Molecular polymorphism and linkage analysis in sweet passion fruit, an outcrossing species

Abstract

One of the current challenges of tropical fruit crop improvement is to incorporate molecular marker-based approaches into conventional breeding programmes. This study was designed to build an integrated genetic map of the sweet passion fruit (Passiflora alata), a diploid (2n = 18) outcrossing species which is greatly appreciated for in natura consumption, and reported to inspire cosmetic and pharmaceutical companies to create plant-derived compounds. With this in mind, a full-sib family of 180 individuals was genotyped using different molecular marker types, such as amplified fragment length polymorphisms (AFLP), microsatellite-AFLP (M-AFLP), simple sequence repeats (SSR), resistance gene analogues (RGA) and target region amplification polymorphism (TRAP). On average, the rate of polymorphism between the parental genotypes was 20.3%. We also searched for single nucleotide polymorphisms (SNPs) in some AFLP bands and in seven gene fragments, and found one SNP every 87 bp. All SNPs were biallelic and occurred most frequently in putative gene fragments (81.5%) rather than in AFLP bands (60.0%) analyzed. Excellent gel profiles were obtained allowing the recognition of all types of segregation expected for a progeny of an outcrossing species. Multipoint linkage analysis was performed using OneMap software, with logarithm of the odds (LOD) score ≥ 5.6 and recombination fraction <0.5. The resulting integrated map consists of 549 markers, 2.0% of which fit a segregation ratio of 1:1:1:1, 1.3% a ratio of 1:2:1, 27.3% a ratio of 3:1 and 69.4% a ratio of 1:1. The map spanned a total of 2073.0 cM, with an average distance between adjacent markers of 3.8 cM. This is the first linkage study on sweet passion fruit and should prove useful for quantitative trait loci mapping.

Genetic Breeding and Diversity of the Genus Passiflora: Progress and Perspectives in Molecular and Genetic Studies

“…RGA markers have also contributed to linkage analysis and the construction of a recent genetic map for P. alata [84]. …”

“…of ArticleReferencesIsoenzymeEstimation of diversity (germplasm)3[118,119,120]RFLPEstimation of diversity (germplasm)1[121]RAPDEstimation of diversity (germplasm)15[7,8,58,62,63,80,81,122,123,124,125,126,127,128,129]Characterization and confirmation of hybrids3[47,72,113]Genetic mapping1[115]Others2[114,130]AFLPEstimation of diversity (germplasm)3[79,95,131]Genetic mapping2[84,86]SSREstimation of diversity (germplasm)4…”

Molecular Genetic Variability of Commercial and Wild Accessions of Passion Fruit (Passiflora spp.) Targeting ex Situ Conservation and Breeding

“…In addition to this low diversity, the percentage of polymorphic SSR loci observed in studies aimed at developing and characterizing SSR markers for passion fruit did not exceed 35% [40,41,54,58,60,61], with an average of less than 22% polymorphic loci. For example, Ortiz et al [62] did not observe polymorphism when evaluating the germplasm of wild and commercial passion fruit distributed throughout the Colombian territory using 17 SSR primers previously characterized by Oliveira et al [57] and Pádua et al [56].…”

Estudos genéticos em uma população segregante de maracujá-doce selecionada para qualidade de frutos

“…A população F1, constituída por 180 indivíduos, irmãos-germanos, foi usada para a construção do primeiro mapa genético da espécie (Pereira et al 2013); paralelamente, 100 indivíduos desta população foram analisados quanto à produção e qualidade de frutos, em plantios realizados em dois locais do Estado de São Paulo e durante dois anos consecutivos (Nunes 2010;Laperuta 2011). Em ambos os experimentos, foi adotado o delineamento em látice quadrado 10 x 10 com duas repetições por local.…”