Comparison of Seed Germination and Seedling Growth Parameters in Canarium strictum Roxb. under Different Treatment Combinations

Abstract

The experiment was conducted during March to July, 2025, in a factorial randomized block design with three replications to study the effect of different pre-sowing treatments, including KNO₃ (1% and 1.5%) and H₂O₂ (3% and 5%), and moisture content levels, including initial (12%) and reduced moisture content (10% and 8%), on seed germination and initial growth parameters of seedlings. Canarium strictum Roxb., commonly known as black dammar, is a highly valued and socio-economically important semi-evergreen tree species. However, the natural regeneration of this species is poor due to the hard outer pericarp for germination. The significance of moisture content and pre-sowing treatments in regulating physiological and metabolic activities associated with germination is well-established. The maximum value for germination parameters was recorded at IMC (12%), while the minimum was at RMC (8%). Among the pretreatments, the maximum value for germination parameters was recorded for KNO₃ at 1% concentration, while the minimum was observed in the control. With respect to initial seedling growth parameters, the maximum value was observed under reduced moisture content at 10% when seeds were treated with KNO₃ at 1% concentration. In conclusion, the findings highlight that IMC (12%) and RMC (10%), along with pre-sowing treatment of KNO₃ at 1% concentration, stand out as optimal ranges for ensuring the highest germination percentage, seedling vigor, and uniformity in Cannarium strictum seedlings. The authors argue that artificial regeneration via nursery propagation using treated seeds could significantly boost seedling establishment and offset poor natural recruitment.