Arthropod fauna on the abaxial and adaxial surfaces of Acacia mangium (Fabaceae) leaves / Fauna de artrópodes nas superfícies abaxial e adaxial de folhas de Acacia mangium (Fabaceae)

Acacia mangium (Willd., 1806) (Fabales: Fabaceae) is a fast growing, rustic, pioneer species, with potential to fix nitrogen, and for programs to recover degraded areas. The objective was to evaluate the distribution and the functional diversity of interactions and the K-dominance of arthropod groups on A. mangium saplings. The number of individuals of eleven species of phytophagous insects, three bee species, and fourteen natural enemy species were highest on the adaxial leaf surface of this plant. Abundance, diversity and species richness of phytophagous insects and natural enemies, and abundance and species richness of pollinators were highest on the adaxial A. mangium leaf surface. The distribution of five species of sap-sucking hemipterans and six of protocooperating ants (Hymenoptera), with positive interaction between these groups, and three bee species (Hymenoptera) were aggregated on leaves of A. mangium saplings. Aethalion reticulatum (L.) (Hemiptera: Aethalionidae) and Bemisia sp. (Hemiptera: Aleyrodidae); Brachymyrmex sp. and Camponotus sp. (Hymenoptera: Formicidae); and Trigona spinipes Fabricius (Hymenoptera: Apidae) were the most dominant phytophagous insects, natural enemies, and pollinators, respectively, on A. mangium leaves. Knowledge of preferred leaf surfaces could help integrated pest management programs.

Acacia mangium (Willd., 1806) (Fabales: Fabaceae) é uma planta pioneira com rápido crescimento, rusticidade, potencial nitrificador e importante em programas de recuperação de áreas degradadas. O objetivo foi avaliar a distribuição e a diversidade funcional das interações e a dominância-K de grupos de artrópodes em árvores jovens de A. mangium. Os números de indivíduos de onze espécies de insetos fitófagos, três de abelhas e quatorze de inimigos naturais foram maiores na superfície adaxial de folhas dessa planta. A abundância, diversidade e riqueza de espécies de insetos fitófagos e inimigos naturais, e a abundância e riqueza de espécies de polinizadores foram maiores na face adaxial de folhas de A. mangium. A distribuição de cinco espécies de hemípteros sugadores de seiva e seis de formigas protocooperantes (Hymenoptera), com interação positiva entre esses grupos, e três de abelhas (Hymenoptera) foi agregada em folhas de plantas jovens de A. mangium. Aethalion reticulatum (L.) (Hemiptera: Aethalionidae) e Bemisia sp. (Hemiptera: Aleyrodidae); Brachymyrmex sp. e Camponotus sp. (Hymenoptera: Formicidae); e Trigona spinipes Fabricius (Hymenoptera: Apidae) foram os insetos fitófagos, inimigos naturais e polinizadores mais dominantes, respectivamente, em folhas de A. mangium. A definição da superfície foliar preferida pode auxiliar programas de manejo integrado de pragas.

Pathological alterations in the ovaries of culex pipiens induced by fixed oil extracts from thevetia peruvine, datura stramonium and acacia sp

The fixed oil extracts from Thevetia peruvine, Datura stramonium and Acacia sp were tested on Culex pipiens larvae. The estimated sublethal concentrations [LC50] were used in the present study. The reproductive potential of females and the histochemistry of their ovaries were determined. The results indicated that oil treatments of larvae caused drastic changes in reproduction potential of female mosquito including the ovarian development in the first gonotrophic cycle, fecundity and fertility of treated females. Histological and histochemical studies revealed clear changes in the oocytes of females derived from treated larvae. Treatment with the oils reduced the vitellogenesis, synthesis of proteins, carbohydrates, lipid contents, DNA and RNA materials. The reproduction was always significant and may reflect the shortage in reproductive potential, the state of being disturbed. Generally, these fixed oils merit further investigations as a potential suppressant of Culex pipiens because their abilities to kill the early stages inhibit growth and development of ovaries and reduce the reproductive potential of adult females. The three oils have variable activities but they are similar in their mode and site of actions