Sexual Expression

Sexual expression in cannabis genetics refers to the plant's phenotypic display of male, female, or hermaphroditic reproductive characteristics. This trait is genetically controlled and influenced by environmental factors including photoperiod, temperature stress, and nutrient availability. Understanding sexual expression is fundamental to breeding programs, as it determines seed production methods, breeding population stability, and crop planning. Cannabis exhibits genetic sex determination (typically XY systems in dioecious varieties), though environmental stress can trigger hermaphroditic flower production even in genetically female plants. Breeders carefully manage sexual expression to maintain reliable female-only lines for seed production or to intentionally create feminized seeds through controlled hermaphroditism.

Breeders select for stable female expression to ensure consistent feminized seed lines and reliable crop uniformity. Understanding the genetics and environmental triggers of sexual expression allows breeders to stabilize unstable lines, create deliberate hermaphrodites for seed production, and predict offspring ratios in breeding crosses.