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1.
Braz J Biol ; 82: e261227, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35976355

RESUMEN

The nutrient stress hypothesis predicts that galling insects prevail on host plants growing in habitats with soils of low nutritional quality. Caryocar brasiliense (Caryocaraceae) is host to four different leaf-galling insects. These insects have the potential to cause a reduction in the production of C. brasiliense fruits, an important source of income for many communities in Brazil. We studied the effects of soil physical and chemical characteristics on the abundance, species richness, and diversity of galling insects and their natural enemies on C. brasiliense trees growing under three different soil conditions. Our data corroborate the hypothesis that in nutritionally poor (e.g., lower phosphorus content) and worse physical textures (e.g., sandy) soils, host plants support higher species richness and diversity of galling insects. However, the abundance of Eurytoma sp. (the most common gall in C. brasiliense), was correlated with a higher phosphorus concentration in the soil (better nutritional condition). The percentage of galled leaflets and the area of leaflets occupied by Eurytoma sp galls were higher in the more fertile soil. In this soil, there was greater abundance, species richness, and diversity of parasitoids of Eurytoma sp. (e.g., Sycophila sp.) and predators (e.g., Zelus armillatus). Our data indicate the importance of habitat quality in the composition of the galling insect community and the impact of soil properties in mediating the distribution of these insects in C. brasiliense.


Asunto(s)
Malpighiales , Árboles , Animales , Biodiversidad , Insectos , Fósforo , Plantas , Suelo
2.
Braz J Biol ; 84: e254628, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35239787

RESUMEN

Insects' ethology is an important factor when it is desired to carry out pest management. This knowledge makes it possible to manipulate behavioral activities, repel, or attract insects according to needs and interests. The maize weevil Sitophilus zeamais (Mots., 1855) (Coleoptera: Curculionidae), one of the main stored grain pests, has been the target of studies of behavioral changes studies through natural substances due to its resistance to different insecticidal classes. Thus, this study aimed to evaluate the effect of sublethal concentrations of neem extract and copaiba oil on the locomotor behavior of S. zeamais. The behavioral characteristic considered were walking activity, the frequency of contact of insects with the treated grain mass, and the time spent for this behavior. The walking activity of the S. zeamais increased with exposure to Neem extract and Copaiba oil. In general, the Neem extract and Copaiba oil-induced more contact with grain mass than the control, suggesting an attractive effect on the insect, however more significant for the Neem oil. The insect's behavior was altered, presenting a specific path due to Copaiba oil and Neem extract stimuli. These results indicate that Copaiba oil and Neem extract can be a potential alternative for controlling S. zeamais on stored products since changes in this pests' behavior can reduce qualitative and quantitative grain damage. Thus, the development of products based on Copaiba oil and Neem extract may be helpful for storage pest management.


Asunto(s)
Control de Insectos , Insecticidas , Aceites Volátiles , Extractos Vegetales , Gorgojos , Animales , Control de la Conducta , Insecticidas/farmacología , Melia/química , Aceites Volátiles/farmacología , Extractos Vegetales/farmacología
3.
Neotrop Entomol ; 47(2): 318-325, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28822099

RESUMEN

Neoleucinodes elegantalis (Guenée) (Lepidoptera: Crambidae) is one of the major pests of solanaceous plants in South America. It is considered a great threat by the European and Mediterranean Plant Protection Organization due to the serious economic damage that it causes on tomato farms; therefore, controlling this pest is a challenging task in South America. Controlling N. elegantalis at the egg stage is the best way to prevent it from damaging crops; however, thorough studies about the effectiveness of chemicals on the different life stages of this insect pest are lacking. In this study, the effects of different chemical classes were evaluated on N. elegantalis adults, female oviposition behavior, larvae, eggs, and embryonic development. None of the tested insecticides demonstrated toxicity to the adults; however, the results showed that cartap hydrochloride affects oviposition behavior. Moreover, methomyl and cartap hydrochloride exhibited high toxicity against the eggs and larvae, with higher than 80% of mortality. These insecticides interrupted larval hatching and caused alterations in the chorion layer. Flubendiamide and deltamethrin demonstrated toxicity on N. elegantalis larvae; however, lufenuron, indoxacarb, methoxyfenozide, and chlorantraniliprole demonstrated low toxicity on both eggs and larvae, with lower than 70% of mortality. Fruit treated with cartap hydrochloride had a deterrent effect. The ovicidal activity revealed by methomyl and cartap hydrochloride might provide new approaches regarding insecticide effects on eggs. Methomyl, cartap hydrochloride, flubendiamide, and deltamethrin demonstrated toxicity on larvae. The evaluation of the chorion of the eggshell in this study has clarified the toxic effect of methomyl and cartap hydrochloride on eggs.


Asunto(s)
Insecticidas , Lepidópteros , Animales , Benzamidas , Femenino , Hidrazinas , Control de Insectos , Hormonas Juveniles , Larva , Metomil , Nitrilos , Oviposición , Óvulo , Oxazinas , Piretrinas , Solanum , Sulfonas , Tiocarbamatos , ortoaminobenzoatos
4.
J Econ Entomol ; 104(6): 1909-17, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22299352

RESUMEN

The currently existing sample procedures available for decision-making regarding the control of the coffee berry borer Hypothenemus hampei (Ferrari) (Coleoptera: Curculionidae: Scolytinae) are time-consuming, expensive, and difficult to perform, compromising their adoption. In addition, the damage functions incorporated in such decision levels only consider the quantitative losses, while dismissing the qualitative losses. Traps containing ethanol, methanol, and benzaldehyde may allow cheap and easy decision-making. Our objective was to determine the economic injury level (EIL) for the adults of the coffee berry borer by using attractant-baited traps. We considered both qualitative and quantitative losses caused by the coffee borer in estimating the EILs. These EILs were determined for conventional and organic coffee under high and average plant yield. When the quantitative losses caused by H. hampei were considered alone, the EILs ranged from 7.9 to 23.7% of bored berries for high and average-yield conventional crops, respectively. For high and average-yield organic coffee the ELs varied from 24.4 to 47.6% of bored berries, respectively. When qualitative and quantitative losses caused by the pest were considered together, the EIL was 4.3% of bored berries for both conventional and organic coffee. The EILs for H. hampei associated to the coffee plants in the flowering, pinhead fruit, and ripening fruit stages were 426, 85, and 28 adults per attractive trap, respectively.


Asunto(s)
Escarabajos/efectos de los fármacos , Productos Agrícolas/economía , Control de Insectos/métodos , Feromonas/farmacología , Animales , Ácido Benzoico/farmacología , Brasil , Café , Etanol/farmacología , Femenino , Control de Insectos/economía , Metanol/farmacología , Densidad de Población , Tamaño de la Muestra , Muestreo , Estaciones del Año
6.
Rev. Assoc. Med. Bras. (1992) ; 43(2): 99-104, abr.-jun. 1997. tab
Artículo en Portugués | LILACS, SES-SP | ID: lil-197140

RESUMEN

A analise de performance psicomotora dde crianças institucionalizadas é de fundamental importância no planejamento de atividades educativas. Estudos anteriores têm mostrado prejuízos desta funçao em crianças de creches. Objetivo. Comparar o desempenho no teste de triagem de Denver em crianças de 2 a 6 anos de idade, de creches conveniadas com a Prefeitura de Sao Paulo, antes e após seis meses de intervençao nutricional com suplemento alimentar enriquecido com ferro. Método. Foram analisadas 130 crianças de 2 a 6 anos de idade, em três creches municipais de Sao Paulo, aplicando-se o teste de Denver, por psicólogas treinadas, comparando-se os resultados de acordo com o sexo, faixa etaria e estado nutricional, antes e após período de suplementaçao alimentar. Resultados. A maior parte das crianças teve desempenho normal, tanto na primeira aplicaçao (70,80 por cento), como na segunda (80,80 por cento), sem modificaçao do estado nutricional. Na comparaçao dos resultados, 76,92 por cento nao modificaram o desempenho e 18,46 por cento melhoraram significativamente. Em relaçao ao sexo, nao foram encontradas diferenças significantes, enquanto que, para a faixa etaria, houve melhora significante entre as crianças de 4 a 6 anos. Conclusoes. Além do aspecto nutricional, fatores como prontidao para aprendizagem, organizaçao familiar e orientaçao psicopedagógica das creches devem estar favorecendo o desenvolvimento, mesmo considerando-se o baixo nível socioeconomico da populaçao estudada.


Asunto(s)
Humanos , Femenino , Preescolar , Niño , Guarderías Infantiles , Desarrollo Infantil , Discapacidades del Desarrollo/diagnóstico , Nutrición del Niño , Pruebas Neuropsicológicas , Alimentos Fortificados , Discapacidades del Desarrollo/dietoterapia , Encuestas Nutricionales , Estadísticas no Paramétricas , Hierro de la Dieta/uso terapéutico , Pruebas Neuropsicológicas
7.
Rev Assoc Med Bras (1992) ; 43(2): 99-104, 1997.
Artículo en Portugués | MEDLINE | ID: mdl-9336043

RESUMEN

UNLABELLED: Psychomotor and development analysis must be emphasized when studying institutionalized children. Many previous investigations have been showing deleterious effects of day care centers over developmental performance in children. OBJECTIVE: This study is aimed at comparing the performance in the Development Screening Test (Denver) in children attending day care centers, before and after nutritional intervention with an energetic supplement enriched with iron. METHOD: 130 children from 2 to 6 years old, attending three municipal day care centers, were evaluated by means of the application of the Denver test; by trained psychologists, comparing the collected data according to sex and age group, before and after six months intervention with iron enriched protein energetic supplement. RESULTS: Most of the children had normal performance, both in first application (70.80%), and in the second one (80.80%). When comparing these results, 76.92% of the children had not altered their performance and 18.46% improved it substantially. As to sex, no significant differences were found and as to age group, there was significant improvement among children aged 4 to 6 years of age. CONCLUSIONS: Besides the nutritional aspects, factors such as learning readiness, family organization, and psychopedagogic orientation to the day care centers, must have fostered development, even if the low socioeconomic level of the studied population is considered.


Asunto(s)
Guarderías Infantiles , Desarrollo Infantil , Fenómenos Fisiológicos Nutricionales Infantiles , Discapacidades del Desarrollo/diagnóstico , Pruebas Neuropsicológicas , Niño , Preescolar , Discapacidades del Desarrollo/dietoterapia , Femenino , Alimentos Fortificados , Humanos , Hierro de la Dieta/uso terapéutico , Masculino , Encuestas Nutricionales
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