Análise da diversidade genética em populações de matamatá-amarelo (Eschweilera coriacea (dc.) S.a. Mori) utilizando marcadores microssatélites

Abstract

The matamatá-amarelo, Eschweilera coriacea (DC.)S.A. Mori, is a native forest species from rain forest mainly used for timberspecificallyfor producing mainstays, poles and fenceposts andalso ship factories. The species components are fungicide and antimicrobial and antioxidant chemicals. This work evaluated diversity and genetic structure of natural populations of E. coriacea, using ninemicrosatellite loci developedthrough an enriched genomic library. Of the 96 positive clones sequenced, 81 contained repetitive sequences, of which 49 (65%) were appropriate for design of primers in the flanking regions and 24 sequences were selected for primer pair design using the Software Primer 3. Twelve microsatellite primersamplifiedand were polymorphic, being nine used to estimategenetic parameters of six populations of matamatá-amarelo as follows: Highway BR-429, Rondônia-RO (n=31), Federal University of AmazonasState(UFAM) -Manaus-AM (n=36), Adolpho Ducke Reserve, Manaus-AM (n=32), Experimental Farm of the Federal University of AmazonasState(UFAM), Coari-AM (n=33), Santa Helena Farm and Ilha de Vera Cruz, Maués-AM (n=35) and Vila Amazônia, Parintins-AM (n=35). There is a great genetic variability for the genotypes of E. coriacea, with mean of 16,2 allelesper loci andtotal diversity(HT) equal to0,77. Nine loci presented 14 common alleles and 30 intemediate-frequency alleles, 102allelesscattered among population, being 41 private, 47 sporadical and 14 spread out. The observed estimates ofheterozygosity (HO) were smaller than 0,5 for most loci,varying from 0,07 (Ec15) to 0,75 (Ec36). The expected estimates of heterozyigosity(HE) varied from 0,13 (Ec15) to 0,92 (Ec24). The values of HOwere smaller than the values of HEin most loci, except lociEc37 in Rondôniapopulation. Differences between HOand HEfor most loci indicate deficiency of heterozygote. The Fischer test showed that 85,2% of loci do not join the HWEthe populations. The coefficients of inbreeding(f) varied between populations, being largerinDuckeReserve (0,53) andsmaller inUFAM (0,29), with mean of0,4, showing inbreeding in populations. The number of alleles for all loci was larger for the Maués population (105) and smaller in Rondônia (54). The high index for diversity estimated byHEe HOwere similar to most populations, varying between 0,33/0,44 (HO/HE) and 0,46/0,83 (HO/HE), being the HOsmaller in Rondônia population and larger in UFAM and Parintins andHEsmaller in theRondôniapopulation and larger forMaués. The AMOVA xix

detected 87,5% of total variation inside populations and 12,5%. Genetic differentiation was detected (FST) between populations of Parintins and Maués (0,018),followed by UFAM andDucke Reserve (0,030), certainly dueto the high gene flow(Nm=13,4; 8,1, respectively). This relation was confirmed by dendrogram of genetic distances of NEI (1978), which shows two groups, one formed by formed by UFAM/Reserva Ducke and Parintins/Maués populations, followed by Rondônia andCoari, asdetected bythe STRUCTURE Program.The Mantel test showed relation between geographic and geneticdistance, showing distance isolation. The results indicate that nine microsatellite loci were efficient in evaluating geneticdiversity in six populations ofE. coriacea, showing that most genetic variation is found inside populations and the mild genetic structure was found between populations, being explained by distance isolation, possibly associate to mating patterns and population demography.