Genetic Switch Discovery Could Shave Years Off Avocado Breeding

Scientists at University of California (UC) Davis and UC Riverside have discovered the gene responsible for controlling avocado flowering patterns, solving a century-old agricultural mystery. The discovery, published in the Proceedings of the National Academy of Sciences, identifies a floral transcription factor gene named SDMYB that dictates whether an avocado tree develops an A-type or B-type flowering rhythm.

The timing of avocado blooms is critical for commercial orchards. All avocado flowers open first as female and later reopen as male, but A- and B-type varieties operate on staggered schedules so neighboring trees can cross-pollinate. Until now, breeders had to wait five to 10 years for seedlings to mature and bloom just to determine their flower type. Because of this long wait, growers frequently dedicated up to 10% of their land to B-type pollinizer trees that produced fruit with little commercial value.

The newly discovered genetic marker allows researchers to test seedling DNA and identify flower types almost immediately. By removing years of trial-and-error, breeders can quickly select and cultivate high-quality B-type varieties similar to UCR's popular Luna avocado that maximize pollination while producing premium fruit for market.

For more details, read the article in UC Riverside News.