<b>Genetic diversity between native and improved <i>Cattleya walkeriana</i> Gardner famous clones

Abstract

ABSTRACT. The aim of this study was to evaluate the genetic diversity among native plants and some individuals obtained from crosses with unknown genealogy of C. walkeriana as well as C. loddigesii and C. nobilior and to advance towards solving the question of the genetic purity of the "Orchidglade" clone. Eight microsatellite loci were used to evaluate the genetic diversity between individuals of C. walkeriana. Microsatellites were not efficient in determining the genetic diversity between C. walkeriana groups (native and improved). The difficulty in determining the genetic distance between the different genotypes can be attributed to the complex mating system of the species and to a weak genetic barrier that facilitates the development of hybrids. Our analysis revealed smaller genetic distances between the "Orchidglade", "Equilab", "Kenny" and "Pedentive" clones and the species C. loddigesii and C. nobilior. Native C. walkeriana plants were genetically more distant from the C. loddigesii and C. nobilior species.Keywords: orchid improvement, genetic variation, genetic differentiation, Cattleya loddigesii, Cattleya nobilior.Diversidade genética entre clones famosos nativos e melhorados de Cattleya walkeriana Gardner RESUMO. O objetivo desta pesquisa foi o de avaliar a diversidade genética entre plantas nativas e indivíduos de genealogia desconhecida de C. walkeriana, bem como C. loddigesii e C. nobilior, e também avançar na solução do dilema da origem do clone "Orchidglade" de C. walkeriana. Oito locos microssatélites foram utilizados para avaliar a diversidade genética entre indivíduos de C. walkeriana. Os marcadores microssatélites não foram eficientes na determinação da diversidade genética entre os grupos C. walkeriana (nativas e melhoradas). A dificuldade em determinar a distância genética entre os genótipos diferentes pode ser devida a um sistema complexo de reprodução das espécies e devido a uma fraca barreira reprodutiva facilitando o desenvolvimento de híbridos. Nossa análise revelou menores distâncias genéticas entre os clones Orchidglade, "Equilab", "Kenny" e "Pedentive" e as espécies C. loddigesii e C. nobilior. As C. walkeriana nativas se mostraram geneticamente mais distantes das espécies de C. loddigesii e C. nobilior. Palavras-chave: melhoramento de orquídeas, variação genética, diferenciação genética, Cattleya loddigesii, Cattleya nobilior.

Genetic Variability Analysis of Phaius spp Orchid based on RAPD Markers

“…The closer to 1, the more similar the species, while the closer to 0 the more genetically diverse species (Fig 2). The small genetic distance between cluster 1 and cluster 2 reflects the low genetic barrier within the species [23]. The further distance of species in a dendrogram cluster will increase genetic diversity.…”

A new set of microsatellite loci for Cattleya walkeriana Gardner, an endangered tropical orchid species and its transferability to Cattleya loddigesii Lindl. and Cattleya nobilior Reichenbach

“…The characterization of germplasm and analyses of population and conservation genetics based on molecular markers have gained importance due to the speed and quality of the generated data (de Vicente et al ., 2005; Govindaraj et al ., 2015). Microsatellites (SSRs) are highly informative molecular markers (Oliveira et al ., 2006; Vieira et al ., 2016) that have been developed for many plant species and are currently used in molecular breeding, germplasm evaluation, genetic diversity, genome mapping, hybridization and evolutionary studies (Gupta and Varshney, 2000; Govindaraj et al ., 2015; Tambarussi et al ., 2017).…”