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El objetivo del estudio fue determinar la efectividad de captura de bracónidos (Hymenoptera: Braconidae) con platos-trampa de color (amarillo, azul, crema y verde), a dos alturas (0 y 90 cm) durante cuatro semanas en el Área Natural Protegida “Cerro Punhuato” (Morelia, Michoacán, México). La reflectancia de cada color se midió con un espectrofotómetro analítico de campo. Se capturaron 104 especímenes pertenecientes a 14 subfamilias y 28 géneros. Los platos-trampa de color amarillo y verde capturaron la mayor cantidad de especímenes y la mayor diversidad de géneros. La similitud estimada con el índice de Bray-Curtis entre ambos colores fue de 56,5 %. Los platos-trampa amarillos instalados a nivel del suelo superaron significativamente la captura de los platos verdes en una semana. El nivel de reflectancia que tienen los platos-trampa verdes y amarillos es muy similar en los intervalos de 360 a 530 nm, lo que posiblemente indique que éste sea el intervalo de longitud de onda en que los bracónidos son atraídos por estos colores.

The Asian citrus psyllid, Diaphorina citri (Kuwayama) (Hemiptera: Liviidae), is a severe pest of citrus orchards worldwide. Its control is based mainly on the use of conventional insecticides, and resistance to many of those compounds is widespread. Phenotypic bioassays to detect resistance compare the response of a field-collected population with a laboratory-reared population that is susceptible to insecticides. This comparison usually does not involve a susceptible field-collected counterpart since its existence is currently rare. We found an isolated field population of D. citri living on a wild host, orange jasmine (Murraya paniculata [L.] Jack). Considering its lifetime fly capacity, gene flow with any insecticide-treated population was nonexistent or negligible. Thus, we determined the response in fourth-instar nymphs and unsexed 2- to 5-d-old adults in bioassays of commercial formulations of the commonly used insecticides chlorpyrifos, malathion, imidacloprid, and spinosad. In the bioassays, insects were placed on leaf discs previously immersed for 10 s in the respective insecticide concentrations. For adults, the lowest concentration–mortality response was with chlorpyrifos (lethal concentration 50 [LC50] of 0.72 mg L-1 and lethal concentration 95 [LC95] of 1.02 mg L-1). The highest toxicity response was with malathion (LC95 of 0.05 mg L-1). The highest toxicity response with fourth-instar nymphs was observed with spinosad (LC50 of 0.007, LC95 of 0.021 mg L-1). The estimated LC50 and LC95 values for chlorpyrifos, malathion, and spinosad were lower than those documented worldwide for these insecticides in susceptible populations of D. citri.