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1.
Syst Parasitol ; 101(4): 44, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38839661

RESUMO

Species of Diolcogaster parasitize Lepidoptera pests of commercial plants. The diversity of this genus is high, but few species of Diolcogaster have been described. The description of a new Diolcogaster species provides information for the biological control using this insect. This study presents the description and key notes on the biology of a new Diolcogaster parasitoid wasp. This species was reared from a caterpillar of Hypercompe brasiliensis collected after feeding on a Gloxinia perennis plant important to floriculture. Two complementary identification analyzes were performed on Diolcogaster adult bodies. The first was the analyses of its external morphology and the second its molecular analysis (mitochondrial DNA). The morphological analysis defined the insect as a new species of Diolcogaster, named Diolcogaster joanesi sp. nov. A maximum-likelihood (ML) analysis partially confirmed the morphological analysis, placing D. joanesi within a cluster including a previously identified species (Diolcogaster choi) and seven other morphospecies. The proximity of D. joanesi to D. choi is discussed and an updated key for all New World species of the xanthaspis group is provided. Twenty-eight adult wasps were obtained (22 females and six males) out of 50 cocoons which larvae emerged from the caterpillar host. The findings contribute to the broader understanding of Diolcogaster in the Neotropics and its potential for the biological control of lepidopteran defoliators.


Assuntos
Controle Biológico de Vetores , Especificidade da Espécie , Vespas , Animais , Brasil , Vespas/classificação , Vespas/anatomia & histologia , Mariposas/parasitologia , Lepidópteros/parasitologia , Filogenia , Larva , Feminino
2.
An Acad Bras Cienc ; 95(1): e20191295, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36946799

RESUMO

The ground beetle, Neoaulacoryssus speciosus (Coleoptera: Carabidae) is of high relevance to field because it has been recorded as a pest of seeds and young plants of vegetables and other crops and a predator in agricultural crops, forest and weeds in Brazil. However, natural habitat changes are increasing agriculture and forest insect outbreaks in urban areas. A N. speciosus population outbreak occurred in October and November 2018 simultaneously in 12 neighboring municipalities at the beginning of the rainy season in the northern region of Minas Gerais State, Brazil. The objectives of this study were to report a sudden and simultaneous population outbreak of N. speciosus and to describe the factors of habitat change that could have contributed to this invasion in 12 municipalities in the northern region of Minas Gerais State in the Caatinga biome of Brazil. In addition, female and male genitals were described and illustrated, the scientific classification revised and common names of N. speciosus listed. Thousands of males and females of N. speciosus agglomerated in shady, humid places during the day and night for about 15 days. Neoaulacoryssus speciosus has been identified and illustrated, its scientific classification revised and four common names listed for this species.


Assuntos
Besouros , Florestas , Animais , Masculino , Feminino , Cidades , Surtos de Doenças , Chuva , Brasil/epidemiologia
3.
An Acad Bras Cienc ; 95(4): e20191305, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38126611

RESUMO

Production and sale of botanical insecticides depend on knowing the potential opportunities for these products. Essential oils from plants secondary metabolism can control pests, especially in agricultural systems where synthetic insecticides are limited, as in organic agriculture. The objective of this study was to evaluate the toxicity of essential oils to Diaphania hyalinata (Lepidoptera: Crambidae) and to show regions with the potential to use Cinnamomum zeylanicum, Citrus sinensis, and Syzygium aromaticum in the formulation and commercialization of insecticides to control this insect. The C. zeylanicum oil was more toxic to larvae and pupae and the S. aromaticum to eggs of D. hyalinata. Essential oils are an alternative for the management of D. hyalinata. The production of pesticides from essential oils of C. zeylanicum, C. sinensis, and S. aromaticum to control D. hyalinata has high potential in America. Also, Asia, Africa, Europe, the Middle East, and Asia can extract these plants to formulate insecticide molecules for the America countries.


Assuntos
Inseticidas , Mariposas , Óleos Voláteis , Animais , Inseticidas/farmacologia , Óleos Voláteis/farmacologia , Verduras , Larva , Óleos de Plantas
4.
An Acad Bras Cienc ; 94(suppl 3): e20211566, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36417614

RESUMO

Cultivation of species of the genus Eucalyptus is important for the Brazilian economy, with 6.97 million hectares planted. Glycaspis brimblecombei Moore (Hemiptera: Aphalaridae), detected in Brazil in 2003, has dispersed and now damages Eucalyptus crops in all regions of this country. The location and identification of entomopathogenic fungi isolates may increase the options for integrated pest management. The objective of this research was to evaluate the pathogenicity of Cordyceps cateniannulata and Cordyceps javanica isolates to G. brimblecombei. Ten nymphs of G. brimblecombei, with or without lerps, were placed per Eucalyptus leaf cut with one of its edges on hydroretentive gel inside Petri dishes. The fungi isolates were suspended in a solution of Tween 80 (0.1%) at the concentration of 1.0 x 108 conidia mL-1 and sprayed on the G. brimblecombei nymphs. The mortality of this insect was evaluated daily for seven days, and the dead individuals were transferred to humid chambers. The conidia viability of the isolates was greater than 93%. The mortality of G. brimblecombei nymphs, seven days after the application of the fungi, was 100%. This is the first report of the pathogenicity of C. cateniannulata and C. javanica isolates, occurring naturally in the field, to G. brimblecombei.


Assuntos
Cordyceps , Eucalyptus , Hemípteros , Animais , Esporos Fúngicos , Virulência
5.
An Acad Bras Cienc ; 93(4): e20190943, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34586311

RESUMO

Entomopathogenic nematodes (EPNs) can control pests due to their mutual association with bacteria. The use of these biological control agents is increasing worldwide due to advances in research about its control efficiency, range of action and mass production. The identification of EPNs adapted to specific environmental and climatic conditions is important for sustainable pest suppression in integrated management (IPM) programs. The objective is to report, for the first time, the occurrence of the Steinernema diaprepesi in Brazil. Steel mesh traps with Galleria mellonella Linnaeus (Lepidoptera: Pyralidae) larvae were buried in red latosol cultivated with Eucalyptus. Infective juveniles (IJs) were isolated from dead larvae and multiplied in healthy ones of this host to confirm its pathogenicity and to start a laboratory population from the strain found in the field. The DNA of the IJs was extracted and amplified using PCR technique with the universal primers D2A and D3B. The detection of S. diaprepesi is the first report of this nematode in Brazil, increasing the knowledge about its distribution in the world and the diversity of EPNs that must be considered as agents of biological pest control in the country.


Assuntos
Mariposas , Rabditídios , Animais , Brasil , Larva , Controle Biológico de Vetores
6.
J Insect Sci ; 21(2)2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33822128

RESUMO

The coffee berry borer (CBB), Hypothenemus hampei Ferrari (Coleoptera: Curculionidae), is the most important coffee pest in most of the coffee growing countries. CBB females leave old dry berries after harvest and search for dry noninfested berries on the plant or on the ground to lay eggs or to use as refuge until new berries are available on the coffee trees in the following season. The CBB infestation level and emergence from berries on the ground or on the plants were evaluated in two fields post-harvest in the Spring in Brazil over two seasons. Twenty infested or noninfested berries in separate cages (250 ml plastic cups) were placed on the plants or on the ground under the tree canopy, in each field. The number of infested berries and CBB females that emerged from the infested berries were recorded weekly. CBB emergence was higher from berries on the ground than those on the coffee trees in both seasons, whereas CBB infestation was higher on coffee berries on the plants than those on the ground in season I. Insolation (hours of sunlight) and temperature were the main covariates that affected emergence and infestation by this insect. The results are discussed for monitoring CBB during the time of dispersal with implications on integrated management of this pest.


Assuntos
Coffea , Dinâmica Populacional , Gorgulhos/crescimento & desenvolvimento , Animais , Clima , Produtos Agrícolas , Monitorização de Parâmetros Ecológicos , Análise Fatorial , Controle de Pragas , Plantas , Sementes , Luz Solar , Temperatura , Gorgulhos/fisiologia
7.
An Acad Bras Cienc ; 92 Suppl 1: e20180477, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32491140

RESUMO

Anticarsia gemmatalis Hübner, 1818 (Lepidoptera) is a major pest of soybean in the Brazil. It is known that the reduction of proteolytic activity by the ingestion of protease inhibitors reduces digestion and larval development of the insects. Control via inhibition of the digestive enzymes necessitates deeper knowledge of the enzyme kinetics and the characterization of the inhibition kinetics of these proteases, for better understanding of the active centers and action mechanisms of this enzyme. Trypsin-like proteases found in the gut of Anticarsia gemmatalis were purified in a p-aminobenzamidine agarose column. Kinetic characterization showed KM 0.503 mM for the L-BApNA substrate; Vmax= 46.650 nM s-1; Vmax/[E]= 9.256 nM s-1 mg L-1 and Vmax/[E]/KM= 18.402 nM s-1 mg L-1 mM. The Ki values for the inhibitors benzamidine, berenil, SKTI and SBBI were 11.2 µM, 32.4 µM, 0.25 nM and 1.4 nM, respectively, and all revealed linear competitive inhibition. The SKTI showed the greatest inhibition, which makes it a promising subject for future research to manufacture peptide mimetic inhibitors.


Assuntos
Trato Gastrointestinal/enzimologia , Lepidópteros/enzimologia , Inibidores de Proteases/farmacologia , Animais , Controle de Insetos/métodos , Cinética , Lepidópteros/crescimento & desenvolvimento
8.
Plant Dis ; 104(2): 414-422, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31841378

RESUMO

The fungus Austropuccinia psidii is a major pathogen of Eucalyptus spp. that damages mainly early-stage leaves. Resistant clones are the most widely used control measure for the rust disease caused by A. psidii. Essential oils produced in the plant-host cells are associated with resistance. However, the chemical characteristics of Eucalyptus leaves at different stages of maturity, associated with resistance or susceptibility to A. psidii, need to be determined. The aims of this study were to characterize the chemical composition of essential oils in Eucalyptus leaves at three developmental stages of clones of three E. urophylla × E. grandis hybrids that exhibit different resistance levels to rust and to identify probable resistance-related compounds from them. The rust severity following inoculation and the quantity and quality of the essential oil extracted by hydrodistillation were determined at the first, third, and fifth leaf stages of the three clones. Identification of the compounds present in the essential oil was determined by gas chromatography coupled with mass spectrometry. No rust was observed on the three leaf stages of the resistant clone or on the fifth leaf stage of the susceptible clones. Limonene was found at high percentages in essential oils from the three leaf stages of the resistant clone and at low percentages in the susceptible clones. In vitro and in vivo tests indicated that low limonene percentages stimulated A. psidii urediniospore germination and were not fungitoxic, whereas high percentages caused complete inhibition of germination and degenerative changes in fungal reproductive structures. The limonene present in Eucalyptus leaves can be considered a chemical compound related to the rust resistance of Eucalyptus spp.


Assuntos
Basidiomycota , Eucalyptus , Limoneno , Doenças das Plantas , Folhas de Planta
9.
An Acad Bras Cienc ; 90(4): 3541-3549, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30184013

RESUMO

The sweet potato is an alternative energy source, but its sustainability depends on efficient water use. The objective of this study was to evaluate sweet potato morpho-physiological characteristics, and water use efficiency (WUE). Irrigation depths of 50, 75, 100, and 125% of crop evapotranspiration (ETc) were applied. The morpho-physiological indicators, WUE, leaf area index (LAI), leaf water potential, leaf temperature, and leaf chlorophyll index (ICF), were evaluated. The WUE of the sweet potato cultivars increased until the 75% water depth of the ETc. The LAI of these cultivars increased with irrigation depth, with higher values at 100% of the ETc. The leaf water potential of the two sweet potato cultivars was lowest with the lower irrigation depth. Leaf temperature was closer to that of ambient temperatures in treatments with greater irrigation depth. The increase of the WUE with the greater accumulation of dry biomass is due to greater CO2 diffusion by stomata. The reduction in the growth of these plants is due to water stress limiting stomatal conductance, transpiration, leaf growth (LAI) and chlorophyll concentration, proportional to soil moisture conditions. The functional relationship between soil moisture and growth is essential to optimize irrigation management at different growth stages.


Assuntos
Irrigação Agrícola/métodos , Ipomoea batatas/crescimento & desenvolvimento , Folhas de Planta/crescimento & desenvolvimento , Estômatos de Plantas/fisiologia
10.
An Acad Bras Cienc ; 90(4): 3625-3633, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30184014

RESUMO

Herbicides can impact non-target metabolic pathways in natural enemies and lead to the reduction of these populations in the field. Behavioral characteristics, morphology and histology of reproductive structures and reproduction of females of Podisus nigrispinus (Dallas) (Hemiptera: Pentatomidae) were evaluated under the effect of the herbicides atrazine, nicosulfuron and the mixture of both. The number of mature oocytes per ovary was lower in females exposed to the herbicides atrazine, nicosulfuron and the mixture of both. Herbicides did not affect the longevity and mortality of P. nigrispinus, therefore, they are selective for this predator. On the other hand, herbicides can cause sublethal effects by affecting the reproduction of predators.


Assuntos
Atrazina/farmacologia , Hemípteros/efeitos dos fármacos , Herbicidas/farmacologia , Piridinas/farmacologia , Compostos de Sulfonilureia/farmacologia , Animais , Atrazina/administração & dosagem , Relação Dose-Resposta a Droga , Feminino , Hemípteros/classificação , Herbicidas/administração & dosagem , Piridinas/administração & dosagem , Reprodução/efeitos dos fármacos , Compostos de Sulfonilureia/administração & dosagem
11.
An Acad Bras Cienc ; 90(4): 3415-3422, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30365711

RESUMO

The response of plants to grazing includes the production of chemical defense compounds such as proteases inhibitors and secondary metabolites as flavonoids, which makes them less palatable to feeding and negatively affecting the physiology of insects. The aim of this study was to evaluate the phytochemical response of soybean cultivars (Glycine max (L.) Merrill) resistant (IAC-17, IAC-24) and susceptible (IAC-P1) to insects after mechanical damage. These cultivars were mechanically injured, and after 24 hours samples of these plants were analyzed by HPLC to identify and quantify flavonoids. The flavonoids daidzein, quercetin, and rutin were quantified, with the highest concentration of daidzin in soybean cultivars after mechanical damage. Rutin was biosynthesized by IAC-24. The cultivars IAC-PL1, IAC-17, and IAC-24 did not show a flavonoid response to mechanical damage. The soybean cultivars are not dependent on mechanical damage to produce flavonoids.


Assuntos
Glycine max/química , Isoflavonas/análise , Folhas de Planta/química , Quercetina/análise , Rutina/análise , Cromatografia Líquida de Alta Pressão , Fenômenos Mecânicos , Fenômenos Fisiológicos Vegetais
12.
An Acad Bras Cienc ; 89(4): 2955-2969, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29236858

RESUMO

The host acceptance behavior and environmental factors as temperature affect the feeding behavior of Lepidoptera pests. Thus, they must be considered in studies about the risk potential of resistance evolution. The current study sets the differences in the feeding behavior of neonate Alabama argillacea (Hübner) (Lepidoptera: Noctuidae) larvae exposed to Bt and non-Bt cotton plants, under different temperatures and time gap after hatching. Two cotton cultivars were used: the Bt (DP 404 BG - bollgard) and the non-transformed isoline, DP 4049. We found that the feeding behavior of neonate A. argillacea is significantly different between Bt and non-Bt cotton. Based on the number of larvae with vegetal tissue in their gut found on the plant and in the organza as well as on the amount of vegetal tissue ingested by the larvae. A. argillacea shows feeding preference for non-Bt cotton plants, in comparison to that on the Bt. However, factors such as temperature and exposure time may affect detection capacity and plant abandonment by the larvae and it results in lower ingestion of vegetal tissue. Such results are relevant to handle the resistance of Bt cotton cultivars to A. argillacea and they also enable determining how the cotton seeds mix will be a feasible handling option to hold back resistance evolution in A. argillacea populations on Bt cotton, when it is compared to other refuge strategies. The results can also be useful to determine which refuge distribution of plants is more effective for handling Bt cotton resistance to A. argillacea.


Assuntos
Comportamento Alimentar/fisiologia , Gossypium/parasitologia , Lepidópteros/fisiologia , Temperatura , Animais , Bioensaio , Gossypium/genética , Lepidópteros/classificação , Controle Biológico de Vetores , Plantas Geneticamente Modificadas
13.
An Acad Bras Cienc ; 89(4): 3083-3092, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29236860

RESUMO

Coffee is one of the most important Brazilian agricultural commodities exported, and Minas Gerais and Espírito Santo States are the main coffee producers. Scale insects are important coffee pests, and 73 species of Cerococcidae (3), Coccidae (18), Diaspididae (6), Eriococcidae (1), Ortheziidae (3), Pseudococcidae (21), Putoidae (2) and Rhizoecidae (19) have been associated with roots, branches, leaves, flowers and fruits of Arabica coffee in the Neotropics. Eight species were found associated with Arabica coffee in Minas Gerais and Espírito Santo States in this study, and Coccidae was the most frequent family. Coccus alpinus, Cc. celatus, Cc. lizeri, Cc. viridis, and Saissetia coffeae (Coccidae) were found in both states; Alecanochiton marquesi, Pseudaonidia trilobitiformis (Diaspididae), and Dysmicoccus texensis (Pseudococcidae) were only found in Minas Gerais. Alecanochiton marquesi and P. trilobitiformis are first reported in Minas Gerais, and Cc. alpinus in Espírito Santo, on Arabica coffee. All scale insect species were associated with coffee leaves and branches, except D. texensis, associated with coffee roots. Fourty seven scale insect species have been found occurring in Brazilian Arabica coffee, and in Espírito Santo (28) and Minas Gerais (23). Widespread and geographical distribution of each species found are discussed.


Assuntos
Café/parasitologia , Hemípteros/fisiologia , Distribuição Animal , Animais , Brasil , Hemípteros/classificação , Dispersão Vegetal , Clima Tropical
14.
J Environ Sci Health B ; 52(1): 70-76, 2017 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-27726483

RESUMO

Selective agrochemicals including herbicides that do not affect non-target organisms such as natural enemies are important in the integrated pest management (IPM) programs. The aim of this study was to evaluate the herbicide toxicity, selectivity and hormesis of nicosulfuron, recommended for the corn Zea mays L. (Poaceae) crop, on 10 Trichogrammatidae (Hymenoptera) species. A female of each Trichogramma spp. or Trichogrammatoidea annulata De Santis, 1972 was individually placed in plastic test tubes (no choice) with a cardboard containing 45 flour moth Anagasta ( = Ephestia) kuehniella Zeller, 1879 (Lepidoptera: Pyralidae) eggs. Parasitism by these natural enemies was allowed for 48 h and the cardboards were sprayed with the herbicide nicosulfuron at 1.50 L.ha-1, along with the control (only distilled water). Nicosulfuron reduced the emergence rate of Trichogramma bruni Nagaraja, 1983 females, but increased that of Trichogramma pretiosum Riley, 1879, Trichogramma acacioi Brun, Moraes and Smith, 1984 and T. annulata females. Conversely, this herbicide increased the emergence rate of Trichogramma brasiliensis Ashmead, 1904, T. bruni, Trichogramma galloi Zucchi, 1988 and Trichogramma soaresi Nagaraja, 1983 males and decreased those of T. acacioi, Trichogramma atopovilia Oatman and Platner, 1983 and T. pretiosum males. In addition, nicosulfuron reduced the sex ratio of T. galloi, Trichogramma bennetti Nagaraja and Nagarkatti, 1973 and T. pretiosum and increased that of T. acacioi, T. bruni, T. annulata, Trichogramma demoraesi Nagaraja, 1983, T. soaresi and T. brasiliensis. The herbicide nicosulfuron was "harmless" (class 1, <30% reduction) for females and the sex ratio of all Trichogrammatidae species based on the International Organization for Biological Control (IOBC) classification. The possible hormesis effect of nicosulfuron on Trichogrammatidae species and on the bacterium Wolbachia sp. (Rickettsiales: Rickettsiaceae) was also discussed.


Assuntos
Herbicidas/toxicidade , Hormese/efeitos dos fármacos , Himenópteros/efeitos dos fármacos , Lepidópteros/parasitologia , Piridinas/toxicidade , Compostos de Sulfonilureia/toxicidade , Animais , Feminino , Lepidópteros/efeitos dos fármacos , Masculino , Mariposas , Óvulo/efeitos dos fármacos , Óvulo/parasitologia , Controle Biológico de Vetores , Razão de Masculinidade
15.
Bull Environ Contam Toxicol ; 99(5): 589-594, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28975358

RESUMO

The aim of this study was to evaluate the effect of the herbicide mixture nicosulfuron + atrazine on 10 trichogrammatid species. A female of each trichogrammatid was placed in a test tube (no-choice) with a card with 45 Anagasta kuehniella eggs. Parasitism was allowed over a 48 h period, then the cards were sprayed with a solution containing nicosulfuron (30 g ha-1) + atrazine (1500 g ha-1), besides the control (distilled water). The nicosulfuron + atrazine mixture increased the Trichogramma atopovirilia and T. pretiosum female emergence. The percentage of T. acacioi, T. atopovilia and T. pretiosum male parasitoids emerged was higher in the control, and for T. demoraesi and Trichogrammatoidea annulata with nicosulfuron + atrazine. Sex ratio of the trichogrammatids was similar with nicosulfuron + atrazine.


Assuntos
Atrazina/toxicidade , Herbicidas/toxicidade , Hormese/efeitos dos fármacos , Himenópteros/fisiologia , Piridinas/toxicidade , Compostos de Sulfonilureia/toxicidade , Testes de Toxicidade , Animais , Ovos , Feminino , Himenópteros/efeitos dos fármacos , Masculino , Controle Biológico de Vetores , Fatores Sexuais , Razão de Masculinidade
16.
An Acad Bras Cienc ; 87(4): 2091-5, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26536850

RESUMO

This paper records the first report of Megastigmus transvaalensis Hussey (Hymenoptera: Torymidae) in Brazilian peppertree, Schinus terebinthifolius Raddi (Anacardiaceae) drupes in Sorocaba, state of São Paulo, Brazil. This wasp is an invasive species and was found damaging S. terebinthifolius drupes in urban areas (35.0 ± 15.8%), natural forests (21.5 ± 10.2%) and restoration areas (15.8 ± 8.4%). The bio-ecology and damage caused by M. transvaalensis in the S. terebinthifolius drupes warrants further study focused upon the management of this phytophagous wasp. Megastigmus transvaalensis has a potential to be disseminated throughout Brazil and is posing a threat to the natural regeneration of S. terebinthifolius in the native forests and restoration areas and ecological regions of this country.


Assuntos
Anacardiaceae/parasitologia , Vespas/fisiologia , Anacardiaceae/classificação , Animais , Comportamento Animal , Feminino , Masculino , Vespas/classificação
17.
Microsc Microanal ; 21(6): 1514-1522, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26601683

RESUMO

Podisus distinctus (Hemiptera: Pentatomidae) is a zoophytophagous insect with significant potential for use as a biological control agent in agriculture and forestry because their nymphs and adults actively prey on diverse insect species. The saliva of this insect possesses active substances that cause paralysis and death of the prey. As the first step in identifying compounds of P. distinctus saliva, this study describes the ultrastructure of the salivary glands of this predator. The salivary system of P. distinctus possesses a pair of main salivary glands with a short anterior lobe, a long posterior lobe, and a pair of tubular accessory glands. The main salivary gland of P. distinctus has no associated muscles, suggesting that the saliva-release mechanism occurs with the help of certain thorax muscles. The main salivary gland epithelium has a single layer of cells (varying from cubical to columnar) with cytoplasm rich in rough endoplasmic reticulum, spherical granules of different sizes, a nucleus with a predominance of decondensed chromatin, and nucleolus. The apical cell region has a few short microvilli and the basal region has plasma membrane infoldings. The epithelium of the accessory salivary glands possesses a single-layered epithelium of cubic cells delimiting a narrow lumen. The apical cell region has a high density of microvilli and pleomorphic mitochondria, whereas the central cell region is rich in rough endoplasmic reticulum with a well-developed nucleus and decondensed chromatin. The basal cell region is characterized by the presence of several basal plasma membrane infoldings associated with mitochondria and numerous openings to the hemocoel forming large channels. The ultrastructural characteristics suggest that the main salivary glands and accessory salivary glands play a vital role in protein synthesis for saliva production and that the accessory glands are involved in transport of materials of the hemolymph.

18.
J Econ Entomol ; 108(3): 1124-8, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26470237

RESUMO

Genus Atta includes some of the most important Formicidae leaf cutter ants which cause extensive damage to the eucalyptus plantations. Atta sexdens rubropilosa Forel, one of the chief pests in Brazilian reforestation, can restrict and reduce forest productivity by its intense and constant leaf-cutting activities on plants at all stages. Therefore, the demand for new products to control A. sexdens rubropilosa indicates the study of the utilization of the dry powder formulation of diatomaceous earth (DE) against this pest in the eucalyptus cultivars. The study was conducted using 120 colonies of A. sexdens rubropilosa in Eucalyptus grandis Hill ex. Maiden x Eucalyptus urophylla Blake (Myrtaceae) (urograndis) stand. The randomized block experimental design was used with six treatments (1, 10, 25, and 50 g/m2 of DE, 6.0 g/m2 sulfluramid bait per square meter of loose soil, and the control) with five replications, each with four colonies of this ant. Diatomaceous earth was applied to the active A. sexdens rubropilosa ant holes, and the sulfluramid bait was applied in bulk in a localized manner. The control efficacy of A. sexdens rubropilosa with DE was low, showing values similar to that of the control, and, for this reason, it cannot be used to control this ant. The bait with sulfluramid showed higher efficacy than those of the other treatments.


Assuntos
Formigas , Terra de Diatomáceas , Eucalyptus/crescimento & desenvolvimento , Agricultura Florestal , Controle de Insetos , Animais , Brasil
19.
J Insect Sci ; 152015.
Artigo em Inglês | MEDLINE | ID: mdl-25843587

RESUMO

Demotispa neivai Bondar (Coleoptera: Chrysomelidae) damage oil palm fruits, which makes it necessary to develop products to control this insect. The mortality, repellency, and antifeeding effects on adults of D. neivai of six plant extracts of Azadirachta indica A. Juss. (Sapindales: Meliaceae), Ricinus communis (L.) (Malpighiaes: Euphorbiaceae), Citrus sinensis Oesbek (Sapindales: Rutaceae), Nicotiana tabacum (L.) (Slanales: Solanaceae), Capsicum annuum (L.) (Solanales: Solanaceae), and Artemisia absinthium (L.) (Asterales: Asteraceae) were determined: 1) the lethal concentration LC50-90, lethal time of D. neivai was evaluated after spraying the fruits of oil palm; 2) repellent effects of each ingredient were evaluated by calculating the index of repellency; 3) antifeeding effects with the rate of inhibition calculated between doses of 20 and 24 g/liter. The mortality of D. neivai was higher with the extracts Ci. sinensis, R. communis, N. tabacum, and Ca. annuum. The mortality of D. neivai increased in the first 72 hr in all treatments. The extracts of N. tabacum, Ca. annuum, and A. indica were more repellent to D. neivai that those of Ci. sinensis, Ar. Absinthium, and R. communis. Antifeeding effect was higher with Ci. sinensis and R. communis. The increased mortality of D. neivai by Ci. sinensis can be explained by the effect of this compound on the respiratory system of insects. Extracts of Ci. sinensis, R. communis, N. tabacum, and Ca. annuum repelled and caused mortality of D. neivai and, thus, can be used in integrate pest management programs of this pest in oil palm plantations.


Assuntos
Besouros , Controle de Insetos , Inseticidas , Extratos Vegetais , Animais , Feminino , Magnoliopsida/química , Masculino
20.
Neotrop Entomol ; 53(1): 175-179, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38032477

RESUMO

This is the first report of Antiteuchus tripterus (Fabricius, 1787) (Heteroptera: Pentatomidae) damaging Araucaria angustifolia (Bertol.) Kuntze, 1898 (Pinales: Araucariaceae) plants in Brazil. This bug, native to the neotropical region, damaged this plant on fragments of mixed rain forest in Bueno Brandão, Minas Gerais state, Brazil. Araucaria angustifolia, native and with ecological and economic values, was widely used in the lumber market and, therefore, threatened with extinction. Nymphs and adults of A. tripterus were observed in March and April with a population reduction until June 2022. The bioecology and damage caused by A. tripterus on A. angustifolia are not known.


Assuntos
Araucaria , Heterópteros , Animais , Brasil , Ninfa , Dinâmica Populacional
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