Avocado Genomics
Domestication history and heterodichogamy in avocado
Status: Published in G3: Genes, Genomes, Genetics (2023) Collaborators: Abraham Morales-Cruz, Rosa Figueroa Balderas, Eric Focht, Vanessa E.T.M. Ashworth, Skylar Wyant, Andrea Minio, Dario Cantu, Mary Lu Arpaia, Brandon S. Gaut
Overview
We created the first comprehensive reference genome for the Gwen avocado cultivar and used comparative genomics to uncover the domestication history of avocado (Persea americana). Our analysis revealed three independent domestication events and identified genomic regions contributing to heterodichogamy.
Genome Assembly
- Long-read sequencing (PacBio) to create high-quality reference genome
- Assembled 49,450 genes across 12 pseudo-chromosomes
- N50 of 3.37 megabases
- BUSCO score of 91%
Key Findings
Domestication History
- Identified 3 independent domestication events from wild populations
- The commercially dominant Hass avocado variety originated from Guatemalan ancestry
- Evidence for domestication events occurring over 1 million years ago
Heterodichogamy Genetics
- Discovered genomic regions associated with A-type vs B-type flowering
- Identified candidate genes for flowering time control
Impact
Scientific: First reference-quality genome for avocado enabling future genetic studies
Agricultural: Informs breeding programs for improved cultivars and provides molecular markers for heterodichogamy selection
Conservation: Reveals genetic diversity patterns important for germplasm preservation
Media Coverage
- SDSC News: “Avocado Genome is at the Center of New Study”
- UC San Diego Today: University-wide feature
- HPCwire: “SDSC Supports Breakthrough Study”
Publication
Solares, E.A., Morales-Cruz, A., et al. (2023). “Insights into the domestication of avocado and potential genetic contributors to heterodichogamy.” G3: Genes, Genomes, Genetics, 13(2).