A unique mutation in a MYB gene cosegregates with the nectarine phenotype in peach

PLoS One. 2014 Mar 3;9(3):e90574. doi: 10.1371/journal.pone.0090574. eCollection 2014.

Abstract

Nectarines play a key role in peach industry; the fuzzless skin has implications for consumer acceptance. The peach/nectarine (G/g) trait was described as monogenic and previously mapped on chromosome 5. Here, the position of the G locus was delimited within a 1.1 cM interval (635 kb) based on linkage analysis of an F2 progeny from the cross 'Contender' (C, peach) x 'Ambra' (A, nectarine). Careful inspection of the genes annotated in the corresponding genomic sequence (Peach v1.0), coupled with variant discovery, led to the identification of MYB gene PpeMYB25 as a candidate for trichome formation on fruit skin. Analysis of genomic re-sequencing data from five peach/nectarine accessions pointed to the insertion of a LTR retroelement in exon 3 of the PpeMYB25 gene as the cause of the recessive glabrous phenotype. A functional marker (indelG) developed on the LTR insertion cosegregated with the trait in the CxA F2 progeny and was validated on a broad panel of genotypes, including all known putative donors of the nectarine trait. This marker was shown to efficiently discriminate between peach and nectarine plants, indicating that a unique mutational event gave rise to the nectarine trait and providing a useful diagnostic tool for early seedling selection in peach breeding programs.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Breeding / methods*
  • Chromosome Mapping
  • Chromosomes, Plant / genetics*
  • Crosses, Genetic
  • DNA Primers / genetics
  • Genes, Plant / genetics*
  • Genetic Markers / genetics
  • Phenotype*
  • Polymerase Chain Reaction
  • Prunus / genetics*
  • Retroelements / genetics
  • Trichomes / genetics*

Substances

  • DNA Primers
  • Genetic Markers
  • Retroelements

Grants and funding

This work was supported by the Ministero delle Politiche Agricole Alimentari e Forestali–Italy (MiPAAF www.politicheagricole.it) through the project ‘DRUPOMICS’ (grant DM14999/7303/08) and by an Italian grant to DB funded by private and public agencies “MAS.PES: apricot and peach breeding by molecular-assisted selection”. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.