Genetic Diversity of Accessions and First Generation Progeny of the Mangaba Genebank

Abstract

Mangaba (Hancornia speciosa Gomes-Apocynaceae) is an important fruit tree in Brazil and has an unexplored stock germplasm collection. Commercial varieties are unavailable and little is known about its potential as a source of genetic diversity for molecular breeding programs. Progeny tests may improve studies on commercial variability and facilitate genetic improvement of the species. Our aim was to evaluate the genetic diversity and structure of accessions and progeny from the Mangaba Genebank of Embrapa Coastal Tablelands. We estimated the genetic diversity of 96 individuals using 4 SSR markers. The mean observed heterozygosity was lower than expected, showing an excess of homozygotes, corroborated by the positive coefficient of endogamy. The genetic diversity indexes (F st ) and Nei's unbiased genetic identity (GI) revealed, in general, moderate genetic diversity between accessions. The relationship between matrices and progenies showed that there may be a greater degree of genetic information sharing between the ABP1 and ABP2 accessions. The Bayesian analysis suggested the presence of two distinct groups of genotypes (K = 2). These results will assist future breeding programs and facilitate the conservation of mangaba.

Clonal Fidelity and Genetic Diversity of Micropropagated Hancornia speciosa Gomes (Apocynaceae) as Evaluated by Molecular Markers

“…Since H. speciosa shows a cross pollination and self-incompatible reproductive biology, we should expect a high genetic divergency among individuals. However, our analysis using ISSR and SSR markers revealed a low polymorphism between individuals, similar results in H. speciosa with SRR were observed by Bogea et al [75] and Soares et al [76] and with ISSR by Costa et al [46], Luz et al [18] and Santos et al [77]. These results can be explained by the fact that samples are taken from forest fragments close to farms (great anthropic activity), which can lead to a small number of specimens of the species in these places and to the successive crossing between related plants, leading to a decrease in genetic diversity within the region's population and can cause depression through inbreeding.…”

Research Article Genetic diversity of the mangaba GeneBank using microsatellites

“…There are nine mangaba germplasm banks distributed among Brazilian Agricultural Research Corporations -Embrapa (4); State Agricultural Research Corporation of Paraíba -Emepa (1); Federal University of Lavras -UFAL (1); Federal University of Goiás -UFG (1), and State University of Goiás -UEG (1). The Mangaba GeneBank (BGMangaba) belongs to Embrapa Coastal Tablelands; it is accredited by the Ministry of the Environment, and it is a reliable custodian of this specie's genetic patrimony (Soares et al, 2018). Knowledge of the genetic diversity preserved in this germplasm assists in conservation strategies and provides key information for breeding programs.…”

Identification and preliminary characterization of early fruiting mangabeira (Hancornia speciosa – Apocynaceae)

“…Genetic and morphological analysis of collections in germplasm banks is one of the first steps in the identification of duplicates and gene lines, which will then allow hybrids with greater commercial potential to be developed (Freitas et al, 2012). In addition, this provides a way of combining biodiversity conservation work with sustainable development (SOARES et al, 2018).…”

“…A caracterização de coleções de bancos de germoplasma consiste em um dos primeiros passos para a identificação de duplicatas e genitores, o que consequentemente possibilitará a obtenção de híbridos com maior potencial comercial (FREITAS et al, 2012). Além disso, é uma maneira de conciliar os trabalhos de conservação da biodiversidade com o desenvolvimento sustentável (SOARES et al, 2018).…”