76 research outputs found

    Effectiveness of entomopathogenic nematodes in the control of Cydia pomonella larvae in Northern Italy

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    Since 2006, a large scale research on the effectiveness of entomopathogenic nematodes (EPN) in the control of codling moth (CM), Cydia pomonella, overwintering larvae has been performed on about 35 ha of pear orchards per year in Emilia-Romagna, Northern Italy. Steinernema carpocapsae and Steinernema feltiae activity was checked after spray applications of EPNs to the trunk and branches. In 2006, the treatment was applied either in spring or in autumn at different doses, before CM pupation; in 2007 the EPN treatment was applied only in autumn at 1.5 x 109 I.J. ha –1. Every year it was distributed by means of a conventional mist blower. The larval mortality was assessed directly on sentinel larvae in card boards on the trunks and indirectly on the eggs laid by the females of the first CM generation in spring. Moreover, each year, a trial was performed applying only S. carpocapsae on sentinel larvae with the aim of testing this nematode at suitable temperatures but at different water volumes. The CM sentinel larvae were effectively parasitized after autumnal EPN application. Moreover, the egg assessment demonstrated a good decrease in CM population in spring 2007, when EPNs had been applied at the best weather conditions (t° 12-14 °C and rain) in the previous autumn

    Understanding leisure-related program effects by using process data in the HealthWise South Africa Project

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    As the push for evidence-based programming gathers momentum, many human services programs and interventions are under increased scrutiny to justify their effectiveness across different conditions and populations. Government agencies and the public want to be assured that their resources are being put to good use on programs that are effective and efficient. Thus, programs are increasingly based on theory and evaluated through randomized control trials using longitudinal data. Despite this progress, hypothesized outcomes are often not detected and/or their effect sizes are small. Moreover, findings may go against intuition or “gut feelings” on the part of project staff. Given the need to understand how program implementation issues relate to outcomes, this study focuses on whether process measures that focus on program implementation and fidelity can shed light on associated outcomes. In particular, we linked the process evaluation of the HealthWise motivation lesson with outcomes across four waves of data collection. We hypothesized that HealthWise would increase learners’ intrinsic and identified forms of motivation, and decrease amotivation and extrinsic motivation. We did not hypothesize a direction of effects on introjected motivation due to its conceptual ambiguity. Data came from youth in four intervention schools (n = 902, 41.1%) and five control schools (n = 1291, 58.9%) who were participating in a multi-cohort, longitudinal study. The schools were in a township near Cape Town, South Africa. For each cohort, baseline data are collected on learners as they begin grade 8. We currently have four waves of data collected on the first cohort, which is the focus of this paper. The mean age of the sample at wave 3 was 15.0 years (SD = .86) and 51% of students were female. Results suggested that there was evidence of an overall program effect of the curriculum on amotivation regardless of fidelity of implementation. Compared to the control schools, all treatment school learners reported lower levels of amotivation in wave 4 compared to wave 3, as hypothesized. Using process evaluation data to monitor implementation fi147 delity, however, we also conclude that the school with better trained teachers who also reported higher levels of program fidelity had better outcomes than the other schools. We discuss the implications of linking process data with outcome data and the associated methodological challenges in linking these data.Web of Scienc

    Predicting substance use behavior among South African adolescents: The role of leisure experiences across time

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    Using seven waves of data, collected twice a year from the 8th through the 11th grades in a low-resource community in Cape Town, South Africa, we aimed to describe the developmental trends in three specific leisure experiences (leisure boredom, new leisure interests, and healthy leisure) and substance use (cigarettes, alcohol, and marijuana) behaviors and to investigate the ways in which changes in leisure experiences predict changes in substance use behaviors over time. Results indicated that adolescents’ substance use increased significantly across adolescence, but that leisure experiences remained fairly stable over time. We also found that adolescent leisure experiences predicted baseline substance use and that changes in leisure experiences predicted changes in substance use behaviors over time, with leisure boredom emerging as the most consistent and strongest predictor of alcohol, cigarette, and marijuana use. Implications for interventions that target time use and leisure experiences are discussed.Web of Scienc

    Investigations on the efficacy of different products for the control of Stephanitis pyri in an organic pear orchard during the two-year period 2004-'05

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    The results of two trials, carried out respectively in 2004 and 2005, against Stephanitis pyri in an organic pear orchard are reported. Different formulations of the following active substances were tested: pyrethrum + PPBO, rotenone, rotenone + pyrethrum + PPBO, azadirachtin, Beauveria bassiana strain ATCC 74040, Marsiglia and potassium soap; and quassia wood. The pyrethrum + PPBO- and rotenone-based formulated products showed good efficacy, when applied against neonate larvae. A good efficacy was also observed with the azadirachtin-based formulation, but the product may have phytotoxic effects on pear, and therefore its use is not recommended. The B. bassiana-based product showed partial efficacy in controlling the target pest, while the efficacy of the formulations based on Marsiglia soap, Potassium soap and Quassia wood was not satisfactory

    Efficacy of Cydia Pomonella granulosis virus (cpgv) in controlling codling moth in the Emilia-Romagna region

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    During the period 1999 to 2007, numerous field trials were carried out in the Emilia Romagna region in order to test the efficacy of Cydia pomonella Granulosis Virus-based (CpGV) products in controlling codling moth, Cydia pomonella (L.). The trial results demonstrate that CpGV-based products can be considered among the best larvicides currently available on the market. Good results were achieved against I generation larvae, while applications against successive generations did not always provide satisfactory control
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