Knowledge about interactions among biological control agents, used in sequence or simultaneously, may help to increase their efficiency, or in the case of conservation biological control, to avoid the impairment of efficiency. The aim of this study was to evaluate the interaction between two isolates of Beauveria bassiana (Bals.) Vuill. (Hypocreales) (Unioeste 47 and Unioeste 57) and Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae), varying the timing of sprays of the fungus. Isolates were sprayed at 109 conidia ml−1 upon cards (1 × 5 cm; i.e., 2 × 105 conidia mm−2) with eggs of Anagasta kuehniella Zeller (Lepidoptera: Pyralidae) and the control group was sprayed with sterile distilled water with Tween® 80 (0.01%). First, the percentage of parasitized eggs was assessed in a choice test: females of T. pretiosum were confined with two cards, one of them treated with either of the fungus isolates, the other a water‐treated control. Second, parasitism was compared on cards sprayed at various time intervals pre‐ vs. post‐parasitism: the number of parasitized eggs was assessed, as well as the parasitoid's emergence percentage, egg‐adult period, offspring sex ratio, and the longevity of parasitizing females. Trichogramma pretiosum preferred to parasitize control eggs (65 and 72%) and parasitization of the treated eggs did not differ between fungus isolates: 35% (Unioeste 47) vs. 28% (Unioeste 57). Spraying before or after parasitizing did not affect the number of parasitized eggs, nor offspring sex ratio; however, both treatments affected the percentage of emerged adults, egg‐adult period, and longevity. These findings suggested that isolates did not interfere in the longevity of parasitizing females. When the fungus was sprayed on the various development stages of the parasitoid within the host egg, or when it was offered to the parasitoid at different times after spraying, differences in adults' longevity, parasitism, emergency period from egg to adult, and sex ratio were observed. Beauveria bassiana may be used in conjunction with this parasitoid in a program of pest control.

The purpose was to evaluate the side effects of strains Metarhizium anisopliae (Metsch.) Sorokin sensu lato Unioeste 43 and M. anisopliae sensu stricto ESALQ 1641 on Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) under controlled conditions. A free-choice test for parasitism was performed, with the confinement of T. pretiosum females mated with cards (1 × 5 cm) containing age-standardized Anagasta kuehniella Zeller eggs, either sprayed with a fungal strain (109 conidia/ml) or 0.01% v/v Tween 80 (control). For the no-choice tests, T. pretiosum females mated were confined with cards sprayed with fungal strains before or after parasitism, and cards with fungal applications at different times. The number of parasitized eggs, percentage of emergence, longevity, egg-to-adult period, sex ratio, total and confirmed mortality by the fungus, and longevity of females that parasitized previously sprayed eggs, were assessed. Histological analysis of immature phases was also performed. The fungus was repellent to T. pretiosum in the free-choice test, while in the no-choice test, fungal applications before and after parasitism did not affect the number of eggs parasitized by T. pretiosum or the sex ratio of emerging adults. However, both strains affected adult emergence rates, the egg-to-adult period, and longevity. Overall, both M. anisopliae strains had minor effects on these biological parameters of T. pretiosum under controlled conditions. Hyphae were not detected in histological observations of immature stages of the parasitoid.

No abstract

The lesser mealworm beetle, Alphitobius diaperinus (Panzer) (Coleoptera: Tenebrionidae), is an important insect pest. The insect acts as a disease vector and reservoir, negatively affecting the health of birds and humans, and harming poultry husbandry. Controlling the lesser mealworm is generally based on using synthetic chemical insecticides, which are sometimes ineffective, and is limited due to market concerns regarding the toxicity of chemical residues in food products. In this context, the present study aimed to evaluate the potential for the combination of physical and chemical methods to control A. diaperinus. Bioassays were conducted using poultry bedding and known populations of beetle adults and larvae. The treatments consisted of the isolated application of 400 g/m2 hydrated lime; 20% added moisture (distilled water); temperature increase to 45°C; an insecticide composed of cypermethrin, chlorpyrifos, and citronellal; and a combination of these factors. Beetle mortality was measured at 7 and 10 d of treatment. The hydrated lime and moisture treatments alone did not control A. diaperinus. Raising the temperature of the poultry bedding to 45°C effectively controlled both larvae (90±6%) and adults (90±4%). The use of insecticide provided adequate control of A. diaperinus in the conditions of the bioassay (93±2% and 68±5% for adults and larvae, respectively). The combination of the studied factors led to the total control of larvae and adults after 7 d of treatment.

RESUMOA busca por informações para o controle de Thaumastocoris peregrinus (Hemiptera: Thaumastocoridae) em Eucalyptus concentra-se no uso de técnicas de controle biológico, entre elas, o uso de fungos entomopatogênicos. Assim, o objetivo deste trabalho, foi avaliar a patogenicidade de isolados de Beauveria bassiana e Isaria sp. sobre Thaumastocoris peregrinus em condições de laboratório. Para isto, foram testados quatro isolados de Beauveria bassiana e um isolado de Isaria sp. na concentração de 1,0 × 10 8 conídios.mL -1 . A solução foi aplicada sobre folhas de Eucalyptus camaldulensis, fornecidas como substrato de alimentação aos insetos, e mantidas em frascos de vidro vedados com filme plástico em câmara climatizada (26 ± 2°C, 14 h de fotofase e U.R. de 70 ± 10%). Foram realizadas quatro repetições (frascos) por isolado com 13 insetos adultos por frasco. As avaliações foram realizadas até o quinto dia após a aplicação. Os insetos mortos foram colocados em câmara úmida para a confirmação da morte pelo patógeno. Todos os isolados foram patogênicos a Thaumastocoris peregrinus. A mortalidade confirmada variou entre 37% e 80,1% para Beauveria bassiana, e foi de 87% para Isaria sp. após 10 dias da aplicação. O maior percentual médio de mortalidade diária (39,9%) ocorreu no quarto dia após o contato do inseto com o substrato pulverizado. Os isolados de Beauveria bassiana e de Isaria sp. avaliados apresentam potencial para o controle de Thaumastocoris peregrinus em laboratório. Palavras-chave: percevejo-bronzeado; fungos entomopatogênicos; controle biológico; eucalipto. ABSTRACTThe search for information to control Thaumastocoris peregrinus (Hemiptera: Thaumastocoridae) in Eucalyptus, focus on the use of biological control techniques, including the use of entomopathogenic fungi. The objective of this study was evaluated the pathogenicity of Beauveria bassiana and Isaria sp. Ciência Florestal, Santa Maria, v. 28, n. 1, p. 403-411, jan.-mar., 2018 ISSN 1980 Lorencetti, G. A. T. et al. 404 maintained in glass bottles sealed with plastic film in a climatic chamber (26 ± 2 ° C, 14 h photoperiod and U.R. 70 ± 10%). Four replicates were performed (bottles) for isolated with 13 adult insects per bottle. Each bottle received 13 adult insects. Evaluations were performed until the fifth day after application. The dead insects were placed in humid chamber for confirmation of death by pathogen. All isolates were pathogenic to Thaumastocoris peregrinus. The confirmed mortality ranged between 37% and 80.1% for Beauveria bassiana, and was 87% for Isaria sp. after 10 days of application. The highest mean percentage of daily mortality (39.9%) occurred on the fourth day after contact with the substrate insect spray. The isolates of Beauveria bassiana and Isaria sp. evaluated presented potential to control Thaumastocoris peregrinus under laboratory conditions.