Germinação e produção de bomba de semente de Castanha-da-Amazônia como potencial para reflorestamento

Abstract

Seed bomb production has emerged as a promising and low-cost technique for reforestation, particularly in degraded or hard-to-access areas. This approach consists of encapsulating seeds within clay spheres combined with different substrates, providing protection and favorable conditions until germination begins. This study aimed to produce and evaluate seed bombs containing Brazil nut (Bertholletia excelsa), a species of high ecological and socioeconomic importance, assessing germination efficiency across different substrate compositions. Three treatments were tested, combining clay and black soil with the following materials: vermiculite (T1), commercial garden substrate (T2), and cured cattle manure (T3). The seeds were previously stratified in moist substrate to overcome dormancy. The experiment followed a completely randomized design with 48 seed bombs, and evaluations were conducted every 12 days over a 60-day period, analyzing germination rate, seedling height, and number of leaves.The results showed that Treatment 1 presented the highest germination rate (75%), highlighting the efficiency of vermiculite due to its high water-retention capacity. Treatments 2 and 3 achieved germination rates of 50% and 44%, respectively. However, for the variables height and number of leaves, no statistically significant differences were observed between the treatments, indicating that all substrates were able to support the initial development of seedlings in a similar way. These findings confirm the viability of the seed bomb technique for the propagation of the Brazil nut tree, while also demonstrating flexibility regarding the use of different substrates or the need to evaluate the experiment over a longer period and with new treatments. It is concluded that the technique showed, in this initial study, potential for application in ecological restoration programs in the Amazon, contributing to the recovery of degraded areas through accessible, efficient, and easy-to-implement methods.