A BIOECONOMIC SIMULATION APPROACH TO MULTI-SPECIES INSECT MANAGEMENT

Classical approaches to the economics of pest management have focused almost exclusively on single-species models. This study develops and implements a methodology with which to evaluate multi-species, non-stochastic, managerial decisions subject to stochastic elements of the plant-insect system. Multi-species insect management strategies (combinations of scouting interval, threshold value, and choice of pesticide) are analyzed using a physiological mechanistic soybean plant growth model coupled to three insect population dynamics models. Preliminary results indicate that net returns are maximized and variance is reduced with lower thresholds and more frequent scouting than current recommendations

Comparison of monoamine concentrations in the brains of adult male and female Japanese quail.

A fluorometric assay measuring brain tissue concentrations of norepinephrine, dopamine, and serotonin has been validated for Japanese quail. Accuracy, precision, specificity, and parallelism were determined. The sensitivity of the assays was 6 ng/tube, which allowed individual assay of 1 to 2 mg hypothalamic tissue. In Experiment 1, relatively large areas of brain from adult, reproductively active males and females were found to differ significantly in norepinephrine content in optic lobes and for dopamine in right telencephalon. A microdissection technique was used in Experiment 2 to sample small portions of hypothalamic tissue. Sex differences were observed for norepinephrine in the sections containing the lobus paraolfactorius and the preoptic, anterior, and medial hypothalamus. Differences in monoamine content were most apparent when smaller areas dissected by microdissection were analyzed. These results give evidence for sex differences in the monoamine content in specific areas of the brain

Aspectos biológicos de adultos de um parasitóide do bicudo do algodoeiro Biological aspects of a parasitoid of the cotton boll weevil

Bracon sp. é um importante agente de controle biológico de Anthonomus grandis (Boheman). Estudaram-se em laboratório, aspectos biológicos de Bracon sp., utilizando-se como hospedeiro larva do bicudo do algodoeiro, a temperatura de 26 ± 2oC, 70 ± 5% UR e fotofase de 12 horas. O ciclo biológico de Bracon sp. teve duração média de 11,7 dias, o período de incubação de 1 dia, o período médio larval de 3,9 dias, com 4 estádios; a viabilidade larval de 98,7%, o período pré-pupal de 0,6 dia, o período pupal de 6,2 dias, o tempo de pré-oviposição de 4,0 dias. A fêmea colocou, em média, 74 ovos em um período de 27,2 dias, a oviposição média diária de 2,7 ovos/fêmea/dia, o período de pós-oviposição de 3,7 dias e a longevidade de Bracon sp. foi de 34 dias para as fêmeas. A informação da biologia deste braconídeo é necessária para desenvolver estratégias de propagação e colonização do parasitóide.<br>Bracon sp. is an important biological control agent of Anthonomus grandis, the cotton Boll weevil. The objective of this work was to evaluate biological aspects of Bracon sp. using cotton Boll weevil larvae as host, at conditions of 26 ± 2oC, with 70 ± 5% RH and 12h photoperiod. The complete life cycle of Bracon sp. was 11.7 days. The incubation period lasted 1.0 day and the larval period 3.9 days with four stages; the viability of the larvae was 98.7%; prepupal period lasted 0.6 day; and the pupal period lasted 6.2 days. Preoviposition period was 4.0 days, and the females laid an average of 74.0 eggs with in an oviposition period of 27.2 days, while the average daily oviposition rate was 2.7 eggs per female per day, posovipositional lasted 3.7 days, and the longevity of Bracon sp. was 34.0 days in females. The information of the biology of this Braconid is needed to develop parasitoid propagation and colonization strategies