| the reactive oxygen species are involved in resistance responses of wheat to the russian wheat aphid. | the effect of russian wheat aphid (rwa), diuraphis noxia (mordvilko), infestation on the hydrogen peroxide (h(2)o(2)) content and nadph oxidase (ec 1.6.3.1) activity was studied in the resistant (cv. tugela dn) and near-isogenic susceptible (cv. tugela) wheat (triticum aestivum l.). the objective of this study was to investigate the involvement of the reactive oxygen species (ros) during the resistance responses against the rwa. infestation significantly induced an early accumulation of the h(2) ... | 2006 | 17032617 |
| molecular basis of plant gene expression during aphid invasion: wheat pto- and pti-like sequences are involved in interactions between wheat and russian wheat aphid (homoptera: aphididae). | the russian wheat aphid, diuraphis noxia (mordvilko) (homoptera: aphididae), is a major pest of bread wheat, triticum aestivum l. (em thell), in most wheat-growing areas worldwide. aphid-resistant cultivars are used to combat this pest, but very little is known about the molecular basis of resistance. in this study, differential gene expression in d. noxia biotype 1-resistant wheat plants containing the dnx gene and d. noxia biotype 1 feeding on dnx plants was investigated using suppressive subt ... | 2006 | 16937702 |
| positive correlation of fitness with group size in two biotypes of russian wheat aphid (homoptera: aphididae). | changes in fitness parameters as a function of colony size (one versus 10 aphids) were measured in two biotypes (rwa1 and rwa2) of the russian wheat aphid, diuraphis noxia (mordvilko) (homoptera: aphididae), feeding on three cultivars of wheat, triticum aestivum l., at two temperatures. 'trego' is a cultivar with no specific resistance to d. noxia, whereas, 'stanton' and 'halt' express dny and dn4 resistance sources, respectively. feeding in a group accelerated the development of rwa1 on trego a ... | 2006 | 16937675 |
| diuraphis noxia and rhopalosiphum padi (hemiptera: aphididae) interactions and their injury on resistant and susceptible cereal seedlings. | interspecific interactions between the symptomatic (chlorosis-eliciting) russian wheat aphid, diuraphis noxia (mordvilko), and the asymptomatic (nonchlorosis-eliciting) bird cherry-oat aphid, rhopalosiphum padi (l.), on four cereal genotypes were examined by simultaneous infestations. four cereals (i.e., diuraphis noxia-susceptible 'arapahoe' wheat and 'morex' barley, and d. noxia-resistant 'halt' wheat and 'border' oat) and four infestations (i.e., control, d. noxia, r. padi, and d. noxia/r. pa ... | 2006 | 16686159 |
| interactions among three species of cereal aphids simultaneously infesting wheat. | interactions among greenbug, schizaphis graminum (rondani), russian wheat aphid, diuraphis noxia (mordvilko), and bird cherry-oat aphid rhopalosiphum padi (l.) were examined on wheat plants (triticum aestivum l., cultivar tam 107). nymphs were released on the plants as conspecific and heterospecific pairs of either first or fourth instars and evaluated for survival, developmental time, fecundity, intra-plant movement, and affinity to plant tissues. survival from first instar to onset of reproduc ... | 2005 | 16341245 |
| comparison of dn4- and dn7-carrying spring wheat genotypes artificially infested with russian wheat aphid (homoptera: aphididae) biotype 1. | genetic resistance is a useful control strategy for managing russian wheat aphid, diuraphis noxia (mordvilko), in wheat, triticum aestivum l. in 2003, a russian wheat aphid population (denoted as biotype 2) identified in colorado was virulent to genotypes carrying the dn4 russian wheat aphid resistance gene, necessitating the rapid identification and deployment of new sources of resistance. although the dn7 gene had shown excellent resistance to russian wheat aphid biotypes 1 and 2 in evaluation ... | 2005 | 16334342 |
| is photosynthetic transcriptional regulation in triticum aestivum l. cv. 'tugeladn' a contributing factor for tolerance to diuraphis noxia (homoptera: aphididae)? | diuraphis noxia (russian wheat aphid, rwa) is a major pest on wheat in south africa and most other wheat growing countries. being a probing-sucking insect, rwas insert their stylets into the phloem sieve elements and feed on the phloem sap. this feeding causes necrotic lesions in resistant varieties, or decoloration of leaves and death in susceptible varieties. in an effort to broaden our understanding on the response of the plant to rwa feeding, we synthesized and analyzed expressed sequence ta ... | 2006 | 16328390 |
| comparative biology of a novel strain of russian wheat aphid (homoptera: aphididae) on three wheat cultivars. | in spring 2003, several outbreaks of the russian wheat aphid, diuraphis noxia (mordvilko), were reported in fields of supposedly resistant wheat cultivars ('stanton', 'halt', and 'prairie red') in eastern colorado. we conducted two laboratory experiments to compare the biological performance of this new biotype 2 (b2) to that of two d. noxia collections of biotype 1 (b1) from western kansas by using three wheat cultivars as host plants: 'trego', a susceptible cultivar, and stanton and halt, two ... | 2005 | 16022336 |
| resistance to rhopalosiphum padi (homoptera: aphididae) in three triticale accessions. | experiments were conducted to identify and characterize host plant resistance to bird cherry-oat aphid, rhopalosiphum padi (l.), in various wheat and wheat-grass hybrids. initial tests screened for resistance to r. padi among 12 grass accessions (eight wheat [triticum aestivum l.], three triticale [xtriticosecale wittmack], and 1xelytricum [elytrigia elongata [host] nevski x triticum aestivum hybrid]). r. padi had less population growth on triticale accessions '8ta5l' (pi 611760) and 'stniism 3' ... | 2005 | 15889754 |
| genome of russian wheat aphid an economically important cereal aphid. | 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 functioni ... | 2017 | 29299110 |
| diversity and evolution of mariner-like elements in aphid genomes. | although transposons have been identified in almost all organisms, genome-wide information on mariner elements in aphididae remains unknown. genomes of acyrthosiphon pisum, diuraphis noxia and myzus persicae belonging to the macrosiphini tribe, actually available in databases, have been investigated. | 2017 | 28662628 |
| survival and feeding rates of four aphid species (hemiptera: aphididae) on various sucrose concentrations in diets. | different concentrations of sucrose were used to investigate how survival and feeding was affected in four species of aphids (hemiptera: aphididae). seven sucrose concentrations were evaluated in feeding chambers fitted with parafilm membranes and infested with nymphs of aphis glycines matsumura, diuraphis noxia kurdjumov, myzus persicae sulzer, or schizaphis graminum rondani at 25 °c and a photoperiod of 14:10 (l:d) h. survival on each diet was recorded 1, 3, 5, 7, 9, and 11 d. diet volumes (μl ... | 2017 | 28637212 |
| yield response and categories of resistance to russian wheat aphid in four dn4 hard red winter wheat cultivars. | a field experiment was conducted to determine whether resistance to russian wheat aphid, diuraphis noxia (mordvilko), conferred by the dn4 gene is affected by genetic background. this was done by comparing the yield responses to russian wheat aphid-resistant wheat containing dn4, derived through the backcross method, to those of the corresponding recurrent parents. infested resistant cultivars had fewer russian wheat aphids per tiller than infested susceptible cultivars at the lamar and fort col ... | 2005 | 15889752 |
| influence of three resistance sources in winter wheat derived from tam 107 on yield response to russian wheat aphid. | a study to determine yield response to the russian wheat aphid, diuraphis noxia (mordvilko), was conducted during the 1997-1998 and 1998-1999 growing seasons at three eastern colorado locations, akron, fort collins, and lamar, with three wheat lines containing either russian wheat aphid-resistant dn4 gene, dn6 gene, or resistance derived from pi 222668, and tam 107 as the susceptible control. russian wheat aphids per tiller were greater on tam 107 than the resistant wheat lines at the 10x infest ... | 2005 | 15889729 |
| field evaluation of emmer wheat-derived synthetic hexaploid wheat for resistance to russian wheat aphid (homoptera: aphididae). | broadening the genetic base for resistance to russian wheat aphid, diuraphis noxia (mordvilko) (homoptera: aphididae), in bread wheat, triticum aestivum l., is desirable. to date, identified russian wheat aphid resistance genes are either located to the d chromosomes or to rye translocation of wheat, and resistance derived from the a or b genomes of tetraploid triticum spp. would therefore be highly beneficial. fifty-eight synthetic hexaploid wheat, derived from interspecific crosses of triticum ... | 2004 | 15279292 |
| enzymatic chlorophyll degradation in wheat near-isogenic lines elicited by cereal aphid (homoptera: aphididae) feeding. | chlorophyll degradation enzyme (i.e., chlorophyllase, mg-dechelatase, and chlorophyll oxidase) activities of aphid-infested and uninfested 'tugela' and tugela near-isogenic wheat lines (i.e., tugela-dn1, tugela-dn2, and tugela-dn5) were assayed. chlorophyllase activity was higher in bird cherry-oat aphid, rhopalosiphum padi (l.) (homoptera: aphididae),-infested wheat lines compared with russian wheat aphid, diuraphis noxia (mordvilko) (homoptera: aphididae)]-infested and uninfested plants. mg-de ... | 2004 | 15154496 |
| aphid (hemiptera: aphididae) resistance in wheat near-isogenic lines. | plant and aphid biomass, photosynthetic pigment (chlorophylls a and b and carotenoids) concentrations, and chlorophyll a/b and chlorophyll/carotenoid ratios were quantified in aphid-infested 'tugela' near-isogenic lines (tugela, tugela-dn1, tugela-dn2, and tugela-dn5). the objectives were to quantify changes of photosynthetic pigments (chlorophylls a and b, and carotenoids) caused by aphid feeding and assess resistance of wheat isolines through aphid and plant biomass analysis. biomass of bird c ... | 2004 | 15154494 |
| comparison of chlorophyll and carotenoid concentrations among russian wheat aphid (homoptera: aphididae)-infested wheat isolines. | russian wheat aphid, diuraphis noxia (mordvilko), feeding injury on 'betta' wheat isolines with the dn1 and dn2 genes was compared by assessing chlorophyll and carotenoid concentrations, and aphid fecundity. the resistant betta isolines (i.e., betta-dn1 and betta-dn2) supported similar numbers of aphids, but had significantly fewer than the susceptible betta wheat, indicating these lines are resistant to aphid feeding. diuraphis noxia feeding resulted in different responses in total chlorophyll ... | 2003 | 14994818 |
| plant damage and yield response to the russian wheat aphid (homoptera: aphididae) on susceptible and resistant winter wheats in colorado. | plant damage and yield response to the russian wheat aphid, diuraphis noxia (mordvilko), were evaluated on a susceptible (tam 107) and a resistant (rwa e1) winter wheat, triticum aestivum l., in three colorado locations in the 1993 and 1994 crop years. russian wheat aphid was more abundant on tam 107 than on rwa e1. russian wheat aphid days per tiller were greater at the higher infestation levels. yield losses as a result of russian wheat aphid infestation occurred most of the time with tam 107 ... | 2003 | 14994801 |
| genetic variation and founder effects in the parasitoid wasp, diaeretiella rapae (m'intosh) (hymenoptera: braconidae: aphidiidae), affecting its potential as a biological control agent. | the effects of recent colonization on the aphid parasitoid, diaeretiella rapae (m'intosh) (hymenoptera: braconidae: aphidiidae), in western australia were investigated. when compared with populations from the old world, the results of a microsatellite analysis show that the insects have low allelic length and low allele frequency variation, revealing that these individuals experienced a significant founder effect. marked genetic differentiation between populations was also revealed, which has po ... | 2003 | 14629347 |
| categories of resistance at four growth stages in three wheats resistant to the russian wheat aphid (homoptera: aphididae). | laboratory experiments were conducted to determine categories of resistance to russian wheat aphid, diuraphis noxia (mordvilko), in three wheats, triticum aestivum l, (pi 372129, pi 243781, and pi 222668) at zadoks growth stages 10, 20, 30, and 40. 'tam 107' was used as the susceptible standard. antixenosis was observed in pi 222668 and pi 372129. antibiosis was expressed as reduced nymphipositional period, daily nymph production, and fecundity at the jointing (zadoks 30) and boot (zadoks 40) st ... | 2003 | 12852604 |
| categories of resistance at different growth stages in halt, a winter wheat resistant to the russian wheat aphid (homoptera: aphididae). | this study was designed to categorize the resistance to the russian wheat aphid, diuraphis noxia (mordvilko), resistant hard red winter wheat, halt, as compared with susceptible wheat, tam 107, at four different growth stages. antixenosis was expressed in halt at growth stage zadoks 30. antibiosis in halt affected fecundity, number of aphids produced per reproductive day, maximum number of nymphs produced in one day, and intrinsic rate of increase. fecundity was lower on halt than tam 107, and m ... | 2003 | 12650365 |
| light activation of russian wheat aphid-elicited physiological responses in susceptible wheat. | the impact of light and its role in russian wheat aphid, diuraphis noxia (mordvilko), damage symptom formation, and photosynthetic capacity in 'arapahoe' wheat (triticum aestivum l.) were examined. after 72 h under continuous dark or continuous light regimes, the number of aphids (nymphs), leaf rolling and chlorosis ratings, fresh leaf weight, and chlorophyll contents were recorded. photosynthetic rates, chlorophyll a, kinetics and chlorophyll extractions also were determined. aphid infestation ... | 2003 | 12650362 |
| identification of microsatellite markers linked to russian wheat aphid resistance genes dn4 and dn6. | the russian wheat aphid (rwa), diuraphis noxia (mordvilko), is a serious economic pest of wheat worldwide. host plant resistance is the preferred method to control rwa infestations. the identification and mapping of rwa-resistant genes and the development of resistant wheat cultivars can be facilitated through the use of molecular markers. in the present study, microsatellite (ssr) markers linked to the rwa-resistant genes dn4 and dn6 were identified using several f(2) mapping populations derive ... | 2002 | 12582610 |
| glycoproteins from russian wheat aphid infested wheat induce defence responses. | elicitors are molecules which can induce the activation of plant defence responses. elicitor activity of intercellular wash fluid from russian wheat aphid, diuraphis noxia (mordvilko) infested resistant (cv tugela dn), and susceptible (cv tugela), wheat (triticum aestivum l.), was investigated. known russian wheat aphid resistance related responses such as peroxidase and beta-1,3-glucanase activities were used as parameters of elicitor activity. the intercellular wash fluid from infested resista ... | 2009 | 12440726 |
| physiological modification of the host feeding site by cereal aphids (homoptera: aphididae). | indole-3-acetic acid-l-14c and 14c-sucrose labels were used to study the effects of greenbugs, schizaphis graminum (rondani), and russian wheat aphids, diuraphis noxia (mordvilko), on phloem function of wheat (triticum aesticum l.). greenbug feeding significantly reduced translocation from the immediate feeding site; however, phloem integrity was not impeded. in contrast, russian wheat aphids had little effect on vein loading or phloem translocation at the feeding site. similar results were obta ... | 2002 | 12020028 |
| registration of three wheat germplasms resistant to diuraphis noxia. | | 2002 | 11756312 |
| relative suitability of crested wheatgrass and other perennial grass hosts for the russian wheat aphid (homoptera: aphididae). | the russian wheat aphid, diuraphis noxia (mordvilko) (homoptera: aphididae), reproduces parthenogenetically in north america and must survive year-round on host plants, including in late summer when small grains are not in cultivation. during this time, cool-season perennial wheatgrasses (poaceae: triticeae) contribute substantially to aphid survival, crested wheatgrass (agropyron spp.) particularly. in greenhouse studies, the number of aphids per plant was measured after four infestation period ... | 2000 | 10826180 |
| an early indicator of resistance in barley to russian wheat aphid. | during early stages of infestation by russian wheat aphids (diuraphis noxia [mordvilko]; rwas), barley (hordeum vulgare l.) leaf cells collapsed and showed autofluorescence in the mesophyll and bundle sheath adjacent to the rwa stylet sheath. the response was visually similar to the hypersensitive cell death response, typical of resistance to microbial pathogens. resistant barley produced significantly more collapsed, autofluorescent cells (cac) than did susceptible barley. rwa stylet entry site ... | 1994 | 12232285 |
| in vitro selection for russian wheat aphid (diuraphis noxia) resistance in wheat (triticum aestivum). | the russian wheat aphid (diuraphis noxia) is a pest on wheat (triticum aestivum) in many regions of the world. the aphid injects a phytotoxin when it feeds. identification of somaclonal variants with phytotoxin resistance may shorten development time for resistance. wheat calli from the susceptible cultivar 'stephens' were exposed to an extract from the aphid. five plants were regenerated from 100 treated calli. resistance to the aphid was observed in both the r2 and r3 generations. one of the s ... | 1993 | 24197254 |
| a large-scale field study of bacterial communities in cereal aphid populations across morocco. | insects are frequently associated with bacteria that can have significant ecological and evolutionary impacts on their hosts. to date, few studies have examined the influence of environmental factors to microbiome composition of aphids. the current work assessed the diversity of bacterial communities of five cereal aphid species (sitobion avenae, rhopalosiphum padi, r. maidis, sipha maydis and diuraphis noxia) collected across morocco and covering a wide range of environmental conditions. we aim ... | 2018 | 29346623 |
| retraction: virulent diuraphis noxia aphids over-express calcium signaling proteins to overcome defenses of aphid-resistant wheat plants. | | 2018 | 29346432 |
| rapid cold hardening capacity and its impact on performance of russian wheat aphid (hemiptera: aphididae). | the russian wheat aphid, diuraphis noxia (kurdjumov), is one of the most important pests of wheat and barley in most wheat-producing countries. rapid cold hardiness (rch) is a capacity of insects to develop, within hours, protection against subfreezing temperatures that plays an important role in aphid survival in response to sudden decreases in air temperature. in this research, we investigated the duration and rate of cooling on the induction of rch of d. noxia and the costs of rch on aphid de ... | 2017 | 28541434 |
| inheritance and categories of resistance in wheat to russian wheat aphid (hemiptera: aphididae) biotype 1 and biotype 2. | the russian wheat aphid, diruaphis noxia (kudjumov) (hemiptera: aphididae), is globally one of the most devastating pests of wheat, tritium aestivum l., and barley, hordeum vulgare l. host plant resistance is the foundation of cereal insect pest management programs, and several d. noxia resistance (dn) genes from wheat have been introduced in commercial cultivars of wheat to manage russian wheat aphid (rwa). emergence of d. noxia biotype 2 (rwa2) in colorado has made all known dn genes, except t ... | 2009 | 19736781 |
| evaluation of tolerance of 20 wheat cultivars to russian wheat aphid diuraphis noxza (mordvilko) at seedling stage under greenhouse conditions. | the russian wheat aphid (r.w.a) is an aggressive pest of wheat, barley and other small grains in different parts of the world and during, the recent years in iran. this aphid causes high damage, so that much insecticides have been used against it. at present time utilization of resistant varieties is one of the most important methods to control it. therefore in order to evaluate the tolerance of 20 wheat cultivars, seeds were planted in 18 cm diameter plastic pots and put in cages. one week afte ... | 2003 | 15149118 |
| biological control of cereal aphids in north america and mediating effects of host plant and habitat manipulations. | the predator and parasitoid fauna associated with cereal aphids is described, emphasizing the fauna associated with classical biological control efforts against the greenbug and russian wheat aphid. we focus on literature from north america and include work from europe and elsewhere when it is desirable to draw contrasts between approaches that affect cereal aphid biological control. effects on natural enemies of cereal aphids are described that appear associated with plant traits that are innat ... | 2004 | 14651463 |
| genetic mapping of dn7, a rye gene conferring resistance to the russian wheat aphid in wheat. | the russian wheat aphid is a significant pest problem in wheat and barley in north america. genetic resistance in wheat is the most effective and economical means to control the damage caused by the aphid. dn7 is a rye gene located on chromosome 1rs that confers resistance to the russian wheat aphid. the gene was previously transferred from rye into a wheat background via a 1rs/1bl translocation. this study was conducted to genetically map dn7 and to characterize the type of resistance the gene ... | 2003 | 12879254 |
| homoeologous set of nbs-lrr genes located at leaf and stripe rust resistance loci on short arms of chromosome 1 of wheat. | homoeologous group 1 chromosomes of wheat contain important genes that confer resistance to leaf, stem and stripe rusts, powdery mildew and russian wheat aphid. a disease resistance gene analog encoding nucleotide binding site-leucine rich repeat (nbs-lrr), designated rgayr10, was previously identified at the stripe rust resistant locus, yr10, located on chromosome 1bs distal to the storage protein, gli-b1locus. rgayr10 identified gene members in the homoeologous region of chromosome 1ds cosegre ... | 2003 | 12590346 |
| isolation of early-responsive microrna from diuraphis noxia (hemiptera: aphididae)-resistant wheat. | the russian wheat aphid (diuraphis noxia kurdjumov) is an economically important pest of small grains in many countries. the past decades have seen the deployment of resistance-carrying wheat (triticum aestivum l.) cultivars to control d. noxia. however, the emergence of resistance-breaking biotypes is negating this strategy. the role that noncoding rna (ncrna) molecules play in the wheat-d. noxia interaction has not been studied to date. this study aimed to isolate differentially regulated micr ... | 2017 | 28407081 |
| chromosomal genomics facilitates fine mapping of a russian wheat aphid resistance gene. | 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 enabli ... | 2015 | 25862680 |
| bac libraries from wheat chromosome 7d: efficient tool for positional cloning of aphid resistance genes. | positional cloning in bread wheat is a tedious task due to its huge genome size and hexaploid character. bac libraries represent an essential tool for positional cloning. however, wheat bac libraries comprise more than million clones, which makes their screening very laborious. here, we present a targeted approach based on chromosome-specific bac libraries. such libraries were constructed from flow-sorted arms of wheat chromosome 7d. a library from the short arm (7ds) consisting of 49,152 clones ... | 2011 | 21318113 |
| variation of resistance in barley against biotypes 1 and 2 of the russian wheat aphid (hemiptera: aphididae). | the russian wheat aphid, diruaphis noxia (kurdjumov) (hemiptera: aphididae), is globally one of the most devastating pests of bread wheat, tritium aestivum l.; durum wheat, triticum turgidum l.; and barley, hordeum vulgare l. host plant resistance is the foundation for cereal insect pest management programs, and several sources of d. noxia resistance have been incorporated in cultivars to manage d. noxia damage. the emergence of d. noxia north american biotype 2 (rwa2) in colorado has made all k ... | 2010 | 20568641 |
| microsatellite-based molecular diversity of bread wheat germplasm and association mapping of wheat resistance to the russian wheat aphid. | genetic diversity of a set of 71 wheat accessions, including 53 biotype 2 russian wheat aphid (rwa2)-resistant landraces and 18 rwa2 susceptible accessions, was assessed by examining molecular variation at multiple microsatellite (ssr) loci. fifty-one wheat ssr primer pairs were used, 81 ssr loci were determined, and 545 ssr alleles were detected. these ssr loci covered all the three genomes, 21 chromosomes, and at least 41 of the 42 chromosome arms. diversity values averaged over ssr loci were ... | 2009 | 18392559 |
| characterisation of triticum vavilovii-derived stripe rust resistance using genetic, cytogenetic and molecular analyses and its marker-assisted selection. | stripe rust resistance was identified in triticum vavilovii( t. vaviloviiaus22498)-derived russian wheat aphid (rwa)-resistant germplasm. inheritance studies indicated monogenic control of resistance. the resistance gene was tentatively designated as yrvav and was located on chromosome 1b by monosomic analysis. a close association (1.5+/-0.9% recombination) of yrvav with a t. vavilovii-derived gliadin allele ( gli-b1vav) placed it in chromosome arm 1bs. yrvavwas allelic with yr10. tests with yr1 ... | 2002 | 12582703 |