Julio C. Guerreiro

Does diatomaceous earth control leaf-cutter ants (Hymenoptera: Formicidae) in the Eucalyptus plantations?

ABSTRACT 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.

Biological control of Glycaspis brimblecombei (Hemiptera: Aphalaridae) in eucalyptus plantations

The genus Eucalyptus, native to Australia, is the host of psylloid insects such as the red gum lerp psyllid Glycaspis brimblecombei, a major Eucalyptus pest introduced into Brazil among other countries. The encyrtid Psyllaephagus bliteus is a primary parasitoid used in the biological control of G. brimblecombei. This study aimed to determine the parasitism of G. brimblecombei by P. bliteus released in eucalyptus plantations. Investigations were carried out in a 19-ha eucalyptus plantation comprised of 9-year-old Eucalyptus camaldulensis (Myrtaceae) in the municipality of Luiz Antônio, São Paulo State, Brazil. Twenty P. bliteus pairs were released at five points in the study area between May and September 2006 and 2007 approximately every 20 days. For evaluation of parasitism, ten leaves per twig were randomly selected and unparasitized nymphs of G. brimblecombei, mummies (parasitized nymphs of G. brimblecombei) and empty mummies (after emergence of P. bliteus adults) were counted on their abaxial and adaxial parts before and after each release of P. bliteus. The parasitism rates of G. brimblecombei in 2006 and 2007 were 0.21–5.92% and 0.28–7.03% in the control; these values rose to 28.28–78.57% and 30.32–79.34%, respectively, in areas involved in parasitoid release. Parasitism levels of G. brimblecombei nymphs in areas with P. bliteus release were affected by the environmental temperature, which is discussed as a potential limitation to the establishment of this parasitoid and to its effectiveness as a biological control agent.

Susceptibility of Eucalyptus spp. (Myrtales: Myrtaceae) and Clones to Leptocybe invasa (Hymenoptera: Eulophidae) in Paraná, Brazil

Summary ‘Grancam COP 1277’ had the highest percentage of leaves and petioles attacked by L. invasa, whereas ‘Urograndis (seminal)’, ‘Urocam VM1’ and E. grandis had lower and statistically similar values. The attack by the wasp on C. citriodora was relatively minor compared with the above susceptible lines. Statistical differences were observed among similar proportions of attack between the oviposition preference on the 3 strata, leaves, and petioles of the assessed trees.

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.

The native psyllid Mastigimas anjosi (Hemiptera: Calophyidae): first record and abundance on pink cedar, Cedrela fissilis (Meliaceae), trees in São Paulo, Brazil

Summary The objective of this study was to identify and report on the occurrence of Psylloidea damaging pink cedar, Cedrela fissilis Vell. (Meliaceae), plants in the municipality of Sorocaba, in the southern region of São Paulo State, Brazil. Psyllids were collected on C. fissilis plants, and sent to authorities for identification. Psyllids damaging C. fissilis plants in urban areas and fragments of semideciduous seasonal forest were identified as Mastigimas anjosi Burckhardt, Queiroz D., Queiroz E., Andrade, Zanol Rezende & Kotrba (Hemiptera: Psylloidea: Calophyidae), which is native to Brazil. Cedrela fissilis also is endemic to Brazil, and has high ecological and economic value. It is harvested for timber production and is on the endangered species list. This is the first report of M. anjosi damaging C. fissilis plants in São Paulo State, Brazil and the importance of this plant for conservation and ecological restoration areas in Brazil justifies research to develop management programs for this psyllid.

First Record of the Wood-Borer Hylettus seniculus (Coleoptera: Cerambycidae) in Pinus caribaea var. Hondrurensis Plantations in Brazil

Summary Here we report for the first time the occurrence of Hylettus seniculus Germar 1824 (Coleoptera: Cerambycidae) boring Pinus caribaea var. hondurensis Morelet (Pinaceae) trunks. Damage by this insect were evaluated from August to Dec 2008 and 2009 by cutting a tree per month from 5 groups of trap trees (5 plants per group) stressed with systemic herbicide. The damage by H. seniculus on trap trees P. caribaea var. hondurensis indicates that prolonged storage of pine logs in the field should be avoided.