Alternative substrates and shading in the initial development of Croton lechleri seedlings

Croton lechleri (dragon's blood) is a forest species used by traditional Amazonian communities for medicinal purposes, with potential for use in degraded area recovery and as a source of additional income for some communities. However, silvicultural studies on this species are scarce. This study aimed to evaluate the influence of substrates and shading levels on seedling emergence and initial development of C. lechleri seedlings. A completely randomized statistical design with four replications was used, arranged in a 7 x 5 factorial setup (substrates and shading levels). The variables analyzed were seedling emergence, emergence speed index, relative emergence frequency, root and shoot length, root and shoot dry mass, stem diameter, and leaf count. Alternative substrates composed of carbonized rice husk and commercial substrate at all shading levels studied favored the emergence and emergence speed index of C. lechleri seedlings. In the 80% shade environment, the substrate consisting of forest topsoil + aged chicken manure (3:1) proved suitable for post-emergence seedling development of C. lechleri.