10 research outputs found
Efectos secundarios sobre Trichogramma atopovirilia Oatman & Platner (Hymenoptera: Trichogramatidae) de fungicidas usados en cucurbitáceas
Trichogramma spp. (Hymenoptera: Trichogrammatidae) can control
Diaphania hyalinata Linnaeus (Lepidoptera: Pyralidae). On the other
hand, pesticides may reduce the efficiency of natural enemies. The
objective was to evaluate the side-effects of fungicides used in the
production of cucurbitaceous crops on Trichogramma atopovirilia
Oatman & Plainer parasitizing D. hyalinata eggs. The fungicides
used in bioassays were: azoxystrobin (0.08 g active ingredient [ai] L
-1 ), chlorothalonil (2.00 g ai L -1 ), mancozeb (1.60 g ai L -1 ),
tebuconazole (0.25 g ai L -1 ) and thiophanate-methyl (0.49 g ai L -1
). Cardboards with 30 D. hyalinata eggs previously immersed in
fungicide solutions and distilled water (control) were offered
separately to 20 newly emerged T. atopovirilia females in glass tubes.
Parasitism, parasitism reduction, emergence, sex ratio, and number of
individuals per egg were evaluated. The fungicides chlorothalonil,
thiophanate-methyl and tebuconazole reduced parasitism of T.
atopovirilia by 43.37, 27.64 and 18.51 %, respectively. However,
parasitism with azoxystrobin (79.21%) was higher than the control
(67.37%) (P ≤ 0.05). Chlorothalonil, thiophanate-methyl and
tebuconazole reduced emergence by 73.77, 75.62 and 79.35% (P ≤
0.05), respectively. Azoxystrobin and thiophanate-methyl reduced the
sex ratio by 0.77 and 0.76 (P ≤ 0.05), respectively. Fungicides
did not reduce the number of individuals per egg. The fungicides
azoxystrobin and mancozeb were selective for T. atopovirilia for most
studied parameters suggesting that these products must have the
priority in crop disease management to allow efficient biological
control of T. atopovirilia against D. hyalinata.Trichogramma spp. (Hymenoptera: Trichogrammatidae) pueden controlar
Diaphania hyalinata Linnaeus (Lepidoptera: Pyralidae). Sin embargo,
los plaguicidas pueden reducir la eficiencia de los enemigos naturales.
El objetivo de este trabajo fue evaluar la influencia de los fungicidas
utilizados en la producción de cucurbitáceas en Trichogramma
atopovirilia Oatman & Platner sobre huevos de D. hyalinata. Se
evaluaron los fungicidas azoxystrobina (0.08 g ingrediente activo [ia]
L-1 ), clorotalonil (2.00 g ia L-1 ), mancozeb (1.60 g ia L-1 ),
tebuconazole (0.25 g ia L-1 ) and tiofanato-metil (0.49 g ia L-1 ).
Tarjetas con 30 huevos de D. hyalinata previamente sumergidos en los
fungicidas y en agua destilada (control) fueron ofrecidas a 20 hembras
de T. atopovirilia con hasta 24 h de emergencia individualizadas en
tubos de vidrio. Se evaluó parasitismo, reducción de
parasitismo, emergencia, proporción sexual en la población y
el número de individuos emergidos por huevo. Los fungicidas
clorotalonil, tiofanato-metil y tebuconazol redujeron el parasitismo de
T. atopovirilia en 43,37; 27,64 y 18,51%, respectivamente. Sin embargo,
el parasitismo con azoxistrobina (79,21%) fue mayor que el control
(67,37%) (P ≤ 0,05). Clorotalonil, tiofanato-metilo y el
tebuconazol redujo la aparición de 73,77, 75,62 y 79,35% (P
≤ 0,05), respectivamente. Azoxistrobina y tiofanato-metil
reduciran la proporción de sexos de 0,77 y 0,76 (P ≤ 0,05),
respectivamente. Ninguno de los fungicidas redujo el número de
individuos por cada huevo. Los fungicidas azoxistrobina y mancozeb
fueron selectivos para T. atopovirilia en la mayoría de los
parámetros estudiados, por lo tanto, deberían tener prioridad
en el manejo de enfermedades de cucurbitáceas para permitir el uso
eficiente de los enemigos naturales de D. hyalinata
Ocorrência de Trichospilus diatraeae (Hym.: Eulophidae) em broca-das-cucurbitáceas, no Brasil
Este trabalho tem como objetivo registrar a primeira ocorrência, no Brasil, do parasitóide de pupas Trichospilus diatraeae (Cherian & Margabandhu, 1942) (Hymenoptera: Eulophidae) na broca-das-cucurbitáceas, Diaphania hyalinata (L.) (Lepidoptera: Pyralidae). A espécie T. diatraeae já foi relatada no Brasil em pragas da gravioleira no Distrito Federal e eucalipto nos estados de Minas Gerais e São Paulo. No sistema produtivo da abóbora D. hyalinata é reconhecidamente uma praga importante por causar sérios prejuízos em função das injúrias provocadas em diferentes partes da planta. A ocorrência do parasitóide foi registrada em pupas coletadas no campo, localizado no campus experimental do Centro de Ciências Agrárias da Universidade Federal do Espírito Santo (UFES), no município de Alegre-ES.This study aims to record the first occurrence in Brazil of the parasitoid pupae Trichospilus diatraeae (Cherian & Margabandhu, 1942) (Hymenoptera: Eulophidae) on the melonworm, Diaphania hyalinata (L.) (Lepidoptera: Pyralidae). The specie T. diatraeae has been reported in pests of the soursop in the Distrito Federal, Brazil and eucalyptus in the Brazilian States of Minas Gerais and São Paulo. In the production system of pumpkin D. hyalinata is recognized as a significant pest which causes serious losses as a result of injuries caused in different parts of the plant. The occurrence of the parasitoid was recorded in pupae collected in the field, located on the campus of the Center of Agrarian Sciences, Federal University of Espirito Santo, Alegre Espirito Santo State, Brazil
Desenvolvimento da broca-das-cucurbitáceas em diferentes tipos de substratos alimentares Development of melonworm on different feeding substrates
Aspectos biológicos de Diaphania nitidalis foram estudados sob dietas natural e artificial em condições de laboratório, à temperatura de 25±1ºC, umidade relativa de 70±10% e fotofase de 14 horas. Como dieta natural foi utilizada abóbora 'Jacaré', pepino 'Japonês' e abobrinha 'Caserta' e, como artificial, a dieta utilizada em criações de Diatraea saccharalis, broca da cana-de-açúcar. As lagartas de D. nitidalis foram inoculadas nos diferentes tipos de substratos e criadas por todo o ciclo. Ocorreu diferença significativa entre a maioria dos parâmetros testados dentro dos tratamentos, sendo as dietas à base de abóbora e artificial as que proporcionaram maior potencial biótico para criação de D. nitidalis. Pela facilidade de aquisição dos ingredientes e manipulação dos insetos, a dieta artificial se torna mais eficaz para criação massal dessa espécie em laboratório.<br>The aim of this research was to evaluate the biological behaviour of melonworm at different natural and artificial diet under laboratory conditions (25ºC, 70% RH, 14 h photofase). Squash 'Jacaré', cucumber 'Japonês' and zucchini 'Caserta' were used as natural substrates compared to na artificial diet developed for the sugarcane borer (Diatraea saccharalis). The caterpillars were inoculated in each substrate and reared for a full cycle. The biological parameters were different among treatments. An artificial diet and squash cv. Jacaré substrate showed higher performance for the multiplication of D. nitidalis. The artificial diet is recommended because it is easy to obtain the ingredients and nultiply this insect under laboratory conditions
Avaliação de Trichogramma spp. para o controle de Trichoplusia ni Evaluation of Trichogramma spp. for the control of Trichoplusia ni
O objetivo deste trabalho foi avaliar as características biológicas dos parasitoides Trichogramma acacioi, T. atopovirilia, T. marandobai, T. demoraesi, T. exiguum (duas linhagens) e T. pretiosum (seis linhagens), criados em ovos de Trichoplusia ni. O experimento foi conduzido em delineamento inteiramente casualizado, com 15 repetições. As características biológicas avaliadas foram: parasitismo, viabilidade, razão sexual e número de indivíduos por ovo. A percentagem de parasitismo variou entre 7,66 e 53%, com maior valor observado para a linhagem Tspd de Trichogramma pretiosum, e o menor para a linhagem Trecife de T. pretiosum. Não houve diferença significativa dessa espécie quanto à viabilidade, que ficou acima de 85%. A razão sexual variou de 0,75 a 1, e a linhagem Tspd apresentou o menor valor. O número de parasitoides por ovo variou entre 2,39 para T. marandobai (linhagem Tm1) e 1,34 para T. exiguum (linhagem Te1). A espécie que apresentou o melhor desempenho em laboratório foi T. pretiosum (Tspd), com os maiores valores observados na percentagem de parasitismo e na emergência.<br>The objective of this study was to evaluate the biological characteristics of the parasitoids Trichogramma acacioi, T. atopovirilia, T. marandobai, T. demoraesi, T. exiguum (two lines), and T. pretiosum (six lines), reared on eggs of Trichoplusia ni. The experiment was carried out in a completely randomized design, with 15 replicates. The biological characteristics evaluated were: parasitism, viability, sexual ratio and number of individuals per egg. The parasitism percentage varied between 7.66 and 53%, whith highest value observed for Trichogramma pretiosum Tspd line, and the lowest for the T. pretiosum Trecife line. There was no significant difference for the viability, which remained higher than 85%. The sex ratio varied from 0.75 to 1, and Tspd line showed the lowest value. The number of individuals per egg varied between 2.39 for T. marandobai (Tm1 line) and 1.34 for T. exiguum (Te1 line). T. pretiosum (Tspd line) was the species with the best performance in laboratory with the highest values observed in parasitism and in viability
Serum Metabolic Alterations upon Zika Infection
Zika virus (ZIKV) infection has recently emerged as a major concern worldwide due to its strong association with nervous system malformation (microcephaly) of fetuses in pregnant women infected by the virus. Signs and symptoms of ZIKV infection are often mistaken with other common viral infections. Since transmission may occur through biological fluids exchange and coitus, in addition to mosquito bite, this condition is an important infectious disease. Thus, understanding the mechanism of viral infection has become an important research focus, as well as providing potential targets for assertive clinical diagnosis and quality screening for hemoderivatives. Within this context, the present work analyzed blood plasma from 79 subjects, divided as a control group and a ZIKV-infected group. Samples underwent direct-infusion mass spectrometry and statistical analysis, where eight markers related to the pathophysiological process of ZIKV infection were elected and characterized. Among these, Angiotensin (1-7) and Angiotensin I were upregulated under infection, showing an attempt to induce autophagy of the infected cells. However, this finding is concerning about hypertensive individuals under treatment with inhibitors of the Renin-Angiotensin System (RAS), which could reduce this response against the virus and exacerbate the symptoms of the infection. Moreover, one of the most abundant glycosphingolipids in the nervous tissue, Ganglioside GM2, was also elected in the present study as an infection biomarker. Considered an important pathogen receptor at membrane's outer layer, this finding represents the importance of gangliosides for ZIKV infection and its association with brain tropism. Furthermore, a series of phosphatidylinositols were also identified as biomarkers, implying a significant role of the PI3K-AKT-mTOR Pathway in this mechanism. Finally, these pathways may also be understood as potential targets to be considered in pharmacological intervention studies on ZIKV infection management
Gas6 drives Zika virus-induced neurological complications in humans and congenital syndrome in immunocompetent mice
Zika virus (ZIKV) has the ability to cross placental and brain barriers, causing congenital malformations in neonates and neurological disorders in adults. However, the pathogenic mechanisms of ZIKV-induced neurological complications in adults and congenital malformations are still not fully understood. Gas6 is a soluble TAM receptor ligand able to promote flavivirus internalization and downregulation of immune responses. Here we demonstrate that there is a correlation between ZIKV neurological complications with higher Gas6 levels and the downregulation of genes associated with anti-viral response, as type I IFN due to Socs1 upregulation. Also, Gas6 gamma-carboxylation is essential for ZIKV invasion and replication in monocytes, the main source of this protein, which was inhibited by warfarin. Conversely, Gas6 facilitates ZIKV replication in adult immunocompetent mice and enabled susceptibility to transplacental infection. Our data indicate that ZIKV promotes the upregulation of its ligand Gas6, which contributes to viral infectivity and drives the development of severe adverse outcomes during ZIKV infection