| isolation of a novel collagen gene (mj-col-5) in meloidogyne javanica and analysis of its expression pattern. | mj-col-5, isolated from the plant parasitic nematode meloidogyne javanica, has a longer carboxy-terminus than other members of the caenorhabditis elegans col-6 subfamily of cuticle collagen, including an extra tyrosine residue, and may form altered nonreducible cross-linkages. by semiquantitative determination at different life stages, mj-col-5 transcript was shown to be more abundant in eggs than in juveniles/young females and adult females. to characterize further this gene's contribution to t ... | 2001 | 11534644 |
| fungal parasites of the cereal cyst nematode heterodera avenae in southern sweden. | fungal parasites of the cereal cyst nematode heterodera avenae were isolated from four sites in southern sweden. in all, 15 different fungi were isolated from different stages of the nematode life cycle. among the egg parasites, verticillium chlamydosporium was common in young cysts on roots, whereas an unidentified species of verticillium (verticillium sp. 1) was the dominating species in cysts from soil, especially if the soll had been stored for 8-12 months. v. chlamydosporium was frequently ... | 1985 | 19294057 |
| world dissemination of the cereal-cyst nematode (heterodera avenae) and its potential as a pathogen of wheat. | world distribution of the cereal-cyst nematode is herein reviewed. it is suggested that heterodera avenae originated in europe and has been widely disseminated, largely by the activities of man but also by wind movement of cysts. so far, it may not have spread to some major wheat-growing regions of the new world, but a non-friable soil structure limits population level and disease. yield loss could result from the introduction of new cultivars to developing countries where h . avenae has not bee ... | 1977 | 19305564 |
| association analysis of resistance to cereal cyst nematodes (heterodera avenae) and root lesion nematodes (pratylenchus neglectus and p. thornei) in cimmyt advanced spring wheat lines for semi-arid conditions. | to identify loci linked to nematode resistance genes, a total of 126 of cimmyt advanced spring wheat lines adapted to semi-arid conditions were screened for resistance to heterodera avenae, pratylenchus neglectus, and p. thornei, of which 107 lines were genotyped with 1,310 dart. association of dart markers with nematode response was analyzed using the general linear model. results showed that 11 markers were associated with resistance to h. avenae (pathotype ha21), 25 markers with resistance to ... | 2016 | 28163585 |
| molecular characterization of a novel effector expansin-like protein from heterodera avenae that induces cell death in nicotiana benthamiana. | cereal cyst nematodes are sedentary biotrophic endoparasites that maintain a complex interaction with their host plants. nematode effector proteins are synthesized in the oesophageal glands and are secreted into plant tissues through the stylet. to understand the function of nematode effectors in parasitic plants, we cloned predicted effectors genes from heterodera avenae and transiently expressed them in nicotiana benthamiana. infiltration assays showed that haexpb2, a predicted expansin-like p ... | 2016 | 27808156 |
| correction: characterization of three novel fatty acid- and retinoid-binding protein genes (ha-far-1, ha-far-2 and hf-far-1) from the cereal cyst nematodes heterodera avenae and h. filipjevi. | [this corrects the article doi: 10.1371/journal.pone.0160003.]. | 2016 | 27764248 |
| comparative analysis of pre- and post-parasitic transcriptomes and mining pioneer effectors of heterodera avenae. | the cereal cyst nematode (ccn, heterodera avenae) is a devastating pathogen of wheat and barley crops in many countries. we aimed to prioritize genetic and molecular targets for h. avenae control via the powerful and integrative bioinformatics platform. | 2017 | 28289537 |
| morphological and morphometrical analysis of heterodera spp. populations in jordan. | phenotypic diversity of five jordanian populations of cyst nematodes, heterodera spp. collected from five regions from jordan (ar-ramtha, madaba, dana, al-karak, and jerash) was investigated. soil samples were collected from one representative field in each region. morphological and morphometrical characteristics revealed that heterodera latipons is dominated in cereal fields at ar-ramtha, madaba, dana and al-karak regions and heterodera schachtii in jerash. cysts populations from all cereal fie ... | 2016 | 26858546 |
| de novo transcriptome sequencing and analysis of the cereal cyst nematode, heterodera avenae. | the cereal cyst nematode (ccn, heterodera avenae) is a major pest of wheat (triticum spp) that reduces crop yields in many countries. cyst nematodes are obligate sedentary endoparasites that reproduce by amphimixis. here, we report the first transcriptome analysis of two stages of h. avenae. after sequencing extracted rna from pre parasitic infective juvenile and adult stages of the life cycle, 131 million illumina high quality paired end reads were obtained which generated 27,765 contigs with n ... | 2014 | 24802510 |
| isolation and characterization of a fatty acid- and retinoid-binding protein from the cereal cyst nematode heterodera avenae. | a gene encoding fatty acid- and retinoid-binding protein was isolated from the cereal cyst nematode heterodera avenae and the biochemical function of the protein that it encodes was analysed. the full-length cdna of the ha-far-1 gene is 827 bp long and includes a 22- nucleotide trans-spliced leader sequence (sl1) at its 5-end. the genomic clone of ha-far-1 consists of eight exons separated by seven introns, which range in size from 48 to 186 bp. the ha-far-1 cdna contains an open reading frame e ... | 2016 | 27240755 |
| characterization of three novel fatty acid- and retinoid-binding protein genes (ha-far-1, ha-far-2 and hf-far-1) from the cereal cyst nematodes heterodera avenae and h. filipjevi. | heterodera avenae and h. filipjevi are major parasites of wheat, reducing production worldwide. both are sedentary endoparasitic nematodes, and their development and parasitism depend strongly on nutrients obtained from hosts. secreted fatty acid- and retinol-binding (far) proteins are nematode-specific lipid carrier proteins used for nutrient acquisition as well as suppression of plant defenses. in this study, we obtained three novel far genes ha-far-1 (ku877266), ha-far-2 (ku877267), hf-far-1 ... | 2016 | 27479008 |
| inducible flavone in oats (avena sativa) is a novel defense against plant-parasitic nematodes. | abstract the induction of defense compounds in oats (avena sativa) in response to invasion by parasitic nematodes and to application of the wound hormone methyl jasmonate was examined. oats cv. quoll seedlings were challenged with pratylenchus neglectus, heterodera avenae, and ditylenchus dipsaci and treated with 1 x 10(-4) m methyl jasmonate. three compounds, isolated in methanolic root and shoot extracts of oats, exhibiting an absorbance spectrum typical of flavone glycosides, were induced by ... | 2004 | 18944456 |
| an annexin-like protein from the cereal cyst nematode heterodera avenae suppresses plant defense. | parasitism genes encoding secreted effector proteins of plant-parasitic nematodes play important roles in facilitating parasitism. an annexin-like gene was isolated from the cereal cyst nematode heterodera avenae (termed ha-annexin) and had high similarity to annexin 2, which encodes a secreted protein of globodera pallida. ha-annexin encodes a predicted 326 amino acid protein containing four conserved annexin domains. southern blotting revealed that there are at least two homologies in the h. a ... | 2015 | 25849616 |
| large-scale identification of wheat genes resistant to cereal cyst nematode heterodera avenae using comparative transcriptomic analysis. | cereal cyst nematode heterodera avenae, an important soil-borne pathogen in wheat, causes numerous annual yield losses worldwide, and use of resistant cultivars is the best strategy for control. however, target genes are not readily available for breeding resistant cultivars. therefore, comparative transcriptomic analyses were performed to identify more applicable resistance genes for cultivar breeding. | 2015 | 26475271 |
| effect of different potting systems; inoculation time; nematode density and sources of cereal cyst nematode (heterodera filipjevi) on juvenile penetration into wheat root system. | investigations were designed to optimize testing systems for screening wheat breeding lines for resistance to heterodera filipjevi. the effects of: 1) plant potting systems 2) inoculum level and time of inoculation 3) and type of inoculum of h. filipjevi on detection accuracy were examined in growth chamber experiments in turkey. the rate of nematode penetration in the highly susceptible variety bezostaya was used as the base measurement of efficacy. the results showed that the highest level of ... | 2010 | 21539268 |
| molecular aspects of cyst nematodes. | summary taxonomy: superkingdom eukaryota; kingdom metazoa; phylum nematoda; class chromadorea; order tylenchida; suborder tylenchina; superfamily tylenchoidea; family heteroderidae; subfamily heteroderinae; main genera heterodera and globodera. host range: cyst nematodes comprise approximately 100 known species in six genera. they are pathogens of temperate, subtropical and tropical plant species and the host range of many species is narrow. the most economically important species are within the ... | 2005 | 20565681 |
| nematicide seed dressing for cyst and lesion nematode control in wheat. | a trial was conducted in the northern negev region of israel in a field heavily infested with both cyst (heterodera avenae) and lesion (pratylenchus mediterraneus) nematodes. wheat (triticum aestivum cv. bet lehem) seeds were coated with either seed-dressing formulation of furathiocarb 10 g a.i./kg seed or emulsifiable concentrate formulations ofcarbofuran 10 g a.i./kg seed or oxamyl 3.6 g a.i./kg seed. untreated seeds served as control. the trial was arranged in a randomized block design with s ... | 1989 | 19287661 |
| damage to italian crops caused by cyst-forming nematodes. | investigations were undertaken in 1982-88 to estimate yield losses of carrot, sugarbeet, wheat, and potato caused by cyst-forming nematodes (heterodera and globodera species) in several provinces of italy. soil samples were collected at planting in 0.5-ha sampling areas distributed in each crop's major production area. yield loss estimates were based on nematode population estimates and on curves derived earlier relating nematode densities with crop yields in italy. estimated yield loss values w ... | 1993 | 19279850 |
| molecular polymorphism and morphometrics of species of the heterodera avenae group in syria and turkey. | molecular characterization of the three most common cereal cyst nematode species of the heterodera avenae group (h. avenae, h. filipjevi, and h. latipons), originating from various locations in major cereal-cultivating areas in syria and turkey, showed distinct restriction fragment patterns of the its-rdna following pcr amplification and rflp digestion with four endonucleases (hae iii, hinf i, ita i, and pst i). genetic dissimilarity within h. avenae group populations increased in comparison wit ... | 2005 | 19262854 |
| nematodes in dryland field crops in the semiarid pacific northwest united states. | soils and roots of field crops in low-rainfall regions of the pacific northwest were surveyed for populations of plantparasitic and non-plant-parasitic nematodes. lesion nematodes (pratylenchus species) were recovered from 123 of 130 non-irrigated and 18 of 18 irrigated fields. pratylenchus neglectus was more prevalent than p. thornei, but mixed populations were common. population densities in soil were affected by crop frequency and rotation but not by tillage or soil type (p < 0.05). many fiel ... | 2004 | 19262788 |
| morphology and morphometrics of heterodera filipjevi (madzhidov, 1981) steller, 1984 from kohgiluyeh and boyer-ahmad province, iran. | during 2007 and 2008, soil samples of wheat and barley fields of the cold regions of the kohgiluyeh and boyer-ahmad province were surveyed for cereal cyst nematode. in 65% of samples cysts were seen. morphological and morphometrics of cysts, cone top structure and second stage juveniles of the isolated populations were studied. detailed taxonomic studies revealed the existence of h. filipjevi. this is the first report of the species in the province. | 2008 | 18817233 |
| cereal cyst nematode resistance conferred by the cre7 gene from aegilops triuncialis and its relationship with cre genes from australian wheat cultivars. | cereal cyst nematode (ccn; heterodera avenae woll.) is a root pathogen of cereal crops that can cause severe yield losses in wheat (triticum aestivum). differential host-nematode interactions occur in wheat cultivars carrying different ccn resistance (cre) genes. the objective of this study was to determine the ccn resistance conferred by the cre7 gene from aegilops triuncialis in a 42-chromosome introgression line and to assess the effects of the cre1, cre3, cre4, and cre8 genes present in aust ... | 2008 | 18438434 |
| the global importance of the cereal cyst nematode (heterodera spp.) on wheat and international approaches to its control. | the cereal cyst nematodes (ccns) are a group of several closely related species which have been documented to cause economic yield loss on rainfed wheat production systems in several part of the world including north africa, west asia, china, india, australia, america and several countries in europe. the most commonly reported species is heterodera avenae, however there are at least two other species h. filipjevi and h. latipons are implicated. it is well appreciated that plants under water and ... | 2007 | 18399504 |
| assessment of nematode resistance in wheat transgenic plants expressing potato proteinase inhibitor (pin2) gene. | serine proteinase inhibitors (ip's) are proteins found naturally in a wide range of plants with a significant role in the natural defense system of plants against herbivores. the question addressed in the present study involves assessing the ability of the serine proteinase inhibitor in combating nematode infestation. the present study involves engineering a plant serine proteinase inhibitor (pin2) gene into t. durum pdw215 by agrobacterium-mediated transformation to combat cereal cyst nematode ... | 2005 | 16245157 |
| fungal egg-parasites of plant-parasitic nematodes from spanish soils. | we have investigated the presence of fungal egg-parasites in spanish soils with plant endoparasitic nematodes. nine out of 68 samples (13%) yielded fungal parasites. the most common (seven strains) was pochonia chlamydosporia var. chlamydosporia (= verticillium chlamydosporium var. chlamydosporium), but lecanicillium lecanii (= verticillium lecanii) and paecilomyces lilacinus were also found. most strains were from cyst nematodes (heterodera avenae or heterodera schachtii). biological factors re ... | 2002 | 12828513 |
| a new hessian fly resistance gene (h30) transferred from the wild grass aegilops triuncialis to hexaploid wheat. | a new hessian fly (mayetiola destructor say) resistance gene from aegilops triuncialis and its transfer to hexaploid wheat via interspecific hybridisation is described. the transfer line tr-3531 (42 chromosomes), derived from the cross [(triticum turgidum x ae. triuncialis) x triticum aestivum] and carrying the heterodera avenae resistance gene cre7, showed a high level of resistance to the m. destructor biotype prevailing in the sw of spain. a single dominant gene (h30) seems to determine the h ... | 2003 | 12748776 |
| tylenchida associated with field crops in tehran and central provinces of iran. | on a survey of plant parasitic nematodes, belonging to the order tylenchida, about 500 soil and root samples were collected from different field crops, such as wheat, barley, tomato, potato, corn, beets, eggplants, cuccumber, melon and also other crops cultivated in tehran and central provinces during 1995-2000. all samples were washed and the nematodes were extracted by centrifugal flotation technique. they were fixed and transferred to glycerin, then permanent slides were mounted. morphologica ... | 2002 | 12696441 |
| occurrence and diversity of egg pathogenic fungi of the mediterranean cereal cyst nematode heterodera latipons. | eighteen fungal strains in nine genera present in german and syrian soils were isolated from eggs of the barley cyst nematode h. latipons. the fungi were selected out of the soil microflora using the slide-frame baiting technique from a semiarid soil originating from syria heavily infested with h. latipons and from a temperate soil from german heavily infested with h. schachtii. fusarium and acremonium were the most common fungi isolated from the both soils. the natural suppressiveness or antago ... | 2001 | 12425089 |
| resistance gene analogs within an introgressed chromosomal segment derived from triticum ventricosum that confers resistance to nematode and rust pathogens in wheat. | a resistance (r) gene-rich 2s chromosomal segment from triticum ventricosum contains a cereal cyst nematode (ccn; heterodera avenae) r gene locus crex and a closely linked group of genes (sr38, yr17, and lr37) that confer resistance to stem rust (puccinia graminis f. sp. tritici), stripe rust (p. striiformis f. sp. tritici), and leaf rust (p. recondita f. sp. tritici) when introgressed into wheat. the 2s chromosomal segment from t. ventricosum is further delineated in translocations onto chromos ... | 2000 | 10707359 |
| identification and in situ and in vitro characterization of secreted proteins produced by plant-parasitic nematodes. | secretions of plant-parasitic nematodes which are released into plant tissue may play critical roles in plant-nematode interactions. the identification and characterization of these molecules are of fundamental importance and may help to facilitate the development of novel strategies to interfere with nematode infection of plants and thereby decrease nematode-induced damage to crops. an antibody-based approach was used to isolate molecules present on the nematode surface and in nematode secretio ... | 1996 | 8939056 |
| carbohydrate-recognition domains on the surface of phytophagous nematodes. | human red blood cells (hrbc) adhered to preparasitic second-stage juveniles (j2) of heterodera avenae, heterodera schachtii, meloidogyne javanica, pratylenchus mediterraneus, rotylenchulus reniformis, and tylenchulus semipenetrans over the entire nematode body. binding was conspicuously confined to the head and tail of longidorus cohni, xiphinema brevicolle, and xiphinema index. binding was ca2+ and mg2+ dependent. in contrast, hrbc did not adhere to anguina tritici, aphelenchoides subtenius, di ... | 1995 | 7895833 |
| genome-wide association study in wheat identifies resistance to the cereal cyst nematode heterodera filipjevi. | the cyst nematode heterodera filipjevi is a plant parasite causing substantial yield loss in wheat. resistant cultivars are the preferred method of controlling cyst nematodes. association mapping is a powerful approach to detect associations between phenotypic variation and genetic polymorphisms; in this way favorable traits such as resistance to pathogens can be located. therefore, a genome-wide association study of 161 winter wheat accessions was performed with a 90k iselect single nucleotide ... | 2016 | 27552283 |
| rna-seq based identification of candidate parasitism genes of cereal cyst nematode (heterodera avenae) during incompatible infection to aegilops variabilis. | one of the reasons for the progressive yield decline observed in cereals production is the rapid build-up of populations of the cereal cyst nematode (ccn, heterodera avenae). these nematodes secrete so-call effectors into their host plant to suppress the plant defense responses, alter plant signaling pathways and then induce the formation of syncytium after infection. however, little is known about its molecular mechanism and parasitism during incompatible infection. to gain insight into its rep ... | 2015 | 26517841 |
| the dynamics of cereal cyst nematode infection differ between susceptible and resistant barley cultivars and lead to changes in (1,3;1,4)-β-glucan levels and hvcslf gene transcript abundance. | heterodera avenae (cereal cyst nematode, ccn) infects the roots of barley (hordeum vulgare) forming syncytial feeding sites. in resistant host plants, relatively few females develop to maturity. little is known about the physiological and biochemical changes induced during ccn infection. responses to ccn infection were investigated in resistant (rha2) and susceptible barley cultivars through histological, compositional and transcriptional analysis. two phases were identified that influence ccn v ... | 2015 | 25737227 |
| [lethal effects of trichoderma longibrachiatum on heterodera avenae]. | the lethal effect of the conidia suspension of trichoderma longibrachiatum against second stage juveniles of heterodera avenae was observed under microscopic conditions and studied in vitro to preliminarily determine the potential and mechanism of the conidia suspension of t. longibrachiatum against h. avenae. microscopic observation results showed that the conidia suspension of t. longibrachiatum adhered to or parasitized on the surface of second stage juveniles, even some parasitized nematodes ... | 2014 | 25345063 |
| [parasitic and lethal action of trichoderma longibrachiatum against heterodera avenae]. | to evaluate the potential of trichoderma longibrachiatum spore suspension against heterodera avenae. | 2014 | 25252461 |
| discrimination of plant-parasitic nematodes from complex soil communities using ecometagenetics. | many plant pathogens are microscopic, cryptic, and difficult to diagnose. the new approach of ecometagenetics, involving ultrasequencing, bioinformatics, and biostatistics, has the potential to improve diagnoses of plant pathogens such as nematodes from the complex mixtures found in many agricultural and biosecurity situations. we tested this approach on a gradient of complexity ranging from a few individuals from a few species of known nematode pathogens in a relatively defined substrate to a c ... | 2014 | 24915429 |
| structural and functional analysis of cathepsin s of heterodera spp: a promising candidate for its control. | cysteine proteinases are required for a wide range of physiological processes in all living organisms. in parasitic nematodes, they are particularly crucial for the digestion of host tissues and evasion of host immune responses. therefore, in general, these are identified as primary targets for the control of parasitic nematodes. herein, cathepsin s-like cysteine proteinase of heterodera avenae (hacp-s) has been cloned and analysed for the first time. the predicted protein is 298 amino acids lon ... | 2014 | 24669665 |
| effect of urea and certain npk fertilizers on the cereal cyst nematode (heterodera avenae) on wheat. | two outdoor pot experiments were conducted in two consecutive years under outdoor conditions during the wheat growing season in saudi arabia to determine the effects of urea and certain compound fertilizers (npk), compared to the effects of the nematicide fenamiphos on the cereal cyst nematode (ccn), heterodera avenae, and wheat growth. the results showed that all of the treatments, except the fertilizer diammonium phosphate (dap), reduced the number of nematode cysts/root system and increased ( ... | 2014 | 24600314 |
| [parasitic and lethal effects of trichoderma longibrachiatum on heterodera avenae: microscopic observation and bioassay]. | a laboratory experiment was conducted to study the parasitic and lethal effects of trichoderma longibrachiatum conidia suspension on heterodera avenae cysts. different concentrations (1.5 x 10(5)-1.5 x 10(7) cfu x ml(-1)) of t. longibrachiatum conidia suspension had strong parasitic and lethal effects on h. avenae cysts, and the effects differed significantly among the different concentrations. when treated with the t. longibrachiatum conidia suspension at a concentration of 1.5 x 10(7) cfu x ml ... | 2013 | 24483093 |
| characterization of genetic homogeneity of an indian population of cereal cyst nematode, heterodera avenae using sequencing and pcr-rflp of ribosomal dna. | the cereal cyst nematodes belonging to heterodera avenae group is a complex species consisting of 12 valid species and overlapping morphological characters make them difficult to be distinguished from one another. the non coding internal transcribed spacer sequences, its1 and its2 including 5.8s region of ribosomal dna (rdna) has been very useful for the accurate identification of the species and characterization of molecular genetic variation within the species of plant parasitic nematodes. in ... | 2013 | 23390348 |
| cloning and characterization of two neuropeptide genes from cereal cyst nematode, heterodera avanae from india. | the cereal cyst nematode, heterodera avenae (wollenweber, 1924) is one of the most important plant parasitic nematodes of cereals. it is an obligate sedentary endo parasite causing considerable crop losses in wheat, barley and oats worldwide. fmrfamide-like peptides (flps) play critical role as neurotransmitters or neuromodulators in the nervous system and proposed as one of the important targets for the plant parasitic nematode management. therefore, for the first time we have cloned and charac ... | 2012 | 22829742 |
| de novo assembly and characterization of the root transcriptome of aegilops variabilis during an interaction with the cereal cyst nematode. | aegilops variabilis no.1 is highly resistant to cereal cyst nematode (ccn). however, a lack of genomic information has restricted studies on ccn resistance genes in ae. variabilis and has limited genetic applications in wheat breeding. | 2012 | 22494814 |
| analysis of ascorbate peroxidase genes expressed in resistant and susceptible wheat lines infected by the cereal cyst nematode, heterodera avenae. | changes in ascorbate peroxidase (apx) enzyme activity in response to nematode (heterodera avenae) attack were studied in roots of three hexaploid wheat lines carrying cre2, cre5, or cre7 nematode resistance genes and the susceptible triticum aestivum cv. anza. a spectrophotometric analysis was carried out with root extracts of infected plants 4, 7, 11, and 14 days after nematode inoculation using uninfected plant as control. apx induction in infected resistant genotypes was similar and higher th ... | 2010 | 20690022 |
| analysis of class iii peroxidase genes expressed in roots of resistant and susceptible wheat lines infected by heterodera avenae. | the response of resistant wheat-aegilops ventricosa introgression line h-93-8 and its susceptible parent, triticum aestivum h-10-15, to ha71 spanish population of heterodera avenae was studied to determine the changes in peroxidase gene expression during incompatible and compatible wheat-nematode interactions. twenty peroxidase genes were characterized from both 211 expressed sequence tags and 259 genomic dna clones. alignment of deduced amino acid sequences and phylogenetic clustering with pero ... | 2009 | 19656043 |
| [characterization and expression profiling of a novel cereal cyst nematode resistance gene analog in wheat]. | based on the conserved regions of known resistance genes, a nbs-lrr type ccn resistance gene analog was isolated from the ccn resistant e-10 near isogenic lines (nils) of wheat, designated as crez (genbank acc. n: eu327996). it contained a complete orf that was 2775 bp in length and encoded 924 amino acids. sequence comparison indicated that it shared 92% nucleotide and 87% amino acid identity with those of the known ccn-resistance gene cre3 and had similar characteristic conserved motifs as tho ... | 2009 | 19140329 |
| phosphite inhibits development of the nematodes heterodera avenae and meloidogyne marylandi in cereals. | abstract phosphonic acid (h(3)po(3)) solutions were applied to wheat or to bristle oat as soil drenches before inoculation with juveniles of the sedentary, endoparasitic nematodes heterodera avenae or meloidogyne marylandi. all the solutions, which were ph adjusted and added at levels as low as 0.63 mg of phosphite (hpo(3)(2-)) per plant, reduced the numbers of h. avenae females and m. marylandi egg masses. phosphate (po(4)(3-)), applied as potassium phosphate at the same concentrations, did not ... | 2007 | 18943279 |
| biochemical and genetic studies of two heterodera avenae resistance genes transferred from aegilops ventricosa to wheat. | two heterodera avenae resistance genes, cre2 from aegilops ventricosa ap-1 and cre5 from ae. ventricosa #10, were shown to confer a high level of resistance to the spanish pathotype ha71. no susceptible plants were found in the f(2) progeny from the cross between the two accessions of ae. ventricosa, suggesting that their respective resistance factors were allelic. however, genes cre2 and cre5 apparently were transferred to a different chromosomal location in the wheat line h-93-8 and in the 6m( ... | 2003 | 12756472 |
| resistance to the cereal cyst nematode (heterodera avenae woll.) transferred from the wild grassaegilops ventricosa to hexaploid wheat by a "stepping-stone" procedure. | transfer of resistance toheterodera avenae, the cereal cyst nematode (ccn), by a "stepping-stone" procedure from the wild grassaegilops ventricosa to hexaploid wheat has been demonstrated. the number of nematodes per plant was lower, and reached a plateau much earlier, in the resistant introgression line h93-8 (1-2 nematodes per plant) than in the recipient h10-15 wheat (14-16 nematodes per plant). necrosis (hypersensitive reaction) near the nematode, little cell fusion, and few, often degraded ... | 1993 | 24190269 |
| phylogenetic relationships of a distinct species of globodera from portugal and two punctodera species. | evolutionary relationships based on ribosomal dna (rdna) sequence data for a previously unknown species of globodera from portugal, punctodera chalcoensis from mexico, and p. punctata from estonia, plus previously published sequences, support the following relationships: (((cactodera weissi, g. artemisiae, c. milleri), ((g. sp. bouro, g. sp. canha, g. sp. ladoeiro), ((g. pallida, g. rostochiensis), (p. chalcoensis, p. punctata)))), heterodera avenae). globodera sp. from portugal, which can be co ... | 2002 | 19265942 |
| a key and compendium to species of the heterodera avenae group (nematoda: heteroderidae). | a key based on cyst and juvenile characters is given for identification of 12 valid heterodera species in the h. avenae group. a compendium providing the most important diagnostic characters for use in identification of species is included as a supplement to the key. cyst characters are most useful for separating species; these include shape, color, cyst wall pattern, fenestration, vulval slit length, and the posterior cone including presence or absence of bullae and underbridge. also useful are ... | 2002 | 19265941 |
| damage and reproduction potentials of heterodera avenae on wheat under outdoor conditions. | two pot experiments, in consecutive years, were conducted under outdoor conditions during the wheat growing season to examine the relationship between increasing initial population densities (pi: 0-3,000 cysts/pot) of heterodera avenae and corresponding responses of wheat cv. yecora rojo. results of both experiments were very similar. the nematode suppressed plant height, root and biomass dry weights, and grain yield at all pi's studied. the suppression of these parameters, as well as the final ... | 1999 | 19270933 |
| are pathogenesis-related proteins induced by meloidogne javanica or heterodera avenae lnvasion? | changes in root- and leaf-soluble proteins were investigated in tomato after invasion by the root-knot nematode meloidogyne javanica, or in barley and wheat after invasion by the cereal cyst nematode heterodera avenae. infection of susceptible tomato plants by m. javanica did not cause any change in the soluble-protein composition of leaves or roots compared with uninoculated plants at an early infection stage. no pathogenesis-related proteins (chitinase, glucanase, or p-14) were induced in the ... | 1997 | 19274187 |
| an immunoreactive protein to wheat-germ agglutinin antibody is induced in oat roots following invasion of the cereal cyst nematode heterodera avenae, and by jasmonate. | a protein that cross-reacts to a wheat-germ agglutinin antibody was induced in oat roots following the invasion of second-stage juveniles (j2) of the cereal cyst nematode heterodera avenae. this protein, designated asp45, was acid soluble, and its molecular mass was about 45 kda on a sodium dodecyl sulfate-polyacrylamide gel. asp45 was induced in both compatible and incompatible interactions between the nematode and the plant, and also in roots by exposure to jasmonic acid (ja) or methyl jasmona ... | 1997 | 9353943 |
| map-based cloning of a gene sequence encoding a nucleotide-binding domain and a leucine-rich region at the cre3 nematode resistance locus of wheat. | the cre3 gene confers a high level of resistance to the root endoparasitic nematode heterodera avenae in wheat. a dna marker cosegregating with h. avenae resistance was used as an entry point for map-based cloning of a disease resistance gene family at the cre3 locus. two related gene sequences have been analysed at the cre3 locus. one, identified as a cdna clone, encodes a polypeptide with a nucleotide binding site (nbs) and a leucine-rich region; this member of the disease resistance gene fami ... | 1997 | 9352645 |
| genetic diversity among a complex of cereal cyst nematodes inferred from rflp analysis of the ribosomal internal transcribed spacer region. | this study examined the restriction polymorphism (rflp) of the nuclear ribosomal dna in heterodera avenae, h. filipjevi, h. mani, h. latipons, and the taxonomically unclear gotland strain in order to establish a molecular characterization and phylogenetic relationships in the complex of cereal cyst nematodes (ccn). the internal transcribed spacer (its) and 5.8s rdna were amplified by pcr from a single female or a cyst of 27 different geographic isolates of the ccn complex and one population of h ... | 1997 | 9276936 |
| development of a pcr-based allele-specific assay from an rflp probe linked to resistance to cereal cyst nematode in wheat. | the rflp locus xglk605 identified by the probe tag605 maps to a proximal position on the long arm of wheat chromosome 2b about 7 cm away from a gene conditioning resistance to cereal cyst nematode in the wheat line aus10894. the clone tag605 was partially sequenced and the pcr primer set awp1 was designed. the 292-bp product, which showed no polymorphism between varieties, was cloned and sequenced. a single base difference was found in the sequence of the awp1 products amplified and cloned from ... | 1996 | 8776870 |
| genetic variation in natural populations of the cereal cyst nematode (heterodera avenae woll.) submitted to resistant and susceptible cultivars of cereals. | the purpose of the present work was to study the genetic characteristics of cereal cyst nematode (heterodera avenae) populations re-established after the long-term use of resistant oat cultivars in field conditions. population features were analyzed through fitness components and variation in enzymatic polymorphism (esterase and malate dehydrogenase loci). the longest (6 year) use of the same resistance genes (oat cv panema) at high frequency (rotation ib) led to the selection of a resistance-br ... | 1996 | 24162191 |
| gold-conjugated reagents for the labeling of carbohydrate-recognition domains and glycoconjugates on nematode surfaces. | various fluorescent conjugated lectins have been used for the detection of glycoconjugates on nematode surfaces under light microscopy. several problems have been experienced with these reagents including penetration of the cuticle by fluorescent lectins, non-glycoconjugate specificity, strong nematode autofluorescence at the emission wavelength of the fluorescent dye, and prevention of persistent visualization due to rapid quenching of the fluorescent components. gold-conjugated reagents combin ... | 1996 | 19277354 |
| analysis of heterodera avenae populations by the random amplified polymorphic dna technique. | eleven populations of the heterodera avenae complex (four spanish, two british, two french, and three swedish) were studied by random amplified polymorphic dna analysis. from 5 to 11 fragments were obtained with each of 14 random primers, with fragment size ranging from 200 to 2200 bp. cluster analysis of the 11 populations, using 108 scorable markers, separate these populations into two main groups. these groups coincide with what is known as the "true" h. avenae and the "gotland strain" or "br ... | 1996 | 8851801 |
| identification of rflp markers linked to the cereal cyst nematode resistance gene (cre) in wheat. | the cereal cyst nematode (ccn) (heterodera avenae woll.) is an economically damaging pest of wheat in many of the worlds cereal growing areas. the development of ccn-resistant cultivars may be accelerated by the use of molecular markers. the cre gene of the wheat line "aus 10894" confers resistance to ccn. using a pair of near-isogenic lines (nils) that should differ only in a small chromosome segment containing the cre locus, we screened 58 group-2 probes and found two (tag605 and cdo588) that ... | 1994 | 24178105 |
| interactions between heterodera avenae and pratylenchus neglectus on wheat. | in a long-term field experiment, differential population densities of heterodera avenae were produced by frequent cropping with resistant (cv. panema) or susceptible (cv. peniarth) oat. the two oat cultivars were equally good hosts of pratylenchus neglectus in a glass house experiment with field soil. on wheat crops grown after oats in field experiments, p. neglectus population densities in roots were higher in plots where h. avenae had been controlled than in plots with moderate infestations (4 ... | 1994 | 19279901 |
| assignment of aegilops variabilis eig chromosomes and translocations carrying resistance to nematodes in wheat. | the allotetraploid species aegilops variabilis eig (2n = 28, uusvsv) belongs to the tribe triticeae and is closely related to wheat. one accession, ae. variabilis no. 1, was found to be resistant to the cereal cyst nematode (ccn) and the root-knot nematode (rkn). as the genetic variability for resistance to those two pests is limited within wheat, this accession was crossed to bread wheat. previous work enabled the development of two addition lines and two translocation lines carrying resistance ... | 2009 | 19370089 |
| the identification of candidate genes associated with pch2 eyespot resistance in wheat using cdna-aflp. | eyespot is a fungal disease of the stem base of cereal crops and causes lodging and the premature ripening of grain. wheat cultivar cappelle desprez contains a highly durable eyespot resistance gene, pch2 on the long arm of chromosome 7a. a cdna-amplified fragment length polymorphism (aflp) platform was used to identify genes differentially expressed between the eyespot susceptible variety chinese spring (cs) and the cs chromosome substitution line cappelle desprez 7a (cs/cd7a) which contains pc ... | 2009 | 19183860 |
| comparisons of isolates of heterodera avenae using 2-d page protein patterns and ribosomal dna. | six geographic isolates of heterodera avenae, including two isolates each from sweden, australia, and the united states, were compared on the basis of 2-d page protein patterns and the complete dna sequence for the two internal transcribed ribosomal dna spacers (rdna its1 and its2) and the 5.8s rrna gene. the protein pattern data and rdna its sequence data both indicated that the swedish gotland strain of h. avenae differed markedly from the rest of the isolates. protein patterns for the austral ... | 1994 | 19279877 |
| a directed search for dna sequences tightly linked to cereal cyst nematode resistance genes in triticum tauschii. | an improved system for identifying dna sequences linked to a targeted region was developed by fractionating dna sequences prior to polymerase chain reaction (pcr) analysis. in an attempt to identify dna markers linked to a strong ccn resistance gene, ccn-d1, in triticum tauschii, dna samples from individuals homozygous for resistance and susceptibility at the ccn-d1 locus in a segregating progeny were bulked separately to produce "near isogenic" dna pools. the polymerase chain reaction was emplo ... | 1994 | 18470078 |
| management of cereal cyst nematodes, heterodera spp., in norway. | cereal cyst nematodes, heterodera spp., are known worldwide as parasites of cereals and grasses. surveys of cereal fields in norway have revealed that nematodes belonging to the h. avenae complex occur throughout the country, and that h. avenae (the oat cyst nematode) is the most common species, followed by h. filipjevi (the rye cyst nematode). both species are of economic importance in scandinavia. h. avenae has been found in two common pathotypes, ha 11 and ha 12. work in sweden, however, has ... | 2006 | 17390804 |
| mapping of a novel qtl for resistance to cereal cyst nematode in wheat. | cereal cyst nematode (ccn; heterodera avenae woll.) is a root pathogen of cereals that can cause severe yield losses in intolerant wheat cultivars. loci for resistance to ccn, measured by a seedling bioassay, were identified by creating a genetic map based on a trident/molineux doubled haploid population of 182 lines. a novel locus accounting for up to 14% of the resistance to ccn was mapped to chromosome 1b of molineux by association with microsatellite marker loci xwmc719 and xgwm140. this loc ... | 2006 | 16538511 |
| plant-parasitic nematodes associated with reduced wheat yield in oregon: heterodera avenae. | heterodera avenae is widely distributed in the western united states, where most wheat is grown in non-irrigated winter wheat/summer fallow rotations in low rainfall regions. economic and social pressures have motivated growers to pursue a transition from winter wheat/summer fallow rotation to no-till annual spring cereals. annual cereals are also planted in some irrigated fields. the impact of h. avenae on spring wheat yield in the pacific northwest had been observed but not quantified. spring ... | 2005 | 19262877 |
| impact of cre1, cre8 and cre3 genes on cereal cyst nematode resistance in wheat. | the cereal cyst nematode (ccn; heterodera avenae), a root disease of cereal crops, is a major economic constraint in many wheat (triticum aestivum)-growing areas of the world. the objective of this study was to assess the impact of the cre1, cre8 and cre3 genes on ccn resistance. a population of 92 doubled-haploid (dh) lines derived from a cross between wheat cvs. frame and silverstar as well as 1,851 wheat breeding lines were screened for ccn resistance at the primary industries research victor ... | 2005 | 15655664 |
| phytoecdysteroids: a novel defense against plant-parasitic nematodes. | the phytoecdysteroid, 20-hydroxyecdysone (20e), is a major molting hormone of invertebrates, possibly including nematodes. as 20e is inducible in spinach, the defensive role against plant-parasitic nematodes was investigated. the effects of direct application on nematodes was assessed by treating cereal cyst nematode, heterodera avenae, juveniles with concentrations of 20e from 8.2 x 10(-8) to 5.2 x 10(-5) m before applying to triticum aestivum growing in sand. h. avenae, heterodera schachtii (s ... | 2004 | 15609826 |
| root enzyme activities associated with resistance to heterodera avenae conferred by gene cre7 in a wheat/aegilops triuncialis introgression line. | the effect of cereal cyst nematode (heterodera avenae) infection on the expression of putative root defence-related enzymes, peroxidase (per), esterase (est) and superoxide dismutase (sod), was studied in roots of a wheat/aegilops triuncialis introgression line tr-3531 carrying the cre7 resistance gene. we analysed detoxificant isozyme changes within roots of the resistant line and their susceptible parent (h-10-15) as a control, during the early interaction with the pathotype ha71 of h. avenae. ... | 2004 | 15128038 |
| the cre1 and cre3 nematode resistance genes are located at homeologous loci in the wheat genome. | differential responses in host-nematode pathotype interactions occur in wheat lines carrying different cereal cyst nematode resistance (cre) genes. cre1, located on chromosome 2b, confers resistance to most european nematodes and the sole australian pathotype, while cre3, present on chromosome 2d, is highly resistant to the australian pathotype and susceptible to a number of european pathotypes. genes encoding nucleotide binding site-leucine rich repeat (nbs-lrr) proteins that cosegregate with t ... | 2003 | 14651346 |
| partial resistance to heterodera avenae in wheat lines with the 6m v chromosome from aegilops ventricosa. | lines of wheat with the 6m(v) chromosome from aegilops ventricosa display partial resistance to both pathotypes hal2 and ha41 of heterodera avenae. with either pathotype, the effect of this alien chromosome on cyst production, size, and fecundity was expressed in resistance tests. partial resistance of five 6m(v)(6d) substitution lines varied according to the intrinsic cyst-forming capacity of the nematode pathotypes and the recipient germplasms. such partial resistance can be utilized in wheat ... | 1993 | 19279767 |
| abscisic acid and ethylene increase in heterodera avenae-infected tolerant or intolerant oat cultivars. | the relationship between root stunting caused by the cereal cyst nematode and levels of two root growth inhibiting hormones, abscisic acid and ethylene, was investigated in aseptically cultured root segments and in intact roots of two oat cultivars differing in tolerance to the nematode. cultured root segments of oat cultivars new zealand cape (tolerant) and sual (intolerant) were inoculated with sterilized heterodera avenae second-stage juveniles. suppressed growth of root axes and emerged late ... | 1991 | 19283149 |
| resistance toheterodera avenue in the rye genome of triticale. | the cereal cyst nematode,heterodera avenue wollenweber, is a serious pest of cereals in many countries. a high level of resistance to the unique australian pathotype of the nematode has been demonstrated in a triticale line (t701-4-6), which was originally obtained from cimmyt. the level of resistance is similar to that in rye cultivar, south australian, but higher than that in the wheat line (aus 10894), hitherto reported to have useful resistance to the australian pathotype. the gene for resis ... | 1990 | 24226350 |
| use of chitin for controlling heterodera avenae and tylenchulus semipenetrans. | the nematicidal effect of chitin, relative to other pesticides, was evaluated against two plant-parasitic nematodes, heterodera avenae and tylenchulus semipenetrans. wheat seedlings, grown in soils artificially or naturally infested with h. avenae, were treated with 0.4% (w/w) clandosan (cla) prepared from crustacean chitin, aldicarb (temik 15g), or ethylene dibromide (edb 90ec). the cla treatment significantly increased wheat straw, ear, and average grain dry weights of nematode-infected plants ... | 1989 | 19287630 |
| cereal cyst nematode (heterodera avenae) on oats. ii. early root development and nematode tolerance. | the effect of heterodera avenae infestation on early seminal and lateral root growth was examined in four oat genotypes differing in tolerance to h. avenae. recently emerged seminal roots were inoculated with a range of h. avenae larval densities, then transferred a hydroponic system to remove the effect of later nematode penetration on root development. intolerance to h. avenae was assessed in terms of impairment of seminal root extension resulting in fewer primary lateral roots emerging from t ... | 1989 | 19287624 |
| ecology and control of cereal cyst nematode (heterodera avenae) in southern australia. | the ecology and control of cereal cyst nematode in southern australia is reviewed. the wide distribution of heterodera avenae in victoria and south australia is due largely to movement of cysts by wind during dust storms. the fungus rhizoctonia solani frequently is associated with the nematode in a disease complex in wheat, and disease symptoms are most severe on lighter or well structured soils. crop rotations which include periods of fallow, or of nonhost crop reduce population levels of h. av ... | 1984 | 19294014 |
| biocontrol: fungal parasites of female cyst nematodes. | three species of fungi, catenaria auxiliarls (kühn) tribe, nematophthora gynophila kerry and crump, and a lagenidiaceous fungus have been found attacking female cyst nematodes. all are zoosporic fungi which parasitize females on the root surface, cause the breakdown of the nematode cuticle, and prevent cyst formation. their identification and some aspects of their biology are reviewed. n. gynophila is widespread in britain and reduces populations of the cereal cyst nematode, heterodera avenae wo ... | 1980 | 19300700 |