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Frank B. Peairs - One of the best experts on this subject based on the ideXlab platform.
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Damage and Yield Response of Wheat Lines with Dn4 and Dn7 Genes Resistant to Russian Wheat Aphid Biotype RWA21
Southwestern Entomologist, 2020Co-Authors: Darren M. Cockrell, Terri L. Randolph, Cynthia B. Walker, Rachael A. Sitz, Scott D. Haley, Frank B. PeairsAbstract:Plant damage and yield responses to three infestation levels (0, 1, and 10x) of biotype RWA2 Russian Wheat Aphid, Diuraphis noxia (Kurdjumov), were compared in winter Wheat, Triticum aestivum L., during the 2010-11, 2011-12, and 2012-13 growing seasons at two sites in eastern Colorado. Wheat lines contained either no resistance gene (Yuma), Dn4 resistance (Yumar), or the Dn7 resistance gene (CO08RWA050). Fewer Russian Wheat Aphids and symptomatic tillers were on CO08RWA050 at any infestation. Yuma and Yumar tillers had an average of seven times more Aphids present than CO08RWA050. Yields decreased as infestation increased in Yuma and Yumar, but yield was not less in CO08RWA050 at any infestation level. Kernel weights of Yuma and Yumar, but not CO08RWA050, were less with greater infestation. Data from the study suggested that resistance conferred by the Dn7 gene would be effective in reducing Russian Wheat Aphid abundance, and ultimately benefit Wheat producers during outbreak years.
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change in biotypic diversity of Russian Wheat Aphid hemiptera Aphididae populations in the united states
Journal of Economic Entomology, 2015Co-Authors: Gary J Puterka, Terri L. Randolph, Frank B. Peairs, Scott J Nicholson, M J Brown, Kristopher L Giles, Robert W Hammon, G J Michaels, E D Bynum, T L SpringerAbstract:A key component of Russian Wheat Aphid, Diuraphis noxia (Kurdjumov), management has been through planting resistant Wheat cultivars. A new biotype, RWA2, appeared in 2003 which caused widespread damage to Wheat cultivars containing the Dn4 gene. Biotypic diversity in Russian Wheat Aphid populations has not been addressed since 2005 when RWA2 dominated the biotype complex. Our objectives were to determine the biotypic diversity in the Central Great Plains and Colorado Plateau at regional (2010, 2011, 2013) and local (2012) levels and detect the presence of new Russian Wheat Aphid biotypes. Regional and within-field Aphid collections were screened against Russian Wheat Aphid-resistant Wheat genotypes containing genes Dn3, Dn4, Dn6, Dn7, Dn9, CI2401; and resistant barley STARS 9301B. In 2010, all Aphid collections from Texas were avirulent to the Dn4 resistance gene in Wheat. Regional results revealed Dn4 avirulent RWA6 was widespread (55-84%) in populations infesting Wheat in both regions. Biotypes RWA1, 2, and 3/7 were equally represented with percentages<20% each while RWA8 was rarely detected. Combining percentages of RWA1, 6, and 8 across regions to estimate avirulence to Dn4 gene revealed high percentages for both 2011 (64-80%) and 2013 (69-90%). In contrast, the biotype structure at the local level differed where biotype percentages varied up to ≥2-fold between fields. No new biotypes were detected; therefore, Dn7, CI2401, and STARS9301B remained resistant to all known Russian Wheat Aphid biotypes. This study documents a shift to Dn4 avirulent biotypes and serves as a valuable baseline for biotypic diversity in Russian Wheat Aphid populations prior to the deployment of new Russian Wheat Aphid-resistant Wheat cultivars.
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effects of planting date and barley variety on Russian Wheat Aphid hemiptera Aphididae populations in colorado kansas and nebraska
Journal of Economic Entomology, 2014Co-Authors: Paola Sotelo, Frank B. Peairs, Gary L Hein, C M SmithAbstract:ABSTRACT The Russian Wheat Aphid, Diuraphis noxia (Kurdjumov) (Hemiptera: Aphididae), is an important pest in the western Great Plains of the United States, where it causes hundreds of millions of dollars of losses to barley and Wheat production through reduced yields. Experiments to evaluate the effect of early planting and resistance in barley (Hordeum vulgare L.) on D. noxia were conducted at Fort Collins, CO; Tribune, KS; and Sidney, NE, in 2007, 2008, and 2009. Treatments included two planting dates and four cultivars, the D. noxia-resistant barley cultivars ‘Stoneham’ (Otis*4/STARS 9577B) and ‘Sidney’ (Otis*4/STARS 9301B), the susceptible cultivar ‘Otis’, and Otis treated with thiamethoxam. In tiller samples collected from May through early July, consistently lower D. noxia populations were found in plots planted ≈30 d earlier than normal at Fort Collins in all three years, and at Tribune in 2007. With one location-year exception, lower D. noxia populations occurred on plants of resistant varieties ...
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characterization of eight Russian Wheat Aphid hemiptera Aphididae biotypes using two category resistant susceptible plant responses
Journal of Economic Entomology, 2014Co-Authors: Gary J Puterka, Frank B. Peairs, Scott J Nicholson, M J Brown, W R Cooper, Terri L. RandolphAbstract:ABSTRACT Eight biotypes of the Russian Wheat Aphid, Diuraphis noxia (Kurdjumov), have been discovered in the United States since 2003. Biotypes are identified by the distinct feeding damage responses they produce on Wheat carrying different Russian Wheat Aphid resistance genes, namely, from Dn1 to Dn9. Each Russian Wheat Aphid biotype has been named using plant damage criteria and virulence categories that have varied between studies. The study was initiated to compare the plant damage caused by all the eight known Russian Wheat Aphid biotypes, and analyze the results to determine how Russian Wheat Aphid virulence should be classified. Each Russian Wheat Aphid biotype was evaluated on 16 resistant or susceptible cereal genotypes. Plant damage criteria included leaf roll, leaf chlorosis, and plant height. The distribution of chlorosis ratings followed a bimodal pattern indicating two categories of plant responses, resistant or susceptible. Correlations were significant between chlorosis ratings and leaf ro...
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quantifying Russian Wheat Aphid pest intensity across the great plains
Environmental Entomology, 2012Co-Authors: Scott C Merrill, Frank B. PeairsAbstract:ABSTRACT Wheat, the most important cereal crop in the Northern Hemisphere, is at-risk for an approximate 10% reduction in worldwide production because of animal pests. The potential economic impact of cereal crop pests has resulted in substantial research efforts into the understanding of pest agroecosystems and development of pest management strategy. Management strategy is informed frequently by models that describe the population dynamics of important crop pests and because of the economic impact of these pests, many models have been developed. Yet, limited effort has ensued to compare and contrast models for their strategic applicability and quality. One of the most damaging pests of Wheat in North America is the Russian Wheat Aphid, Diuraphis noxia (Kurdjumov). Eighteen D. noxia population dynamic models were developed from the literature to describe pest intensity. The strongest models quantified the negative effects of fall and spring precipitation on Aphid intensity, and the positive effects assoc...
Annamaria Botha - One of the best experts on this subject based on the ideXlab platform.
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bacteria associated with Russian Wheat Aphid diuraphis noxia enhance Aphid virulence to Wheat
Phytobiomes journal, 2018Co-Authors: Emily K Luna, Tony Campillo, Annamaria Botha, Leon Van Eck, Margaret D Weinroth, Jessica L Metcalf, Alvaro L Perezquintero, Theodore W Thannhauser, Darryl J Pappin, Ned TisseratAbstract:Phenotypic responses to biotic stresses are often studied as the interactions between two species; however, in the phytobiome, these responses frequently result from complex interactions involving several organisms. Here, we show that variation in chlorosis caused by Russian Wheat Aphid (Diuraphis noxia) feeding is determined, in part, by Aphid-associated bacteria. Proteomic analysis of fluids injected into a sterile medium by the Aphid during feeding indicate that 99% of the proteins are of bacterial origin. Of these, the greatest proportion are produced by bacteria in the order Enterobacteriales. Bacteria from five genera in four families that have the capacity to produce these proteins were isolated directly from Aphids as well as from Wheat leaves only after D. noxia feeding. By themselves or in combination, these bacteria were not virulent to Wheat, even at high inoculum levels. Metagenomic analysis showed that the same five D. noxia-associated genera dominated the non-Buchnera component of the Aphid microbiome, and that representation of these genera was reduced in Aphids from colonies established after isolation of newborn nymphs from their mothers prior to feeding (isolated Aphids). Isolation or treatment with antibiotics reduced bacterial numbers, and these Aphids caused less feeding damage on Wheat than non-isolated or non-antibiotic-treated Aphids. Our data show that bacterial proteins are a significant component of Russian Wheat Aphid saliva, that the bacteria producing these proteins are associated with Aphids and plants fed upon by Aphids, and that these Aphid-associated bacteria facilitate Aphid virulence to Wheat.
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genome of Russian Wheat Aphid an economically important cereal Aphid
Standards in Genomic Sciences, 2017Co-Authors: Nicolaas Francois Visser Burger, Annamaria BothaAbstract:Although the hemipterans ( Aphididae ) are comprised of roughly 50,000 extant insect species, only four have sequenced genomes that are publically available, namely (pea Aphid), (Kissing bug), (Green peach Aphid) and (Russian Wheat Aphid). As a significant proportion of agricultural pests are phloem feeding Aphids, it is crucial for sustained global food security that a greater understanding of the genomic and molecular functioning of this family be elucidated. Recently, the genome of US D. noxia biotype US2 was sequenced but its assembly only incorporated ~ 32% of produced reads and contained a surprisingly low gene count when compared to that of the model/first sequenced Aphid, . To this end, we present here the genomes of two South African (Kurdjumov, Hemiptera : Aphididae ) biotypes (SA1 and SAM), obtained after sequencing the genomes of the only two D. noxia biotypes with documented linked genealogy. To better understand overall targets and patterns of heterozygosity, we also sequenced a pooled sample of 9 geographically separated D. noxia populations (MixIX). We assembled a 399 Mb reference genome ( PRJNA297165 , representing 64% of the projected genome size 623 Mb) using ± 28 Gb of 101 bp paired-end HiSeq2000 reads from the D. noxia biotype SAM, whilst ± 13 Gb 101 bp paired-end HiSeq2000 reads from the D. noxia biotype SA1 were generated to facilitate genomic comparisons between the two biotypes. Sequencing the MixIX sample yielded ±26 Gb 50 bp paired-end SOLiD reads which facilitated SNP detection when compared to the D. noxia biotype SAM assembly. Ab initio gene calling produced a total of 31,885 protein coding genes from the assembled contigs spanning ~ 399 Mb (GCA_001465515.1).
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Genome of Russian Wheat Aphid an economically important cereal Aphid
BMC, 2017Co-Authors: Nicolaas Francois Visser Burger, Annamaria BothaAbstract:Abstract Although the hemipterans ( Aphididae ) are comprised of roughly 50,000 extant insect species, only four have sequenced genomes that are publically available, namely Acyrthosiphon pisum (pea Aphid), Rhodnius prolixus (Kissing bug), Myzus persicae (Green peach Aphid) and Diuraphis noxia (Russian Wheat Aphid). As a significant proportion of agricultural pests are phloem feeding Aphids, it is crucial for sustained global food security that a greater understanding of the genomic and molecular functioning of this family be elucidated. Recently, the genome of US D. noxia biotype US2 was sequenced but its assembly only incorporated ~ 32% of produced reads and contained a surprisingly low gene count when compared to that of the model/first sequenced Aphid, A. pisum . To this end, we present here the genomes of two South African Diuraphis noxia (Kurdjumov, Hemiptera : Aphididae ) biotypes (SA1 and SAM), obtained after sequencing the genomes of the only two D. noxia biotypes with documented linked genealogy. To better understand overall targets and patterns of heterozygosity, we also sequenced a pooled sample of 9 geographically separated D. noxia populations (MixIX). We assembled a 399 Mb reference genome ( PRJNA297165 , representing 64% of the projected genome size 623 Mb) using ± 28 Gb of 101 bp paired-end HiSeq2000 reads from the D. noxia biotype SAM, whilst ± 13 Gb 101 bp paired-end HiSeq2000 reads from the D. noxia biotype SA1 were generated to facilitate genomic comparisons between the two biotypes. Sequencing the MixIX sample yielded ±26 Gb 50 bp paired-end SOLiD reads which facilitated SNP detection when compared to the D. noxia biotype SAM assembly. Ab initio gene calling produced a total of 31,885 protein coding genes from the assembled contigs spanning ~ 399 Mb (GCA_001465515.1)
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fractionated extracts of Russian Wheat Aphid eliciting defense responses in Wheat
Journal of Economic Entomology, 2007Co-Authors: Nora L V Lapitan, Junhua Peng, Annamaria BothaAbstract:Abstract It is hypothesized that the interaction between Aphids and plants follows a gene-for-gene model. The recent appearance of several new Russian Wheat Aphid,Diuraphis noxia (Kurdjumov) (Homoptera: Aphididae), biotypes in the United States and the differential response of Wheat,Triticum aestivum L., genotypes containing different resistance genes also suggest a gene-for-gene interaction. However, Aphid elicitors remain unknown. This study was conducted to identify fractionated Russian Wheat Aphid extracts capable of eliciting differential responses between resistant and susceptible Wheat genotypes. We extracted whole soluble compounds and separated proteins and metabolites from two Russian Wheat Aphid biotypes (1 and 2), injected these extracts into seedlings of susceptible Wheat Gamtoos (dn7) and resistant 94M370 (Dn7), and determined phenotypic and biochemical plant responses. Injections of whole extract or protein extract from both biotypes induced the typical susceptible symptom, leaf rolling, in...
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cereal host interactions with Russian Wheat Aphid a review
Journal of Plant Interactions, 2005Co-Authors: Annamaria Botha, Nora L V LapitanAbstract:Abstract A lack of understanding the interaction between the Russian Wheat Aphid (RWA) and its host plant is a limitation in developing effective strategies for controlling the Aphid. It is generally assumed that the interaction between Aphid and plant is similar to that between plant and pathogen; that is, an elicitor from the insect is recognized by a protein from the host plant and a cascade of signal transduction events follows. However, evidence suggests that RWA feeding is eliciting both the SA- and JA/ethylene-dependent signaling pathways by mimicking aspects of both pathogen and herbivorous insect attacks. Results further suggest that phenotypic symptoms after RWA feeding are under regulation via two independent reactions, namely an immediate response (i.e., leaf rolling) and a downstream event (i.e., chlorosis). These defense responses enable a resistant host plant to defend itself and overcome the stress response, while their susceptible counterparts die. The processes involved in the onset of t...
Nora L V Lapitan - One of the best experts on this subject based on the ideXlab platform.
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Accessing a Russian Wheat Aphid Resistance Gene in Bread Wheat by Long-Read Technologies.
eScholarship University of California, 2019Co-Authors: Tulpová Zuzana, Nora L V Lapitan, Toegelová Helena, Peairs, Frank B, Macas Jiří, Novák Petr, Lukaszewski, Adam J, Kopecký David, Mazáčová Mira, Vrána JanAbstract:Russian Wheat Aphid (RWA) ( Kurdjumov) is a serious invasive pest of small-grain cereals and many grass species. An efficient strategy to defy Aphid attacks is to identify sources of natural resistance and transfer resistance genes into susceptible crop cultivars. Revealing the genes helps understand plant defense mechanisms and engineer plants with durable resistance to the pest. To date, more than 15 RWA resistance genes have been identified in Wheat ( L.) but none of them has been cloned. Previously, we genetically mapped the RWA resistance gene into an interval of 0.83 cM on the short arm of chromosome 7D and spanned it with five bacterial artificial chromosome (BAC) clones. Here, we used a targeted strategy combining traditional approaches toward gene cloning (genetic mapping and sequencing of BAC clones) with novel technologies, including optical mapping and long-read nanopore sequencing. The latter, with reads spanning the entire length of a BAC insert, enabled us to assemble the whole region, a task that was not achievable with short reads. Long-read optical mapping validated the DNA sequence in the interval and revealed a difference in the locus organization between resistant and susceptible genotypes. The complete and accurate sequence of the region facilitated the identification of new markers and precise annotation of the interval, revealing six high-confidence genes. Identification of as the most likely candidate opens an avenue for its validation through functional genomics approaches
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chromosomal genomics facilitates fine mapping of a Russian Wheat Aphid resistance gene
Theoretical and Applied Genetics, 2015Co-Authors: Helena Staňkova, Nora L V Lapitan, Miroslav Valarik, Paul J Berkman, Jacqueline Batley, David Edwards, Mingcheng Luo, Zuzana Tulpova, Marie Kubalakova, Nils SteinAbstract:Making use of Wheat chromosomal resources, we developed 11 gene-associated markers for the region of interest, which allowed reducing gene interval and spanning it by four BAC clones. Positional gene cloning and targeted marker development in bread Wheat are hampered by high complexity and polyploidy of its nuclear genome. Aiming to clone a Russian Wheat Aphid resistance gene Dn2401 located on Wheat chromosome arm 7DS, we have developed a strategy overcoming problems due to polyploidy and enabling efficient development of gene-associated markers from the region of interest. We employed information gathered by GenomeZipper, a synteny-based tool combining sequence data of rice, Brachypodium, sorghum and barley, and took advantage of a high-density linkage map of Aegilops tauschii. To ensure genome- and locus-specificity of markers, we made use of survey sequence assemblies of isolated Wheat chromosomes 7A, 7B and 7D. Despite the low level of polymorphism of the Wheat D subgenome, our approach allowed us to add in an efficient and cost-effective manner 11 new gene-associated markers in the Dn2401 region and narrow down the target interval to 0.83 cM. Screening 7DS-specific BAC library with the flanking markers revealed a contig of four BAC clones that span the Dn2401 region in Wheat cultivar ‘Chinese Spring’. With the availability of sequence assemblies and GenomeZippers for each of the Wheat chromosome arms, the proposed strategy can be applied for focused marker development in any region of the Wheat genome.
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inheritance of Russian Wheat Aphid resistance from tetraploid Wheat accessions during transfer to hexaploid Wheat
Euphytica, 2011Co-Authors: Benjamin M Beyer, Scott D. Haley, Nora L V Lapitan, Junhua Peng, Frank B. PeairsAbstract:Identification of new sources of resistance to Russian Wheat Aphid (RWA) (Diuraphis noxia (Kurdjumov) in Wheat (Triticum aestivum L.) has become very important with the identification of several new biotypes since 2003. Our objective was to characterize inheritance and expression of resistance to RWA biotype 2 from three tetraploid Wheat landraces (Triticum turgidum L. subsp. dicoccon) during transfer to hexaploid Wheat. Resistant tetraploid accessions PI 624903, PI 624904, and PI 624908 were crossed to the susceptible hexaploid cultivars ‘Len’ and ‘Coteau’. Resistant F1 progeny were advanced to the F2:3 by self-pollination and to the BC1F2 and BC2F1 by backcrossing. Leaf rolling and chlorosis were recorded in standard seedling screening tests on F1 and F2:3 individuals while the F2, BC1F1, BC1F2, and BC2F1 were scored as resistant or susceptible. Segregation in the BC1F1 and BC2F1 fit a 1:1 resistant:susceptible ratio, indicative of control by a single dominant gene. Segregation for resistance in the F2 did not fit 3:1, 13:3, or 15:1 ratios for any of the resistant accessions. Expression of resistance in homogeneous resistant F2:3 lines was greater than susceptible checks, similar to the resistant tetraploid accessions, and less than a line carrying the Dn7 resistance gene. Resistance derived from these tetraploid accessions will be useful to broaden the base of RWA resistance available for use in Wheat breeding.
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molecular mapping of the Russian Wheat Aphid resistance gene dn2414 in Wheat
Crop Science, 2007Co-Authors: Scott D. Haley, Frank B. Peairs, Junhua Peng, Hong Wang, Nora L V LapitanAbstract:Russian Wheat Aphid (RWA) [Diuraphis noxia (Kurdjumov)] is an important pest of Wheat (Triticum aestivum L.) in several production areas of the world. The most effective and economical approach for controlling RWA is to use resistant cultivars. A Wheat line, ST-ARS 02RWA2414-11 (2414-11), showed a high level of resistance to RWA biotype 2. Our objectives were to map the resistance gene and develop polymerase chain reaction (PCR)-based markers for marker-assisted selection (MAS). A mapping population of 212 F 2 individuals was developed from a cross of 2414-11 and the susceptible cultivar Yuma. The F 2 individuals and F 2:3 families were infested using biotype 2 RWA. The RWA resistance of 2414-11 is controlled by a single major gene, provisionally designated as Dn2414. Using standard PCR, 30 marker loci were found to be linked to Dn2414 with recombination frequencies (θ) of 0.00 to 0.27 and logarithm of the odds to the base 10 (LOD) scores of 7.6 to 66.1. Of the 30 markers, 26 were tightly linked to Dn2414 with θ ≤ 0.05. A genetic map was constructed consisting of 31 loci spanning a region of 34.7 cM. The close link-age of Dn2414 with several rye chromosome 1R short arm (1RS)-specific simple sequence repeat markers and low θ values around the Dn2414 gene indicate that Dn2414 is located on chromosome 1RS.1BL (translocation chromosome with IRS and Wheat chromosome 1B long arm). Phenotypic and marker profiles of 2414-11 and its relatives are the same as other lines known to carry Dn7. The Dn2414 gene is thus located on 1RS arm, and the large number of PCR markers will be valuable for MAS of this gene.
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fractionated extracts of Russian Wheat Aphid eliciting defense responses in Wheat
Journal of Economic Entomology, 2007Co-Authors: Nora L V Lapitan, Junhua Peng, Annamaria BothaAbstract:Abstract It is hypothesized that the interaction between Aphids and plants follows a gene-for-gene model. The recent appearance of several new Russian Wheat Aphid,Diuraphis noxia (Kurdjumov) (Homoptera: Aphididae), biotypes in the United States and the differential response of Wheat,Triticum aestivum L., genotypes containing different resistance genes also suggest a gene-for-gene interaction. However, Aphid elicitors remain unknown. This study was conducted to identify fractionated Russian Wheat Aphid extracts capable of eliciting differential responses between resistant and susceptible Wheat genotypes. We extracted whole soluble compounds and separated proteins and metabolites from two Russian Wheat Aphid biotypes (1 and 2), injected these extracts into seedlings of susceptible Wheat Gamtoos (dn7) and resistant 94M370 (Dn7), and determined phenotypic and biochemical plant responses. Injections of whole extract or protein extract from both biotypes induced the typical susceptible symptom, leaf rolling, in...
Terri L. Randolph - One of the best experts on this subject based on the ideXlab platform.
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Damage and Yield Response of Wheat Lines with Dn4 and Dn7 Genes Resistant to Russian Wheat Aphid Biotype RWA21
Southwestern Entomologist, 2020Co-Authors: Darren M. Cockrell, Terri L. Randolph, Cynthia B. Walker, Rachael A. Sitz, Scott D. Haley, Frank B. PeairsAbstract:Plant damage and yield responses to three infestation levels (0, 1, and 10x) of biotype RWA2 Russian Wheat Aphid, Diuraphis noxia (Kurdjumov), were compared in winter Wheat, Triticum aestivum L., during the 2010-11, 2011-12, and 2012-13 growing seasons at two sites in eastern Colorado. Wheat lines contained either no resistance gene (Yuma), Dn4 resistance (Yumar), or the Dn7 resistance gene (CO08RWA050). Fewer Russian Wheat Aphids and symptomatic tillers were on CO08RWA050 at any infestation. Yuma and Yumar tillers had an average of seven times more Aphids present than CO08RWA050. Yields decreased as infestation increased in Yuma and Yumar, but yield was not less in CO08RWA050 at any infestation level. Kernel weights of Yuma and Yumar, but not CO08RWA050, were less with greater infestation. Data from the study suggested that resistance conferred by the Dn7 gene would be effective in reducing Russian Wheat Aphid abundance, and ultimately benefit Wheat producers during outbreak years.
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change in biotypic diversity of Russian Wheat Aphid hemiptera Aphididae populations in the united states
Journal of Economic Entomology, 2015Co-Authors: Gary J Puterka, Terri L. Randolph, Frank B. Peairs, Scott J Nicholson, M J Brown, Kristopher L Giles, Robert W Hammon, G J Michaels, E D Bynum, T L SpringerAbstract:A key component of Russian Wheat Aphid, Diuraphis noxia (Kurdjumov), management has been through planting resistant Wheat cultivars. A new biotype, RWA2, appeared in 2003 which caused widespread damage to Wheat cultivars containing the Dn4 gene. Biotypic diversity in Russian Wheat Aphid populations has not been addressed since 2005 when RWA2 dominated the biotype complex. Our objectives were to determine the biotypic diversity in the Central Great Plains and Colorado Plateau at regional (2010, 2011, 2013) and local (2012) levels and detect the presence of new Russian Wheat Aphid biotypes. Regional and within-field Aphid collections were screened against Russian Wheat Aphid-resistant Wheat genotypes containing genes Dn3, Dn4, Dn6, Dn7, Dn9, CI2401; and resistant barley STARS 9301B. In 2010, all Aphid collections from Texas were avirulent to the Dn4 resistance gene in Wheat. Regional results revealed Dn4 avirulent RWA6 was widespread (55-84%) in populations infesting Wheat in both regions. Biotypes RWA1, 2, and 3/7 were equally represented with percentages<20% each while RWA8 was rarely detected. Combining percentages of RWA1, 6, and 8 across regions to estimate avirulence to Dn4 gene revealed high percentages for both 2011 (64-80%) and 2013 (69-90%). In contrast, the biotype structure at the local level differed where biotype percentages varied up to ≥2-fold between fields. No new biotypes were detected; therefore, Dn7, CI2401, and STARS9301B remained resistant to all known Russian Wheat Aphid biotypes. This study documents a shift to Dn4 avirulent biotypes and serves as a valuable baseline for biotypic diversity in Russian Wheat Aphid populations prior to the deployment of new Russian Wheat Aphid-resistant Wheat cultivars.
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characterization of eight Russian Wheat Aphid hemiptera Aphididae biotypes using two category resistant susceptible plant responses
Journal of Economic Entomology, 2014Co-Authors: Gary J Puterka, Frank B. Peairs, Scott J Nicholson, M J Brown, W R Cooper, Terri L. RandolphAbstract:ABSTRACT Eight biotypes of the Russian Wheat Aphid, Diuraphis noxia (Kurdjumov), have been discovered in the United States since 2003. Biotypes are identified by the distinct feeding damage responses they produce on Wheat carrying different Russian Wheat Aphid resistance genes, namely, from Dn1 to Dn9. Each Russian Wheat Aphid biotype has been named using plant damage criteria and virulence categories that have varied between studies. The study was initiated to compare the plant damage caused by all the eight known Russian Wheat Aphid biotypes, and analyze the results to determine how Russian Wheat Aphid virulence should be classified. Each Russian Wheat Aphid biotype was evaluated on 16 resistant or susceptible cereal genotypes. Plant damage criteria included leaf roll, leaf chlorosis, and plant height. The distribution of chlorosis ratings followed a bimodal pattern indicating two categories of plant responses, resistant or susceptible. Correlations were significant between chlorosis ratings and leaf ro...
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cyclical parthenogenetic reproduction in the Russian Wheat Aphid hemiptera Aphididae in the united states sexual reproduction and its outcome on biotypic diversity
Journal of Economic Entomology, 2012Co-Authors: Gary J Puterka, John D Burd, Terri L. Randolph, Frank B. Peairs, Robert W Hammon, W R CooperAbstract:In 1986, the Russian Wheat Aphid, Diuraphis noxia (Kurdjumov) (Hemiptera: Aphididae), became an invasive species of United States. Nearly 20 yr later, new biotypes appeared that were capable of overcoming most sources of resistance and became a renewed threat to Wheat, Triticum aestivum L., production. Cyclical (CP) and obligate (OP) parthenogenesis enables Aphids to both adapt to changing environments and exploit host resources. We documented these forms of reproduction for Russian Wheat Aphid in Wheat and wild grasses in the Central Great Plains and Rocky Mountain regions during falls 2004–2009. Colonies from sample sites also were held under unheated greenhouse conditions and observed for the presence of sexual morphs and eggs through the winter. Russian Wheat Aphid populations were mainly OP and attempted to overwinter as adults, regardless of region sampled. A few populations contained oviparae but no males (gynocyclic) and were not specific to any particular region. Observation of the Russian Wheat Aphid colonies under greenhouse conditions failed to produce males or eggs. In spring 2007, CP was confirmed in a small population of Russian Wheat Aphid that eclosed from eggs (fundatricies) on wild grasses and Wheat near Dove Creek, CO, in the Colorado Plateau region where other Aphid species undergo CP. Lineages from ninety-three fundatricies were screened against 16 resistant and susceptible cereal entries to determine their biotypic classification. A high degree of biotypic diversity (41.4%) was detected in this population. Although CP was a rare in Russian Wheat Aphid populations, genetic recombination during the sexual cycle creates new biotypes and can have significant effects on population genetics.
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plant responses to seven Russian Wheat Aphid hemiptera Aphididae biotypes found in the united states
Journal of Economic Entomology, 2009Co-Authors: Terri L. Randolph, Frank B. Peairs, J B Rudolph, Aubrey A Weiland, Gary J PuterkaAbstract:The Russian Wheat Aphid, Diuraphis noxia (Kurdjumov) (Hemiptera: Aphididae), is a serious Wheat, Triticum aestivum L., and barley, Hordeum vulgare L., pest throughout the small grain-producing areas in the western United States. The virulency and classification of recently described Russian Wheat Aphid biotypes 1–7 (RWA1-7) were clarified using 24 plant differentials. These seven biotypes had been described previously using various methods and test environments; therefore, the purpose of this study was to test them all under uniform environmental conditions. RWA1 was the least virulent of the biotypes tested, with susceptible ratings observed in five plant differentials and intermediate ratings observed in four plant differentials. RWA4, RWA5, RWA6, and RWA7 had intermediate virulence. RWA4, RWA5, and RWA7 share similar responses, with susceptible responses in six plant differentials and intermediate responses in five plant differentials. Small differences within a few plant differentials separate RWA4, RWA5, and RWA7. RWA6 has susceptible responses with only four plant differentials, but 10 plant differentials had intermediate responses. RWA3 was highly virulent, with susceptible responses in 10 plant differentials and intermediate responses in five plant differentials. RWA2 was the most virulent strain tested with susceptible responses to 12 plant differentials and intermediate responses to five plant differentials. This study has demonstrated that RWA1-7 have different combinations of virulence to the plant differentials tested, thereby confirming previous Russian Wheat Aphid biotype designations.
Gary J Puterka - One of the best experts on this subject based on the ideXlab platform.
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change in biotypic diversity of Russian Wheat Aphid hemiptera Aphididae populations in the united states
Journal of Economic Entomology, 2015Co-Authors: Gary J Puterka, Terri L. Randolph, Frank B. Peairs, Scott J Nicholson, M J Brown, Kristopher L Giles, Robert W Hammon, G J Michaels, E D Bynum, T L SpringerAbstract:A key component of Russian Wheat Aphid, Diuraphis noxia (Kurdjumov), management has been through planting resistant Wheat cultivars. A new biotype, RWA2, appeared in 2003 which caused widespread damage to Wheat cultivars containing the Dn4 gene. Biotypic diversity in Russian Wheat Aphid populations has not been addressed since 2005 when RWA2 dominated the biotype complex. Our objectives were to determine the biotypic diversity in the Central Great Plains and Colorado Plateau at regional (2010, 2011, 2013) and local (2012) levels and detect the presence of new Russian Wheat Aphid biotypes. Regional and within-field Aphid collections were screened against Russian Wheat Aphid-resistant Wheat genotypes containing genes Dn3, Dn4, Dn6, Dn7, Dn9, CI2401; and resistant barley STARS 9301B. In 2010, all Aphid collections from Texas were avirulent to the Dn4 resistance gene in Wheat. Regional results revealed Dn4 avirulent RWA6 was widespread (55-84%) in populations infesting Wheat in both regions. Biotypes RWA1, 2, and 3/7 were equally represented with percentages<20% each while RWA8 was rarely detected. Combining percentages of RWA1, 6, and 8 across regions to estimate avirulence to Dn4 gene revealed high percentages for both 2011 (64-80%) and 2013 (69-90%). In contrast, the biotype structure at the local level differed where biotype percentages varied up to ≥2-fold between fields. No new biotypes were detected; therefore, Dn7, CI2401, and STARS9301B remained resistant to all known Russian Wheat Aphid biotypes. This study documents a shift to Dn4 avirulent biotypes and serves as a valuable baseline for biotypic diversity in Russian Wheat Aphid populations prior to the deployment of new Russian Wheat Aphid-resistant Wheat cultivars.
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characterization of eight Russian Wheat Aphid hemiptera Aphididae biotypes using two category resistant susceptible plant responses
Journal of Economic Entomology, 2014Co-Authors: Gary J Puterka, Frank B. Peairs, Scott J Nicholson, M J Brown, W R Cooper, Terri L. RandolphAbstract:ABSTRACT Eight biotypes of the Russian Wheat Aphid, Diuraphis noxia (Kurdjumov), have been discovered in the United States since 2003. Biotypes are identified by the distinct feeding damage responses they produce on Wheat carrying different Russian Wheat Aphid resistance genes, namely, from Dn1 to Dn9. Each Russian Wheat Aphid biotype has been named using plant damage criteria and virulence categories that have varied between studies. The study was initiated to compare the plant damage caused by all the eight known Russian Wheat Aphid biotypes, and analyze the results to determine how Russian Wheat Aphid virulence should be classified. Each Russian Wheat Aphid biotype was evaluated on 16 resistant or susceptible cereal genotypes. Plant damage criteria included leaf roll, leaf chlorosis, and plant height. The distribution of chlorosis ratings followed a bimodal pattern indicating two categories of plant responses, resistant or susceptible. Correlations were significant between chlorosis ratings and leaf ro...
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cyclical parthenogenetic reproduction in the Russian Wheat Aphid hemiptera Aphididae in the united states sexual reproduction and its outcome on biotypic diversity
Journal of Economic Entomology, 2012Co-Authors: Gary J Puterka, John D Burd, Terri L. Randolph, Frank B. Peairs, Robert W Hammon, W R CooperAbstract:In 1986, the Russian Wheat Aphid, Diuraphis noxia (Kurdjumov) (Hemiptera: Aphididae), became an invasive species of United States. Nearly 20 yr later, new biotypes appeared that were capable of overcoming most sources of resistance and became a renewed threat to Wheat, Triticum aestivum L., production. Cyclical (CP) and obligate (OP) parthenogenesis enables Aphids to both adapt to changing environments and exploit host resources. We documented these forms of reproduction for Russian Wheat Aphid in Wheat and wild grasses in the Central Great Plains and Rocky Mountain regions during falls 2004–2009. Colonies from sample sites also were held under unheated greenhouse conditions and observed for the presence of sexual morphs and eggs through the winter. Russian Wheat Aphid populations were mainly OP and attempted to overwinter as adults, regardless of region sampled. A few populations contained oviparae but no males (gynocyclic) and were not specific to any particular region. Observation of the Russian Wheat Aphid colonies under greenhouse conditions failed to produce males or eggs. In spring 2007, CP was confirmed in a small population of Russian Wheat Aphid that eclosed from eggs (fundatricies) on wild grasses and Wheat near Dove Creek, CO, in the Colorado Plateau region where other Aphid species undergo CP. Lineages from ninety-three fundatricies were screened against 16 resistant and susceptible cereal entries to determine their biotypic classification. A high degree of biotypic diversity (41.4%) was detected in this population. Although CP was a rare in Russian Wheat Aphid populations, genetic recombination during the sexual cycle creates new biotypes and can have significant effects on population genetics.
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proteomic analysis of secreted saliva from Russian Wheat Aphid diuraphis noxia kurd biotypes that differ in virulence to Wheat
Journal of Proteomics, 2012Co-Authors: Scott J Nicholson, Steven D Hartson, Gary J PuterkaAbstract:Abstract Diuraphis noxia , Russian Wheat Aphid (RWA), biotypes are classified by their differential virulence to Wheat varieties containing resistance genes. RWA salivary proteins, unlike those of most Aphid species, cause foliar damage and physiological alterations in plants. A comparative proteomic analysis of secreted saliva from four differentially virulent RWA biotypes identified thirty-four individual proteins. The five major proteins were glucose dehydrogenase, lipophorin, chitinase, CiV16.8g1-like, and lava lamp. Fourteen proteins quantitatively varied among biotypes; trehalase, β-N-acetylglucosaminidase (chitinase), two separate glucose dehydrogenases, calreticulin, aminopeptidase, acetylglucosaminyltransferase, hydroxymethylglutaryl-CoA lyase, acyltransferase, ficolin-3, lava lamp, retinaldehyde-binding protein, and two proteins of unknown function. Fifty-four percent of spectral counts were associated with glucose dehydrogenase, which is thought to detoxify plant defensive compounds. One-dimensional electrophoresis detected nine protein bands from 9 to 60 kDa that quantitatively differed. Two-dimensional electrophoresis identified six major gel zones with quantitative and qualitative variance in proteins. Our findings reveal that the salivary proteome of RWA, a phytotoxic Aphid, differs considerably from those reported for nonphytotoxic Aphids. The potential roles of proteins used in the general plant feeding processes of Aphids and those that are potential phytotoxins related to Aphid virulence are discussed.
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plant responses to seven Russian Wheat Aphid hemiptera Aphididae biotypes found in the united states
Journal of Economic Entomology, 2009Co-Authors: Terri L. Randolph, Frank B. Peairs, J B Rudolph, Aubrey A Weiland, Gary J PuterkaAbstract:The Russian Wheat Aphid, Diuraphis noxia (Kurdjumov) (Hemiptera: Aphididae), is a serious Wheat, Triticum aestivum L., and barley, Hordeum vulgare L., pest throughout the small grain-producing areas in the western United States. The virulency and classification of recently described Russian Wheat Aphid biotypes 1–7 (RWA1-7) were clarified using 24 plant differentials. These seven biotypes had been described previously using various methods and test environments; therefore, the purpose of this study was to test them all under uniform environmental conditions. RWA1 was the least virulent of the biotypes tested, with susceptible ratings observed in five plant differentials and intermediate ratings observed in four plant differentials. RWA4, RWA5, RWA6, and RWA7 had intermediate virulence. RWA4, RWA5, and RWA7 share similar responses, with susceptible responses in six plant differentials and intermediate responses in five plant differentials. Small differences within a few plant differentials separate RWA4, RWA5, and RWA7. RWA6 has susceptible responses with only four plant differentials, but 10 plant differentials had intermediate responses. RWA3 was highly virulent, with susceptible responses in 10 plant differentials and intermediate responses in five plant differentials. RWA2 was the most virulent strain tested with susceptible responses to 12 plant differentials and intermediate responses to five plant differentials. This study has demonstrated that RWA1-7 have different combinations of virulence to the plant differentials tested, thereby confirming previous Russian Wheat Aphid biotype designations.