59º Congresso Brasileiro de Genética
Resumos do 59o$POHSFTTP#SBTJMFJSPEF(FOÏUJDBtBEFTFUFNCSPEF )PUFM.POUF3FBM3FTPSUt«HVBTEF-JOEØJBt41t#SBTJM XXXTCHPSHCS*4#/
77
GENETIC DIVERSITY AND mating SYSTEM IN A POPULATION OF Eugenia dysenterica DC. (Myrtaceae) BARBOSA, ACOF1,2; RODRIGUES, EB1,2; COLLEVATTI, RG2; GUEDES, LB2; SOARES, TN2; CHAVES, LJ3; TELLES, MPC2. 1
Programa de pós-graduação em Genética e Melhoramento de Plantas, Universidade Federal de Goiás (UFG) , Goiânia, GO; 2Laboratório de Genética & Biodiversidade, Instituto de Ciências Biológicas, UFG, Goiânia, GO; 3Escola de Agronomia, UFG, Goiânia, GO.
[email protected] Keywords: Cerrado, cagaita, inbreeding, microsatellite, outcrossing.
Eugenia dysenterica (Myrtaceae) is an endemic tree of the Brazilian Cerrado biome, widely distributed in savannas of the Central. In the last 60 years, the Cerrado biome was reduced to less than 50% of its original area, jeopardizing species long-term viability. Thus, understanding the genetic structure, gene flow and mating system in populations of E. dysenterica is essential for conservation planning. In this work we aimed to study the genetic diversity and mating system in a population of E. dysenterica using seven microsatellite loci. Almost 20 seeds were sampled from 20 adult trees (403 seeds) for DNA extraction and genotyping. Polymorphism (A = 21) and genetic diversity (He = 0.751), were high in the studied population. Multilocus outcrossing rate (tm = 0.934, SD = 0.028) was high and significant. However, inbreeding coeficient (f = 0.148) and biparental inbreeding (difference between the multilocus outcrossing and single locus outcrossing rates) were high and significant (tm – ts = 0.155), suggesting that the frequency of mating between closely related individuals is high. Paternity correlation was low (rp(m) = 0.161), suggesting that 16.1% of outcrossing sibs are sired by the same father and resulting in a mean number of pollen donors of 6.21 (Nep = 1/rp(m)). Our results also showed that 15% of the progenies analyzed, sired by cross-pollination are full sibs and 78.4% are half-sibs. Our results indicated that E. dysenterica has a predominantly outcrossing mating system in this population, which may maintain the high genetic diversity, despite the high inbreeding. Financial Support: CAPES, FAPEG, CNPq (475182/2009-0; GENPAC 10 - Proc. 563727/2010-1) and Systema Naturae Consultoria Ambiental.
