Genetic diversity, population structure and ecological niche modeling of Thyrinteina arnobia (Lepidoptera: Geometridae), a native Eucalyptus pest in Brazil.

Thyrinteina arnobia (Lepidoptera: Geometridae) is a native American species. Despite its historical importance as an insect pest in Eucalyptus plantations, more information is needed regarding the population diversity, demography, and climatic variables associated with its distribution in different regions of Brazil. We used a phylogeographic approach to infer the genetic diversity, genetic structure, and demographic parameters of T. arnobia. We also conducted an ecological niche modeling (ENM) to predict suitable areas for T. arnobia occurrence in Brazil and other countries worldwide. Although T. arnobia populations have low genetic diversity in Brazil, we identified mitochondrial haplogroups predominating in different Brazilian regions and high ФST and ФCT values in AMOVA, suggesting a low frequency of insect movement among these regions. These results indicate that outbreaks of T. arnobia in Eucalyptus areas in different regions of Brazil are associated with local or regional populations, with no significant contribution from long-distance dispersal from different regions or biomes, suggesting that pest management strategies would be implemented on a regional scale. In Brazil, the demographic and spatial expansion signals of T. arnobia seem to be associated with the history of geographical expansion of Eucalyptus plantations, a new sustainable host for this species. ENM indicated that isothermality and annual rainfall are critical climatic factors for the occurrence of T. arnobia in tropical and subtropical areas in the Americas. ENM also suggested that T. arnobia is a potential pest in Eucalyptus areas in all Brazilian territory and in regions from Africa, Asia, and Oceania.

Antiteuchus tripterus (Fabricius, 1787) (Heteroptera: Pentatomidae): First Record of This Native Stink Bug Damaging the Threatened Araucaria angustifolia in Brazil.

This is the first report of Antiteuchus tripterus (Fabricius, 1787) (Heteroptera: Pentatomidae) damaging Araucaria angustifolia (Bertol.) Kuntze, 1898 (Pinales: Araucariaceae) plants in Brazil. This bug, native to the neotropical region, damaged this plant on fragments of mixed rain forest in Bueno Brandão, Minas Gerais state, Brazil. Araucaria angustifolia, native and with ecological and economic values, was widely used in the lumber market and, therefore, threatened with extinction. Nymphs and adults of A. tripterus were observed in March and April with a population reduction until June 2022. The bioecology and damage caused by A. tripterus on A. angustifolia are not known.

Cordyceps cateniannulata and Cordyceps javanica: first report of pathogenicity to Glycaspis brimblecombei (Hemiptera: Aphalaridae).

Cultivation of species of the genus Eucalyptus is important for the Brazilian economy, with 6.97 million hectares planted. Glycaspis brimblecombei Moore (Hemiptera: Aphalaridae), detected in Brazil in 2003, has dispersed and now damages Eucalyptus crops in all regions of this country. The location and identification of entomopathogenic fungi isolates may increase the options for integrated pest management. The objective of this research was to evaluate the pathogenicity of Cordyceps cateniannulata and Cordyceps javanica isolates to G. brimblecombei. Ten nymphs of G. brimblecombei, with or without lerps, were placed per Eucalyptus leaf cut with one of its edges on hydroretentive gel inside Petri dishes. The fungi isolates were suspended in a solution of Tween 80 (0.1%) at the concentration of 1.0 x 108 conidia mL-1 and sprayed on the G. brimblecombei nymphs. The mortality of this insect was evaluated daily for seven days, and the dead individuals were transferred to humid chambers. The conidia viability of the isolates was greater than 93%. The mortality of G. brimblecombei nymphs, seven days after the application of the fungi, was 100%. This is the first report of the pathogenicity of C. cateniannulata and C. javanica isolates, occurring naturally in the field, to G. brimblecombei.

Detection and estimation of Mastigimas anjosi (Hemiptera: Calophyidae) populations on Cedrela fissilis trees.

Mastigimas anjosi is an important pest of Cedrela fissilis in the southeastern and southern regions of Brazil. The objective of the present study was to investigate the effect of the temperature, relative humidity, rainfall and natural enemies on the flight activity of adults and the movement of M. anjosi nymphs, with two sampling methods, yellow sticky traps and direct collections on the leaves of C. fissilis trees. The sex ratio of this pest was also assessed. The number of M. anjosi individuals was negatively correlated with the minimum and maximum temperatures, with a population peak in late May and early June 2017. The numbers of individuals of this psyllid was positively correlated with the relative humidity and rainfall. Larvae and adults of Cycloneda sanguinea, Hippodamia convergens adults and Atopozelus opsimus nymphs and adults preyed upon M. anjosi adults and nymphs on C. fissilis leaves in the field. Mastigimas anjosi sex ratio was 0.46. Information about sampling methods of M. anjosi and its natural enemies is presented and can contribute to the integrated management of this pest in the field.

Steinernema diaprepesi Nguyen & Duncan (Rhabditida: Steinernematidae), a new entomopathogenic nematode from Brazil.

Entomopathogenic nematodes (EPNs) can control pests due to their mutual association with bacteria. The use of these biological control agents is increasing worldwide due to advances in research about its control efficiency, range of action and mass production. The identification of EPNs adapted to specific environmental and climatic conditions is important for sustainable pest suppression in integrated management (IPM) programs. The objective is to report, for the first time, the occurrence of the Steinernema diaprepesi in Brazil. Steel mesh traps with Galleria mellonella Linnaeus (Lepidoptera: Pyralidae) larvae were buried in red latosol cultivated with Eucalyptus. Infective juveniles (IJs) were isolated from dead larvae and multiplied in healthy ones of this host to confirm its pathogenicity and to start a laboratory population from the strain found in the field. The DNA of the IJs was extracted and amplified using PCR technique with the universal primers D2A and D3B. The detection of S. diaprepesi is the first report of this nematode in Brazil, increasing the knowledge about its distribution in the world and the diversity of EPNs that must be considered as agents of biological pest control in the country.

Identification and genome sequencing of RNA viruses in the eucalyptus snout beetle Gonipterus spp. (Coleoptera: Curculionidae).

The genomes of two putative new RNA viruses (macula-like virus and bunya-like virus) were identified in total RNA extracted from dead eucalyptus snout beetles (Gonipterus spp.) from a laboratory colony. However, only bunya-like virus was detected in field-collected insects. The macula-like virus has a monopartite single-stranded RNA genome that contains three open reading frames (ORFs) encoding an RNA-dependent RNA polymerase (RdRp), a capsid protein (CP), protein with unknown function. The bunya-like virus genome was predicted to consist of two RNA segments: a large segment (L) encoding a single protein (RdRp) and a small segment (S) encoding a putative nucleocapsid protein.

Infection by the microsporidium of Clado Nosema/Vairimorpha in pupal parasitoids.

The sugarcane borer, Diatraea saccharalis is one of the hosts more used for parasitoid pupal multiplication in Brazil. The parasitoids pupal of Trichospilus diatraeae and Palmistichus elaeisis are generalist natural enemies with potential to suppress populations of diverse families of lepidopteran pests. The success in the utilization of these natural enemies in the field is directly related to the capacity of search of the host, this capacity might be affected by the presence of the pathogens. In this context, the aim of this essay was to detect the presence of intracellular parasites of Phylum Microsporidia. These pathogens may cause morphological and behavioral alterations. The presence of infection was verified by microscopy and was confirmed by amplification of region small subunit (SSU) of ribosomal RNA using universal primers for microsporidia of Nosema sp. The purified PCR products were submitted to sequencing, and the sequences that had been obtained were edited and aligned with the sequences in a Genbank database. In this way, it was possible to verify the presence of intracellular parasites in T. diatraeae, P. elaeisis and D. saccharalis pertaining to Clade Nosema/Vairimorpha. However, this is the first one report about detection of the microsporidia in the parasitoids T. diatraeae and P. elaeisis.

Cell-line-dependent crystal morphology and sublocalization of the Thyrinteina arnobia cypovirus polyhedrin expressed from a recombinant baculovirus.

We describe an unexpected feature observed for the heterologous expression of the Thyrinteina arnobia cypovirus polyhedrin from a recombinant baculovirus infection in different insect cell lines. The in cellulo-formed crystals varied in size and shape depending on the cell line. Crystals formed in Trichoplusia ni-derived cells were cubic (0.1-2 µm) and localized in both the nucleus and cytoplasm, whereas those formed in Spodoptera frugiperda-derived cells were ovate and ellipsoidal (0.1-3 µm) and also localized in both the nucleus and cytoplasm. The molecular basis for differences in the morphology, size, and location of cypovirus occlusion bodies is unclear, and cellular proteins might play a role in their formation and location.

Multivariate approach to quantitative analysis of Aphis gossypii Glover (Hemiptera: Aphididae) and their natural enemy populations at different cotton spacings.

The relationship between pests and natural enemies using multivariate analysis on cotton in different spacing has not been documented yet. Using multivariate approaches is possible to optimize strategies to control Aphis gossypii at different crop spacings because the possibility of a better use of the aphid sampling strategies as well as the conservation and release of its natural enemies. The aims of the study were (i) to characterize the temporal abundance data of aphids and its natural enemies using principal components, (ii) to analyze the degree of correlation between the insects and between groups of variables (pests and natural enemies), (iii) to identify the main natural enemies responsible for regulating A. gossypii populations, and (iv) to investigate the similarities in arthropod occurrence patterns at different spacings of cotton crops over two seasons. High correlations in the occurrence of Scymnus rubicundus with aphids are shown through principal component analysis and through the important role the species plays in canonical correlation analysis. Clustering the presence of apterous aphids matches the pattern verified for Chrysoperla externa at the three different spacings between rows. Our results indicate that S. rubicundus is the main candidate to regulate the aphid populations in all spacings studied.

The exotic wasp Megastigmus transvaalensis (Hymenoptera: Torymidae): first record and damage on the Brazilian peppertree, Schinus terebinthifolius drupes, in São Paulo, Brazil.

This paper records the first report of Megastigmus transvaalensis Hussey (Hymenoptera: Torymidae) in Brazilian peppertree, Schinus terebinthifolius Raddi (Anacardiaceae) drupes in Sorocaba, state of São Paulo, Brazil. This wasp is an invasive species and was found damaging S. terebinthifolius drupes in urban areas (35.0 ± 15.8%), natural forests (21.5 ± 10.2%) and restoration areas (15.8 ± 8.4%). The bio-ecology and damage caused by M. transvaalensis in the S. terebinthifolius drupes warrants further study focused upon the management of this phytophagous wasp. Megastigmus transvaalensis has a potential to be disseminated throughout Brazil and is posing a threat to the natural regeneration of S. terebinthifolius in the native forests and restoration areas and ecological regions of this country.

Does Diatomaceous Earth Control Leaf-Cutter Ants (Hymenoptera: Formicidae) in the Eucalyptus Plantations?

Genus Atta includes some of the most important Formicidae leaf cutter ants which cause extensive damage to the eucalyptus plantations. Atta sexdens rubropilosa Forel, one of the chief pests in Brazilian reforestation, can restrict and reduce forest productivity by its intense and constant leaf-cutting activities on plants at all stages. Therefore, the demand for new products to control A. sexdens rubropilosa indicates the study of the utilization of the dry powder formulation of diatomaceous earth (DE) against this pest in the eucalyptus cultivars. The study was conducted using 120 colonies of A. sexdens rubropilosa in Eucalyptus grandis Hill ex. Maiden x Eucalyptus urophylla Blake (Myrtaceae) (urograndis) stand. The randomized block experimental design was used with six treatments (1, 10, 25, and 50 g/m2 of DE, 6.0 g/m2 sulfluramid bait per square meter of loose soil, and the control) with five replications, each with four colonies of this ant. Diatomaceous earth was applied to the active A. sexdens rubropilosa ant holes, and the sulfluramid bait was applied in bulk in a localized manner. The control efficacy of A. sexdens rubropilosa with DE was low, showing values similar to that of the control, and, for this reason, it cannot be used to control this ant. The bait with sulfluramid showed higher efficacy than those of the other treatments.

Eucalyptus ESTs involved in the production of 9-cis epoxycarotenoid dioxygenase, a regulatory enzyme of abscisic acid production

Abscisic acid (ABA) regulates stress responses in plants, and genomic tools can help us to understand the mechanisms involved in that process. FAPESP, a Brazilian research foundation, in association with four private forestry companies, has established the FORESTs database (https://forests.esalq.usp.br). A search was carried out in the Eucalyptus expressed sequence tag database to find ESTs involved with 9-cis epoxycarotenoid dioxygenase (NCED), the regulatory enzyme for ABA biosynthesis, using the basic local BLAST alignment tool. We found four clusters (EGEZLV2206B11.g, EGJMWD2252H08.g, EGBFRT3107F10.g, and EGEQFB1200H10.g), which represent similar sequences of the gene that produces NCED. Data showed that the EGBFRT3107F10.g cluster was similar to the maize (Zea mays) NCED enzyme, while EGEZLV2206B11.g and EGJMWD2252H08.g clusters were similar to the avocado (Persea americana) NCED enzyme. All Eucalyptus clusters were expressed in several tissues, especially in flower buds, where ABA has a special participation during the floral development process

Eucalyptus ESTs related to genes for oxidative stress.

Oxidative stress generating active oxygen species has been proved to be one of the underlying agents causing tissue injury after the exposure of Eucalyptus (Eucalyptus spp.) plants to a wide variety of stress conditions. The objective of this study was to perform data mining to identify favorable genes and alleles associated with the enzyme systems superoxide dismutase, catalase, peroxidases, and glutathione S-transferase that are related to tolerance for environmental stresses and damage caused by pests, diseases, herbicides, and by weeds themselves. This was undertaken by using the eucalyptus expressed-sequence database (https//forests.esalq.usp.br). The alignment results between amino acid and nucleotide sequences indicated that the studied enzymes were adequately represented in the ESTs database of the FORESTs project.

Comportamento de chamamento de Thyrinteina arnobia (Stoll) (Lepidoptera: Geometridae) em Psidium guajava, Eucalyptus grandis e em dieta artificial / Calling behavior of Thyrinteina arnobia (Stoll) (Lepidoptera: Geometridae) reared on Psidium guajava and Eucalyptus grandis host-plant leaves and on artificial diet

This work was carried out to determine and compare the effects of three diets (Psidium guajava and Eucalyptus grandis host-plant leaves and artificial diet) on the calling behavior and on thetemporal pattern of calling behavior of Thyrinteina arnobia (Stoll). All activities of virgin females during six scotophases were observed in the laboratory at 5min. intervals until the females stoppedcalling in the following photophase, at 22 ± 1oC, 70 ± 5% RH and 10h scotophase. The diets affected the calling behavior of T. arnobia. Two positions of calling were observed. Calling of female virgins started in the first hour immediately after emergence. The calling pattern was characteristic of the continuous pattern. The type of diet affected the mean onset of calling time (pre-calling) and the total time calling ofT. arnobia. Older females called earlier than younger after the onset of scotophase. The diets affected the color of pheromone gland.

Este estudo teve como objetivos determinar e comparar o efeito de três dietas: Psidium guajava, Eucalyptus grandis e dieta artificial no comportamento de chamamento e no padrão temporal do comportamento de chamamento de fêmeas virgens de Thyrinteina arnobia (Stoll). Foram analisados os parâmetros: tempo médio para o início do chamamento, número médio de chamamento, tempo médiode cada chamamento e tempo médio total de chamamento. Os bioensaios relacionados ao comportamento de chamamento de fêmeas virgens foram realizados durante seis escotofases consecutivas e as observações tomadas a cada 5 min., a 22 ± 1oC, 70 ± 5% de UR e 10h de escotofase. As fêmeas,independente da dieta analisada, apresentaram duas posições diferentes de chamamento. A maioria das fêmeas virgens iniciou o chamamento na 1a hora da 1a escotofase. O padrão de chamamento da fêmea individualizada foi característico de um padrão contínuo. O tipo de dieta oferecida na fase larvalinfluenciou o início do comportamento de chamamento (pré-chamamento) e o tempo médio total de chamamento. O tipo de dieta também alterou a coloração da glândula de feromônio.