Direct Seeding Using Seed Briquette and Dormancy-Breaking Treatments on the Tropical Tree Species in Indonesia

Direct seeding has been practiced in reforestation for a long time and it is claimed to be low-cost and easy to apply. However, the technique’s implementation success is still questionable. Adaptive species, optimal seed treatment, and the right delivery system will certainly increase the success of direct seeding. This study aimed to assess the early establishment performance of 24 tropical tree species for direct seeding using seed briquettes and dormancy-breaking. A randomized block design with 3 blocks was used to assess the seedling survival and growth of 24 tropical species. Seed briquette and dormancy-breaking treatments had a significant effect on the seedling survival, except for Falcataria falcata, Lagerstroemia speciosa, Leucaena leucocephala, Maesopsis eminii, Nauclea orientalis, Ochroma pyramidale, and Sindora velutina. Seed briquette provided a high seedling survival (>50%) on Swietenia macrophylla, Calophyllum inophyllum, Enterolobium cyclocarpum, Pometia pinnata, and Hymenaea verrucosa. Seed weight, length, width, and germination were positively correlated with seedling survival, with correlation coefficients (r2) of 0.686, 0.729, 0.762, and 0.670, respectively. The use of seed briquettes composed of compost, soil, charcoal, lime, and tapioca, with a dormancy-breaking treatment, can increase the success of direct seeding in tropical areas, thereby directly impacting Sustainable Development Goal 15 (Life on Land).