Sex Determination

Sex determination in cannabis refers to the genetic and environmental mechanisms that establish whether a plant develops as male, female, or hermaphrodite. Cannabis is typically dioecious, meaning plants produce either pollen-bearing male flowers or seed-bearing female flowers, though environmental stress can trigger hermaphroditic expression in genetically female plants. Understanding sex determination is foundational to breeding programs, as controlled pollination depends on reliably identifying and isolating plants by sex. Photoperiod, temperature fluctuations, and nutrient imbalances are commonly associated with influencing sex expression, particularly in photoperiodic cultivars. Breeders working with autoflowering and feminized seed lines have developed selection protocols specifically targeting stable sex expression across generations.

Breeders prioritize sex stability when developing commercial seed lines and cultivars intended for uniform crops. Selecting parent plants with consistent female expression under varied conditions helps reduce hermaphrodite offspring and improves seed reliability across diverse growing environments.