Fine-scale spatial genetic structure study in contrasting landscapes as a tool for make management decisions in native forests: the case of cebil

ESCALADA, MICAELA CAROLINA; GONCALVES, ALEJANDRA LORENA; GARCÍA, MARÍA VICTORIA; BARRANDEGUY, MARÍA EUGENIA

Posadas

Conferencia; IUFRO Conference: Adaptive Management for Forested Landscapes in transformation; 2018

International Union of Forest Research Organizations

Fine-scale spatial genetic structure (FSGS) in plants is mainly determined by the pollen and seed dispersal, which is strongly affected by both evolutionary and ecological processes. FSGS studies in forest tree species allow evaluating the influences of landscape configuration on pollen and seed movement. Here, we compared FSGS among natural populations of a native forest tree species Anadenanthera colubrina var. cebil, locally known as cebil. Populations are localized in Santa Ana (SA) (Paranaense phytogeographic province) and Calilegua National Park (CL) (Yungas phytogeographic province). SA population is located in a highly fragmented landscape in contrast to the relatively continuous landscape where CL population is located. Eight specific microsatellite markers were used to genotype 68 adult individuals. FSGS was evaluated based on pairwise kinship coefficients (Fij) at different distance classes. Fij was positive and significantly different than expected at random only at first distance class (up to 154m) in CL population. In SA population fragments, the kinship was significantly different than expected at random in the most of distance classes. In this sense, FSGS of SA was higher and stronger rather than FSGS of CL (F1(SA)=0.077 and F1(CL)=0.044; Sp(SA)=0.022 and Sp(CL)=0.016). These results might be explained by restricted dispersal that generates familiar units and spatial structure at the patch level in SA. The inbreeding coefficient was markedly higher in SA than CL (FIS=0.34 and 0.15, respectively) as a consequence of an increase in the levels of mating between relatives within patches in the fragmented landscape. The results of this work are relevant to make management decisions, being ~154m a minimal distance of forested landscapes needed to maintain genetic connectivity among natural populations of A. colubrina var. cebil.