Ex-situ conservation: Seed storage strategies for Monimiaceae (Laurales) species in the Atlantic Forest

Abstract

The Atlantic Forest is one of the world's hotspots, being a center of diversity for several plant groups, including Monimiaceae, however, this high diversity is under intense pressure. The species Grazielanthus arkeocarpus and Mollinedia ovata of the Monimiaceae are found in the Biological Reserve of Poço das Antas, in Rio de Janeiro state, where fires threaten the existence of these individuals. Furthermore, G. arkeocarpus is critically endangered and microendemic. Therefore, implementing initiatives aimed at the ex situ conservation of these species is of utmost importance. The present study's objective was to analyze seed storage behavior of the species to conserve in seed banks. Mature fruits were collected and benefited, and the seeds were conducted for completely randomized experiments. The seeds were divided into three batches: fresh seeds (control), with 30%, and 10% water content (WC). Then, each batch was stored for five days at temperatures of 20, 10, and 20 ºC. Germination tests were conducted at temperatures of 20 and 15/25 ºC for 30 days, and the viability of ungerminated seeds was checked. Statistical analyses were performed using GLM with the Binomial model in R Software. Fresh seeds of G. arkeocarpus and M. ovata have a water content of 57% ± 2.5 and 58% ± 2.5, respectively. The G. arkeocarpus batch with 10% WC presented zero germination at all storage temperatures, but the viability percentage was above 80% when stored at 20 and 10 °C, indicating the presence of primary dormancy. In contrast, the M. ovata batches with 30% and 10% WC obtained relatively high percentage germination, above 60%. The data demonstrate that the seeds of both species are orthodox and can be stored in seed banks for the ex situ conservation of these species.

Keywords: Seed banks, Germination, Endemism, Orthodox