Análisis evolutivo y genético de plantas parásitas del género Lophophytum

Se analizaron ocho genes de dos especies de lophophytum, L. mirabile y L. leandri. Dos genes permitieron evaluar las relaciones evolutivas de la familia balanophoraceae, que resultó ser polifilética, dividida en dos linajes independientes. Se identificaron cinco casos de genes mitocondriales foráneos en ambas parásitas, que fueron obtenidos de sus hospedadores leguminosas. Hibridaciones por Southern Blot mostraron una única copia de los genes foráneos cob y atp1 en Lophophytum mirabile. A partir de los análisis filogenéticos se infirió que la familia Balanophoraceae no forma un grupo monofilético y ambos linajes de esta familia forman parte del orden Santalales. El grupo hermano del género Lophophytum fue el género Ombrophytum. Se encontró evidencia de cinco genes mitocondriales foráneos adquiridos por transferencia horizontal en sentido hospedador-parásito. Dos de ellos sugieren transferencia funcional debido a que reemplazaron a los genes homólogos nativos y son genes universalmente presentes en las angiospermas.Fil: Wohlfeiler Altavilla, Josefina. Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales

Vernalization Requirement, but Not Post-Vernalization Day Length, Conditions Flowering in Carrot (Daucus carota L.)

Carrots require a certain number of cold hours to become vernalized and proceed to the reproductive stage, and this phenomenon is genotype-dependent. Annual carrots require less cold than biennials to flower; however, quantitative variation within annuals and biennials also exists, defining a gradient for vernalization requirement (VR). The flowering response of carrots to day length, after vernalization has occurred, is controversial. This vegetable has been described both as a long-day and a neutral-day species. The objective of this study was to evaluate flowering time and frequency in response to different cold treatments and photoperiod regimes in various carrot genotypes. To this end, three annual genotypes from India, Brazil, and Pakistan, and a biennial carrot from Japan, were exposed to 7.5 °C during 30, 60, 90, or 120 days, and then transferred to either long day (LD) or short day (SD) conditions. Significant variation (p < 0.05) among the carrot genotypes and among cold treatments were found, with increased flowering rates and earlier onset of flowering being associated with longer cold exposures. No significant differences in response to photoperiod were found, suggesting that post-vernalization day length does not influence carrot flowering. These findings will likely impact carrot breeding and production of both root and seed, helping in the selection of adequate genotypes and sowing dates to manage cold exposure and day-length for different production purposes.EEA La ConsultaFil: Wohlfeiler, Josefina. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria La Consulta; ArgentinaFil: Wohlfeiler, Josefina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Alessandro, Maria Soledad. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria La Consulta; ArgentinaFil: Morales Sanfurgo, Hugo Andres. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria La Consulta; ArgentinaFil: Cavagnaro, Pablo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria La Consulta; ArgentinaFil: Cavagnaro, Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Cavagnaro, Pablo. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias; ArgentinaFil: Galmarini, Claudio Romulo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria La Consulta; ArgentinaFil: Galmarini, Claudio Romulo. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Galmarini, Claudio Romulo. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias; Argentin

Numerous foreign mitochondrial genes in holoparasitic plants of the genus lophophytum

Las plantas parásitas forman una raíz modificada llamada haustorio, que conecta su tejido vascular con el dela planta hospedadora y permite el intercambio de nutrientes, agua e incluso RNA y ADN. La transferenciagénica horizontal (TGH) es la incorporación de material genético foráneo proveniente de otras especies. Elgenoma mitocondrial (mtDNA) de las angiospermas es particularmente susceptible a la transferencia degenes mitocondriales desde diversas plantas, aunque se conoce poco sobre el mecanismo y su impactoevolutivo. El objetivo de este trabajo es analizar el mtDNA de plantas holoparásitas de la familiaBalanophoraceae con el fin de comprender la dinámica, evolución, e incidencia de la TGH. La metodologíaincluyó la extracción de ADN total, amplificacion de genes mitocondriales por PCR y secuenciacion.Paralelamente, se realizó la secuenciación masiva de Lophophytum mirabile con la tecnología Illumina.Análisis filogenéticos demostraron una elevada incidencia de THG en L. mirabile. Aproximadamente el 70%de los genes en la mtDNA de L. mirabile fueron adquiridos de sus hospedadores leguminosas.Sorprendentemente, los genes foráneos han reemplazado a los genes nativos y son posiblemente funcionalesen L. mirabile.Fil: Sánchez Puerta, María Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; ArgentinaFil: Lijavetzky, Diego Claudio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; ArgentinaFil: Garcia, Laura Evangelina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; ArgentinaFil: Abbona, Cinthia Carolina. Universidad Tecnológica Nacional. Facultad Regional San Rafael. Instituto de Evolución, Ecología Histórica y Ambiente. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Evolución, Ecología Histórica y Ambiente; ArgentinaFil: Wohlfeiler Altavilla, Josefina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Mendoza-san Juan. Estación Experimental Agropecuaria la Consulta. Agencia de Extensión Rural la Consulta; ArgentinaFil: Ponce, Brenda Gabriela. No especifíca;Fil: Ceriotti, Luis Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; ArgentinaXXIV Jornadas de Investigación; VI Jornadas de Posgrado Universidad Nacional de CuyoMendozaArgentinaUniversidad Nacional de Cuyo. Secretaría de Ciencia, Técnica y Posgrad

Efficacy of Structural-Level Condom Distribution Interventions: A Meta-Analysis of U.S. and International Studies, 1998–2007

This systematic review examines the overall efficacy of U.S. and international-based structural-level condom distribution interventions (SLCDIs) on HIV risk behaviors and STIs and identifies factors associated with intervention efficacy. A comprehensive literature search of studies published from January 1988 through September 2007 yielded 21 relevant studies. Significant intervention effects were found for the following outcomes: condom use, condom acquisition/condom carrying, delayed sexual initiation among youth, and reduced incident STIs. The stratified analyses for condom use indicated that interventions were efficacious for various groups (e.g., youth, adults, males, commercial sex workers, clinic populations, and populations in areas with high STI incidence). Interventions increasing the availability of or accessibility to condoms or including additional individual, small-group or community-level components along with condom distribution were shown to be efficacious in increasing condom use behaviors. This review suggests that SLCDIs provide an efficacious means of HIV/STI prevention

Contact with HIV prevention services highest in gay and bisexual men at greatest risk: cross-sectional survey in Scotland

Background: Men who have sex with men (MSM) remain the group most at risk of acquiring HIV in the UK and new HIV prevention strategies are needed. In this paper, we examine what contact MSM currently have with HIV prevention activities and assess the extent to which these could be utilised further.Methods: Anonymous, self-complete questionnaires and Orasure (TM) oral fluid collection kits were distributed to men visiting the commercial gay scenes in Glasgow and Edinburgh in April/May 2008. 1508 men completed questionnaires (70.5% response rate) and 1277 provided oral fluid samples (59.7% response rate); 1318 men were eligible for inclusion in the analyses.Results: 82.5% reported some contact with HIV prevention activities in the past 12 months, 73.1% obtained free condoms from a gay venue or the Internet, 51.1% reported accessing sexual health information (from either leaflets in gay venues or via the Internet), 13.5% reported talking to an outreach worker and 8.0% reported participating in counselling on sexual health or HIV prevention. Contact with HIV prevention activities was associated with frequency of gay scene use and either HIV or other STI testing in the past 12 months, but not with sexual risk behaviours. Utilising counselling was also more likely among men who reported having had an STI in the past 12 months and HIV-positive men.Conclusions: Men at highest risk, and those likely to be in contact with sexual health services, are those who report most contact with a range of current HIV prevention activities. Offering combination prevention, including outreach by peer health workers, increased uptake of sexual health services delivering behavioural and biomedical interventions, and supported by social marketing to ensure continued community engagement and support, could be the way forward. Focused investment in the needs of those at highest risk, including those diagnosed HIV-positive, may generate a prevention dividend in the long term

From community to clients: the professionalisation of HIV prevention among gay men and its implications for intervention selection

Forces at work are described which encourage professionalisation and a reliance on one on one HIV prevention interventions among gay men. Community involvement is intrinsically linked to epidemic phases; when the threat diminishes, so does the community's ability to sustain community level interventions. The area of structural and environmental interventions, which can reinforce safe behaviour when community interest in collective action wanes, provides a potential complementary solution for prevention workers, researchers, and funders alike