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Essential oils from leaves and fruits of Protium heptaphyllum collected in Tamandaré beach -Pernambuco/Brazil were analysed by GC/MS and tested for toxicity and repellent effect against the two spotted spider mite (Tetranychus urticae). The major constituent identified in the fruits was a-terpinene (47.6 %) whereas oil from leaf contained mainly sesquiterpenes such as 9-epi-caryophyllene (21.4 %), trans-isolongifolanone (10.7 %) and 14-hydroxi-9-epi-caryophyllene (16.7 %). The fruit oil was found to be more effective against the mite when compared to the leaf oil. Both showed mortality properties and oviposition deterrence in higher concentration (10 Fl.l -1 air), but only the essential oil from fruits induced repellence on T. urticae. KEY-WORDSProtium heptaphyllum, essential oil, Tetranychus urticae, acaricidal activityComposição química e atividade acaricida do óleo essencial das folhas e frutos de Protium heptaphyllum (Aubl.) Marchand (Burseraceae) 1 RESUMO O óleo essencial das folhas e frutos de Protium heptaphyllum coletada em Tamandaré-Pernambuco foi analisado por CG/EM e testado sua toxicidade e efeito repelente contra ácaro rajado (Tetranychus urticae). O constituinte majoritário identificado nos frutos foi a-terpineno(47,6 %) enquanto que nas folhas foram os sesquiterpenos 9-epi-cariofileno (21,4 %), trans-isolongifolanona (10,7 %) and 14-hidroxi-9-epi-cariofileno (16,7 %)

Recebido em 13/4/06; aceito em 30/8/06; publicado na web em 26/3/07 ACARICIDAL ACTIVITY OF the ESSENTIAL OILS OF LEAVES AND FRUITS OF Xylopia sericea St. Hill. ON THE TWO SPOTTED SPIDE MITE (Tetranychus urticae Koch). The essential oils of the leaves and fruits obtained by hydrodistillation of Xylopia sericea, collected in the restinga area of Pernambuco, were analyzed by GC (HP 5890 SERIES II) and GC/MS (HP 5890B SERIES II/ MSD 5971). A major part of the volatile components identified in the oils of fruits and leaves were monoterpenes and sesquiterpenes. Cubenol (57.43%) and α-epi-muurolol (26.09%) were the main compounds found in the leaves, whereas β-pinene (45.59%) and α-pinene (17.18%) were the fruits major components. The acaricidal activity of the essential oils was evaluated for Tetranychus urticae. The oil of the leaves was more active than that of the fruits showing an LC 50 value of 4.08 μL/L of air for a 72 h period.

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Recognition and acceptance of a suitable host plant by phytophagous insects requires the integration of visual, physical and chemical cues. The present study investigates the host cues that a specialist insect integrates to optimize oviposition decisions and whether these cues are weighted in a specific way. The study also determines whether the tomato fruit borer Neoleucinodes elegantalis (Guenée) (Lepidoptera: Crambidae), an important pest on Solanaceae in Brazil, shows a preference for oviposition sites that differ in physical and/or chemical cues. When styrofoam balls are provided as artificial fruits, N. elegantalis deposit significantly more eggs on rough artificial fruits than on smooth ones. Hexane fruit extracts applied to the artificial fruits stimulate female oviposition strongly. Physical and chemical cues also affect the oviposition of females when offered together. Furthermore, certain parts of the artificial fruits are prefered, irrespective of the presence of chemical cues. Both physical and chemical cues affect oviposition decisions; hence, the fruit borer relies on cues of different sensory modalities.

Coccinellids can exploit a wide variety of foods and other sources of nutrients to supplement their diet. The use of these secondary sources of food, is called an alternative diet. Some species are able to maintain their development and reproduction by feeding exclusively on an alternative diet, while the fecundity of others are compromised. One of the major sources of alternative food exploited by predator coccinellids is pollen. The aim of this research is test the hypothesis that pollen affects the fecundity of the B. foudrasii. A group of females were fed with nymphs and adults of F. dasylirii mealybug. A second groupe were feed with F. darsylirii along with pollen, and a third group was fed only pollen. All female beetles were observed for 10 days. The eggs were counted and the females were dissected, to access oocyte maturation. The results showed that only females fed with mealybugs oviposited. These females had an average of 18.9 mature oocytes. Females fed with the mix of mealybugs and pollen had an average of 17.4 mature oocytes. Females fed exclusively pollen had no mature oocytes. Our results suggest that pollen appeared to exert an inhibitory effect and oviposition behavior.

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