Development and transferability of microsatellite markers for a complex of Aspidosperma Mart. & Zucc. (Apocynaceae) species from South American Seasonally Dry Tropical Forests

Abstract

In this study, we developed and characterized microsatellite for Aspidosperma pyrifolium Mart. & Zucc., considered a species complex due to its morphological variation and disjunct distribution. This complex is predominant in the Caatinga of Northeast Brazil, but also occurs in semi-deciduous seasonal forests of central Brazil, in Chaco areas of the southwestern Brazil, Bolivia and Paraguay. These vegetations are included in the concept of Seasonally Dry Tropical Forests (SDTFs). SDTFs are considered one of the most endangered forests in the world due to intense anthropic pressure and high endemism. Concerning endemic species of SDTFs, little is known about the genetic structure of A. pyrifolium and the effects of disjunct distribution on their gene flow and genetic diversity. In this study, 16 polymorphic and four monomorphic microsatellites were characterized in 82 Aspidosperma pyrifolium individuals from three populations in Brazil's Northeast. The transferability resulted in an average of seven markers, amplified in 11 other species of the genus (A. brasiliense A.S.S. Pereira & A.C.D. Castello, A. illustre (Vell.) Kuhlm. & Piraja, A. inundatum Ducke, A. multiflorum A.DC., A. nobile Mull.Arg., A. polyneuron Mull.Arg., A. quebracho-blanco Schltdl., A. ramiflorum Mull.Arg., A. rigidum Rusby, A. schultesii Woodson and A. subincanum Mart.). These markers can be used to estimate genetic parameters and help us to better understand the boundaries within A. pyrifolium complex. Their use can also be extended for conservation purposes of A. pyrifolium populations and consequently of SDTFs. Moreover, they may be applied in studies concerning other species of the genus.