| localization by restriction fragment length polymorphism mapping in potato of a major dominant gene conferring resistance to the potato cyst nematode globodera rostochiensis. | a major dominant locus conferring resistance against several pathotypes of the root cyst nematode globodera rostochiensis was mapped on the linkage map of potato using restriction fragment length polymorphism (rflp) markers. the assessment of resistance versus susceptibility of the plants in the experimental population considered was based on an in vivo (pot) and an in vitro (petri dish) test. by linkage to nine rflp markers the resistance locus gro1 was assigned to the potato linkage group ix w ... | 1990 | 1980523 |
| serological differentiation of the potato-cyst nematodes globodera pallida and g. rostochiensis: ii. preparation and characterization of species specific monoclonal antibodies. | hybridomas producing antibodies which react with thermostable protein antigens isolated from the potato cyst nematode species globodera rostochiensis (tsrop) and g. pallida (tspap) were isolated. three of the isolated hybridomas (wgp 1, wgp 2 and wgp 3) produce antibodies that react with preferent affinity with protein antigens isolated from g. pallida, and two (wgr 11 and wgr 12) produce antibodies which bind preferentially to g. rostochiensis. binding constants were determined to quantitate th ... | 1989 | 2777274 |
| a trans-spliced leader rna sequence in plant parasitic nematodes. | a trans-spliced leader gene has been identified in the genomes of the potato cyst nematodes globodera rostochiensis and g. pallida. the gene contains a 22-nt sequence identical to that of the leader sequence of caenorhabditis elegans, a consensus splice donor site and a putative sm antigen binding site. in common with other nematodes the spliced leader gene is present in tandem repeating units together with the 5s ribosomal rna gene. variation in the length of the intergenic spacer region has pe ... | 1994 | 7838175 |
| the differentiation of parasitic nematodes using random amplified polymorphic dna. | dna from species and races of plant parasitic nematodes (meloidogyne, globodera and heterodera) and a human parasitic nematode (trichinella) were subjected to polymerase chain reaction amplification using one arbitrary primer (m-10). this technique results in relatively simple dna profiles that include polymorphic markers known as random amplified polymorphic dna (rapds). the rapd profiles of the plant nematode species of meloidogyne made possible the identification of m. incognita and m. hapla, ... | 1994 | 7930450 |
| single juveniles of the potato cyst nematodes globodera rostochiensis and g. pallida differentiated by randomly amplified polymorphic dna. | random amplified polymorphic dna (rapd) offers a potential basis for the development of a diagnostic assay to differentiate the potato cyst nematode species globodera rostochiensis and g. pallida. nine decamer primers have been tested for their ability to amplify species-specific dna sequences. primer opg-05 produced 2 discrete dna fragments, which were consistently present in 5 g. rostochiensis populations and absent in 5 g. pallida populations. these fragments were detectable in single females ... | 1993 | 8295795 |
| marker enrichment and high-resolution map of the segment of potato chromosome vii harbouring the nematode resistance gene gro1. | the dominant allele gro1 confers on potato resistance to the root cyst nematode globodera rostochiensis. the gro1 locus has been mapped to chromosome vii on the genetic map of potato, using rflp markers. this makes possible the cloning of gro1 based on its map position. as part of this strategy we have constructed a high-resolution genetic map of the chromosome segment surrounding gro1, based on rflp, rapd and aflp markers. rapd and aflp markers closely linked to gro1 were selected by bulked seg ... | 1995 | 8552038 |
| 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 ... | 1996 | 8589421 |
| genetic mapping of a wide spectrum nematode resistance gene (hero) against globodera rostochiensis in tomato. | the hero gene confers resistance to a wide spectrum of pathotypes of the potato cyst nematode globodera rostochiensis. this gene has been introgressed from the wild tomato species lycopersicon pimpinellifolium into the cultivated tomato. we have used rflp and rapd analysis for the targeted search of the l. pimpinellifolium into the cultivated tomato. we have used rflp and rapd analysis for the targeted search of the l. pimpinellifolium segment. the resistant line la 1792 contains a single introg ... | 1995 | 8664498 |
| 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 |
| electrophysiological analysis of the response of males of the potato cyst nematode, globodera rostochiensis, to fractions of their homospecific sex pheromone. | electrophysiological techniques and behavioural assays were used to determine the response of males of globodera rostochiensis to 4 fractions of the homospecific sex pheromone from virgin females, separated using reverse-phase high-pressure liquid chromatography. sex pheromone activity was confined to 2 of the fractions. the sex pheromone of g. rostochiensis appears to be composed of several weakly basic, polar compounds. | 1997 | 9300469 |
| differential scanning calorimetry studies on the cysts of the potato-cyst nematode globodera rostochiensis during freezing and melting | differential scanning calorimetry (dsc) was used to determine the thermal events associated with freezing and melting of the cysts of the potato-cyst nematode globodera rostochiensis. there were no thermal events during the cooling of dry cysts from 5 to -60 °c and warming back to 5 °c, indicating the absence of water freezing in the dry cysts. during heating of dry cysts from 5 to 80 °c, two overlapping endothermic events were observed at 55 °c, indicating the irreversible destr ... | 1995 | 9320478 |
| changes in the lipid content and fatty acid composition of 2nd-stage juveniles of globodera rostochiensis after rehydration, exposure to the hatching stimulus and hatch. | the total lipid content of the dry weight of whole cysts and 2nd-stage juveniles (j2) of globodera rostochiensis was 17.1% in dry cysts, 20.9% in cysts soaked in distilled water (dw), 20.3% in cysts that had been in potato root diffusate (prd) for 7 days, 7.3% in cysts that had been in prd for 28 days and 29.2% for hatched j2. the fatty acid composition of the total lipid did not differ between dry cysts, cysts in dw and cysts in prd for 7 days. however, major differences in the fatty acid compo ... | 1998 | 9509028 |
| endogenous cellulases in animals: isolation of beta-1, 4-endoglucanase genes from two species of plant-parasitic cyst nematodes. | beta-1,4-endoglucanases (egases, ec 3.2.1.4) degrade polysaccharides possessing beta-1,4-glucan backbones such as cellulose and xyloglucan and have been found among extremely variegated taxonomic groups. although many animal species depend on cellulose as their main energy source, most omnivores and herbivores are unable to produce egases endogenously. so far, all previously identified egase genes involved in the digestive system of animals originate from symbiotic microorganisms. here we report ... | 1998 | 9560201 |
| the effect of long term storage on the lipid reserves and fatty acid composition of cysts and hatched juveniles of globodera rostochiensis g. pallida | the lipid composition of three batches of single generation cysts of globodera rostochiensis, stored dry at 4 degreesc for 1, 7 and 13 years, comprised 81%, 74% and 53% neutral lipids, 14%, 18% and 27% non-acidic phospholipids and 5%, 8% and 20% free fatty acids, respectively. lipids in eggs from two batches of g. pallida cysts, stored for 3 and 7 years, comprised 80% and 67% neutral lipids, 15% and 23% non-acidic phospholipids and 5% and 10% free fatty acids, respectively. all batches contained ... | 1998 | 9687594 |
| genomic organization of four beta-1,4-endoglucanase genes in plant-parasitic cyst nematodes and its evolutionary implications. | the genomic organization of genes encoding beta-1,4-endoglucanases (cellulases) from the plant-parasitic cyst nematodes heterodera glycines and globodera rostochiensis (hg-eng1, hg-eng2, gr-eng1, and gr-eng2) was investigated. hg-eng1 and gr-eng1 both contained eight introns and structural domains of 2151 and 2492bp, respectively. hg-eng2 and gr-eng2 both contained seven introns and structural domains of 2324 and 2388bp, respectively. no significant similarity in intron sequence or size was obse ... | 1998 | 9767113 |
| cloning of a trans-spliced glyceraldehyde-3-phosphate-dehydrogenase gene from the potato cyst nematode globodera rostochiensis and expression of its putative promoter region in caenorhabditis elegans. | reverse genetics to determine the relative importance of individual pathogenicity factors of the potato cyst nematode globodera rostochiensis depends, apart from an efficient transformation protocol for this obligatory plant parasite, on the availability of an efficient promoter. pcr-based cloning was used to isolate a cdna encoding glyceraldehyde-3-phosphate-dehydrogenase (gapdh, a crucial enzyme in glycolysis and gluconeogenesis; this gene was designated gpd) and its 5'-flanking region. the cd ... | 1998 | 9851607 |
| direct analysis of the secretions of the potato cyst nematode globodera rostochiensis. | secretions were induced from second (invasive) stage juveniles (j2s) of the potato cyst nematode globodera rostochiensis by exposing them to 5-methoxy-n,n-dimethyl tryptamine oxalate (dmt). secretions were collected from j2s in sufficient quantity to allow direct analysis. gel electrophoresis followed by monochromatic silver staining demonstrated the presence of at least 10 proteins. the presence of several enzymes, including superoxide dismutase and proteases, was demonstrated using western blo ... | 1999 | 10466124 |
| linkage analysis by genotyping of sibling populations: a genetic map for the potato cyst nematode constructed using a "pseudo-f2" mapping strategy. | a mapping strategy is described for the construction of a linkage map of a non-inbred species in which individual offspring genotypes are not amenable to marker analysis. after one extra generation of random mating, the segregating progeny was propagated, and bulked populations of offspring were analyzed. although the resulting population structure is different from that of commonly used mapping populations, we show that the maximum likelihood formula for a normal f2 is applicable for the estima ... | 1999 | 10485294 |
| naturally induced secretions of the potato cyst nematode co-stimulate the proliferation of both tobacco leaf protoplasts and human peripheral blood mononuclear cells. | naturally induced secretions from infective juveniles of the potato cyst nematode globodera rostochiensis co-stimulate the proliferation of tobacco leaf protoplasts in the presence of the synthetic phytohormones alpha-naphthaleneacetic acid (naa) and 6-benzylaminopurine (bap). with the use of a protoplast-based bioassay, a low-molecular-weight peptide(s) (< 3 kda) was shown to be responsible for the observed effect. this mitogenic oligopeptide(s) is functionally dissimilar to auxin and cytokinin ... | 1999 | 10517027 |
| an efficient cdna-aflp-based strategy for the identification of putative pathogenicity factors from the potato cyst nematode globodera rostochiensis. | a new strategy has been designed to identify putative pathogenicity factors from the dorsal or subventral esophageal glands of the potato cyst nematode globodera rostochiensis. three independent criteria were used for selection. first, genes of interest should predominantly be expressed in infective second-stage juveniles, and not, or to a far lesser extent, in younger developmental stages. for this, gene expression profiles from five different developmental stages were generated with cdna-aflp ... | 2000 | 10939254 |
| cloning, expression and functional characterisation of a peroxiredoxin from the potato cyst nematode globodera rostochiensis. | we report the cloning, expression and functional characterisation of a peroxidase belonging to the peroxiredoxin family from the potato cyst nematode globodera rostochiensis, the first molecule of this type from any nematode parasitic on plants. the g. rostochiensis peroxiredoxin catalyses the breakdown of hydrogen peroxide, but not cumene or t-butyl hydroperoxide, in a trypanosomatid reducing system comprising trypanothione reductase, trypanothione and tryparedoxin. in common with its homologue ... | 2000 | 11087915 |
| genest, a powerful bidirectional link between cdna sequence data and gene expression profiles generated by cdna-aflp. | the release of vast quantities of dna sequence data by large-scale genome and expressed sequence tag (est) projects underlines the necessity for the development of efficient and inexpensive ways to link sequence databases with temporal and spatial expression profiles. here we demonstrate the power of linking cdna sequence data (including est sequences) with transcript profiles revealed by cdna-aflp, a highly reproducible differential display method based on restriction enzyme digests and selecti ... | 2001 | 11266565 |
| water relations during desiccation of cysts of the potato-cyst nematode globodera rostochiensis. | the loss during desiccation of osmotically active water (oaw), which freezes during cooling to -45 degrees c, and osmotically inactive water (oiw), which remains unfrozen, from the cysts of the potato cyst nematode, globodera rostochiensis, was determined using differential scanning calorimetry. exotherms and endotherms associated with non-egg compartments were not detected after 5 min desiccation at 50% relative humidity and 20 degrees c. the pattern of water loss from the cysts indicates that ... | 2001 | 11302528 |
| analysis of the sensory responses of parasitic nematodes using electrophysiology. | use of the electrophysiological technique to examine the sensory perception of live, intact nematodes has provided detailed analysis of responses to known concentrations of test chemicals. the use of larger nematodes, such as the animal-parasite syngamus trachea, enabled direct extracellular recordings from individual sensilla; with smaller nematodes, the recording electrode was inserted close to the cephalic region. extracellular recordings from the cephalic region of second-stage juveniles and ... | 2001 | 11406140 |
| fmrfamide-related peptides in potato cyst nematodes. | this study presents data demonstrating the presence of fmrfamide-related peptides (farps) in potato cyst nematodes (pcn). five transcripts of farp encoding genes, designated gpflp-1 to gpflp-5, were characterised using race. in terms of orfs, gpflp-1 was 444 base pairs (bp) long and coded for four copies of the farp, pf3 (ksaymrfamide) whilst gpflp-2 was 309 bp long and encoded one copy of the peptide, knkfefirfamide. gpflp-3 (420 bp) encoded two copies of kheylrfamide (af2) and the genes gpflp- ... | 2001 | 11522352 |
| evaluation of pcr, ief and elisa techniques for the detection and identification of potato cyst nematodes from field soil samples in england and wales. | effective management of potato cyst nematodes (pcns) requires simple, rapid and accurate identification and quantification of field populations. soil samples from a survey of 484 fields in potato rotations in england and wales were used to compare the identification and quantification of pcns using ief, pcr, elisa and bait plant tests. the cyst counts and bait plant test revealed that 64.3% of field samples contained pcns. bait plant tests increased the detection rate of pcns in field samples by ... | 2001 | 11721525 |
| effects of intact glucosinolates and products produced from glucosinolates in myrosinase-catalyzed hydrolysis on the potato cyst nematode (globodera rostochiensis cv. woll). | the potato cyst nematode (globodera rostochiensis cv. woll) is responsible for large yield losses in the potato crop, and opportunities for reducing the attack of these plant nematode species are, therefore, important. this study has been devoted to the testing of the in vitro effects on the potato cyst nematode of eight glucosinolates [prop-2-enyl-, but-3-enyl-, (r)-4-methylsulfinylbut-3-enyl-, benzyl-, phenethyl-, 4-hydroxybenzyl-, (2s)-2-hydroxybut-3-enyl-, and (2r)-2-hydroxy-2-phenylethylglu ... | 2002 | 11829629 |
| the broad-spectrum potato cyst nematode resistance gene (hero) from tomato is the only member of a large gene family of nbs-lrr genes with an unusual amino acid repeat in the lrr region. | the hero gene of tomato is a broad spectrum resistance gene that confers a high level of resistance to all pathotypes of the potato cyst nematodes globodera rostochiensis and partial resistance to g. pallida. the gene was identified by map-based cloning, sequencing and complementation analysis of two susceptible tomato lines with an array of 13 overlapping cosmids spanning a total distance of 135 kb. hero encodes a protein with a nucleotide-binding site (nbs) and a leucine-rich-repeat (lrr) doma ... | 2002 | 12121443 |
| effects of phytohormones on the surfaces of plant-parasitic nematodes. | the direct effects of phytohormones (auxin and kinetin) and root diffusates on the surface lipophilicity of the plant parasitic nematodes globodera rostochiensis and meloidogyne incognita were investigated. the fluorescent lipid probe af18 (5-n(octodecanoyl) aminofluorescein) was used to detect surface changes. root diffusates increased af18 uptake by g. rostochiensis while it had no effect on m. incognita. kinetin and auxin decreased af18 uptake in g. rostochiensis, while they had the opposite ... | 2002 | 12211609 |
| monoclonal antibodies reactive with secreted-excreted products from the amphids and the cuticle surface of globodera pallida affect nematode movement and delay invasion of potato roots. | this paper describes excreted-secreted proteins (es) proteins that were immunolocalised in the cuticle, amphids and subventral glands of second stage juveniles of the two species of potato cyst nematodes (globodera pallida and globodera rostochiensis). monoclonal antibodies reactive with these es proteins were used in a bioassay to investigate their effect on nematode movement and on their ability to invade potato roots. antibodies recognising the nematode cuticle surface and the amphids affecte ... | 2002 | 12464417 |
| mapping qtls for resistance to the cyst nematode globodera pallida derived from the wild potato species solanum vernei. | resistance to the potato cyst nematode (pcn) species globodera pallida, derived from the wild diploid potato species solanum vernei, has been investigated. this source of resistance, which is effective against all of the major pathotypes of g. pallida and globodera rostochiensis, has been assumed to be due to several genetic factors, but it has proved difficult to deploy effectively in breeding strategies for potato cultivars. diploid and tetraploid potato populations segregating for 'vernei' re ... | 2002 | 12582563 |
| a sequential approach to risk assessment of transgenic plants expressing protease inhibitors: effects on nontarget herbivorous insects. | protease inhibitors expressed in transgenic plants can provide enhanced levels of resistance to important pest species. a sequential approach for testing the effects of protease inhibitor-expressing crops on nontarget herbivorous insects has been developed. the approach consists of five tiers. the first two tiers comprise the selection phase. in tier one, field surveys are used to characterise the nontarget invertebrate fauna of a crop. in tier 2, histochemical assays are used to identify the su ... | 2003 | 12885165 |
| glutathione peroxidases of the potato cyst nematode globodera rostochiensis. | we report the cloning and characterisation of full-length dnas complementary to rna (cdnas) encoding two glutathione peroxidases (gpxs) from a plant parasitic nematode, the potato cyst nematode (pcn) globodera rostochiensis. one protein has a functional signal peptide that targets the protein for secretion from animal cells while the other is predicted to be intracellular. both genes are expressed in all parasite stages tested. the mrna encoding the intracellular gpx is present throughout the ne ... | 2004 | 14693370 |
| plant degradation: a nematode expansin acting on plants. | expansin proteins, which have so far been identified only in plants, rapidly induce extension of plant cell walls by weakening the non-covalent interactions that help to maintain their integrity. here we show that an animal, the plant-parasitic roundworm globodera rostochiensis, can also produce a functional expansin, which it uses to loosen cell walls when invading its host plant. as this nematode is known to be able to disrupt covalent bonds in plant cell walls, its accompanying ability to loo ... | 2004 | 14702076 |
| early responses of resistant and susceptible potato roots during invasion by the potato cyst nematode globodera rostochiensis. | signals from roots of resistant (cv. maris piper) and susceptible (cv. désirée) potato cultivars during invasion by second stage juveniles (j2s) of the potato cyst nematode, globodera rostochiensis, were investigated. novel experimental chambers enabled the recording of electrophysiological responses from roots during nematode invasion. the root cell membrane potentials were maintained throughout the 3 d required to assess invasion and feeding site development. the steady-state resting membrane ... | 2004 | 14754919 |
| a high-resolution map of the h1 locus harbouring resistance to the potato cyst nematode globodera rostochiensis. | the resistance gene h1 confers resistance to the potato cyst nematode globodera rostochiensis and is located at the distal end of the long arm of chromosome v of potato. for marker enrichment of the h1 locus, a bulked segregant analysis (bsa) was carried out using 704 aflp primer combinations. a second source of markers tightly linked to h1 is the ultra-high-density (uhd) genetic map of the potato cross sh x rh. this map has been produced with 387 aflp primer combinations and consists of 10,365 ... | 2004 | 14985978 |
| molecular cloning of the potato gro1-4 gene conferring resistance to pathotype ro1 of the root cyst nematode globodera rostochiensis, based on a candidate gene approach. | the endoparasitic root cyst nematode globodera rostochiensis causes considerable damage in potato cultivation. in the past, major genes for nematode resistance have been introgressed from related potato species into cultivars. elucidating the molecular basis of resistance will contribute to the understanding of nematode-plant interactions and assist in breeding nematode-resistant cultivars. the gro1 resistance locus to g. rostochiensis on potato chromosome vii co-localized with a resistance-gene ... | 2004 | 15078331 |
| novel matrix metalloproteinase from the cyst nematodes heterodera glycines and globodera rostochiensis. | | 2004 | 15138072 |
| the potential signalling pathways which regulate surface changes induced by phytohormones in the potato cyst nematode (globodera rostochiensis). | it has been demonstrated that the surface lipophilicity of the plant-parasitic nematode globodera rostochiensis decreases when infective larvae are exposed to the phytohormones indole-3-acetic acid (auxin) or kinetin (cytokinin). in the present study, it was shown that inhibition of phospholipase c (plc) or phosphatidylinositol 3 kinase (pi3-kinase) reversed the effect of phytohormones on surface lipophilicity. the signalling pathway(s) involved in surface modification were investigated using 'c ... | 2004 | 15180321 |
| hygienization of municipal sludge in automatically operated chamber filter presses with thermal vacuum drying. | this paper presents the state of the art of thermal vacuum drying in chamber filter presses for unattended automatic operation. the achieved results are exemplified by the treatment of the two stage digested combined primary, chemical and biological sludge created by the veas concept for nutrient removal from municipal wastewater at veas. the water removal rate in each stage of the drying process is described, with comments on the low energy needs. the advantages of one-sided heating, the capaci ... | 2004 | 15553459 |
| characterization of susceptibility and resistance responses to potato cyst nematode (globodera spp.) infection of tomato lines in the absence and presence of the broad-spectrum nematode resistance hero gene. | the tomato hero a gene is the only member of a multigene family that confers a high level (>80%) of resistance to all the economically important pathotypes of potato cyst nematode (pcn) species globodera rostochiensis and g. pallida. although the resistance levels of transgenic tomato lines were similar to those of the tomato line la1792 containing the introgressed hero multigene family, transgenic potato plants expressing the tomato hero a gene are not resistant to pcns. comparative microscopy ... | 2005 | 15720085 |
| origin, distribution and 3d-modeling of gr-expb1, an expansin from the potato cyst nematode globodera rostochiensis. | southern analysis showed that gr-expb1, a functional expansin from the potato cyst nematode globodera rostochiensis, is member of a multigene family, and est data suggest expansins to be present in other plant parasitic nematodes as well. homology modeling predicted that gr-expb1 domain 1 (d1) has a flat beta-barrel structure with surface-exposed aromatic rings, whereas the 3d structure of gr-expb1-d2 was remarkably similar to plant expansins. gr-expb1 shows highest sequence similarity to two ex ... | 2005 | 15848187 |
| functional analysis of pathogenicity proteins of the potato cyst nematode globodera rostochiensis using rnai. | rna interference (rnai) has been used widely as a tool for examining gene function and a method that allows its use with plant-parasitic nematodes recently has been described. here, we use a modified method to analyze the function of secreted beta-1,4, endoglucanases of the potato cyst nematode globodera rostochiensis, the first in vivo functional analysis of a pathogenicity protein of a plant-parasitic nematode. knockout of the beta-1,4, endoglucanases reduced the ability of the nematodes to in ... | 2005 | 16042007 |
| role of 2,4-diacetylphloroglucinol in the interactions of the biocontrol pseudomonad strain f113 with the potato cyst nematode globodera rostochiensis. | the potato cyst nematode globodera rostochiensis is an important pest of potato (solanum tuberosum). pseudomonas fluorescens f113, which produces 2,4-diacetylphloroglucinol (dapg), was investigated as a potential biocontrol agent against g. rostochiensis. exposure of nematode cysts to the pseudomonad, under in vitro conditions or in soil microcosms, almost doubled the ability of the eggs to hatch. the percentage of mobile juveniles was reduced threefold following their incubation in the presence ... | 1997 | 16535571 |
| marker-assisted combination of major genes for pathogen resistance in potato. | closely linked pcr-based markers facilitate the tracing and combining of resistance factors that have been introgressed previously into cultivated potato from different sources. crosses were performed to combine the ry ( adg ) gene for extreme resistance to potato virus y (pvy) with the gro1 gene for resistance to the root cyst nematode globodera rostochiensis and the rx1 gene for extreme resistance to potato virus x (pvx), or with resistance to potato wart (synchytrium endobioticum). marker-ass ... | 2006 | 16538512 |
| 'candidatus paenicardinium endonii', an endosymbiont of the plant-parasitic nematode heterodera glycines (nemata: tylenchida), affiliated to the phylum bacteroidetes. | bacteria-like endosymbionts of females of the plant-parasitic nematodes globodera rostochiensis and heterodera goettingiana and juveniles of heterodera glycines were first observed during transmission electron microscopy (tem) studies conducted in the 1970s. these organisms were characterized as being rod-shaped, ranging in size from 0.3 to 0.5 microm in diameter and 1.8 to 3 microm in length and containing structures labelled as striated inclusion bodies or tubular structures. a population of h ... | 2006 | 16825653 |
| comparative serial analysis of gene expression of transcript profiles of tomato roots infected with cyst nematode. | we analyzed global transcripts for tomato roots infected with the cyst nematode globodera rostochiensis using serial analysis of gene expression (sage). sage libraries were made from nematode-infected roots and uninfected roots at 14 days after inoculation, and the clones including sage tags were sequenced. genes were identified by matching the sage tags to tomato expressed sequence tags and cdna databases. we then compiled a list of numerous genes according to the mrna levels that were altered ... | 2007 | 16983456 |
| functionality of resistance gene hero, which controls plant root-infecting potato cyst nematodes, in leaves of tomato. | the expression of host genomes is modified locally by root endoparasitic nematode secretions to induce the development of complex cellular structures referred as feeding sites. in compatible interactions, the feeding sites provide the environment and nutrients for the completion of the nematode's life cycle, whereas in an incompatible (resistant) interaction, the host immune system triggers a plant cell death programme, often in the form of a hypersensitive reaction, which restricts nematode rep ... | 2006 | 17080958 |
| molecular variation in the potato cyst nematode, globodera pallida, in relation to virulence. | the potato cyst nematode globodera pallida poses a challenge for potato growers. the potato cyst nematodes (pcn) globodera rostochiensis and g. pallida cause damage valued at over pounds 50m per annum in the u.k. and problems in controlling pcn are growing due to the increase in populations and spread of g. pallida, the lack of many commercially attractive cultivars with resistance to this species and the pressure to reduce nematicide use. over 60% of potato fields in the u.k. are infected with ... | 2006 | 17390803 |
| immunomodulating effect of elicitors and suppressors upon infection of potato with globodera rostochiensis (wollenweber, 1923) beherens, 1975. | | 2006 | 17425036 |
| nematicidal effects of cysteine proteinases against sedentary plant parasitic nematodes. | cysteine proteinases from the fruit and latex of plants, such as papaya, pineapple and fig, have previously been shown to have substantial anthelmintic efficacy, in vitro and in vivo, against a range of animal parasitic nematodes. in this paper, we describe the in vitro effects of these plant extracts against 2 sedentary plant parasitic nematodes of the genera meloidogyne and globodera. all the plant extracts examined caused digestion of the cuticle and decreased the activity of the tested nemat ... | 2007 | 17640402 |
| sequence and characterization of six mitochondrial subgenomes from globodera rostochiensis: multipartite structure is conserved among close nematode relatives. | recently, a multipartite mitochondrial genome was characterized in the potato cyst nematode, globodera pallida. six subgenomic circles were detectable by pcr, while full-length genomes were not. we investigate here whether this subgenomic organization occurs in a close relative of g. pallida. we amplified and sequenced one entire mitochondrial subgenome from the cyst-forming nematode, globodera rostochiensis. comparison of the noncoding region of this subgenome with those reported previously for ... | 2007 | 17674076 |
| 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 ... | 2008 | 17920621 |
| two tomato alpha-expansins show distinct spatial and temporal expression patterns during development of nematode-induced syncytia. | cyst nematodes induce specific syncytial feeding structures within the root which develop from an initial cell by successive incorporation of neighbouring cells through local cell wall dissolutions followed by hypertrophy of included cells. expansins are known to induce cell wall relaxation and extension in acidic ph, and they are involved in many processes requiring wall modification from cell expansion to cell wall disassembly. we studied the expression pattern of tomato (lycopersicon esculent ... | 2008 | 18275468 |
| poly(t) variation within mitochondrial protein-coding genes in globodera (nematoda: heteroderidae). | we sequenced a mitochondrial subgenome from the nematode globodera rostochiensis, in two overlapping pieces. the subgenome was 9210 bp and contained four protein-coding genes (nd4, coiii, nd3, cytb) and two trna genes (trna(thr), trna(gln)). genome organization was similar to that of globodera pallida, which is multipartite. together with the small number of genes on this subgenome, this suggests that the mitochondrial genome of g. rostochiensis is also multipartite. in the initial clones sequen ... | 2008 | 18288437 |
| comparison of british populations of potato cyst nematodes with populations from continental europe and south america using rapds. | genetic variation between populations of globodera pallida, primarily from britain but including populations from continental europe and south america and two globodera rostochiensis populations, was examined using random amplified polymorphic dna (rapd). fourteen primers were used and 250 amplification products observed. a comparison was made of the similarities between the species and, within g. pallida, between populations from britain, the netherlands, germany, and switzerland, of the pathot ... | 1997 | 18464829 |
| identification of rflp markers linked to the h1 gene conferring resistance to the potato cyst nematode globodera rostochiensis. | the h1 gene from solanum tuberosum ssp. andigena confers high levels of resistance to the potato cyst nematode globodera rostochiensis and is used extensively in potato breeding. using a dihaploid segregating population, a search was conducted for linkage between this gene and markers on the potato/tomato rflp map. a total of 60 rflp markers covering the entire genome were screened on bulk resistant and susceptible segregants. linkage was indicated for eight markers on chromosome 5. individual p ... | 1993 | 18469978 |
| taqman real-time pcr-based approach for differentiation between globodera rostochiensis (golden nematode) and globodera artemisiae species. | cyst nematodes from the genus globodera are common, and widely distributed parasites of solaraceae. intact cysts persist in soil even up to 10 years without detriment. out of two globodera species occurring in poland, globodera rostochiensis is considered by european and mediterranean plant protection organization (eppo) as a quarantine pest, while globodera artemisiae is not. therefore, the distinction between these two species is crucial. classic methods of detection and differentiation are la ... | 2008 | 18483815 |
| expression of two functionally distinct plant endo-beta-1,4-glucanases is essential for the compatible interaction between potato cyst nematode and its hosts. | for the proliferation of their feeding sites (syncytia), the potato cyst nematode globodera rostochiensis is thought to recruit plant endo-beta-1,4-glucanases (egases, ec. 3.2.1.4). reverse-transcription polymerase chain reaction experiments on tomato (solanum lycopersicum) indicated that the expression of two out of the at least eight egases, namely sl-cel7 and sl-cel9c1, is specifically upregulated during syncytium formation. in situ hybridization and immunodetection studies demonstrated that ... | 2008 | 18624642 |
| [genetic variability and differentiation of three russian populations of yellow potato cyst nematode globodera rostochiensis as revealed by nuclear markers]. | genetic variability of yellow potato cyst nematode g. rostochiensis from three russian populations (karelia, vladimir oblast, and moscow oblast) was investigated using two types of nuclear markers. using rapd markers identified with the help of six random primers (p-29, opa-10, opt-14, opa-11, opb-11, and oph-20), it was possible to distinguish karelian population from the group consisting of the populations from two adjacent regions (moscow oblast and vladimir oblast). based on the combined mat ... | 2008 | 18672794 |
| alternative splicing: a novel mechanism of regulation identified in the chorismate mutase gene of the potato cyst nematode globodera rostochiensis. | chorismate mutase (cm) secreted from the stylet of plant-parasitic nematodes plays an important role in plant parasitism. we isolated and characterized a new nematode cm gene (gr-cm-1) from the potato cyst nematode, globodera rostochiensis. the gr-cm-1 gene was found to exist in the nematode genome as a single-copy gene that has two different alleles, gr-cm-1a and gr-cm-1b, both of which could give rise to two different mrna transcripts of gr-cm-1 and gr-cm-1-irii. in situ mrna hybridization sho ... | 2008 | 18786575 |
| development and evaluation of sampling methods for fields with infestation foci of potato cyst nematodes (globodera rostochiensis and g. pallida). | abstract a computer program, sample, was developed to evaluate existing and create new sampling methods for the detection of infestation foci of the potato cyst nematode (globodera rostochiensis and g. pallida). by combining a model for the medium-scale distribution of cysts that provides the expected population densities at each position within the focus and a model for the small-scale distribution within square meters, sampling procedures can be simulated. the importance of the parameters of t ... | 2000 | 18944545 |
| a model for infestation foci of potato cyst nematodes globodera rostochiensis and g. pallida. | abstract infestation foci of potato cyst nematodes (globodera rostochiensis and g. pallida) in the provinces of zeeland, friesland, groningen, and drente of the netherlands were sampled to validate a model describing infestation foci based on data from flevoland. eighty-two fields were presampled to locate infestation foci using a coarse sampling grid (8 x 3 m). parts of 37 fields containing one or more foci were sampled intensively by extracting at least 1.5 kg of soil per square meter (1.33 x ... | 1999 | 18944694 |
| potato root diffusate-induced secretion of soluble, basic proteins originating from the subventral esophageal glands of potato cyst nematodes. | abstract in preparasitic second-stage juveniles (j(2)) of potato cyst nematode globodera rostochiensis, six proteins with molecular masses of 30, 31a/b, 32, 39, and 49 kda were recognized on western blots by a monoclonal antibody (mgr48) specific for the subventral esophageal glands. all of these subventral gland proteins (svp's) focused in the basic range (pi 6.8 to 8.6) of an immobilized ph gradient. western blotting showed that the svp's were present in preparasitic and parasitic j(2) and not ... | 1997 | 18945052 |
| genotype-dependent expression of specific members of potato protease inhibitor gene families in different tissues and in response to wounding and nematode infection. | protease inhibitors (pis) are small ubiquitous proteins with a variety of biological functions in plants, including protein stabilization, modulation of apoptosis and defense against pathogens. kunitz-like inhibitors (pkpis) and proteinase inhibitors 1 (pi-1) are abundant in storage organs of potato plants and are up-regulated in other tissues in response to biotic and abiotic stress. however, little information is available on genotype-dependent regulation of individual pkpi group- and pi-1 gen ... | 2009 | 19095329 |
| a secreted spry domain-containing protein (sprysec) from the plant-parasitic nematode globodera rostochiensis interacts with a cc-nb-lrr protein from a susceptible tomato. | esophageal gland secretions from nematodes are believed to include effectors that play important roles in plant parasitism. we have identified a novel gene family encoding secreted proteins specifically expressed in the dorsal esophageal gland of globodera rostochiensis early in the parasitic cycle, and which contain the b30.2/spry domain. the secondary structure of these proteins, named the secreted spry domain-containing proteins (sprysec), includes highly conserved regions folding into beta-s ... | 2009 | 19245327 |
| identification and characterization of the most abundant cellulases in stylet secretions from globodera rostochiensis. | plant-parasitic cyst nematodes secrete cell wall modifying proteins during their invasion of host plants. in this study, we used a monoclonal antibody to immunopurify and to sequence the n terminus of the most abundant cellulases in stylet secretions of preparasitic juveniles of globodera rostochiensis. the n-terminal amino acid sequence perfectly matched the sequence of an expressed sequence tag of two nearly identical genes, named gr-eng3 and gr-eng4, which show relatively low similarity with ... | 2009 | 19245333 |
| morphological and molecular identification of globodera pallida associated with potato in idaho. | the identity of a newly discovered population of pale potato cyst nematode globodera pallida associated with potato in eastern idaho was established by morphological and molecular methods. morphometrics of cysts and second-stage juveniles were generally within the expected ranges for g. pallida with some variations noted. the idaho population and paratype material from epworth, lincolnshire, england, both showed variations in tail shape, with bluntly rounded to finely pointed tail termini. compa ... | 2007 | 19259482 |
| comparative efficiency of the fenwick can and schuiling centrifuge in extracting nematode cysts from different soil types. | the fenwick can and schuiling centrifuge are widely used to extract nematode cysts from soil samples. the comparative efficiencies of these two methods during cyst extraction have not been determined for different soil types under different cyst densities. such information is vital for statutory laboratories that must choose a method for routine, high-throughput soil monitoring. in this study, samples of different soil types seeded with varying densities of potato cyst nematode (globodera rostoc ... | 2008 | 19259516 |
| molecular characterization of aldolase from heterodera glycines and globodera rostochiensis. | fructose-bisphosphate aldolase (ec 4.1.2.13) is a key enzyme in glycolysis. we have characterized full-length coding sequences for aldolase genes from the cyst nematodes heterodera glycines and globodera rostochiensis, the first for any plant-parasitic nematode. nucleotide homology is high (83% identity), and the respective sequences encode 40 kda proteins with 89% amino acid identity. genomic sequences contain six introns located at identical positions in both genes. intron 4 in the h. glycines ... | 2005 | 19262876 |
| phylogenetic relationships based on ribosomal dna data for four species of cyst nematodes from italy and one from syria. | phylogenetic analysis of new ribosomal dna (rdna) data for heterodera mediterranea, h. hordecalis, h. carotae, and h. fici from italy and h. ciceri from syria, along with published data for other species, showed high bootstrap support for the following relationships: (((((h. carotae h. cruciferae) h. goettingiana) (((h. trifolii h. ciceri) h. mediterranea) ((h. avenae h. latipons) h. fici))) (cactodera betulae h. hordecalis)) (globodera rostochiensis g. pallida)). the rdna sequence data were for ... | 2001 | 19265879 |
| comparative responses of globodera rostochiensis and g. pallida to hatching chemicals. | globodera rostochiensis and g. pallida responded similarly to hatch stimulation by potato root leachate, but proportionally more second-stage juveniles (j2s) of g. rostochiensis hatched than of g. pallida in response to picrolonic acid, sodium thiocyanate, alpha-solanine, and alpha-chaconine. fractionation of the potato root leachate identified hatching factors with species-selective (active toward both species but stimulating greater hatch of one species than the other), -specific (active towar ... | 2001 | 19265881 |
| cloning of a putative pectate lyase gene expressed in the subventral esophageal glands of heterodera glycines. | we report the cloning of a heterodera glycines cdna that has 72% identity at the amino acid level to a pectate lyase from globodera rostochiensis. in situ hybridizations showed that the corresponding gene (hg-pel-1) is expressed in the subventral esophageal gland cells of second-stage juveniles. the deduced amino acid sequence of the h. glycines cdna shows homology to class iii pectate lyases of bacterial and fungal origin. | 2002 | 19265900 |
| an algorithm for optimizing rotational control of globodera rostochiensis on potato crops in bolivia. | the outline area of new cysts of globodera rostochiensis was measured by image analysis. a linear regression of this value against egg content provided a basis for adjusting the egg number for cyst size. this adjusted egg content provides an estimate of the relative fullness of a cyst with eggs. this value showed an exponential decline in eggs over 3.5 years since the last potato crop. it corresponds to an average loss in the dormant egg population of 32.8 +/- 5.6%/year for 26 fields at toralapa ... | 2001 | 19266007 |
| the influence of potato cultivar on lipid content and fecundity of bolivian and british populations of globodera rostochiensis. | the influence of host cultivar on the lipid levels provided by a female to her progeny was investigated with oil red o stain and a quantitative image analyzer. a population of globodera rostochiensis was multiplied at toralapa field station in bolivia on 25 different potato cultivars grown in that country. the mean neutral lipid content of newly formed second-stage juveniles varied significantly with cultivar over a 200% range. the corresponding range was only 18% and 28% for the same bolivian a ... | 1999 | 19270908 |
| 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 ... | 1997 | 19274144 |
| effect of initial nematode density on managing globodera rostochiensis with resistant cultivars and nonhosts. | cropping systems in which resistant potato cultivars were grown at different frequencies in rotation with susceptible cultivars and a nonhost (oats) were evaluated at four initial nematode population densities (pi) for their ability to maintain globodera rostochiensis at a target level of <0.2 egg/cm(3) of soil. at a pi of 0.1 to 1 egg/cm(3) of soil, cropping systems with 2 successive years of a resistant cultivar every 3 years of potato production reduced and maintained g. rostochiensis at <0.2 ... | 1996 | 19277169 |
| lipid composition of cyst stages of globodera rostochiensis. | lipid compositional analysis was conducted on the white, yellow, and brown cyst stages of globodera rostochiensis (golden cyst nematode). triacylglycerols were the largest lipid fraction in all stages examined, ranging from 55-75% of total lipid. ethanolamine phosphoglycerides and choline phosphoglycerides were present in high amounts in all cyst fractions, with a total phospholipid content of 20%, 14.7%, and 12.8% in the white, yellow, and brown cyst stages, respectively. sterols, steryl esters ... | 1995 | 19277293 |
| effects of inoculum density and egg age on establishment of globodera rostochiensis populations. | the establishment of globodera rostochiensis rol populations was examined under greenhouse conditions. the probability of g. rostochiensis population establishment was calculated from the number of plants that produced new cysts with viable eggs following inoculation with various numbers of eggs of different ages. probability of population establishment was positively correlated with inoculum density but was not affected by the age of eggs used in these experiments. the probability of g. rostoch ... | 1993 | 19279770 |
| probability of globodera rostochiensis spread on equipment and potato tubers. | the probability of spreading cysts of globodera rostochiensis on farming equipment and potato tubers was investigated in naturally infested field plots. the number of cysts recovered from soil that adhered to equipment differed significantly between different pieces of equipment. these differences were related to initial nematode density and, in most cases, to the volume of soil that adhered to the equipment. at an initial density of 0.04 egg/cm(3) of soil, significantly more cysts were recovere ... | 1993 | 19279771 |
| major sperm protein genes from globodera rostochiensis. | three genes in the major sperm protein (msp) gene family from the potato cyst nematode globodera rostochiensis were cloned and sequenced. in contrast to the absence of introns in caenorhabditis elegans msp genes, these genes in g. rostochiensis contained a 57 nucleotide intron, with normal exon-intron boundaries, in the same relative location as the intron in onchocerca volvulus. the msp genes of g. rostochiensis had putative caat, tata, and polyadenylation signals. the predicted g. rostochiensi ... | 1993 | 19279808 |
| 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 |
| serological differentiation of plant-parasitic nematode species with polyclonal and monoclonal antibodies. | although several attempts have been made to differentiate nematode species with polyclonal antisera, these efforts thus far have met with limited success because of extensive crossreactivities of the sera. since the hybridoma technique offers the opportunity to develop more specific serological reagents, some research groups have recently started to apply this technology to the problem of species identification in nematology. monoclonal antibodies (ma) that differentiate the potato-cyst nematode ... | 1990 | 19287684 |
| reproduction of globodera rostochiensis on transformed roots of solanum tuberosum cv. desiree. | transformed roots of the susceptible potato solanum tuberosum l. cv. desiree were inoculated with second-stage juveniles (j2) of globodera rostochiensis pathotype rol. adult males emerged after 3-4 weeks and matings with females occurred. after 8 weeks gentle pressure on the eggs of maturing females released the j2 which were viable. because this technique enables the production of vigorously growing roots with numerous laterals, it may be suitable for obtaining a high yield of sterile potato cy ... | 1990 | 19287735 |
| fungal parasites of the potato cyst nematode globodera rostochiensis: isolation and reinfection. | fungal parasitism of eggs of the potato cyst nematode globodera rostochiensis was < 1, 3, and 17% at three sites in sweden. the fungi isolated most frequently from infected eggs were a septocylindrium-like fungus ( 19 %), exophiala spp. (17 %), and cylindrocarpon spp. (13 %). verticillium suchtasporium was isolated from infected eggs at a low frequency (4%). in laboratory experiments v. suchlasporium infected 93% of the eggs within cysts after 10 days on dilute corn meal agar. this species showe ... | 1990 | 19287764 |
| 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 ... | 1987 | 19290113 |
| movement of potato root diffusate through soil. | movement of potato root diffusate (prd) through soil was examined by using the hatch of eggs from globodera rostochiensis cysts as an indicator. porous bags containing cysts were placed at increasing distances and depths from potato roots, whose growth was restricted by nylon mesh. significantly greater hatch was observed up to 50 cm laterally away from potato roots, compared with hatch in fallow soil. eight weeks after plant emergence, we detected a concentration gradient of prd, as measured by ... | 1987 | 19290115 |
| decline of globodera rostochiensis as influenced by potato root diffusate movement and persistence in soil. | decline of globodera rostochiensis populations occurring naturally in soil and those added to potato hills and furrow centers in nylon bags was correlated with root weight of hudson, rosa, and katahdin potatoes at two locations in new york. cysts in bags were added to soil at planting and at 1, 3, 5, 7, and 9 weeks after emergence (ae). fallow decline required only 2-4 weeks in soil and did not increase with time. decline due to growing potatoes was greater in hills than in furrow centers, and r ... | 1987 | 19290126 |
| effects of host resistance on the fecundity of globodera rostochiensis. | the fecundity of globodera rostochiensis (ra) females that developed on resistant rosa and susceptible katahdin potato cultivars were compared. cysts collected from each cultivar were bulked, separated into four sizes (> 500 mum, 355-500 mum, 250-355 mum, and < 250 mum), and crushed to determine fecundity as measured by viable egg content (vec). fewer and generally smaller cysts developed on rosa than on katahdin. although cyst size significantly (p = 0.01) influenced vec, cyst age (8 or 13 week ... | 1988 | 19290192 |
| current research on the major nematode problems in japan. | among important nematode species occurring in japan, current research achievements with the following four nematodes are reviewed: 1) soybean cyst nematode (scn), heterodera glycines - breeding for resistance, race determination, association with cephalosporium gregatum in azuki bean disease, and isolation of hatching stimulant. 2) potato-cyst nematode (pcn), globodera rostochiensis - pathotype determination (ro 1), breeding for resistance, and control recommendations. 3) pinewood nematode (pwn) ... | 1988 | 19290201 |
| nematode problems affecting agriculture in the philippines. | nematodes are considered major pests on most economic crops in the philippines, particularly on banana, pineapple, citrus, tomato, ramie, and sugarcane. radopholus similis is the most destructive nematode on banana, while meloidogyne spp. are more serious on various vegetable crops such as tomato, okra, and celery and on fiber crops such as ramie. tylenchulus semipenetrans is a problem on citrus and rotylenchulus reniformis on pineapple and some legume crops. hirschmanniella oryzae and aphelench ... | 1988 | 19290204 |
| effects of host resistance on second-stage juveniles and adult males of globodera rostochiensis. | potato cultivars katahdin (susceptible) and rosa (resistant) were exposed to infective second-stage juveniles (j2) of globodera rostochiensis for varying periods of time, after which root systems were washed and plants were placed in hoagland's solution to assess j2 egression and male emergence. after transfer to liquid culture, many j2 egressed from both cultivars, but significantly more egressed from the resistant rosa than from katahdin. juveniles that egressed from rosa invaded a second host ... | 1988 | 19290220 |
| characterization and localization of saccharides on the head region of four populations of the potato cyst nematode globodera rostochiensis and g. pallida. | n-acetylglucosamine, galactose, n-acetylgalactosamine and mannose and (or) glucose were present on specimens of two populations of globodera rostochiensis and two of g. pallida representing four different pathotypes. individuals within the pathotypes varied in the amounts of some of the saccharides present. the pa population differed from the other populations in the presence on all individuals of n-acetylgalactosamine and the absence of extensive residues of mannose/glucose. tem studies showed ... | 1986 | 19294133 |
| management of globodera rostochiensis as influenced by nematode population densities and soil type. | the effects of aldicarb, oxamyl, 1,3-d, and plastic mulch (solarization) on soil population densities of the golden nematode (gn) globodera rostochiensis was assessed in field and microplot experiments with different soil types. oxamyl was evaluated in both soil and foliar treatments, whereas aldicarb, 1,3-d, and solarization were applied only to soil. soil applications of aldicarb and oxamyl resulted in reduced nematode populations after gn-susceptible potatoes in plots with initial population ... | 1986 | 19294143 |
| effects of initial nematode density on population dynamics of globodera rostochiensis on resistant and susceptible potatoes. | the influence of resistant and susceptible potato cultivars on globodera rostochiensis population density changes was studied at different nematode inoculum levels (pi) in the greenhouse and field. soil in which one susceptible and two resistant cultivars were grown and fallow soil in pots was infested with cysts to result in densities of 0.04-75 eggs/cm(3) soil. a resistant cultivar was grown in an infested field with pi of 0.7-16.7 eggs/cm(3) soil. pi was positively correlated with decline of ... | 1986 | 19294158 |
| globodera rostochiensis population density decline in relation to spatial distribution around resistant potato plants. | golden nematode, globodera rostochiensis (gn) population decline under resistant potatoes was related to cyst distance from plants 23 cm apart in rows 92 cm apart. gn decline, determined by sampling an infested field planted to the resistant cultivar 'yankee chipper', was 81.8% in cores 11.5 cm from plants within rows. decline was 27.4% at 23 cm from plants between rows and 36.6% at 46 cm. population decline of juveniles in cysts added to soil in bags was 90.3% for cysts 11.5 cm from plants with ... | 1986 | 19294159 |
| relationship between root growth of potato, root diffusate production, and hatching of globodera rostochiensis. | hatching response of globodera rostochiensis in potato root diffusate (prd) collected by soaking individual potato, solanum tuberosum, root systems in water for 2 hours was used to assess the relationship between root growth and prd production. resistant potato cultivars hudson and rosa were used as test plants. maximum hatch occurred in prd collected 3 weeks after plant emergence (ae) in the greenhouse, and declined after this time. hatch was positively correlated with increased root weight onl ... | 1986 | 19294195 |
| methods for reducing experimental variation in globodera rostochiensis. | | 1986 | 19294202 |
| root growth of susceptible and resistant potato cultivars and population dynamics of globodera rostochiensis in the field. | globodera rostochiensis population densities and potato root growth were measured in field plots of one susceptible and two resistant potato cultivars. root growth and nematode densities were estimated from soil samples taken at three depths between plants within the rows, three depths 22.5 cm from the rows, and at two depths midway between rows (furrows). four weeks after plant emergence (ae), nematode densities in the rows had declined 68% in plots of the susceptible cultivar and up to 75% in ... | 1986 | 19294219 |
| effects of host variety, photoperiod and chemical treatments on hatching of globodera rostochiensis. | golden nematode cysts were collected after they had completed one generation on an early, a mid-season, or a late-maturing potato variety ('superior,' 'katahdin,' and 'sebago,' respectively). the plants were grown in 8.5- or 16-h photoperiods and treated with gibberellic acid (ga) or xylocaine or both. when treated subsequently with potato root-diffusate few (13.3%) juveniles hatched from cysts collected from sehago, more (22.3%) from cysts collected from katahdin, and most (36.0%) from cysts co ... | 1982 | 19295697 |