Cannabis Plant Biology, Genetics, and Cultivation Fundamentals
Plant biology essentials
Candidates should understand cannabis as a dioecious, photoperiod-sensitive flowering plant. Know the difference between photoperiod and autoflowering genetics, the roles of light cycle in triggering flowering (roughly 12 hours dark for photoperiod varieties), and the anatomy of the inflorescence including pistils, bracts, and trichomes. Understand trichome types (capitate-stalked, capitate-sessile, bulbous) and why capitate-stalked trichomes matter for cannabinoid and terpene content. Grasp the basics of photosynthesis, VPD (vapor pressure deficit), nutrient mobility, and the difference between macronutrients and micronutrients.
Genetics and breeding concepts
Understand genotype versus phenotype, the difference between a cultivar (clone-only) and a seed line, F1 hybrids, backcrossing, selfing (S1 lines), and the risks of inbreeding depression. Know how sex determination works, the value of feminized seeds, and why hermaphroditism is a cultivation risk. Familiarize yourself with common pests and pathogens (powdery mildew, botrytis, spider mites, russet mites) and integrated pest management principles, including the importance of avoiding banned pesticides.
Traps in questions
- Confusing genotype (genetic potential) with phenotype (expressed traits under environment).
- Assuming autoflowering plants require a light-cycle flip.
- Believing trichome color alone equals peak potency; it is a harvest-timing indicator, not a lab measurement.
- Overlooking that environmental stress can induce hermaphroditism and seed production.
Rule of thumb
Use the "genotype sets the ceiling, environment sets the expression" rule. Worked example: two clones from the same mother plant yield different cannabinoid profiles because one was grown under high VPD and heat stress; the correct interpretation is phenotypic variation from environmental factors, not genetic drift, since clones are genetically identical.