| a basic serine protease from paecilomyces lilacinus with biological activity against meloidogyne hapla eggs. | scanning electron micrographs of the nematode-egg-parasitic fungus paecilomyces lilacinus infecting eggs of the root-knot nematode meloidogyne spp. suggested the involvement of lytic enzymes. when grown on a liquid mineral salts medium, supplemented with different substrates as the sole n- and c-source, the fungus produced an extracellular protease. colloidal chitin, vitellin and intact eggs of the root-knot nematode meloidogyne hapla induced proteolytic activity that was repressed by glucose. t ... | 1995 | 7773385 |
| evolution of the at-rich mitochondrial dna of the root knot nematode, meloidogyne hapla. | mitochondrial dna of the root knot nematode meloidogyne hapla was investigated for intraspecific diversity and divergence from other parthenogenetic root knot nematodes. a 1,900-bp fragment containing coii, trnahis, 16s rrna, nd3 and cyt b genes has been cloned and sequenced from one individual and an 1,188-bp region within this region was sequenced from four other australian isolates. m. hapla mtdna is more than 80% at-rich, like other meloidogyne spp. nucleotide diversity within m. hapla is so ... | 1997 | 9000752 |
| a new alui satellite dna in the root-knot nematode meloidogyne fallax: relationships with satellites from the sympatric species m. hapla and m. chitwoodi. | a highly abundant satellite dna comprising 20% of the meloidogyne fallax (nematoda, tylenchida) genome was cloned and sequenced. the satellite monomer is 173 bp long and has a high a + t content of 72.3%, with frequent runs of a's and t's. the sequence variability of the monomers is 2.7%, mainly due to random distribution of single-point mutations. a search for evidence of internal repeated subunits in the monomer sequence revealed a 6-bp motif (aaattt) for which five degenerated repeats, differ ... | 1998 | 9729876 |
| 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 |
| 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 |
| internalization of escherichia coli o157:h7 following biological and mechanical disruption of growing spinach plants. | the internalization and persistence of a bioluminescent escherichia coli o157:h7 ph1 was investigated in growing spinach plants that had been either biologically or mechanically damaged. in control (undamaged) plants cultivated in soil microcosms inoculated with e. coli o157:h7 phl, the bacterium was recovered from surface-sterilized root tissue but not from leaves. mechanical disruption of the seminal root and root hairs of the plants did not result in the internalization of the pathogen into t ... | 2005 | 16355819 |
| [diversity of actinomycetes associated with root-knot nematode and their potential for nematode control]. | twenty actinomycetes were isolated from root-knot nematode eggs and females collected from 11 plant root samples infested by meloidogyne spp.. the isolates were assigned to the genera streptomyces, nocardia and pseudonocardia respectively, based on analysis of morphological characteristics, cell-wall daps and 16s rrna gene sequences. 80% of them were streptomycetes. biocontrol potential of the isolates against meloidogyne hapla was evaluated in liquid culture in vitro. the average percentages of ... | 2006 | 17037062 |
| morphological and molecular characteristics of a new species of pasteuria parasitic on meloidogyne ardenensis. | a species of the hyper-parasitic bacterium pasteuria was isolated from the root-knot nematode meloidogyne ardenensis infecting the roots of ash (fraxinus excelsior). it is morphologically different from some other pasteuria pathogens of nematodes in that the spores lack a basal ring on the ventral side of the spore and have a unique clumping nature. transmission electron microscopy (tem) showed that the clumps of spores are not random aggregates but result from the disintegration of the suicide ... | 2007 | 17399736 |
| 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 |
| inter- and intra-specific cuticle variation between amphimictic and parthenogenetic species of root-knot nematode (meloidogyne spp.) as revealed by a bacterial parasite (pasteuria penetrans). | specific host-parasite interactions exist between species and strains of plant parasitic root-knot nematodes and the gram-positive bacterial hyperparasite pasteuria penetrans. this bacterium produces endospores that adhere to the cuticle of migrating juveniles, germinate and colonise the developing female within roots. endospore attachment of p. penetrans populations to second-stage juveniles of the root-knot nematode species meloidogyne incognita and meloidogyne hapla showed there were interact ... | 2008 | 18171577 |
| a novel negative regulatory factor for nematicidal cry protein gene expression in bacillus thuringiensis. | a 3-kb hindiii fragment bearing the cry6aa2 gene and the adjacent and intergenic regions was cloned from bacillus thuringiensis strain ybt-1518. two open reading frames (orfs), namely, orf1 (termed cry6aa2) and orf2 that were separated by an inverted-repeat sequence were identified. orf1 encoded a 54-kda protein that exhibited high toxicity to the plant-parasitic nematode meloidogyne hapla. the orf2 expression product was not detected by sds-page, but its mrna was detected by rt-pcr. the orf2 co ... | 2008 | 18600043 |
| new strategy for isolating novel nematicidal crystal protein genes from bacillus thuringiensis strain ybt-1518. | we have developed a strategy for isolating cry genes from bacillus thuringiensis. the key steps are the construction of a dna library in an acrystalliferous b. thuringiensis host strain and screening for the formation of crystal through optical microscopy observation and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (sds-page) analyses. by this method, three cry genes--cry55aa1, cry6aa2, and cry5ba2--were cloned from rice-shaped crystals, producing b. thuringiensis ybt-1518, which co ... | 2008 | 18820056 |
| effect of crop rotation on meloidogyne spp. and pratylenchus spp. populations in strawberry fields in taiwan. | changes in population levels of meloidogyne hapla, m. incognita, pratylenchus coffeae, and p. penetrans were studied in 12 strawberry fields in the dahu region of taiwan. ten potential rotation crops and two cultural practices were evaluated for their effect on nematode populations and influence on strawberry yield. rotation with rice or taro and the cultural practice of flooding and bare fallowing for four months were found to reduce nematode soil populations to two or fewer nematodes per 100 m ... | 2006 | 19259538 |
| effect of compost and manure soil amendments on nematodes and on yields of potato and barley: a 7-year study. | a 7-year study located in prince edward island, canada, examined the influence of compost and manure on crop yield and nematode populations. the compost used in this study consisted of cull waste potatoes, sawdust, and beef manure in a 3:3:1 ratio, respectively. no plant-parasitic nematodes were detected in samples collected from windrow compost piles at 5- and 30-cm depths prior to application on field plots. low population densities of bacterial-feeding nematodes were recovered from compost wi ... | 2003 | 19262763 |
| seasonal populations of pratylenchus penetrans and meloidogyne hapla in strawberry roots. | strawberry roots were sampled through the year to determine the populations and distribution of pratylenchus penetrans and meloidogyne hapla. three strawberry root types were sampled-structural roots; feeder roots without secondary tissues; and suberized, black perennial roots. both lesion and root-knot nematodes primarily infected feeder roots from structural roots or healthy perennial roots. few nematodes were recovered from soil, diseased roots, or suberized roots. lesion nematode recovery wa ... | 2002 | 19265965 |
| phenotypic and molecular analysis of a pasteuria strain parasitic to the sting nematode. | pasteuria strain s-1 was found to parasitize the sting nematode belonolaimus longicaudatus. s-1 spores attached to several strains of b. longicaudatus from different geographical locations within the united states. however, they did not adhere to any of the following species: heterodera schachtii, longidorus africanus, meloidogyne hapla, m. incognita, m. javanica, pratylenchus brachyurus, p. scribneri, p. neglectus, p. penetrans, p. thornei, p. vulnus, and xiphinema spp. the 16s rrna genes from ... | 2001 | 19266005 |
| 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 |
| 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 |
| plant-parasitic nematodes associated with grapevines, vitis vinifera, in oregon vineyards. | a survey of vineyards in western oregon was conducted in 1994 and 1995 to determine the association of plant-parasitic nematodes with vine health. seventy vineyards in four regions of western oregon (16 to 21 vineyards per region) were sampled. the regions were the northern, middle, and southern willamette valley, and southern oregon. vineyards were selected and partitioned into blocks by variety, age of planting, crop history, and soil characteristics. mesocriconema xenoplax, xiphinema american ... | 1999 | 19270927 |
| influence of rotation crops on the strawberry pathogens pratylenchus penetrans, meloidogyne hapla, and rhizoctonia fragariae. | field microplot, small plot, and greenhouse experiments were conducted to determine the effects of rotation crops on pratylenchus penetrans, meloidogyne hapla, and rhizoctonia fragariae populations. extraction of p. penetrans from roots and soil in microplots and field plots planted to rotation crops was highest for garry oat, lowest for triple s sorgho-sudangrass and saia oat, and intermediate for strawberry, buckwheat, and canola. isolation of r. fragariae from bait roots was highest for straw ... | 1999 | 19270931 |
| suppression of meloidogyne hapla and its damage to lettuce grown in a mineral soil amended with chitin and biocontrol organisms. | chitin was used as soil amendment in fiberglass field microplots, alone or with one or a combination of two to three species of hirsutella rhossiliensis, paecilomyces marquandii, verticillium chlamydosporium, bacillus thuringiensis, and streptomyces costaricanus. sudangrass and rapeseed were planted as cover crops and incorporated into soil as green manure amendments. chitin amendment alone increased the marketable yield of lettuce in 1995 and reduced root-galling ratings and the reproduction of ... | 1999 | 19270942 |
| efficacy of bacillus thuringiensis, paecilomyces marquandii,and streptomyces costaricanus with and without organic amendments against meloidogyne hapla infecting lettuce. | chitin, wheat mash, or brewery compost were incorporated into unfumigated and methyl bromide-fumigated organic soils placed in microplots formed from cylindrical drainage tiles (0.25 m-diam. clay tile). after 3 weeks, meloidogyne hapla and cell or spore suspensions of bacillus thuringiensis, paecilomyces marquandii, and streptomyces costaricanus were individually added to the soils of designated microplots. a b. thuringiensis + s. costaricanus combination was also tested. lettuce seedlings, cv. ... | 2000 | 19270951 |
| hirsutella rhossiliensisand verticillium chlamydosporium as biocontrol agents of the root-knot nematode meloidogyne hapla on lettuce. | hirsutella rhossiliensis and verticillium chlamydosporium infected second-stage juveniles (j2) and eggs of meloidogyne hapla, respectively, in petri dishes and in organic soil in pots planted to lettuce in the greenhouse. in vitro, h. rhossiliensis produced 78 to 124 spores/infected j2 of m. hapla. the number of j2 in roots of lettuce seedlings decreased exponentially with increasing numbers of vegetative colonies of h. rhossiliensis in the soil. at an infestation of 8 m. hapla eggs/cm(3) soil, ... | 2000 | 19270953 |
| trichoderma harzianum endochitinase does not provide resistance to meloidogyne hapla in transgenic tobacco. | eggs of meloidogyne hapla contain chitin, a substrate for chitinase. our goal was to determine if endochitinase from the biocontrol fungus t. harzianum expressed in transgenic tobacco increases resistance to this nematode. endochitinase-transgenic t tobacco seedlings expressing increased endochitinase activity in leaves (11 to 125 times over control) and roots (2 to 15 times over control) were transferred to quartz sand:loam soil mix (4:1 ratio) and inoculated with 5,000 m. hapla eggs/pot. tomat ... | 2000 | 19270979 |
| host-parasite relationships of meloidogyne trifoliophila isolates from new zealand. | root-infecting nematodes are commonly found on white clover in new zealand pasture where they reduce yield, nitrogen fixation, and persistence. the dominant root-knot nematode on white clover in new zealand is confirmed in this study as meloidogyne trifoliophila by isozyme phenotype comparison with the type population from tennessee. results from a host differential test differed in the host ranges of m. trifoliophila and m. hapla from new zealand locations, with m. trifoliophila failing to repr ... | 1997 | 19274134 |
| 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 |
| evaluation of 15 trifolium spp. and of medicago sativa as hosts of four meloidogyne spp. found in new zealand. | the predominant root-knot nematode in new zealand pastures is meloidogyne trifoliophila, identified until recently as m. hapla. clarification was needed on the host range of these two species on legumes found in new zealand pastures and on clover species closely related to trifolium repens. in a greenhouse test, 15 trifolium spp. and medicago sativa were inoculated with eggs of m. trifoliophila, m. hapla, m. incognita, or m. javanica. all legumes tested were hosts to some degree to each of the r ... | 1997 | 19274267 |
| differential sensitivity of meloidogyne spp. and heterodera glycines to selected nematicides. | differential sensitivity of meloidogyne arenaria, m. hapla, m. incognita, m. javanica, and heterodera glycines races 1 and 5 to the nonfumigant nematicides aldicarb, ethoprop, and fenamiphos was evaluated using a 48-hour root-penetration bioassay. generally, h. glycines was more tolerant of the nematicides, especially ethoprop, than were the meloidogyne species. among meloidogyne species, m. incognita was most sensitive to aldicarb and fenamiphos, but its reaction to ethoprop was similar to the ... | 1993 | 19279834 |
| reproduction of plant-parasitic nematodes on winter rapeseed (brassica napus ssp. oleiferas). | the reproduction of isolates of five plant-parasitic nematode species on the winter rapeseed cultivars bridger, gorzanski, h-47, lindora, and viking was evaluated. each cultivar was a good host for helicotylenchus pseudorobustus, meloidogyne hapla, and m. incognita, all rapeseed cultivars were poor hosts for pratylenchus scribneri, in comparison with a susceptible reference host. heterodera glycines females rarely developed on any cultivar, but low numbers of juveniles invaded roots and males oc ... | 1993 | 19279854 |
| predisposition of broadleaf tobacco to fusarium wilt by early infection with globodera tabacum tabacum or meloidogyne hapla. | in greenhouse experiments, broadleaf tobacco plants were inoculated with tobacco cyst (globodera tabacum tabacum) or root-knot (meloidogyne hapla) nematodes 3, 2, or 1 week before or at the same time as fusarium oxysporum. plants infected with nematodes prior to fungal inoculation had greater fusarium wilt incidence and severity than those simultaneously inoculated. g. t. tabacum increased wilt incidence and severity more than did m. hapla. mechanical root wounding within 1 week of f. oxysporum ... | 1992 | 19283018 |
| efficacy of oxamyl coated on alfalfa seed with a polymer sticker in pratylenchus and meloidogyne infested soils. | a polymer sticker was used as a coating in which oxamyl was applied to seeds of alfalfa cultivar saranac for the control of pratylenchus penetrans and meloidogyne hapla. the sticker, diluted 1:1 (sticker:water) to 1:5, delayed seedling emergence during the first 4 days after planting. by day 13, however, emergence from all sticker treatments was comparable to the control. shoot growth of seedlings at day 21 was less than that of the control only from seeds coated with a 1:1 dilution; root growth ... | 1989 | 19287603 |
| host range and ecology of isolates of pasteuria spp. from the southeastern united states. | isolates of pasteuria penetrans were evaluated for ecological characteristics that are important in determining their potential as biological control agents. isolate p-20 survived without loss of its ability to attach to its host nematode in dry, moist, and wet soil and in soil wetted and dried repeatedly for 6 weeks. some spores moved 6.4 cm (the maximum distance tested) downward in soil within 3 days with percolating water. the isolates varied greatly in their attachment to different nematode ... | 1990 | 19287753 |
| plant-parasitic nematodes and fungi associated with root rot of peas on prince edward island. | eight commercial pea fields on prince edward island were sampled in june and july over a 2-year period (1986-87) to determine soil population densities and the incidence of nematodes and fungi associated with root rot of peas. root lesion nematodes (pratylenchus spp.) were the dominant endoparasitic nematodes recovered from roots and soil. low populations of the northern root-knot nematode (meloidogyne hapla) were also present. tylenchorhynchus spp. and paratylenchus spp. were recovered frequent ... | 1990 | 19287779 |
| plant-parasitic nematodes in maine agricultural soils. | in a survey of plant-parasitic nematodes associated with agricultural crops in nine maine counties, 744 soil samples from 26 potential host plants were analyzed between november 1987 and january 1989. the most commonly encountered nematode genus was pratylenchus, occurring in 85% of the samples from most crops, except blueberries and onions. pratylenchus penetrans and p. crenatus were found commonly as species mixtures, with p. penetrans composing 40-80% of the mixture. meloidogyne hapla was enc ... | 1990 | 19287791 |
| evaluation of cultivars, experimental lines and plant introduction collection of sainfoin for resistance to meloidogyne hapla chitwood. | stands of several cultivars and experimental lines of sainfoin (onobrychis viciifolia) were severely reduced (92% average loss) in a field naturally infested with meloidogyne hapla. stands of two alfalfa cultivars included in the test were unaffected. in studies conducted in the greenhouse with plants inoculated at the time of seeding, average mortality was 55% for sainfoin entries and 7% for ladak alfalfa. little mortality occurred when plants were inoculated after establishment. three months a ... | 1987 | 19290103 |
| control of pratylenchus penetrans and meloidogyne hapla and yield response of alfalfa due to oxamyl seed treatments. | alfalfa (medicago sativa l. cv. saranac) seed were soaked for 20 minutes in water, acetone, or methanol containing 10 or 50 mg/ml of oxamyl (vydate l) or coated with a 2% aqueous cellulose solution containing the same amounts of oxamyl. seed were analyzed for oxamyl by hplc immediately after treatment and after 9 and 26 months of storage. oxamyl content of alfalfa seed did not decline after 26 months of storage. the effects of seed treatment on growth of alfalfa and nematode control were examine ... | 1987 | 19290170 |
| differential reaction of alfalfa cultivars to meloidogyne hapla and m. chitwoodi populations. | meloidogyne hapla reproduced and suppressed growth (p < 0.05) of susceptible lahontan and moapa alfalfa at 15, 20, and 25 c. at 30 c, resistant nevada syn xx lost resistance to m. hapla. m. hapla invaded and reproduced on rhizobium meliloti nodules of lahontan and moapa, inducing giant cell formation and structural disorder of vascular bundles of nodules without disrupting bacteroids. at 15, 20, and 25 c a m. chitwoodi population from utah reproduced on lahontan, moapa, and nevada syn xx alfalfa ... | 1986 | 19294189 |
| interactions among selected endoparasitic nematodes and three pseudomonads on alfalfa. | meloidogyne hapla, pratylenchus penetrans, and helicotylenchus dihystera, reduced the growth of 'saranac ar alfalfa seedlings when applied at concentrations of 50 nematodes per plant. all except p. penetrans reduced seedling growth when applied at 25 per seedling. m. hapla reduced growth when applied at 12 per seedling. nematodes interacted with three pseudomonads to produce greater growth reductions than were obtained with single pathogens, suggesting synergistic relationships. ditylenchus dips ... | 1982 | 19295682 |
| histopathology of selected cultivars of tobacco infected with meloidogyne species. | rates of nematode penetration and the histopathology of root infections in fluecured tobacco cultivars 'mcnair-944,' 'speight g-28,' and 'nc-89' with either meloidogyne arenaria, m. incognita, m. hapla, or m. javanica were investigated. penetration of root tips by juveniles of all species into the m. incognita-resistant nc-89 and g-28 was much less than that on the susceptible mcnair-944. few juveniles of m. incognita were detected in resistant cultivars 7 and 14 days after inoculation. infectio ... | 1983 | 19295823 |
| scanning electron microscopy of perineal patterns of three species of meloidogyne. | the perineal pattern of meloidogyne graminicola is oval, characterized by the anastomosing of cuticular striae converging, and elevating at the tail terminus. a deep lateral incisure forming a low arch traverses the rounded perineal pattern of meloidogyne hapla. punctations at the tail region of m. hapla are not observed with the scanning electron microscope. minute crosslines invaginate with the vulvar lips of meloidogyne incognita. punctate indentations around the anal opening and bordering th ... | 1978 | 19305825 |
| temperature-induced phase transitions in nematode lipids and their influence on respiration. | temperature-induced phase transitions estimated by electron spin resonance (esr) technique were ohscrved in the lipids of several nematode species. in both meloidogyne javanica and caenorhahditis elegans, there was a phase transition in their phospholipids from a liquid-crystalline state to a solid gel state at about 10 c. aphelenchus avenae also had a phase transition, but at about 20 c. with this species, the spin-label motion parameters indicated the transition was from the liquid-crystalline ... | 1975 | 19308140 |
| correlations of field populations of nematodes with crop growth responses for determining relative involvement of species. | treated and nontreated field plots were assayed, and the population density of each plant-parasitic nematode present was compared with crop growth and yield and with the population densities of other nematode species in the same plots. the strongest correlations between nematode population densities and growth responses occurred when soil assays for nematodes were made 55-73 days after planting. belonolairnus longicaudatus was the most damaging parasite on peanut, arachis hypogaea, as evidenced ... | 1975 | 19308153 |
| influence of pratylenchus vulnus and meloidogyne hapla on the growth of rootstocks of rose. | pratylenchus vulnus is involved in a desease of rosa noisettiana 'manetti' rose rootstock characterized by darkening of roots, death of feeder roots, and stunting of entire plants. the disease is more severe when plants are grown in silt loam soil than when they are grown in sandy loam soil. the nematodes reproduce best in silt loam soil at 20 c. meloidogyne hapla did not affect the growh of manetti. rosa sp. 'dr. huey', manetti, and r. odorata rose rootstocks were found to be goos hosts for p. ... | 1976 | 19308189 |
| influence of nematodes and light sources on growth and nodulation of soybean. | the influence of nematodes on nodulation of soybean varied according to their modes of parasitism. in the greenhouse, nodule formation was stimulated by the endoparasites, meloidogyne hapla and pratylenchus penetrans, but was inhibited slightly by the ectoparasite, belonolaimus longicaudatus. in an experiment under controlled conditions in a phytotron, heterodera glycines severely inhibited nodule formation, whereas plants inoculated with b. longicaudatus and p. penetrans had more nodules per g ... | 1976 | 19308196 |
| effects of temperature and inoculation timing on the meloidogyne hapla/corynebacterium insidiosum complex in alfalfa. | | 1972 | 19319247 |
| survival and reproduction of some nematodes as affected by muck and organic acids. | fulvic, humic, acetic, n-bulyric, formic, lactic, and propionic acids were inhibitory to the survival or reproduction of aphelenchus avenae, aphelenchoides goodeyi, helicotylenchus pseudorobustus, meloidogyne hapla or xiphinema americanum. reproduction of h. pseudorobustus and m. hapla significantly increased with increasing amounts of muck added to sand, and with the initial amount of nematode inoculum. all acids except humic and fulvic were lethal, in vitro, to all nematode species tested. whe ... | 1973 | 19319297 |
| occurrence, parasitism, and pathogenicity of nematodes associated with sycamore (platanus occidentalis l.). | ten species of stylet-bearing nematodes were recovered in a survey of sycamore (platanus occidentalis l. ) stands in georgia. helicotylenchus, xiphinema, and criconemoides were the genera found most frequently. populations of hoplolaimus galeatus, scutellonema brachyurum, helicotylenchus dihystera and h. pseudorobustus increased on greenhouse-grown sycamore, but trichodorus christiei, xiphinema americanum, meloidogyne hapla, m. arenaria and m. incognita did not. hoplolaimus galeatus and s. brach ... | 1971 | 19322367 |
| peanut pod invasion by aspergillus flavus in the presence of meloidogyne hapla. | 'argentine', 'early runner' and 'florigiant' peanut cultivars were grown in methyl bromide treated soil in field microplots inoculated with: (i) aspergillus flavus or (ii) a. flavus + meloidogyne hapla. nematode infection produced heavy root galling and light pod galling equally on all cultivars. a. flavus, a. niger, cephalosporium spp., colletotrichum sp., curvularia spp., fusarium spp., penicillium spp. and trichoderma viride were isolated from shells and kernels. a significantly greater incid ... | 1969 | 19325693 |
| a putative nuclear growth factor-like globular nematode specific protein. | expressed sequence tags (ests) are an effective approach for discovery of novel genes. in the current study, approximately 250 ests of the cattle parasitic nematode setaria digitata were examined and a cdna clone identified whose coding sequence could not be functionally annotated by searching over publicly available genome, protein, est and sts databases. here, we report the extensive characterization of this orf (up) and its homologues using a bioinformatic approach. uncharacterized protein (s ... | 2009 | 19759810 |
| proteomic and bioinformatic analysis of the root-knot nematode meloidogyne hapla: the basis for plant parasitism. | on the basis of the complete genome sequence of the root-knot nematode melodogyne hapla, we have deduced and annotated the entire proteome of this plant-parasite to create a database of 14,420 proteins. we have made this database, termed happep3, available from the superfamily repository of model organism proteomes (http://supfam.mrc-lmb.cam.ac.uk/superfamily). to experimentally confirm the happep3 assignments using proteomics, we applied a data-independent lc/ms(e) analysis to m. hapla protein ... | 2010 | 20804128 |
| rnai effector diversity in nematodes. | while rna interference (rnai) has been deployed to facilitate gene function studies in diverse helminths, parasitic nematodes appear variably susceptible. to test if this is due to inter-species differences in rnai effector complements, we performed a primary sequence similarity survey for orthologs of 77 caenorhabditis elegans rnai pathway proteins in 13 nematode species for which genomic or transcriptomic datasets were available, with all outputs subjected to domain-structure verification. our ... | 2011 | 21666793 |
| Activity of Meadowfoam ( Limnanthes alba ) Seed Meal Glucolimnanthin Degradation Products against Soilborne Pathogens. | Meadowfoam ( Limnanthes alba L.) is a herbaceous winter-spring annual grown as a commercial oilseed crop. The meal remaining after oil extraction from the seed contains up to 4% of the glucosinolate glucolimnanthin. Degradation of glucolimnanthin yields toxic breakdown products, and therefore the meal may have potential in the management of soilborne pathogens. To maximize the pest-suppressive potential of meadowfoam seed meal, it would be beneficial to know the toxicity of individual glucolimn ... | 2011 | 22142246 |
| relationship of resistance to meloidogyne chitwoodi (race 2) and m. hapla in alfalfa. | in the pacific northwest, alfalfa (medicago sativa) is host to two species of root-knot nematodes, including race 2 of the columbia root-knot nematode (meloidogyne chitwoodi) and the northern root-knot nematode (meloidogyne hapla). in addition to the damage caused to alfalfa itself by m. hapla, alfalfa's host status to both species leaves large numbers of nematodes available to damage rotation crops, of which potato is the most important. a nematode-resistant alfalfa germplasm release, w12sr2w1, ... | 2012 | 23483826 |
| comprehensive transcriptome profiling in tomato reveals a role for glycosyltransferase in mi-mediated nematode resistance. | root-knot nematode (rkn; meloidogyne spp.) is a major crop pathogen worldwide. effective resistance exists for a few plant species, including that conditioned by mi in tomato (solanum lycopersicum). we interrogated the root transcriptome of the resistant (mi+) and susceptible (mi-) cultivars 'motelle' and 'moneymaker,' respectively, during a time-course infection by the mi-susceptible rkn species meloidogyne incognita and the mi-resistant species meloidogyne hapla. in the absence of rkn infectio ... | 2007 | 17434994 |
| opda has key role in regulating plant susceptibility to the root-knot nematode meloidogyne hapla in arabidopsis. | jasmonic acid (ja) is a plant hormone that plays important roles in regulating plant defenses against necrotrophic pathogens and herbivorous insects, but the role of ja in mediating the plant responses to root-knot nematodes has been unclear. here we show that an application of either methyl jasmonate (meja) or the ja-mimic coronatine (cor) on arabidopsis significantly reduced the number of galls caused by the root-knot nematode meloidogyne hapla. interestingly, the meja-induced resistance was i ... | 2016 | 27822219 |
| specific microbial attachment to root knot nematodes in suppressive soil. | understanding the interactions of plant-parasitic nematodes with antagonistic soil microbes could provide opportunities for novel crop protection strategies. three arable soils were investigated for their suppressiveness against the root knot nematode meloidogyne hapla. for all three soils, m. hapla developed significantly fewer galls, egg masses, and eggs on tomato plants in unsterilized than in sterilized infested soil. egg numbers were reduced by up to 93%. this suggested suppression by soil ... | 2014 | 24532076 |
| nematode-trapping fungi: evaluation of axenic healthy and galled roots as trap inducers. | larvae of meloidogyne hapla chit. induced abundant trap formation in the predaceous fungus arthrobotrys conoides drechs. under similar aseptic conditions, neither healthy roots of lycopersicon esculentum mill, nor roots parasitized by the root-knot nematode induced traps. | 1964 | 14190248 |
| interspecific and host-related gene expression patterns in nematode-trapping fungi. | nematode-trapping fungi are soil-living fungi that capture and kill nematodes using special hyphal structures called traps. they display a large diversity of trapping mechanisms and differ in their host preferences. to provide insights into the genetic basis for this variation, we compared the transcriptome expressed by three species of nematode-trapping fungi (arthrobotrys oligospora, monacrosporium cionopagum and arthrobotrys dactyloides, which use adhesive nets, adhesive branches or constrict ... | 2014 | 25384908 |
| biological control of meloidogyne hapla on alfalfa and tomato with the fungus meria coniospora. | this study was to determine whether arthrobotrys flagrans, a. oligospora, and meria coniospora would control the root-knot nematode meloidogyne hapla on alfalfa and tomato. alfalfa seeds were coated with a fungus-rye powder in 2% cellulose and were planted in infested soil. three-week-old seedlings from seed treated with m. coniospora had 60% and 58% fewer galls in two experiments than did seedlings from untreated seeds. numbers of j2 in the soil were not reduced. plant growth did not improve. w ... | 1989 | 19287596 |
| genomes of parasitic nematodes (meloidogyne hapla, meloidogyne incognita, ascaris suum and brugia malayi) have a reduced complement of small rna interference pathway genes: knockdown can reduce host infectivity of m. incognita. | the discovery of rna interference (rnai) as an endogenous mechanism of gene regulation in a range of eukaryotes has resulted in its extensive use as a tool for functional genomic studies. it is important to study the mechanisms which underlie this phenomenon in different organisms, and in particular to understand details of the effectors that modulate its effectiveness. the aim of this study was to identify and compare genomic sequences encoding genes involved in the rnai pathway of four parasit ... | 2016 | 27126863 |
| biological control of meloidogyne hapla using an antagonistic bacterium. | we examined the efficacy of a bacterium for biocontrol of the root-knot nematode (rkn) meloidogyne hapla in carrot (daucus carota subsp. sativus) and tomato (solanum lycopersicum). among 542 bacterial isolates from various soils and plants, the highest nematode mortality was observed for treatments with isolate c1-7, which was identified as bacillus cereus based on cultural and morphological characteristics, the biolog program, and 16s rrna sequencing analyses. the population density and the nem ... | 2014 | 25289015 |
| the diverse nematicidal properties and biocontrol efficacy of bacillus thuringiensis cry6a against the root-knot nematode meloidogyne hapla. | cry6a toxin from bacillus thuringiensis is a representative nematicidal crystal protein with a variety of nematicidal properties to free-living nematode caenorhabditis elegans. cry6a shares very low homology and different structure with cry5b, another representative nematicidal crystal protein, and probably acts in a distinct pathway. all these strongly indicate that cry6a toxin is likely a potent candidate for nematicide. the present study dealt with global investigation to determine the detrim ... | 2015 | 25556591 |
| in vitro uptake of 140 kda bacillus thuringiensis nematicidal crystal proteins by the second stage juvenile of meloidogyne hapla. | plant-parasitic nematodes (ppns) are piercing/sucking pests, which cause severe damage to crops worldwide, and are difficult to control. the cyst and root-knot nematodes (rkn) are sedentary endoparasites that develop specialized multinucleate feeding structures from the plant cells called syncytia or giant cells respectively. within these structures the nematodes produce feeding tubes, which act as molecular sieves with exclusion limits. for example, heterodera schachtii is reportedly unable to ... | 2012 | 22737212 |
| phylogenetic diversity of bacterial endophytes of panax notoginseng with antagonistic characteristics towards pathogens of root-rot disease complex. | endophytes play an important role in protection of host plants from infection by phytopathogens. endophytic bacteria were isolated from five different parts (root, stem, petiole, leaf and seed) of panax notoginseng and evaluated for antagonistic activity against fusarium oxysporum, ralstonia sp. and meloidogyne hapla, three major pathogens associated with root-rot disease complex of p. notoginseng. from 1000 endophytic bacterial strains evaluated in vitro, 104 strains exhibited antagonistic prop ... | 2013 | 22987248 |
| trichinella spiralis: adaptation and parasitism. | publication of the genome from the clade i organism, trichinella spiralis, has provided us an avenue to address more holistic problems in parasitology; namely the processes of adaptation and the evolution of parasitism. parasitism among nematodes has evolved in multiple, independent events. deciphering processes that drive species diversity and adaptation are keys to understanding parasitism and advancing control strategies. studies have been put forth on morphological and physiological aspects ... | 2016 | 27425574 |
| phylum-level conservation of regulatory information in nematodes despite extensive non-coding sequence divergence. | gene regulatory information guides development and shapes the course of evolution. to test conservation of gene regulation within the phylum nematoda, we compared the functions of putative cis-regulatory sequences of four sets of orthologs (unc-47, unc-25, mec-3 and elt-2) from distantly-related nematode species. these species, caenorhabditis elegans, its congeneric c. briggsae, and three parasitic species meloidogyne hapla, brugia malayi, and trichinella spiralis, represent four of the five maj ... | 2015 | 26020930 |
| versatile glycoside hydrolase family 18 chitinases for fungi ingestion and reproduction in the pinewood nematode bursaphelenchus xylophilus. | the glycoside hydrolase family 18 (gh18) of chitinases is a gene family widely expressed in archaes, prokaryotes and eukaryotes, and hydrolyzes the β-1,4-linkages in chitin. the pinewood nematode bursaphelenchus xylophilus is one of the organisms that produces gh18 chitinases. notably, b. xylophilus has a higher number of gh18 chitinases compared with the obligate plant-parasitic nematodes meloidogyne incognita and meloidogyne hapla. in this study, seven gh18 chitinases were identified and clone ... | 2016 | 27641827 |
| exploitation of fta cartridges for the sampling, long-term storage, and dna-based analyses of plant-parasitic nematodes. | the use of dna-based analyses in molecular plant nematology research has dramatically increased over recent decades. therefore, the development and adaptation of simple, robust, and cost-effective dna purification procedures are required to address these contemporary challenges. the solid-phase-based approach developed by flinders technology associates (fta) has been shown to be a powerful technology for the preparation of dna from different biological materials, including blood, saliva, plant t ... | 2014 | 24093923 |
| interaction of ditylenchus dipsaci and meloidogyne hapla on resistant and susceptible plant species. | numbers ofditylenchus dipsaci or meloidogyne hapla invading ranger alfalfa, tender crop bean, stone improved tomato, ah-14 sugarbeet, yellow sweet clover, and wasatch wheat from single inoculations were not significantly different from numbers by invasion of combined inoculations. d. dipsaci was recovered only from shoot and m. hapla only from root tissue. combined inoculations did not affect reproduction of either d. dipsaci or m. hapla. d. dipsaci suppressed shoot growth of all species at 15-3 ... | 1987 | 19290168 |
| interrelationship of meloidogyne hapla and ditylenchus dipsaci on resistant and susceptible alfalfa. | simultaneous inoculations of alfalfa with meloidogyne hapla larvae and ditylenchus dipsaci at 16, 20, 24, and 28 c did not depress penetration of either nematode in 'nev syn xx' -a selection resistant to m. hapla and d. dipsaci, 'vernal 298' -a selection resistant to m. hapla and susceptible to d. dipsaci, 'lahontan' -a cultivar resistant to d. dipsaci and susceptible to m. hapla, and 'ranger' -a cultivar susceptible to both m. hapla and d, dipsaci. infection with d. dipsaci depressed growth of ... | 1980 | 19300705 |
| attraction of ditylenchus dipsaci and meloidogyne hapla by resistant and susceptible alfalfa seedlings. | ditylenchus dipsaci kühn were equally attracted to and equally invaded resistant ('lahontan') and susceptible ('ranger') germinating alfalfa (medicago sativa l.) seedlings exposed singly in moist sand except at a distance of 12.5 mm at 20 c when the susceptibles proved more attractive than the resistants. larvae hatching from egg-masses of meloidogyne hapla chitwood were also attracted equally to germinating seedlings of resistant ('m-9') and susceptible ('lahontan') alfalfa offered singly. when ... | 1971 | 19322372 |
| plant parasitic nematodes: a new mechanism for injury of hosts. | pathological effects of ditylenchus dipsaci and meloidogyne hapla are related to the disturbance of the auxin balance in the host by the nematode. the parasites produce an auxin inactivator, apparently enzymatic, that enables ditylenchus dipsaci to stunt host stem apices and meloidogyne hapla to reduce its galling potential. | 1965 | 17790829 |
| improvement of anaerobic soil disinfestation. | with increasing worldwide restrictions for soil fumigants, growers loose an important tool to control soilborne pests and pathogens. environmentally friendly alternatives are urgently needed and anaerobic soil disinfestation (asd) may be one of them. traditional asd with fresh grass is already applied in open field vegetables but the mode of action is unknown. therefore, trials were performed under controlled conditions using soil-filled buckets, in which several processed defined organic materi ... | 2012 | 23885444 |
| distribution of heterodera carotae and meloidogyne hapla in michigan carrot production. | during 1986 and 1988, selected farms in all of the major carrot-growing counties of michigan were surveyed to determine the extent of infestation by heterodera carotae and meloidogyne hapla. both species were found in all eight counties surveyed, but not on all farms. heterodera carotae was recovered from 67.4% of the fields surveyed. meloidogyne hapla was detected in 24.8% of the samples and from 69.8% of the fields. in most cases, h. carotae and m. hapla occurred in the same field. | 1992 | 19283061 |
| using fame analysis to compare, differentiate, and identify multiple nematode species. | we have adapted the sherlock(®) microbial identification system for identification of plant parasitic nematodes based on their fatty acid profiles. fatty acid profiles of 12 separate plant parasitic nematode species have been determined using this system. additionally, separate profiles have been developed for rotylenchulus reniformis and meloidogyne incognita based on their host plant, four species and three races within the meloidogyne genus, and three life stages of heterodera glycines. stati ... | 2009 | 22736811 |
| usefulness of egg assays in nematode population-density determinations. | | 1987 | 19290117 |
| interrelationship of heterodera schachtii and meloidogyne hapla on tomato. | invasion of tomato (lycopersicon esculentum l.) roots by combined and sequential inoculations of meloidogyne hapla and a tomato population of heterodera schachtii was affected more by soil temperature than by nematode competition. maximum invasion of tomato roots, by m. hapla and h. schachtii occurred at 30 and 26 c, respectively. female development and nematode reproduction (eggs per plant) of m. hapla was adversely affected by h. schachtii in combined inoculations of the two nematode species. ... | 1985 | 19294113 |
| relationship between heterodera schachtii, meloidogyne hapla, and nacobbus aberrans on sugarbeet. | heterodera schachtii, meloidogyne hapla, and nacobbus aberrans either alone, or in various combinations with each other, can, when inoculated at a concentration of 12 second-stage juveniles/ cm(3) of soil, cause a significant (p = 0.01) suppression of growth of sugarbeet (cv. tasco ah14) seedlings. m. hapla and h. schachtii decreased growth of sugarbeet more than n. aberrans over a 60-day period. the adverse effect of n. aberrans on the final population/initial population (pf/pi) ratio for eithe ... | 1984 | 19295890 |
| influence of meloidogyne hapla chitwood, 1949 on development and establishment of heterodera schachtii schmidt, 1871 on beta vulgaris l. | influence of meloidogyne hapla on estahlishnrent and maturity of heterodera schachtii in sugarbeet was studied. results indicated that when the majority of m. hapla were in second, third, or fourth larval stages within plants prior to h. schachtii inoculation, growth and development of the latter was retarded. however, when m. hapla reached the young female stage prior to inoculation of h. schachtii, establishment and development of the latter was greatly enhanced. as m. hapla reached maturity b ... | 1983 | 19295848 |
| pathological interaction of a combination of heterodera schachtii and meloidogyne hapla on tomato. | increased culturing of a tomato population of heterodera schachtii (ut1c) on tomato for 480 days (eight inoculation periods of 60 days each) significantly increased virulence to 'stone improved' tomato. a synergistic relationship existed between meloidogyne hapla and h. schaehtii on tomato. a combination of h. schachtii (utic) and m. hapla significantly reduced tomato root weights by 65, 64, and 61% below root weights of untreated controls, and single inoculations of m. hapla and h. schachtii, r ... | 1982 | 19295694 |
| interacting effects of soil temperature and type on reproduction and pathogenicity of heterodera schachtii and meloidogyne hapla on sugarbeets. | | 1979 | 19300649 |
| effects of oxamyl on the reproduction of meloidogyne hapla and heterodera schachtii. | | 1978 | 19305874 |
| histopathology of beta vulgaris to individual and concomitant infections by meloidogyne hapla and heterodera schachtii. | histological changes in roots of beta vulgaris cultivar 'ush9a' resulting from infection of meloidogyne hapla alone, heterodera schachtii alone, or infection by both species on one feeding site were studied. anatomical changes caused by m. hapla infection were characterized by regions of hypertrophy and hyperplasia. giant cells were formed within the stele and varied in numbers from 4-7/feeding site; hyperplasia occurred in the form of a large number of relatively small compacted cells generally ... | 1976 | 19308244 |
| parasitism of beta vulgaris by meloidogyne hapla and heterodera schachtii alone and in combination. | interrelationships of meloidogyne hapla and heterodera schachtii in combinations of several population levels and different inoculation periods were studied. results indicated suppression of gall development of m. hapla in any treatment in which inoculations of h. schachtii preceded those of m. hapla by 10 days. this interrelationship was characterized by amensalism with m. hapla serving as an amensat and h. schachtii serving as an inhibitor. conversely, when inoculations of m. hapla preceded h. ... | 1976 | 19308223 |
| self-interactions of meloidogyne hapla and of heterodera schachtii on beta vulgaris. | double inoculations of sugar beet with larvae of meloidogyne hapla resulted in a higher galling incidence in only one treatment than did a single inoculation using the same number of larvae. double inoculations with larvae of heterodera schachtii, however, resulted in three- to five-fold more cysts in most cases than did single inoculations using the same number of larvae. in general, plants died more quickly after double inoculations than after single inoculations of the same total number of ei ... | 1976 | 19308195 |
| rkn lethal db: a database for the identification of root knot nematode (meloidogyne spp.) candidate lethal genes. | root knot nematode (rkn; meloidogyne spp.) is one of the most devastating parasites that infect the roots of hundreds of plant species. rkn cannot live independently from their hosts and are the biggest contributors to the loss of the world's primary foods. rnai gene silencing studies have demonstrated that there are fewer galls and galls are smaller when rnai constructs targeted to silence certain rkn genes are expressed in plant roots. we conducted a comparative genomics analysis, comparing rk ... | 2012 | 23144556 |
| host status of endophyte-infected and noninfected tall fescue grass to meloidogyne spp. | tall fescue grass cultivars with or without endophytes were evaluated for their susceptibility to meloidogyne incognita in the greenhouse. tall fescue cultivars evaluated included, i) wild-type jesup (e+, ergot-producing endophyte present), ii) endophyte-free jesup (e-, no endophyte present), iii) jesup (max-q, non-ergot producing endophyte) and iv) georgia 5 (e+). peach was included as the control. peach supported greater (p ≤ 0.05) reproduction of m. incognita than all tall fescue cultivars. d ... | 2010 | 22736851 |
| 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 |
| 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 |
| 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 |
| 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 |
| relative damage functions and reproductive potentials of meloidogyne arenaria and m. hapla on peanut. | the reproductive potential and damage functions for meloidogyne hapla and m. arenaria race 1 on virginia-type peanuts (arachis hypogaea cv. florigiant) were determined over 2 years in microplot experiments in north carolina. peanut yield suppression and damage to pods as a result of galling were greatest in response to m. arenaria (p = 0.01). damage functions for the two species were adequately described by the quadratic models: yield (g/plot) = 398 - 17.1 (log[pi + 1]) - 17.0(log[pi + 1])(2); ( ... | 1992 | 19283222 |
| host suitability and response of asparagus cultivars to meloidogyne species and races. | the host-parasite relationships of asparagus and meloidogyne spp. were examined under greenhouse and microplot conditions. meloidogyne species and races differed greatly in their ability to reproduce on asparagus seedlings. meloidogyne hapla generally failed to reproduce, and m. javanica, m. arenaria race 1, and m. incognita race 3 reproduced poorly, with a reproduction factor (rf = final population/initial population) usually < 1.0. only m. arenaria race 2 and m. incognita races 1 and 4 reprodu ... | 1992 | 19283211 |
| resistance to root-knot nematodes in cucumber and horned cucumber. | two experiments were conducted in the greenhouse. in one experiment, cucumber (cucumis sativus) and horned cucumber (c. metuliferus) cultigens were evaluated for resistance to four root-knot nematode species (meloidogyne arenaria, m. hapla, m. incognita, and m. javanica), and, in a second experiment, a standard (12-week) test was compared with a rapid (6-week) test. in the first experiment, horned cucumber cultigens varied in response to the meloidogyne species. 'sumter' cucumber was more suscep ... | 1991 | 19283171 |
| resistance in lycopersicon peruvianum to isolates of mi gene-compatible meloidogyne populations. | root-knot nematode resistance of f progeny of an intraspecific hybrid (lycopersicon peruvianum var. glandulosum acc. no. 126443 x l. peruvianum acc. no. 270435), l. esculentum cv. piersol (possessing resistance gene mi), and l. esculentum cv. st. pierre (susceptible) was compared. resistance to 1) isolates of two meloidogyne incognita populations artificially selected for parasitism on tomato plants possessing the mi gene, 2) the wild type parent populations, 3) four naturally occurring resistan ... | 1990 | 19287762 |
| variation in virulence within meloidogyne chitwoodi, m. fallax, and m. hapla on solanum spp. | abstract the virulence of meloidogyne hapla, m. chitwoodi, and m. fallax was studied on genotypes of solanum spp. in a greenhouse. juveniles of 11 m. hapla race a isolates, 3 m. hapla race b isolates, and 5 mono-female lines of a m. hapla race a isolate were inoculated on s. chacoense, s. hougasii, and s. sparsipilum. juveniles of eight m. chitwoodi isolates, five m. fallax isolates, and six mono-female lines of a m. chitwoodi isolate were inoculated on s. bulbocastanum, s. chacoense, s. hougasi ... | 1998 | 18944937 |
| effect of the mi gene in tomato on reproductive factors of meloidogyne chitwoodi and m. hapla. | the effect of the mi gene on the reproductive factor of meloidogyne chitwoodi and m. hapla, major nematode pests of potato, was measured on nearly isogenic tomato lines differing in presence or absence of the mi gene. the mi allele controlled resistance to reproduction of race 1 of m. chitwoodi and to one of two isolates of race 2. no resistance to race 3 of m. chitwoodi or to m. hapla was found. variability in response to isolates of race 2 may reflect diversity of virulence genotypes heretofor ... | 1997 | 19274176 |
| importance of temperature in the pathology of meloidogyne hapla and m. chitwoodi on legumes. | effects of temperatures on the host-parasite relationships were studied for three legume species and four populations of root-knot nematodes from the western united states. the nematode populations were meloidogyne hapla from california (mhca), utah (mhut), and wyoming (mhwy), and a population of m. chitwoodi from utah (mcut). the legumes were milkvetch (astragalus cicer), alfalfa (medicago sativa), and yellow sweet clover (melilotus officinalis). all milkvetch plants survived inoculation with a ... | 1997 | 19274139 |
| a pcr assay to identify and distinguish single juveniles of meloidogyne hapla and m. chitwoodi. | random amplified polymorphic dna (rapd) bands that distinguish meloidogyne hapla and m. chitwoodi from each other, and from other root-knot nematode species, were identified using a series of random octamer primers. the species-specific amplified dna fragments were cloned and sequenced, and then the sequences were used to design 20-mer primer pairs that specifically amplified a dna fragment from each species. using the primer pairs, successful amplifications from single juveniles were readily at ... | 1997 | 19274128 |
| host suitability of twelve leguminosae species to populations of meloidogyne hapla and m. chitwoodi. | legumes of the genera astragalus (milkvetch), coronilla (crownvetch), lathyrus (pea vine), lotus (birdsfoot trefoil), medicago (alfalfa), melilotus (clover), trifolium (clover), and vicia (common vetch) were inoculated with a population of melaidogyne chitwoodi from utah or with one of three m. hapla populations from california, utah, and wyoming.thirty-nine percent to 86% of alfalfa (m. scutellata) and 10% to 55% of red clover (t. pratense) plants survived inoculation with the nematode populati ... | 1996 | 19277158 |