Chromosomal Sex Determination

Chromosomal sex determination refers to the genetic mechanism by which cannabis plants develop as male, female, or intersex individuals. Cannabis uses an XY sex chromosome system, where XX individuals typically develop as female and XY as male, though environmental stressors can trigger intersex expression in phenotypically female plants. Breeders and researchers study this system to understand sex stability, pollen production reliability, and the consistency of seed-producing females across generations. Lineage records and cultivation logs frequently document sex ratio anomalies tied to light cycles, temperature fluctuations, and nutrient imbalances, offering insight into how genetic predisposition interacts with growing conditions. This foundational knowledge underpins modern seed production, breeding selection for stable females, and the development of feminized seed lines.

Breeders working with chromosomal sex determination prioritize selecting stable, genetically female parents to reduce hermaphrodite expression in offspring. Understanding and stabilizing sex chromosomes is essential for producing reliable feminized seeds and maintaining true-breeding lines with predictable sexual phenotypes.