Growth Hormone Sensitivity

Growth hormone sensitivity refers to a plant's genetic predisposition to respond to endogenous and exogenous auxins and gibberellins during vegetative and flowering phases. This classification describes variation in internode spacing, stem elongation rates, and overall plant architecture across cannabis genotypes. Some lineages express compact, dense growth patterns with tight nodal spacing, while others display more open, stretched morphologies—traits often linked to specific cultivar backgrounds and environmental conditions. Understanding growth hormone sensitivity helps breeders predict plant structure outcomes and select parents for desired canopy architecture. This characteristic is distinct from photoperiod response and is controlled by multiple genetic loci affecting hormone regulation pathways.

Breeders working in controlled-environment agriculture prioritize growth hormone sensitivity when selecting for efficient space utilization, branching patterns, and yield structure. Selecting for compact phenotypes or controlled stretch allows optimization of lighting systems and crop density in indoor operations.