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The gall wasp, Leptocybe invasa, poses a significant global threat to Eucalyptus cultivation, by causing substantial economic losses. The objective of this study was to differentiate between resistant and susceptible genotypes by morphological characteristics using image analysis based on the damage caused by the gall wasp. In addition, consensus sequences derived from transposable elements (TEs) and the genome of Eucalyptus spp. Were identified by in silico analysis. Furthermore, another objective was to discriminate Eucalyptus genotypes in response to Leptocybe invasa by conducting molecular analyses involving transposable elements and inter simple sequence markers. For image analysis, the GroundEye ® system was used to collect images of 60 leaves from six genotypes, three of which were resistant and three susceptible. Eucalyptus spp. sequences were obtained from the GenBank database by in silico analysis and pairwise alignments with TE sequences were conducted using BLASTN. Multiple sequence alignment was performed with Clustal Omega, followed by the identification of conserved regions in Jalview. A motif signature was generated using Weblogo. For molecular characterization using ISSR markers and TEs, samples of young leaves were obtained from a total of 80 Eucalyptus seedlings, of which 50 were classified as resistant and 30 as susceptible to L. invasa. It was possible to distinguish gall wasp susceptible and resistant genotypes by image analysis. In silico analysis enabled the identification of conserved regions in the Eucalyptus spp. genome, which were associated with proteins involved in secondary metabolite production, e.g., terpenes, which play a role in the response to L. invasa. The discrimination capacity of TEs and ISSR primers was demonstrated and bands were generated that could be used to identify resistant genotypes. However, increasing the number of markers required to discriminate genotypes in both cases is suggested.

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The red gum lerp psyllid, Glycaspis brimblecombei Moore, 1964 (Hemiptera: Aphalaridae), an insect pest originating in Australia and which feeds only on Eucalyptus L'Hér. (Myrtales: Myrtaceae) plants, has spread to several countries. The populations of this insect commonly reach high populations on Eucalyptus plants since its entry into Brazil, and also indicated an unrecorded behavioral. The objectives of this study were to describe a peculiar adaptation in the feeding habit of G. brimblecombei and to register the new habit. The oviposition and feeding by G. brimblecombei, commonly, on the leaves of Eucalyptus, started to occur, also, on lignified twigs. This suggests a not yet recorded adaptation of this insect to reduce insect × plant intraspecific competition.

O psilídeo de concha, Glycaspis brimblecombei Moore, 1964 (Hemiptera: Aphalaridae), um inseto praga originário da Austrália e que se alimenta apenas de plantas de Eucalyptus L'Hér. (Myrtales: Myrtaceae), se espalhou por vários países. Esse inseto, geralmente, atinge grandes populações em plantas de Eucalyptus desde sua entrada no Brasil e, também, indicou um comportamento diferente. Os objetivos deste estudo foram descrever uma adaptação peculiar no hábito alimentar de G. brimblecombei e registrar o novo hábito. A oviposição e alimentação por G. brimblecombei, geralmente, nas folhas de Eucalyptus, passaram a ocorrer, também, em ramos lignificados. Isso sugere uma adaptação diferente desse inseto para reduzir a competição intraespecífica inseto × planta.

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The Brazilian forestry sector stands out for its technology, forestry management practices, social and environmental responsibility and, mainly, for its high productivity and exotic pests can reduce it. The red gum lerp psyllid Glycaspis brimblecombei (Moore, 1964) (Hemiptera: Aphalaridae) is an important pest in Eucalyptus plantations. The parasitoid Psyllaephagus bliteus (Riek, 1962) (Hymenoptera: Encyrtidae), predatory bugs and entomopathogenic fungi such as Beauveria bassiana and Metarhizium anisopliae are the natural enemies and used in the biological control of the red gum lerp psyllid. The use of entomopathogenic fungi against exotic pests is increasing in the forestry sector and the prospecting and identification of fungus isolates is important for integrated pest management. The objective of this work was the isolation and molecular identification of Cordyceps spp. And to evaluate the pathogenicity of isolates, obtained from Bemisia tabaci (Gennadius, 1889) (Hemiptera: Aleyrodidae) adults, against to the red gum lerp psyllid G. brimblecombei. The fungi were isolated from B. tabaci adults found in soybean and tomato crops and molecularly identified. The conidia obtained were suspended in solution with Tween 80 (0.1%) at a concentration of 1.0 × 108 conidia/mL and sprayed on ten G. brimblecombei nymphs per Eucalyptus leaf cut and placed on a hydroretentive gel inside per Petri dishes as a replication. The number of dead insects was quantified, daily, for seven days, and transferred to humid chambers. Cordyceps javanica (LCBPF 11) and C. fumosorosea (LCBPF 12 and LCBPF 63) were identified with a molecular analysis and all isolates were pathogenic to the insects and indicates that they could be used to manage G. brimblecombei and adds to reports that, normally, fungi cause greater mortality on insects of the same order as that from which they were isolated.

O setor florestal brasileiro se destaca pela tecnologia, práticas de manejo florestal, responsabilidade social e ambiental e, principalmente, alta produtividade, mas pragas exóticas podem reduzir isto. O parasitoide Psyllaephagus bliteus (Riek, 1962) (Hymenoptera: Encyrtidae), percevejos predadores e fungos entomopatogênicos como Beauveria bassiana e Metarhizium anisopliae são inimigos naturais usados no controle biológico do psilídeo-de-concha do eucalipto Glycaspis brimblecombei (Moore, 1964) (Hemiptera: Aphalaridae), praga em plantios de eucalipto. A utilização de fungos entomopatogênicos contra pragas exóticas vem aumentando no setor florestal e a prospecção e identificação de isolados fúngicos é importante para o manejo integrado de pragas. O objetivo deste estudo foi o isolamento e identificação molecular de Cordyceps spp. e avaliar a patogenicidade dos isolados de Cordyceps javanica (LCBPF 11) e Cordyceps fumosorosea (LCBPF 12 e LCBPF 63), obtidos de adultos de Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae), ao psilídeo-de-concha G. brimblecombei. Os fungos foram isolados de adultos de B. tabaci encontrados em culturas de soja e tomate e identificados molecularmente. Os conídios foram suspensos em solução com Tween 80 (0,1%) na concentração de 1,0 x 108 conídios/mL e pulverizados sobre dez ninfas de G. brimblecombei por folha de Eucalyptus cortada e colocada sobre gel hidrorretentor no interior de placas de Petri por repetição. O número de insetos mortos foi quantificado, diariamente, por sete dias e transferidos para câmaras úmidas. Cordyceps javanica (LCBPF 11) e C. fumosorosea (LCBPF 12 e LCBPF 63) foram identificados por análise molecular e todos os isolados foram patogênicos para os insetos. Isto indica serem importantes para o manejo de G. brimblecombei e confirma relatos de que, normalmente, fungos causam maiores mortalidades em insetos da mesma ordem daquela da qual foram isolados.

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Areas planted with Eucalyptus urophylla S.T. Blake variety platyphylla F. Muell. (Myrtaceae) expand annually in most regions of Brazil. Many lepidopteran species defoliate this plant, but with damage varying per species. The objective of this study was to identify the pest status of lepidopteran defoliators based in the faunistic analysis of these insects and of their natural enemies on E. urophylla variety platyphylla plantations in a representative producing region of Brazil. Adult moths of lepidopterans and of their natural enemies were captured using a light trap, installed every two weeks, from September 2016 to August 2018. A total of 183, 10, three and 139 lepidopteran species was captured and classified as primary, secondary, without defined importance to eucalypt plants and non-identified with 1,419, seven, 465 and 876 individuals, respectively. Two primary pest species were constants, two accessories and six accidentals and all secondary ones were accidentals. Six primary pest species were common and dominant and four non-dominants. Faunistic indices indicated the main lepidopteran species that should be monitored in pest management programs. Seven hymenopteran species (65 individuals), three dipterans (49 individuals) and two hemipterans (four individuals) were the natural enemies collected using light traps. The monitoring of lepidopteran pests with light traps can contribute to the management and to reduce damage and control costs for these species, besides identifying natural enemies for biological control programs in Eucalyptus plantations.

Áreas plantadas com Eucalyptus urophylla S.T. Blake variedade platyphylla F. Muell. (Myrtaceae) se expandem anualmente na maioria das regiões do Brasil. Muitas espécies de lepidópteros desfolham esta planta, mas com danos que variam de acordo com a espécie. O objetivo deste estudo foi identificar o status de praga de lepidópteros desfolhadores com base na análise faunística desses insetos e de seus inimigos naturais em plantios de E. urophylla variedade platyphylla em uma região produtora representativa do Brasil. As mariposas e seus inimigos naturais foram capturadas com armadilha luminosa, instalada quinzenalmente, de setembro de 2016 a agosto de 2018. Um total de 183, 10, três e 139 espécies de lepidópteros foram capturadas e classificadas como primária, secundária, sem importância definida para eucaliptocultura e não identificadas com 1419, sete, 465 e 876 indivíduos, respectivamente. Duas espécies de pragas primárias foram constantes, duas acessórias e seis acidentais e todas as secundárias foram acidentais. Seis espécies de pragas primárias foram comuns e dominantes e quatro não dominantes. Os índices faunísticos indicaram as principais espécies de lepidópteras que devem ser monitoradas em programas de manejo de pragas. Sete espécies de himenópteros (65 indivíduos), três dípteros (49 indivíduos) e dois hemípteros (quatro indivíduos) foram os inimigos naturais coletados com armadilha luminosa. O monitoramento de lepidópteros-praga com armadilha luminosa pode contribuir para o manejo e redução de danos e custos de controle para essas espécies, além de identificar inimigos naturais para programas de controle biológico em cultivos de eucalipto.

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The adaptation of native lepidopteran species to eucalyptus plantations reduces the productivity of this crop in Brazil. Oxydia vesulia Cramer (Lepidoptera: Geometridae) is a secondary pest, frequently reported in eucalyptus plantations with population outbreaks and economic damages. Methods of biological control of this pest may include the use of the exotic pupae endoparasitoid Tetrastichus howardi Olliff (Hymenoptera: Eulophidae), reported as efficient to controlling lepidopteran pests. The parasitism of O. vesulia caterpillars and pupae by T. howardi was evaluated under controlled conditions (25 ± 1 ºC, 60 ± 20% humidity and 12:12 h L:D). Each O. vesulia caterpillar or pupae was individually placed in a flat-bottom tube with 10 and 15 females of T. howardi for 48h, respectively. The parasitoids were removed after that period, the caterpillars were fed and the pupae were maintained until emergence of the parasitoid or formation of pupae and emergence of adults of this pest. The fourth-instar caterpillars of O. vesulia, after the parasitism period, were kept in pots with Eucalyptus urophylla leaves, changed daily until the end of the experiment. A total of 40% of the caterpillars died before the pre-pupae stage, 40% reached the pupae stage and died due to inadequate adult formation and 20% generated moths, but none adult parasitoid emerged from the caterpillars. All pupae of O. vesulia were parasitized and showed emergence of parasitoids. The parasitism of O. vesulia caterpillars and pupae by T. howardi shows the potential of this natural enemy for the integrated management of this defoliator pest in eucalyptus plantations.(AU)

A adaptação de espécies nativas de lepidópteros a plantios de eucalipto reduz a produtividade dessa cultura no Brasil. Oxydia vesulia Cramer (Lepidoptera: Geometridae) é praga-secundária, frequentemente, relatada em plantios de eucalipto com surtos populacionais e danos econômicos. Métodos de controle biológico, dessa praga, podem incluir o uso do endoparasitoide exótico de pupas Tetrastichus howardi Olliff (Hymenoptera: Eulophidae) relatado como eficiente para o controle de lepidópteros-pragas. O parasitismo de lagartas e pupas de O. vesulia por T. howardi foi avaliado em condições controladas (25 ± 1º C, 60 ± 20% umidade e 12h fotoperíodo). Cada lagarta ou pupa de O. vesulia foi colocada individualmente em tubos de fundo chato com 10 e 15 fêmeas de T. howardi por 48h, respectivamente e, após esse período, os parasitoides foram removidos, as lagartas alimentadas e as pupas mantidas até a emergência do parasitoide ou formação de pupas ou de adultos dessa praga. As lagartas de quarto ínstar de O. vesulia, após o período de parasitismo, foram mantidas em potes com folhas de Eucalyptus urophylla trocadas, diariamente, até o fim do experimento. Um total de 40% das lagartas de O. vesulia morreu antes da fase de pré-pupa, 40% atingiram o estágio de pupa e morreram devido à má formação ou problemas e 20% originaram mariposas, porém nenhum parasitoide adulto emergiu das lagartas. Todas as pupas de O. vesulia foram parasitadas e tiveram emergência de parasitoides. O parasitismo de lagartas e pupas de O. vesulia por T. howardi mostra o potencial desse inimigo natural para o manejo integrado desse desfolhador em cultivos de eucalipto.(AU)

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