Paternity analysis based on eight microsatellite loci was used to investigate pollen and seed dispersal patterns of the dioecious wind-pollinated tree, Araucaria angustifolia. The study sites were a 5.4 ha isolated forest fragment and a small tree group situated 1.7 km away, located in Parana State, Brazil. In the forest fragment, 121 males, 99 females, 66 seedlings and 92 juveniles were mapped and genotyped, together with 210 seeds. In the tree group, nine male and two female adults were mapped and genotyped, together with 20 seeds. Paternity analysis within the forest fragment indicated that at least 4% of the seeds, 3% of the seedlings and 7% of the juveniles were fertilized by pollen from trees in the adjacent group, and 6% of the seeds were fertilized by pollen from trees outside these stands. The average pollination distance within the forest fragment was 83 m; when the tree group was included the pollination distance was 2006 m. The average number of effective pollen donors was estimated as 12.6. Mother-trees within the fragment could be assigned to all seedlings and juveniles, suggesting an absence of seed immigration. The distance of seedlings and juveniles from their assigned mother-trees ranged from 0.35 to 291 m (with an average of 83 m). Significant spatial genetic structure among adult trees, seedlings, and juveniles was detected up to 50 m, indicating seed dispersal over a short distance. The effective pollination neighborhood ranged from 0.4 to 3.3 ha. The results suggest that seed dispersal is restricted but that there is longdistance pollen dispersal between the forest fragment and the tree group; thus, the two stands of trees are not isolated.

As a matter of fact, Araucaria angustifolia populations occur predominately in small and isolated stands; only a minor number of continuous natural forests of this dioecious wind-pollinated coniferous tree species remain. To implement reasonable conservation, breeding and restorations program it is necessary to have the knowledge of pollen dispersal distance and fine-scale genetic structure. In this paper, levels and dispersion distance of pollen and spatial genetic structure of A. angustifolia were investigated in a 14 ha transect in a continuous forest in Paraná State, Brazil. Analyses have been performed by the use of eight microsatellite loci, paternity and TWOGENER approaches, and spatial autocorrelation analysis. In transect, 52 male and 56 female adult trees were mapped and genotyped, together with 190 seeds. In the present transect, A. angustifolia show spatial genetic structure at distances up to 75 m. Paternity analysis indicated that 54% of seeds were fertilized by pollen from trees outside the transect. The calculated average pollination distance within transect was 102 and 98 m based on the paternity analysis and TWOGENER analysis, respectively. We found a significant pollen gene pool structure across seed-trees ( b U ft ¼ 0:078, P \ 0.01) that corresponds to an effective number of pollen donors of 6.4 male trees or an effective pollination neighbourhood area (A ep ) of 2.1 ha. The findings suggest long-distance pollen dispersion ([100 m) inside the continuous forest. However, the high proportion occurs in short-distance producing biparental and correlated mating as well as reducing the variance effective size.

Bacillus cereusis an ubiquitous, spore-forming bacteria that can survive pasteurization and the majority of the heating processes used in the dairy industry. Besides, it is a pathogen responsible for different types of food poisoning. One type of foodborne disease caused by B.cereusis the diarrheal syndrome, which is caused by the ingestion of vegetative cells producing toxins in the small intestine. One virulence factor for the diarrheal syndrome is the toxin hemolysin BL (HBL), a three-component protein formed by the L1, L2 and B components. In order to evaluate the presence of diarrheal strains isolated from milk and dairy products, 63 B. cereus isolates were obtained from 260 samples of UHT milk, pasteurized milk and powdered milk, sold in commercial establishments and from different brands. The isolates were subjected to the Polymerase Chain Reaction (PCR) for the detection of the encoding genes for the L1, L2 and B components and the toxin production capacity were evaluated with an immunoassay. A total of 23 [36.5%] isolates were identified carrying simultaneously the three tested genes, from which, 20 [86.9%] showed toxigenic capacity. 26 [41.3%] isolates did not carry any of genes tested and the other 14 [22.2%] were positive for one or two of them. The results showed a high toxigenic capacity among the B. cereus isolates able to produce the HBL, indicating a potential risk for consumers.

Araucaria angustifolia is an endangered tropical/ subtropical coniferous of great interest for conservation due its economical, ecological, and social value. Only 3% of original Araucaria forests remain, which are generally confined to small forest fragments. Forest fragmentation can have serious consequences on genetic process in tree population, affecting long-term fitness and adaptability. To investigate the effects of forest fragmentation on genetic diversity and the structure of A. angustifolia populations, the genetic diversity of eight microsatellite loci was compared in four small fragmented populations (<22 ha), four tree groups (five to 11 trees) occurring in pastures and in three plots in a large continuous population. The clearest effect of fragmentation was the loss of rare alleles (p≤0.05) in fragmented populations (19.4% to 47.2%) and intermediate frequency (0.05

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O presente trabalho teve por objetivo adaptar o protocolo descrito por Soto (2001), testar diferentes fontes (tecido vegetal) e estabelecer condições de coleta e pré-tratamento de amostras para extração de DNA de jabuticabeira (Plinia cauliflora (DC.) Berg, Myrtaceae). Utilizaram-se folhas em desenvolvimento, folhas completamente expandidas, câmbio do caule e pecíolo foliar. O protocolo testado pode ser utilizado para extração de DNA de jabuticabeira, pois proporcionou isolamento de DNA de boa qualidade e possibilitou amplificação por meio de PCR ("Reação de Polimerase em Cadeia"). Para evitar a oxidação de folhas é necessário realizar a maceração com nitrogênio líquido.

Maytenus ilicifolia é um arbusto de ocorrência natural da Floresta Ombrófila Mista (Floresta com Araucária). Esta espécie tem uso popular em comunidades tradicionais e povos indígenas no Brasil. A fragmentação da Floresta com Araucária, nas últimas décadas, juntamente com a comprovação terapêutica em males gástricos e o uso em larga escala, causaram grande devastação de populações naturais de Maytenus ilicifolia, resultando na perda do complexo genético deste recurso medicinal. Há necessidade urgente de estudos para elaborar estratégias de conservação genética e domesticação deste germoplasma. O objetivo deste estudo foi determinar a variabilidade genética em populações naturais Maytenus ilicifolia por meio da análise do polimorfismo de DNA utilizando marcadores RAPD. Três populações foram estudadas, uma no município da Lapa e duas na região de Guarapuava. Estas áreas são distintas, tanto geologicamente quanto em relação a paisagem. Selecionou-se sete primers RAPD, os quais produziram 52 bandas em Maytenis ilicifolia, sendo 44 polimórficas. A análise da distância genética foi realizada pelo agrupamento das amostras segundo os princípios da taxonomia numérica, utilizando-se o coeficiente de similaridade de Jaccard. A partir das distâncias genéticas, montou-se um dendrograma, o qual separou o material estudado em quatro grupos distintos, dois para a região da Lapa e dois para Guarapuava. Os grupamentos formados estão arranjados de acordo com as características geológicas e classes de solos em que os indivíduos se encontram. A variabilidade genética das populações de Guarapuava, quando comparada a da Lapa, apresentou uma maior similaridade entre os grupos formados. Estratégias para conservação genética em Maytenus ilicifolia devem ser estruturadas de acordo com os parâmetros ecogeográficos locais, realizando a coleta em cada um dos compartimentos ambientais em que os indivíduos se encontram.

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