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1.
Braz J Biol ; 83: e267598, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37283334

RESUMO

Plant-induced resistance can be an important component of soybean mites biological control programs. This work evaluates the preference of predatory mite Neoseiulus californicus (Acari: Phytoseiidae) to soybean plants under single and multiple herbivory conditions by two-spotted spider mite Tetranychus urticae (Acari: Tetranychidae), and velvetbean caterpillar Anticarsia gemmatalis (Lepidoptera: Noctuidae). Using a Y olfactometer, the following scenarios were evaluated: soybean with no infestation and soybean infested with A. gemmatalis; soybean infested with T. urticae and A. gemmatalis, and soybean infested with T. urticae and with both T. urticae and A. gemmatalis. Volatile compounds released by plants were analyzed and identified by a Trace GC Ultra gas chromatograph coupled to a mass spectrometer with a solid phase micro-extraction ion-trap. The predatory mite N. californicus preferred soybean plants infested with T. urticae compared to those infested with A. gemmatalis. Multiple infestation did not interfere with its preference to T. urticae. Multiple herbivory of T. urticae and A. gemmatalis modified the chemical profile of volatile compounds emitted by soybean plants. However, it did not interfere with the search behavior of N. californicus. Out of the 29 identified compounds only five promoted predatory mite response. Thus, regardless of single or multiple herbivory by T. urticae with or without A. gemmatalis, the indirect induced resistance mechanisms operate similarly. As such, this mechanism contributes to an increase in the encounter rate between predator and prey for N. Californicus and T. urticae, and the efficacy of biological control of mites on soybean.


Assuntos
Glycine max , Glycine max/química , Compostos Orgânicos Voláteis/química , Herbivoria , Comportamento Predatório , Animais , Ácaros
2.
Bull Entomol Res ; : 1-14, 2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34130764

RESUMO

Plants not only respond to herbivorous damage but adjust their defense system after egg deposition by pest insects. Thereby, parasitoids use oviposition-induced plant volatiles to locate their hosts. We investigated the olfactory behavioral responses of Trichogramma pretiosum Riley, 1879 (Hymenoptera: Trichogrammatidae) to volatile blends emitted by maize (Zea mays L.) with singular and stacked events after oviposition by Spodoptera frugiperda Smith, 1797 (Hymenoptera: Trichogrammatidae) moths. Additionally, we examined possible variations in gene expression and on oviposition-induced volatiles. We used a Y-tube olfactometer to test for the wasp responses to volatiles released by maize plants oviposited by S. frugiperda and not-oviposited plants. Using the real-time PCR technique (qRT-PCR), we analyzed the expression of lipoxygenase and three terpene synthases genes, which are enzymes involved in the synthesis of volatile compounds that attract parasitoids of S. frugiperda. Olfactometer tests showed that T. pretiosum is strongly attracted by volatiles from transgenic maize emitted by S. frugiperda oviposition (VTPRO 3, more than 75% individuals were attracted). The relative expression of genes TPS10, LOX e STC was higher in transgenic hybrids than in the conventional (isogenic line) hybrids. The GC-MS analysis revealed that some volatile compounds are released exclusively by transgenic maize. This study provides evidence that transgenic hybrids enhanced chemical cues under oviposition-induction and helped to increase T. pretiosum efficiency in S. frugiperda control. This finding shows that among the evaluated hybrids, genetically modified hybrids can improve the biological control programs, since they potentialize the egg parasitoid foraging, integrating pest management.

3.
Trop Biomed ; 37(2): 513-535, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33235398

RESUMO

After a centenary fight against malaria, Brazil has seen an opportunity for change with the proposal of the malaria elimination policy set by the Brazilian government, in line with malaria elimination policies in other Latin American countries. Brazilian malaria experts regard eliminating malaria by 2030 to be within reach. Herein we evaluated the likelihood that malaria elimination can be accomplished in Brazil through systematic review of the literature on malaria elimination in Brazil and epidemiological analysis. Fifty-two articles referring to malaria eradication/elimination in Brazil were analyzed to identify challenges and technological breakthroughs for controlling malaria. Monthly deaths (1979-2016) and monthly severe malaria cases (1998-2018) were analyzed according to age groups, geographic region and parasite species. As a result, we observed that the declining malaria burden was mostly attributable to a decline in Plasmodium falciparum-malaria. At the same time, the proportional increase of Plasmodium vivax-malaria in comparison with P. falciparum-malaria was notable. This niche replacement mechanism was discussed in the reviewed literature. In addition, the challenges to P. vivax-malaria elimination outnumbered the available technological breakthroughs. Although accumulated and basic information exists on mosquito vector biology, the lack of specific knowledge about mosquito vector taxonomy and ecology may hamper current attempts at stopping malaria in the country. An impressive reduction in malaria hospitalizations and mortality was seen in Brazil in the past 3 decades. Eliminating malaria deaths in children less than 5 years and P. falciparum severe cases may be achievable goals under the current malaria policy until 2030. However, eliminating P. vivax malaria transmission and morbidity seems unattainable with the available tools. Therefore, complete malaria elimination in Brazil in the near future is unlikely.


Assuntos
Antimaláricos/uso terapêutico , Malária Falciparum/epidemiologia , Malária Vivax/epidemiologia , Malária/epidemiologia , Brasil/epidemiologia , Erradicação de Doenças , Humanos , Malária/parasitologia , Malária/prevenção & controle , Malária Falciparum/parasitologia , Malária Falciparum/prevenção & controle , Malária Vivax/parasitologia , Malária Vivax/prevenção & controle , Políticas
4.
Tropical Biomedicine ; : 513-535, 2020.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-823262

RESUMO

@#After a centenary fight against malaria, Brazil has seen an opportunity for change with the proposal of the malaria elimination policy set by the Brazilian government, in line with malaria elimination policies in other Latin American countries. Brazilian malaria experts regard eliminating malaria by 2030 to be within reach. Herein we evaluated the likelihood that malaria elimination can be accomplished in Brazil through systematic review of the literature on malaria elimination in Brazil and epidemiological analysis. Fifty-two articles referring to malaria eradication/elimination in Brazil were analyzed to identify challenges and technological breakthroughs for controlling malaria. Monthly deaths (1979–2016) and monthly severe malaria cases (1998–2018) were analyzed according to age groups, geographic region and parasite species. As a result, we observed that the declining malaria burden was mostly attributable to a decline in Plasmodium falciparum-malaria. At the same time, the proportional increase of Plasmodium vivax-malaria in comparison with P. falciparum-malaria was notable. This niche replacement mechanism was discussed in the reviewed literature. In addition, the challenges to P. vivax-malaria elimination outnumbered the available technological breakthroughs. Although accumulated and basic information exists on mosquito vector biology, the lack of specific knowledge about mosquito vector taxonomy and ecology may hamper current attempts at stopping malaria in the country. An impressive reduction in malaria hospitalizations and mortality was seen in Brazil in the past 3 decades. Eliminating malaria deaths in children less than 5 years and P. falciparum severe cases may be achievable goals under the current malaria policy until 2030. However, eliminating P. vivax malaria transmission and morbidity seems unattainable with the available tools. Therefore, complete malaria elimination in Brazil in the near future is unlikely.

5.
Genet Mol Res ; 13(2): 2691-7, 2014 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-24782082

RESUMO

This study aimed to evaluate the chemical composition of the essential oils from three genotypes of Lippia gracilis Schauer (Verbenaceae) and investigate the cytotoxic activities of these oils. Essential oils were extracted from the leaves using a Clevenger-type apparatus, and chemical analysis was performed using a gas chromatograph coupled to a mass spectrometer and flame ionization detector. 3T3, MRC5, B16, HeLa, and MCF-7 cell lines were used to study the in vitro cytotoxicity of the essential oils, and the level of cell death was determined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide test with three replicates. The cytotoxic activity was expressed as the concentration that inhibited 50% of cell growth. The main compound in the essential oil of LGRA-106 was thymol (40.52%), while LGRA-109 and LGRA-201 contained 45.84 and 32.60% carvacrol, respectively, as their major compound. The essential oils of L. gracilis showed cytotoxic activity against both normal and tumor cells at concentrations below 100 µg/mL; this demonstrated the antitumor potential of these essential oils, which should be further investigated.


Assuntos
Proliferação de Células/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Lippia/química , Células HeLa , Humanos , Células MCF-7 , Óleos Voláteis/administração & dosagem , Óleos Voláteis/química , Óleos de Plantas/administração & dosagem , Óleos de Plantas/química
6.
Genet Mol Res ; 11(3): 1949-57, 2012 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-22869550

RESUMO

Aluminum (Al) toxicity restricts root growth and agricultural yield in acid soils, which constitute approximately 40% of the potentially arable lands worldwide. The two main mechanisms of Al tolerance in plants are internal detoxification of Al and its exclusion from root cells. Genes encoding membrane transporters and accessory transcription factors, as well as cis-elements that enhance gene expression, are involved in Al tolerance in plants; thus studies of these genes and accessory factors should be the focus of molecular breeding efforts aimed at improving Al tolerance in crops. In this review, we describe the main genetic and molecular studies that led to the identification and cloning of genes associated with Al tolerance in plants. We include recent findings on the regulation of genes associated with Al tolerance. Understanding the genetic, molecular, and physiological aspects of Al tolerance in plants is important for generating cultivars adapted to acid soils, thereby contributing to food security worldwide.


Assuntos
Adaptação Fisiológica/efeitos dos fármacos , Adaptação Fisiológica/genética , Alumínio/toxicidade , Plantas/efeitos dos fármacos , Plantas/genética , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas/genética
7.
Rev. bras. plantas med ; 13(1): 17-23, 2011. ilus, tab
Artigo em Português | LILACS | ID: lil-582757

RESUMO

Coriandrum sativum L. (Umbelliferae), conhecido popularmente por coentro, é uma planta doméstica cultivada nas diversas partes do mundo, inclusive no Brasil. As folhas e frutos do coentro são utilizados como condimento em culinária e na medicina popular como analgésica, antirreumática, carminativa e colagoga. O objetivo deste estudo foi avaliar o efeito do tratamento com o óleo essencial (OEC) e o extrato hidroalcóolico (EHC) do coentro em modelos experimentais de inflamação em roedores. A atividade antiinflamatória do coentro foi avaliada por meio dos testes de pleurisia em ratos e formação do edema de orelha em camundongos. A pleurisia foi induzida pela carragenina em animais tratados ou não com EHC. O edema de orelha induzido pela aplicação tópica de óleo de cróton e a atividade da mieloperoxidase foi avaliada em camundongos tratados ou não com OEC ou EHC. No teste da pleurisia o tratamento com EHC promoveu significativa diminuição no edema pleural, mas não sobre a migração leucocitária. Além disso, diferentemente ao observado com o tratamento com OEC, o uso tópico de EHC diminui significativamente o edema de orelha e a migração celular induzidos pela aplicação do óleo de cróton. Os dados indicam que EHC apresenta atividade antiinflamatória quando administrado pelas via oral e tópica, enquanto que OEC não apresenta atividade antiinflamatória tópica.


Commonly known as coriander, Coriandrum sativum L. (Umbelliferae) is a home plant grown in several parts of the world, including Brazil. Its leaves and fruits have been used as condiment in cooking and in folk medicine as analgesic, antirheumatic, carminative and cholagogue. The aim of this study was to evaluate the effect of essential oil (EO) and hydroalcoholic extract (HE) from coriander on experimental inflammation models in rodents. Coriander anti-inflammatory activity was evaluated by pleurisy tests in rats and ear edema formation in mice. Pleurisy was induced by carrageenan in HE-treated or non-treated animals. The ear edema was induced by topical application of croton oil and the myeloperoxidase activity was evaluated in EO-treated and HE-treated or non-treated mice. In the pleurisy test, HE treatment significantly decreased pleural edema but not the leukocyte migration. Furthermore, differently from EO, the topical use of HE significantly decreased ear edema and cell migration induced by croton oil application. The results indicate that HE had anti-inflammatory activity when orally and topically administered, whereas EO did not present topical anti-inflammatory activity.


Assuntos
Animais , Masculino , Adulto Jovem , Camundongos , Ratos , Anti-Inflamatórios , Coriandrum , Análise de Variância , Orelha , Edema , Inflamação , Plantas Medicinais , Pleurisia/prevenção & controle
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