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Egg parasitoids of the cassava hornworm (Erinnyis spp.) associated to cassava in the Pará State, Brazil
2020
Aloyséia Cristina da Silva Noronha | Dimison Garcia Blanco | Valmir Antonio Costa | Ranyse Barbosa Querino | Dênmora Gomes de Araújo | Norman F. Johnson
The aim of this study was to assess the occurrence and identify the egg-parasitoid species of the cassava hornworm (Erinnyis spp.) in cassava plants (Manihot esculenta Crantz - Euphorbiaceae), facilitating their usage in the biological control as a management strategy in the Pará State. During February to December of 2016, cassava hornworm eggs were collected in the Cassava Germplasm Bank area of the Embrapa Amazônia Oriental, located at the city of Belém, State of Pará. In the laboratory, eggs were separated in viable and parasitized and were daily observed until the hatching of the caterpillars and emergence of the parasitoids. The caterpillars were reared until reaching the adult stage and the sex determined at the pupae stage. A total of 482 eggs were collected, with a higher occurrence at March, and 244 caterpillars were obtained with sex ratio of 0.52 with 191 specimens reaching adult stage. Among these adults, 95.81% were Erinnyis ello (Linnaeus) and 4.19% Erinnyis alope (Drury). A total of 1,087 parasitoids were obtained from 131 eggs and belong to four Hymenoptera families: Platygastridae (Telenomus dilophonotae Cameron), Eulophidae (Chrysonotomyia sp. aff. serjaniae), Trichogrammatidae (Trichogramma marandobai Brun, Moraes & Soares) and Encyrtidae (Ooencyrtus sp.). The Erinnyis spp. eggs were mostly parasitized by T. dilophonotae, which was classified along with T. marandobai as constant. The occurrence of these natural enemies highlights the potential for natural biological control against Erinnyis spp.
Afficher plus [+] Moins [-]Efficiency of botanical extracts against Aphis craccivora Koch (Hemiptera: Aphididae) nymphs in Vigna unguiculata (L.) Walp
2020
Jefferson Auteliano Carvalho Dutra | Victor Emmanuel de Vasconcelos Gomes | Ervino Bleicher | Deivielison Ximenes Siqueira Macedo | Mirla Maria Mesquita Almeida
The present study aimed to evaluate the insecticidal activity of hydroalcoholic plant extracts on Aphis craccivora Koch nymphs in cowpea. The experiments were carried out under greenhouse conditions in a randomized block design with five repetitions. Hydrated ethanol was used as a solvent in the botanical extract preparation. Cowpea plants were infested with five female adult aphids, eleven days after planting. After 48 hours, the adults were removed from the plants, leaving the recently bred nymphs. The evaluation of the nymphs’ survival was carried out forty-eight 48 hours after the application of the plant extracts. The botanical extracts with more than 50% efficiency were: Allium tuberosum leaf, Caesalpinia ferrea leaf, Piper aduncum leaf, Carica papaya seed, Dieffenbachia picta leaf, Cucurbita moschata seed and the control treatment, Annona squamosa seed. The botanical extracts with less than 50% efficiency were: Allium sativum bulb, Anacardium occidentale leaf, Borreria verticillata leaf plus flower, Coffea arabica leaf and seed, Delonix regia leaf and flower, Euphorbia tirucalli leaf, Leucaena leucocephala leaf, Mimosa caesalpiniaefolia leaf, Nerium oleander leaf, Syzygium cumini leaf, endocarp and pericarp, Syzygium malaccense leaf, Zingiber officinale rizome and Ziziphus joazeiro leaf. The highest efficiency levels were obtained by D. picta and C. moschata, rendering these extracts suitable for field trials to further evaluate their efficieny against the cowpea black aphid.
Afficher plus [+] Moins [-]Description of nymphs and ontogenetic morphometry of Triatoma ryckmani Zeledón & Ponce, 1972 (Hemiptera: Heteroptera: Reduviidae: Triatominae)
2020
Dayse da Silva Rocha | Carolina Dale | João Aristeu da Rosa | Cleber Galvão
Triatoma ryckmani Zeledón & Ponce, 1972 is a species found in sylvatic habitat at Central America. Considered rare in the past and poorly studied, nowadays can be found inside houses with potential of dispersal and colonization. All five instars of T. ryckmani are described based on optical and scanning electron microscopy. The postembryonic development of the head analyzed by ontogenetic morphometry showed the largest changes occur in the first three instars. Information about morphology of the immature stages of disease vectors can be helpful in the identification process increasing speed and efficiency of control strategies.
Afficher plus [+] Moins [-]Diversity and abundance of mosquitoes (Diptera, Culicidae) in a fragment of Amazon Cerrado in Macapá, State of Amapá, Brazil
2020
Jose Ferreira Saraiva | Ahana Maitra | Raimundo Nonato Picanço Souto
The Neotropical region has the highest diversity of species, but despite this diversity, this region presents many sampling gaps. The objective of this study was to study the diversity of the mosquitoes of family Culicidae (Diptera: Culicomorpha) as well as to identify the mosquito vectors, in a fragment of Amazon Cerrado in Macapá, Amapá. Three collection methods (Shannon trap, CDC and active collection) were used, and the samples were collected between January to December 2006. 21 species were identified; 11 of them being vectors of malaria, dengue fever, yellow fever, Zika, chikungunya and filariasis; and three of them, Toxorhynchites h. haemorrhoidalis (Fabricius), Wyeomyia melanocephala Dyar & Knab and Wyeomyia aporonoma Dyar & Knab were recorded for the first time from Amapá. The present study contributes to the diversity of mosquitoes (Culicidae) that can be used in additional mapping studies to mitigate epidemic outbreaks in the state of Amapá.
Afficher plus [+] Moins [-]The use of crotalaria as possible indirect agent to control Aedes aegypti L. (Diptera: Culicidae)
2020
Barbara Clara Schneider | Adriana Maria Meneghetti | Denise Lange
Aedes aegypti L. (Diptera: Culicidae) is a vector of arboviruses associated with dengue, chikungunya, zika and yellow fever. Based on empirical knowledge, plants belonging to genus Crotalaria (Fabaceae) attract dragonflies, which are the main natural predator to A. aegypti and help controlling populations of this mosquito. The aim of the present study is to investigate (i) whether Crotalaria is a food source for A. aegypti and (ii) whether Crotalaria attracts predators to this mosquito, mainly dragonflies. The study was carried out from January to March 2018 in two Crotalaria spectabilis Roth (Fabaceae) cultivation fields, which covered 100 m2 (each) in Missal County, Paraná State, Brazil. Samples of all arthropods foraging on C. spectabilis were collected. Observations in situ were carried out to investigate whether A. aegypti individuals visit C. spectabilis flowers. In total, 14,967 arthropods were recorded foraging on C. spectabilis (288 in cultivation field 1 and 14,679 in cultivation field 2). Dragonflies and damselflies were recorded foraging on C. spectabilis crops, but no A. aegypti individual was recorded in active collections and observations in situ. These results indicate that C. spectabilis works as food source and/or place used by several arthropods to find preys. The incidence of dragonflies and damselflies flying in C. spectabilis monocultures indicates that these plants attract dragonflies, as well as that Crotalaria can help indirectly controlling A. aegypti populations.
Afficher plus [+] Moins [-]Frugivorous butterflies (Lepidoptera: Nymphalidae) as a habitat quality indicator in Cerrado urban fragment
2020
Ieza Aparecida Teles Porath | Rodrigo Aranda
The environmental monitoring programs used to assess the quality of the habitats are often common to insects, mainly as frugivorous butterflies, as easily accessible biological indicators. These have ample availability of information, an easy to perform and low cost study method, in addition to responding easily to environmental changes, making it an efficient tool in environmental diagnosis. The way or objective of this work was to inventory as frugivorous butterflies in two different points, edge and center of an urban fragment belonging to the Universidade Federal de Rondonópolis, state of Mato Grosso, using as an environmental indicator. As a hypothesis, it was believed to detect differences in species richness, the amount of composition and composition between two areas. A sampling was carried out between the months of February and May 2019, using 10 Van Someren-Rydon weapons, of which six were distributed at the edges and four in the center (interior) of the fragment. Take place as trapped collections once a week lasting three days at each event. 105 individuals belonging to nine species of Nymphalidae were captured, respectively, as subfamilies: Biblidinae (71), Satyrinae (31) and Charaxinae (03). There was no significant difference between species richness, quantity and composition in the edge area and in the center of the fragment.
Afficher plus [+] Moins [-]Spatial behavior of corn leaf aphid and syrphid flies in corn crop in the northeast of Pará
2020
José Marlon dos Santos Nascimento | Ivan Carlos Fernandes Martins | Marcello Neiva de Mello | Jhonatan Rocha da Silva | Maria Milena Oliveira Lima | Fábio Júnior de Oliveira | Lourival Dias Campos
The aim of this study was to verify the spatial and temporal behavior of corn leaf aphid (Rhopalosiphum maidis Fitch.) and hoverflies in corn crop in the municipality of Igarapé-Açu, northeast of Pará, Brazil, as well as the influence of adjacent areas on the occurrence of these insects. An experimental area of 1.0 ha (100 x 100 m) was used in the years 2015 and 2016, adjacent areas consisted of mango agroecosystem, pasture and secondary forest. The area was divided into grid with 100 plots of 100 m² (10 x 10 m). Ten plants were randomly selected, totaling 1,000 plants per sampling date. Corn leaf aphid colonies (= or> 15 aphid) and syrphid flies adult was visually analyzed throughout the aerial parts of the plants. The spatial behavior was analyzed by semivariogram modeling and kriging interpolation maps. The semivariograms and kriging maps were made by the R software for Windows. Gaussian, spherical and exponential models were the best fit for corn leaf aphid in both harvests, showing aggregate behavior. The strong and moderate spatial dependence index prevailed, with range ranging from 12.46 to 93.04 m for R. maidis. The syrphids flies showed spatial interaction with the corn leaf aphid and they also show aggregate behavior, confirmed by most adjustments in the spherical and exponential models. The spatial dependence index of the prevailing syrphids flies were moderate and weak, ranging from 14.00 to 101.33 m. Adjacent areas showed influence on occurrence and dispersal of both corn leaf aphid and syrphids flies.
Afficher plus [+] Moins [-]Strains of Spodoptera frugiperda (J.E.Smith) (Noctuidae) in the states of Paraná and São Paulo, Brazil
2020
Francielly Silveira Richardt | Adriana Micheli | Daniele Tasior | Elderson Ruthes | Luís Amilton Foerster
Two strains of Spodoptera frugiperda (J.E. Smith) were first described in the United States; in Brazil, in the states of Rio Grande do Sul, Mato Grosso, and western Paraná they have also been reported. This study was aimed at identifying these strains in Norte Pioneiro and Campos Gerais, in the states of Paraná and southwestern São Paulo. Larvae of S. frugiperda were collected in the cities of Ponta Grossa, Tibagi, Arapoti, and Wenceslau Braz in Paraná, and in the city of Itaberá, in São Paulo. PCR-RFLP genotyping of the COI gene was carried out using sixty-six specimens. Based on their electrophoretic pattern, 51 individuals were identified as corn strain, five as rice strain, and 10 as hybrids (Rice in MspI and Maize in SacI). Our findings indicate that both S. frugiperda strains are present the study areas.
Afficher plus [+] Moins [-]Infestation of Magulacra nigripennata Dognin (Lepidoptera: Cossidae) in a commercial cupuassu plantation in Nova Califórnia, Rondônia State, Brazil
2020
Rodrigo Souza Santos | Tadário Kamel de Oliveira | Giordano Bruno da Silva Oliveira | Taysa Faltz Macedo
The cupuassu (Theobroma grandiflorum (Willd ex Sprengel) K. Schum.) is a native tree from the tropical rainforest and one of the most important fruit trees in the Amazon region. Its pulp and seeds are widely used in the alimentary industry, as well as food by the people of northern Brazil. Among the factors that can compromise the production of cupuassu are the attack of diseases and insect pests. The aim of this work is to report the attack of a wood-borer lepidopteran in commercial cupuassu plantation located in the district of Nova Califórnia, Rondônia State, Brazil. In April 2019 an infestation of a wood-borer insect was observed causing the death of branches. Branches containing caterpillars in their inside were collected and taken to the Entomology Laboratory of the Embrapa Acre, where they were placed in a screened cage. After about 60 days, an adult insect emerged, which was identified as Magulacra nigripennata, a lepidopteran associated with cocoa and cupuassu plantations in that country. A random survey of 100 plants in the plantation area detected an infestation level of 36%, indicating the harmful potential of this pest to the cupuassu crops in the Amazon region.
Afficher plus [+] Moins [-]Infestation indices and characterization of injuries of Drosophila suzukii Matsumura (Diptera: Drosophilidae) in Barbados cherry
2020
Léo Rodrigo Ferreira Louzeiro | Miguel Francisco Souza-Filho | Adalton Raga | Carla A. Bulgarelli | Louis Bernard Klaczko
Females of Drosophila suzukii Matsumura (Diptera: Drosophilidae) have a serrated ovipositor that causes severe physical damage to soft fruit. This behaviour results in the early ripening and accelerated rotting of infested fruit. In addition, feeding by larvae softens of the fruit peel, causing in a depreciation in commercial value. In this study, results of infestation indices, pupal viability, egg-adult period, degradation time of infested fruit, and description of physical injuries caused by oviposition and larval feeding of D. suzukii in Barbados cherries (Malpighia emarginata DC., Malpighiaceae) are described. Overall, our results and discussion contribute to the understanding of the status of D. suzukii as an insect pest of the Barbados cherry.
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