Resumen Nasutitermes corniger es una termita arbórea que causa daños económicos en las zonas urbanas, y su control es mediante insecticidas químicos. Una alternativa para el control de insectos es el uso de hongos entomopatógenos y extractos de plantas, o el efecto sinérgico de la asociación de estos. Se examinó la toxicidad de los extractos acuosos e hidroetanólicos de Agave sisalana sobre los aspectos biológicos de los hongos Cordyceps farinosa, C. fumosorosea y C. javanica y la acción de los extractos y su efecto sinérgico sobre N. corniger. Se evaluó el efecto de los extractos sobre hongos por germinación, esporulación y crecimiento micelial de los hongos en medio Sabouraud mediante el estudio de aspectos biológicos bajo condiciones de laboratorio y se examinó el control de N. corniger, por ingestión de extractos y de la asociación extracto y hongo sobre papel de filtro, siendo el porcentaje de mortalidad de soldados y obreras de la termita diaria. En general, los extractos resultaron inofensivos para los hongos a concentraciones de 10, 25, 50, 100 y 200 mg.mL-1. Los extractos demostraron acciones termiticidas a las concentraciones ensayadas, provocando la mortalidad de alrededor del 100% de los trabajadores después del tercer y sexto día (LC50: 0.778 a 0.803 mg.mL-1) y del 100% de los soldados entre el cuarto y séptimo días (LC50: 0.146 a 0.956 mg.mL-1). La asociación de los extractos con C. farinosa ESALQ1355 fue más eficiente para inducir la mortalidad en N. corniger. Estos resultados demostraron la eficiencia in vitro de los extractos de sisal en el control de las termitas de N. corniger, solas o en combinación con hongos, lo que sugiere su potencial utilidad conjunta en el control biológico de plagas de insectos.

Abstract Nasutitermes corniger is an arboreal termite that causes economic damage in urban areas, and its control is for chemical insecticides. An alternative for insect control is the use of entomopathogenic fungi and plant extracts, or the synergistic effect of the association of these. The toxicity of aqueous and hydroethanolic extracts of Agave sisalana on the biological aspects of the fungal Cordyceps farinosa, C. fumosorosea and C. javanica and the action of the extracts and their synergistic effect on N. corniger was examined. The effect of the extracts on fungi was evaluated by germination, sporulation and mycelial growth of fungi in Sabouraud medium through the study of biological aspects under laboratory conditions; and control of N. corniger were examined, by ingestion of extracts and of the association extract plus fungus on filter paper, being the percentage of mortality of soldiers and workers of the termite daily. In general, the extracts were inoffensive to the fungi at concentrations 10, 25, 50, 100 and 200 mg.mL-1. The extracts demonstrated termiticidal actions at concentrations tested, causing the mortalities about 100% of the workers after the third and sixth days (LC50: 0.778 to 0.803 mg.mL-1) and 100% of the soldiers between the fourth and seventh days (LC50:0.146 to 0.956 mg.mL-1). The association of the extracts with C. farinosa ESALQ1355 was more efficient in inducing the mortality in N. corniger. These results demonstrated the efficiency in vitro of the sisal extracts in controlling N. corniger termites, alone or in combination with fungi, suggesting their potential joint usefulness in the biological control of insect pests.

ABSTRACT We compared the termite assemblages of different ecosystems in a humidity gradient. Three areas were sampled: (i) a humid montane forest; (ii) a hillside forest where shaded coffee (Coffea arabica Linnaeus, 1753) is cultivated; (iii) a seasonally dry forest (Caatinga). Active collection protocols were employed in each area during the dry and rainy seasons. The species were grouped according to their habitats and feeding habits. A total of 45 termite species belonging to 20 genera and three families were encountered. The termite fauna of the Caatinga was as rich and abundant as that of the humid forest areas, but it was distinct from it in species composition. Most termite species encountered in the montane forest were also found in the agro-ecological site, but some species were only found in the latter. The termite fauna of the Caatinga varied seasonally the most, with significantly reduced abundance during the dry period. When species richness, abundance, and species composition were considered together the climatic seasons were not found to significantly affect the termite faunas in any of the study areas. The numbers of encounters per feeding group and per habitat exploited did not differ among the different areas, or during the different seasons. Even in adjacent areas, the humidity gradient, as well as the vegetational characteristics, are reflected in differences in the termite fauna. Agro-ecological regimes can be considered viable alternatives to traditional methods of cultivation as they largely conserve the biodiversity found in non-modified environments.

Este trabalho teve como objetivo avaliar os efeitos de Metarhizium anisopliae, sobre Diatraea flavipennella e investigar sua resposta imune. Foi observado o efeito de M. anisopliae sobre lagartas de D. flavipennella, pulve-rizado nas concentrações de 103, 104, 105 conídios/mL, no qual apresentou diferenças com relação ao período larval, prolongando até 72,0 dias nos tratamentos e 25,0 dias na testemunha. Os resultados referentes aos hemócitos revelaram que as células mais frequentes quando pulverizado nas concentrações de 103, 105, 107 conídios/mL foram prohemócitos, esferulócitos, plas-mócitos e granulócitos, em relação aos adipohemócitos e oenocitóides. O nível de oxido nítrico apresentou diferença entre a testemunha e a concentração 107 conídios/mL (24h), enquanto a atividade de fenoloxidase foi semelhante entre os tratamentos em 24h e superior na concentração 107 conídios/mL (60h). No perfil bioquímico dos hemócitos, houve uma alteração em carboidratos, lipídios e proteínas em reação ao fungo. Os resultados indicam que o fungo M. anisopliae pode ser utilizado no Manejo Integrado de D. flavipennella, por apresentar patogenicidade e interferir no seu desenvolvimento mesmo quando expostas a pequenas concentrações.

This work aimed to evaluate the effects of Metarhizium anisopliae on Diatraea flavipennella and investigate their immune response. Was observed the effect of M. anisopliae against larvae of D. flavipennella sprayed at concentrations of 103, 104, 105 conidia / mL, in which showed differences relative the larval period, extending up to 72.0 days in treatment and 25.0 days in the control. The results for hemocytes revealed that the most frequent cells when sprayed at the concentrations of 103, 105, 107 conidia / mL were the prohemocytes, spherulocytes, plasmatocytes and granulocytes in relation to adipohemocytes and oenocytoids. The level of nitric oxide was different between the control and the concentration 107 spores / mL (24), while the activity of phenoloxidase was similar among treatments in 24 and higher concentration 107 spores / mL (60h). In biochemical profile of hemocytes was a change in carbohydrates, lipids and proteins in response to the fungus. The results indicate that the fungus M. anisopliae can be used in the Integrated Management of D. flavipennella by presenting pathogenicity and interfere with their development even when exposed to small concentrations.

Coptotermes gestroi (Wasmann) é considerada uma das espécies mais destrutivas de cupins subterrâneos, por causar danos a edificações, à arborização urbana e a culturas. Uma alternativa para o controle desse inseto pode ser o uso de agentes biocontroladores, como os fungos entomopatogênicos. Isaria (Persoon) tem sido indicado no controle de térmitas subterrâneos, inclusive do gênero Coptotermes. Dessa forma, o presente trabalho teve como objetivo selecionar isolados de Isaria patogênicos ao cupim C. gestroi. Os insetos pulverizados com suspensões fúngicas de I. farinosa, I. fumosoroseae I. javanica foram avaliados diariamente para a determinação da mortalidade. Todos os isolados foram patogênicos, ocasionando mortalidade acima de 70%, e virulentos, apresentando uma sobrevivência média de 2,0 a 3,9 dias. Contudo, os isolados ESALQ-1205 de I. farinosa, ESALQ-1296 de I. fumosorosea e os isolados URM-4995 e URM-4993 de I. javanica mostraram-se mais virulentos. A CL50estimada para os isolados ESALQ-1205 de I. farinosa, URM-4995 de I. javanica e ESALQ-1296 de I. fumosorosea resultou em valores de 3,7 x 105, 1,4 x 106e 2,7 x 106conídios mL-1, respectivamente. Tais resultados confirmam a eficiência dos isolados testados sobre os operários de C. gestroi. No entanto, novos estudos são necessários para verificar a melhor forma de utilização, bem como a sua efetividade em campo.

Coptotermes gestroi (Wasmann) is considered to be one of the most destructive species of subterranean termites because of the damage caused on edifications, urban trees, and crops. One alternative to control it is the use of biocontrol agents, such as the entomopathogenic fungi. The genus Isaria (Persoon) has been suggested for the control of subterranean termites, including the Coptotermes genus. Therefore, the present work aim was to select isolates of Isaria pathogenic to C. gestroi. The workers were sprayed with fungi suspensions of I. farinosa, I. fumosoroseaand I. javanica, and evaluated every day to determine mortality. All isolates were pathogenic towards C. gestroi with mortality rates higher than 70%, and virulent, with mean of survival of 2.0 up to 3.9 days. Among the isolates, the ESALQ-1205 isolate of I. farinosa, the ESALQ-1296 isolate of I. fumosorosea, URM-4995 and URM-4993 isolates of I. javanica showed the highest virulence. The estimated CL50 for the ESALQ-1205 isolate of I. farinosa, URM-4995 isolate of I. javanica and ESALQ-1296 isolate of I. fumosorosea was 3.7 x 105, 1.4 x 106and 2.7 x 106 conidia mL-1, respectively. These results suggest high efficiency of these isolates towards the C. gestroi workers. Nevertheless, further studies are necessary to determine a way of using them as well as their efficacy in field.

A ação de Metarhizium anisopliae var. anisopliae e Metarhizium anisopliae var. acridum sobre o cupim de montículo Nasutitermes coxipoensis (Holmgren) e a produção de conídios sobre os insetos mortos foram estudadas em laboratório. Doses infectivas foram determinadas através do contato direto dos insetos com a cultura fúngica após 12 dias de crescimento e quantificação dos conídios em câmara de Neübauer. Foram utilizadas as doses 0,5 x 10(6) e 1,6 x 10(7) conídos/ml, para M. anisopliae var. anisopliae, e 1,4 x 10(5) e 1,8 x 10(6) conídios/ml para M. anisopliae var. acridum, nominadas dose A e dose B, respectivamente. As doses corresponderam a 3 min. e 15 min. de contato direto de 20 cupins com a cultura fúngica. A produção de conídios foi avaliada utilizando-se insetos inoculados com o fungo, 10 dias após a morte. Os bioensaios foram realizados em triplicata. Os percentuais de mortalidade acumulada de N. coxipoensis tratados com M. anisopliae, no terceiro dia após a inoculação, foram: controle, 15,7%; dose A 95,7% e dose B 100%; para M. anisopliae var. acridum foram: controle, 13,3%; dose A 66,4 e dose B 88,8%. A média da produção de conídios foi mais elevada para M. anisopliae var. anisopliae do que para M. anisopliae var. acridum. Os resultados mostraram que M. anisopliae var. anisopliae apresentou maior potencial para o controle biológico de N. coxipoensis.

The action of Metarhizium anisopliae var. anisopliae and Metarhizium anisopliae var. acridum on the mound termite Nasutitermes coxipoensis (Holmgren) and the conidia production on dead insects were studied in laboratory. Infective doses were determined through direct contact of the insects with the fungi cultures with 12 days of growth followed by conidia quantification in Neübauer camera. The doses of 0.5 x 10(6) and 1.6 x 10(7) conidia/ml of M. anisopliae var. anisopliae, and 1.4 x 10(5) e 1.8 x 10(6) conidia/ml of M. anisopliae var. acridum were named dose A and dose B, for each fungus, respectively. These doses corresponded to 3-min and 15-min direct contact of 20 insects with the fungi cultures. Conidia production was evaluated using the insects inoculated with fungi. The bioassays were carried out in triplicate. The percentage of accumulated mortality of N. coxipoensis treated with M. anisopliae var. anisopliae on the third day after inoculation were: control, 15.7%; dose A 95.7% and dose B 100%; for M. anisopliae var. acridum: control, 13.3%; dose A 66.4% and dose B 88,8%. The average of conidia production was higher for M. anisopliae var. anisopliae than M.anisopliae var. acridum. The results showed that M. anisopliae var. anisopliae presented better potential for the biological control of N. coxipoensis.