Genetic diversity in red clover (Trifolium pratense L.) revealed by morphological and microsatellite (SSR) markers

Autor: Paula Menna Barreto Dias, Jean-Paul Sampoux, Miguel Dall'Agnol, Philippe Barre, Bernadette Julier
Přispěvatelé: Universidade Federal do Rio Grande do Sul (UFRGS), Unité de recherche Génétique et Amélioration des Plantes Fourragères (UGAPF), Institut National de la Recherche Agronomique (INRA)
Rok vydání: 2007
Předmět:
Zdroj: Euphytica
Euphytica, 2008, 160 (2), pp.189-205. ⟨10.1007/s10681-007-9534-z⟩
ISSN: 1573-5060
0014-2336
Popis: The NPGS-USDA core collection with 85 accessions of red clover, an important forage species, is little described. The goal of the present study was to evaluate the diversity of a set of accessions from the core collection at the morphological and molecular level in order to extract some valuable accessions for Brazilian red clover breeding programs. Twenty-one morphological traits, collected in field and greenhouse in South Brazil, and seven SSR markers were used to describe 57 accessions from the U.S. core collection and one population cultivated in Southern Brazil. Variation between accessions was large for most of the 21 morphological traits. A cluster analysis based on the morphological traits revealed five distinct clusters that separated the populations according to flowering earliness, as already described, but also according to persistency, growth habit and dry matter productivity. Over seven SSR loci, the number of alleles averaged 11.1 alleles per locus. Genetic diversity measured with SSR markers was high, with a mean expected heterozygosity of 0.86. An analysis of molecular variance revealed that the largest proportion of variation (83.6%) resided at the within population level. Although the molecular markers also separated accessions into five clusters, there was no coincidence between the composition of groups found with morphological and molecular data. Use of genetic diversity in breeding programs requires to use the most promising populations, to combine positive traits such as persistency and forage yield, and probably to use within population variation to detect valuable genotypes that could be used as parents of synthetic varieties.
Databáze: OpenAIRE
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