Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| a rapid and efficient method for the screening of acid phosphatase 1 in young tomato seedlings, and for the identification of root-knot nematode species using miniaturized polyacrylamide gel electrophoresis. | a relatively rapid and highly sensitive miniaturized polyacrylamide gel electrophoresis technique is described for the analysis of certain isozymes from single cotyledons of tomato seedlings and from single females of the root-know nematode (meloidogyne spp.). homogenates from single tomato cotyledons (7, 14, 21, and 28 days old) were electrophoresed and stained for acid phosphatase 1 (aps 1) activity. cotyledons from plants of all the above age groups showed good aps 1 activity. nondestructive ... | 1992 | 1382970 |
| characterization of potentially functional 5s rrna-encoding genes within ribosomal dna repeats of the nematode meloidogyne arenaria. | in the plant-parasitic nematode meloidogyne arenaria, isolated rdna repeats show length heterogeneity, and are unusual in that they contain putative 5s ribosomal rna pseudogenes [vahidi et al., j. mol. evol. 27 (1988) 222-227]. potentially functional 5s rrna-encoding genes can also be identified in various rdna repeats, which appear to be tandemly organized in the genome. | 1991 | 1748312 |
| characterization of acetylcholinesterase molecular forms of the root-knot nematode, meloidogyne. | multiple molecular forms of acetylcholinesterase have been isolated and characterized from the root-knot nematodes meloidogyne arenaria and meloidogyne incognita. the forms of enzyme present in these 2 species are similar but not identical to those that occur in the free-living nematode caenorhabditis elegans. the 5 enzyme forms exhibit differential solubilities and can be classified into 3 classes, a, b, and c, based on substrate affinity, inhibitor and detergent sensitivity, and thermal inacti ... | 1991 | 1775164 |
| metabolism of plant sterols by nematodes. | parasitic nematodes do not biosynthesize sterols de novo and therefore possess a nutritional requirement for sterol, which must be obtained from their hosts. consequently, the metabolism of phytosterols by plant-parasitic nematodes is an important process with potential for selective exploitation. the sterol compositions of several species of plant-parasitic nematodes were determined by capillary gas chromatography-mass spectrometry and compared with the sterol compositions of their hosts. satur ... | 1991 | 1779708 |
| repeats and subrepeats in the intergenic spacer of rdna from the nematode meloidogyne arenaria. | ribosomal dna (rdna) repeats of the plant-parasitic nematode meloidogyne arenaria are heterogeneous in size and appear to contain 5s rrna gene sequences. moreover, in a reca+ bacterial host, plasmid clones of a 9 kb rdna repeat show deletion events within a 2 kb intergenic spacer (igs), between 28s and 5s dna sequences. these deletions appear to result from a reduction in the number of tandem 129 bp repeats in the igs. the loss of such repeats might explain how rdna length heterogeneity, observe ... | 1991 | 2062313 |
| unusual sequences, homologous to 5s rna, in ribosomal dna repeats of the nematode meloidogyne arenaria. | there are sequences homologous to 5s ribosomal rna in the ribosomal dna (rdna) repeats of the plant-parasitic nematode meloidogyne arenaria. this is surprising, because in all other higher eukaryotes studied to date, the genes for 5s rna are unlinked to and distinct from a tandem rdna repeat containing the genes for 18s, 5.8s, and 28s ribosomal rna. previously, only prokaryotes and certain "lower eukaryotes" (protozoa and fungi) had been found to have both the larger rrnas and 5s rrna represente ... | 1988 | 3138424 |
| low, but strongly structured mitochondrial dna diversity in root knot nematodes (meloidogyne). | root-knot nematodes (genus meloidogyne) have been the subject of recent and numerous studies of genetic variation because of the need to develop molecular diagnostics for the four globally distributed, parthenogenetic species that are significant agricultural pests. our analysis of meloidogyne mtdna improves on previous studies: (i) by examining restriction site polymorphism among a large number of isolates also characterized for standard morphological, host range and allozyme phenotypes; (ii) b ... | 1994 | 7911772 |
| identification of rapd, scar, and rflp markers tightly linked to nematode resistance genes introgressed from arachis cardenasii into arachis hypogaea. | two dominant genes conditioning resistance to the root-knot nematode meloidogyne arenaria were identified in a segregating f2 population derived from the cross of 4x (arachis hypogaea x arachis cardenasii)-ga 6 and pi 261942. mae is proposed as the designation for the dominant gene restricting egg number and mag is proposed as the designation for the dominant gene restricting galling. the high levels of resistance in ga 6 were introgressed from a. cardenasii and, therefore, a search to identify ... | 1996 | 8890516 |
| high-resolution dna fingerprinting of parthenogenetic root-knot nematodes using aflp analysis. | amplified fragment length polymorphism (aflp) analysis has been used to characterize 15 root-knot nematode populations belonging to the three parthenogenetic species meloidogyne arenaria, m. incognita and m. javanica. sixteen primer combinations were used to generate aflp patterns, with a total number of amplified fragments ranging from 872 to 1087, depending on the population tested. two kinds of polymorphic dna fragments could be distinguished: bands amplified in a single genotype, and bands p ... | 1998 | 9465419 |
| molecular cloning and characterisation of a venom allergen ag5-like cdna from meloidogyne incognita. | rna fingerprinting was used to identify rnas that were expressed in parasitic second-stage juveniles of meloidogyne incognita, but absent from or reduced in preparasitic second-stage juveniles. a cdna encoding a putative secretory protein was cloned from a m. incognita second-stage juvenile cdna library by probing with a 0.5kb fragment derived from fingerprinting that was more strongly expressed in parasitic second-stage juveniles. the cdna, named mi-msp-1, contained an open reading frame encodi ... | 2000 | 10675748 |
| virulence and molecular diversity of parthenogenetic root-knot nematodes, meloidogyne spp. | root-knot nematodes (rkn) are sedentary endoparasites causing severe damage to a wide variety of crops, including tomato. among them, the parthenogenetic species meloidogyne arenaria, m. incognita and m. javanica are of particular economic importance. the genetic diversity and relationships of 17 populations belonging to these three major species, either avirulent or virulent against the tomato mi resistance gene, were investigated in order to determine whether (a)virulence of the nematodes coul ... | 2000 | 10692014 |
| cloning and characterization of an extremely conserved satellite dna family from the root-knot nematode meloidogyne arenaria. | a new satellite dna family, named pmae, has been cloned from the genome of the phytoparasitic nematode, meloidogyne arenaria (nematoda: tylenchida). it is represented as tandemly repeated sequences with a monomeric unit of 172 bp. the monomers are present at approximately 15700 copies per haploid genome, and represent about 5.3% of the total genomic dna. twenty-seven independent monomers have been cloned and sequenced. the deduced consensus sequence is 70.9% a + t rich, with frequent stretches o ... | 2000 | 10791824 |
| immunolocalization of a putative cuticular collagen protein in several developmental stages of meloidogyne arenaria, globodera pallida and g. rostochiensis. | the monoclonal antibody iacr-ccnj.3d has previously been used to isolate a gene (gp-col-8) with strong similarity to cuticular collagen from a mixed stage globodera pallida cdna expression library. the antibody has also been shown to label specifically the amphidial canal of pre-parasitic second stage juveniles (j2) of several plant nematode species without any reactivity on the cuticular surface, indicating that this protein is either not present or is inaccessible on the cuticular surface. thi ... | 2002 | 12018190 |
| genetic diversity of root-knot nematodes from brazil and development of scar markers specific for the coffee-damaging species. | rapd markers were used to characterize the genetic diversity and relationships of root-knot nematodes (rkn) (meloidogyne spp.) in brazil. a high level of infraspecific polymorphism was detected in meloidogyne arenaria, meloidogyne exigua, and meloidogyne hapla compared with the other species tested. phylogenetic analyses showed that m. hapla and m. exigua are more closely related to one another than they are to the other species, and illustrated the early divergence of these meiotically reproduc ... | 2002 | 12416618 |
| the heat-stable root-knot nematode resistance gene mi-9 from lycopersicon peruvianum is localized on the short arm of chromosome 6. | the tomato gene mi-1 confers resistance to three species of root-knot nematodes, meloidogyne spp. however, the resistance mediated by mi-1 is inactive at soil temperatures above 28 degrees c. previously, we identified and mapped a novel heat-stable nematode resistance gene from the wild species lycopersicon peruvianum accession la2157 on to chromosome 6. here we report further characterization of this heat-stable resistance against three mi-1-avirulent biotypes of meloidogyne javanica, meloidogy ... | 2003 | 12589548 |
| protein variability in meloidogyne spp. (nematoda:meloidogynidae) revealed by two-dimensional gel electrophoresis and mass spectrometry. | total protein variation as revealed by two-dimensional electrophoresis (2d-e) was studied in 18 isolates from populations of meloidogyne arenaria (six isolates), meloidogyne incognita (10 isolates), and meloidogyne javanica (one isolate) plus an unclassified isolate. gels (80 x 60 x 0.75 mm) were silverstained and digitized in order to compare their protein patterns. optical density and position of protein patterns were measured using statistical cluster analysis and computer-assisted image anal ... | 2002 | 12645913 |
| polyploidy and parthenogenesis in the root-knot nematode meloidogyne arenaria. | 1963 | 14079604 | |
| location of independent root-knot nematode resistance genes in plum and peach. | prunus species express different ranges and levels of resistance to the root-knot nematodes (rkn) meloidogyne spp. in myrobalan plum ( prunus cerasifera), the dominant ma gene confers a high-level and wide-spectrum resistance to the predominant rkn, meloidogyne arenaria, meloidogyne incognita, meloidogyne javanica and the isolate meloidogyne sp. florida which overcomes the resistance of the amygdalus sources. in japanese plum ( prunus salicina), a similar wide-spectrum dominant resistance gene, ... | 2004 | 14569426 |
| evaluation of changes in the element content and biomass of invaded with meloidogyne arenaria tiny tim tomato plants under nh4vo3 treatment. | the parasite-host system meloidogyne arenaria--tiny tim tomato plants has been studied in order to investigate the influence of the process of invasion on the chemical composition and biomass of plants. the concentrations of seven chemical elements cu, zn, mg, k, na, mn and fe have been determined using aas in controls and invaded plants, and their changes have been evaluated under treatment with nh4vo3 in three different concentrations 0.01, 0.1 and 0.13 mg/100 ml h2o. the process of treatment ... | 2003 | 14711041 |
| nematicidal activity and chemical component of poria cocos. | poria cocos, a famous traditional chinese medicine, was found to have nematicidal activity in experiments searching for nematicidal fungi. the experiment showed it could kill 94.9% of the saprophytic nematode, panagrellus redivivue, 92.6% of the root-knot nematode, meloidogyne arenaria, and 93.5% of the pine nematode, bursaphelenchus xylophilus, on pda plate within 12 hours. according to the nematicidal activity, three new compounds, 2, 4, 6-triacetylenic octane diacid, 2, 4, 5, 6-tetrahydroxyhe ... | 2005 | 15765052 |
| resolving tylenchid evolutionary relationships through multiple gene analysis derived from est data. | sequence-based phylogenetic analyses typically are based on a small number of character sets and report gene trees which may not reflect the true species tree. we employed an est mining strategy to suppress such incongruencies, and recovered the most robust phylogeny for five species of plant-parasitic nematode (meloidogyne arenaria, m. chitwoodi, m. hapla, m. incognita, and m. javanica), three closely related tylenchid taxa (heterodera glycines, globodera pallida, and g. rostochiensis) and a di ... | 2005 | 15876542 |
| conserved and variable domains in satellite dnas of mitotic parthenogenetic root-knot nematode species. | two satellite dnas have been characterized in the mitotic parthenogenetic root-knot nematodes meloidogyne javanica and m. paranaensis, agriculturally important phytoparasitic species. the satellite repeat variants cloned from m. javanica could not be resolved from those described earlier in m. arenaria [castagnone-sereno, p., leroy, f., abad, p., 2000. cloning and characterization of an extremely conserved satellite dna family from the root-knot nematode meloidogyne arenaria. genome 43, 346-353] ... | 2005 | 16229973 |
| morphological variability and molecular phylogeny of the nematophagous fungus monacrosporium drechsleri. | an isolate of the nematode-trapping fungus monacrosporium drechsleri was collected from cultures of the root-knot nematode meloidogyne arenaria that had been maintained on tomato roots in greenhouse pots in beltsville, maryland. the plant-parasitic nematodes heterodera glycines, meloidogyne incognita and pratylenchus zeae and the free-living nematodes caenorhabditis elegans and panagrellus redivivus were placed on colonies of m. drechsleri grown in petri dishes to study ability of the isolate to ... | 2005 | 16396348 |
| isolation and characterization of another cdna encoding a chorismate mutase from the phytoparasitic nematode meloidogyne arenaria. | a new cdna, named ma-cm-2, encoding a chorismate mutase (cm), has been isolated from meloidogyne arenaria. the full-length cdna, carrying the trans-spliced sl1 leader sequence, was 753-bp long with an open reading frame of 576 bp. the deduced protein ma-cm-2 including amino-terminal signal peptide shows significant similarity to cms of meloidogyne incognita, meloidogyne javanica, and also bacteria. secondary structure prediction of ma-cm-2 indicates the presence of the three conserved alpha-heli ... | 2006 | 16458297 |
| observations on the suppression of root-knot nematode (meloidogyne arenaria) on tomato by incorporation of cyanobacterial powder (oscillatoria chlorina) into potting field soil. | experiments were carried out to investigate the nematicidal potential of a cyanobacterium, oscillatoria chlorina, against the root-knot nematode, meloidogyne arenaria on tomato plants grown in pots filled with 500 cm3 of field soil infested with 12-s stage juveniles (j2)/cm3 soil. incorporation of freeze-dried cyanobacterial powder into potted field soil at the rate of 0.2%, 0.4%, 0.6%, 0.8% and 1.0% (w/w) 5 days prior to tomato planting, reduced root galling, final population of m. arenaria and ... | 2007 | 16458501 |
| the ever-expanding neuropeptide gene families in the nematode caenorhabditis elegans. | neuropeptides act as chemical signals in the nervous system to modulate behaviour. with the ongoing est projects and dna sequence determination of different genomes, the identification of neuropeptide genes has been made easier. despite the relatively 'simple' repertoire of behaviours in the nematode caenorhabditis elegans, this worm contains a surprisingly large and diverse set of neuropeptide genes. at least 109 genes encoding over 250 potential neuropeptides have been identified in c. elegans ... | 2005 | 16569285 |
| preliminary study of the green algae chlorella (chlorella vulgaris) for control on the root-knot nematode (meloidogyne arenaria) in tomato plants and ectoparasite xiphinema indexin grape seedlings. | the alternative ecological methods require investigation of many organo-biological means for plant protection against dangerous root parasites such as root-knot nematode meloidogyne arenaria and some ectoparasites (xiphinema index). the bulgarian organic product - dry extract of green alga chlorella vulgaris ("the golden apple"-plamen barakov) is the latest product, which in comparative aspect gives the best results. series of laboratory and pot experiments are carried out with tomato (cv. bele ... | 2005 | 16628939 |
| root vs pod infection by root-knot nematodes on aflatoxin contamination of peanut. | aflatoxins are potent carcinogens produced by some aspergillus spp. infection of peanut (arachis hypogaea) by root-knot nematodes (meloidogyne arenaria) can lead to an increase in aflatoxin contamination of kernels when the plants are subjected to drought stress during pod maturation. it is not clear whether the increased aflatoxin contamination is primarily due to greater invasion of the galled pods by toxigenic aspergillus spp. or whether root galling is also involved. our objective was to det ... | 2007 | 18399500 |
| sensitive pcr detection of meloidogyne arenaria, m. incognita, and m. javanica extracted from soil. | we have developed a simple pcr assay protocol for detection of the root-knot nematode (rkn) species meloidogyne arenaria, m. incognita, and m. javanica extracted from soil. nematodes are extracted from soil using baermann funnels and centrifugal flotation. the nematode-containing fraction is then digested with proteinase k, and a pcr assay is carried out with primers specific for this group of rkn and with universal primers spanning the its of rrna genes. the presence of rkn j2 can be detected a ... | 2006 | 19259460 |
| virulence of meloidogyne spp. and induced resistance in grape rootstocks. | harmony grape rootstock displays resistance to several meloidogyne spp. but that resistance is not durable in commercial vineyard settings. a 2-year experiment in a microplot setting revealed host specificities of two virulent populations of meloidogyne arenaria and an avirulent population of meloidogyne incognita. in a subsequent split-root experiment, the avirulent nematode population was demonstrated to induce resistance to the virulent nematode population. to quantify the level of resistance ... | 2007 | 19259475 |
| comparison of methods for assessing resistance to meloidogyne arenaria in peanut. | use of resistant cultivars is a desirable approach to manage the peanut root-knot nematode (meloidogyne arenaria). to incorporate resistance into commercially acceptable cultivars requires reliable, efficient screening methods. to optimize the resistance screening protocol, a series of greenhouse tests were done using seven genotypes with three levels of resistance to m. arenaria. the three resistance levels could be separated based on gall indices as early as two weeks after inoculation (wai) u ... | 2007 | 19259486 |
| temporal formation and immunolocalization of an endospore surface epitope during pasteuria penetrans sporogenesis. | the synthesis and localization of an endospore surface epitope associated with the development of pasteuria penetrans was determined using a monoclonal antibody (mab) as a probe. nematodes, uninfected or infected with p. penetrans, were harvested at 12, 16, 24, and 38 days after inoculation (dai) and then examined to determine the developmental stage of the bacterium. vegetative growth of p. penetrans was observed only in infected nematodes harvested at 12 and 16 dai, whereas cells at different ... | 2003 | 19262762 |
| nucleotide substitution patterning within the meloidogyne rdna d3 region and its evolutionary implications. | evolutionary relationships based on nucleotide variation within the d3 26s rdna region were examined among acollection of seven meloidogyne hapla isolates and seven isolates of m. arenaria, m. incognita, and m. javanica. using d3a and d3b primers, a 350-bp region was pcr amplified from genomic dna and double-stranded nucleotide sequence obtained. phylogenetic analyses using three independent clustering methods all provided support for a division between the automictic m. hapla and the apomictic ... | 2003 | 19262771 |
| reproduction of meloidogyne spp. on resistant peanut genotypes from three breeding programs. | three described species of root-knot nematode parasitize peanut (arachis hypogaea): meloidogyne arenaria race 1 (ma), m. hapla (mh), and m. javanica (mj). peanut cultivars with broad resistance to meloidogyne spp. will be useful regardless of the species present in the field. the objective of this study was to determine whether peanut genotypes with resistance to m. arenaria originating from three different breeding programs were also resistant to m. hapla and m. javanica. the experiment used a ... | 2003 | 19262773 |
| meloidogyne javanica on peanut in florida. | a mixed population of meloidogyne arenaria race 1 and m. javanica race 3 is reported on peanut from a field in levy county, florida. confirmation of m. javanica on peanut is based on esterase and malate dehydrogenase isozyme patterns resolved on polyacrylamide slab gels following electrophoresis, and perineal patterns. up to 29% of 290 individual females collected from peanut roots in the field in autumn 2002 showed a typical esterase j3 phenotype for m. javanica. this is the third report of m. ... | 2003 | 19262776 |
| relationship between meloidogyne arenaria and aflatoxin contamination in peanut. | damaged and developing kernels of peanut (arachis hypogaea) are susceptible to colonization by fungi in the aspergillus flavus group which, under certain conditions, produces aflatoxins prior to harvest. our objective was to determine whether infection of peanut roots and pods by meloidogyne arenaria increases aflatoxin contamination of the kernels when peanut is subjected to drought stress. the experiment was a completely randomized 2-x-2 factorial with 6 replicates/treatment. the treatment fac ... | 2004 | 19262803 |
| life cycle, ultrastructure, and host specificity of the north american isolate of pasteuria that parasitizes the soybean cyst nematode, heterodera glycines. | light and transmission electron microscopy were used to investigate the life cycle and ultrastructure of an undescribed isolate of pasteuria that parasitizes the soybean cyst nematode, heterodera glycines. studies also were conducted to determine the host specificity of pasteuria. the endospores that attached to the cuticle of second-stage juveniles (j2) of h. glycines in soil did not germinate until the encumbered nematodes invaded soybean roots. thereafter, the bacterium developed and complete ... | 2004 | 19262804 |
| morphological and molecular characterization of meloidogyne mayaguensis isolates from florida. | the discovery of meloidogyne mayaguensis is confirmed in florida; this is the first report for the continental united states. meloidogyne mayaguensis is a virulent species that can reproduce on host cultivars bred for nematode resistance. the perineal patterns of m. mayaguensis isolates from florida show morphological variability and often are similar to m. incognita. useful morphological characters for the separation of m. mayaguensis from m. incognita from florida are the male stylet length va ... | 2004 | 19262811 |
| persistence and suppressiveness of pasteuria penetrans to meloidogyne arenaria race. | the long-term persistence and suppressiveness of pasteuria penetrans against meloidogyne arenaria race 1 were investigated in a formerly root-knot nematode suppressive site following 9 years of continuous cultivation of three treatments and 4 years of continuous peanut. the three treatments were two m. arenaria race 1 nonhost crops, bahiagrass (paspalum notatum cv. pensacola var. tifton 9), rhizomal peanut (arachis glabrata cv. florigraze), and weed fallow. two root-knot nematode susceptible wee ... | 2004 | 19262836 |
| distribution and downward movement of pasteuria penetrans in field soil. | endospores of pasteuria penetrans were evaluated for their vertical distribution in field soil and their downward movement through soil in the laboratory. in the field trial, the number of endospores attached to second-stage juveniles (j2) of meloidogyne arenaria race 1 varied greatly in different soil depths. there were higher percentages of j2 with endospores attached in former weed fallow plots during the first 3 years of growing peanut than in former bahiagrass and rhizomal peanut plots (p < ... | 2005 | 19262855 |
| a recessive gene for resistance to meloidogyne arenaria in interspecific arachis spp. hybrids. | a single dominant gene for resistance to meloidogyne arenaria was identified previously in two peanut cultivars, arachis hypogaea 'coan' and 'nematam'. the interspecific arachis hybrid txag-6 was the source of this resistance and the donor parent in a backcross breeding program to introgress resistance into cultivated peanut. to determine if other resistance genes were present in txag-6 and derived breeding populations from the third backcross generation (bc), f individuals were evaluated for th ... | 2005 | 19262858 |
| crop rotation and nematicides for management of mixed populations of meloidogyne spp. on tobacco. | the effects of crop rotation and the nematicides 1,3-dichloropropene (1,3-d), ethoprop, and fenamiphos on the relative frequency of meloidogyne incognita race 3, m. arenaria race 2, and m. javanica and tobacco yields on a sandy loam soil were determined. cropping sequences altered the species composition and population densities of meloidogyne spp. meloidogyne arenaria and m. incognita predominated when cotton, corn, sorghum, or rye-fallow preceded tobacco. meloidogyne javanica and m. arenaria p ... | 2001 | 19265896 |
| analysis of 1,3-dichloropropene for control of meloidogyne spp. in a tobacco pest management system. | 1,3-dichloropropene (1,3-d) and nonfumigant nematicides were evaluated for control of meloidogyne spp. and soil and foliar insects in a tobacco pest management system. in a field with a high meloidogyne spp. population density (root gall index 4.0 to 4.5 on a 0 to 10 scale in untreated controls), tobacco yields and crop values increased (482 kg/ha and $1,784/ha for 1, 3-d; 326 kg/ha and $1,206/ha for fenamiphos; 252 kg/ha and $933/ha for ethoprop) with nematicide application over an untreated co ... | 2001 | 19265897 |
| meloidogyne incognita and m. arenaria reproduction on dwarf hollies and lantana. | meloidogyne incognita and m. arenaria reproduction and host plant tolerance were assessed in field and greenhouse experiments on seven holly cultivars including ilex glabra 'shamrock', i. vomitoria 'schelling's dwarf', i. cornuta 'carissa', red holly hybrid (ilex little red), and i. crenata 'compacta', 'green luster', and 'helleri' as well as japanese boxwood (buxus microphylla) and two lantana cultivars (lantana camara 'miss huff' and 'new gold'). boxwood had the highest m. arenaria and m. inco ... | 2001 | 19265898 |
| developmental response of a resistance-breaking population of meloidogyne arenaria on vitis spp. | pre- and post-infection resistance mechanisms expressed by vitis rootstocks rs-9 and teleki 5c against second-stage juveniles (j2) of resistance-breaking populations of meloidogyne arenaria were observed and correlated with juvenile development and nematode reproduction. cabernet sauvignon grape was used as a susceptible control for comparison. similar numbers of j2 penetrated teleki 5c and cabernet sauvignon roots. root-tip necrosis, a hypersensitive reaction, occurred in both rootstocks but wa ... | 2002 | 19265904 |
| relationship between crop losses and initial population densities of meloidogyne arenaria in winter-grown oriental melon in korea. | to determine the economic threshold level, oriental melon (cucumis melo l. cv. geumssaragi-euncheon) grafted on shintozoa (cucurbita maxima x cu. moschata) was planted in plots (2 x 3 m) under a plastic film in february with a range of initial population densities (pi) of meloidogyne arenaria. the relationships of early, late, and total yield to pi measured in september and january were adequately described by both linear regression and the seinhorst damage model. initial nematode densities in s ... | 2002 | 19265907 |
| effects of switchgrass (panicum virgatum) rotations with peanut (arachis hypogaea l.) on nematode populations and soil microflora. | a 3-year field rotation study was conducted to assess the potential of switchgrass (panicum virgatum) to suppress root-knot nematodes (meloidogyne arenaria), southern blight (sclerotium rolfsii), and aflatoxigenic fungi (aspergillus sp.) in peanut (arachis hypogaea l.) and to assess shifts in microbial populations following crop rotation. switchgrass did not support populations of root-knot nematodes but supported high populations of nonparasitic nematodes. peanut with no nematicide applied and ... | 2002 | 19265915 |
| penetration and development of meloidogyne arenaria on two new grape rootstocks. | penetration, development, and reproduction of a virulent 'harmony' population of meloidogyne arenaria was studied on two nematode-resistant grape rootstocks 10-17a and 6-19b. 'cabernet sauvignon' was used as a susceptible control for comparison. plants were inoculated with 100 freshly hatched second-stage juveniles (j2) of m. arenaria. greater numbers of j2 penetrated roots of 'cabernet' than 10-17a, and none penetrated roots of 6-19b 4 days after inoculation (dai). at 7 dai, vermiform j2 advanc ... | 2002 | 19265923 |
| eggs of tylenchulus semipenetrans inhibit growth of phytophthora nicotianae and fusarium solani in vitro. | in previous greenhouse and laboratory studies, citrus seedlings infested with the citrus nematode tylenchulus semipenetrans and later inoculated with the fungus phylophthora nicotianae grew larger and contained less fungal protein in root tissues than plants infected by only the fungus, demonstrating antagonism of the nematode to the fungus. in this study, we determined whether eggs of the citrus nematode t. semipenetrans and root-knot nematode meloidogyne arenaria affected mycelial growth of p. ... | 2002 | 19265943 |
| host suitability of the olive cultivars arbequina and picual for plant-parasitic nematodes. | host suitability of olive cultivars arbequina and picual to several plant-parasitic nematodes was studied under controlled conditions. arbequina and picual were not suitable hosts for the root-lesion nematodes pratylenchus fallax, p. thornei, and zygotylenchus guevarai. however, the ring nematode mesocriconema xenoplax and the spiral nematodes helicotylenchus digonicus and h. pseudorobustus reproduced on both olive cultivars. the potential of meloidogyne arenaria race 2, m. incognita race 1, and ... | 2003 | 19265971 |
| mechanism of resistance to meloidogyne arenaria in the peanut cultivar coan. | resistance to meloidogyne arenaria in the peanut cultivar coan is inherited as a single, dominant gene. the mechanism of resistance to m. arenaria in coan was evaluated in three experiments. in the first experiment the number of second-stage juveniles (j2) of m. arenaria penetrating roots of the susceptible cultivar florunner was higher than the number of j2 penetrating roots of the resistant peanut cultivar coan (p < 0.05). in a second experiment it was determined that the root size and number ... | 2003 | 19265984 |
| pasteuria spp.: systematics and phylogeny of these bacterial parasites of phytopathogenic nematodes. | pasteuria spp. include endospore-forming bacterial pathogens of cladoceran crustaceans and plant-parasitic nematodes. propagation of these nematode pathogens requires attachment of soilborne endospores to nematode hosts, infection, growth, sporulation, and release of endospores to repeat the cycle of infection and propagation. the ability of these bacteria to suppress the levels of plant-parasitic nematodes in the field has made them particularly promising candidates for biocontrol of nematode d ... | 2003 | 19265995 |
| greenhouse studies on the effect of marigolds (tagetes spp.) on four meloidogyne species. | the effects of preplanted marigold on tomato root galling and multiplication of meloidogyne incognita, m. javanica, m. arenaria, and m. hapla were studied. marigold cultivars of tagetes patula, t. erecta, t. signata, and a tagetes hybrid all reduced galling and numbers of second-stage juveniles in subsequent tomato compared to the tomato-tomato control. all four meloidogyne spp. reproduced on t. signata 'tangerine gem'. several cultivars of t. patula and t. erecta suppressed galling and reproduc ... | 1999 | 19270876 |
| bahiagrass, corn, cotton rotations, and pesticides for managing nematodes, diseases, and insects on peanut. | florunner peanut was grown after 1 and 2 years of tifton 9 bahiagrass, corn, cotton, and continuous peanut as whole-plots. pesticide treatments aldicarb (3.4 kg a.i./ha), flutolanil (1.7 kg a.i./ha), aldicarb + flutolanil, and untreated (control) were sub-plots. numbers of meloidogyne arenaria second-stage juveniles in the soil and root-gall indices of peanut at harvest were consistently lower in plots treated with aldicarb and aldicarb + flutolanil than in flutolanil-treated and untreated plots ... | 1999 | 19270889 |
| genetics and mechanism of resistance to meloidogyne arenaria in peanut germplasm. | segregation of resistance to meloidogyne arenaria in six bcf peanut breeding populations was examined in greenhouse tests. chi-square analysis indicated that segregation of resistance was consistent with resistance being conditioned by a single gene in three breeding populations (tp259-3, tp262-3, and tp271-2), whereas two resistance genes may be present in the breeding populations tp259-2, tp263-2, and tp268-3. nematode development in clonally propagated lines of resistant individuals of tp262- ... | 1999 | 19270898 |
| 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 ... | 1999 | 19270925 |
| host suitability of potential cover crops for root-knot nematodes. | several potential cover crops were evaluated for their susceptibility to meloidogyne arenaria race 1, m. incognita race 1, and m. javanica in a series of five greenhouse experiments. no galls or egg masses were observed on roots of castor (ricinus communis), cowpea (vigna unguiculata cv. iron clay), crotalaria (crotalaria spectabilis), or american jointvetch (aeschynomene americana). occasional egg masses (rating </=1.0 on 0-5 scale) were observed on marigold (tagetes minuta) in one test with m. ... | 1999 | 19270926 |
| fosthiazate controls meloidogyne arenaria and m. incognita in flue-cured tobacco. | the nematicide fosthiazate was evaluated over a 3-year period for management of meloidogyne incognita race 3 (site 1) and m. arenaria race 2 (site 2) in flue-cured tobacco. fosthiazate was applied broadcast and incorporated at rates ranging from 22 to 88 g a.i./100 m(2), and compared with the nematicides fenamiphos (67 g a.i./100 m(2)), 1,3-d (56.1 l/ha, 670 ml/100-m row), and an untreated control. root-gall indices and leaf yields were averaged over the 3-year period. root galling was negativel ... | 1999 | 19270938 |
| population dynamics of meloidogyne incognita, m. arenaria,and other nematodes and crop yields in rotations of cotton, peanut, and wheat under minimum tillage. | wheat, cotton, and peanut were arranged in three cropping sequences to determine the effects of fenamiphos (6.7 kg a.i./ha) and cropping sequence on nematode population densities and crop yields under conservation tillage and irrigation for 6 years. the cropping sequences included a wheat winter cover crop each year and summer crops of cotton every year, peanut every year, or cotton rotated every other year with peanut. the population densities of meloidogyne spp. and helicotylenchus dihystera w ... | 2000 | 19270949 |
| extraction and purification of pasteuria spp. endospores. | pasteuria penetrans is an endospore-forming bacterial parasite of root-knot nematodes that has potential as a biological control agent. biochemical investigations of p. penetrans are limited because of difficulty in obtaining large quantities of endospores free of plant debris and contaminating microorganisms. our objective was to develop a technique for extraction and purification of p. penetrans endospores from root-knot nematodes. tomato roots infected with meloidogyne arenaria that was paras ... | 2000 | 19270952 |
| reproductive variability of field populations of meloidogyne spp. on grape rootstocks. | variability in penetration, development, and reproduction of two resistance-breaking field pathotypes (pt.) of meloidogyne arenaria, m. incognita, and a population of mixed meloidogyne spp. virulent to grape hosts were compared on two resistant vitis rootstocks 'freedom' and 'harmony' in separate tests. 'cabernet sauvignon' was included as a susceptible host to all four nematode populations. secondstage juveniles (j2) of the mixed population failed to penetrate freedom roots. by contrast, 6% of ... | 2000 | 19270976 |
| rate response of 1,3-dichloropropene for nematode control in spring squash in deep sand soils. | the soil fumigant 1,3-dichloropropene (1,3-d) formulated with chloropicrin is viewed as a likely alternative for replacing methyl bromide in florida when the latter is phased out in 2005. therefore, it behooves us to learn more about using 1,3-d in deep, sand soils. two trials were conducted on spring squash to determine the most effective rate of 1,3-d for the control of meloidogyne spp. rates tested included 0, 56, 84, 112, and 168 liters/ha of 1,3-d applied broadcast with conventional chisels ... | 2000 | 19271005 |
| resistance in selected corn hybrids to meloidogyne arenaria and m. incognita. | a total of 33 corn hybrids were evaluated in a series of greenhouse and field trials to determine if they differed in resistance to either meloidogyne incognita race 3 or m. arenaria race 1. reproduction of m. incognita race 3 and m. arenaria race 1 on the hybrids was also compared. reproduction of m. arenaria differed among corn hybrids after 58 to 65 days in greenhouse experiments; however, reproduction was similar among hybrids in the field experiment. no hybrids were consistently resistant t ... | 2000 | 19271019 |
| suppression mechanisms of meloidogyne arenaria race 1 by pasteuria penetrans. | the biological control of meloidogyne arenaria on peanut (arachis hypogaea) by pasteuria penetrans was evaluated using a six x six factorial experiment in field microplots over 2 years. the main factors were six inoculum levels of second-stage juveniles (j2) of m. arenaria race 1 (0, 40, 200, 1,000, 5,000, and 25,000 j2/microplot, except that the highest level was 20,000 j2/microplot in 1995) and six infestation levels of p. penetrans as percentages of j2 with endospores attached (0, 20, 40, 60, ... | 1997 | 19274127 |
| comparison of sequences from the ribosomal dna intergenic region of meloidogyne mayaguensis and other major tropical root-knot nematodes. | the unusual arrangement of the 5s ribosomal gene within the intergenic sequence (igs) of the ribosomal cistron, previously reported for meloidogyne arenaria, was also found in the ribosomal dna of two other economically important species of tropical root-knot nematodes, m, incognita and m. javanica. this arrangement also was found in m. hapla, which is important in temperate regions, and m. mayaguensis, a virulent species of concern in west africa. amplification of the region between the 5s and ... | 1997 | 19274129 |
| effects of temperature on resistance in phaseolus vulgaris genotypes and on development of meloidogyne species. | phaseolus vulgaris lines with heat-stable resistance to meloidogyne spp. may be needed to manage root-knot nematodes in tropical regions. resistance expression before and during the process of nematode penetration and development in resistant genotypes were studied at pre- and postinoculation temperatures of 24 degrees c and 24 degrees c, 24 degrees c and 28 degrees c, 28 degrees c and 24 degrees c, and 28 degrees c and 28 degrees c. resistance was effective at all temperature regimes examined, ... | 1997 | 19274137 |
| temperature-dependent development of pasteuria penetrans in meloidogyne arenaria. | pasteuria penetrans is a promising biological control agent of plant-parasitic nematodes. this study was conducted to determine effects of temperature on the bacterium's development in meloidogyne arenaria. developmental stages of p. penetrans were viewed with a compound microscope and verified with scanning electron microscopy within each nematode at 100 accumulated degree-day intervals by tracking accumulated degree-days at three temperatures (21, 28, and 35 degrees c). five predominant develo ... | 1997 | 19274154 |
| antibodies from chicken eggs as probes for antigens from pasteuria penetrans endospores. | the bacteria pasteuria spp. have been identified as among the most promising of several microbial organisms currently under investigation as biological control agents of plant-parasitic nematodes. as part of our goal to develop methods to discriminate isolates of pasteuria penetrans with different host preferences, we investigated the potential of developing antibody probes to identify endospores of different isolates of p. penetrans. polyclonal igy antibodies were raised in chickens against end ... | 1997 | 19274158 |
| differential response to root-knot nematodes in prunus species and correlative genetic implications. | responses of 17 prunus rootstocks or accessions (11 from the subgenus amygdalus and 6 from the subgenus prunophora) were evaluated against 11 isolates of meloidogyne spp. including one m. arenaria, four m. incognita, four m. javanica, one m. hispanica, and an unclassified population from florida. characterization of plant response to root-knot nematodes was based on a gall index rating. numbers of females and juveniles plus eggs in the roots were determined for 10 of the rootstocks evaluated aga ... | 1997 | 19274170 |
| damage functions for three meloidogyne species on arachis hypogaea in texas. | the yield response of florunner peanut to different initial population (pi) densities of meloidogyne arenaria, m. javanica, and an undescribed meloidogyne species (isolate 93-13a) was determined in microplots in 1995 and 1996. seven pi's (0, 0.5, 1, 5, 10, 50, and 100 eggs and j2/500 cm(3) soil) were used for each meloidogyne species in both years. the three species reproduced abundantly on florunner in both years. in 1995, mean reproduction differed among the three species; mean rf values were ... | 1997 | 19274184 |
| temperature effects on the attachment of pasteuria penetrans endospores to meloidogyne arenaria race 1. | pasteuria penetrans is a gram positive bacterium that prevents meloidogyne spp. from reproducing and diminishes their ability to penetrate roots. the attachment of the endospores to the cuticle of the nematodes is the first step in the life cycle of the bacterium and is essential for its reproduction. as a preliminary study to a field solarization test, the effects of temperature on the attachment of p. penetrans on meloidogyne arenaria race 1 were investigated. preexposing second-stage juvenile ... | 1997 | 19274192 |
| resistance of interspecific arachis breeding lines to meloidogyne javanica and an undescribed meloidogyne species. | resistance to a peanut-parasitic population of meloidogyne javanica and an undescribed meloidogyne sp. in peanut breeding lines selected for resistance to meloidogyne javanica was examined in greenhouse tests. the interspecific hybrid txag-7 was resistant to reproduction of meloidogyne javanica, m. javanica, and meloidogyne sp. an meloidogyne javanica-resistant selection from the second backcross (bc) of txag-7 to the susceptible cultivar florunner also was resistant to m. javanica but appeared ... | 1998 | 19274226 |
| resistance to root-knot, reniform, and soybean cyst nematodes in selected soybean breeding lines. | soybean breeding lines and reported sources of nematode resistance were evaluated in repeated greenhouse tests for resistance to north carolina populations of the soybean cyst nematode heterodera glycines, reniform nematode rotylenchulus reniformis, and the root-knot nematode species meloidogyne incognita, m. arenaria, and m. arenaria. lines from the soybean breeding program in missouri that had 'hartwig' soybean as a parent were the most resistant to races 1-4 of the soybean cyst nematode and t ... | 1998 | 19274243 |
| host status of herbaceous perennials to meloidogyne incognita and m. arenaria. | twenty-two different herbaceous perennials were studied for their reaction to separate inoculations of meloidogyne arenaria and m. incognita under greenhouse conditions. perennial taxa that did not develop root-galls following inoculation, and therefore are considered as nonhosts of both nematode species, included species and cultivars of aethionema, fragaria, phlox, and polygonum. echinacea, monarda, and patrinia developed only a few galls. root-galls developed on species and cultivars of achil ... | 1998 | 19274254 |
| effect of meloidogyne arenaria and mulch type on okra in microplot experiments. | the effects of perennial peanut (arachis glabrata) hay, an aged yard-waste compost (mainly woodchips), and a control treatment without amendment were determined on two population levels of root-knot (melaidogyne arenaria) nematode over three consecutive years in field microplots. okra (hibiscus esculentus, susceptible to the root-knot nematode) and a rye (secale cereale) cover crop (poor nematode host) were used in the summer and winter seasons, respectively. the organic amendment treatments aff ... | 1998 | 19274256 |
| effect of castor and velvetbean organic amendments on meloidogyne arenaria in greenhouse experiments. | effectiveness of castor (ricinus communis) and velvetbean (mucuna deeringiana) amendments was tested for suppression of the root-knot nematode (meloidogyne arenaria) and growth of okra (hibiscus esculentus) in three greenhouse experiments. regression analysis was used to relate nematode population data or plant growth responses to various rates (0, 1, 2, 4, or 8 g/560 cm(3) soil pot) of each amendment in separate experiments. in general, plant growth parameters responded positively to the amendm ... | 1998 | 19274257 |
| management of plant-parasitic nematodes on peanut with selected nematicides in north carolina. | field experiments were conducted to determine peanut growth and yield responses to selected fumigant and nonfumigant nemaficide treatments in 1988 and 1989. all treatments with the fumigant 1, 3-d significantly suppressed nematode reproduction (meloidogyne arenaria, m. hapla, and mesocriconema ornatum) and enhanced peanut yields over the other treatments in four tests in 1988. yield increases with the fumigant ranged from about 20% to 100% over the untreated control. test sites in 1989 had lower ... | 1998 | 19274260 |
| response of meloidogyne spp., heterodera glycines, and radopholus similis to tannic acid. | tannins, which are water-soluble polyphenols, are toxic to numerous fungi, bacteria, and yeasts. our objectives were to study the efficacy of tannic acid in control of meloidogyne arenaria on tomato and its effects on the behavior of m. arenaria, m. incognita, heterodera glycines, and radopholus similis. three concentrations of tannic acid, 0.1, 1.0, and 10 g/500 cm(3) of soil, were applied preplant (powder) and at-plant (powder and drench) into soil infested with m. arenaria. tannic acid at the ... | 1997 | 19274278 |
| suppression of meloidogyne arenaria race 1 by soil application of endospores of pasteuria penetrans. | the potential of pasteuria penetrans for suppressing meloidogyne arenaria race 1 on peanut (arachis hypogaea) was tested over a 2-year period in a field microplot experiment. endospores of p. penetrans were mass-produced on m. arenaria race 1 infecting tomato plants. endospores were inoculated in the first year only at rates of 0, 1,000, 3,000, 10,000, and 100,000 endospores/g of soil, respectively, into the top 20 cm of microplots that were previously infested with m. arenaria race 1. one peanu ... | 1996 | 19277131 |
| surface coat of meloidogyne incognita. | the nematode surface coat is defined as an extracuticular component on the outermost layer of the nematode body wall, visualized only by electron microscopy. surface coat proteins of meloidogyne incognita race 3 infective juveniles were characterized by electrophoresis and western blotting of extracts from radioiodine and biotin-labeled nematodes. extraction of labeled nematodes with cetyltrimethylammonium bromide yielded a principal protein band larger than 250 kda and, with water soluble bioti ... | 1996 | 19277137 |
| cellular responses of resistant and susceptible soybean genotypes infected with meloidogyne arenaria races 1 and 2. | the cellular responses induced by meloidogyne arenaria races 1 and 2 in three soybean genotypes, susceptible cns, resistant jackson, and resistant pi 200538, were examined by light microscopy 20 days after inoculation. differences in giant-cell development were greater between races than among the soybean genotypes. m. arenaria race 1 stimulated small, poorly formed giant-cells in contrast with m. arenaria race 2, which induced well-developed, thick-walled, multinucleate giant-cells. the number ... | 1996 | 19277138 |
| penetration and post-infectional development and reproduction of meloidogyne arenaria races 1 and 2 on susceptible and resistant soybean genotypes. | penetration, post-infectional development, reproduction, and fecundity of meloidogyne arenaria races 1 and 2 were studied on susceptible (cns), partially resistant (jackson), and highly resistant (pi 200538 and pi 230977) soybean genotypes in the greenhouse. the ability to locate and invade roots was similar between races, but more juveniles penetrated roots of susceptible cns than the resistant genotypes. at 10 days after inoculation, 56% and 99% to 100% of race 1 second-stage juveniles were ve ... | 1996 | 19277152 |
| role of nematodes, nematicides, and crop rotation on the productivity and quality of potato, sweet potato, peanut, and grain sorghum. | the objective of this experiment was to determine the effects of fenamiphos 15g and short-cycle potato (po)-sweet potato (sp) grown continuously and in rotation with peanut (pe)-grain sorghum (gs) on yield, crop quality, and mixed nematode population densities of meloidogyne arenaria, m. hapla, m. incognita, and mesocriconema ornatum. greater root-gall indices and damage by m. hapla and m. incognita occurred on potato than other crops. most crop yields were higher and root-gall indices lower fro ... | 1996 | 19277157 |
| responses of meloidogyne arenaria and m. incognita to green manures and supplemental urea in glasshouse culture. | the recent loss of many effective nematicides has led to renewed interest in alternative methods of nematode management. greenhouse experiments were conducted to determine the effects of rapeseed and velvetbean green manures, and supplemental urea, on the root-knot nematodes meloidogyne arenaria and m. incognita. green manures were incorporated with m. arenaria-infested soil using rates totaling 200,300, and 400 mg n/kg soil. squash plants grown in this soil were evaluated using a gall index and ... | 1996 | 19277190 |
| damage potential and reproduction of meloidogyne incognita race 3 and m. arenaria race 1 on kenaf. | the effects of meloidogyne incognita race 3 and m. arenaria race 1 on growth of kenaf cv. everglades 41 was determined under greenhouse conditions. seedlings of kenaf were inoculated with initial population densities (pi) of 0, 625, 1,250, 2,500, 5,000, and 10,000 eggs/plant and placed on greenhouse benches in a randomized complete block design. plant growth and nematode reproduction were assessed 6 and 12 weeks after inoculation. growth suppression of kenaf in response to increasing pi was obse ... | 1996 | 19277193 |
| intra- and interpopulation genome variation in meloidogyne arenaria. | the genetic heterogeneity of two m. arenaria race 2 populations (designated pelion and govan) was examined using rflp analysis of 12 clonal lines established from single egg masses (six distinct clonal lines from each population). these populations are essentially identical by traditional biochemical and race identification schemes; however, the govan population is more aggressive than the pelion population, producing larger galls and exhibiting greater reproductive capabilities on many soybean ... | 1995 | 19277274 |
| infection, reproduction potential, and root galling by root-knot nematode species and concomitant populations on peanut and tobacco. | single populations of meloidogyne arenaria races 1 (ma1) and 2 (ma2) and m. hapla (mh), and mixed populations of ma1 + ma2 and ma1 + mh with four inoculum levels of eggs were tested on peanut cv. 'florigiant' and m. incognita-resistant tobacco cv. 'mcnair 373' in a greenhouse experiment. root infection, female development, and reproduction of ma2 on peanut and ma1 on resistant tobacco were limited at 2 and 6 weeks. ma1, mh, and ma1 + mh on peanut had similar root infection (total parasitic forms ... | 1995 | 19277277 |
| effects of peanut-tobacco rotations on population dynamics of meloidogyne arenaria in mixed race populations. | a 3-year microplot study was initiated to characterize the population dynamics, reproduction potential, and survivorship of single or mixed populations of meloidogyne arenaria race 1 (ma1) and race 2 (ma2), as affected by crop rotations of peanut 'florigiant' and m. incognita races 1 and 3-resistant 'mcnair 373' and susceptible 'coker 371-gold' tobacco. infection, reproduction, and root damage by ma2 on peanut and by ma1 on resistant tobacco were limited in the first year. infection, reproductio ... | 1995 | 19277278 |
| effects of peanut genotypes on meloidogyne species interactions. | a 3-year microplot study was conducted to characterize the interaction between meloidogyne arenaria race 1 (ma1) and m. hapla (mh), as affected by the five peanut genotypes: florigiant, nc 7, nc 6, nc ac 18416, and nc ac 18016. the interactive effects on infection (total parasitic forms per root unit) and reproduction potentials of each nematode species and crop damage were determined. as a single population, ma1 had greater infection capacity and caused more crop damage than did mh, but both sp ... | 1995 | 19277279 |
| temporal efficacy of selected nematicides on meloidogyne species on tobacco. | aldicarb, ethoprop, and fenamiphos were evaluated for their efficacy in controlling various species of root-knot nematodes on flue-cured tobacco and for their residual activity, as determined through periodic sampling and bioassays of soil taken from field plots. field experiments were conducted at five locations over 2 years with flue-cured tobacco. soil in plots treated with nematicides were formed into high, wide beds before transplanting with 'coker 371-gold' or 'k 326' tobacco. residual con ... | 1995 | 19277289 |
| responses of some common cruciferae to root-knot nematodes. | ten cultivated plants of the family cruciferae were evaluated for susceptibility to meloidogyne arenaria race 1, m. incognita races 1 and 3, and m. javanica in a series of four separate greenhouse tests. after 62-64 days, or 1,032-1,072 degree days (10 c base), several of the crops evaluated showed moderate to severe levels of galling (> 3.0 on 0-5 scale) and moderate numbers of egg masses (>2.0 on 0-5 scale) in response to each of the nematode species and races. among the plants tested, collard ... | 1995 | 19277321 |
| reproduction of meloidogyne arenaria, m. incognita, and m. javanica on sesame. | reproduction of meloidogyne arenaria race 1, m. ineognita races 1 and 3, and m. javanica on 10 cultivars of sesame (sesame indicum) was examined in greenhouse tests. sesame cultivars were also evaluated in a field infested with m. arenaria. sesame was a poor host for m. incognita races 1 and 3 as no sesame genotype supported more than 70 eggs/g root. reproduction of m. arenaria race 1 on sesame varied from 20 eggs/g roots for cultivar sesaco 7cb to 1,570 eggs/g roots for sesaco 119 in the greenh ... | 1995 | 19277331 |
| effect of cutting age on the resistance of prunus cerasifera (myrobalan plum) to meloidogyne arenaria. | the response of softwood cuttings of myrobalan plum infested after 50 and 105 days with 3,000 second-stage juveniles (j2) of meloidogyne arenaria was compared to 15-month-old hardwood cuttings in 13 genotypes ranging from highly resistant to susceptible. gall index and number of galls were recorded 30 days after infestation. fifty-day-old cuttings rooted in perlite developed many rootlets, but had only incipient galls after infestation. in sand, rooting of 50-day-old cuttings not treated with in ... | 1995 | 19277333 |
| quantification of endospore concentrations of pasteuria penetrans in tomato root material. | six methods for quantification of the endospore concentrations of pasteuria penetrans from tomato roots are described. mortar disruption and machine disruption methods gave the highest estimations (endospores per gram of root material) of 83.7 and 79.0 million, respectively. these methods were significantly superior to incubation bioassay (47.7 million), enzymatic disruption (32.1 million), and enzymatic disruption + flotation (25.8 million) methods. a centrifugation bioassay method gave the low ... | 1996 | 19277345 |
| additive effects of meloidogyne arenaria and sclerotinin rolfsii on peanut. | field observations have suggested that infection of peanut by meloidogyne arenaria increases the incidence of southern blight caused by sclerotium rolfsii. three factorial experiments in microplots were conducted to determine if interactions between m. arenaria and s. rolfsii influenced final nematode population densities, incidence of southern blight, or pod yield. treatments included four or five initial population densities of m. arenaria and three inoculum rates of s. rolfsii. final nematode ... | 1996 | 19277351 |
| a polymerase chain reaction method for identification of five major meloidogyne species. | a polymerase chain reaction (pcr) method for discriminating meloidogyne incognita, m. arenaria, m. javanica, m. hapla, and m. chitwoodi was developed. single juveniles were ruptured in a drop of water and added directly to a pcr reaction mixture in a microcentrifuge tube. primer annealing sites were located in the 3' portion of the mitochondrial gene coding for cytochrome oxidase subunit ii and in the 16s rrna gene. following pcr amplification, fragments of three sizes were detected. the m. inco ... | 1993 | 19279734 |
| penetration rates by second-stage juveniles of meloidogyne spp. and heterodera glycines into soybean roots. | the rates of soybean root penetration by freshly hatched second-stage juveniles (j2) of meloidogyne arenaria, m. hapla, m. incognita, m. javanica, and heterodera glycines races 1 and 5 were examined over a period of 1 to 240 hours. heterodera glycines entered roots more quickly than meloidogyne spp. penetration by most nematodes was accomplished within 48 hours. the increases in penetration after 48 hours were insufficient to warrant further assessments. penetration of j2 into roots of soybean s ... | 1993 | 19279739 |
| effects of chicken-excrement amendments on meloidogyne arenaria. | the effects of chicken litter on meloidogyne arenaria in tomato plants cv. rutgers were determined in the greenhouse. tomato seedlings were transplanted into a sandy soil amended with five rates of chicken litter and inoculated with 2,000 m. arenaria eggs. after 10 days, total numbers of nematodes in the roots decreased with increasing rates of chicken litter. after 46 days, egg numbers also decreased with increasing litter rates. in another experiment, soil was amended with two litter types, n- ... | 1993 | 19279745 |
| morphological comparison of seven hypotriploid populations of meloidogyne arenaria with the typical triploid populations. | a morphological comparison of seven hypotriploid populations of meloidogyne arenaria was made to clarify their taxonomic status, using light and scanning electron microscopy. all populations differed from each other and from the typical triploid m. arenaria by certain features. differences were not regarded as sufficient to justify recognition of the variants as distinct species. morphological divergence of populations from the typical m. arenaria was gradual. the most useful characters were sty ... | 1993 | 19279750 |
| morphometric evaluation of hypotriploid and triploid populations of meloidogyne arenaria. | a morphometric comparison of seven hypotriploid populations with five pooled triploid populations of meloidogyne arenaria was made using standard descriptive statistics, stepwise discriminant analysis (sda), and cluster analysis. six morphometric characters of females, 14 of second-stage juveniles (j2), and 18 of males were measured for each population. useful differentiating characters included: body length in j2; stylet length in females and j2; stylet-knob dimensions in females and males; dor ... | 1993 | 19279751 |