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Leucaena leucocephala (Lam.) de Wit (Fabaceae) is widely used to regenerate degraded landscapes in tropical and subtropical regions and serves as a protein source for animals in agrosilvopastoral systems. Thus, our objective was to assess the spatial distribution of insects on the tree crown (vertical: upper, middle, and basal canopy; horizontal: north, south, east, and west) and leaf surfaces (adaxial and abaxial) of L. leucocephala. Phytophagous insects, natural enemies, and pollinators were quantified fortnightly in 20 trees for 2 yr. North-facing tree branches had the greatest numbers of phytophagous insects, natural enemies, and pollinators. Branches facing west had the most species-rich and biodiverse phytophagous and pollinator assemblages, whereas for natural enemies, species richness and biodiversity were greatest on branches facing north or south. The greatest numbers of individuals and highest levels of species richness of phytophagous insects, natural enemies, and pollinators were observed in the upper and middle parts of the L. leucocephala canopy. The most individuals and highest levels of species richness and biodiversity for phytophagous insects, natural enemies, and pollinators were observed on the abaxial face of L. leucocephala leaves. The species with the highest abundance and k-dominance (common or constant species) on L. leucocephala trees were the phytophagous insects Trigona spinipes F. (Hymenoptera: Apidae: Meliponinae) and Tropidacris collaris Stoll (Orthoptera: Romaleidae) and the natural enemies Camponotus sp.2 (Hymenoptera: Formicidae) and Brachymyrmex sp. (Hymenoptera: Formicidae). These results can inform strategies related to pest control and maintenance of natural enemies and pollinators in L. leucocephala plantations. Biopesticide application, for example, may be more effective at eliminating target organisms if directly applied on their preferred sites, and a targeted application can minimize negative effects for non-target organisms.

RESUMO:O objetivo deste trabalho foi avaliar o efeito da omissão de nutrientes nas mudas de Lippia sidoides Cham. (Verbenaceae) e seu possível efeito sobre os seus artrópodes, sendo os tratamentos: 1) testemunha; 2) completo 1 adubado com N, P, K, S, B, Cu, e Zn + calagem (C1); 3) completo 2: C1 sem calagem + Ca e Mg como sulfato (C2); 4) C1 sem calagem; 5) C1 sem N; 6) C1 sem P; 7) C1 sem K; 8) C1 sem S; 9) C1 sem B; 10) C1 sem Cu; 11) C1 sem Zn; 12) C2 sem Ca e 13) C2 sem Mg. O delineamento foi inteiramente casualizado com quatro repetições. O Tetranychus sp. (Acari: Tetranychidae) atacou mais os tratamentos 3, 6, 9 e 13 e os maiores danos nos tratamentos 6 e 13. A maior população de Aphis gossypii Glover (Homoptera: Aphididae) foi encontrada nos tratamentos 5, 6, 7, 8, 11 e 13, colonizando preferencialmente o tratamento 4. O Phenacoccus sp. (Hemiptera: Pseudococcidae) foi encontrado em maior número nos tratamentos 4 e 9 e Insignorthezia insignis (Browne) (Hemiptera: Ortheziidae) em 13. Foram mais notados adultos de Bemisa tabaci (Genn.) (Hemiptera: Aleyrodidae) nos tratamentos 5, 7, 8 e 13 e ninfas nos três últimos tratamentos. Em geral, os tratamentos 1, 5 e 10 são os menos atacados por artrópodes. Dirigir a pulverização, quando necessário, sempre para a face inferior da folha. Palavras-chaves: plantas medicinais, adubação, insetos, ácarosABSTRACT: Nutrients affecting "alecrim-pimenta" (Lippia sidoides Cham.) seedlings and their arthropods. The aim of this work was to evaluate nutrient omission effect on Lippia sidoides Cham. (Verbenacea) seedlings, as well as its possible effect on their arthropods. Treatments were: 1) control; 2) complete 1: fertilized with N, P, K, S, B, Cu, and Zn + lime (C1); 3) complete 2: C1 without lime + Ca and Mg as sulphate (C2); 4) C1 without lime; 5) C1 without N; 6) C1 without P; 7) C1 without K; 8) C1 without S; 9) C1 without B; 10) C1 without Cu; 11) C1 without Zn; 12) C2 without Ca; and 13) C2 without Mg. The experimental design was completely randomized, with four replicates. Tetranychus sp. (Acari: Tetranychidae) predominantly attacked treatments 3, 6, 9 and 13, and the greatest damages were detected in treatments 6 and 13. The largest population of Aphis gossypii Glover (Homoptera: Aphididae) was observed in treatments 5, 6, 7, 8, 11 and 13, preferentially colonizing treatment 4. Phenacoccus sp. (Hemiptera: Pseudococcidae) was predominant in treatments 4 and 9, and Insignorthezia insignis (Browne) (Hemiptera: Ortheziidae), in treatment 13. Bemisia tabaci (Genn.) (Hemiptera: Aleyrodidae) adults were mostly detected in treatments 5, 7, 8 and 13, whereas nymphs, in the last three treatments. In general, treatments 1, 5 and 10 are the least attacked by arthropods. When needed, pulverization must always be directed to the leaf lower surface.

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