Abstract The aims of this work were to characterize the damage caused by Paraulaca dives in feijoa (Acca sellowiana) and develop a diagrammatic scale to evaluate the severity of herbivory. The evaluations were carried out in a feijoa progenies orchard with eight-year-old. The beetles caused damage mainly on leaves, from October to December (spring season). The distribution of beetles in the orchard occurred randomly, not following a defined pattern of incidence. The diagrammatic scale of herbivory severity was represented by seven levels (1%, 3%, 5%, 7%, 15%, 32%, and 55% of the leaf area consumed). The use of this diagrammatic scale significantly increased the precision and accuracy of severity estimates by inexperienced evaluators. This can help in strategies to control this pest to expand the cultivation of feijoa in Brazil.

O objetivo deste trabalho foi avaliar a atividade inseticida da terra de diatomácea (TD) em diferentes temperaturas ambiente sobre adultos de Sitophilus zeamais e sua progênie, utilizando-se diferentes doses e períodos de exposição. Os experimentos foram realizados em placas de Petri contendo 40 g de grãos inteiros de milho, tratados com TD nas doses de 0; 0,25; 0,5 e 1,0 kg Mg-1. Cada placa foi infestada com 25 adultos de S. zeamais e mantida em câmaras climáticas nas temperaturas de 20, 25, 30, 35 e 40 ºC. A mortalidade dos insetos foi contabilizada após seis e 15 dias do início dos bioensaios. Os grãos avaliados aos 15 dias foram separados dos insetos e mantidos nas placas por mais 75 dias sob as mesmas condições de temperatura. Após este período avaliou-se o efeito da temperatura ambiente e das doses da TD sobre a emergência de S. zeamais na geração F1. Verificou-se que a mortalidade de S. zeamais aumentou com o incremento da dose e da temperatura nos períodos de exposição de seis e 15 dias; já o número de insetos emergidos reduziu com o aumento da temperatura nesses dois períodos de exposição. O aumento da temperatura e do período de exposição favoreceu a eficácia da TD em menores doses, para controle de S. zeamais.

The objective of this study was to evaluate the insecticidal activity of diatomaceous earth (DE) at different ambient temperatures on adult Sitophilus zeamais and progeny, using different doses and exposure periods. The experiments were performed in Petri dishes containing 40 g of the whole corn kernel, treated with DE at doses of 0, 0.25, 0.5 and 1.0 kg Mg-1. Each dish was infested with 25 S. zeamais adults and kept at climatic chambers under temperatures of 20, 25, 30, 35 and 40 ºC. The insect mortality was recorded after six and 15 days from the beginning of the bioassays. The grains evaluated at 15 days were separated from insects and kept in the dishes for another 75 days under the same temperature conditions. After this period the effect of ambient temperature and of diatomaceous earth doses on the emergence of S. zeamais in the F1 generation was evaluated. It was found that the mortality of S. zeamais increased with the higher dose and temperature during the exposure period of six and 15 days. The number of insects emerged reduced with increasing temperature in these two exposure periods. The increase of temperature and exposure period favored the efficacy of DE in lower doses for control of S. zeamais.

O conhecimento da ovigenia em parasitóides é importante para estudos básicos em fisiologia e para o controle biológico aplicado. O padrão de ovigenia e OVIGENY OF Palmistichus elaeisis (HYMENOPTERA: EULOPHIDAE) o tipo de ovaríolo do parasitóide Palmistichus elaeisis Delvare & LaSalle (Hymenopera: Eulophidae) foram estudados em fêmeas recém-emergidas e em intervalos de sete, 14, 24 de 48 horas após a emergência em pupas de Tenebrio molitor L. (Coleoptera: Tenebrionidae). Fêmeas de P. elaesis apresentaram o ovário composto por quatro ovaríolos do tipo meroístico politrófico. A deposição de vitelo e corionogênese em P. elaeisis foram concluídas 24 horas após a emergência. Fêmeas com 48 horas de idade apresentam grande quantidade de ovos prontos para a oviposição. Esses resultados podem ajudar a melhoria da produção massal de P. elaeisis e o controle biológico aplicado com esse parasitóide.

The knowledge on ovigeny in parasitoids is important for basic studies on physiology and applied biological control. The ovigeny pattern and type of ovariole of the parasitoid Palmistichus elaeisis Delvare & LaSalle (Hymenoptera: Eulophidae) were studied in newly-emerged females at seven, 14, 24 and 48 h intervals after their emergence from Tenebrio molitor L. pupae (Coleoptera: Tenebrionidae). Females of P. elaeisis presented ovaries composed by four ovarioles of the meroistic polytrophic type. The yolk accumulation and chorionogenesis in P. elaeisis were concluded 24 h after the female emergence. The 48 h-old females show a high quantity of egg ready for oviposition. These findings can help to improve the mass production of P. elaeisis and the augmentative biological control by using this natural enemy.

Trichogramma spp. (Hymenoptera: Trichogrammatidae) can control Diaphania hyalinata Linnaeus (Lepidoptera: Pyralidae). On the other hand, pesticides may reduce the efficiency of natural enemies. The objective was to evaluate the side-effects of fungicides used in the production of cucurbitaceous crops on Trichogramma atopovirilia Oatman & Platner parasitizing D. hyalinata eggs. The fungicides used in bioassays were: azoxystrobin (0.08 g active ingredient [ai] L-1), chlorothalonil (2.00 g ai L-1), mancozeb (1.60 g ai L-1), tebuconazole (0.25 g ai L-1) and thiophanate-methyl (0.49 g ai L-1). Cardboards with 30 D. hyalinata eggs previously immersedin fungicide solutions and distilled water (control) were offered separately to 20 newly emerged T. atopovirilia females in glass tubes. Parasitism, parasitism reduction, emergence, sex ratio, and number of individuals per egg were evaluated. The fungicides chlorothalonil, thiophanate-methyl and tebuconazole reduced parasitism of T. atopovirilia by 43.37, 27.64 and 18.51%, respectively. However, parasitism with azoxystrobin (79.21%) was higher than the control (67.37%) (P ≤ 0.05). Chlorothalonil, thiophanate-methyl and tebuconazole reduced emergence by 73.77, 75.62 and 79.35% (P ≤ 0.05), respectively. Azoxystrobin and thiophanate-methyl reduced the sex ratio by 0.77 and 0.76 (P ≤ 0.05), respectively. Fungicides did not reduce the number of individuals per egg. The fungicides azoxystrobin and mancozeb were selective for T. atopovirilia for most studied parameters suggesting that these products must have the priority in crop disease management to allow efficient biological control of T. atopovirilia against D. hyalinata.

Trichogramma spp. (Hymenoptera: Trichogrammatidae) pueden controlar Diaphania hyalinata Linnaeus (Lepidoptera: Pyralidae). Sin embargo, los plaguicidas pueden reducir la eficiencia de los enemigos naturales. El objetivo de este trabajo fue evaluar la influencia de los fungicidas utilizados en la producción de cucurbitáceas en Trichogramma atopovirilia Oatman & Platner sobre huevos de D. hyalinata. Se evaluaron los fungicidas azoxystrobina (0.08 g ingrediente activo [ia] L-1), clorotalonil (2.00 g ia L-1), mancozeb (1.60 g ia L-1), tebuconazole (0.25 g ia L-1) and tiofanato-metil (0.49 g ia L-1). Tarjetas con 30 huevos de D. hyalinata previamente sumergidos en los fungicidas y en agua destilada (control) fueron ofrecidas a 20 hembras de T. atopovirilia con hasta 24 h de emergencia individualizadas en tubos de vidrio. Se evaluó parasitismo, reducción de parasitismo, emergencia, proporción sexual en la población y el número de individuos emergidos por huevo. Los fungicidas clorotalonil, tiofanato-metil y tebuconazol redujeron el parasitismo de T. atopovirilia en 43,37; 27,64 y 18,51%, respectivamente. Sin embargo, el parasitismo con azoxistrobina (79,21%) fue mayor que el control (67,37%) (P ≤ 0,05). Clorotalonil, tiofanato-metilo y el tebuconazol redujo la aparición de 73,77, 75,62 y 79,35% (P ≤ 0,05), respectivamente. Azoxistrobina y tiofanato-metil reduciran la proporción de sexos de 0,77 y 0,76 (P ≤ 0,05), respectivamente. Ninguno de los fungicidas redujo el número de individuos por cada huevo. Los fungicidas azoxistrobina y mancozeb fueron selectivos para T. atopovirilia en la mayoría de los parámetros estudiados, por lo tanto, deberían tener prioridad en el manejo de enfermedades de cucurbitáceas para permitir el uso eficiente de los enemigos naturales de D. hyalinata.

Mass rearing of parasitoids depends on choosing appropriate alternative hosts. The objective of this study was to select alternative hosts to rear the parasitoid Palmistichus elaeisis Delvare & LaSalle, 1993 (Hymenoptera: Eulophidae). Pupae of the lepidopterans Anticarsia gemmatalis Hübner, 1818 (Lepidoptera: Noctuidae), Bombyx mori Linnaeus, 1758 (Lepidoptera: Bombycidae) and Thyrinteina arnobia (Stoll, 1782) (Lepidoptera: Geometridae) were exposed to parasitism by females of P. elaeisis. The duration of the life cycle of P. elaeisis was 21.60 ± 0.16 and 24.15 ± 0.65 days on pupae of A. gemmatalis and B. mori, respectively, with 100.0% parasitism of the pupae and 71.4 and 100.0% emergence of parasitoids from the first and second hosts, respectively. The offspring number of P. elaeisis was 511.00 ± 49.70 and 110.20 ± 19.37 individuals per pupa of B. mori and A. gemmatalis, respectively. The reproduction of P. elaeisis from pupae of T. arnobia after six generations was similar to the other hosts.