Abstract Newly hatched caterpillars of the butterfly Heliconius erato phyllis routinely cannibalize eggs. In a manifestation of kin recognition they cannibalize sibling eggs less frequently than unrelated eggs. Previous work has estimated the heritability of kin recognition in H. erato phyllis to lie between 14 and 48%. It has furthermore been shown that the inheritance of kin recognition is compatible with a quantitative model with a threshold. Here we present the results of a preliminary study, in which we tested for associations between behavioral kin recognition phenotypes and AFLP and SSR markers. We implemented two experimental approaches: (1) a cannibalism test using sibling eggs only, which allowed for only two behavioral outcomes (cannibal and non-cannibal), and (2) a cannibalism test using two sibling eggs and one unrelated egg, which allowed four outcomes [cannibal who does not recognize siblings, cannibal who recognizes siblings, “super-cannibal” (cannibal of both eggs), and “super non-cannibal” (does not cannibalize eggs at all)]. Single-marker analyses were performed using χ2 tests and logistic regression with null markers as covariates. Results of the χ2 tests identified 72 associations for experimental design 1 and 73 associations for design 2. Logistic regression analysis of the markers found to be significant in the χ2 test resulted in 20 associations for design 1 and 11 associations for design 2. Experiment 2 identified markers that were more frequently present or absent in cannibals who recognize siblings and super non-cannibals; i.e. in both phenotypes capable of kin recognition.

Abstract Apple is a fruit crop cultivated worldwide. Apple orchards are exposed to a diverse set of environmental and biological factors that affect the productivity and sustainability of the culture. Many of the efforts and costs for apple production rely on reducing the incidence of fungal diseases, and one of the main diseases is apple scab caused by the fungus Venturia inaequalis. The economic impact of scab on apple productivity has guided many breeding programs to search for cultivars resistant to apple scab. Introgression from wild relatives has been successful to some extent, and genetic engineering for resistant cultivars has even been employed. This review presents the techniques used to the present time to obtain pathogen-resistant apple cultivars and introduces new biotechnological approaches based on plant plasmids that show promising results for delivering genetic traits with a short-term perspective.

The aim of this work was to evaluate the efficiency of real-time RT-PCR for detection of different isolates of ten important virus species that infect grapevines in Brazil: Grapevine leafroll-associated virus (GLRaV-1, -2, -3 and -5), Grapevine virus A (GVA), Grapevine virus B (GVB), Grapevine virus D (GVD), Grapevine rupestris stem pitting-associated virus (GRSPaV), Grapevine fleck virus (GFkV) and Grapevine fanleaf virus (GFLV). The reactions consisted of individual (simplex) and simultaneous (duplex) virus detections. Thirty six grapevine accessions, regenerated after thermotherapy and tissue culture treatments, have been analysed. All the above-mentioned viruses were sensitively detected in simplex reactions in samples infected with different virus isolates. Specifically to GLRaV-1 it was necessary to mix reagents refered by different sources to achieve the amplification. GVA, GRSPaV, GLRaV-2 and GLRaV-3 combined with GVB, GFLV, GFkV, GVD and GLRaV-5 were accurately detected in duplex trials. It was shown, that real-time RT-PCR (TaqMan) is able to efficiently detect different local virus species and isolates.

Aqui, é apresentado um método rápido e eficiente para obtenção de DNA de boa qualidade a partir de pequenas amostras de tecidos de artrópodos, gerando pequenas quantidades de resíduos perigosos. Comparamos a eficiência do método com outro protocolo caseiro utilizando fenol e com dois kits comerciais. A qualidade do DNA obtido foi verificada em espectrofotômetro e avaliada por um ensaio de AFLP. Foi obtido DNA pouco fragmentado a partir de todas as amostras, mas as melhores leituras foram obtidas para o DNA extraído com o novo método. O ensaio de AFLP indicou que os DNAs obtidos estavam adequados para uso em técnicas de biologia molecular sensíveis a contaminantes. Porém, os protocolos caseiros foram mais eficientes em extrair DNA do que kits comerciais, sem perder nenhuma qualidade na pureza das amostras. Além disso, eles foram mais rápidos e baratos, chegando a custar dez vezes menos que os kits comerciais. O protocolo mais rápido, menos poluente e mais barato foi o descrito aqui (USD 0,52 por amostra).

Here, it is presented a rapid and efficient method to obtain good quality DNA from small samples of arthropod tissues generating low quantities of hazardous wastes. This new method was compared with another homemade protocol using phenol and other two commercial kits. The quality of DNA obtained was checked by spectrophotometer and evaluated by an AFLP assay. Low shearing DNA was obtained from all samples and the best readings were observed to DNA recollected with the new method. The AFLP assay indicated that DNA obtained with all methods were suitable for use in molecular biology techniques sensitive to contaminants. However, homemade protocols were more efficient in recollect DNA than commercial kits, without lose any quality of samples. Also, they were less time and fund consuming, with costs ten times cheaper than commercial kits. The quicker, less pollutant and cheaper protocol was the one described here (USD 0.52 per sample).

A hipótese mais bem aceita atualmente para explicar a genética complexa da estenoespermocarpia, observada na videira, indica que a expressão deste fenótipo é controlada por três genes recessivos, independentemente herdados e controlados por um gene regulador dominante (sdI). Em estudo anterior, Lahogue et al. (1998) identificaram um marcador RAPD (Random Amplified Polymorphic DNA) ligado ao gene sdI e utilizaram-no para desenvolver um SCAR (Sequence Characterized Amplified Region) co-dominante denominado SCC8, que pode distinguir, em uma progênie, indivíduos com semente como também selecionar indivíduos apirênicos. Neste trabalho, são apresentados resultados da avaliação do potencial de aplicação do marcador molecular SCAR SCC8 para seleção assistida do caráter da apirenia no melhoramento de uvas de mesa sem sementes. A utilização deste marcador na seleção assistida para apirenia em uvas de mesa mostrou-se viável, e as conseqüências da sua utilização no programa de melhoramento da Embrapa Uva e Vinho são discutidas.

The inheritance of seedlessness in grapevine is based on a complex genetic system, where the expression of three independently inherited recessive genes is controlled by a dominant regulator gene (sdI). In a previous study, Lahogue et al. (1998) identified a random amplified polymorphic DNA marker, tightly linked to the sdI gene and developed a codominant SCAR (Sequence Characterized Amplified Region) marker named SCC8, that allows the distinction of seeded and seedless plants in a segregating progeny. The aim of the present work was to evaluate the usefullness of the SCAR marker SCC8 for assisted selection of the seedlessness character in grape breeding. According to our results, the use of the SCC8 marker is economically viable and the consequences of its use in the grapevine breeding program at Embrapa Uva e Vinho are discussed.