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1.
Zootaxa ; 4455(1): 161-176, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30314225

RESUMO

Arma custos and A. chinensis have a very conspicuous difference in the shape of the pronotal humeral angle, but the genitalic morphological characters are ambiguous and difficult to recognize. The aim of this study was to analyze the taxonomic status of A. chinensis and A. custos based on morphological, molecular, and geographical evidence, and to determine whether DNA barcoding could be a useful additional tool for differentiating similar species. The results clearly demonstrate that A. custos and A. chinensis have not diverged into separate species. So, the following new synonym is proposed: Arma chinensis Fallou, 1881 = Arma custos (Fabricius, 1794) syn. nov.. The results also showed that DNA barcoding using the marker COI can resolve insect taxonomic problems.

2.
J Insect Sci ; 18(2)2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29718506

RESUMO

Dinorhynchus dybowskyi (Hemiptera: Pentatomidae: Asopinae) is used as a biological control agent against various insect pests for its predatory. In the present study, the complete mitochondrial genome (mitogenome) of the species was sequenced using the next-generation sequencing technology. The results showed that the mitogenome is 15,952 bp long, including 13 protein-coding genes (PCGs), 22 transfer RNAs (tRNAs), two ribosomal RNAs (rRNAs), and a control region. Furthermore, the gene order and orientation of this mitogenome are identical to those of most heteropterans. There are 21 intergenic spacers (of length 1-28 bp) and 13 overlapping regions (of length 1-23 bp) throughout the genome. The control region is 1,291 bp long. The start codon of the PCGs is ATN, except cox1 (TTG), and stop codon is TAA, except nad1 (TAG). The 22 tRNAs exhibit a typical cloverleaf secondary structure, except trnS1, which lacks a dihydrouridine (DHU) arm and trnV, where the DHU arm forms a simple loop. The analyses based on nucleotide sequences of the 13 PCGs by Bayesian Inference and maximum likelihood methods. The results support the monophyly of five superfamilies Aradoidea, Pentatomoidea, Pyrrhocoroidea, Lygaeoidea, and Coreoidea. Within Pentatomoidea, the relationship observed is as follows: (Plataspidae + Urostylididae) + (Pentatomidae + (Acanthosomatidae + (Cydnidae + (Scutelleridae + (Dinidoridae + Tessaratomidae))))), and D. dybowskyi was placed in Pentatomidae and close to Eurydema gebleri.


Assuntos
Genoma de Inseto , Genoma Mitocondrial , Hemípteros/genética , Filogenia , Animais , Controle Biológico de Vetores , RNA Ribossômico/genética , RNA de Transferência/genética
3.
PeerJ ; 6: e4832, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29844981

RESUMO

Cycads are an ancient group of gymnosperms that are popular as landscaping plants, though nearly all of them are threatened or endangered in the wild. The cycad aulacaspis scale (CAS), Aulacaspis yasumatsui Takagi (Hemiptera: Diaspididae), has become one of the most serious pests of cycads in recent years; however, the potential distribution range and the management approach for this pest are unclear. A potential risk map of cycad aulacaspis scale was created based on occurrence data under different climatic conditions and topology factors in this study. Furthermore, the future potential distributions of CAS were projected for the periods 2050s and 2070s under three different climate change scenarios (GFDL-CM3, HADGEM2-AO and MIROC5) described in the Special Report on Emissions Scenarios of the IPCC (Intergovernmental Panel on Climate Change). The model suggested high environmental suitability for the continents of Asia and North America, where the species has already been recorded. The potential distribution expansions or reductions were also predicted under different climate change conditions. Temperature of Driest Quarter (Bio9) was the most important factor, explaining 48.1% of the distribution of the species. The results also suggested that highly suitable habitat for CAS would exist in the study area if the mean temperature of 15-20 °C in the driest quarter and a mean temperature of 25-28 °C the wettest quarter. This research provides a theoretical reference framework for developing policy to manage and control this invasive pest.

4.
PLoS One ; 12(7): e0180913, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28700721

RESUMO

The cotton mealybug, Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae), is a serious invasive species that significantly damages plants of approximately 60 families around the world. It is originally from North America and has also been introduced to other continents. Our goals were to create a current and future potential global distribution map for this pest under climate change with MaxEnt software. We tested the hypothesis of niche conservatism for P. solenopsis by comparing its native niche in North America to its invasive niches on other continents using Principal components analyses (PCA) in R. The potentially suitable habitat for P. solenopsis in its native and non-native ranges is presented in the present paper. The results suggested that the mean temperature of the wettest quarter and the mean temperature of the driest quarter are the most important environmental variables determining the potential distribution of P. solenopsis. We found strong evidence for niche shifts in the realized climatic niche of this pest in South America and Australia due to niche unfilling; however, a niche shift in the realized climatic niche of this pest in Eurasian owing to niche expansion.


Assuntos
Mudança Climática , Hemípteros/fisiologia , Animais , Ecossistema , Análise de Componente Principal , Software , Temperatura Ambiente
5.
Zookeys ; (619): 13-24, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27829787

RESUMO

A new species of armored scale insect, Aulacaspis zunyiensissp. n. is described and illustrated from collections on cycads in China. A key to the Aulacaspis species known from China is provided.

6.
FEMS Microbiol Lett ; 343(1): 57-63, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23510033

RESUMO

Arsenic is a toxic metalloid that is widely distributed in the environment, and its toxicity has been demonstrated in several models. However, the mechanism of arsenic toxicity still remains unclear. In this study, the toxic effects of sodium arsenite (1-7 mM) on yeast cells were investigated. The experimental results showed that sodium arsenite inhibited yeast cell growth, and the inhibitory effect of cell growth (OD600 nm values) was positively correlated with arsenite concentrations. Sodium arsenite caused loss of cell viability in a concentration- and duration-dependent manner in yeast cells. However, arsenite-caused cell viability loss was blocked by either antioxidants (200 U mL(-1) CAT and 0.5 mM AsA) or Ca(2+) antagonists (0.5 mM LaCl3 and 0.5 mM EGTA). We also found intracellular reactive oxygen species (ROS) and Ca(2+) levels increased significantly in yeast cells after exposure to 3 mM and 7 mM sodium arsenite for 6 h compared with the control. These results indicated that high concentrations of arsenite-induced yeast cell killing was associated with elevated levels of intracellular ROS and Ca(2+).


Assuntos
Arsenitos/toxicidade , Cálcio/metabolismo , Viabilidade Microbiana/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Saccharomyces cerevisiae/efeitos dos fármacos , Compostos de Sódio/toxicidade , Arsenitos/metabolismo , Cátions Bivalentes/metabolismo , Citosol/química , Compostos de Sódio/metabolismo
7.
Ecotoxicol Environ Saf ; 78: 281-6, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22154778

RESUMO

Sulfur dioxide (SO(2)) induced nuclear condensation and nuclear fragmentation and rapid loss of guard cell viability in detached epidermis of Vicia leaves at concentrations of 1 mM and higher (3 h exposure). Caspase inhibitors Z-Asp-CH(2)-DCB (0.1 mM) and TLCK (0.1 mM) markedly suppressed SO(2)-induced cell death. The typical nuclear morphological changes and the inhibition effects of caspase inhibitors suggest the activation of a programmed cell death (PCD) pathway. SO(2)-induced cell death can be blocked by either antioxidants (0.1 mM AsA or 200 U/mL CAT) or Ca(2+) antagonists (0.1mM EGTA or LaCl(3)). AsA and CAT also blocked SO(2)-induced ROS production and [Ca(2+)](cyt) increase. However, EGTA and LaCl(3) can inhibit SO(2)-induced [Ca(2+)](cyt) increase, but cannot suppress SO(2)-induced ROS production. Our results indicate that high concentrations of SO(2) induce guard cell death via a PCD pathway through ROS mediating [Ca(2+)](cyt) elevation, which causes harmful effects to plants.


Assuntos
Poluentes Atmosféricos/toxicidade , Dióxido de Enxofre/toxicidade , Vicia/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Cálcio/metabolismo , Epiderme Vegetal/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Vicia/fisiologia
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