Gene discovery could shave years off avocado breeding

Researchers at UC Riverside and UC Davis have solved a century-old mystery in agriculture. By identifying a specific gene that controls avocado flowering patterns, the team has created a way to skip years of waiting in the breeding process.

Avocado trees are categorized as A-type or B-type based on when their flowers open and close. Growers currently plant a mix of both types to ensure cross-pollination. Until now, breeders had to wait up to 10 years for a tree to mature and flower before they could identify its type. This process wasted time and valuable orchard space on seedlings that did not meet specific production requirements.

Through genetic analysis of over 500 individual trees, the research team identified the SDMYB gene. This genetic marker allows scientists to test seedlings immediately after germination. If a seedling carries the correct DNA, it can be kept for breeding or orchard development. If not, it can be discarded long before it takes up physical space.

The findings, published in the Proceedings of the National Academy of Sciences, track this flowering trait back 42 million years across 26 different species. While the discovery does not involve gene editing, it serves as a powerful diagnostic tool for modern agriculture. Breeders can now move toward developing high-quality B-type trees that provide pollination benefits while also producing commercially valuable fruit.

This development is a win for the California avocado industry, where growers have historically relied on less desirable varieties just to handle pollination duties. With this new marker, the goal is to produce orchards filled entirely with high-quality, high-yield trees. The team plans to incorporate this screening into their current breeding programs immediately.