PHYSICAL AND CHEMICAL PRETREATMENTS ON GERMINATION EFFICIENCY AND SEEDLING GROWTH OF Cannabis sativa

Seed dormancy in Cannabis sativa constrains large-scale cultivation and propagation by limiting uniform and rapid germination. This study evaluated the effects of physical and chemical seed pretreatments, including hot water soaking, nutrient priming, ultrasonication, microwave radiation, and selected conventional methods, on germination performance, seedling vigor, and phytochemical attributes. The methods assessed germination percentage, mean germination time (MGT), seedling length, biomass, seedling vigor index (SVI), total phenolic content (TPC), and antioxidant activity. The results revealed that ultrasonication for 20 min proved the most effective method overall, achieving 86.66% germination, an MGT of 2.84 days, and an SVI of 852.46. Hot water soaking produced the highest germination percentage (93.33%) but a lower SVI (284.32), while nutrient priming with potassium nitrate and calcium chloride resulted in the highest SVI (924.89) despite a longer MGT (4.57 days). Microwave pretreatment (15-20 min) significantly enhanced germination and phytochemical content, with 15 min yielding high antioxidant activity and 73.33% germination. Mechanical scarification, hydrogen peroxide, and dry heat were largely ineffective. Microwave treatment produced the highest TPC (9.22 ± 0.34 mg GAE g⁻¹). These results highlight several effective, scalable pretreatments for improving C. sativa propagation and bioactive compound potential. Keywords: dormancy; seed vigor; emergence; propagation; stress response.