RESUMO
Knowledge of the persistence of Cry proteins in transgenic corn residue after harvest is necessary to assess the ecological risk to nontarget organisms. The amount of protein remaining in crop residue declines over time by a combination of microbial decomposition and leaching, both influenced by temperature, precipitation, and the amount of residue-soil contact. Here, we investigated how long biologically active Cry proteins persist in SmartStax corn residue expressing Cry1A.105, Cry1F, Cry2Ab2, Cry3Bb1, and Cry34/35Ab1, when subjected to four post-harvest practices (chisel plow tillage, flail mowing, cover crop planting, and undisturbed residue). Protein activity in residue samples collected up to 25 weeks after harvest was measured by Ostrinia nubilalis feeding bioassays and cross validated with detection frequencies determined by ELISA. All corn residue remained above ground in the flail-mowed and undisturbed treatments, while the cover crop and chisel plow treatments left 88.3 and 39.6% of the residue remaining above ground, respectively. Cry proteins retained biological activity for as long as 24 weeks after harvest when residue was left above ground with less soil contact, typical of no-till corn systems. ELISA detections were positively correlated with results of the feeding bioassays, which revealed the presence of active proteins beyond the point of ELISA detection.
Assuntos
Bacillus thuringiensis , Animais , Animais Geneticamente Modificados , Bacillus thuringiensis/genética , Bacillus thuringiensis/metabolismo , Proteínas de Bactérias/genética , Endotoxinas/genética , Endotoxinas/metabolismo , Proteínas Hemolisinas/genética , Plantas Geneticamente Modificadas/metabolismo , Solo , Zea mays/genética , Zea mays/metabolismoRESUMO
Field and laboratory experiments were carried out on the island of Oahu, HI, to compare the susceptibility of the two most commonly grown banana (Musa sp.) cultivars in the state ('Dwarf Brazilian' or Santa Catarina [locally known as dwarf apple] and 'Williams') to the aphid-borne Banana bunchy top virus (genus Babuvirus, family Nanoviridae, BBTV). Several morphological and physiological features of the two cultivars were monitored to determine whether the banana aphid, Pentalonia nigronervosa Coquerel (Hemiptera: Aphididae), transmits BBTV to both cultivars at a similar rate; and whether after successful inoculation, does each cultivar respond similarly to viral infection. Results from the laboratory experiment showed that a similar percentage of both cultivars were infected with BBTV by aphid vectors (> 90% for both cultivars). However, field results showed a significantly lower percentage of dwarf apple (39%) infected with BBTV compared with Williams (79%). We also found that all physiological and morphological features measured (i.e., plant height, leaf area, canopy, chlorophyll level, and moisture content) for both cultivars were impacted similarly by BBTV. The incubation period, or the time between plant infection and initial appearance of disease symptoms, was similar for both cultivars. Results also showed that BBTV transmission efficiency was lower in the field than in the laboratory, despite that more aphids per plant were used for field than laboratory inoculation tests. The results highlight the potential use of less susceptible cultivars to help manage BBTV and the importance of screening banana varieties in the field to determine their response to vectors and associated diseases.
Assuntos
Agricultura/métodos , Afídeos/virologia , Babuvirus/fisiologia , Musa/virologia , Doenças das Plantas/virologia , Análise de Variância , Animais , Havaí , Interações Hospedeiro-Patógeno , Especificidade da Espécie , Fatores de TempoRESUMO
BACKGROUND: Poor mental health in the perinatal period is associated with a number of adverse outcomes for the individual and the wider family. The unique circumstances in which military spouses/partners live may leave them particularly vulnerable to developing perinatal mental health (PMH) problems. METHODS: A scoping review was carried out to review the literature pertaining to PMH in military spouses/partners using the methodology outlined by Arksey and O'Malley (2005). Databases searched included EBSCO, Gale Cengage Academic OneFile, ProQuest and SAGE. RESULTS: Thirteen papers fulfilled the inclusion criteria, all from the USA, which looked a PMH or well-being in military spouses. There was a strong focus on spousal deployment as a risk factor for depressive symptoms and psychological stress during the perinatal period. Other risk factors included a lack of social/emotional support and increased family-related stressors. Interventions for pregnant military spouses included those that help them develop internal coping strategies and external social support. CONCLUSIONS: US literature suggests that military spouses are particularly at risk of PMH problems during deployment of their serving partner and highlights the protective nature of social support during this time. Further consideration needs to be made to apply the findings to UK military spouses/partners due to differences in the structure and nature of the UK and US military and healthcare models. Further UK research is needed, which would provide military and healthcare providers with an understanding of the needs of this population allowing effective planning and strategies to be commissioned and implemented.
Assuntos
Depressão , Militares , Cuidado Pré-Natal , Estresse Psicológico , Feminino , Humanos , Saúde Mental , Gravidez , Fatores de Risco , Cônjuges , Estados UnidosRESUMO
The invasive brown marmorated stink bug, Halyomorpha halys (Stål) (Heteroptera: Penatomidae), is a major pest of agricultural crops in the Mid-Atlantic States. Here we report the seasonal abundance, host preference, and injury potential of H. halys on tomato, bell pepper, green bean, sweet corn, eggplant, and okra in a small-scale, diversified vegetable farm setting. Life-stage densities, feeding injury, and crop phenology were monitored throughout the growing season in each crop. Populations consisted of both overwintered adults and F1 progeny and encompassed almost two generations over the growing season. H. halys preferred host plants with reproductive structures for feeding and was more abundant and capable to reproduce on vegetable crops that had extended periods of fruiting. Sweet corn, okra, and bell pepper had significant higher abundances of adults and nymphs compared with green bean, eggplant, and tomato. Results showed significant differences in the reproductive suitability of the host plants, as evident by the relative proportion of nymphal stages to adults. Eggplant, okra, and bell pepper were the most suitable host plants for reproduction and development, as evident by higher proportions of nymphs, with abundance trends indicating progressive development to adult eclosion. Crop loss potential due to H. halys feeding injury varied significantly among vegetable host plants. Sweet corn, okra, bell pepper, and tomato were very susceptible and experienced the highest injury rate per stink bug. The implications of these findings with respect to sampling and management of H. halys in vegetable production are discussed.
RESUMO
Little is known about the incidence of cancer among farmworker populations or about effective strategies for communicating with farmworkers about cancer prevention. Some studies suggest that farmworkers may have unusually high incidences of skin and cervical cancers. With these two cancers as the focus, a group of interviewers, researchers, and health communication specialists set out to create, implement, and evaluate a cancer control demonstration project geared toward farmworkers. In 1994, a situation analysis was conducted to identify constraints and opportunities for providing farmworkers with cancer control information and services. The situation analysis provided valuable information to aid in developing intervention and evaluation strategies. This paper outlines how and why the situation analysis was conducted and what was learned with regard to the farmworker population on the Delmarva Peninsula. Living conditions and the local availability of cancer control services are described. Obstacles to conducting research and interventions with farmworkers are highlighted. Based on what was learned, recommendations are made for designing cancer control research and intervention for farmworkers.