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1.
Tsitol Genet ; 44(2): 29-37, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20480808

RESUMO

Four bred grapevine varieties released for commercial cultivation in Ukraine, namely 'Antey Magarachskii', 'Rubinovyi Magaracha', 'Granatovyi Magaracha' and 'Rubin Golodrigi', and their putative parental forms were genotyped using six microsatellite loci. Genotypes were compared with breeding records to verify genetic relationships among varieties. Results of the analysis confirmed four of six parent-offspring relationships. Results of the analysis allow to assume that genotype 'Seyve Villard 20347' is the direct parent of 'Antey Magarachskii' instead of its grandparent. The first-studied accession believed to be that of Granatovyi Magaracha was identified as impurity. In order to verify the parentage of Granatovyi Magaracha, rest accessions of that variety and its putative parent Antey Magarachskii were additionally genotyped at 13 nuclear loci and at three chloroplast loci. The parent-offspring relationship was confirmed, as all Granatovyi Magaracha accessions had a common allele with the parent variety Antey Magarachskii at each locus and the same chlorotype A. Different Granatovyi Magaracha accessions could have been obtained via vegetative propagation of two seedlings which arose from one crossing.


Assuntos
Variação Genética , Repetições de Microssatélites/genética , Vitis/classificação , Vitis/genética , Vinho/classificação , Alelos , Núcleo Celular/genética , Cloroplastos/genética , DNA de Plantas/genética , Marcadores Genéticos/genética , Heterozigoto , Especificidade da Espécie , Ucrânia , Vitis/crescimento & desenvolvimento
2.
Animal ; 2(1): 160-6, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22444975

RESUMO

Milk production data from Holstein × Zebu cows in small farms (2.4 cows per farm on average) in Maharashtra, India, followed by Bharatiya Agro Industries Foundation (BAIF), an Indian non-governmental organisation, were analysed to evaluate the impact of simplified milk-recording systems. The aim was to investigate, in developing tropical areas, less-costly protocols compared with the one currently implemented at BAIF, used as a reference. The latter can be considered an 'AT2' protocol with the recording made by specialised technicians at 2-week intervals. The simplified protocols were simulated from an initial data file by sampling test days according to each protocol. Bias and accuracy on the 305-day cow milk production and on the resulting reliability of the estimated breeding value of bulls were the criteria used in the comparison with the reference protocol. One type of simplified protocol considered an increase in the interval between two tests to at least 4 and up to 8 weeks. Another alternative studied corresponded to the situation where milk yield information measured by the farmer is collected by the artificial insemination technicians themselves when visiting a farm. This could be an option in the case of very small herd sizes (two or three cows). The results suggest that simplifying the current milk-recording protocol leads to a clear decrease in accuracy of estimating 305-day cow production but it has a limited effect on the reliability of bull proofs. No economic comparison was carried out, but the results strongly suggest that properly managed simplified milk-recording schemes could permit a substantial decrease of costs of milk recording per cow without damaging the efficiency of progeny testing in tropical areas with small herd size. Moreover, with the proposed simplified milk-recording protocols, up to three to four times more bulls could be tested with the same number of records.

3.
Proc Natl Acad Sci U S A ; 94(18): 9996-10001, 1997 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-11038572

RESUMO

Recolonization of Europe by forest tree species after the last glaciation is well documented in the fossil pollen record. This spread may have been achieved at low densities by rare events of long-distance dispersal, rather than by a compact wave of advance, generating a patchy genetic structure through founder effects. In long-lived oak species, this structure could still be discernible by using maternally transmitted genetic markers. To test this hypothesis, a fine-scale study of chloroplast DNA (cpDNA) variability of two sympatric oak species was carried out in western France. The distributions of six cpDNA length variants were analyzed at 188 localities over a 200 x 300 km area. A cpDNA map was obtained by applying geostatistics methods to the complete data set. Patches of several hundred square kilometers exist which are virtually fixed for a single haplotype for both oak species. This local systematic interspecific sharing of the maternal genome strongly suggests that long-distance seed dispersal events followed by interspecific exchanges were involved at the time of colonization, about 10,000 years ago.

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