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Differences in wings may be sufficient to separate the sexes and two species of Gynaikothrips Zimmermann (Thysanoptera: Phlaeothripidae)? Texte intégral
2022
Priscila Paredes dos Santos | Juvenal Cordeiro Silva Junior | Lorena Andrade Nunes
In this study, we use geometric morphometry to discriminate thrips of the species Gynaikothrips uzeli (Zimmerman) and Gynaikothrips ficorum (Marchal) and also to detect sexual dimorphism in these species. Two hundred individuals, one hundred females and one hundred males, from G. uzeli and G. ficorum, were used to verify sexual dimorphism. For interspecific differentiation, two hundred females were used, one hundred individuals of each species. It was possible to observe differences in the shape of the wing between sexes in both species. In G. uzeli, the first two main components explain 92.5% of the total variation of individuals. The first main component explains 87% and the second 5.5 of the total variation of individuals. For G. ficorum, the first two main components explain 78.2% of the total variation of individuals. The first principal component contributed with 62% and the second principal component with 16.2% of the variation of the shape of the wing. Besides, significant interspecific differences were observed in the shape of the wing, where the first two main components were sufficient to explain 86% of the total variation of the individuals. The first principal component explained 76.2% and the second 9.8% of the total variation of the individuals, being possible to verify differences in the shape of the wing of these two species. Geometric morphometry is a viable technique for assessing sexual dimorphism, as well as interspecific differences in the shape of the wings of these species, which are morphologically very similar.
Afficher plus [+] Moins [-]A new species of Paratropis Simon, 1889 (Araneae: Paratropididae) from Guyana Texte intégral
2022
Marlus Queiroz Almeida | José Wellington de Morais
A new species of Paratropis is herein described and illustrated, namely: Paratropis minusculus n. sp. based on males, females and immatures from Potaro-Siparuni, Guyana. Male e female of P. minusculus differ from those of all other species of the genus by having six eyes and by spinneret apical segment domed. In addition, we presented the first record of paratropidid species from Guyana, contribute to the knowledge of local biodiversity.
Afficher plus [+] Moins [-]Effects of different levels of artificial defoliation on the vegetative and reproductive stages of soybean Texte intégral
2022
Eires Tosta Fernandes | Crébio José Ávila | Ivana Fernandes da Silva
Effects of different levels of artificial defoliation on the vegetative and reproductive stages of soybean Texte intégral
2022
Eires Tosta Fernandes | Crébio José Ávila | Ivana Fernandes da Silva
Any factor that may limit the leaf area of the crop in soybean may compromise its development and, consequently, its productivity. The aim of the study was to evaluate the effect of different levels of artificial defoliation performed in the vegetative and reproductive stages of two soybean cultivars, FT Campo Mourão and Brasmax Potência. The treatments consisted in: 1) Without defoliation throughout the culture cycle; 2) 16.7% defoliation in the vegetative stage; 3) 33.3% on vegetative stage; 4) 16.7% on reproductive stage; 5) 33.3% on reproductive stage; 6) 16.7% throughout the soybean cycle; 7) 33.3% defoliation throughout the soybean cycle. Regardless of the level of defoliation performed on soybeans, it was found that the cultivar Brasmax Potência presented the higher values of plant height, number of pods/plant and green weight of the aerial part, when compared to cultivar FT Campo Mourão. However, the number of pods/plant, green weight of the areal part, grain yield and weight of the seeds were not influenced by the defoliation intensities applied to the soybean. Based on the results, the threshold level of 30% of defoliation in the vegetative stage or 15% in the reproductive stage of soybean is still considered valid for the control of defoliating caterpillars in soybean crop.
Afficher plus [+] Moins [-]Effects of different levels of artificial defoliation on the vegetative and reproductive stages of soybean. Texte intégral
2022 | 2023
FERNANDES, E. T. | AVILA, C. J. | SILVA, I. F. DA | EIRES TOSTA FERNANDES, UNIVERSIDADE FEDERAL DA GRANDE DOURADOS, DOURADOS; CREBIO JOSE AVILA, CPAO; IVANA FERNANDES DA SILVA.
Any factor that may limit the leaf area of the crop in soybean may compromise its development and, consequently, its productivity. The aim of the study was to evaluate the effect of different levels of artificial defoliation performed in the vegetative and reproductive stages of two soybean cultivars, FT Campo Mourão and Brasmax Potência. The treatments consisted in: 1) Without defoliation throughout the culture cycle; 2) 16.7% defoliation in the vegetative stage; 3) 33.3% on vegetative stage; 4) 16.7% on reproductive stage; 5) 33.3% on reproductive stage; 6) 16.7% throughout the soybean cycle; 7) 33.3% defoliation throughout the soybean cycle. Regardless of the level of defoliation performed on soybeans, it was found that the cultivar Brasmax Potência presented the higher values of plant height, number of pods/plant and green weight of the aerial part, when compared to cultivar FT Campo Mourão. However, the number of pods/plant, green weight of the areal part, grain yield and weight of the seeds were not influenced by the defoliation intensities applied to the soybean. Based on the results, the threshold level of 30% of defoliation in the vegetative stage or 15% in the reproductive stage of soybean is still considered valid for the control of defoliating caterpillars in soybean crop.
Afficher plus [+] Moins [-]Occurrence of Megaselia scalaris Loew (Diptera: Phoridae) in Mischocyttarus cassununga Von Ihering (Hymenoptera: Vespidae: Polistinae) nests Texte intégral
2022
Sheliane Cristina Coelho Francisco | Gabriel de Castro Jacques | Luís Cláudio Paterno Silveira
Social wasp nests create an environment rich in resources, such as food and shelter, which consequently attract predators, parasites, and parasitoids. Parasitoids attacks can be one of the main causes of mortality among social wasps in the early stages of development. Therefore, the aim of this work is to report the occurrence of parasitoids in Mischocyttarus cassununga Von Ihering (Hymenoptera: Vespidae: Polistinae) nests, in an area of Cerrado, at the Federal Institute of Education, Science and Technology of Minas Gerais (IFMG) - Campus Bambuí, Brazil. There was an emergence of four parasitoids from two nests of M. cassununga, identified as Megaselia scalaris (Loew) (Diptera: Phoridae), the first record of this parasitoid in M. cassununga in a Cerrado area.
Afficher plus [+] Moins [-]Nectarivore butterflies (Lepidoptera: Papilionoidea) from an Urban Forest Fragment in Manaus, Amazonas Texte intégral
2022
Kelve Franklimara Sousa Cézar | Rosamary Silva Vieira | Gilcélia Melo Lourido
Lepidoptera is a diverse and abundant group of insects, widely used in biodiversity and conservation studies, as it has great social appeal. From this perspective, this study was aimed to conduct a survey of flower – visiting butterfly species in Bosque da Ciência, at the Instituto Nacional de Pesquisas da Amazônia (INPA), an urban forest fragment open to public visitation in the State of Amazonas, Brazil. Thus, attractive plants for nectarivorous butterflies were observed, and the best location and conditions for viewing such diversity, as well as a guide for their identification was proposed. Forty-three species of flower – visiting butterflies were identified, among which Anthoptus epictetus (Fabricius), Ascia monuste (Linnaeus), Anartia jatrophae (Linnaeus), Eurema albula (Cramer) were observed to be more frequent. According to the species accumulation curve, the species richness of butterflies would be higher if greater collection effort were employed. The period of greatest flight activity and flower - visitation occurred from 9 am to 11 am. Of the six attractive plants identified, Stachytarpheta cayennensis (Rich.) and Lantana camara L. were the most visited, so we consider that these species are important for butterfly attractiveness. The butterflies of Bosque da Ciência are a representation of the nectarivores guild of the city of Manaus, Amazonas, and the establishment of an attractive butterfly garden in this place can contribute to the promotion of environmental education by stimulating the knowledge and awareness for biodiversity preservation.
Afficher plus [+] Moins [-]Ant diversity (Hymenoptera: Formicidae) in two districts in the municipality of Barreiras-BA Texte intégral
2022
Juliana Luiz dos Santos | Greice Ayra Franco-Assis | Graziella Diógenes Vieira Marques
In recent years, attention has focused on studies about myrmecofauna in urban environments, due to its high possibility of causing damage to food storage and household structures. Thus, the objective of this study was to identify the genera of ants and analyze their frequency and diversity in two neighborhoods in the municipality of Barreiras-BA. The study was conducted in Riachinho neighborhood, located on the edge of the urban perimeter and in Renato Gonçalves neighborhood in the central area of the city. The ants were collected weekly, using trap baits, in 180 houses, from November 2016 to April 2017. The collected ants were transported to the Zoology and Entomology Laboratory (LaZooEn) in the Universidade do Estado da Bahia, Campus IX. For identification, stereomicroscope and dichotomous key were used. A group of 14,846 ants were collected, of which 9,686 were collected in Renato Gonçalves neighborhood, and 5,160 in Riachinho neighborhood. Three subfamilies were identified, which included ten genera, being Paratrechina, Brachymyrmex and Tapinoma were among the most frequent. Paratrechina was the most representative (85.32%) in Riachinho, and Brachymyrmex, the most frequent in Renato Gonçalves (54.40%). The accumulation curves obtained were satisfactory in both areas, higher than 80%. Regarding Shannon index, it was found that Riachinho presented a lower diversity (H'= 0.663) than in Renato Gonçalves neighborhood (H'= 0.875). Studies addressing the occurrence of myrmecofauna may be paramount to collaborate with conservation practices both in the case of threatened species and for pest control practices.
Afficher plus [+] Moins [-]Faunistic composition of hymenopteran parasitoids in cultivation of Eucalyptus urophylla S.T. blake and adjacent areas of Seasonal Semi-deciduous Montana forest situated in the Semi-arid State of Bahia, Brazil Texte intégral
2022
Rita de Cássia Antunes Lima de Paula | Jennifer Guimarães Silva | Daniell Rodrigo Rodrigues Fernandes | Aldenise Alves Moreira | Onice Teresinha Dall’Oglio | Juvenal Cordeiro Silva Junior | Raquel Pérez-Maluf
Hymenopteran parasitoids are insects that play a fundamental role in ecosystems as they reduce the population density of insects that are considered pests in monocultures. However, little is known about the fauna in association to the eucalyptus trees in comparison to adjacent native vegetations. Therefore, this study was aimed to determine the fauna of parasitoid wasps that occur in a commercial plantation of Eucalyptus urophylla S.T. Blake, as well as in native forest and capoeira environments in the plateau of Conquista, Bahia, a semiarid region of Bahia. The study was conducted for two consecutive years with monthly monitoring using five Malaise traps. The collected insects were sorted and identified at the family level. The faunal indices referring to the families of each area were studied by evaluating the frequency, species richness, shannon diversity and equitability. In total, 5,899 individuals were collected, which were distributed in 24 families and eight superfamilies. The most abundant families were Braconidae, Ichneumonidae and Bethylidae. Capoeira and eucalyptus trees showed greater similarity and equitability when compared to the rest of the forest. Given the diversity of Hymenopteran parasitoid families found in the area, it was concluded that the maintenance of native vegetation environments is important, even at the initial stage of succession.
Afficher plus [+] Moins [-]Two new occurrences of Oligonychus (Acari: Thrombidiformes: Tetranychidae) in Coffea canephora Pierre ex. Froehner, with description of damage and record of its natural enemies in the state of Amazonas, Brazil Texte intégral
2022
Geraldo José Nascimento de Vasconcelos | Andrey Luis Bruyns de Sousa | Indalecio Khalled Eufrazio Soares | Fábio Medeiros Ferreira
The objectives of this work were to document two new occurrences of Oligonychus (Trombidiformes: Tetranychidae) in coffee plant, present the damage and climatic conditions that may have favored the high population at the time of records, and report the occurrence of natural enemies. The records were done in three production areas in Itacoatiara, Silves, and Urucará, state of Amazonas. We verified the occurrence of Oligonychus mangiferus (Rahman and Sapra) and Oligonychus peronis Pritchard and Baker. In two crops, O. mangiferus was observed causing severe damage, probably due to favorable climatic conditions which coincided with the peak of the dry season in the region. For both species, we observed the occurrence of natural enemies such as predatory insects and mites, and acaropathogenic fungus. Based on the results, the occurrence of O. mangiferus and O. peronis in coffee farming is now known. These pests, especially O. mangiferus, can damage crops during the dry season.
Afficher plus [+] Moins [-]Composition of Anopheles Meigen (Diptera: Culicidae) in a peri-urban area of the Eastern Amazon Texte intégral
2022
Keison de Souza Cavalcante | Taires Peniche | José Rodrigues Júnior | Geandro dos Santos Gama | Flávia Montagner | Allan Kardec Ribeiro Galardo
Malaria vector mosquitoes belong to the genus Anopheles Meigen. The Amazon has been changing due to economic activities such as mining, logging, agriculture, and urbanization, leading to changes in malaria transmission patterns in this region. Therefore, this study aimed to survey Anopheles species in a peri-urban area of Macapá, state of Amapá, Eastern Amazon, Brazil. Human landing catches (HLC) and Shannon light traps were used to collect Anopheles adults at three points. We screened breeding sites in all accessible water reservoirs within a 2 km radius of each collection point to collect immatures and found two species: Anopheles (Nyssorhynchus) albitarsis s.l. Lynch-Arribalzága (35.7%) and Anopheles (Nyssorhynchus) braziliensis (Chagas) (64.3%). A total of 267 winged specimens of Anopheles were collected: A. (N.) braziliensis (62.9%), Anopheles (Anopheles) mattogrossensis Lutz & Neiva (11.6%), Anopheles (Nyssorhynchus) triannulatus s.l. (Neiva & Pinto) (11.6%), A. (N.) albitarsis s.l. Lynch-Arribálzaga (6.7%), Anopheles (Nyssorhynchus) darlingi Root (5.2%), Anopheles (Anopheles) peryassui Dyar & Knab (1.5%), and Anopheles (Nyssorhynchus) nuneztovari Galbadón (0.4%). Considering that Macapá has autochthonous malaria cases, our findings can contribute to developing public health measures in this municipality, therefore helping to protect its habitants.
Afficher plus [+] Moins [-]Occurrence of Eubulus sp. (Coleoptera: Curculionidae) in fruits of Alibertia edulis (Rich.) A. Rich. (Rubiaceae) in the Cerrado of Minas Gerais, Brazil Texte intégral
2022
Jardel Boscardin | Jaqueline da Silva Souza
The puruí Alibertia edulis (Rich.) A. Rich. (Rubiaceae) is a naturally occurring species in the Cerrado biome in Brazil; its fruits serve as food for the local fauna (birds and mammals) and humans. Here, we report on a beetle feeding on the fruits of A. edulis in the Cerrado of Minas Gerais (MG). Monthly collections were carried out in four A. edulis trees in two areas of Cerradão in the vicinity of the municipality of Monte Carmelo, MG, between September and October 2018. These were a legal reserve area of Fazenda Juliana (ARL; Juliana Farm; 18°42'30 "S and 47°33'05 "W) and an area at the Atalho Community (ACA; 18°41'39 "S and 47°34'49 "W). Fruits with or without attack symptoms were collected from the treetop in the four cardinal directions. A total of 100 fruits (50 from each area) were collected from the trees and packed into plastic bags. The fruits were then transported to the laboratory, stored in plastic containers isolated with voile fabric, and checked daily for the emergence of adult insects. After emergence, the insects were identified. During the evaluation period, 33 beetles emerged in puruí fruits from ARL and 13 from ACA. The species has been identified as Eubulus (Kirsch) sp. (Coleoptera: Curculionidae). The animals consumed the entire fruit endocarp, leaving it with emergence orifices caused by the adult emergence. It is concluded that Eubulus sp. feeds on the pulp of A. edulis and is able to compete for this resource with other animal species.
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