Genetic diversity and structure of Podocarpus lambertii Klotzsch ex Endl. populations in the mixed ombrophilous forest of Santa Catarina state/ Diversidade e estrutura genetica de populacoes de Podocarpus lambertii Klotzsch ex Endl. na floresta ombrofila mista em Santa Catarina

• Published in: Ciência florestal 2019-01, Vol.29 (1), p.63
• Main Authors: Bittencourt, Ricardo, Steiner, Felipe, Sant'Anna, Cristina Silva, Montagna, Tiago, Fernandes, Caio Daros, da Silva, Fernando Andre Loch Santos, dos Reis, Mauricio Sedrez
• Format: Article
• Language: Portuguese
• ISSN: 1980-5098
• DOI: 10.5902/198050984449

Podocarpus lambertii (Podocarpaceae) is popularly known in Brazil as pinheiro-bravo. It occurs in several forest formations of the Atlantic Rain Forest, mainly in the Ombrophilous Mixed Forest. Due to the high wood exploitation suffered by the species, it is listed as 'Almost Threatened' in The IUCN Red List of Threatened Species. In face of this, the objective of the present study was to characterize the genetic diversity and structure of 12 natural populations of Podocarpus lambertii in Santa Catarina state, aiming to generate information for the definition of effective conservation strategies for the species. To access genetic diversity levels and distribution, it was used 10 allozymic systems. Along with the assistance of the software Fstat, the allelic frequencies (A), polymorphic loci percentage (P), observed heterozigosity ([H.sub.o]), expected heterozigosity, fixation index (f and genetic divergence between populations ([F.sub.ST]) were calculated. In 11 loci 32 alleles (A = 1,8) were detected. A low genetic diversity was detected for Podocarpus lambertii populations ([P.sub.100%] = 52,7; [H.sub.O] = 0,049; [H.sub.E] = 0,079). The mean fixation index obtained f = 0,374) indicates a deficit of heterozygous individuals. A high number of low frequency alleles was detected and together with the high genetic divergence ([F.sub.ST] = 0,303), it points towards the necessity of in situ conservation of a large number of Podocarpus lambertii populations and the need to increase the connectivity among the remnant populations. Keywords: Allozymes; Fixation index; In situ conservation; Conifer Podocarpus lambertii (Podocarpaceae) e conhecido popularmente como pinheiro-bravo. Ocorre em varias formacoes florestais da Mata Atlantica, principalmente na Floresta Ombrofila Mista. Devido a intensa exploracao madeireira sofrida pela especie, ela esta presente na categoria "Quase ameacada" da Lista Vermelha das Especies Ameacadas da IUCN. Diante disso, este estudo teve por objetivo caracterizar a diversidade e estrutura genetica de 12 populacoes no Estado de Santa Catarina, a fim de gerar informacoes para fundamentar estrategias de conservacao para a especie. Foram coletadas folhas de 50 individuos adultos em cada populacao. Para acessar os niveis e a distribuicao da diversidade genetica, utilizaram-se 10 sistemas enzimaticos. As frequencias alelicas, a porcentagem de locos polimorficos ([P.sub.100%]), as heterozigosidades observada ([H.sub.O]) e esperada ([H.sub.E]), o