Lucimara Cruz de Souza

Validação do marcador molecular ISSR para detecção de diversidade genética em Plathymenia reticulata Benth.

The species Plathymenia reticulata Benth., has great ecological potential being used for the reforestation of degraded areas, and the high economic value due to its wood of excellent quality. A technique to provide subsidies for conservation and management programs in this species, besides the use for studies of genetic diversity is the selection of molecular markers. Thus, the purpose of this study was the selection of primers ISSR (Inter Simple Sequence Repeat) to determine the genetic structure, as well as quantification of genetic diversity in a natural population of P. reticulata providing data for conservation and reforestation studies. The sample comprised 15 individuals in a forest fragment in the municipality of Guacui/ES, Brazil. Five primers were selected, which generated a total of 85 bands, of which 56 were polymorphic. It found high genetic diversity based on the values of Nei’s diversity index (H’ = 0.383) and Shannon index (I = 0.550). The number of genetic clusters obtained in the dendrogram by UPGMA corroborated with Bayesian’s analysis revealed two groups. ISSR were efficient and have identified the genetic diversity in the population sampled.

Research Article Genetic structure and diversity of Senefeldera verticillata (Euphorbiaceae) in semideciduous seasonal forest fragments

Senefeldera verticillata (Euphorbiaceae) is a species that exclusively occurs in the Atlantic Forest; it is used in the restoration and recovery of degraded areas and has therapeutic uses. Due to the scarcity of information on genetic patterns of this species, genetic diversity was characterized by the use of molecular markers, Inter Simple Sequence Repeats (ISSR). Leaf samples were collected from two populations located in the National Forest (FLONA) of Pacotuba and in the Private Reserve of Natural Patrimony (RPPN) Cafundo. Twelve ISSR primers were used, resulting in 179 amplification products, with 76% polymorphic bands. The genetic diversity values of Nei (H’) and Shannon index (I) were 0.329 and 0.503, respectively. The estimated historical gene flow among the fragments was high (Nm = 13.542). Molecular analysis of variance showed that most of the genetic diversity is within conservation units (95%), with genetic differentiation among populations considered moderate (ΦST = 0.0501). Thus we propose conservation of genetically dissimilar individuals in the two localities, so that the existing variability is preserved. Six groups were identified by the unweighted arithmetic means clustering method, in which 30 matrices of both fragments were collected in a single group. Bayesian analysis indicated that there is a small degree of genetic variation among populations, though organization of groups by locality was not confirmed by the STRUCTURE software. We were able to identify genetic divergence among the trees evaluated in these conservation units, demonstrating the usefulness of the ISSR markers. In addition, this information could help in the adoption of strategies for the selection of respresentative specimens to compose a seed bank of native forest species of the state of Espirito Santo