secretory granule proteins from the subventral esophageal glands of the potato cyst nematode identified by monoclonal antibodies to a protein fraction from second-stage juveniles.sodium dodecyl sulfate-extracted proteins from second-stage juveniles (j2) of the potato cyst nematode globodera rostochiensis were fractionated by preparative continuous flow electrophoresis, and monoclonal antibodies (mabs) were raised against the 38- to 40.5-kda protein fraction. screening of the hybridoma culture fluids by immunofluorescence microscopy of j2 resulted in the identification of 12 mabs that bound specifically to the subventral esophageal glands. on western blots of j2 these mab ...19968589421
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 ...19957895833
laboratory trials to infect insects and nematodes by some acaropathogenic hirsutella strains (mycota: clavicipitaceous anamorphs).laboratory assays have been carried out to artificially infect insect larvae of the birch bark-beetle (scolytus ratzeburgi jans.-coleoptera, scolytidae) and codling moth cydia pomonella l. -lepidoptera, tortricidae) as well as the potato cyst nematode-globodera rostochiensis wollenweber, sugar beet nematode-heterodera schachtii schmidt and root-knot nematode-meloidogyne hapla chif (nematoda, heteroderidae), by the phialoconidia of some fungal species of the genus hirsutella. from among four spec ...200817920621
soybean fgam synthase promoters direct ectopic nematode feeding site activity.soybean cyst nematode (scn) resistance in soybean is a complex oligogenic trait. one of the most important nematode resistance genes, rhg1, has been mapped to a distal region of molecular linkage group g in soybean. a simplified genetic system to identify soybean genes with modified expression in response to scn led to the identification of several genes within the nematode feeding sites. the genes were mapped to reveal their linkage relationship to known qtls associated with soybean cyst nemato ...200415060594
expression of an arabidopsis phosphoglycerate mutase homologue is localized to apical meristems, regulated by hormones, and induced by sedentary plant-parasitic nematodes.we previously isolated a partial soybean cdna clone whose transcript abundance is increased upon infection by the sedentary, endoparasitic soybean cyst nematode heterodera glycines. we now isolated the corresponding full-length cdna and determined that the predicted gene product was similar to the group of cofactor-dependent phosphoglycerate mutase/bisphosphoglycerate mutase enzymes (pgm/bpgm; ec we designated the corresponding soybean gene gmpgm. pgm and bpgm are key catalysts ...200315010616
population genetic structure of the sugar beet cyst nematode heterodera schachtii: a gonochoristic and amphimictic species with highly inbred but weakly differentiated populations.the sugar beet cyst nematode heterodera schachtii is a soil-dwelling phytoparasitic nematode that feeds on beet roots. it is an important pest in most sugar beet growing areas, and better knowledge of its genetic variability is an important step to preserve the durability of resistant sugar beet varieties. the population genetic structure of this species in northern france was studied using five microsatellite markers. a hierarchical sampling design was used to investigate spatial structuring at ...200414653786
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 ...200212828513
sporamin-mediated resistance to beet cyst nematodes (heterodera schachtii schm.) is dependent on trypsin inhibitory activity in sugar beet (beta vulgaris l.) hairy roots.sporamin, a sweet potato tuberous storage protein, is a kunitz-type trypsin inhibitor. its capability of conferring insect-resistance on transgenic tobacco and cauliflower has been confirmed. to test its potential as an anti-feedant for the beet cyst nematode (heterodera schachtii schm.), the sporamin gene spti-1 was introduced into sugar beet (beta vulgaris l.) by agrobacterium rhizogenes-mediated transformation. twelve different hairy root clones expressing sporamin were selected for studying ...200312777044
bacterial rrna genes associated with soil suppressiveness against the plant-parasitic nematode heterodera schachtii.the goal of this study was to identify bacteria involved in soil suppressiveness against the plant-parasitic nematode heterodera schachtii. since h. schachtii cysts isolated from the suppressive soil can transfer this beneficial property to nonsuppressive soils, analysis of the cyst-associated microorganisms should lead to the identification of the causal organisms. our experimental approach was to identify bacterial rrna genes (rdna) associated with h. schachtii cysts obtained from soil mixture ...200312620845
arabidopsis gene expression changes during cyst nematode parasitism revealed by statistical analyses of microarray expression profiles.with the availability of microarray technology, the expression profiles of thousands of genes can be monitored simultaneously to help determine the mechanisms of these biological processes. we conducted affymetrix genechip microarray analyses of the arabidopsis-cyst nematode interaction and employed a statistical procedure to analyze the resultant data, which allowed us to identify significant gene expression changes. quantitative real-time rt-pcr assays were used to confirm the microarray analy ...200312609032
analysis of nematode-responsive promoters in sugar beet hairy of the strategies to make crops resistant to the beet cyst nematode heterodera schachtii is the destruction of the feeding site or syncytium. this can be achieved by local expression of the cytotoxic barnase gene under control of a nematode-inducible plant promoter that is active in the syncytium. expression of barnase outside the feeding site has to be neutralized by its inhibitor barstar driven from a constitutive promoter that is downregulated in the syncytium. several promoters that are ...200112425082
promoter analysis of pyk20, a gene from arabidopsis thaliana.the gene pyk20 which has been isolated from arabidopsis thaliana encodes a protein with a glutamine-rich domain in the c-terminal region. the transcription of this gene was shown to be induced in feeding sites of root-parasitic nematodes (heterodera schachtii), in roots infected by a fungus-like organism (plasmodiophora brassicae), by plant hormone treatment, and by wounding. in order to identify functional promoter regions seven different 5' and 3' pyk20 promoter (ppyk20) deletion fragments wer ...200010960738
detection of alien chromatin conferring resistance to the beet cyst nematode (heterodera schachtii schm.) in cultivated beet (beta vulgaris l.) using in situ hybridization.chromatin originating from wild beets of the genus beta, section procumbentes, has been investigated in nematode-resistant hybrid-derived lines of sugar beet (beta vulgaris l.) by in situ hybridization using satellite, telomeric and ribosomal dna repeats, a yeast artificial chromosome (yac) and total genomic dna as probes. the allen chromosome was detected in three monosomic addition lines (2n = 18 + 1) by genomic in situ hybridization. fluorescence in situ hybridization with a genome-specific s ...19979246412
antioxidant enzymes in phytoparasitic nematodes.presence of different antioxidant enzymes, such as superoxide dismutase (sod), catalase, and ascorbate, p-phenilendiamine-pyrocathecol (ppd-pc), o-dianisidine, and guaiacol isoperoxidases, was shown in the phytoparasific nematode species meloidogyne incognita, m. hapla, globodera rostochiensis, g. pallida, heterodera schachtii, h. carotae, and xiphinema index. the activity of the enzymes tested differed among the life stages examined. sod was present in cysts but was not detected in meloidogyne ...199719274144
survey of crop losses in response to phytoparasitic nematodes in the united states for 1994.previous reports of crop losses to plant-parasitic nematodes have relied on published results of survey data based on certain commodities, including tobacco, peanuts, cotton, and soybean. reports on crop-loss assessment by land-grant universities and many commodity groups generally are no longer available, with the exception of the university of georgia, the beltwide cotton conference, and selected groups concerned with soybean. the society of nematologists extension committee contacted extensio ...199919270925
evaluation of biocontrol activity of rhizobacteria from beta vulgaris against heterodera hundred fifty rhizobacteria isolated from roots of swiss chard grown in a soil suppressive to the sugar beet cyst nematode, heterodera schachtii, were tested for their influence on the nematode's ability to hatch and infect roots. two screening systems were used that focused on the ability of bacteria to inhibit either nematode hatching or root infection. most of the bacterial strains reduced hatching in vitro compared to the control, while with 5% of the strains there were 0% hatch. seven p ...199919270875
phenotypic and molecular analysis of a pasteuria strain parasitic to the sting nematode.pasteuria strain s-1 was found to parasitize the sting nematode belonolaimus longicaudatus. s-1 spores attached to several strains of b. longicaudatus from different geographical locations within the united states. however, they did not adhere to any of the following species: heterodera schachtii, longidorus africanus, meloidogyne hapla, m. incognita, m. javanica, pratylenchus brachyurus, p. scribneri, p. neglectus, p. penetrans, p. thornei, p. vulnus, and xiphinema spp. the 16s rrna genes from ...200119266005
characterization of root-knot nematode resistance in medicago truncatula.root knot (meloidogyne spp.) and cyst (heterodera and globodera spp.) nematodes infect all important crop species, and the annual economic loss due to these pathogens exceeds $90 billion. we screened the worldwide accession collection with the root-knot nematodes meloidogyne incognita, m. arenaria and m. hapla, soybean cyst nematode (scn-heterodera glycines), sugar beet cyst nematode (sbcn-heterodera schachtii) and clover cyst nematode (clcn-heterodera trifolii), revealing resistant and suscepti ...200819259519
influence of lysobacter enzymogenes strain c3 on nematodes.chitinolytic microflora may contribute to biological control of plant-parasitic nematodes by causing decreased egg viability through degradation of egg shells. here, the influence of lysobacter enzymogenes strain c3 on caenorhabditis elegans, heterodera schachtii, meloidogyne javanica, pratylenchus penetrans, and aphelenchoides fragariae is described. exposure of c. elegans to l. enzymogenes strain c3 on agar resulted in almost complete elimination of egg production and death of 94% of hatched j ...200619259452
cellulose binding protein from the parasitic nematode heterodera schachtii interacts with arabidopsis pectin methylesterase: cooperative cell wall modification during parasitism.plant-parasitic cyst nematodes secrete a complex of cell wall-digesting enzymes, which aid in root penetration and migration. the soybean cyst nematode heterodera glycines also produces a cellulose binding protein (hg cbp) secretory protein. to determine the function of cbp, an orthologous cdna clone (hs cbp) was isolated from the sugar beet cyst nematode heterodera schachtii, which is able to infect arabidopsis thaliana. cbp is expressed only in the early phases of feeding cell formation and no ...200819001564
suppression of the plant-parasitic nematode heterodera schachtii by the fungus dactylella oviparasitica.this study examined the role of the fungi dactylella oviparasitica and fusarium oxysporum in the beet-cyst nematode (heterodera schachtii) suppressiveness exhibited by a southern californian soil. in prior research, the abundance of d. oviparasitica rrna genes positively correlated with high levels of suppressiveness, whereas the abundance of f. oxysporum rrna genes positively correlated with minimal to moderate levels of suppressiveness. in this report, both fungi were added to fumigation-induc ...200618944211
identification of fungal rdna associated with soil suppressiveness against heterodera schachtii using oligonucleotide fingerprinting.abstract to understand the nature of a soil with suppressiveness against heterodera schachtii, an rdna analysis was used to identify fungi associated with h. schachtii cysts obtained from soils possessing various levels of suppressiveness. because h. schachtii cysts isolated from these suppressive soils can transfer this beneficial property to nonsuppressive soils, analysis of the microorganisms associated with the cysts should lead to the identification of the causal organisms. five soil treatm ...200318943867
induction of beet-cyst nematode suppressiveness by the fungi dactylella oviparasitica and fusarium oxysporum in field microplots.abstract the ability of dactylella oviparasitica and fusarium oxysporum to suppress heterodera schachtii numbers was examined in field microplots. fungi were individually added to fumigated field soil that was seeded with sugar beet. four weeks later, soils were infested with h. schachtii second-stage juveniles (j2). at two harvests, 11 weeks and 19 weeks (1,469 and 2,547 degree days (base 8 degrees c), respectively) after nematode-infestation, h. schachtii cyst and egg numbers were assessed. at ...200618943750
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 ...199319279850
delivery of macromolecules to plant parasitic nematodes using a tobacco rattle virus vector.plant parasitic nematodes cause significant damage to crops on a worldwide scale. these nematodes are often soil dwelling but rely on plants for food and to sustain them during reproduction. complex interactions occur between plants and nematodes during the nematode life cycle with plant roots developing specialized feeding structures through which nematodes withdraw nutrients. here we describe a novel method for delivering macromolecules to feeding nematodes using a virus-based vector [tobacco ...200717764517
a new class of ubiquitin extension proteins secreted by the dorsal pharyngeal gland in plant parasitic cyst performing cdna aflp on pre- and early parasitic juveniles, we identified genes encoding a novel type of ubiquitin extension proteins secreted by the dorsal pharyngeal gland in the cyst nematode heterodera schachtii. the proteins consist of three domains, a signal peptide for secretion, a mono-ubiquitin domain, and a short c-terminal positively charged domain. a gfp-fusion of this protein is targeted to the nucleolus in tobacco by-2 cells. we hypothesize that the c-terminal peptide might have ...200415305605
monoclonal antibodies to the esophageal glands and stylet secretions of heterodera glycines.three monodonal antibodies (mabs) that bound to secretory granules within the subventral esophageal glands of second-stage juveniles (j2) of the soybean cyst nematode (scn), heterodera glycines, were developed from intrasplenic immunizations of a mouse with homogenates of scn j2. two mabs to the secretory granules within subventral glands and one mab to granules within the dorsal esophageal gland of scn j2 were developed by intrasplenic immunizations with j2 stylet secretions. stylet secretions, ...199419279890
raphanus sativus, sinapis alba, and fagopyrum esculentum as hosts to meloidogyne incognita, meloidogyne javanica, and plasmodiophora brassicae.cultivars of oilseed radish (raphanus sativus var. oleifera cv. adagio, nemex, pegletta, renova, siletina, siletta nova, and ultimo), white mustard (sinapis alba cv. albatross, emergo, maxi, martigena, metex, and serval), buckwheat (fagopyrum esculentum cv. prego, tardo), and phacelia (phacelia tanacetifolia cv. angelia) were tested for susceptibility to meloidogyne incognita race 3 and meloidogyne javanica. experiments were conducted in growth chambers at 25 c and 16 hours light for 42 days aft ...199419279960
random amplified polymorphic dna analysis of heterodera cruciferae and h. schachtii populations.heterodera schachtii and h. cruciferae are sympatric in california and frequently occur in the same field upon the same host. we have investigated the use of polymerase chain reaction (pcr) amplification of nematode dna sequences to differentiate h. schachtii and h. cruciferae and to assess genetic variability within each species. single, random oligodeoxyribonucleotide primers were used to generate pcr-amplified fragments, termed rapd (random amplified polymorphic dna) markers, from genomic dna ...199219283007
management of plant-parasitic nematodes with a chitin-urea soil amendment and other materials.field trials were conducted with a chitin-urea soil amendment and several other nematicides on four crop-nematode combinations: tomato-meloidogyne incognita; potato-meloidogyne chitwoodi; walnut-pratylenchus vulnus; and brussels sprouts-heterodera schachtii. significant (p </= 0.10) nematode population reductions were obtained with the chitin-urea soil amendment in the trims on potato and walnut. in the trials on brussels sprouts and on tomato, phytotoxicity occurred at rates of 1,868 and 1,093 ...199219283044
extraction of cyst nematodes from organic soils.the effects of extraction technique, sample size, soil moisture level, and overflow rate on recovery of globodera rostochiensis and (or) heterodera schachtii cysts from organic soils were investigated. a modified fenwick can (mfc) and an underflow elutriator (ue) described in this paper were evaluated and compared for cyst recovery efficiency and amount of organic flotsam collected. the mfc and ue extracted similar numbers of cysts, but the ue collected 50% less flotsam than the mfc. sample size ...198719290113
altered sucrose synthase and invertase expression affects the local and systemic sugar metabolism of nematode-infected arabidopsis thaliana plants.sedentary endoparasitic nematodes of plants induce highly specific feeding cells in the root central cylinder. from these, the obligate parasites withdraw all required nutrients. the feeding cells were described as sink tissues in the plant's circulation system that are supplied with phloem-derived solutes such as sugars. currently, there are several publications describing mechanisms of sugar import into the feeding cells. however, sugar processing has not been studied so far. thus, in the pres ...201324187419
comparative electrophoretic analyses of soluble proteins from heterodera glycines races 1-4 and three other heterodera species.modified polyacrylamide gel and sds-polyacrylamide gel electrophoretic systems using a low molarity tris-hcl buffer and equal ph of homogenizing buffer and stacking gel provided improved stacking for separation of soluble proteins from heterodera schachtii, h. trifolii, h. lespedezae, and h. glycines races 1, 2, 3, and 4, compared with previous studies with cyst nematodes, the four heterodera species were easily distinguished using the polyacrylamide gel system, but h. trifolii and h. lespedezae ...198419294032
differential gene expression in nematode-induced feeding structures of transgenic plants harbouring promoter-gusa fusion constructs.sedentary plant-parasitic nematodes are able to induce specialized feeding structures in the root system of their host plants by triggering a series of dramatic cellular responses. these changes presumably are accompanied by a reprogramming of gene expression. to monitor such changes, a variety of promoter-gusa fusion constructs were introduced into arabidopsis and tobacco. transgenic plants were analysed histochemically for gus activity in the nematode feeding structures after infection with ei ...19938275103
identification of cyst nematodes of agronomic and regulatory concern with pcr-rflp of its1.the first internally transcribed spacer region (its1) from cyst nematode species (heteroderidae) was compared by nucleotide sequencing and pcr-rflp. european, asian, and north american isolates of five heterodefid species were examined to assess intraspecific variation. pcr-rflp patterns of amplified its1 dna from pea cyst nematode, heterodera goettingiana, from northern ireland were identical with patterns from washington state. sequencing demonstrated that its1 heterogeneity existed within ind ...199719274157
arabidopsis spermidine synthase is targeted by an effector protein of the cyst nematode heterodera schachtii.cyst nematodes are sedentary plant parasites that cause dramatic cellular changes in the plant root to form feeding cells, so-called syncytia. 10a06 is a cyst nematode secretory protein that is most likely secreted as an effector into the developing syncytia during early plant parasitism. a homolog of the uncharacterized soybean cyst nematode (heterodera glycines), 10a06 gene was cloned from the sugar beet cyst nematode (heterodera schachtii), which is able to infect arabidopsis (arabidopsis tha ...201019965964
expression of bvglp-1 encoding a germin-like protein from sugar beet in arabidopsis thaliana leads to resistance against phytopathogenic fungi.nematode (heterodera schachtii) resistance in sugar beet (beta vulgaris) is controlled by a single dominant resistance gene, hs1(pro-1). bvglp-1 was cloned from resistant sugar beet. the bvglp-1 messenger (m)rna is highly upregulated in the resistant plants after nematode infection, suggesting its role in the hs1(pro-1) mediated resistance. bvglp-1 exhibits sequence homology to a set of plant germin-like proteins (glp), from which several have proved to be functional in plant basal or defense re ...201020192832
the promoter of the arabidopsis thaliana cel1 endo-1,4-beta glucanase gene is differentially expressed in plant feeding cells induced by root-knot and cyst nematodes.summary transgenic tobacco and arabidopsis thaliana carrying the arabidopsis endo-1,4-beta-glucanase (ec cel1 promoter fused to the beta-glucuronidase (gus) reporter gene were infected with the root-knot nematode, meloidogyne incognita, and either the tobacco cyst nematode, globodera tabacum (tobacco), or beet cyst nematode, heterodera schachtii (arabidopsis). cel1-driven gus expression was detected in cell elongation zones of noninfected plants and within feeding sites (giant-cells) in ...200420565607
nematodes as vectors to introduce agrobacterium into plant roots.summary a fast plant promoter test was developed by means of a nematode to transfer agrobacterium tumefaciens into plant roots. two-week-old arabidopsis thaliana (l.) heynh. plants were transferred to infection medium. meloidogyne incognita or heterodera schachtii juveniles were mixed with the agrobacterium strain that harboured the binary vector, and this mixture was used for plant inoculation. during migration of the nematode and establishment of the feeding site inside the roots, the t-dna wa ...200020572986
preparation and sequencing of secreted proteins from the pharyngeal glands of the plant parasitic nematode heterodera schachtii.summary in order to gain insight into the biology of the parasitic relationship between heterodera schachtii and its host plant, it is important to understand the functional role of the nematode's pharyngeal secretions. these secretions presumably play a key role in establishing and maintaining a feeding site for the nematode. an optimized method was used for the in vitro production of h. schachtii pharyngeal gland secretions. these pharyngeal secretions were mainly produced in an insoluble form ...200120573018
the novel cyst nematode effector protein 19c07 interacts with the arabidopsis auxin influx transporter lax3 to control feeding site development.plant-parasitic cyst nematodes penetrate plant roots and transform cells near the vasculature into specialized feeding sites called syncytia. syncytia form by incorporating neighboring cells into a single fused cell by cell wall dissolution. this process is initiated via injection of esophageal gland cell effector proteins from the nematode stylet into the host cell. once inside the cell, these proteins may interact with host proteins that regulate the phytohormone auxin, as cellular concentrati ...201021156858
the promoter of a plant defensin gene directs specific expression in nematode-induced syncytia in arabidopsis roots.the beet cyst nematode heterodera schachtii induces a feeding site, called syncytium, in roots of host plants. in arabidopsis, one of the genes whose expression is strongly induced in these structures is pdf2.1 which codes for an antimicrobial plant defensin. arabidopsis has 13 plant defensin genes. besides pdf2.1, the pdf2.2 and pdf2.3 genes were strongly expressed in syncytia and therefore the expression of all three pdf genes was studied in detail. the promoter of the pdf2.1 gene turned out t ...201121813283
population dynamics of dactylella oviparasitica and heterodera schachtii: toward a decision model for sugar beet planting.a series of experiments were performed to examine the population dynamics of the sugarbeet cyst nematode, heterodera schachtii, and the nematophagus fungus dactylella oviparasitica. after two nematode generations, the population densities of h. schachtii were measured in relation to various initial infestation densities of both d. oviparasitica and h. schachtii. in general, higher initial population densities of d. oviparasitica were associated with lower final population densities of h. schacht ...201223481664
the cyst nematode effector protein 10a07 targets and recruits host posttranslational machinery to mediate its nuclear trafficking and to promote parasitism in arabidopsis.plant-parasitic cyst nematodes synthesize and secrete effector proteins that are essential for parasitism. one such protein is the 10a07 effector from the sugar beet cyst nematode, heterodera schachtii, which is exclusively expressed in the nematode dorsal gland cell during all nematode parasitic stages. overexpression of h. schachtii 10a07 in arabidopsis thaliana produced a hypersusceptible phenotype in response to h. schachtii infection along with developmental changes reminiscent of auxin eff ...201525715285
the transcriptome of syncytia induced by the cyst nematode heterodera schachtii in arabidopsis roots.arabidopsis thaliana is a host for the sugar beet cyst nematode heterodera schachtii. juvenile nematodes invade the roots and induce the development of a syncytium, which functions as a feeding site for the nematode. here, we report on the transcriptome of syncytia induced in the roots of arabidopsis. microaspiration was employed to harvest pure syncytium material, which was then used to prepare rna for hybridization to affymetrix genechips. initial data analysis showed that the gene expression ...200818980640
a role for atwrky23 in feeding site establishment of plant-parasitic nematodes.during the interaction between sedentary plant-parasitic nematodes and their host, complex morphological and physiological changes occur in the infected plant tissue, finally resulting in the establishment of a nematode feeding site. this cellular transformation is the result of altered plant gene expression most likely induced by proteins injected in the plant cell by the nematode. here, we report on the identification of a wrky transcription factor expressed during nematode infection. using bo ...200818599655
identification of genes involved in the response of arabidopsis to simultaneous biotic and abiotic field conditions, plants may experience numerous environmental stresses at any one time. research suggests that the plant response to multiple stresses is different from that for individual stresses, producing nonadditive effects. in particular, the molecular signaling pathways controlling biotic and abiotic stress responses may interact and antagonize one another. the transcriptome response of arabidopsis (arabidopsis thaliana) to concurrent water deficit (abiotic stress) and infection with ...201323800991
overexpression of the transcription factor rap2.6 leads to enhanced callose deposition in syncytia and enhanced resistance against the beet cyst nematode heterodera schachtii in arabidopsis roots.cyst nematodes invade the roots of their host plants as second stage juveniles and induce a syncytium which is their source of nutrients throughout their life. a transcriptome analysis of syncytia induced by the beet cyst nematode heterodera schachtii in arabidopsis roots has shown that gene expression in the syncytium is different from that of the root with thousands of genes upregulated or downregulated. among the downregulated genes are many which code for defense-related proteins. one gene w ...201323510309
apoplastic venom allergen-like proteins of cyst nematodes modulate the activation of basal plant innate immunity by cell surface receptors.despite causing considerable damage to host tissue during the onset of parasitism, nematodes establish remarkably persistent infections in both animals and plants. it is thought that an elaborate repertoire of effector proteins in nematode secretions suppresses damage-triggered immune responses of the host. however, the nature and mode of action of most immunomodulatory compounds in nematode secretions are not well understood. here, we show that venom allergen-like proteins of plant-parasitic ne ...201425500833
the beet cyst nematode heterodera schachtii modulates the expression of wrky transcription factors in syncytia to favour its development in arabidopsis roots.cyst nematodes invade the roots of their host plants as second stage juveniles and induce a syncytium which is the only source of nutrients throughout their life. a recent transcriptome analysis of syncytia induced by the beet cyst nematode heterodera schachtii in arabidopsis roots has shown that thousands of genes are up-regulated or down-regulated in syncytia as compared to root segments from uninfected plants. among the down-regulated genes are many which code for wrky transcription factors. ...201425033038
plant resistance against the parasitic nematode heterodera schachtii is mediated by mpk3 and mpk6 kinases, which are controlled by the mapk phosphatase ap2c1 in arabidopsis.plant-parasitic cyst nematodes infect plants and form highly sophisticated feeding sites in roots. it is not known which plant cell signalling mechanisms trigger plant defence during the early stages of nematode parasitism. mitogen-activated protein kinases (mapks) are central components of protein phosphorylation cascades transducing extracellular signals to plant defence responses. mapk phosphatases control kinase activities and the signalling outcome. the involvement and the role of mpk3 and ...201526438412
systemic above- and belowground cross talk: hormone-based responses triggered by heterodera schachtii and shoot herbivores in arabidopsis thaliana.above- and belowground plant parts are simultaneously attacked by different pests and pathogens. the host mediates these interactions and physiologically reacts, e.g. with local and systemic alterations of endogenous hormone levels coupled with coordinated transcriptional changes. this in turn affects attractiveness and susceptibility of the plant to subsequent attackers. here, the model plant arabidopsis thaliana is used to study stress hormone-based systemic responses triggered by simultaneous ...201526324462
development of heterodera schachtii on large rooted crop plants and the significance of root debris as substratum for increasing field infestations.heterodera schachtii developed to maturity and reproduced on the lateral roots of defoliated sugarbeet which were buried to a depth of 2.5 cm in sterilized soil and inoculated with cysts. nematodes did not develop on detached lateral roots or on roots of young defoliated beets which did not have a large tap root. the storage roots of large rooted plants were sliced, placed in small jars, inoculated with cysts, covered with moist granulated agar or soil and incubated at 24 degrees c 12-62 days. t ...197219319274
antagonistic interaction of heterodera schachtii schmidt and fusarium oxysporum (woll.) on a field experiment, nematicides controlled the disease of sugarbeets caused by heterodera schachtii and fusarium oxysporum. biocides that were both fungicidal and nematicidal also controlled the disease, but sugar yields were no higher than those obtained with the plain nematicides. in greenhouse experiments, the interaction between h. schachtii and f. oxysporam was disadvantageous to the nematode. damage to sugarbeets was less when the fungus and the nematode were present than when only the ...197019322329
a nematode effector protein similar to annexins in host plants.nematode parasitism genes encode secreted effector proteins that play a role in host infection. a homologue of the expressed hg4f01 gene of the root-parasitic soybean cyst nematode, heterodera glycines, encoding an annexin-like effector, was isolated in the related heterodera schachtii to facilitate use of arabidopsis thaliana as a model host. hs4f01 and its protein product were exclusively expressed within the dorsal oesophageal gland secretory cell in the parasitic stages of h. schachtii. hs4f ...201019887499
the arabidopsis bhlh25 and bhlh27 transcription factors contribute to susceptibility to the cyst nematode heterodera schachtii.successful cyst nematode parasitism depends on the formation and maintenance of feeding sites (syncytia) in host roots, and these processes are highly regulated by the interaction between the cyst nematode and the host. using an integrated research approach and the arabidopsis-beta vulgaris (sugar beet) cyst nematode (heterodera schachtii) pathosystem, we have determined that the two arabidopsis basic helix-loop-helix transcription factors bhlh25 and bhlh27 positively influence cyst nematode par ...201121223395
transport of the nematicide oxamyl in roots transformed with agrobacterium rhizogenes.infection of roots transformed with agrobacterium rhizogenes by meloidogyne incognita and heterodera schachtii second-stage juveniles was established in bicompartmental petri dishes. one compartment contained the murashige and skoog agar medium and the nematicide oxamyl, and the other compartment contained water agar. transformed roots of carrot, tomato, alfalfa, cowpea, rape, and sugarbeet were placed in the nutrient compartment and grew over the barrier that divided the petri dishes and into t ...198819290298
the interrelationship of heterodera schachtii and ditylenchus dipsaci on sugarbeet.heterodera schachtii significantly (p = 0.05) reduced sugarbeet root growth below that of uninoculated controls at 20, 24, and 28 c, and ditylenchus dipsaci significantly (p = 0.05) reduced root growth below that of uninoculated controls at 16, 20, 24, and 28 c. a combination of h. schachtii and d. dipsaci significantly (p = 0.05) reduced root growth below that of single inoculations of h. schachtii at all temperatures and d. dipsaci at 20, 24, and 28 c. single inoculations of h. schachtii and d ...198319295828
functional c-terminally encoded peptide (cep) plant hormone domains evolved de novo in the plant parasite rotylenchulus reniformis.sedentary plant-parasitic nematodes (ppns) induce and maintain an intimate relationship with their host, stimulating cells adjacent to root vascular tissue to re-differentiate into unique and metabolically active 'feeding sites'. the interaction between ppns and their host is mediated by nematode effectors. we describe the discovery of a large and diverse family of effector genes, encoding c-terminally encoded peptide (cep) plant hormone mimics (rrceps), in the syncytia-forming plant parasite ro ...201626996971
heterozygote deficits in cyst plant-parasitic nematodes: possible causes and consequences.deviations of genotypic frequencies from hardy-weinberg equilibrium (hwe) expectations could reveal important aspects of the biology of populations. deviations from hwe due to heterozygote deficits have been recorded for three plant-parasitic nematode species. however, it has never been determined whether the observed deficits were due (i) to the presence of null alleles, (ii) to a high level of consanguinity and/or (iii) to a wahlund effect. the aim of the present work was, while taking into th ...201525735762
exploitation of fta cartridges for the sampling, long-term storage, and dna-based analyses of plant-parasitic nematodes.the use of dna-based analyses in molecular plant nematology research has dramatically increased over recent decades. therefore, the development and adaptation of simple, robust, and cost-effective dna purification procedures are required to address these contemporary challenges. the solid-phase-based approach developed by flinders technology associates (fta) has been shown to be a powerful technology for the preparation of dna from different biological materials, including blood, saliva, plant t ...201424093923
influence of nonhosts, crucifers, and fungal parasites on field populations of heterodera schachtii.heterodera schaehtii egg number decline under nonhosts was surveyed for 3-4 years at soil depths of 0-30 cm and 30-60 cm in three fields in the imperial valley, california. in the two fields continously cropped to alfalfa, annual decline rates were 49 and 63%, respectively, and did not differ (p = 0.05) between depths. in the third field, cropped to annual nonhosts and fallowed, decline rates of 56 and 80% at 0-30-cm and 30-60-cm depths, respectively, were significantly different (p = 0.05). egg ...198119300739
analysis of the transcriptome of the infective stage of the beet cyst nematode, h. schachtii.the beet cyst nematode, heterodera schachtii, is a major root pest that significantly impacts the yield of sugar beet, brassicas and related species. there has been limited molecular characterisation of this important plant pathogen: to identify target genes for its control the transcriptome of the pre-parasitic j2 stage of h. schachtii was sequenced using roche gs flx. ninety seven percent of reads (i.e., 387,668) with an average phred score > 22 were assembled with cap3 and clc genomics workbe ...201626824923
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 ...201626858546
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 ...200415609826
soybean cyst nematode culture collections and field populations from north carolina and missouri reveal high incidences of infection by viruses.five viruses were previously discovered infecting soybean cyst nematodes (scn; heterodera glycines) from greenhouse cultures maintained in illinois. in this study, the five viruses [scnv, scpv, scrv, sctv, and sbcnv-5] were detected within scn greenhouse and field populations from north carolina (nc) and missouri (mo). the prevalence and titers of viruses in scn from 43 greenhouse cultures and 25 field populations were analyzed using qrt-pcr. viral titers within scn greenhouse cultures were simi ...201728141854
ethylene response pathway modulates attractiveness of plant roots to soybean cyst nematode heterodera glycines.plant parasitic nematodes respond to root exudates to locate their host roots. in our studies second stage juveniles of heterodera glycines, the soybean cyst nematode (scn), quickly migrated to soybean roots in pluronic f-127 gel. roots of soybean and non-host arabidopsis treated with the ethylene (et)-synthesis inhibitor aminoethoxyvinylglycine (avg) were more attractive to scn than untreated roots, and significantly more nematodes penetrated into roots. moreover, arabidopsis et insensitive mut ...201728112257
population genetics of hirsutella rhossiliensis, a dominant parasite of cyst nematode juveniles on a continental scale.hirsutella rhossiliensis is a parasite of juvenile nematodes, effective against a diversity of plant-parasitic nematodes. its global distribution on various nematode hosts and its genetic variation for several geographic regions have been reported, while the global population genetic structure and factors underlying patterns of genetic variation of h. rhossiliensis are unclear. in this study, 87 h. rhossiliensis strains from five nematode species (globodera sp., criconemella xenoplax, rotylenchu ...201627542936
sequence and spatiotemporal expression analysis of cle-motif containing genes from the reniform nematode (rotylenchulus reniformis linford & oliveira).the reniform nematode, rotylenchulus reniformis, is a sedentary semi-endoparasitic species with a host range that encompasses more than 77 plant families. nematode effector proteins containing plant-ligand motifs similar to clavata3/esr (cle) peptides have been identified in the heterodera, globodera, and meloidogyne genera of sedentary endoparasites. here, we describe the isolation, sequence analysis, and spatiotemporal expression of three r. reniformis genes encoding putative cle motifs named ...201526170479
enhanced resistance to soybean cyst nematode heterodera glycines in transgenic soybean by silencing putative cle receptors.cle peptides are small extracellular proteins important in regulating plant meristematic activity through the cle-receptor kinase-wox signalling module. stem cell pools in the sam (shoot apical meristem), ram (root apical meristem) and vascular cambium are controlled by cle signalling pathways. interestingly, plant-parasitic cyst nematodes secrete cle-like effector proteins, which act as ligand mimics of plant cle peptides and are required for successful parasitism. recently, we demonstrated tha ...201525581705
manipulation of two α-endo-β-1,4-glucanase genes, atcel6 and gmcel7, reduces susceptibility to heterodera glycines in soybean roots.plant endo-β-1,4-glucanases (egases) include cell wall-modifying enzymes that are involved in nematode-induced growth of syncytia (feeding structures) in nematode-infected roots. egases in the α- and β-subfamilies contain signal peptides and are secreted, whereas those in the γ-subfamily have a membrane-anchoring domain and are not secreted. the arabidopsis α-egase at1g48930, designated as atcel6, is known to be down-regulated by beet cyst nematode (heterodera schachtii) in arabidopsis roots, wh ...201424844661
the interaction of the novel 30c02 cyst nematode effector protein with a plant β-1,3-endoglucanase may suppress host defence to promote parasitism.phytoparasitic nematodes secrete an array of effector proteins to modify selected recipient plant cells into elaborate and essential feeding sites. the biological function of the novel 30c02 effector protein of the soybean cyst nematode, heterodera glycines, was studied using arabidopsis thaliana as host and the beet cyst nematode, heterodera schachtii, which contains a homologue of the 30c02 gene. expression of hg30c02 in arabidopsis did not affect plant growth and development but increased pla ...201222442414
altered expression of a chloroplast protein affects the outcome of virus and nematode infection.the chloroplast-resident rna helicase ise2 (increased size exclusion limit 2) can modulate the formation and distribution of plasmodesmata and intercellular trafficking. we have determined that ise2 expression is induced by viral infection. therefore the responses of nicotiana benthamiana plants with varying levels of ise2 expression to infection by tobacco mosaic virus (tmv) and turnip mosaic virus (tumv) were examined. surprisingly, increased or decreased ise2 expression led to faster viral sy ...201728323529
in vitro uptake of 140 kda bacillus thuringiensis nematicidal crystal proteins by the second stage juvenile of meloidogyne hapla.plant-parasitic nematodes (ppns) are piercing/sucking pests, which cause severe damage to crops worldwide, and are difficult to control. the cyst and root-knot nematodes (rkn) are sedentary endoparasites that develop specialized multinucleate feeding structures from the plant cells called syncytia or giant cells respectively. within these structures the nematodes produce feeding tubes, which act as molecular sieves with exclusion limits. for example, heterodera schachtii is reportedly unable to ...201222737212
protease activity and phytocystatin expression in arabidopsis thaliana upon heterodera schachtii infection.the activity of plant proteases is important for amino acids recycling, removal of damaged proteins as well as defence responses. the second-stage juvenile of the beet cyst nematode heterodera schachtii penetrates host roots and induces the feeding site called a syncytium. to determine whether infection by h. schachtii affects proteolysis, the protease activity was studied in arabidopsis roots and shoots at the day of inoculation and 3, 7 and 15 days post inoculation (dpi). nematode infection ca ...201627816823
temporal sampling helps unravel the genetic structure of naturally occurring populations of a phytoparasitic nematode. 2. separating the relative effects of gene flow and genetic drift.studying wild pathogen populations in natural ecosystems offers the opportunity to better understand the evolutionary dynamics of biotic diseases in crops and to enhance pest control strategies. we used simulations and genetic markers to investigate the spatial and temporal population genetic structure of wild populations of the beet cyst nematode heterodera schachtii on a wild host plant species, the sea beet (beta vulgaris spp. maritima), the wild ancestor of cultivated beets. our analysis of ...201627606008
arabidopsis mir827 mediates post-transcriptional gene silencing of its ubiquitin e3 ligase target gene in the syncytium of the cyst nematode heterodera schachtii to enhance susceptibility.micrornas (mirnas) are a major class of small non-coding rnas with emerging functions in biotic and abiotic interactions. here, we report on a new functional role of arabidopsis mir827 and its nitrogen limitation adaptation (nla) target gene in mediating plant susceptibility to the beet cyst nematode heterodera schachtii. cyst nematodes are sedentary endoparasites that induce the formation of multinucleated feeding structures termed syncytia in the roots of host plants. using promoter:gus fusion ...201627304416
temporal sampling helps unravel the genetic structure of naturally occurring populations of a phytoparasitic nematode. 1. insights from the estimation of effective population sizes.the sustainability of modern agriculture relies on strategies that can control the ability of pathogens to overcome chemicals or genetic resistances through natural selection. this evolutionary potential, which depends partly on effective population size (n e ), is greatly influenced by human activities. in this context, wild pathogen populations can provide valuable information for assessing the long-term risk associated with crop pests. in this study, we estimated the effective population size ...201626989440
prevalence, distribution and intraspecific variation of heterodera schachtii populations from semiarid environment.a two-year survey study was carried-out to identify and determine the distribution, community characteristics and intraspecific variation of the sugar beet cyst nematode, heterodera schachtii populations collected from the six major sugar beet-producing governorates in syria, west asia. a total of 178 composite rhizosphere soil samples were collected from the six governorates during 2009 and 2010 growing seasons as follows: aleppo (26), ar raqqah (17), dayr az zawr (33), idlib (34), hamah (41) a ...201626981013
the role of cytokinin during infection of arabidopsis thaliana by the cyst nematode heterodera schachtii.plant-parasitic cyst nematodes induce the formation of hypermetabolic feeding sites, termed syncytia, as their sole source of nutrients. the formation of the syncytium is orchestrated by the nematode, in part, by modulation of phytohormone responses, including cytokinin. in response to infection by the nematode heterodera schachtii, cytokinin signaling is transiently induced at the site of infection and in the developing syncytium. arabidopsis lines with reduced cytokinin sensitivity show reduce ...201626479273
a parasitic nematode releases cytokinin that controls cell division and orchestrates feeding site formation in host plants.sedentary plant-parasitic cyst nematodes are biotrophs that cause significant losses in agriculture. parasitism is based on modifications of host root cells that lead to the formation of a hypermetabolic feeding site (a syncytium) from which nematodes withdraw nutrients. the host cell cycle is activated in an initial cell selected by the nematode for feeding, followed by activation of neighboring cells and subsequent expansion of feeding site through fusion of hundreds of cells. it is generally ...201526417108
activity profiling reveals changes in the diversity and activity of proteins in arabidopsis roots in response to nematode infection.cyst nematodes are obligate, sedentary endoparasites with a highly specialised biology and a huge economic impact in agriculture. successful parasitism involves morphological and physiological modifications of the host cells which lead to the formation of specialised syncytial feeding structures in roots. the development of the syncytium is aided by a cocktail of nematode effectors that manipulate the host plant activities in a complex network of interactions through post-translational modificat ...201526408809
the arabidopsis immune regulator srfr1 dampens defences against herbivory by spodoptera exigua and parasitism by heterodera schachtii.plants have developed diverse mechanisms to fine tune defence responses to different types of enemy. cross-regulation between signalling pathways may allow the prioritization of one response over another. previously, we identified suppressor of rps4-rld1 (srfr1) as a negative regulator of enhanced disease susceptibility1 (eds1)-dependent effector-triggered immunity against the bacterial pathogen pseudomonas syringae pv. tomato strain dc3000 expressing avrrps4. the use of multiple stresses is a p ...201626310916
role of stress-related hormones in plant defence during early infection of the cyst nematode heterodera schachtii in arabidopsis.heterodera schachtii, a plant-parasitic cyst nematode, invades host roots and induces a specific syncytial feeding structure, from which it withdraws all required nutrients, causing severe yield losses. the system h. schachtii-arabidopsis is an excellent research model for investigating plant defence mechanisms. such responses are suppressed in well-established syncytia, whereas they are induced during early parasitism. however, the mechanisms by which the defence responses are modulated and the ...201525825039
local and systemic transcriptional responses to crosstalk between above- and belowground herbivores in arabidopsis thaliana.plants are often simultaneously infested by several herbivores at the shoots and roots. recent results revealed that the model plant arabidopsis thaliana shows highly challenge-specific local and systemic responses to individual and simultaneous attacks of shoot-infesting aphids and root-infesting nematodes at the metabolome level. (1) here, we present the corresponding transcriptional changes in plants treated with brevicoryne brassicae aphids and heterodera schachtii nematodes individually and ...201425482783
a distinct role of pectate lyases in the formation of feeding structures induced by cyst and root-knot nematodes.pectin in the primary plant cell wall is thought to be responsible for its porosity, charge density, and microfibril spacing and is the main component of the middle lamella. plant-parasitic nematodes secrete cell wall-degrading enzymes that macerate the plant tissue, facilitating the penetration and migration within the roots. in sedentary endoparasitic nematodes, these enzymes are released only during the migration of infective juveniles through the root. later, nematodes manipulate the express ...201424905398
parasitic worms stimulate host nadph oxidases to produce reactive oxygen species that limit plant cell death and promote infection.plants and animals produce reactive oxygen species (ros) in response to infection. in plants, ros not only activate defense responses and promote cell death to limit the spread of pathogens but also restrict the amount of cell death in response to pathogen recognition. plants also use hormones, such as salicylic acid, to mediate immune responses to infection. however, there are long-lasting biotrophic plant-pathogen interactions, such as the interaction between parasitic nematodes and plant root ...201424714570
effects of root herbivory by nematodes on the performance and preference of a leaf-infesting generalist aphid depend on nitrate fertilization.the performance and behavior of herbivores is strongly affected by the quality of their host plants, which is determined by various environmental conditions. we investigated the performance and preference of the polyphagous shoot-infesting aphid myzus persicae on the host-plant arabidopsis thaliana in a two-factorial design in which nitrate fertilization was varied by 33 %, and the root-infesting cyst-nematode heterodera schachtii was present or absent. aphid performance was influenced by these ...201424500735
spatial and temporal expression patterns of auxin response transcription factors in the syncytium induced by the beet cyst nematode heterodera schachtii in arabidopsis.plant-parasitic cyst nematodes induce the formation of a multinucleated feeding site in the infected root, termed the syncytium. recent studies point to key roles of the phytohormone auxin in the regulation of gene expression and establishment of the syncytium. nevertheless, information about the spatiotemporal expression patterns of the transcription factors that mediate auxin transcriptional responses during syncytium formation is limited. here, we provide a gene expression map of 22 auxin res ...201424433277
use of green manure crops and sugar beet varieties to control heterodera betae.although it is less studied than the white beet cyst nematode (heterodera schachtii), the yellow beet cyst nematode (h. betae) has been found in many countries in europe. for example in the netherlands, france and spain. h. betae causes yield losses on sandy soils. a high infestation can result in loss of complete plants. in the netherlands, this nematode is especially found in the south eastern and north eastern part, where it occurs on 18% and 5% of the fields, respectively. from a project of ...201426084110
nondestructive imaging of plant-parasitic nematode development and host response to nematode pathogenesis.the secluded lifestyle of endoparasitic plant nematodes hampers progress toward a comprehensive understanding of plant-nematode interactions. a novel technique that enables nondestructive, long-term observations of a wide range of live nematodes in planta is presented here. as proof of principle, pratylenchus penetrans, heterodera schachtii, and meloidogyne chitwoodi were labeled fluorescently with pkh26 and used to infect arabidopsis thaliana grown in microscopy rhizosphere chambers. nematode b ...201424313744
two closely related members of arabidopsis 13-lipoxygenases (13-loxs), lox3 and lox4, reveal distinct functions in response to plant-parasitic nematode infection.the responses of two closely related members of arabidopsis 13-lipoxygenases (13-loxs), lox3 and lox4, to infection by the sedentary nematodes root-knot nematode (meloidogyne javanica) and cyst nematode (heterodera schachtii) were analysed in transgenic arabidopsis seedlings. the tissue localization of lox3 and lox4 gene expression using β-glucuronidase (gus) reporter gene constructs showed local induction of lox3 expression when second-stage juveniles reached the vascular bundle and during the ...201424286169
interspecific and host-related gene expression patterns in nematode-trapping fungi.nematode-trapping fungi are soil-living fungi that capture and kill nematodes using special hyphal structures called traps. they display a large diversity of trapping mechanisms and differ in their host preferences. to provide insights into the genetic basis for this variation, we compared the transcriptome expressed by three species of nematode-trapping fungi (arthrobotrys oligospora, monacrosporium cionopagum and arthrobotrys dactyloides, which use adhesive nets, adhesive branches or constrict ...201425384908
myo-inositol oxygenase genes are involved in the development of syncytia induced by heterodera schachtii in arabidopsis roots.* in plants, udp-glucuronic acid is synthesized by the oxidation of udp-glucose by udp-glucose dehydrogenase or the oxygenation of free myo-inositol by myo-inositol oxygenase (miox). in arabidopsis, myo-inositol oxygenase is encoded by four genes. transcriptome analysis of syncytia induced by the cyst nematode heterodera schachtii in arabidopsis roots revealed that miox genes are among the most strongly upregulated genes. * we have used beta-glucuronidase (gus) analysis, in situ reverse transcri ...200919691674
do organic amendments enhance the nematode-trapping fungi dactylellina haptotyla and arthrobotrys oligospora?soil cages (polyvinyl chloride pipe with mesh-covered ends) were used to determine how the quantity of two organic amendments affected the nematode-trapping fungi dactylellina haptotyla and arthrobotrys oligospora, which were studied independently in two different vineyards. each cage contained 80 cm(3) of field soil (120 g dry weight equivalent), fungal inoculum (two alginate pellets, each weighing 1.9 mg and containing assimilative hyphae of one fungus), and dried grape or alfalfa leaves (0, 3 ...200419262815
effective delivery of a nematode-repellent peptide using a root-cap-specific promoter.the potential of the mdk4-20 promoter of arabidopsis thaliana to direct effective transgenic expression of a secreted nematode-repellent peptide was investigated. its expression pattern was studied in both transgenic arabidopsis and solanum tuberosum (potato) plants. it directed root-specific β-glucuronidase expression in both species that was chiefly localized to cells of the root cap. use of the fluorescent timer protein dsred-e5 established that the mdk4-20 promoter remains active for longer ...201120602721
quantitative detection of the potato cyst nematode, globodera pallida, and the beet cyst nematode, heterodera schachtii, using real-time pcr with sybr green i dye.the potato cyst nematode globodera pallida and the beet cyst nematode heterodera schachtii are major nematode pests in world agriculture. precise identification and knowledge about the number of nematodes in field soil are necessary to develop effective integrated pest control. here we report the results of the real-time pcr assay for the rapid detection and quantification of g. pallida and h. schachtii. using species specific primers and sybr green i dye, we were able to detect a single second ...200515680208
low cryoprotectant concentrations and fast cooling for nematode cryostorage.cryopreservation protocols based on slow freezing or vitrification often result in cell injury due to ice formation, cell dehydration and/or toxic concentrations of cryoprotectant (cpa). in this study, we present a cryopreservation technique based on low, non-toxic concentrations of cryoprotectants (≈ 2-4m) combined with a rapid cooling rate in the liquid nitrogen phase (-196°c). protocols for successfully cryopreserving the plant parasitic nematodes globodera tabacum tabacum, heterodera schacht ...201121524646
assessment of parasitic activity of fusarium strains obtained from a heterodera schachtii-suppressive soil.this study assessed the potential impact of various fusarium strains on the population development of sugarbeet cyst nematodes. fungi were isolated from cysts or eggs of heterodera schachtii schmidt that were obtained from a field suppressive to that nematode. twenty-six strains of fusarium spp. were subjected to a phylogenic analysis of their rrna-its nucleotide sequences. seven genetically distinct fusarium strains were evaluated for their ability to influence population development of h. scha ...200819259511
cyst nematode parasitism induces dynamic changes in the root epigenome.a growing body of evidence indicates that epigenetic modifications can provide efficient, dynamic, and reversible cellular responses to a wide range of environmental stimuli. however, the significance of epigenetic modifications in plant-pathogen interactions remains largely unexplored. in this study, we provide a comprehensive analysis of epigenome changes during the compatible interaction between the beet cyst nematode heterodera schachtii and arabidopsis (arabidopsis thaliana). whole genome b ...201728298479
Displaying items 1 - 100 of 256