A nivel mundial, un tercio de las partes comestibles de los alimentos producidos para el consumo humano se desperdicia, siendo importante la generación de propuestas para el uso sostenible de los mismos. El objetivo de este trabajo fue determinar la influencia de cuatro dietas, a base de salvado de arroz, en tres cantidades y tres densidades larvales sobre la duración del periodo larval, porcentaje de viabilidad larval y peso larval de Chrysomya megacephala. Los Resultados indican que la duración del periodo larval y el porcentaje de viabilidad larval fueron favorecidos con el incremento de salvado de arroz en la dieta. En contraste, el peso larval se redujo con este incremento. En relación con la densidad larval, 5 larvas/g de dieta presentó el mayor porcentaje de viabilidad larval, sin presentar efectos significativos sobre la duración del periodo y peso larval. La duración del periodo larval y el porcentaje de viabilidad larval no difirieron al incrementar la cantidad de dieta, mientras que el peso larval aumentó favorablemente. En relación con la interacción de los factores, la duración del periodo larval disminuyó conforme se incrementó la densidad larval en la dieta con mayor contenido de salvado de arroz, y el peso larval aumentó conforme se incrementó la cantidad de dieta. Finalmente, 5 larvas/g de dieta es la densidad ideal de C. megacephala, el peso larval aumenta con la cantidad de dieta y la duración del periodo larval es inversamente proporcional a la densidad larval en la dieta con mayor contenido de salvado de arroz.

Globally, a third of the edible parts of food produced for human consumption are wasted, therefore it is important the generation of proposals for the sustainable use thereof. The objective of this investigation was to determine the influence of four diets, based in rice bran, in three quantities and three larval densities on the duration of larval period, larval viability and larval weight of C. megacephala. The results indicate that the duration of larval period and percentage of larval viability were favored when the content of rice bran in the diet was increased. In contrast, the larval weight was decreased. In relation with larval density, 5 larvae/g of diet presented the greatest percentage of larval viability, without significant effects on the duration of larval period and larval weight. The duration of larval period and larval viability did not differ by increasing the quantity of diet, while the larval weight increased favorably. In relation with the interaction of factors, the duration of larval period decreased as the larval density increased, in the diet with the greatest content of rice bran, and the larval weight increased as the quantity of diet increased. Finally, the density of 5 larvae/g of diet is the ideal density of C. megacephala, the larval weight increases with the quantity of diet, and the duration of larval period is inversely proportional to the larval density in the diet with the greatest content of rice bran.

Comparative GC/MS analysis of airborne volatiles produced by males and females of the guava weevil Conotrachelus psidii (Coleoptera: Curculionidae: Molytinae) showed the presence of a malespecific electroantennographically active compound identified as (1R,2S,6R)-2-hydroxymethyl-2,6- dimethyl-3-oxabicyclo[4.2.0]octane (papayanol). Release of this compound was dependent on the photoperiod, taking place primarily during the scotophase, with a maximum release between 2 and 6 h after the onset of the scotophase. Y-tube olfactometer bioassays revealed a strong attractiveness of the papayanol to male and female weevils considering the presence of the plant volatiles.

Considerada praga-chave da cultura da goiaba, Conotrachelus psidii Marshall (Coleoptera: Curculionidae) tem causado grandes prejuízos em vários países produtores desta fruta. A pesquisa objetivou avaliar os parâmetros biológicos da praga, sob condições controladas, através do desenvolvimento de uma técnica de criação que permitiu efetuar observações diárias de pré-pupas e pupas. Constatou-se que o substrato adequado para manutenção dessas fases foi o solo argiloso umedecido com viabilidade de 78%, sendo este o tipo de solo utilizado na técnica de criação, que foi desenvolvida para trabalhos em câmara climatizada, à temperatura constante de 25 ± 1º C, fotoperíodo de 12 horas e UR de 70% ± 10%. Quanto aos aspectos biológicos, a duração média do período de ovo, larva, pré-pupa, pupa e ovo-pupa foi de: 4,25; 12,2; 106,6; 14,88 e 138,4 dias, respectivamente. A duração média do período da fase adulta, no solo, início da alimentação, pré-oviposição, longevidade e pós-oviposição foi de, 22; 11; 51,9; 149,32 e 7,18 dias, respectivamente. O período médio de oviposição foi de 120,27 dias, com um número médio de 343,63 ovos por fêmea. A técnica de criação desenvolvida permitiu acompanhar diariamente o desenvolvimento de pré-pupas, pupas e adultos do gorgulho-da-goiaba, sem que eles necessitassem reconstruir nova câmara, mostrando ser menos estressante e onerosa do ponto de vista energético.

The species Conotrachelus psidii Marshall (Coleoptera: Curculionidae), considered a key pest of guava cultivation, is causing major damage in several producing countries of the fruit. The purpose of this study was to evaluate the biological parameters of the pest under controlled conditions, through the development of a rearing technique of pre-pupae and pupae that would allow daily observations. It was found that the substrate for an appropriate development of these phases was moistened clay soil (with survival rate of 78%). This soil type was used in the rearing method, which was developed to work in a climatic chamber at a constant temperature of 25 ± 1ºC, 12 h photoperiod and 70% RH ± 10%. The biological stages of the egg, larva, pre-pupa, pupa and egg-pupa lasted, on average, 4.25, 12.2, 106.6, 14.88, and 138.4 days, respectively. The adult stages in the soil, beginning of feeding, pre-oviposition, longevity, and post-oviposition lasted on average 22, 11, 51.9, 149.32, and 7.18 days, respectively. The average oviposition period lasted 120.27 days, with an average of 343.63 eggs per female. By the proposed rearing method, the development of pre-pupae, pupae and adults of the guava weevil could be daily monitored, without requiring the construction of a new chamber by the insects, thus reducing stress and input in terms of energy.