Phenotyping

Phenotyping refers to the observable physical and chemical characteristics expressed by a cannabis plant, determined by the interaction of its genetic material (genotype) and environmental conditions. In cannabis breeding, phenotyping encompasses plant structure, leaf morphology, terpene profiles, cannabinoid ratios, flowering time, and yield characteristics. Breeders identify and document distinct phenotypes within seed populations to stabilize desirable traits across generations. Phenotypic variation within a single genetic line can be significant, making consistent phenotype selection essential for creating stable, reproducible cultivars. Understanding phenotype expression helps breeders distinguish true-breeding lines from unstable crosses and informs decisions about which plants to retain for future breeding work.

Selective phenotype identification and stabilization is fundamental to cannabis breeding programs. Breeders regularly phenotype test crosses and use phenotypic markers—growth rate, resin production timing, plant architecture—to accelerate selection toward target cultivars.