176 research outputs found

    Diversity and Abundance of Hymenopterous Parasitoids Associated with Anastrepha fraterculus (Diptera: Tephritidae) in Native and Exotic Host Plants in Misiones, Northeastern Argentina

    Get PDF
    Some Major host species used by the tephritid fruit flies Anastrepha fraterculus (Wiede-mann) and Ceratitis capitata (Wiedemann), including Acca sellowiana (O. Berg) Burret, Campomanesia xanthocarpa O. Berg, Psidium guajava L., Prunus persica (L.) Batsch, Eriobotrya japonica (Thunb.) Lindl., Citrus reticulata Blanco var. Murcott, C. aurantium L., C. paradisi Macfadyen var. Dalan Dan, and C. paradisi var. Sudashi, were sampled for fruit fly larvae between Feb and Dec 2000 in the northernmost section of the Paranaense forest, in the Province of Misiones, NE Argentina. Both A. fraterculus and C. capitata were obtained from these host plant species, with A. fraterculus accounting for 93% of all tephritid puparia identified. Ten species of larval-pupal parasitoids were recovered from A. fraterculus; Doryctobracon areolatus (Szépligeti), D. brasiliensis (Szépligeti), Utetes anastrephae (Viereck), Opius bellus (Gahan), Diachasmimorpha longicaudata (Ashmead) (Opiinae, raconidae), Odontosema anastrephae Borgmeier, Lopheucoila anastrephae (Rohwer), Aganaspis pelleranoi (Brèthes) (Eucoilinae, Figitidae), Asobara anastrephae (Muessebeck) (Alyssinae, Braconidae), and Aceratoneuromyia indica (Silvestri) (Tetrastichinae, Eulophidae). All these parasitoids, with the exception of D. longicaudata and A. indica, are native to the Neotropical region. No parasitoids were recovered from C. capitata puparia. Asobara anastrephae and O. anastrephae are newly recorded in Argentina, whereas D. brasiliensis, U. anastrephae, and L. anastrephae are newly reported in Misiones. The eucoiline A. pelleranoi wasthe most abundant parasitoid species. Acca sellowiana and P. guajava harbored the highest parasitoid abundance and diversity.Fil: Schliserman, Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones y Transferencia de Catamarca. Universidad Nacional de Catamarca. Centro de Investigaciones y Transferencia de Catamarca; ArgentinaFil: Ovruski Alderete, Sergio Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; ArgentinaFil: Decoll, Olga. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Misiones; ArgentinaFil: Wharton, Robert. Texas A&M University; Estados Unido

    An improved model of the vacuum probe

    Get PDF
    Vacuum probe microbiological device for sampling large areas lightly loaded with microorganism

    A High Throughput Substrate Binding Assay Reveals Hexachlorophene as an Inhibitor of the ER-resident HSP70 Chaperone GRP78

    Get PDF
    Glucose-regulated protein 78 (GRP78) is the ER resident 70 kDa heat shock protein 70 (HSP70) and has been hypothesized to be a therapeutic target for various forms of cancer due to its role in mitigating proteotoxic stress in the ER, its elevated expression in some cancers, and the correlation between high levels for GRP78 and a poor prognosis. Herein we report the development and use of a high throughput fluorescence polarization-based peptide binding assay as an initial step toward the discovery and development of GRP78 inhibitors. This assay was used in a pilot screen to discover the anti-infective agent, hexachlorophene, as an inhibitor of GRP78. Through biochemical characterization we show that hexachlorophene is a competitive inhibitor of the GRP78-peptide interaction. Biological investigations showed that this molecule induces the unfolded protein response, induces autophagy, and leads to apoptosis in a colon carcinoma cell model, which is known to be sensitive to GRP78 inhibition

    Exceptional sperm cooperation in the wood mouse

    Get PDF
    Spermatozoa from a single male will compete for fertilization of ova with spermatozoa from another male when present in the female reproductive tract at the same time. Close genetic relatedness predisposes individuals towards altruism, and as haploid germ cells of an ejaculate will have genotypic similarity of 50%, it is predicted that spermatozoa may display cooperation and altruism to gain an advantage when inter-male sperm competition is intense. We report here the probable altruistic behaviour of spermatozoa in an eutherian mammal. Spermatozoa of the common wood mouse, Apodemus sylvaticus, displayed a unique morphological transformation resulting in cooperation in distinctive aggregations or 'trains' of hundreds or thousands of cells, which significantly increased sperm progressive motility. Eventual dispersal of sperm trains was associated with most of the spermatozoa undergoing a premature acrosome reaction. Cells undergoing an acrosome reaction in aggregations remote from the egg are altruistic in that they help sperm transport to the egg but compromise their own fertilizing ability

    By hook or by crook? Morphometry, competition and cooperation in rodent sperm

    Get PDF
    Background Sperm design varies enormously across species and sperm competition is thought to be a major factor influencing this variation. However, the functional significance of many sperm traits is still poorly understood. The sperm of most murid rodents are characterised by an apical hook of the sperm head that varies markedly in extent across species. In the European woodmouse Apodemus sylvaticus (Muridae), the highly reflected apical hook of sperm is used to form sperm groups, or “trains,” which exhibited increased swimming velocity and thrusting force compared to individual sperm. Methodology/Principal Findings Here we use a comparative study of murine rodent sperm and demonstrate that the apical hook and sperm cooperation are likely to be general adaptations to sperm competition in rodents. We found that species with relatively larger testes, and therefore more intense sperm competition, have a longer, more reflected apical sperm hook. In addition, we show that sperm groups also occur in rodents other than the European woodmouse. Conclusions Our results suggest that in rodents sperm cooperation is more widespread than assumed so far and highlight the importance of diploid versus haploid selection in the evolution of sperm design and function

    Impact of Saccharomyces cerevisiae Fermentation Product on Feed Intake Parameters, Lactation Performance, and Metabolism of Transition Dairy Cattle

    Get PDF
    A Saccharomyces cerevisiae fermentation product (NutriTek; Diamond V, Cedar Rapids, IA) was fed from 29 ± 5 days before calving and through 42 days in milk (DIM) to evaluate the effects on feed intake parameters, milk production, and metabolism. Treatments were control (n = 30) or 18 g/d NutriTek (NT, n = 34) provided as total mixed rations. Cows were individually fed 3×/day prepartum and 2×/day postpartum. Cows were milked 2×/day with samples taken 2×/week for composition analysis. Body weight (BW) was measured at enrollment (day -29 ± 5), day 0, and day 42 relative to calving, and body condition was scored weekly. Blood samples were collected during weeks -4, -2, 1, 2, and 5 relative to calving for biomarkers of metabolism and inflammation. To evaluate adaptive immunity, cows were challenged with a subcutaneous injection of ovalbumin (egg protein) and immune response was determined by serum concentrations of anti-ovalbumin immunoglobulin G (IgG) on days 7, 21, 28, and 35 of lactation. Overall dry matter intake, BW, body condition score, and milk yield were not different between treatments. NutriTek did alter feeding behavior by increasing the number of meals consumed with less time between those meals. Milk fat concentration increased with NT during weeks 4 and 5 of lactation, which contributed to an increase in fat yield during those weeks. There were tendencies for greater milk lactose yield in control cows and greater milk urea nitrogen concentration in NT, but no treatment differences for milk protein concentration or somatic cell count. Assuming equal digestibility, energy balance was more negative for NT during weeks 4 and 5, mirroring the increase in milk fat during that time. Energy density of diets calculated from observed ECM yield and BW change did not differ by treatment. Plasma concentrations of free fatty acids, β-hydroxybutyrate (BHB), glucose, insulin, and the inflammation marker haptoglobin did not differ between treatments. NutriTek increased the incidence of subclinical ketosis (12 vs. 38%, diagnosed by urine ketones). There was no overall treatment effect for immune response to vaccination; however, a treatment × parity interaction indicated greater antibody concentration in primiparous cows supplemented with NT. A partial budget analysis accounting for milk income, feed cost, and expense associated with ketosis treatment indicated an additional $0.35 daily profit per cow for NT vs. control. In conclusion, NT supplementation during the transition period altered feeding behavior and milk fat concentration and ultimately appeared profitable in this scenario, despite the increased incidence of subclinical ketosis and a lack of response in early lactation milk yield

    Diversidade de Parasitóides (Hymenoptera: Braconidae e Figitidae) de larvas frugívoras (Diptera: Tephritidae e Lonchaeidae) na Reserva Florestal Adolpho Ducke, Amazônia Ocidental, Manaus, Brasil

    Get PDF
    This study aimed to identify parasitoid species of frugivorous larvae and to describe the tritrophic interactions involving wild fruits, frugivorous insects and their natural enemies at Adolpho Ducke Forest Reserve (RFAD) (Manaus, AM, Brazil). Collections were performed in four 1 km2 quadrants in the corners of the RFAD. The wild fruits were collected inside the forest in access trails leading to each collection area and in trails that surrounded the quadrants, up to five metres from the trail on each side. The fruits were placed in plastic containers covered with thin fabric, with a vermiculite layer on the base to allow the emergence of flies or parasitoids. Seven Braconidae species were collected, distributed among Opiinae: Doryctobracon areolatus (Szépligeti, 1911), Utetes anastrephae (Viereck, 1913), and Opius sp., and Alysiinae: Asobara anastrephae (Muesebeck, 1958), Phaenocarpa pericarpa Wharton and Carrejo, 1999, Idiasta delicata Papp, 1969, and Asobara sp. Parasitism rates by braconids and figitids are presented. Doryctobracon areolatus was the most frequent, parasitizing the highest number of fly species, and showing the highest parasitism percentage in larvae feeding on Micropholis williamii fruits. The collected figitids belong to Aganaspis nordlanderi Wharton, 1998 and A. pelleranoi (Brethes, 1924). All 15 tritrophic associations are new records for the Brazilian Amazon region. The RFAD is an important natural reservoir of frugivorous larvae parasitoids

    Sperm design and variation in the New World blackbirds (Icteridae)

    Get PDF
    Post-copulatory sexual selection (PCSS) is thought to be one of the evolutionary forces responsible for the rapid and divergent evolution of sperm design. However, whereas in some taxa particular sperm traits are positively associated with PCSS, in other taxa, these relationships are negative, and the causes of these different patterns across taxa are poorly understood. In a comparative study using New World blackbirds (Icteridae), we tested whether sperm design was influenced by the level of PCSS and found significant positive associations with the level of PCSS for all sperm components but head length. Additionally, whereas the absolute length of sperm components increased, their variation declined with the intensity of PCSS, indicating stabilizing selection around an optimal sperm design. Given the diversity of, and strong selection on, sperm design, it seems likely that sperm phenotype may influence sperm velocity within species. However, in contrast to other recent studies of passerine birds, but consistent with several other studies, we found no significant link between sperm design and velocity, using four different species that vary both in sperm design and PCSS. Potential reasons for this discrepancy between studies are discussed

    Large Numbers of Matings Give Female Field Crickets a Direct Benefit but not a Genetic Benefit

    Get PDF
    Female crickets can potentially gain both direct and indirect benefits from mating multiple times with different males. Most studies have only examined the effects of small numbers of matings, although female crickets are capable of mating many times. The goal of this paper is to examine the direct and indirect benefits of mating large numbers of times for female reproductive success. In a previous experiment, female Gryllus vocalis were found to gain diminishing direct benefits from mating large numbers of times. In this study I attempt to determine whether mating large numbers of times yields similar diminishing returns on female indirect benefits. Virgin female Gryllus vocalis crickets were assigned to mate five, ten or 15 times with either the same or different males. Females that mated more times gained direct benefits in terms of laying more eggs and more fertilized eggs. Females that mated with different males rather than mating repeatedly with the same male did not have higher offspring hatching success, a result that is contrary to other published results comparing female reproductive success with repeated versus different partners. These results suggest that females that mate large numbers of times fail to gain additional genetic benefits from doing so
    corecore