Researchers identify gene linked to avocado flowering type

Researchers have identified a gene that determines whether avocado trees follow the Type A or Type B flowering pattern, according to a USDA Agricultural Research Service study published in Fruit Research.

The finding could make avocado breeding faster. Breeders currently have to wait several years for seedlings to reach reproductive maturity before their flowering type can be confirmed. The new genetic markers developed in the study make it possible to identify that trait while plants are still seedlings.

The researchers studied 153 avocado accessions and identified a 20-kilobase region on chromosome 10 associated with flowering behavior. The significant genetic markers within this region pointed to a single gene, named PaDSPD.

Avocado flowers open twice, first as female and later as male. In Type A cultivars such as Hass, the female stage occurs in the morning and the male stage the following afternoon. Type B cultivars follow the opposite timing. Having compatible flowering types in an orchard can support cross-pollination and fruit production.

DNA markers developed from the research successfully distinguished Type A from Type B plants in the material tested. This could help breeders select suitable plants earlier, plan crosses more efficiently and develop varieties with flowering characteristics that support better pollination and productivity. The researchers said further work is still needed to functionally validate the role of PaDSPD.

source: maxapress.com, usda.gov

photo: usda.gov