Entomologia

Losses in root and planting material production caused by different pests as well as their biological control are evaluated. Studies of pests damaging dried cassava in storage were initiated. Biological aspects and form of attack of the following pests are described: stemborers (Lagochirus rogersi, L. araneiformis, Chilomina clarkei), shoot flies (Silba pendula), nymphs and adults of Cyrtomenus bergi, and lacebugs (Vatiga manihotae and V. illudens). Zelus nugax (Reduviidae) was identified as a major predator of V. manihotae. The presence of whiteflies (Aleurotrachelus socialis) and sooty mold reduces root yield. The varietal preference for oviposition by Erinnyis ello was determined as well as the effect of simulated damage on yield, starch content, and cooking quality of cassava. Five major enemies of the cassava mealybug Phenacoccus herreni were identified: Ocyptamus, Cleothera, Anagyrus, Sympherobius, and Chrysopa. An unidentified species of mite belonging to the family Eriophyidae found attacking cassava leaves is parasitized by the fungus Hirsuthella tompsonii. Fifteen insect species were found feeding on stored cassava; among these,Araecerus fasciculatus and Lasioderma serricorne are the most frequently found pests. Both species are parasitized by the hymenopteran Anisopteromalus sp. (CIAT

Spodoptera frugiperda (Lepidoptera: Noctuidae) updated host plants and new records.

Conteúdo do volume 2: Ácaros; Biologia, fisiologia, morfologia; Controle biológico com bactérias entomopatogênicas; Controle biológico com fungos entomopatológicos; Controle biológico com nematoides; Controle biológico com parasitoides; Controle biológico com predadores; Ecologia e biodiversidade; Educação e etnoentomologia; Entomologia florestal; Entomologia Forense; Entomologia médica e veterinária; Entomologia molecular; Manejo integrado de pragas; Organismos geneticamente modificados; Plantas inseticidas; Polinização; Pragas quarentenárias e invasivas; Resistência de insetos a táticas de controle; Resistência de plantas a insetos; Semioquímicos e comportamento; Sistemática e taxonomia; Tecnologia de aplicação; Controle biológico com vírus entomopatogênicos; Controle químico

Comparison of biological and reproductive parameters between Helicoverpa zea and Helicoverpa arm¡gera in Argentina.

Conteúdo do volume 2: Ácaros; Biologia, fisiologia, morfologia; Controle biológico com bactérias entomopatogênicas; Controle biológico com fungos entomopatológicos; Controle biológico com nematoides; Controle biológico com parasitoides; Controle biológico com predadores; Ecologia e biodiversidade; Educação e etnoentomologia; Entomologia florestal; Entomologia Forense; Entomologia médica e veterinária; Entomologia molecular; Manejo integrado de pragas; Organismos geneticamente modificados; Plantas inseticidas; Polinização; Pragas quarentenárias e invasivas; Resistência de insetos a táticas de controle; Resistência de plantas a insetos; Semioquímicos e comportamento; Sistemática e taxonomia; Tecnologia de aplicação; Controle biológico com vírus entomopatogênicos; Controle químico

Foraging behavior of fire ant Solenopsis saevissima (Smith) (Hymenoptera: Formicidae) in Felis catus Linnaeus (Carnivora: Felidae) carcass

Solenopsis saevissima fire ants were found foraging in a Felis catus carcass over tissues an secretions present in holes and mucosa. The ants built a dirt-made physical structure around the carcass, which prevented necrophagous flies from laying eggs or larvae in the body. These observations are relevant to increasing knowledge on the role of this ant genus in the decaying process of other animal corpses, including humans

Addenda and omissions to the catalogue and checklist of the Cerambycidae and Disteniidae (Coleoptera) of the Western hemisphere

The Catalogue (Monne, 1993-1994) and Checklist (Monne and Giesbert, 1995) of the Cerambycidae and Disteniidae of the Western Hemisphere represents a necessary, and valuable tool since recompilation of Blackwelder (1946) was made. Species with references (omissions), and without them (new records) are given for some countries

Female-induced increase of host-plant volatiles enhance specific attraction of aphid male Dysaphis plantaginea (Homoptera: Aphididae) to the sex pheromone

All aphid species studied so far share the same sex pheromone components, nepetalactol and nepetalactone. Variation by different enantiomers and blends of the two components released by different aphid species are limited and can only partially explain species-specific attraction of males to females. While some host-plant odours are known to enhance specific attraction of aphid species, herbivore-induced plant volatiles that synergise attractiveness to the sex pheromone are unknown. Here, we demonstrate that for the host-alternating rosy apple aphid (Dysaphis plantaginea (Passerini)) specificity of attraction of males to females is triggered by female-induced tree odours in combination with a 1:8 ratio of (4aS,7S,7aR)-nepetalactone and (1R,4aS,7S,7aR)-nepetalactol. Female aphid infestation induces increased release of four esters (hexyl butyrate, (E)-2-hexenyl butyrate, (Z)-3-hexenyl 3-methylbutyrate and hexyl 2-methylbutyrate) from apple leaves. Two different combinations of three esters applied in a 1:1:1 ratio increase the number of male D. plantaginea and decrease the number of other aphid species caught in water traps in the presence of the pheromone components. The ester blend alone was not attractive. Combination of the pheromone blend with each single ester was not increasing attraction of male D. plantaginea. The demonstration that sexual aphid species use herbivore-induced plant volatiles as a species-specific attractant for mate finding adds a new dimension to our understanding of insect species using or manipulating chemical cues of host plants for orientatio

Suscetibilidade de Gyropsylla spegazziniana (Lizer & Trelles) (Hemiptera: Psyllidae) a Beauveria bassiana (Bals.) Vuill

Gyropsylla spegazziniana is one of the most prominent pest insects of yerba mate culture in all production regions in Brazil, Argentina and Paraguay. Natural enemies have been recorded on G. spegazziniana nymphs and adults, including the Zoophthora radicans entomopathogenic fungus. Since there are no reports of Beauveria bassiana, the aim of this study was to register its pathogenicity with respect to this insect in a laboratory setting. Yerba mate branches were kept in glass flasks with water and we infested each leaf with 20 newly-emerged nymphs. We prepared three replicates per treatment. We sprayed conidia suspensions (1 × 109 conidia/mL) onto the branches, which we transferred to cages and kept in an acclimatized room (26 ± 1°C, 70 ± 10% of relative humidity (R.H.) with a photophase of 14 hours). We evaluated insect mortality daily, and after five days we observed a high level of pathogenicity due to the presence of the fungus, that could be visually observed on the cadaver. The total mortality varied from 25 to 70% (respectively for Unioeste 4 and CG 716) and the confirmed mortality was 30% for Unioeste 52, revealing the fungus’ potential. However, more studies are necessary in order to evaluate the strains of this fungus, as well as other species.Gyropsylla spegazziniana é uma das principais pragas da cultura de erva-mate em todas as regiões produtoras do Brasil, da Argentina e do Paraguai. Inimigos naturais têm sido registrados sobre ninfas e adultos de G. spegazziniana, incluindo o fungo entomopatogênico Zoophthora radicans. Como não há relatos sobre Beauveria bassiana, o objetivo deste estudo foi registrar sua patogenicidade sobre esse inseto em condições de laboratório. Ramos de erva-mate foram infestados com insetos e mantidos em frascos de vidro com água. Cada um dos ramos tinha cerca de 20 ninfas recém-emergidas/ folha, sendo preparadas 3 repetições/tratamento. As suspensões dos isolados do fungo (1 × 109 conídios/mL) foram pulverizadas sobre os ramos, que foram transferidos para gaiolas e mantidos em sala climatizada (26 ± 1°C, 70 ± 10% de Umidade Relativa (U.R.) e 14 horas de fotofase). Diariamente, realizou-se a avaliação da mortalidade do inseto, observando-se, após cinco dias da aplicação, alto nível de patogenicidade devido à presença do fungo, constatada visualmente sobre os cadáveres. A mortalidade total variou entre 25 e 70% (respectivamente para Unioeste 4 e CG 716) e a mortalidade confirmada foi de 30% para o isolado Unioeste 52, revelando o potencial do fungo. No entanto, mais estudos são necessários para avaliar novos isolados do fungo, bem como outras espécies.Fil: Alves, Luis Francisco. Universidade Estadual do Oeste do Paraná; BrasilFil: Formentini, Marina Andresa. Universidade Estadual do Oeste do Paraná; BrasilFil: Fanti, André Luis. Universidade Estadual do Oeste do Paraná; BrasilFil: Schapovaloff, María Elena. Universidad Nacional de La Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Barzotto, Ionete. Universidade Estadual do Oeste do Paraná; Brasi

Hoverflies in organic apple orchards in north-western Italy

A list is given of hoverflies collected by means of Malaise and white sticky traps in two organic apple orchards in north-western Italy. The total number of collected species was 17 and it was compared with literature, in order to discuss differences due to sampling methods. The predominant species collected were Sphaerophoria scripta (L.) (73% of the total sample) and Eupeodes corollae (F.) (14%). The trend of adult captures of this species is drawn and discussed. Data on wild plant species in the orchards are also given

Obtenção de isolados de nematóides entomopatogênicos visando o controle de corós-praga do trigo.

Área: Entomologia