high potential for specific breeding goals. Furthermore, the cultivars were genotyped using seven microsatellite primers. Moderate levels of polymorphism were detected, and 38 distinctive alleles (5.4 alleles per primer pair) were identified. Both multivariate clustering approach (phenotypic data) and the genetic distance clustering approach (genetic data) grouped the apple cultivars according to their type. Hence, these data could be used for protection or patenting processes of existing or new apple cultivars carried out by the EU-Community Plant Variety Office.

Phenotypic and molecular characterization of apple (Malus × domestica Borkh) genetic resources in Greece

The phenotypic and genetic analysis of apple (Malus × domestica Borkh) genotypes is essential for breeding species. Information on the morphology and genetic structure of apple offers significant help for germplasm maintenance and selection of suitable material to breed superior cultivars. This study shows the results of an investigation on the morphology and the genetic diversity for 19 apple cultivars, which are preserved in an ex situ collection in Naoussa, Central Macedonia, Greece. Information was recorded over a 5-year period for 47 traits describing plant morphology and phenotype, as well as leaf and fruit quality. Data were analyzed using the principal component analysis (PCA) method. The Euclidean distance metric and the Wards agglomeration method were used in an unsupervised hierarchical cluster analysis of all cultivars. The cultivars were grouped into four main clusters, suggesting that the characterized apple collection has a high potential for specific breeding goals. Furthermore, the cultivars were genotyped using seven microsatellite primers. Moderate levels of polymorphism were detected, and 38 distinctive alleles (5.4 alleles per primer pair) were identified. Both multivariate clustering approach (phenotypic data) and the genetic distance clustering approach (genetic data) grouped the apple cultivars according to their type. Hence, these data could be used for protection or patenting processes of existing or new apple cultivars carried out by the EU-Community Plant Variety Office.(AU)

Phenotypic and molecular characterization of apple (Malus × domestica Borkh) genetic resources in Greece

ABSTRACT: The phenotypic and genetic analysis of apple (Malus × domestica Borkh) genotypes is essential for breeding species. Information on the morphology and genetic structure of apple offers significant help for germplasm maintenance and selection of suitable material to breed superior cultivars. This study shows the results of an investigation on the morphology and the genetic diversity for 19 apple cultivars, which are preserved in an ex situ collection in Naoussa, Central Macedonia, Greece. Information was recorded over a 5-year period for 47 traits describing plant morphology and phenotype, as well as leaf and fruit quality. Data were analyzed using the principal component analysis (PCA) method. The Euclidean distance metric and the Wards agglomeration method were used in an unsupervised hierarchical cluster analysis of all cultivars. The cultivars were grouped into four main clusters, suggesting that the characterized apple collection has a high potential for specific breeding goals. Furthermore, the cultivars were genotyped using seven microsatellite primers. Moderate levels of polymorphism were detected, and 38 distinctive alleles (5.4 alleles per primer pair) were identified. Both multivariate clustering approach (phenotypic data) and the genetic distance clustering approach (genetic data) grouped the apple cultivars according to their type. Hence, these data could be used for protection or patenting processes of existing or new apple cultivars carried out by the EU-Community Plant Variety Office.

Bioethanol strains of Saccharomyces cerevisiae characterised by microsatellite and stress resistance

Strains of Saccharomyces cerevisiae may display characteristics that are typical of rough-type colonies, made up of cells clustered in pseudohyphal structures and comprised of daughter buds that do not separate from the mother cell post-mitosis. These strains are known to occur frequently in fermentation tanks with significant lower ethanol yield when compared to fermentations carried out by smooth strains of S. cerevisiae that are composed of dispersed cells. In an attempt to delineate genetic and phenotypic differences underlying the two phenotypes, this study analysed 10 microsatellite loci of 22 S. cerevisiae strains as well as stress resistance towards high concentrations of ethanol and glucose, low pH and cell sedimentation rates. The results obtained from the phenotypic tests by Principal-Component Analysis revealed that unlike the smooth colonies, the rough colonies of S. cerevisiae exhibit an enhanced resistance to stressful conditions resulting from the presence of excessive glucose and ethanol and high sedimentation rate. The microsatellite analysis was not successful to distinguish between the colony phenotypes as phenotypic assays. The relevant industrial strain PE-2 was observed in close genetic proximity to rough-colony although it does not display this colony morphology. A unique genetic pattern specific to a particular phenotype remains elusive.(AU)

Successful Identification of Duck Genome Region Determining Desirable Uniformity of Meat Performance Traits

ABSTRACT The objective of this study was to identify genome regions determining duck meat performance traits with possible small variation. In total, 368 crossbred ducks of F2 generation obtained from two parental lines: Pekin-type ducks of Polish origin (A55) and Pekin-type ducks of French origin (GL-30) were recorded. The following seven traits were analyzed: body weight, breast muscle weight, leg muscle weight, water holding capacity in the breast and leg muscles, and color lightness L* of the breast and leg muscles. All birds (including parental and F1 generations) were genotyped (29 microsatellite markers). Means and coefficients of variation (CV) were calculated for 28 full-sibs (four sires by six dams and one sire by four dams). Number of progeny per full-sib group ranged from 7 to 17. The multivariate cluster analysis using grouping by k-means algorithm was used on transformed data. The multivariate cluster analysis gave two clusters: first group with 10 full-sibs and second one with 18 families. Differences among half-sibs in the CV of the recorded traits were determined. It should be noted that one out of five sire groups showed statistically significant differences from the other ones. Moreover, the CVs in this group were smaller. The analysis of microsatellite markers indicated three alleles from three loci were present only in the superior sire group. The obtained results indicate a promising opportunity of effective selection for improving carcass technological quality using molecular markers.(AU)

Successful Identification of Duck Genome Region Determining Desirable Uniformity of Meat Performance Traits

ABSTRACT The objective of this study was to identify genome regions determining duck meat performance traits with possible small variation. In total, 368 crossbred ducks of F2 generation obtained from two parental lines: Pekin-type ducks of Polish origin (A55) and Pekin-type ducks of French origin (GL-30) were recorded. The following seven traits were analyzed: body weight, breast muscle weight, leg muscle weight, water holding capacity in the breast and leg muscles, and color lightness L* of the breast and leg muscles. All birds (including parental and F1 generations) were genotyped (29 microsatellite markers). Means and coefficients of variation (CV) were calculated for 28 full-sibs (four sires by six dams and one sire by four dams). Number of progeny per full-sib group ranged from 7 to 17. The multivariate cluster analysis using grouping by k-means algorithm was used on transformed data. The multivariate cluster analysis gave two clusters: first group with 10 full-sibs and second one with 18 families. Differences among half-sibs in the CV of the recorded traits were determined. It should be noted that one out of five sire groups showed statistically significant differences from the other ones. Moreover, the CVs in this group were smaller. The analysis of microsatellite markers indicated three alleles from three loci were present only in the superior sire group. The obtained results indicate a promising opportunity of effective selection for improving carcass technological quality using molecular markers.

Genetic diversity of tambaqui broodstocks in stock enhancement programs / Diversidade genética de estoques de reprodutores de tambaqui utilizados em programas de repovoamento

Natural populations of tambaqui (Colossoma macropomum) have significantly decreased in recent decades especially due to human extraction activities. So that the environmental impact may be reduced, the restocking of fish and increase in fish production are enhanced. Genetic evaluations using molecular markers are essential for this purpose. Current study evaluates the genetic variability of two tambaqui broodstocks used in restocking programs. Sixty-five samples (33 samples from broodstock A and 32 samples from broodstock B) were collected. DNA was extracted from caudal fin samples, with the amplification of four microsatellite loci: Cm1A11 (EU685307) Cm1C8 (EU685308) Cm1F4 (EU685311) and Cm1H8 (EU685315). Fourteen alleles in the stock of broodstock A were produced, five alleles for Cm1A11 locus (230, 255, 260, 270 and 276 bp), three alleles Cm1C8 (239, 260, and 273 bp), two alleles Cm1F4 (211 and 245 bp), four alleles for Cm1H8 (275, 290, 320 and 331 bp) and two unique alleles were found for Cm1A11 loci (alleles 270 and 276 bp) and Cm1H8 (alleles 275 and 331 bp). In broodstock B, ten alleles were produced, the same alleles of the first stock except for alleles 270 and 276 bp in Cm1A11 locus and 275 and 331 bp in Cm1H8 locus. Broodstock A revealed low frequency alleles in Cm1A11 loci, Cm1C8, Cm1F4 and Cm1H8, whereas broodstock B had no locus with low allelic frequency. Loci Cm1A11, Cm1C8 and Cm1H8 exhibited significant deficit of heterozygotes in both broodstocks, revealing changes in Hardy-Weinberg equilibrium. Genetic diversity between stocks was 0.1120, whilst genetic similarity was 0.894, with FST rate = 0.05, and Nm = 3.93, indicating gene flow between the two broodstocks. Results show that broodstocks are genetically closely related, with no great genetic variability...(AU)

A população natural do tambaqui (Colossoma macropomum) está reduzindo significativamente nas últimas décadas devido às ações antrópicas, como o extrativismo. Para diminuir este impacto ambiental, o repovoamento de peixes e aumento da produção piscícola estão sendo realizados. Para tanto, avaliações genéticas por meio de marcadores moleculares são fundamentais. Desta forma, o objetivo deste trabalho foi avaliar a variabilidade genética de dois estoques de reprodutores de tambaqui utilizados em programas de repovoamento. Foram coletadas 65 amostras (33 amostras do estoque A e 32 amostras do estoque B). O DNA foi extraído de amostras da nadadeira caudal, com a amplificação de quatro loci microssatélite: Cm1A11 (EU685307), Cm1C8 (EU685308), Cm1F4 (EU685311) e Cm1H8 (EU685315). Foram produzidos 14 alelos no estoque de reprodutores A, cinco alelos para o locus Cm1A11 (230, 255, 260, 270 e 276 pb), três alelos para Cm1C8 (239, 260 e 273 pb), dois alelos para Cm1F4 (211 e 245 pb), quatro alelos para Cm1H8 (275, 290, 320 e 331 pb) e dois alelos exclusivos foram encontrados para os loci Cm1A11 (alelos 270 e 276 pb) e Cm1H8 (alelos 275 e 331 pb). Para o estoque de reprodutores B foram produzidos 10 alelos, os mesmos alelos do primeiro estoque, exceto para os alelos 270 e 276 pb no locus Cm1A11 e 275 e 331 pb no locus Cm1H8. No estoque de reprodutores A foi observado alelos de baixa frequência nos loci Cm1A11, Cm1C8, Cm1F4 e Cm1H8. Já o estoque de reprodutores B não apresentou locus com baixa frequência alélica. Os loci Cm1A11, Cm1C8 e Cm1H8 exibiram significativo défict de heterozigotos em ambos os estoques de reprodutores, indicando alteração no equilíbrio de Hardy-Weinberg. A divergência genética foi de 0,1120 entre os estoques, enquanto a similaridade genética foi de 0,894, com o valor de FST igual a 0,05, e o Nm igual a 3,93 indicando fluxo gênico entre os dois estoques de reprodutores...(AU)