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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.
Show more [+] Less [-]Treatment of bean seeds (Phaseolus vulgaris L.) with systemic insecticides for the management of Cerotoma arcuata (Olivier) (Coleoptera: Chrysomelidae)
2020
Igor Honorato Leduino da Silva | Waldiane Araújo de Almeida | Adalberto Hipólito de Sousa
Bean (Phaseolus vulgaris L.) cultivation has great agricultural and food importance, but this crop production is generally affected by severe infestations of Cerotoma arcuata (Olivier) (Coleoptera: Chrysomelidae) in the northern region of Brazil. An alternative for leaf beetle control is the use of physiological insecticides acting in the initial phase of plant growth, through pre-sowing seed treatment. In this sense, this study aimed to evaluate the effects of systemic insecticides, based on thiamethoxam, imidacloprid and fipronil, on the germination performance of bean seeds, and to verify the efficacy of these insecticides on the control of C. arcuata. The research was carried out in two stages. Initially, under laboratory conditions, the influence of the insecticides on the germinating power of seeds was evaluated through the following parameters: germination, emergence, electrical conductivity and dry mass of the aerial part. In the field, the efficacy of the insecticides on the plant stand, number of insects per plant and level of foliar damage at 21 and 28 days of planting were evaluated. The insecticides investigated did not affect the germinating power of seeds when compared to the control. Regarding field results, there was a lower incidence of C. arcuata and less leaf damage to plants from seeds treated with systemic insecticides, showing greater crop protection in the period studied.
Show more [+] Less [-]Entomological profile and new registers of the genera Anopheles (Diptera, Culicidae) in a Brazilian rural community of the District of Coxipó do Ouro, Cuiabá, Mato Grosso
2020
Adaiane Catarina Marcondes Jacobina | Jozeilton Dantas Bandeira | Fábio Alexandre Leal dos Santos | Elisangela Santana de Oliveira Dantas | Diniz Pereira Leite-Jr
The order Diptera is constituted of insects that possess numerous varieties of habitats, these winged, commonly called mosquitoes, comprise a monophyletic group. Malaria transmitters in Brazil are represented by mosquitoes of the Anopheles genus, being it principal vector species Anopheles (Nyssorhynchus) darlingi Root. Collectings were accomplished in the rural area of Cuiabá in the region of Coxipó do Ouro/MT, and a total 4,773 adult mosquitoes of the genus Anopheles were obtained. The prevailing species in the collectings where An. (Nys.) darlingi with 3,905 (81.8%), considered the vector of major epidemiological expression in the region, followed by Anopheles (Nyssorhynchus) argyritarsis (Robineau-Desvoidy) 267 (5.6%) and Anopheles (Nyssorhynchus) triannulatus (Neiva & Pinto) 226 (4.7%). This report might be useful to entomological surveillance, demonstrating that the Coxipó do Ouro/MT locality might be elected as an area to be monitored, once the presence of such vector in this type of environment indicates a potential malaria transmission risk for the neighbouring regions in the state of Mato Grosso.
Show more [+] Less [-]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.
Show more [+] Less [-]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.
Show more [+] Less [-]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.
Show more [+] Less [-]Elio Corseuil: Obituary (1930-2020)
2020
Flávio Roberto Mello Garcia | Alexandre Specht | José Augusto Teston
Elio Corseuil (20/07/1930-26/07/2020)
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