Diferenças Morfológicas Regionais das Células Epiteliais ao Longo do Intestino Médio de Larvas deDiatraea saccharalis Fabricius (Lepidoptera: Crambidae)RESUMO -A broca da cana, Diatraea saccharalis Fabricius, é uma praga da cana-de-açúcar e outras plantações. O objetivo deste trabalho foi caracterizar variações morfológicas nas células epiteliais (colunares, caliciformes e regenerativas) ao longo do intestino médio de larvas de D. saccharalis. Fragmentos do intestino médio (anterior, mediano e posterior) foram fi xados e processados para microscopia de luz e eletrônica de varredura. Existem diferenças morfológicas citoquímicas e ultraestruturais nas células epiteliais, dependendo da sua localização no intestino médio. A superfície apical de algumas células colunares exibe projeções citoplasmáticas que aumentam em número e volume da região anterior para a posterior do intestino médio. Existe aumento dos grânulos PAS-positivos (Reação de Schiff) no citoplasma apical das células colunares e regenerativas, da região anterior para a posterior. A câmara das células caliciformes, na região anterior do intestino médio, mostra seu ápice estreito, enquanto que na posterior essa porção da câmara é alargada; as evaginações citoplasmáticas da câmara são pequenas e fi nas no ápice, sendo numerosas, longas e mais espessas na porção basal. Os resultados sugerem que o intestino médio da broca da cana apresenta duas regiões morfologicamente distintas, a anterior e posterior; a região mediana é uma região de transição.PALAVRAS-CHAVE: Morfologia, broca da cana, histoquímica, microscopia eletrônica de varredura, microscopia de luz ABSTRACT -The sugarcane borer, Diatraea saccharalis Fabricius, is a pest to sugarcane and many other crops. This work aims to characterize morphological variability in the epithelial cells (columnar, goblet and regenerative) along the midgut of D. saccharalis larvae. Fragments of the midgut (anterior, middle and posterior regions) were fi xed and processed by light and scanning electron microscopy. There are both cytochemical and ultrastructural differences in the morphology of the epithelial cells, depending on their localization along the midgut. The apical surface of columnar cells shows an increase in both number and size of the apical protrusions from the anterior to the posterior midgut regions.There is an increase in the amount of PAS-positive (Periodic Acid-Schiff Reaction) granules detected in the cytoplasm of both the columnar and regenerative cells, from the anterior to the posterior region. The goblet cell apical surface is narrow in the anterior region, and enlarged in the posterior midgut; the chamber's cytoplasm extrusion are small and thin at the apical cavity surface, being thicker, longer and more numerous at the basal portion of the cavity. Our results suggest that the sugarcane borer midgut has two morphologically different regions, the anterior and the posterior; the middle region is a transitional region.

PALAVRAS-CHAVE: Morfometria, célula epitelial, inseto, broca da cana, mesêntero ABSTRACT -The sugarcane borer, Diatraea saccharalis Fabricius, has great economical interest as it affects the culture and industrial use of the sugarcane. However, there are few studies concerning the internal morphology of this insect. This work aims to study morphometrically the midgut and the epithelium along their lenght, trying to characterize different regions. Midgut of last instar larvae was divided in three regions: anterior, middle and posterior, and the fragments were processed for light microscopic observation. Histological sections were analyzed in a computerized system concerning the length, width and area of the epithelium, their cells, and the midgut lumen. The obtained data were statistically analyzed by the Kruskal-Wallis test and by multivariate analysis. Our results showed that the midgut has two different regions, the anterior and the posterior; the middle region presents values that are coincident with the ones of either the anterior and the posterior portions, suggesting that there is an intermediate region between the other two ones. The epithelial cells (columnar, goblet and regenerative cells), when evaluated by multivariate analysis, do not present significant morphometric differences in the different midgut regions. However, the analysis of variance for separate variables show that the regenerative cells present wide morphometric variability along the midgut.

The sugarcane borer Diatraea saccharalis (Lepidoptera: Crambidae) has been controlled by Cotesia flavipes (Hymenoptera: Braconidae); however, very little is known about the effect of the parasitism in the host organs, including the midgut. This work aims to verify mitochondrial alteration in the different midgut epithelial cells of D. saccharalis parasitized by C. flavipes. Midgut fragments (anterior and posterior region) of both non-parasitized and parasitized larvae were processed for transmission electron microscopy. The mitochondria of midgut epithelial cell in the parasitized larvae exhibit morphological alteration, represented by matrix rarefaction and vacuolisation. These mitochondrial alterations are more pronounced in the anterior midgut region during the parasitism process, mainly in the columnar cell.Keywords: midgut, Diatraea saccharalis, mitochondria, Cotesia flavipes, epithelial cell. Mitocôndria nas Células Epiteliais do Intestino Médio da Broca-da-cana Parasitada por Cotesia flavipes ResumoDiatraea saccharalis (Lepidoptera: Crambidae), broca da cana-de-açúcar, tem sido controlada por Cotesia flavipes (Hymenoptera: Braconidae); pouco se sabe sobre o efeito do parasitismo nos diferentes órgãos do inseto hospedeiro, principalmente no intestino médio. O objetivo desse trabalho foi verificar as alterações mitocondriais das diferentes células epiteliais do intestino médio de larvas de D. saccharalis parasitadas por C. flavipes. Fragmentos do intestino médio (regiões anterior e posterior) de larvas de D. saccharalis não-parasitadas e parasitadas foram processados para microscopia eletrônica de transmissão. As mitocôndrias das células epiteliais do intestino médio de larvas parasitadas exibem alterações, especialmente rarefação e vacuolização da matriz, que foram mais pronunciadas nas células epiteliais da região anterior do intestino médio na vigência do parasitismo, em especial nas células colunares.Palavras-chave: intestino médio, Diatraea saccharalis, mitocôndria, Cotesia flavipes, célula epitelial.

Euschistus heros is an important pest in Brazilian agriculture growing importance in the general Neotropical realm. Its reproductive potential is the key factor for its characterization as a pest in major crops such as soybean and cotton. The aims of this study were to characterize morphometric parameters of testicles and testicular accessory cells-TACs nuclei of adults E. heros treated with chitin biosynthesis inhibitors (CBIs). The insecticides lufenuron (Match® 50 EC) and buprofezin (Applaud® 250 WP) were applied individually in 4th instar nymphs, remained in controlled conditions until the emergence of adult males. The testicles were identified and removed 72 h after emergency, fixed, photographed for anatomic analysis, and processed for morphometric analyses of the TACs nuclei. It was possible to observe that lufenuron and buprofezin decreased the testicular area. Buprofezin decreased the mean nuclear area analyzed in the TACs, and nuclear hypertrophy can indicate an activity on support and nutrition of germ line cells, presenting a possible effect on protein synthesis. The intense reaction for Fast green in control compared to buprofezin treatment may indicate that total protein (histones and non-histones) has been altered. The tested insecticides, with special focus on buprofezin may affect the final stages of reproductive development of E. heros, with potential to be used in field to the control of this pest.

Neotropical Entomology 36(5): 707-711 (2007) Evidências Histoquímicas e Ultra-Estruturais de Secreção Lipídica pela Glândula da Seda da Broca da Canade-Açúcar, Diatraea saccharalis (Fabricius) (Lepidoptera: Crambidae)RESUMO -A glândula da seda de larvas de Lepidoptera é responsável pela produção da seda usada na secreção de seda de insetos, embora a presença desse componente contribua para a resistência da seda secreção da glândula da seda de larvas de Diatraea saccharalis (Fabricius), bem como caracterizar a região glandular responsável pela secreção. A glândula da seda foi submetida a procedimentos histoquímicos para detecção de lipídeos e convencionalmente preparada para análise ultra-estrutural. Gotas lipídicas foram histoquimicamente detectadas no citoplasma apical de células da região anterior e no lúmen, entre os microvilos. A análise ultra-estrutural da região anterior mostrou material lipídico, visualizado como com sericina; material semelhante foi observado dentro do lúmen, adjacente aos microvilos. Nenhum componente secretor lipídico foi detectado nas células ou no lúmen da região posterior. Os resultados sugerem que a seda produzida pela D. saccharalis tem, pelo menos, um discreto componente lipídico, que é secretado pela região anterior, junto com a sericina.PALAVRAS-CHAVE: Célula secretora, inseto, larva, lipídio ABSTRACT -The silk gland in Lepidoptera larvae is responsible for the silk production used for shelter characterizes the glandular region and detects the presence of lipid components in the secretion of the silk gland of Diatraea saccharalis detected in both the apical cytoplasm of cell of the anterior region and in the lumen among the microvilli.neither in the lumen of the posterior region. Our results suggest that the silk produced by D. saccharalis

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Koinobiont parasitoids use several strategies to regulate the host's physiological processes during parasitism. Although many aspects of host-parasitoid interactions have been explored, studies that attempted to assess the effects of parasitism on the availability of inorganic elements in the host are virtually nonexistent. Therefore, we aimed to evaluate the effects of parasitism on the concentrations of inorganic elements in the fat bodies of larvae of Diatraea saccharalis (Lepidoptera: Crambidae) during the development of the parasitoid Cotesia flavipes (Hymenoptera: Braconidae), by using total reflection X-ray fluorescence (TXRF). TXRF analysis allowed comparisons of the changes in the availability of the elements P, S, K, Ca, Cr, Fe, Ni, Cu, and Zn in the fat body tissues of D. saccharalis larvae parasitized by C. flavipes. Overall, the concentration of inorganic elements was higher early in parasitoid development (1 and 3days after parasitism) compared to non-parasitized larvae, but much lower towards the end of parasitoid development (7 and 9days after parasitism). Ca, K, and S were reduced after the fifth day of parasitism, which affected the total abundance of inorganic elements observed in the fat bodies of the parasitized hosts. The regulatory mechanisms or pathological effects related to the observed variation of the host inorganic elements induced by the parasitoid remain unknown, but there might be a strategy to make these elements available to the parasitoid larvae at the end of their development, when higher metabolic activity of the host fat body is required to sustain parasitoid growth. The observed variation of the host's inorganic elements could also be related to the known effects of parasitism on the host's immune response.