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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.
Population Growth of Rhopalosiphum padi L. (Homoptera: Aphididae) on Different Cereal Crops from the Semiarid Pampas of Argentina under Laboratory Conditions Crecimiento Poblacional de Rhopalosiphum padi L. (Homoptera: Aphididae) sobre Diferentes Cereales de la Pampas Semiárida de Argentina en Condiciones de Laboratorio  [cached]
Lilian R Descamps,Carolina Sánchez Chopa
Chilean Journal of Agricultural Research , 2011,
Abstract: The bird cherry-oat aphid Rhopalosiphum padi L. (Homoptera: Aphididae) is one of the main pests in a number of crops in the semiarid Pampas of Argentina. In the present study, the effect of different host plants, including Triticum aestivum L., ×Triticosecale Wittm., Hordeum vulgare L., Hordeum distichum L., Avena sativa L., and Secale cereale L. on biological parameters of R. padi L. was studied in the laboratory at 24 ± 1 °C, 65 ± 10% RH and a 14:10 photoperiod. Longevity, intrinsic rate of natural increase (r m), net reproductive rate (R0), mean generation time (T), doubling time (DT), and finite rate of increase (λ) of the bird cherry-oat aphid on the different cereal crops were estimated. Differences in fertility life table parameters of R. padi among host plants were analyzed using pseudo-values, which were produced by Jackknife re-sampling. Results indicated that beer barley might be the most suitable food for R. padi due to greater adult longevity (20.88 d), higher fecundity (41 nymphs female-1), higher intrinsic rate of natural increase (0.309 females female-1 d-1), lower doubling time (2.24), and lower nymphal mortality (22.2%). Therefore, it can be concluded from the present study that R. padi prefers beer barley for fast and healthy development over other cereal crops. El áfido Rhopalosiphum padi L. (Homoptera: Aphididae) es una de las principales plagas de numerosos cultivos de la región semiárida pampeana de Argentina. En el presente trabajo se estudió el efecto de diferentes cereales incluidos Triticum aestivum L., ×Triticosecale Wittm., Hordeum vulgare L., Hordeum distichum L., Avena sativa L. and Secale cereale L. sobre los parámetros biológicos de R. padi en laboratorio. Se estimaron longevidad, tasa intrínseca de crecimiento natural (r m), tasa neta de reproducción (R0), tiempo generacional medio (T), tiempo de duplicación (TD), y tasa finita de incremento (λ) del pulgón de la avena en diferentes cereales. Las diferencias de los parámetros biológicos de R. padi entre los distintos cultivos fueron analizadas utilizando pseudovalores con la técnica de Jackknife. Los resultados indican que la cebada cervecera podría ser el cultivo más preferido por este áfido debido a la larga longevidad (20,88 d), la alta fecundidad (41 ninfas hembra-1), la alta tasa de incremento natural (0,309 hembras hembra-1 d-1), el corto tiempo de duplicación (2,24 d) y la baja mortalidad ninfal (22,2%). De los resultados obtenidos podemos inferir que R. padi tiene una mejor performance sobre la cebada cervecera que sobre el resto de cereales utilizados en este tr
Population Growth of Rhopalosiphum padi L. (Homoptera: Aphididae) on Different Cereal Crops from the Semiarid Pampas of Argentina under Laboratory Conditions
Descamps,Lilian R; Sánchez Chopa,Carolina;
Chilean journal of agricultural research , 2011, DOI: 10.4067/S0718-58392011000300007
Abstract: the bird cherry-oat aphid rhopalosiphum padi l. (homoptera: aphididae) is one of the main pests in a number of crops in the semiarid pampas of argentina. in the present study, the effect of different host plants, including triticum aestivum l., ×triticosecale wittm., hordeum vulgare l., hordeum distichum l., avena sativa l., and secale cereale l. on biological parameters of r. padi l. was studied in the laboratory at 24 ± 1 °c, 65 ± 10% rh and a 14:10 photoperiod. longevity, intrinsic rate of natural increase (rm), net reproductive rate (r0), mean generation time (t), doubling time (dt), and finite rate of increase (λ) of the bird cherry-oat aphid on the different cereal crops were estimated. differences in fertility life table parameters of r. padi among host plants were analyzed using pseudo-values, which were produced by jackknife re-sampling. results indicated that beer barley might be the most suitable food for r. padi due to greater adult longevity (20.88 d), higher fecundity (41 nymphs female-1), higher intrinsic rate of natural increase (0.309 females female-1 d-1), lower doubling time (2.24), and lower nymphal mortality (22.2%). therefore, it can be concluded from the present study that r. padi prefers beer barley for fast and healthy development over other cereal crops.
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.
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
禾谷缢管蚜体内的病毒结合蛋白基因的克隆与原核表达

Wu Yunfeng,Cui Xiaofeng,Lin Lin,Zhou Guanghe,
吴云锋
,崔晓锋,林林,周广和

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.
Diversidade de afídeos na cultura do algodoeiro no município de Campo Verde (MT)  [cached]
Michelotto Marcos Doniseti,Busoli Antonio Carlos
Bragantia , 2003,
Abstract: O objetivo deste trabalho foi verificar a diversidade de afídeos (Hemiptera: Aphididae) na cultura do algodoeiro (Gossypium hirsutum L.) no município de Campo Verde (MT). Os afídeos foram amostrados diretamente nas plantas e através de armadilhas tipo Moericke. As amostragens foram realizadas a cada dois dias, até 60 dias após a germina o das plantas. A espécie Aphis gossypii Glover prevaleceu nas amostragens realizadas sobre as plantas. Formas aladas, de ocorrência acidental na cultura, tais como Aphis spiraecola Patch e Rhopalosiphum padi (Linnaeus) também foram observadas. Com as armadilhas tipo Moericke foram capturados 2280 afídeos alados, pertencentes a 13 espécies: R. padi (52,6% do total), A. spiraecola (26,4%), A. gossypii (8,9%), Rhopalosiphum maidis (Fitch) (5,3%), Geopemphigus floccosus (Moreira) (3,1%), Uroleucon ambrosiae (Thomas) (1,5%), Rhopalosiphum rufiabdominalis (Sasaki) (1,3%), Myzus persicae (Sulzer) (0,4%), Sipha flava (Forbes) (0,3%), Pentalonia nigronervosa Coquerel, Tetraneura nigriabdominalis (Sasaki), Lizerius melanocallis (Quednau) e Toxoptera citricidus (Kirkaldy) (0,1% cada uma). Nas amostragens diretamente sobre as plantas foram observados ápteros e alados de A. gossypii e alados de A. spiraecola e R. padi. Nas armadilhas tipo Moericke, as principais espécies capturadas foram R. padi, A. spiraecola, A. gossypii e R. maidis.
Occurrence and parasitism of aphids (Hemiptera: Aphididae) on cultivars of irrigated oat (Avena spp.) in S?o Carlos, Brazil
Ronquim, Júlio Cesar;Pacheco, Josué Marques;Ronquim, Carlos Cesar;
Brazilian Archives of Biology and Technology , 2004, DOI: 10.1590/S1516-89132004000200001
Abstract: the interactions between aphids and their hymenopteran parasitoids on irrigated oats as well as the response of different cultivars of cereals regarding the resistance to these aphids and the influence on the host/parasitoid relationships were studied during two years in s?o carlos, brazil. rhopalosiphum padi (l.) was the predominant aphid observed throughout the study, while the other species were rarely found. five species of parasitic hymenoptera were found: three primary parasitoids, lysiphlebus testaceipes (cresson), aphidius colemani (viereck) and diaeretiella rapae (m'intosh) and two hyperparasitoids, syrphophagus aphidivorus (myer) and alloxysta brassicae (ashmead). the upf 86081 cultivar presented significant results regarding lower rhopalosiphum padi contamination and higher aphid parasitism rates than those observed on some other cultivars. no significant effect on the percentage variation of parasitoid emergence on the mummified aphids was observed throughout this study.
Occurrence and parasitism of aphids (Hemiptera: Aphididae) on cultivars of irrigated oat (Avena spp.) in S o Carlos, Brazil  [cached]
Ronquim Júlio Cesar,Pacheco Josué Marques,Ronquim Carlos Cesar
Brazilian Archives of Biology and Technology , 2004,
Abstract: The interactions between aphids and their Hymenopteran parasitoids on irrigated oats as well as the response of different cultivars of cereals regarding the resistance to these aphids and the influence on the host/parasitoid relationships were studied during two years in S o Carlos, Brazil. Rhopalosiphum padi (L.) was the predominant aphid observed throughout the study, while the other species were rarely found. Five species of parasitic Hymenoptera were found: three primary parasitoids, Lysiphlebus testaceipes (Cresson), Aphidius colemani (Viereck) and Diaeretiella rapae (M'Intosh) and two hyperparasitoids, Syrphophagus aphidivorus (Myer) and Alloxysta brassicae (Ashmead). The UPF 86081 cultivar presented significant results regarding lower Rhopalosiphum padi contamination and higher aphid parasitism rates than those observed on some other cultivars. No significant effect on the percentage variation of parasitoid emergence on the mummified aphids was observed throughout this study.
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