Xy Chromosome System

The XY chromosome system is the primary sex-determination mechanism in Cannabis sativa, where males possess XY chromosomes and females possess XX chromosomes. This genetic framework directly influences plant morphology, flowering behavior, and reproductive capacity, making it foundational to breeding programs and cultivation strategies. Hermaphroditic expression—where plants develop both male and female reproductive organs—represents a deviation from typical XY/XX expression and is frequently studied in breeding contexts. Understanding sex chromosomes is essential for breeders working to stabilize dioecious (separate-sex) lines or develop feminized seed varieties. Environmental stress, genetic background, and specific allelic combinations can affect sex expression outcomes in offspring.

Breeders leverage XY chromosome knowledge to select for stable female lines, develop feminized seeds through sex reversal techniques, and maintain dioecious breeding stock for controlled pollination. Stable sex determination is critical for both commercial cultivation and genetic preservation programs.