Variation in the mating system of Bixa orellana L. (achiote) under three different agronomic systems

•Mating system (MS) varied between two phenotypes and among three agronomic systems.•A mixed MS in backyards and an outcrossing MS in mono- and poly-culture were found.•Maternal inbreeding coefficient varied from 0.18 to 0.49 (higher values in backyard).•Excepting the pink phenotype from polyculture, biparental inbreeding was ≈0.3.•Siring of seeds varied from 3 to 7, except the pink phenotype in polyculture (≈30).