Showing papers in "Neotropical Entomology in 2003"

Efeito de pós de origem vegetal sobre Acanthoscelides obtectus (Say) (Coleoptera: Bruchidae) em feijão armazenado

Abstract: Determinou-se a bioatividade dos pos de 18 especies vegetais em relacao a Acanthoscelides obtectus (Say), avaliando-se o efeito desses materiais no comportamento e sobrevivencia do inseto Em todos os experimentos foi utilizada a proporcao 0,3 g de po de cada especie vegetal para 10 g de feijao Nos testes de repelencia, foram utilizadas arenas constituidas por cinco recipientes plasticos circulares, sendo a caixa central interligada simetricamente as demais por tubos plasticos, em diagonal onde os adultos podiam escolher amostras de feijao tratadas ou nao tratadas (testemunhas) Apos 24h, contou-se o numero de insetos por recipiente Para avaliacao da atividade inseticida, adultos recem-emergidos foram liberados em caixas plasticas contendo graos de feijao tratados com o po de cada planta, usando-se graos nao tratados como testemunha No quinto dia, foi calculado o numero de insetos mortos e o numero de ovos (total e ferteis) O tratamento mais eficiente foi o po da parte aerea de erva-de-santa-maria (Chenopodium ambrosioides, p2) que provocou repelencia, mortalidade total dos adultos e nenhuma oviposicao, vindo a seguir as cascas de Citrus sinensis (laranja 'Pera') e folhas de Lafoensia glyptocarpa (mirindiba) Folhas de Coriandrum sativum (coentro) nao foram repelentes, porem provocaram mortalidade total dos adultos e, consequentemente, nenhuma oviposicao Tambem provocaram repelencia: a parte aerea de C ambrosioides (p1); folhas de Eucalyptus citriodora (eucalipto-cheiroso), Mentha pulegium (poejo), Ocimum basilicum (alfavaca), O minimum (manjericao) e Ruta graveolens (arruda); cascas de Citrus reticulata (laranja 'Murcote') e frutos de Melia azedarach (cinamomo) e L glyptocarpa

Effect of sodium silicate application on the resistance of wheat plants to the green-aphids Schizaphis graminum (Rond.) (Hemiptera: Aphididae)

Abstract: O pulgao-verde Schizaphis graminum (Rond.) e importante praga do trigo, causando danos as plantas em todos os estagios fenologicos da cultura. Este trabalho teve como objetivo avaliar o efeito da aplicacao de silicio na resistencia de plantas de trigo a esta praga. Foram conduzidos ensaios em casa-de-vegetacao e em laboratorio. O experimento em casa de vegetacao foi conduzido em delineamento experimental completamente casualizado com dois tratamentos, que consistiram na aplicacao de silicio e testemunha (sem aplicacao), e dez repeticoes, sem controle ambiental. Os bioensaios em laboratorio foram realizados em câmara climatizada, a temperatura de 25 ± 1°C, umidade relativa de 70 ± 10% e fotofase de 12h, com delineamento experimental de blocos ao acaso, em esquema de parcelas subdivididas. O silicio, na forma de solucao de silicato de sodio a 0,4% de SiO2 foi aplicado na dose de 50 ml/vaso, por seis vezes, em intervalos de cinco dias, sendo a primeira realizada cinco dias apos a emergencia das plantas de trigo. A partir do 35o dia apos a emergencia das plantas foram realizadas as seguintes avaliacoes: a) preferencia em teste com chance de escolha em laboratorio; b) preferencia em teste com chance de escolha em casa-de-vegetacao; e c) reproducao e desenvolvimento do pulgao-verde em laboratorio. A aplicacao de silicato de sodio reduziu a preferencia, a longevidade e a producao de ninfas do pulgao-verde S. graminum, conferindo, portanto, resistencia as plantas de trigo a este inseto-praga.

The impact of fungicides on Nomuraea rileyi (Farlow) Samson epizootics and on populations of Anticarsia gemmatalis Hübner (Lepidoptera: Noctuidae), on soybean

Abstract: The fungus Nomuraea rileyi (Farlow) Samson is one of the most important natural enemies of soybean caterpillars, mainly under humid weather conditions. Outbreaks of the fungus Microsphaera diffusa Cooke & Peck have demanded fungicide applications on soybeans, which could result in outbreaks of noctuid populations by reduction of the natural inocula of N. rileyi. The recommended fungicides have shown to be detrimental to beneficial fungi, reducing infection, delaying epizootics, and resulting in increased host population densities. In laboratory assays, benomyl, difenoconazole, sulphur and carbendazim affected conidial germination of N. rileyi, being the latter less deleterious. To assess the impact of fungicides used to control M. diffusa, on N. rileyi, two tests were carried on, spraying difenoconazole (75 g a.i./ha) and benomyl (262.5 g a.i./ha) on soybean plots. In the 1997/98 trial, fungicide was sprayed once on soybean plants at R1-R2 developmental stages. In the 1998/99 test, two applications were made, when plants were at V5 and V7 developmental stages, respectively. The number of VBC larvae was significantly higher in the fungicide treated plots than in the control plots. In the 1997/98 test, benomyl treated plots resulted in higher populations of VBC than in the control or in the difenoconazole plots. In the 1998/99 test, VBC population was higher from 7 to 12 days after the first application, and remained high until 19 days after the second application. In general, fungicide treatments delayed the begining of N. rileyi epizootics from 2 to 14 days.

Plantas visitadas por Centris spp. (Hymenoptera: Apidae) na Caatinga para obtenção de recursos florais

Abstract: A revision of flower visitation records by bees of the genus Centris in the Caatinga, the xerophylous vegetation predominant in the semi-arid Northeastern Brazil, is presented. This revision includes, besides literature data, results from six annual surveys of the bee fauna and visited flowers, undertaken in limited areas of the States of Paraiba, Bahia and Rio Grande do Norte, Brazil. A total of 21 species of Centris were registered in these surveys, the highest species richness was observed in Castro Alves and Itatim (Bahia), 12 and 10 species, respectively. The higher species richness probably results from the presence of elements in adjacent biomas, since these two places are close to the eastern limit of the Caatinga. A total of 69 species of visited plants were registered. Caesalpinia pyramidalis (Caesalpiniaceae) and Melochia tomentosa (Sterculiaceae) are important nectar sources, as indicated by the higher number of Centris visitors' and by the number of areas where they occurred. Species of Chamaecrista, Senna (Caesalpiniaceae), and Solanum (Solanaceae) seem to be important pollen sources. Chamaecrista nictitans and C. pascuorum are registered for the first time as pollen sources for Centris hyptidis. The oil sources registered in the Caatinga for Centris bees belong to the families Malpighiaceae and Scrophulariaceae. Among the more abundant species of Centris, those not restricted to the Caatinga region (C. fuscata, C. aenea, C. tarsata and C. trigonoides) present a high similarity in the spectrum of visited plants. C. hyptidis, an endemic species, has a somewhat distinct niche.

Effect of prey density on the functional and numerical responses of two species of predaceous mites (Acari: Phytoseiidae)

Abstract: Phytoseiidae mites are the most important and studied natural enemies of pest mites. A question frequently raised is whether phytoseiid may reduce high densities of phytophagous mites. Studies of functional and numerical responses may help to answer this question. The aim of this work was to evaluate the potential predation success of Iphiseiodes zuluagai Denmark and Muma and Euseius alatus DeLeon (Acari: Phytoseiidae) on Brevipalpus phoenicis (Geijskes) (Acari: Tenuipalpidae), vector of the citrus leprosis and the coffee ringspot viruses. Bioassays were performed in the laboratory. Adult females of each predator were isolated in arenas made with citrus leaves (3-cm diameter). Immature stages of B. phoenicis were offered as prey, at the following numbers/arena: 1, 2, 5, 10, 20, 30 and 35 (seven replicates), 45 (four replicates), 55 (three replicates) and 70, 100, 125, 200 and 300 (two replicates). The number of killed prey and of eggs laid by the predators was evaluated every 24h, during eight days. Killed prey was replaced daily by new prey. For both predatory mites, a positive and highly significant correlation was found between the numbers of prey offered and killed. The average daily oviposition rate also increased with the number of killed prey. At the lower densities, E. alatus killed and ate more B. phoenicis than I. zuluagai. The opposite was observed at the highest densities. It is possible that E. alatus can reduce B. phoenicis population even at low prey densities, and I. zuluagai can do the same also at high densities. The fact that E. alatus requires less prey than I. zuluagai suggests that its survivorship may be higher than that of I. zuluagai at low prey densities.

Distribuição espacial de Alabama argillacea (Hübner) (Lepidoptera: Noctuidae) em algodoeiro

Abstract: The knowledge of the dispersion pattern of the pests on a crop is fundamental for establishing an appropriated sequential sampling method. Also it permits the correct utilization of control strategies and optimization of sampling techniques. The objective of this research was to determine the spatial distribution of larvae of Alabama argillacea (Hubner) on cotton crop, CNPA ITA-90 cultivar. During the 1998/99 growing season a sampling system was applied in three experimental areas located at Itamarati Sul S.A. farm in the region of Ponta Pora, estate of Mato Grosso do Sul, Brazil. The areas measured 1 ha and contained 100 plots with 100 m2. In a weekly basis the number of small, medium and large larvae were counted on five plants per plot. The aggregation indexes (variance/mean ratio and Morisita index), the chi-square test and the adjust of observed and expected values to theoretical distributions of frequencies (Poisson, positive binomial and negative binomial) showed that all stages of cotton leafworm larvae were distributed according to the contagious model, fitting the Negative Binomial Distribution during the whole period of infestation.

Flora visitada pelas abelhas eussociais (Hymenoptera, Apidae) na Serra da Capivara, em caatinga do Sul do Piauí

Abstract: Estudou-se a flora explorada por Apis mellifera L. (abelhas africanizadas) e meliponineos, em vegetacao de caatinga, no Parque Nacional da Serra da Capivara, PI. Durante um ano foram feitas amostragens mensais em dois locais, utilizando-se redes entomologicas para a coleta das abelhas eussociais em visita as plantas. Coletaram-se 69 especies de angiopermas de 28 familias nos dois locais amostrados. Leguminosae foi a familia com maior numero de especies florais e de maior visitacao pelas abelhas eussociais, como ocorreu com outras localidades de caatinga, mas ha poucas especies melitofilas em comum. As plantas coletadas foram visitadas por 12 especies de meliponineos e, ou pelas abelhas africanizadas. A. mellifera visitou 32 especies florais e os meliponineos 58 especies, destes destacou-se Trigona spinipes Fabr. com maior espectro de plantas visitadas. O comportamento oportunista foi aparente em A. mellifera, mas nao foi observado em todas as especies de meliponineos coletadas. A fenologia da flora e da fauna de abelhas foi similar a relatada em outros estudos regionais de mesma formacao floristica: abundância e heterogeneidade floral durante a estacao chuvosa, favorecendo o forrageamento das abelhas, e escassez de recursos florais durante a seca, quando a ocorrencia das abelhas se reduz.

Bacillus thuringiensis survey in Brazil: geographical distribution and insecticidal activity against Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae)

Abstract: A total of 3408 strains of Bacillus thuringiensis were collected from 1448 soil samples in 10 Brazilian states, four different geographical regions, covering 96 counties. These strains were evaluated against Spodoptera frugiperda (J.E. Smith) larvae. Only 62% killed between 81% and 100% and 1758 caused no mortality. Highest proportion of efficient strains (larval mortality above 75%) was found from the total isolated per region in the South Region (16.6%), followed by Western Central (3.1%), Southeast (1.1%) and Northeast Region (0.4%).

Análise faunística de espécies de moscas-das-frutas (Diptera: Tephritidae) na região Oeste de Santa Catarina

Abstract: Visando caracterizar os ecossistemas de arvores frutiferas da Regiao Oeste de Santa Catarina em relacao as especies de Tephritidae, realizou-se uma analise faunistica em doze pomares de quatro municipios (Chapeco, Cunha Pora, Sao Carlos e Xanxere). O levantamento foi feito entre outubro de 1998 e setembro de 2000, utilizando armadilhas tipo McPhail com glicose invertida a 10%. Para a caracterizacao dos municipios foram medidos os indices de abundância, constância, dominância e frequencia. Foram coletados 8.393 especimes de moscas-das-frutas, pertencentes a 20 especies e sete generos. No municipio de Chapeco foram amostradas 17 especies de moscas-das-frutas, correspondendo ao indice de diversidade de 2,0, seguido por Cunha Pora, com dez especies e indice de 1,5. Em Xanxere o indice foi de 1,1 para oito especies. O menor indice foi obtido em Sao Carlos (0,9), para sete especies. Ceratitis capitata (Wied.) foi acidental na quase totalidade dos pomares onde ocorreu, com excecao apenas de um pomar de laranjeira de Sao Carlos, onde foi acessoria. Anastrepha fraterculus (Wied.) foi a especie predominante nos quatro municipios.

Discovery and development of biological agents to control crop pests

Abstract: Thousands of potential microbial biocontrol agents have been isolated from agricultural fields and crops during research over the last 80 years, yet only a few are in commercial use. Recently, public health and safety concerns about the environmental impact of chemical pesticides have led to consideration of biological control as a natural approach to maintaining crop health. Despite environmental incentives and strong research efforts, commercialization of biocontrol agents has been slow to evolve. The momentum of the chemical industry is difficult to shift, and fermentation processes tend to be more expensive to operate than synthetic chemical processes.Yet there is a demand for biological control products, especially in agricultural niche markets, where there is no chemical competitor. However, given this market demand, the fundamental methods of economical large-scale production and application of biological control agents are lacking. Many aspects of biocontrol agent production and development represent untrodden territory in the progression of industrial fermentation technology beyond its well-established food and pharmaceuticals niche. Distinguishing them from traditional fermentation products, biocontrol agents must not only be produced in high yield but must also meet the following quality criteria: high (near 100%) retention of cell viability with maintenance of crop compatibility and consistent bioefficacy during several months of storage. Research examples will be reviewed to illustrate the challenges and strategies of developing processes to manufacture and deliver biological agents for insect, weed, and plant disease control.

Bioatividade de extratos aquosos de Trichilia spp. sobre Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) em milho

Abstract: Spodoptera frugiperda (J.E. Smith) e atualmente a principal praga da cultura do milho. Seu controle demanda elevado numero de aplicacoes de inseticidas sinteticos, o que agrava o problema de resistencia da praga a esses produtos e contaminacao do ambiente. Desta forma, o uso de plantas inseticidas apresenta-se como uma alternativa para o controle do inseto. Neste trabalho, foi avaliada a eficiencia de extratos aquosos de ramos e folhas de seis especies de Trichilia (T. casaretti, T. catigua, T. clausseni, T. elegans, T. pallens e T. pallida), em comparacao com a do extrato aquoso de sementes de Azadirachta indica (nim) sobre a lagarta S. frugiperda em condicoes de laboratorio. Folhas de milho foram imersas nos extratos e, apos evaporado o excesso de agua, fornecidas a lagartas de primeiro instar, avaliando-se apos cinco dias a sobrevivencia e peso larval. Para as seis especies testadas, pelo menos uma das estruturas (ramos ou folhas) afetou o desenvolvimento do inseto. O extrato de folhas de T. pallens causou mortalidade larval semelhante a causada pelo extrato de nim; os extratos de ramos de T. pallens, e de ramos e folhas de T. pallida, embora menos eficientes, tambem reduziram a sobrevivencia e o peso larval de S. frugiperda.

Natural enemies of Bemisia tabaci (Gennadius) B biotype and Trialeurodes vaporariorum (Westwood) (Hemiptera: Aleyrodidae) in Brasília, Brazil

Abstract: A survey was conducted in Brasilia, DF, from January 1999 to March 2001, on tobacco, cotton, tomato, cabbage, soybean, bean, melon, eggplant and the weed Emilia sonchifolia DC, to collect natural enemies of the whiteflies Bemisia tabaci (Gennadius) and Trialeurodes vaporariorum (Westwood). Fourteen predators, twelve parasitoids and two hyperparasitoids were collected. Among the parasitoids, Encarsia inaron (Walker) is recorded for the first time in South America, and E. basicincta Gahan is a new record for Brazil. E. aleurothrixi Evans & Polaszek is recorded for the first time parasitizing B. tabaci. The lady beetles Nephaspis hydra Gordon and Delphastus davidsoni Gordon are registered for the first time preying on B. tabaci.

Reproductive phenology of the Mexican fruit fly, Anastrepha ludens (Loew) (Diptera: Tephritidae) in the Sierra Madre Oriental, Northern Mexico

Abstract: In its native habitat in northern Mexico, Anastrepha ludens (Loew) is normally bivoltine although a third generation is achieved in some years. The flies overwinter mainly in the puparial stage, emerging in January-February. These flies oviposit in the spring crop of a wild citrus, Sargentia greggii (S. Wats.). The primary population peak follows in late spring to early summer (in exceptional years, separate peaks in spring and summer). Dissection of the females demonstrated that most of the flies in the spring peak are reproductively immature, indicating emergence of new adults. Activity subsides in late summer, or at least, few flies can be trapped at this time. Then in the fall there is a resurgence of adult activity. However, in contrast to the spring peak, dissection revealed that the great majority of the fall adult females are already gravid, indicating that they are carry-overs from the early summer population, rather than new recruits. The fall adults oviposit in October-November, producing the overwintering population that will emerge as adults in January-February.

Life-history of the guava weevil, Conotrachelus psidii Marshall (Coleoptera: Curculionidae), under laboratory conditions

Abstract: The guava weevil, Conotrachelus psidii Marshall, is a severe pest of guava fruits in Brazil. The mated females lay eggs in small unripe fruits. As the fruits develop, so do the larvae. Mature larvae abandon the ripe fruits and pupate underground. Larval feeding causes extensive damage to the fruit. We conducted this study to understand the weevil biology under laboratory conditions. Weevil-infested ripe guava were collected in orchards and placed inside cages with moist sand. After emergence, the adults were individually placed in acrylic boxes with food and water. Recently emerged adults were also placed inside plastic boxes for mating, after which the females were isolated. The eggs were placed on moist filter paper in petri dishes containing slices of ripe guava fruit. Egg-hatching was monitored daily and the number of larval instars established by measuring the width of their head capsules. The egg incubation period lasted 3.9 ± 0.58 days. The larval period was 16.0 ± 3.80 days and four instars were identified. After burrowing in the soil, the mature larvae (pre-pupa) remained underground for 142.0 ± 32.00 days and then pupated. The pupal period lasted 16.0 ± 0.90 days, but the adults remained underground for a further 34.0 ± 18.00 days. After emerging from the soil, adults lived 148.0 ± 89.00 days. Fecundity varied from 539 to 793 eggs/female, and the percent egg hatch was 96.5%.

Ixodid ticks (Acari: Ixodidae) present at Parque Nacional El Rey, Argentina

Abstract: Information on autochthonous ticks and their hosts is scarce in South America, especially in Argentina To contribute to tick knowledge in the region, 2094 ticks were collected from the vegetation, humans, domestic and wild animals at a host-and-tick rich area of northern Argentina during six field trips conducted in 1999 (January and August), 2000 (March and November), and 2001 (March and June) The ticks were identified as Amblyomma cajennense (Fabricius), Amblyomma coelebs Neumann, Amblyomma sp, Haemaphysalis juxtakochi Cooley, H leporispalustris (Packard), Ixodes pararicinus Keirans & Clifford, I loricatus Neumann, I longiscutatum Boero and Ixodes sp Small mammals were mainly parasitized by immature stages of Ixodes; humans and domestic animals, predominantly by Amblyomma spp, and birds, mainly by nymphs and larvae of Haemaphysalis spp

Larvicidal activity of Copaifera reticulata ducke oil-resin against Culex quinquefasciatus Say (Diptera: Culicidae)

Abstract: The appearance of resistance of Culex quinquefasciatus Say to chemical insecticides and the modification of the susceptibility of this mosquito to pyrethroid has stimulated studies on the activity of plants as alternative for its control. In this study, bioassays were carried out to verify the larvicidal activity of the oil-resin of Copaifera reticulata on C. quinquefasciatus. The bioassays were carried out with the oil dissolved in dimethylsulfoxide (DMSO), at the proportion of 0.4 ml of DMSO to 24.6 ml of distilled water. For each instar, the bioassays were carried out in plastic glasses with 100 ml solution using 20 larvae, wit four replications to adjust the lethal concentrations. The mortality observations were made after 48h exposure of the larvae to the solution. The control was carried out in distilled water and DMSO, with the same number of replications as the bioassays. The experiments were carried out in a biological chamber, controlled at 28 ± 1°C, 80 ± 5% relative humidity and 12h light. The larvae without movement were considered dead. The C. reticulata oil-resin demonstrated larvicide activity for all the C. quinquefasciatus instars. The LC50 found for the 1st, 2nd, 3rd and 4th larval instars were: 0.4, 0.9, 39 and 80 ppm, and the LC99 were 15, 15, 50 and 180 ppm, respectively.

Atratividade e preferência para oviposição de Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) biótipo B em genótipos de tomateiro

Abstract: Tomato genotypes of different species were evaluated regarding to attractiveness and oviposition preference of Bemisia tabaci (Gennadius) biotype B under greenhouse conditions. The experiment was conducted in a randomized block design, with a split-pot scheme and three replicates. Plant infestation was done at 40-45 days after seedling transplanting by introducing highly whitefly-infested soybean plants. The variables evaluated were adult number and egg number on the adaxial and abaxial surfaces of the leaflets, during five weeks. Each observation was composed by the mean numbers obtained for three leaflets. Leaf area of each genotype was determined to estimate whitefly population per cm2. There were no significant differences among genotypes and evaluations regarding to the presence of live adult whiteflies on the adaxial surfaces of the leaflets. For the number of live adult whiteflies on the abaxial surface, the least attractive genotypes were LA716 (Lycopersicon pennellii) and PI134417 (L. hirsutum f. glabratum); LA1609 (L. peruvianum) was one of the most attractive ones. Great number of dead adult whiteflies was registered on LA716, due to the sticky secretion produced by the glandular trichomes that cover leaves and stalks, trapping whiteflies when they contact the leaflet. Similar behavior was verified for LA1739, LA1740, PI127826 (L. hirsutum), PI134417 and PI134418 (L. hirsutum f. glabratum). LA716 and PI134418 were the least preferred genotypes for oviposition. The preferred genotypes for oviposition on the abaxial surface of the leaflets were CNPH1039, Japao (L. pimpinellifolium) and LA1609.

The flowering-visiting bees at the ecological station of the Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil

Abstract: The richness and the composition of bee species at the ecological station of the Universidade Federal de Minas Gerais, Campus Pampulha, Belo Horizonte, MG, Brazil, was recorded from January to December 1996. The bee fauna of the ecological station is rich (98 species) in low-density populations species (350 individuals). The composition of the bee fauna is seasonal (Q = 29.35, df = 11, P < 0.002), however the composition in flowering plants showed no seasonality (Q = 17.30, df = 11, P < 0,099). The bee species visited 23 flowering plant species from 11 families. Asteraceae (111 individuals in 53 species) and Convolvulaceae (88 individuals in 26 species) were the most visited families. There was a positive relation between bee abundance and the number of flowering plants (r2 = 0.72, P = 0.0011, n = 12) and bee richness and abundance of flowering plants (r2 = 0.46; P = 0.010, n = 12). In the studied area and other sites at Southeastern Brazil, Apidae was the richer and abundant family and Halictidae was the richer and abundant at South Brazil. Despite its localization in a heavily urbanized area, the ecological station supports a rich bee species assembly.

Biodiversity of frugivorous flies (Diptera: Tephritoidea) captured in citrus groves, Mato Grosso do Sul, Brazil

Abstract: This paper presents a faunistic analysis of the frugivorous species of Tephritoidea (Diptera) captured in three citrus groves in the municipalities of Anastacio (Chacara Laranjal, 20o 31' 36'' S, 55o 50' 12'' W, 170 m) and Terenos (Chacara Suzuki, 20o 26' 12" S, 55o 04' 54'' W, 308m), MS, Brazil, during a 25 month period. McPhail traps with 5% hydrolyzed corn protein were hung in Citrus sinensis (L.) and C. reticulata (L.) trees, spaced 30 m apart. The Tephritidae species caught were: Anastrepha alveatoides Blanchard, A. bezzii Lima, A. castanea Norrbom, A. daciformis Bezzi, A. dissimilis Stone, A. distincta Greene, A. fraterculus (Wied.), A. grandis (Macquart), A. haywardi Blanchard, A. leptozona Hendel, A. macrura Hendel, A. montei Lima, A. obliqua (Macquart), A. pickeli Lima, A. punctata Hendel, A. rheediae Stone, A. serpentina (Wied.), A. sororcula Zucchi, A. striata Schiner, A. turpiniae Stone, A. undosa Stone, A. zenildae Zucchi, three undescribed species - Anastrepha sp.1, Anastrepha sp.2; Anastrepha sp.3 and Ceratitis capitata (Wied.). The frugivorous Lonchaeidae caught were: Dasiops sp.; D. inedulis Steyskal, Lonchaea sp. and Neosilba spp. The Mediterranean Fruit Fly, C. capitata, was the most abundant and frequent, being the dominant species in the groves of both municipalities. In the Citrus grove in Anastacio the most abundant species were: Anastrepha daciformis, A. obliqua, A. pickeli, A. punctata, A. sororcula and A. fraterculus. In the Citrus groves in Terenos, A. dissimilis, A. punctata, A. sororcula, A. daciformis, A. striata and A. pickeli were the most abundant species.

Suscetibilidade de Plutella xylostella (L.) (Lepidoptera: Plutellidae) aos fungos Beauveria bassiana (Bals.) Vuill. e Metarhizium anisopliae (Metsch.) Sorok

Abstract: An initial screening was undertaken using the isolates ESALQ 447, ESALQ 760, ESALQ 900, ESALQ 634, IPA-205 and ESALQ 760 of B. bassiana, and ESALQ E9, IPA-207, ESALQ 860, IPA-204 and UFPE 3027 of M. anisopliae at the concentration of 108 conidia/ml for the diamondback moth (DBM) second instar. All isolates tested caused DBM larval mortality ranging from 70% to 96%, except the M. anisopliae isolate UFPE 3027, which resulted in a mortality of 26%. Based on this survey the isolates ESALQ 634 and ESALQ 447 of B. bassiana and IPA-207 and ESALQ E9 of M. anisopliae were chosen and assessed at the concentrations 105, 106, 107 and 108 conidia/ml for DBM second instar. These selected isolates at concentrations higher than 106 conidia/ml caused DBM larval mortality ranging from 58% to 96%. The mean lethal time (LT50) for DBM second instar were 1.1 and 4.3 days, and 0.7 and 5.8 days for B. bassiana isolates ESALQ 634 and ESALQ 447 and M. anisopliae isolates IPA-207 and ESALQ E9, respectively. Based on the lethal concentrations (LC50) the isolates IPA-207 and ESALQ E9 were seven times more virulent to DBM second instar than B. bassiana isolates ESALQ 634 and ESALQ 447. These results showed that DBM larvae were more susceptible to M. anisopliae than to B. bassiana and that M. anisopliae isolates IPA-207 and ESALQ E9 may be a valuable component for the integrated management of DBM larvae.

Nymphal development, lipid content, growth and weight gain of Nezara viridula (L.) (Heteroptera: Pentatomidae) fed on soybean genotypes

Abstract: The effects of five soybean [Glycine max (L.) Merrill] genotypes ('BR-16', 'IAC-100', PI 227687, PI 229358, PI 274454) on nymphal development, adult weight and lipid content of the stink bug Nezara viridula (L.), were evaluated in the laboratory. When fed on the pods of PI 227687 (resistant) and of 'BR-16' (susceptible) nymph mortalities were respectively 66.2% and 27.5%. Second instar nymphs, maintained since hatching in petri dishes containing PI 274454 and 'BR-16' pods, weighed 1.1 mg and 1.0 mg, respectively; they were heavier than those fed with PI 227687 (0.7 mg) and 'IAC-100' (0.7 mg) pods. Adult fresh weights were 146.9 mg when fed on 'BR-16', 127.0 mg with PI 227687 and 125.5 mg with 'IAC-100'. The later two genotypes also negatively affected stink bug weight gain. Females accumulated less lipid when fed on 'IAC-100' (4.8 mg) and PI 227687 (4.3 mg) than those fed on the other genotypes. By their deleterious effects, PI 227687 is confirmed as an inadequate food to N. viridula and as the most promising genotype for use in soybean breeding programs as sources of resistance to stink bug.

Development of Melittobia australica Girault and M. digitata Dahms (Parker) (Hymenoptera: Eulophidae) parasitizing Neobellieria bullata (Parker) (Diptera: Sarcophagidae) puparia

Abstract: The development of Melittobia australica Girault and M. digitata Dahms were studied parasitizing blow fly puparia Neobellieria (=Sarcophaga) bullata (Parker) using from one to five foundress females per host. Aspects of parasitoids biology such as number of descendents produced, longevity, and progeny body size can be affected as the number of foundress increases per host. The percentage of puparia parasitized was higher overall for M. digitata than for M. australica. Regardless of foundress numbers, the average total number of descendents produced was significantly higher for M. digitata (66.5 158.0) than for M. australica (10.9 55.5). The number of descendents produced per female was inversely proportional to the number of foundresses on a host for both species. Developmental time increased for M. australica and decreased for M. digitata, as the number of foundresses increased. Life spans of adult progeny of both species, deprived of host and food, were longer for progeny derived from fewer foundresses. Body size as measured by forewing and hind-tibia lengths of descendents showed significant reduction as number of foundresses increased for both species, except for the forewing of M. digitata. Changing foundress number did not affect offspring sex ratios (0.95 0.98 for M. australica, and 0.95 0.97 for M. digitata). These results indicated that M. digitata achieved better performance parasitizing N. bullata compared to M. australica, and both parasitoid species had their performance affected by increasing the parasitoid densities per host, suggesting that progeny competition occurred.

Molecular identification of Trichogramma cacoeciae Marchal (Hymenoptera: Trichogrammatidae): a new record for Peru

Abstract: Discovery of male morphological characters for species identification was a great improvement in Trichogramma systematic. However, not all species could be easily identified. In some cases, the lack of males (thelytokous status of species that carry the Wolbachia symbiont) made Trichogramma identification impossible. This problem was solved via antibiotic and heating treatments for elimination of the bacteria and allowing the production of males. The only Trichogramma species reported in which thelytoky is not induced by bacterial infection is T. cacoeciae, so here another means of species identification is needed. This species was identified based on the ITS2 (Internal transcribed spacer 2) sequence, a modern technique that has been proved useful in providing a reliable identification of Trichogramma species. Here we report the first occurrence of T. cacoeciae in Peru and we discuss its distribution in South America.

Seleção na evolução de resistência a organofosforados em Leucoptera coffeella (Guérin-Mèneville) (Lepidoptera: Lyonetiidae)

Abstract: Pesticide resistance is an increasingly worldwide phenomenon and a serious agriculture concern. From these perspectives, understanding of pesticide resistance is necessary to devise resistance management strategies to slow its development. Insecticide use and migration of resistant individuals can influence resistance evolution. The selection and dispersion of insecticide resistance were studied on the ten populations of Leucoptera coffeella (Guerin-Meneville) collected from different coffee producing regions of the State of Minas Gerais that were grouped together. Based on canonical variate analysis, a similar resistance pattern was observed in the populations from the "Zona da Mata Mineira" region. The increase of the frequency of resistant individuals was correlated with a larger number of organophosphate applications and likely dispersion of resistant individuals. Considerations on pattern of the resistance in coffee leafminer and implications for management are discussed.

Exigências térmicas e tabelas de vida de fertilidade de Myzus persicae (Sulzer) (Hemiptera: Aphididae) em laboratório

Abstract: Universidade Estadual Paulista Faculdade de Ciencias Agrarias e Veterinarias Depto Fitossanidade

Stigmaeidae mites (Acari: Raphignathoidea) from Arecaceae of the Atlantic Forest in São Paulo State, Brazil

Abstract: This work reports the Stigmaeidae mites from native plants of the family Arecaceae, in areas of Atlantic Forest in the State of Sao Paulo. Samplings were conducted once in each season of the year 2000 in Cananeia, Pariquera-Acu, Piracicaba and Sao Pedro, on nine native species of palm trees. Two new species of Stigmaeidae were found and described, Agistemus palmae n. sp. and Agistemus caissara n. sp. Based on specimens from the State of Mato Grosso, Brazil, immature stages of Agistemus floridanus Gonzalez-Rodriguez, 1965 are described for the first time, while adult males and females of the same species are redescribed

Phytophagous arthropods associated with Solanum mauritianum Scopoli (Solanaceae) in the first Plateau of Paraná, Brazil: a cooperative project on biological control of weeds between Brazil and South Africa

Abstract: Solanum mauritianum Scopoli (bugweed), native to southern Brazil, is a major weed in South Africa where it has been targeted for biological control. In 1998, a cooperative project involving Brazilian and South African scientists was initiated to develop cooperative biological control studies involving native Brazilian plants that are invasive in South Africa. Surveys for natural enemies were carried out in the First Plateau of Parana, where the plant is particularly abundant and where the climatic conditions are similar to high altitude areas in South Africa that are invaded by S. mauritianum. Populations of S. mauritianum supported a diverse herbivore fauna, which included at least 34 insect species and one mite species. Five species with high biological control potential were collected: two flower-feeding, two leaf-feeding and one stem-boring species. Three of these species have been studied in quarantine in South Africa, one of which has already been released for the biological control of S. mauritianum, while a fourth species, Anthonomus morticinus Clark (Coleoptera: Curculionidae), was studied in the field in Brazil.

Caracterização morfológica de dez espécies de Trichogramma (Hymenoptera: Trichogrammatidae) registradas na América do Sul

Abstract: Foram estudadas dez especies de Trichogramma (T. acacioi Brun, Moraes & Soares, T. atopovirilia Oatman & Platner, T. exiguum Pinto & Platner, T. fuentesi Torre, T. galloi Zucchi, T. lasallei Pinto, T. lopezandinensis Sarmiento, T. nerudai Pintureau & Gerding, T. pintoi Voegele e T. rojasi Nagaraja & Nagarkatti), com base na morfologia dos machos. Os principais caracteres foram ilustrados com o auxilio da microscopia eletronica de varredura. Os novos registros de hospedeiro sao T. acacioi em ovos de Hamadryas feronia (L.) (Brasil), T. nerudai em ovos de Tuta absoluta Meyrick (Chile) e T. lasallei em ovos de Diatraea saccharalis (Fabricius) (Uruguai primeiro registro neste pais).

Impacto de iscas formicidas granuladas sobre a mirmecofauna não-alvo em eucaliptais segundo duas formas de aplicacação

Abstract: The effect of localized and systematic use of granulated bait for cutting ant control was assessed on a community of non-target ants in eucalyptus in the municipality of Bom Despacho, Minas Gerais State, Brazil The ants were collected in Winkler traps on three occasions: eight days before bait distribution, eight and sixty days after distribution by removing the mirmecofauna from 50 1-m2 samples of litter A total of 102 species was collected belonging to six sub-families The seven most frequent ant species were analyzed in more detail to assess more precisely the consequences of insecticide treatments The study showed that systematic control caused negative and more prolonged impact on the ant community than localized control

Triatominae (Hemiptera: Reduviidae): Systematic questions and some others

Abstract: The Neotropical Chagas' disease vectors are classified as members of the reduviid subfamily Triatominae. However, this classification has been suggested to be incorrect, and the suggestion has been treated as fact by some authors; the suggestion is that some (all?) groups in Triatominae had different nontriatomine reduviid ancestors. In this article I raise this question explicitly and ask other questions ancillary to it. I do not answer these questions. Of particular interest is the systematic position of Linshcosteus, the only genus of Triatominae all of whose species occur outside the New World (in India). Related to this question is that of the origin(s) of the several species and populations probably derived from the tropicopolitan Triatoma rubrofasciata (De Geer). Answering these questions is of more than academic interest, for if triatomines had more than one nontriatomine ancestor, and therefore are not phylogenetically close, it is impossible to generalize what is known about one group to others, and this inability may hinder control of these disease vectors. It is therefore vital (literally!) to determine if Triatominae is a holophyletic group and, if not, to determine which groups now classified as triatomines are related to which others. This determination may best be accomplished with a cladistic analysis of the genera now included in Triatominae. Some comments on cladistics are presented in an Appendix.