Genetic structure of populations of Pissodes castaneus (De Geer) (Coleoptera, Curculionidae) using amplified fragment length polymorphism. The objective of this study was to determine the genetic structure of populations of Pissodes castaneus from different areas and on different species of Pinus using the PCR-AFLP technique. Twenty samples were analyzed, representing 19 populations from Brazil and one from Florence, Italy, which is the region of origin of P. castaneus. The four combinations of primers generated a total of 367 fragments of DNA, and 100% of polymorphic loci, indicating high degree of molecular polymorphism. The dendrogram did not reveal trends for grouping the populations in relation to origin. The low genetic similarity (0.11 between the most distant groups) and genetic distances of 0.13 and 0.44 for 10 out of the 20 samples may indicate several founding events or multiple introductions of heterogeneous strains into Brazil. The allelic fixation index (Fst) was 0.3851, considered high, and the number of migrants (Nm) was 0.3991, indicating low gene flow among populations. The highest genetic distances were between the population from Irani, SC and Cambará do Sul, RS and Bituruna, PR, indicating an independent founding event or a particular allelic fixation in the former location. The high genetic diversity among populations points out that the populations are genetically heterogeneous with a diverse gene pool in the surveyed areas, what makes them to respond differently to control measures.

Dentre as 130 espécies de afídeos registradas para o Brasil, a maioria é exótica com origem em regiões temperadas. O objetivo desta pesquisa foi o estudo das espécies de afídeos que ocorrem em diferentes altitudes no ecossistema rico em diversidade da Mata Atlântica. Onze pontos de coleta foram amostrados em um gradiente altitudinal de -10 a 1000 m s.n.m. na Serra do Mar, no estado do Paraná com armadilhas amarelas de água e coletas nas plantas no decorrer de um ano. Um total de 87 espécies de afídeos foi coletado em armadilhas e em plantas. O maior número de espécies foi encontrado em áreas de transição ou ecótone definidos pela sobreposição de comunidades diferentes de plantas. Aphis spiraecola Patch, 1914 foi a espécie mais abundante registrada em todos os locais amostrados. O pico populacional ocorreu, principalmente, no mês de setembro quando as plantas estavam em brotação. Não foi observado um padrão altitudinal na distribuição dos afídeos na Serra do Mar, porém algumas espécies foram registradas em altitudes específicas. Condições climáticas, além de outros fatores bióticos e abióticos, afetam a flutuação populacional dos afídeos, porém não foi possível estabelecer uma correlação entre a ocorrência dos insetos com a temperatura e precipitação.

There are about 130 species of aphids registered for Brazil and most of them are exotic, originated from temperate regions. The objective of this research was to survey the aphid species that occur in different altitudes in the rich and diverse ecosystem of the Atlantic Rain Forest. The area surveyed included 11 collecting points ranging from -10 to 1000 m a.s.l. in Serra do Mar, in Paraná State, using yellow pan traps and plant collection, during one year. A total of 87 aphid species were collected in the traps and plants. The richness of species was noticeable high in transitional areas, where different plant communities overlapped. The most abundant aphid species was Aphis spiraecola Patch, 1914, in every collecting place. Population peaks occurred mainly in September when most plants showed new shoots. It was not observed an altitudinal gradient pattern of aphid distribution in the Serra do Mar, but some species were found to be restricted to specific altitudes. It is known that climate, besides other biotic and abiotic factors, affect aphid population fluctuation, but no correlation was established with temperature and rain fall.