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Influence of seasonality on macroinvertebrate diversity associated with the aquatic fern Salvinia biloba Raddi
2020
Rennan Leite Martins Coutinho | Isabella Rodrigues Lancellotti | Arthur Ribeiro Flores | Marcelo Guerra Santos
Abstract. The genus Salvinia is composed of fast-growing floating ferns, capable of surviving in different environmental conditions. Some authors suggest that the relationships between this genus and macroinvertebrates may serve as water quality indicators. The present study aimed to determine the influence of seasonality and water quality on macroinvertebrate diversity associated with the Salvinia biloba Raddi. Water and fern were collected in rainy and dry seasons and was conducted a microbiological analysis of the water, as well as, the area of fern cover on the water, richness, and density of macroinvertebrates. Microbiological analysis of the water detected > 5,700 CFU/mL (rainy season) and 175 CFU/mL (dry season) of heterotrophic bacteria and was positive for total thermotolerant coliforms. The S. biloba cover on the water surface was 100% in the rainy and 30% in the dry season. In the rainy season, 142 macroinvertebrates were identified, divided into 12 morphospecies, with a density of 434 individuals/m3. In the dry season, there were 419 individuals in 14 morphospecies, with a density of 2,076 individuals/m3 exhibited. The highest species density recorded in the rainy season was for Chironomidae sp.1 (Diptera) (57.71%) and Odonata Zygoptera sp.1 (17.44%), and in the dry season, Chironomidae sp.2 (73.98%) followed by Gerromorpha sp.1 (Hemiptera), with 9.54%. The Sørensen similarity index between the two seasons was 53.84%. The higher density of Gerromorpha sp.1 in the dry season may indicate an increase in environmental integrity.
Show more [+] Less [-]Occurrence and ecological data on an exotic solitary bee accidentally introduced in Brazil
2020
Charles Fernando dos Santos | Cristiane Andrade de Barros | Rosana Halinski | Betina Blochtein
Currently, there is a global concern regarding exotic species due to, among other factors, their great ability to reproduce and spread rapidly through the novel environment. As such, these species often compete for nesting places and food resources or convey pathogens. Anthidium manicatum (Linnaeus) (Hymenoptera: Megachilidae) is a non-native solitary bee occurring in Brazil. This study aimed to collect data about the occurrence sites of this species to investigate the historical sequence of its spread throughout the country. Based on this, we estimated population data such as the number of males and females, phenology and bioclimatic niche overlap with native species. The occurrence records were retrieved from speciesLink and Global Biodiversity Information Facility. All analyses were performed in R. The collected data demonstrate that, except for the 1960s, the records of the occurrence of A. manicatum in Brazil are few and constant, being notified since the mid-1930s in at least nine Brazilian states. In total, 778 individuals were sampled, with males being recorded about 1.7 times more than females. This species seems to be bivoltine, with generations in May and November. Anthidium manicatum showed a low and moderate bioclimatic niche overlap with two native species, Anthidium sertanicola Moure & Urban and Anthidium latum Schrottky, respectively. These data provide relevant information on the biology and status of A. manicatum in Brazil. However, since most Brazilian scientific collections have not digitalized their data in the platforms consulted here, some ecological features described here may be underestimated.
Show more [+] Less [-]Performance of baited traps for integrated management of Hypothenemus hampei Ferrari (Coleoptera: Scolytinae) in a conilon coffee crop in Rondônia State, Brazil
2020
Moisés Santos De Souza | José Nilton Medeiros Costa | Marcelo Curitiba Espindula | Alexandre de Almeida e Silva
Hypothenemus hampei (Ferrari) is an important pest worldwide. Methods of monitoring and control using baited traps are not yet established in coffee plantations in the Brazilian Amazon. The objective of this work was to record, for the first time, results of the use of baited traps in coffee plantation located in Rondônia, in favor of the control and pest monitoring. Two areas were delineated: i) with use of the traps baited with ethanol/methanol (1:1), treatment; ii) without use of traps (control). For comparison of results, two factors were considered: damaged fruits (damage by H. hampei) and infested (H. hampei inside of fruits). It was observed higher levels of damaged fruits per plants in the control area compared to the area where traps were used. The density of the pest population per plants found on infested fruits was also higher in the control area compared to the trapping area. These results suggest that traps baited with ethanol/methanol (1:1) are an effective alternative for population control of pest also in the coffee plantations in Rondônia, where there is no such management with this tool. Use of the baited traps to monitor the insect accurately revealed that the flight stimulus of the colonizing females is influenced by values of the environmental variables. According to the results, colonizing females are more active in the afternoon. Therefore, in order to achieve more efficient control of H. hampei, the best time to apply control agents is between 2:00 pm and 6:00 pm.
Show more [+] Less [-]Bee species (Hymenoptera: Anthophila) in a Cerrado-Atlantic Forest ecotone: nesting habits related to foraging activity in a degraded forest fragment
2020
Leandro Pereira Polatto | Valter Vieira Alves Junior
The aim of this paper was to determine the species diversity and frequency of foraging performed by bees in fragment of degraded forest in a Cerrado-Atlantic Forest ecotone area, also considering the nesting habit of each species. The foraging frequency of each bee species in the main floral sources was recorded for 12 consecutive months. The nesting site was used to sort the bees into guilds: above-ground nesting bees, ground-nesting bees, and both below and above-ground nesting bees. The guild of ground-nesting bees had 24 species and accounted for 17.48 % of the foraging rate, while above-ground nesting bees were represented by 12 species which made 8.89 % of the foraging rate, and both below and above-ground nesting bees comprised five species which made 0.43 % of the foraging rate. Africanized honeybee performed 73.20 % of the foraging flight, and presented a broad food niche. Therefore, in the forest fragment studied, two types of impacts which make difficult the survival and maintenance of the native bee fauna were observed: the dominance over floral resources by the exotic species the Africanized honeybees; the small number of large trees.
Show more [+] Less [-]Sources of resistance to black aphid in cowpea varieties used as green grains
2020
Vinicius Borges | Daniel Rodrigues Nere | Leandro Carvalho da Silva | Marília Gomes Caminha | Ervino Bleicher | Cândida Hermínia Campos de Magalhães Bertini
Evaluation of resistance of Vigna unguiculata L. landraces, used as green beans, to Aphis craccivora Koch was tested. Eleven landraces and standard genotypes were used in a free choice protocol: BR 17-Gurguéia, VITA 7 (susceptible), BRS Guariba and TVu 408P2 (resistant). A completely randomized blocks design was used with six replicates. Seedlings were infested with five six-day-old adult insects. The number of alive adults after 48 h and of alive nymphs after 96 h was evaluated. The results evidenced that there are high genetic diversity among the landraces, the antibiosis as the main mechanism of resistance. By means of multivariate analysis we suggest crosses among the commercial cultivar BRS Guariba and the most dissimilar varieties CCE-088, CCE-075, CCE-013 and CCE-062 to obtain superior hybrids.
Show more [+] Less [-]Electrophysiologic and behavioral responses mediated by volatiles involved in the repellency of Apis mellifera (Lepeletier) (Hymenoptera: Apidae)
2020
Patricia Daniela da Silva Pires | Josué Sant'Ana | Ricardo Bisotto-de-Oliveira
Repellent volatiles to insects might be an important tool for management of bees in areas which the presence of these organisms is not required. This study aimed to evaluate the electroantennal and behavioral responses of Africanized honeybees (workers), Apis mellifera (Lepeletier) (Hymenoptera Apidae), at different ages, to benzaldehyde (BA) and methyl anthranilate (MA) and to evaluate the potential repellency of these compounds under field conditions. Laboratory tests were conducted to study electroantennographic responses (mV) and chemotactic behavior of worker bees aged 1-5 (young) and 20-30 (old) days in four choice olfactometer. Electrophysiological responses to each compound did not differ between young and old workers. Bees antennae (young) triggered significantly greater responses to BA, in the older ones, a higher response was observed to MA, both compared to control (ethanol). The threshold response to BA and MA was achieved at 10 µg/µL, both compounds repelled bees at the same dose in olfactometer. Treatments with BA and MA, in field conditions, were less visited by scouter honey bees than those without these compounds (control).
Show more [+] Less [-]Occurrence of Aetalion reticulatum (Linnaeus) (Hemiptera: Aethalionidae) on Dipteryx alata Vogel (Fabaceae) in Minas Gerais, Brazil
2020
Jaqueline da Silva Souza | Jardel Boscardin
The baruzeiro or baru (Dipteryx alata Vogel) is a tree species native to Brazil that is known for its production of edible nuts with high nutritional value. However, little is known about the insects associated with this forest species. Therefore, this study aims to document the occurrence of leafhoppers on baruzeiro trees in the state of Minas Gerais, southeastern Brazil. We therefore examined baruzeiro plants in an afforestation plot at the Universidade Federal de Uberlândia (18°43'33"S; 47°31'31"W) in August 2020, located in the municipality of Monte Carmelo, Minas Gerais. The leafhopper species was identified as Aetalion reticulatum (Linnaeus) (Hemiptera: Aethalionidae). The ant species Camponotus crassus Mayr (Hymenoptera: Formicidae) was found to feed on the honeydew released by leafhoppers, demonstrating facultative mutualism between the species. This is the first report of A. reticulatum on D. alata in Minas Gerais.
Show more [+] Less [-]Pinnaspis strachani (Cooley) (Hemiptera: Diaspididae) infesting neem trees (Azadirachta indica A. Juss., Meliaceae) in Bahia, Brazil
2020
Marcelo Tavares de Castro | Sandro Coelho Linhares Montalvão | Vera Regina dos Santos Wolff
Pinnaspis strachani (Cooley) (Hemiptera: Diaspididae), a highly polyphagous scale insect and a known pest of various crops, is reported for the first time infesting neem (Azadirachta indica A. Juss., Meliaceae) in Brazil. Infestations of this diaspidid were observed on the trunks, branches, and leaves of neem trees in Barreiras, Bahia, Brazil.
Show more [+] Less [-]First record of the association of a species of Lycaenidae (Lepidoptera) with Zornia latifolia Sm. (Fabaceae), and its parasitoid (Hymenoptera: Chalcididae) in Brazil
2020
Suianne Oliveira dos Santos Cajé | Jefferson Duarte de Melo | Erlande Lins da Silva | Iracilda Maria de Moura Lima
The family Lycaenidae (Lepidoptera) comprises over 6,000 described and widely distributed species. However, studies on interactions with other insects such as ants, parasitoids, and with food plants in the Neotropical region, are still scarce, even though such information are fundamental for better understanding the natural history of this taxonomic group. This study reports a new food plant to larvae of Lycaenidae species in the neotropics, as well as its parasitoid. A Lycaenidae larva was found and collected for immature stage observation under laboratory conditions. The larva fed on petals and seeds of Zornia latifolia Sm. (Fabaceae). Nineteen days after pupation in laboratory a larvipupal parasitoid of the genus Conura (Chalcididae) had egressed. This is the first report of tritrophic relationship amongst Z. latifolia, a Lycaenidae larva and its larvipupal parasitoid of the genus Conura in a periurban area near remnants of the Atlantic Forest, in Northeastern Brazil.
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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