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Danos de Rhopalosiphum padi (L.) (Hemiptera: Aphididae) no trigo em fun??o da dura??o e da densidade de infesta??o
Roza-Gomes, Margarida F.;Salvadori, José R.;Schons, Jurema;
Neotropical Entomology , 2008, DOI: 10.1590/S1519-566X2008000500013
Abstract: aphids are considered relevant pests on wheat either by direct damage through sap sucking or by indirect damage vectoring bydv (barley yellow dwarf virus). rhopalosiphum padi l. has been observed infesting wheat fields with an increasing frequency. the knowledge and the available technology, besides being more related to other aphids species already recognized as pests, they are insufficient to control the specific problem of r. padi. thus, this work evaluated the effects of feeding duration and infestation densities of r. padi on seedlings of wheat cv. embrapa 16. grain yield, yield components and the extent of symptoms were recorded. the experiment was carried out in the field under a completely randomized split-plot experimental design with four replications. the main plot was feeding duration (two and seven days) and the sub-plots were infestation densities (zero, two and 10 aphids per plant). independent on feeding duration, 10 aphids per plant resulted in significant yield losses, reduction of number of heads and tillers per plant. canopy dry matter was also reduced. infestations of two and 10 aphids per plant resulted in continuous yellowing of wheat plants from tillering to the end of flowering stage. when aphids fed for seven days on wheat, more yellowing symptoms were observed at the flower stage in comparison with two days feeding.
Resposta de cultivares de trigo à infesta??o do pulg?o Rhopalosiphum padi
Peruzzo, Rafael;Salvadori, José Roberto;Pereira, Paulo Roberto Valle da Silva;Bertollo, étel Carmen;Tonello, Lucas Simionatto;
Pesquisa Agropecuária Brasileira , 2007, DOI: 10.1590/S0100-204X2007001200003
Abstract: the objective of this work was to evaluate the response of eight commercial wheat cultivars (brs 194, brs 208, brs camboatá, brs guabiju, brs guamirim, brs louro, brs timbaúva e brs umbu) to the infestation of rhopalosiphum padi (hemiptera: aphididae). the experiment was carried out at embrapa trigo, in greenhouse conditions. it was used the randomized block design, in a split-plot array, with eight treatments and six replicates. the plots received treatments with or without infestation with aphids, and the split-plots were composed by the cultivars. the infestation with aphids (20 wingless adults per plant) was done 12 days after plant emergency, in the beginning of tillering, and was kept for 15 days. the cultivars responded differently to the infestation with aphids. brs timbaúva cultivar is more resistant, and brs umbu and brs guabiju cultivars are more susceptible to r. padi, concerning plant growth and plant yield.
Comparative of feeding behaviors of Sitobion avenae, Sitobion graminum and Rhopalosiphum padi (Homoptera: Aphididae) using electrical penetration graph (EPG)

MIAO Jin,WU Yuqing,YU Zhenxing,DUAN Yun,JIANG Yueli,LI Guoping,

生态学报 , 2011,
Abstract: 麦长管蚜Sitobion avenae (Fabricius),麦二叉蚜Schizaphis graminum (Rondani)和禾谷缢管蚜Rhopalosiphum padi (Linnaeus)虽然都取食小麦,但其取食部位、传毒能力均有差异。利用EPG研究了3种麦蚜在同一寄主植物上的取食行为,结果显示:(1)禾谷缢管蚜在取食过程中G波出现的时间最早,G波总的持续时间和每次刺探G波的平均持续时间都明显长于麦长管蚜和麦二叉蚜。麦长管蚜第1次E1波的时间、E1波总的持续时间和每次刺探E1波的平均持续时间都明显比麦二叉蚜和禾谷缢管蚜要长。麦二叉蚜E2波总的持续时间和每次刺探E2波的平均持续时间都明显长于麦长管蚜和禾谷缢管蚜。表明3种蚜虫各自拥有不同取食策略。禾谷缢管蚜比其它两种蚜虫需要更多的水分和无机盐,麦长管蚜通过分泌大量唾液增大对食物的利用率,麦二叉蚜通过增加韧皮部取食时间以满足对营养的需要。(2)刺探过程中麦二叉蚜pd波出现的次数为(51.97±7.82)次,高于麦长管蚜的(44.73±4.52)次和禾谷缢管蚜的(32.99±4.22)次。麦二叉蚜pd波Ⅱ-2和Ⅱ-3亚波的时间最长,禾谷缢管蚜最短,三者之间差异达显著水平。表明与其它两种麦蚜相比,麦二叉蚜在取食过程中口针与细胞间的接触频率更高,与细胞内获毒和传毒相关的Ⅱ-3波和Ⅱ-2波持续时间更长,增加了获毒和传毒的几率,是其传毒能力最强的机理。
Characterization and discrimination of three Rhopalosiphum species (Homoptera: Aphididae) based on isozymes
Lázzari, Sonia M. N.;
Revista Brasileira de Zoologia , 1992, DOI: 10.1590/S0101-81751992000100015
Abstract: seventeen clones of rhopalosiphum padi (linnaeus, 1758), 14 of r. maidis (fitch, 1856), and two of r. insertum (walker, 1849), representing a wide range of host plants and geographic distribution, were examined electrophoretically to determine intra and interspecific variation. twenty-one enzyme systems were tested using starch-gel techniques. the electromorph variation within species was low, as expected for parthenogenetic organisms. frequency of heterozygotes was also relatively low for most populations. the percentage of polymorphic loci ranged from 0% to 27.3% in r. padi, but it was lower (0% to 18.2%) in the completely an holocyclic r. maidis. no consistent correlation between band patterns and host plant or geographic origin could be established for r. padi and r. maidis. the distinction between r. padi and r. insertum was made by est-1, lap-2, pgm, got-1,and α-gpdh.the enzymes est-2, g-3pdh, sdh, and got-2 were useful to separate r. maidis from r. padi, while est-1, lap-2, got-1, and α-gpdh, in addition to the first three mentioned above, separated r. maidis from r. insertum. however, many other loci shared only one electromorph and had another that was useful to partially distinguish the species. the utilization of starch-gel electrophoresis as a taxonomic tool in distinguishing populations and species of aphids and its combination with other taxonomic methods are briefly discussed.
Rhopalosiphum padi Feeding – Attempted Symptomatic Defence Mechanisms in Barley Leaves Include Wound Callose Deposition?  [cached]
Sefiu Adekilekun SAHEED,Christiaan Edward Johannes BOTHA
Notulae Scientia Biologicae , 2010,
Abstract: The deposition of callose and the damage-related symptoms subsequently expressed by infested plants were investigated after feeding on barley leaves by bird cherry-oat aphid (BCA), Rhopalosiphum padi L. Feeding by this aphid does not result in appearance of visible damage to the plants, provided the feeding population is small. Using aniline blue fluorochrome, we confirmed that whilst low feeding density (5 aphids) results in appearance of wound callose in sieve tubes, this only occurs after 14d of feeding, when the feeding population had increased. Continued feeding results in progressively more callose deposition and by 21d, severe damage has been caused. In contrast, feeding by larger populations (50 adult aphids), results in the appearance of wound callose within 72h, in longitudinal and cross veins. We suggest that this wounding response appears to play a role in the appearance of golden yellow streak symptoms reported to occur in leaves where BCA feeding density was high.
E ciência e seletividade de inseticidas no controle de Schizaphis graminum e Rhopalosiphum padi (Hemiptera, Aphididae) em lavoura de aveia preta / Ef ciency and selectivity of insecticides in the control of Schizaphis graminum and Rhopalosiphum padi (Hemiptera, Aphididae) in black oat crops  [cached]
Flávio Roberto Mello Garcia
Ambiência , 2008,
Abstract: O objetivo do estudo foi avaliar a e ciência e a seletividade de diferentesinseticidas usados via tratamento de semente no controle dos pulg es na cultura da aveia bem produ o de matéria. O ensaio foi conduzido em Faxinal dos Guedes, SC, no ano agrícola de 2005 em condi es de campo,com cinco tratamentos e quatro repeti es. Para a avalia o da e ciência foi utilizada a contagem de insetos vivos e, para a seletividade, contou-seo número de pulg es mumi cados. Todos controlaram signi cativamenteos insetos, sendo os tratamentos imidacloprid e tiametoxam superiores a carbossulfam e acephato. O acephato e carbossulfam foram os mais seletivos, seguidos por imidacloprid e tiametoxam que n o diferiram entresi. Os tratamentos que tiveram maior e ciência no controle favoreceram o incremento de matéria seca.
Sequencing and Validation of Reference Genes to Analyze Endogenous Gene Expression and Quantify Yellow Dwarf Viruses Using RT-qPCR in Viruliferous Rhopalosiphum padi  [PDF]
Keke Wu, Wenwen Liu, Thithi Mar, Yan Liu, Yunfeng Wu, Xifeng Wang
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0097038
Abstract: The bird cherry-oat aphid (Rhopalosiphum padi), an important pest of cereal crops, not only directly sucks sap from plants, but also transmits a number of plant viruses, collectively the yellow dwarf viruses (YDVs). For quantifying changes in gene expression in vector aphids, reverse transcription-quantitative polymerase chain reaction (RT-qPCR) is a touchstone method, but the selection and validation of housekeeping genes (HKGs) as reference genes to normalize the expression level of endogenous genes of the vector and for exogenous genes of the virus in the aphids is critical to obtaining valid results. Such an assessment has not been done, however, for R. padi and YDVs. Here, we tested three algorithms (GeNorm, NormFinder and BestKeeper) to assess the suitability of candidate reference genes (EF-1α, ACT1, GAPDH, 18S rRNA) in 6 combinations of YDV and vector aphid morph. EF-1α and ACT1 together or in combination with GAPDH or with GAPDH and 18S rRNA could confidently be used to normalize virus titre and expression levels of endogenous genes in winged or wingless R. padi infected with Barley yellow dwarf virus isolates (BYDV)-PAV and BYDV-GAV. The use of only one reference gene, whether the most stably expressed (EF-1α) or the least stably expressed (18S rRNA), was not adequate for obtaining valid relative expression data from the RT-qPCR. Because of discrepancies among values for changes in relative expression obtained using 3 regions of the same gene, different regions of an endogenous aphid gene, including each terminus and the middle, should be analyzed at the same time with RT-qPCR. Our results highlight the necessity of choosing the best reference genes to obtain valid experimental data and provide several HKGs for relative quantification of virus titre in YDV-viruliferous aphids.
Cloning and Prokaryotic Expression of Viral Binding Protein(VBP) Gene From Endosybiotic Bacterium of Rhopalosiphum padi

Wu Yunfeng,Cui Xiaofeng,Lin Lin,Zhou Guanghe,

微生物学报 , 2002,
Abstract: Viral binding protein gene from Rhopalosiphum padi Yangling biotype was amplified by PCR method and then cloned.The complete nucleotide sequence of the gene was determined,It has 1647 nucleotides encoding 548 amino acids.Comparison showed this gene has 97% identity on nucleotide level with Buchnera groEL AM gene of Rhopalosiphum padi American biotype,while has 97.4% identity on amino acid level was found between this two genes.The VBP gene was ligated into pBV221 and pET30a expression vector and expressed the aim protein 63kD and 69kD.
Double Subgenomic Alphaviruses Expressing Multiple Fluorescent Proteins Using a Rhopalosiphum padi Virus Internal Ribosome Entry Site Element  [PDF]
Michael R. Wiley,Lisa O. Roberts,Zach N. Adelman,Kevin M. Myles
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0013924
Abstract: Double subgenomic Sindbis virus (dsSINV) vectors are widely used for the expression of proteins, peptides, and RNA sequences. These recombinant RNA viruses permit high level expression of a heterologous sequence in a wide range of animals, tissues, and cells. However, the alphavirus genome structure and replication strategy is not readily amenable to the expression of more than one heterologous sequence. The Rhopalosiphum padi virus (RhPV) genome contains two internal ribosome entry site (IRES) elements that mediate cap-independent translation of the virus nonstructural and structural proteins. Most IRES elements that have been characterized function only in mammalian cells but previous work has shown that the IRES element present in the 5′ untranslated region (UTR) of the RhPV genome functions efficiently in mammalian, insect, and plant systems. To determine if the 5′ RhPV IRES element could be used to express more than one heterologous sequence from a dsSINV vector, RhPV 5′ IRES sequences were placed between genes for two different fluorescent marker proteins in the dsSINV, TE/3′2J/mcs. While mammalian and insect cells infected with recombinant viruses containing the RhPV sequences expressed both fluorescent marker proteins, only single marker proteins were routinely observed in cells infected with dsSINV vectors in which the RhPV IRES had been replaced by a luciferase fragment, an antisense RhPV IRES, or no intergenic sequence. Thus, we report development of a versatile tool for the expression of multiple sequences in diverse cell types.
Plantas infestantes hospedeiras de Rhopalosiphum rufiabdominalis (Sasaki) (Hemiptera: Aphididae) em áreas de cultivo de arroz irrigado
Maziero, Heleno;Guedes, Jerson V.C.;Kruse, Nelson D.;Farias, Juliano R.;
Neotropical Entomology , 2007, DOI: 10.1590/S1519-566X2007000300017
Abstract: rhopalosiphum rufiabdominalis (sasaki) is an insect of world-wide distribution that damages irrigated rice. from september, 2004 to february, 2005, nymphs and adults of this aphid were collected in several host weeds of rice farms in alegrete, quaraí and uruguaiana, located in western of state of rio grande do sul, and restinga seca, in central region of this state, brazil. the insect was found in the root of andropogon bicornis (west indian foxtail), echinochloa colona (jungle rice), oryza sativa (volunteer rice and red-rice), paspalum sp. (paspalum) and soliva pterosperma (lawn burweed).
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