Diferenciação genética e diversidade em populações naturais de Cryptocarya aschersoniana Mez (Lauraceae)

Moraes, Pedro Luís Rodrigues de; Derbyshire, Maria Teresa Vitral de Carvalho

doi:10.1590/S1676-06032003000100008

Resumos

A variabilidade genética e estrutura de populações naturais de Cryptocarya aschersoniana Mez foram investigadas através de isoenzimas. Amostras de folhas de 267 indivíduos adultos foram coletadas de 12 populações procedentes de "Florestas de Planalto" do estado de São Paulo e sul de Minas Gerais, Brasil. A partir de 39 locos alozímicos polimórficos analisados, a divergência obtida através das estimativas de G ST sugerem a existência de deriva genética significativa e/ou de efeitos de seleção natural entre populações. O nível de diferenciação gênica (ĜST = 0,340) foi extremamente alto. A diversidade gênica dentro das populações (H S = 0,365) foi responsável por 66,12% da diversidade gênica total, indicando a existência de uma maior variabilidade ocorrendo dentro das populações do que entre as mesmas. Os testes de aderência ao Equilíbrio de Mutação e Deriva indicaram que nenhuma dessas populações encontra-se em equilíbrio. A partir da distância de Reynolds, verificou-se que as divergências entre os pares de populações foram também relativamente altas, sendo que poderiam estar associadas a efeitos de gargalo populacional devido à fragmentação florestal presente nas populações analisadas.

alozimas; Lauraceae; distância genética; variabilidade genética; diferenciação populacional; Neotrópico; Cryptocarya aschersoniana; Mata Atlântica; Brasil

The genetic variability and structure of natural populations of Cryptocarya aschersoniana Mez were investigated by means of isozymes. Leaf samples of 267 adult individuals were collected from 12 populations native of "Floresta de Planalto" of the State of São Paulo and Southern Minas Gerais State, Brazil. From 39 polymorphic allozyme loci analysed, the divergence obtained through G ST estimates suggests the existence of significant genetic drift and/or natural selectioneffects between populations. The level of gene differentiation ( ĜST = 0.340) was extremely high. The within sample gene diversity (H S = 0.365) account for 66.12% of the overall gene diversity, indicating a greater variability occurring within populations than among them. Goodness of fit tests for mutation-drift equilibrium showed that none of these populations was in equilibrium. From coancestry distance of Reynolds, divergences between pair of populations were also relatively high, which could be associated to bottleneck effects due to present forest fragmentation in analysed populations.

allozymes; Lauraceae; genetic distance; genetic variability; population differentiation; Neotropics; Cryptocarya aschersoniana; Atlantic Forest; Brazil

ARTIGO

Diferenciação genética e diversidade em populações naturais de Cryptocarya aschersoniana Mez (Lauraceae)

Pedro Luís Rodrigues de Moraes^I,II; Maria Teresa Vitral de Carvalho Derbyshire^I,III

^IBolsa de Pós-Doutoramento a P.L.R. Moraes (FAPESP 99/05004-5), auxílio à pesquisa (BIOTA/FAPESP 99/05818-2)

^IIDepartamento de Botânica,UNICAMP, Caixa Postal 6109, 13083-970, Campinas, SP, Brasil

^III Laboratório de Melhoramento de Plantas, CENA/USP, Caixa Postal 96, 13400-970, Piracicaba, SP, Brasil

^{Autor para correspondência} Autor para correspondência : Pedro Luís Rodrigues de Moraes E-mail: pmoraes@unicamp.br

RESUMO

A variabilidade genética e estrutura de populações naturais de Cryptocarya aschersoniana Mez foram investigadas através de isoenzimas. Amostras de folhas de 267 indivíduos adultos foram coletadas de 12 populações procedentes de "Florestas de Planalto" do estado de São Paulo e sul de Minas Gerais, Brasil. A partir de 39 locos alozímicos polimórficos analisados, a divergência obtida através das estimativas de G_ST sugerem a existência de deriva genética significativa e/ou de efeitos de seleção natural entre populações. O nível de diferenciação gênica (Ĝ_ST = 0,340) foi extremamente alto. A diversidade gênica dentro das populações (H _S = 0,365) foi responsável por 66,12% da diversidade gênica total, indicando a existência de uma maior variabilidade ocorrendo dentro das populações do que entre as mesmas. Os testes de aderência ao Equilíbrio de Mutação e Deriva indicaram que nenhuma dessas populações encontra-se em equilíbrio. A partir da distância de Reynolds, verificou-se que as divergências entre os pares de populações foram também relativamente altas, sendo que poderiam estar associadas a efeitos de gargalo populacional devido à fragmentação florestal presente nas populações analisadas.

Palavras-chave: alozimas, Lauraceae, distância genética, variabilidade genética, diferenciação populacional, Neotrópico, Cryptocarya aschersoniana, Mata Atlântica, Brasil.

ABSTRACT

The genetic variability and structure of natural populations of Cryptocarya aschersoniana Mez were investigated by means of isozymes. Leaf samples of 267 adult individuals were collected from 12 populations native of "Floresta de Planalto" of the State of São Paulo and Southern Minas Gerais State, Brazil. From 39 polymorphic allozyme loci analysed, the divergence obtained through G_ST estimates suggests the existence of significant genetic drift and/or natural selectioneffects between populations. The level of gene differentiation ( Ĝ_ST = 0.340) was extremely high. The within sample gene diversity (H_S = 0.365) account for 66.12% of the overall gene diversity, indicating a greater variability occurring within populations than among them. Goodness of fit tests for mutation-drift equilibrium showed that none of these populations was in equilibrium. From coancestry distance of Reynolds, divergences between pair of populations were also relatively high, which could be associated to bottleneck effects due to present forest fragmentation in analysed populations.

Key words: allozymes, Lauraceae, genetic distance, genetic variability, population differentiation, Neotropics, Cryptocarya aschersoniana, Atlantic Forest, Brazil.

Texto completo disponível apenas em PDF.

Full text available only in PDF format.

Recebido em 19/09/2002

Revisado em 02/04/2003

Publicado em 17/04/2003

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ASHTON, P.S. 1981. Techniques for the identification and conservation of threatened species in tropical forests. In The biological aspects of rare plant conservation (Synge, H., ed.). John Wiley & Sons, New York, p.155-164.
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BUSSAB, W.O., MIAZAKI, E.S. & ANDRADE, D.F. 1990. Introduçăo ŕ análise de agrupamentos. In Simpósio Nacional de Probabilidade e Estatística, 9, Săo Paulo, 1990. Associaçăo Brasileira de Estatística, Săo Paulo.
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CLEMENT, C.R., ARADHYA, M.K. & MANSHARDT, R.M. 1997. Allozyme variation in spineless pejibaye (Bactris gasipaes Palmae). Econ. Bot. 51:149-157.
COCKERHAM, C.C. 1969. Variance of gene frequencies. Evolution 23:72-84.
COCKERHAM, C.C. 1973. Analyses of gene frequencies. Genetics 74:679-700.
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HALL, P., WALKER, S. & BAWA, K.S. 1996. Effects of fo-rest fragmentation on diversity and mating systems in a tropical tree Pithecellobium elegans Conserv. Biol. 10:757-768.
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KIMURA, M. & CROW, J.F. 1964. The number of alleles that can be maintained in a finite population. Genetics 49:725-738.
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LUIKART, G. & CORNUET, J.-M. 1998. Empirical evaluation of a test for identifying recently bottlenecked popula-tions from allele frequency data. Conserv. Biol. 12:228-237.
MANLY, B.F.J. 1985. The statistics of natural selection on animal populations. Chapman and Hall, London.
MANTEL, N. 1967. The detection of disease clustering and generalized regression approach. Cancer Res. 27:209-220.
MARSHALL, D.R. & BROWN, A.H.D. 1975. Optimum sam-pling strategies in genetic conservation. In Crop genetic resources for today and tomorrow (Frankel, O.H. & Hawkes, J.G., eds.). Cambridge University Press, Cam-bridge, p.53-80.
MARUYAMA, T. & FUERST, P.A. 1985. Population bottle-necks and non-equilibrium models in population genet-ics. II. Number of alleles in a small population that was formed by a recent bottleneck. Genetics 111:675-689.
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Autor para correspondência

:

Pedro Luís Rodrigues de Moraes

E-mail:

pmoraes@unicamp.br

Datas de Publicação

Publicação nesta coleção
11 Jun 2013
Data do Fascículo
2003

Histórico

Aceito
17 Abr 2003
Revisado
02 Abr 2003
Recebido
19 Set 2002

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

[1] ALFENAS, A.C., PETERS, I., BRUNE, W. & PASSADOR, G.C. 1991. Eletroforese de proteínas e isoenzimas de fungos e essęncias florestais. Universidade Federal de Viçosa, Impr. Univ., Viçosa.

[2] ASHTON, P.S. 1981. Techniques for the identification and conservation of threatened species in tropical forests. In The biological aspects of rare plant conservation (Synge, H., ed.). John Wiley & Sons, New York, p.155-164.

[3] BATISTA, F., BAŃARES, A., CAUJAPÉ-CASTELLS, J., CARQUÉ, E., MARRERO-GÓMEZ, M. & SOSA, P.A. 2001. Allozyme diversity in three endemic species of Cistus (Cistaceae) from the Canary Islands: intraspecific and interspecific comparisons and implications for ge-netic conservation. Am. J. Bot. 88:1582-1592.

[4] BUSSAB, W.O., MIAZAKI, E.S. & ANDRADE, D.F. 1990. Introduçăo ŕ análise de agrupamentos. In Simpósio Nacional de Probabilidade e Estatística, 9, Săo Paulo, 1990. Associaçăo Brasileira de Estatística, Săo Paulo.

[5] CHAKRABORTY, R. & JIN, L. 1992. Heterozygote deficiency, population substructure and their implications in DNA fingerprinting. Hum. Genet. 88:267-272.

[6] CHASE, M.R., BOSHIER, D.H. & BAWA, K.S. 1995. Popu-lation genetics of Cordia alliodora (Boraginaceae), a neotropical tree. 1. Genetic variation in natural popula-tions. Am. J. Bot. 82:468-475.

[7] CLEMENT, C.R., ARADHYA, M.K. & MANSHARDT, R.M. 1997. Allozyme variation in spineless pejibaye (Bactris gasipaes Palmae). Econ. Bot. 51:149-157.

[8] COCKERHAM, C.C. 1969. Variance of gene frequencies. Evolution 23:72-84.

[9] COCKERHAM, C.C. 1973. Analyses of gene frequencies. Genetics 74:679-700.

[10] CORNUET, J.-M. & LUIKART, G. 1996. Description and power analysis of two tests for detecting recent popula-tion bottlenecks from allele frequency data. Genetics 144:2001-2014.

[11] CULLEY, T.M., WALLACE, L.E., GENGLER-NOWAK, K.M. & CRAWFORD, D.J. 2002. A comparison of two meth-ods of calculating G_ST, a genetic measure of population differentiation. Am. J. Bot. 89:460-465.

[12] DIAS, L.A.S. 1998. Análises multidimensionais. In Eletroforese de isoenzimas e proteínas afins: fundamentos e aplicaçőes em plantas e microrganismos (A.C. Alfenas, ed.). Editora UFV, Viçosa, p.405-475.

[13] FELSENSTEIN, J. 1985. Phylogenies from gene frequen-cies: a statistical problem. Syst. Zool. 34:300-311.

[14] FELSENSTEIN, J. 2002. PHYLIP: Phylogeny Inference Pack-age version 3.6a3. Department of Genetics, University of Washington, Seattle. (http://evolution.genetic s.washington.edu/phylip/phylip36.html)

[15] GOUDET, J. 1995. FSTAT (version 1.2): a computer program to calculate F-statistics. J. Hered. 86:485-486.

[16] GOUDET, J. 2002. FSTAT, a program to estimate and test gene diversities and fixation indices (version 2.9.3.2). Available from http://www.unil.ch/izea/softwares/fstat.html Updated from Goudet (1995).

[17] HALL, P., ORRELL, L.C. & BAWA, K.S. 1994. Genetic diver-sity and mating system in a tropical tree, Carapa guianensis (Meliaceae). Am. J. Bot. 81:1104-1111.

[18] HALL, P., WALKER, S. & BAWA, K.S. 1996. Effects of fo-rest fragmentation on diversity and mating systems in a tropical tree Pithecellobium elegans Conserv. Biol. 10:757-768.

[19] HARTL, D.L. & CLARK, A.G. 1989. Principles of population genetics. 2nd. ed. Sinauer Associates, Sunderland.

[20] KIMURA, M. & CROW, J.F. 1964. The number of alleles that can be maintained in a finite population. Genetics 49:725-738.

[21] LEE, S.-L., NG, K.K.-S., SAW, L.-G., NORWATI, A., SALWANA, M.H.S., LEE, C.-T. & NORWATI, M. 2002. Population genetics of Intsia palembanica (Leguminosae) and genetic conservation of Virgin Jungle Reserves in Peninsular Malaysia. Am. J. Bot. 89:447-459.

[22] LIENGSIRI, C., YEH, F.C. & BOYLE, T.J.B. 1995. Isozyme analysis of a tropical forest tree, Pterocarpus macrocarpus Kurz. in Thailand. For. Ecol. Manage. 74:13-22.

[23] LOVELESS, M.D. 1992. Isozyme variation in tropical trees: patterns of genetic organization. New For. 6:67-94.

[24] LOVELESS, M.D. & HAMRICK, J.L. 1987. Distribución de la variación en especies de árboles tropicales. Rev. Biol. Trop. 35:165-175.

[25] LOVELESS, M.D., HAMRICK, J.L. & FOSTER, R.B. 1998. Population structure and mating system in Tachigali versicolor, a monocarpic neotropical tree. Heredity 81:134-143.

[26] LUIKART, G., ALLENDORF, F.W., CORNUET, J.-M. & SHERWIN, W.B. 1998. Distortion of allele frequency dis-tributions provides a test for recent population bottle-necks. J. Hered. 89:238-247.

[27] LUIKART, G. & CORNUET, J.-M. 1998. Empirical evaluation of a test for identifying recently bottlenecked popula-tions from allele frequency data. Conserv. Biol. 12:228-237.

[28] MANLY, B.F.J. 1985. The statistics of natural selection on animal populations. Chapman and Hall, London.

[29] MANTEL, N. 1967. The detection of disease clustering and generalized regression approach. Cancer Res. 27:209-220.

[30] MARSHALL, D.R. & BROWN, A.H.D. 1975. Optimum sam-pling strategies in genetic conservation. In Crop genetic resources for today and tomorrow (Frankel, O.H. & Hawkes, J.G., eds.). Cambridge University Press, Cam-bridge, p.53-80.

[31] MARUYAMA, T. & FUERST, P.A. 1985. Population bottle-necks and non-equilibrium models in population genet-ics. II. Number of alleles in a small population that was formed by a recent bottleneck. Genetics 111:675-689.

[32] MEYER, D. 1996. Árvores evolutivas humanas - uma discussăo sobre inferęncia filogenética. Sociedade Brasileira de Genética, Série Monografias no. 3, Ribeirăo Preto, p. 1-162.

[33] MILLER, M.P. 1997. Tools for population genetic analyses (TFPGA) 1.3: a Windows program for the analysis of allozyme and molecular population genetic data. Com-puter software distributed by author. ( http://bioweb.usu.edu/mpmbio/tfpga.htm)

[34] MILLIGAN, B.G., LEEBENS-MACK, J. & STRAND, A.E. 1994. Conservation genetics: beyond the maintenance of marker diversity. Mol. Ecol. 3:423-435.

[35] MORAES, P.L.R. & DERBYSHIRE, M.T.V.C. 2002. Estrutura genética de populaçőes naturais de Cryptocarya aschersoniana Mez (Lauraceae) através de marcadores isoenzimáticos. Biota Neotropica 2: 19p. (http://www.biotaneotropica.org.br/v2n2/pt/fullpaper?bn02402022002+pt)

[36] MORAES, P.L.R. & MONTEIRO, R. 2002. Taxas de cruzamento em uma populaçăo natural de Cryptocarya moschata Nees (Lauraceae). Biota Neotropica 2: 10p. ( http://www.biotaneotropica.cria.org.br/v2n2/pt/fullpaper?bn01102022002+pt)

[37] MORAES, P.L.R., MONTEIRO, R. & VENCOVSKY, R. 2002. Genetic differentiation and diversity of natural popula-tions of Cryptocarya spp. (Lauraceae) from the Brazil-ian Atlantic rain forest. Lundiana 3:99-109.

[38] MYERS, N. 1988. Threatened biota: hotspots in tropical for-ests. Environmentalist 8:1-20.

[39] NEI, M. 1972. Genetic distance between populations. Am. Nat. 106:283-292.

[40] NEI, M. 1973. Analysis of gene diversity in subdivided popu-lations. Proc. Nat. Acad. Sc. USA 70:3321-3323.

[41] NEI, M. 1977. F-statistics and analysis of gene diversity in subdivided populations. Ann. Hum. Genet. 41:225-233.

[42] NEI, M. 1987. Molecular evolutionary genetics. Columbia University Press, New York.

[43] OHTA, T. & KIMURA, M. 1973. A model of mutation ap-propriate to estimate the number of electrophoretically detectable alleles in a finite population. Genet. Res. Cambr. 22:201-204.

[44] PIRY, S., LUIKART, G. & CORNUET, J.-M. 1999. BOTTLE-NECK: a computer program for detecting recent reduc-tions in the effective population size using allele fre-quency data. J. Hered. 90:502-503.

[45] REYNOLDS, J., WEIR, B.S. & COCKERHAM, C.C. 1983. Estimation of the coancestry coefficient: basis for a short -term genetic distance. Genetics 105:767-779.

[46] ROHLF, F.J. 1992. NTSYS: numerical taxonomy and multi-variate analysis system. Exeter Publishers, New York.

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