Key factors affecting seed germination of Copaifera langsdorffii, a Neotropical tree

Abstract

In natural conditions biotic and abiotic factors interact, synergistically affecting seed germination. In this study, we experimentally simulated natural conditions that occur during seed dispersal that can affect the germination of Copaifera langsdorffii. Specifically we evaluated the effect of aril removal by different dispersal agents (birds and ants) and fire on germination. The seeds were submitted to the following treatments: Control (seeds placed to germinate with aril intact); Acid (simulation of passage through the digestive tract of a bird); Aril removal (simulation of aril removed by ants); Fire (seeds exposed to fire). Germination percentage and time varied among treatments (X²=89. 735, P<0.001; X²=16.225, P<0.001, respectively). None of the control seeds (intact aril) germinated. Treatments that simulated dispersal (Acid, Aril removal) did not differ in germination percentage, with about 50% of the seeds germinating, however, the acid treatment accelerated seed germination. Fire also had a positive effect on seed germination with about 80% of the seeds germinating. Our results demonstrate the importance of dispersal agents to the population dynamics of C. langsdorffii. Furthermore, the capacity of seeds of C. langsdorffii to tolerate high temperatures is an important attribute for the occurrence of this species in the Cerrado.

Ants Promote Germination of the Tree Guarea guidonia by Cleaning its Seeds

“…Nevertheless, the number of dead seeds was lower than on the non-removal treatment, which suggests the importance of removing the sarcotesta of G. guidonia seeds in forest nurseries cultivating. Some studies conducted on other species showed improved germination on manually removed appendages compared to those not removed (Guimarães & Cogni, 2002;Passos & Oliveira, 2003;Christianini et al, 2007;Leal et al, 2007;Lima et al, 2013;Souza et al, 2015). These differences may have resulted from disinhibition effect induced by the aril or pulp removal, which is frequently higher than seed scarification and occurs in several species (Robertson et al, 2006).…”

Intraspecific variation in seed size and light intensity affect seed germination and initial seedling growth of a tropical shrub

“…This experimental design assumed each seed with their specific mass to be a statistically independent experimental unit, thus permitting comparisons of seed germinability among treatments (see Warton & Hui 2011;Souza & Fagundes 2014). Before sowing, all seeds were subjected to disinfection by immersion in a 1 % sodium hypochlorite solution for two minutes (Souza et al 2015). The humidity of the germination substrate was maintained daily by adding three milliliters of distilled water to each germination cell.…”

Modeling Ecological Niche of Tree Species in Brazilian Tropical Area

“…It has a large distribution range in South America, which includes areas from northern Argentina, southern Bolivia and the Brazilian Savanna (OLIVEIRA-FILHO; RATTER, 1995;RATTER et al, 2003). Moreover, the seed tolerance to high temperatures (SOUZA et al, 2015), its zoochoric dispersal (SEBBENN et al, 2011) and its shade tolerance (AQUINO; BARBOSA, 2009) corroborates with its wide geographic distribution.…”