Résumé
It remains a major challenge to identify the genes and mutations that lead to plant sexual differentiation. Here, we study the structure and evolution of the sex-determining region (SDR) in
Vitis
species. We report an improved, chromosome-scale Cabernet Sauvignon genome sequence and the phased assembly of nine wild and cultivated grape genomes. By resolving twenty
Vitis
SDR haplotypes, we compare male, female, and hermaphrodite haplotype structures and identify sex-linked regions. Coupled with gene expression data, we identify a candidate male-sterility mutation in the
VviINP1
gene and potential female-sterility function associated with the transcription factor
VviYABBY3
. Our data suggest that dioecy has been lost during domestication through a rare recombination event between male and female haplotypes. This work significantly advances the understanding of the genetic basis of sex determination in
Vitis
and provides the information necessary to rapidly identify sex types in grape breeding programs.
Grapevine is one of a few ancestrally dioecious crops that are reverted to hermaphroditism during domestication. Here, the authors identify candidate genes related to male- and female-sterility in grapes and describe the genetic process that led to hermaphroditism during domestication.