Recurrent genome recovery in backcross breeding programs of Passiflora edulis Sims based on SNP DArTseq sequencing

Abstract

The backcross method in Passiflora edulis Sims is used for genetic improvement with the aim of transferring disease-resistance from wild to commercial species. Recurrent genome recovery and the characterization of hybrids and potential parents with desirable traits are essential for the design of intra and interspecific crosses. In the present study, recurrent genome recovery and genetic variability of three genealogies comprising hybrids and wild species of Passiflora were evaluated. Eighty-four genotypes were evaluated using 3.717 biallelic codominant SNP markers generated through DArTseq (NGS) sequencing. To characterize the structure of the genotype panel, the three genealogies were independently analyzed by calculating the genetic distance and by hierarchical clustering analysis (UPGMA) principal coordinate analysis (PCoA), and intersection analysis (UpSetR). The genetic availability of SNPs was evaluated using Polymorphism Information Content (PIC), one ratio proportion, Minor Allele Frequency (MAF), and reproducibility with the adegenet package (R software). The results identified well-defined similarity groups between hybrids and parents, with a clear trend of clustering of accessions of the same species and of backcrossed genotypes closer to the recurrent parent. The present study emphasizes the efficiency of backcrossing to recover recurrent genome and the preservation of genetic variability to improve the sour passion fruit.