| reproduction of belonolaimus longicaudatus, meloidogyne javanica, paratrichodorus minor, and pratylenchus brachyurus on pearl millet (pennisetum glaucum). | pearl millet (pennisetum glaucum) has potential as a grain crop for dryland crop production in the southeastern united states. whether or not pearl millet will be compatible in rotation with cotton (gossypium hirsutum), corn (zea mays), and peanut (arachis hypogaea) will depend, in part, on its host status for important plant-parasitic nematodes of these crops. the pearl millet hybrid 'tifgrain 102' is resistant to both meloidogyne incognita race 3 and m. arenaria race 1; however, its host statu ... | 2005 | 19262863 |
| effect of soils from six management systems on root-knot nematodes and plant growth in greenhouse assays. | the effects of soil management systems on root-knot nematode (meloidogyne incognita) eggs and gall incidence on tomato (lycopersicon esculentum) and cucumber (cucumis sativus) following tomato were evaluated. soil was collected from a replicated field experiment in which six management systems were being assessed for vegetable production. soil management systems were conventional production, organic production, bahiagrass (paspalum notatum) pasture, bahiagrass: stylosanthes (stylosanthes guianen ... | 2005 | 19262892 |
| in-vitro assays of meloidogyne incognita and heterodera glycines for detection of nematode-antagonistic fungal compounds. | in-vitro methods were developed to test fungi for production of metabolites affecting nematode egg hatch and mobility of second-stage juveniles. separate assays were developed for two nematodes: root-knot nematode (meloidogyne incognita) and soybean cyst nematode (heterodera glycines). for egg hatch to be successfully assayed, eggs must first be surface-disinfested to avoid the confounding effects of incidental microbial growth facilitated by the fungal culture medium. sodium hypochlorite was mo ... | 1999 | 19270887 |
| effect of three plant residues and chicken manure used as biofumigants at three temperatures on meloidogyne incognita infestation of tomato in greenhouse experiments. | plant residues of broccoli, melon, and tomato with or without addition of chicken manure were used as biofumigants in two pot experiments with meloidogyne incognita-infested soils. the efficacy of these biofumigants in controlling m. incognita infestation in susceptible tomato bio-assay plants was studied at soil temperatures of 20 masculine, 25 masculine, and 30 masculinec. none of the plant residues was effective at 20 masculinec, and broccoli was more effective than tomato or melon at 25 masc ... | 2005 | 19262896 |
| management of root-knot and reniform nematodes in ultra-narrow row cotton with 1,3-dichloropropene. | ultra-narrow row cotton studies were conducted during 1999 at two field sites in northern florida. one site was naturally infested with meloidogyne incognita race 3 and the other with rotylenchulus reniformis. the fumigant 1,3-dichloropropene (1,3-d) was applied broadcast at rates of 0, 16, 32, 48, 64, 80, and 96 kg ai./ha in replicated plots before planting delta pine 655 brr cotton in 25-cm-wide rows. post-harvest soil population densities at the root-knot nematode site had a significant (p </ ... | 2001 | 19265894 |
| peanut-cotton-rye rotations and soil chemical treatment for managing nematodes and thrips. | in the southeastern united states, a cotton-peanut rotation is attractive because of the high value and extensive planting of both crops in the region. the objective of this experiment was to determine the effects of cotton-peanut rotations, rye, and soil chemical treatments on management of plant-parasitic nematodes, thrips, and soilborne fungal diseases and on crop yield. peanut-cotton-rye rotations were conducted from 1988 to 1994 on tifton loamy sand (plinthic kandiudult) infested primarily ... | 1998 | 19274213 |
| identification of sources of resistance to four species of root-knot nematodes in tobacco. | resistance to the southern root-knot nematode, meloidogyne incognita races 1 and 3, has been identified, incorporated, and deployed into commercial cultivars of tobacco, nicotiana tabacum. cultivars with resistance to other economically important root-knot nematode species attacking tobacco, m. arenaria, m. hapla, m. javanica, and other host-specific races of m. incognita, are not available in the united states. twenty-eight tobacco genotypes of diverse origin and two standard cultivars, nc 2326 ... | 1999 | 19270897 |
| 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 |
| 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 |
| survey of heterodera glycines races and other plant-parasitic nematodes on soybean in north carolina. | a survey of soybean-production areas in the piedmont, coastal plain and tidewater regions of north carolina was conducted from 1994 to 1996. heterodera glycines was detected in 55 of 77 fields sampled in 15 counties. the host race of h. glycines was determined for 39 of the populations collected. of all populations collected, 4% were race 1, 40% race 2, 16% race 4, 7% race 5, and 4% race 9; the remaining 29% could not be accurately categorized. none of the populations evaluated had high levels o ... | 1998 | 19274248 |
| 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 |
| nematicidal activity of fatty acid esters on soybean cyst and root-knot nematodes. | researchers have indicated that the c fatty acid, pelargonic acid (nonanoic acid), has considerable nematicidal activity that could be increased by derivitization and improved emulsification. microemulsions of methyl and ethylene glycol esters of pelargonic acid developed by mycogen corporation (san diego, ca) were tested for nematicidal activity against root-knot and soybean cyst nematodes. all treamaents were compared to a deionized water control and a microemulsion "blank" (minus active ingre ... | 1997 | 19274268 |
| effect of temperature on suppression of meloidogyne incognita by tagetes cultivars. | the suppression of meloidogyne incognita by marigolds differed among six marigold cultivars and five soil temperatures. tagetes signata (syn. t. tenuifolia) cv. tangerine gem and the tagetes hybrid polynema allowed reproduction and root galling when grown at 30 degrees c, and should not be used for control of m. incognita at temperatures close to 30 degrees c. tagetes patula cultivars single gold and tangerine and t. erecta flor de muerto, when grown within a 20-30 degrees c soil temperature ran ... | 1999 | 19270940 |
| replacement series: a tool for characterizing competition between phytoparasitic nematodes. | the replacement series approach was used to detect and define competition between meloidogyne incognita (mi) and rotylenchulus reniformis (rr) on soybean. in three greenhouse tests, soybean cv. davis seedlings were inoculated with 1,000 vermiform nematodes in the following mi:rr ratios: 0:0, 100:0, 75:25, 50:50, 25:75, and 0:100. after 86 days, relative nematode-yield values (number of each species in mixed culture divided by number in nonmixed culture) were calculated based on nematodes in soil ... | 1997 | 19274132 |
| a survey of plant-parasitic nematodes associated with cotton in northeastern louisiana. | a survey was conducted in northeastern louisiana to determine the frequency and abundance of plant-parasitic nematodes associated with cotton. in fall 1997 and 1998, more than 600 soil samples were collected from cotton fields representing 6,200 ha, which is 5.3% of the cotton production hectarage in this region. composite soil samples were collected from 10 ha in each field. nematodes were extracted by gravity screening and sucrose centrifugation, identified to genus, and quantified. nine gener ... | 2000 | 19271002 |
| meloidogyne incognita infested soil amended with chicken litter. | the effects of chicken litter on meloidogyne incognita in cotton, gossypium hirsutum cv. dpl50 were determined in field microplots. litters (manure and pine-shaving bedding) from a research facility and a commercial broiler house were used. treatments consisted of 0.25%, 0.5%, and 1% litter by dry weight of soil for each kind of litter. three control treatments consisted of soil not amended with litter, with and without nematodes, and one treatment to which mineral fertilizer was added at a nitr ... | 1996 | 19277155 |
| chemical-mediated toxicity of n-viro soil to heterodera glycines and meloidogyne incognita. | n-viro soil (nvs) is an alkaline-stabilized municipal biosolid that has been shown to lower population densities and reduce egg hatch of heterodera glycines and other plant-parasitic nematodes; but the mechanism(s) of nematode suppression of this soil amendment are unknown. this study sought to identify nvs-mediated changes in soil chemical properties and their impact upon h. glycines and meloidogyne incognita mortality. n-viro soil was applied to sand in laboratory assays at 0.5%, 1.0%, 2.0%, a ... | 2004 | 19262820 |
| 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 |
| 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 |
| competition between heterodera glycines and meloidogyne incognita or pratylenchus penetrans: independent infection rate measurements. | competition on soybean between heterodera glycines (race 3) and meloidogyne incognita or h. glycines and pratylenchus penetrans were investigated in greenhouse experiments. each pair of nematode species was mixed in 3-ml suspensions at ratios of 1,000:0, 750:250, 500:500, 250:750, and 0:1,000 second-stage juveniles or mixed stages for p. penetrans. nematodes from a whole root system were counted and infection rates standardized per 1,000 nematodes (per replication) prior to testing the null hypo ... | 2003 | 19265967 |
| factors affecting the suppression of heterodera glycines by n-viro soil. | previous laboratory research demonstrated that n-viro soil (nvs), an alkaline-stabilized municipal biosolid, suppressed plant-parasitic nematodes. this study continued to explore the use of nvs as a nematode management tool specifically addressing factors that could influence its use. n-viro soil from different locations, the components of nvs (de-watered biosolids and fly ash admixtures), and sterilized nvs were applied to sand microcosms to determine effects on nematode survival sand solution ... | 2005 | 19262864 |
| rotations with coastal bermudagrass and fallow for management of meloidogyne incognita and soilborne fungi on vegetable crops. | the efficacy of fallow and coastal bermudagrass (cynodon dactylon) as a rotation crop for control of root-knot nematode (meloidogyne incognita race 1) and soilborne fungi in okra (hibiscus esculentus cv. emerald), squash (cucurbita pepo cv. dixie hybrid), and sweet corn (zea mays cv. merit) was evaluated in a 3-year field trial. numbers of m. incognita in the soil and root-gall indices were greater on okra and squash than sweet corn and declined over the years on vegetable crops following fallow ... | 1995 | 19277312 |
| variability of meloidogyne exigua on coffee in the zona da mata of minas gerais state, brazil. | minas gerais is the major coffee-producing state of brazil, with 28% of its production coming from the region of zona da mata. four major species of root-knot nematode attacking coffee (meloidogyne incognita, m. paranaensis, m. coffeicola, and m. exigua) have been reported from brazil. to determine the variability in meloidogyne spp. occurring in that region, 57 populations from 20 localities were evaluated for morphological, enzymatic, and physiological characteristics. according to the perinea ... | 2005 | 19262880 |
| effects of monoclonal antibodies, cationized ferritin, and other organic molecules on adhesion of pasteuria penetrans endospores to meloidogyne incognita. | the incidence of adhesion of pasteuria penetrans endospores to meloidogyne incognita second-stage juveniles (j2) was studied after pretreatment of the latter with monoclonal antibodies (mab), cationized ferritin, and other organic molecules in replicated trials. monoclonal antibodies developed to a cuticular epitope of m. incognita second-stage juveniles gave significant reductions in attachment of p. penetrans endospores to treated nematodes. mab bound to the entire length of j2 except for the ... | 1997 | 19274193 |
| pathogenicity of pratylenchus penetrans, heterodera glycines, and meloidogyne incognita on soybean genotypes. | the pathogenicity of heterodera glycines, meloidogyne incognita, and pratylenchus penetrans on h. glycines-resistant 'bryan,' tolerant-susceptible 'g88-20092,' and intolerant-susceptible 'tracy m' soybean cultivars was tested using plants grown in 800 cm(3) of soil in 15-cm-diam. clay pots in three greenhouse experiments. plants were inoculated with 0, 1,000, 3,000, or 9,000 h. glycines race 3 or m. incognita eggs, or vermiform stages of p. penetrans/pot. forty days after inoculation, nmnbers of ... | 1998 | 19274203 |
| the potential of thiarubrine c as a nematicidal agent against plant- parasitic nematodes. | thiarubrine c, a polyacetylenic 1,2-dithiin isolated from the roots of rudbeckia hirta (asteraceae), exhibited strong nematicidal activity in in vitro and growth chamber assays. thiarubrine c was toxic, in the absence of light, to the plant-parasitic nematodes meloidogyne incognita and pratylenchus penetrans at lcs of 12.4 ppm and 23.5 ppm, respectively. a minimum exposure time between 12 and 24 hours was the critical period for nematode mortality due to thiarubrine c. although thiarubrine c was ... | 1998 | 19274210 |
| caenorhabditis elegans: a genetic guide to parasitic nematode biology. | the advent of parasite genome sequencing projects, as well as an increase in biology-directed gene discovery, promises to reveal genes encoding many of the key molecules required for nematode-host interactions. however, distinguishing parasitism genes from those merely required for nematode viability remains a substantial challenge. although this will ultimately require a functional test in the host or parasite, the free-living nematode caenorhabditis elegans can be exploited as a heterologous s ... | 1998 | 19274223 |
| 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 |
| 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 |
| crop yields and nematode population densities in triticale-cotton and triticale-soybean rotations. | triticale cv. beagle 82, cotton cv. mcnair 235, and soybean cv. twiggs were arranged in three cropping sequences to determine the effects of fenamiphos and cropping sequence on nematode population densities and crop yields under conservation tillage for 4 years. the cropping sequences were triticale (t)-cotton (c)-t-c, t-soybean (s)-t-s, and t-c-t-s. numbers of meloidogyne incognita second-stage juveniles declined on trificale but increased on cotton and soybean each year. root-gall indices of c ... | 1998 | 19274228 |
| 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 |
| coastal bermudagrass rotation and fallow for management of nematodes and soilborne fungi on vegetable crops. | the efficacy of clean fallow, bermudagrass (cynodon dactylon) as a rotational crop, and fenamiphos for control of root-knot nematode (meloidogyne incognita race 1) and soilborne fungi in okra (hibiscus esculentus), snapbean (phaseolus vulgaris), and pepper (capsicum annuum) production was evaluated in field tests from 1993 to 1995. numbers of m. incognita in the soil and root-gall indices were greater on okra than on snapbean or pepper. application of fenamiphos at 6.7 kg a.i./ha did not suppres ... | 1997 | 19274273 |
| interaction between meloidogyne incognita and fusarium oxysporum f. sp. phaseoli on selected bean genotypes. | four bean genotypes (ipa-1, a-107, a-211, and calima), representing all possible combinations of resistance and susceptibility to fusarium oxysporum f. sp. phaseoli (fop) and meloidogyne incognita, were each inoculated with three population densities of these pathogens. calima and a-107 were resistant to fop; a-107 and a-211 were resistant to m. incognita; and ipa-1 was susceptible to both pathogens. in fop-susceptible lines (ipa-1 and a-211), the presence of m. incognita contributed to an earli ... | 1994 | 19279917 |
| response of meloidogyne spp. to pasteuria penetrans, fungi, and cultural practices in tobacco. | the response of a mixed population of meloidogyne incognita and m. javanica to three cultural practices, tobacco cultivars (two cultivars, differing in resistance to m. incognita), cover treatments (three treatments), and inorganic nitrogen fertilizer (two treatments), pasteuria penetrans, and soil-borne fungi was investigated in a tobacco field in 1991. on all sampling dates, higher densities of root-knot nematodes were observed on tobacco cv. coker 371 gold than on k-326. initially, forage sor ... | 1994 | 19279937 |
| development of a bionematicide with paecilomyces lilacinus to control meloidogyne incognita. | root-knot disease caused by meloidogyne incognita is a matter of grave concern because it affects several economically important crop plants. the use of solid-state fermentation (ssf) may help to elaborate efficient formulations with fungi to be employed in the biologic control of nematodes. attempts were made to select low-cost substrates for spore production of a strain of paecilomyces lilacinus with known nematicide capacity. coffee husks, cassava bagasse, and defatted soybean cake were utili ... | 2004 | 15304741 |
| raphanus sativus, sinapis alba, and fagopyrum esculentum as hosts to meloidogyne incognita, meloidogyne javanica, and plasmodiophora brassicae. | cultivars of oilseed radish (raphanus sativus var. oleifera cv. adagio, nemex, pegletta, renova, siletina, siletta nova, and ultimo), white mustard (sinapis alba cv. albatross, emergo, maxi, martigena, metex, and serval), buckwheat (fagopyrum esculentum cv. prego, tardo), and phacelia (phacelia tanacetifolia cv. angelia) were tested for susceptibility to meloidogyne incognita race 3 and meloidogyne javanica. experiments were conducted in growth chambers at 25 c and 16 hours light for 42 days aft ... | 1994 | 19279960 |
| response of some common annual bedding plants to three species of meloidogyne. | twelve ornamental bedding plant cultivars were grown in soil infested with isolates of meloidogyne incognita race 1, m. javanica, or m. arenaria race 1 in a series of tests in containers in a growth room. root galling (0-5 scale) and eggs/plant were evaluated 8-10 weeks after soil infestation and seedling transplantation. snapdragon, antirrhinum majus cv. first ladies, was extensively galled and highly susceptible (mean gall rating >/=4.2 and >/=14,500 eggs/plant), and celosia argentea cv. centu ... | 1994 | 19279963 |
| unique immunogenic proteins in heterodera glycines eggshells. | polyclonal antibodies were raised against heterodera glycines eggshells to determine the feasibility of developing an immunoassay for h. glycines eggs. an indirect enzyme-linked immunosorbent assay (elisa) was developed from anfisera collected 10 weeks after the initial injection. from serial dilutions of sonicated eggshells or whole eggs, a sensitivity of detection to 5 ng/ml sonicated eggshells or 1 egg of h. glycines was determined. the method of eggshell preparation had no effect on the anti ... | 1997 | 19274159 |
| 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 |
| effects of fly ash, pseudomonas striata and rhizobium on the reproduction of nematode meloidogyne incognita and on the growth and transpiration of pea. | glasshouse experiments were conducted twice to assess the ash amendments (0, 20, and 40% with soil), a phosphate solubilizing microorganism pseudomonas striata and a root-nodule bacterium rhizobium sp on the reproduction of root-knot nematode meloidogyne incognita and on the growth and transpiration of pea. amendments of fly ash with soil had no effect on transpiration. however, m. incognita reduced the rate of transpiration from 1st week onward after inoculation while inoculation of rhizobium s ... | 2005 | 16114471 |
| crop rotation studies with velvetbean (mucuna deeringiana) for the management of meloidogyne spp. | results from a greenhouse experiment at cabrils, spain, with two velvetbean (mucuna deeringiana) accessions (florida and mozambique) growing in sterilized sandy loam and inoculated with meloidogyne arenaria race 2, m. incognita race 1, and m. javanica revealed that the legume was not a host for these nematodes. in contrast, roots of 'clemson spineless' okra (hibiscus esculentum), 'summer crookneck' squash (cucurbita pepo), and 'davis' soybean (glycine max) were galled by all three root-knot nema ... | 1992 | 19283043 |
| management of plant-parasitic nematodes with a chitin-urea soil amendment and other materials. | field trials were conducted with a chitin-urea soil amendment and several other nematicides on four crop-nematode combinations: tomato-meloidogyne incognita; potato-meloidogyne chitwoodi; walnut-pratylenchus vulnus; and brussels sprouts-heterodera schachtii. significant (p </= 0.10) nematode population reductions were obtained with the chitin-urea soil amendment in the trims on potato and walnut. in the trials on brussels sprouts and on tomato, phytotoxicity occurred at rates of 1,868 and 1,093 ... | 1992 | 19283044 |
| resistance to meloidogyne incognita race 3 and rotylenchulus reniformis in wild accessions of gossypium hirsutum and g. barbadense from mexico. | forty-six accessions of g. hirsutum and two of g. barbadense were examined for resistance to meloidogyne incognita race 3 and rotylenchulus reniformis in environmental growth chamber experiments, with the objective of finding new sources of resistance. only the g. barbadense accessions, tx-1347 and tx-1348, supported significantly less reproduction by r. reniformis than the susceptible control, deltapine 16 (usda accession sa-1186). however, they were highly susceptible to m. incognita race 3. t ... | 1997 | 19274280 |
| impact of soil texture on the reproductive and damage potentials of rotylenchulus reniformis and meloidogyne incognita on cotton. | the effects of soil type and initial inoculum density (pi) on the reproductive and damage potentials of meloidogyne incognita and rotylenchulus reniformis on cotton were evaluated in microplot experiments from 1991 to 1993. the equilibrium nematode population density for r. reniformis on cotton was much greater than that of m. incognita, indicating that cotton is a better host for r. reniformis than m. incognita. reproduction of m. incognita was greater in coarse-textured soils than in fine-text ... | 1996 | 19277171 |
| extraction of root-associated meloidogyne incognita and rotylenchulus reniformis. | a technique based on physical maceration of root tissue was developed to extract vermiform and swollen stages of meloidogyne incognita and rotylenchulus reniformis. experiments conducted on soybean and tomato evaluated the efficiency of method (stir, grind), naoc1 concentration (0%, 0.5%), and duration (lx, 2x) on extraction of nematodes and eggs from 60-day-old populations. root-associated populations of r. reniformis were considerably lower than those of m. incognita, so development of the met ... | 1997 | 19274151 |
| tolerance to rotylenchulus reniformis and resistance to meloidogyne incognita race 3 in high-yielding breeding lines of upland cotton. | field experiments in 1992 and 1994 were conducted to determine the effect of rotylenchulus reniformis, reniform nematode, on lint yield and fiber quality of 10 experimental breeding lines of cotton (gossypium hirsutum) in untreated plots or plots fumigated with 1,3-dichloropropene. controls were la. rn 1032, a germplasm line possessing some resistance to r. reniformis, and stoneville 453, a cultivar that is susceptible to reniform nematode. several breeding lines produced greater lint yields tha ... | 1997 | 19274165 |
| greenhouse evaluation of selected soybean germplasm for resistance to north carolina populations of heterodera glycines, rotylenchulus reniformis, and meloidogyne species. | selected soybean genotypes were evaluated for resistance to north carolina populations of the soybean cyst nematode heterodera glycines, the root-knot nematodes meloidogyne incognita races 3 and 4, m. arenaria races 1 and 2, m. javanica, and the reniform nematode rotylenchulus reniformis in two greenhouse tests. populations of cyst nematode used in the first test were cultures from field samples originally classified as races 1-5, and those used in the second test included inbred cyst lines that ... | 1996 | 19277179 |
| penetration of susceptible and resistant tobacco cultivars by meloidogyne juveniles. | rates of penetration of meloidogyne incognita, m. arenaria, and m. javanica into tobacco cultivars nc2326 (susceptible to all three species) and k399 (resistant to m. incognita) and a breeding line that had been selected for resistance to m. incognita were compared. meloidogyne incognita penetrated nc2326 rapidly during the first 24 hours after inoculation. numbers of m. incognita continued to increase gradually through the 14-day experiment. higher numbers of m. incognita were observed in the r ... | 1991 | 19283116 |
| interaction between meloidogyne incognita and agrobacterium tumefaciens or fusarium oxysporum f. sp. lycopersici on tomato. | agrobacterium tumefaciens stimulated and fusarium oxysporum f. sp. lycopersici inhibited development and reproduction of meloidogyne incognita when applied to the opposite split root of tomato, lycopersicon esculentum cv. tropic, plants. the lowest rate of nematode reproduction occurred after 2,000 juveniles were applied and the fungus was present in the opposite split root. the effects of all three pathogens alone on the growth of roots and shoots of tomato plants were evident, but m. incognita ... | 1991 | 19283119 |
| 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 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 |
| optimal release rates for attracting meloidogyne incognita, rotylenchulus reniformis, and other nematodes to carbon dioxide in sand. | movement of vermiform stages of meloidogyne incognita, rotylenchulus reniformis, ditylenchus phyllobius, steinernema glaseri, and caenorhabditis elegans in response to carbon dioxide was studied in 40- and 72-mm-long cylinders of moist sand inside 38-mm-d acrylic tubes. meloidogyne incognita, r. reniformis, and s. glaseri were attracted to co when placed on a linear gradient of 0.2%/cm at a mean co concentration of 1.2%. when co was delivered into the sand through a syringe needle at flow rates ... | 1995 | 19277260 |
| relationship between meloidogyne incognita and rotylenchulus reniformis as influenced by soybean genotype. | the effect of soybean genotype on competition between meloidogyne incognita race 2 (mi) and rotylenchulus reniformis (rr) was evaluated in greenhouse and microplot replacement series experiments. soil in pots containing seedlings of 'davis' (susceptible to mi) or 'buckshot 66' (resistant to mi) was infested with 1,000 vermiform individuals in the following mi:rr ratios: 0:0, 100:0, 75:25, 50:50, 25:75, or 0:100. after 91 days, the relative nematode yields (number of nematodes in mixed culture di ... | 1997 | 19274173 |
| enzymes of the phenylpropanoid pathway in soybean infected with meloidogyne incognita or heterodera glycines. | transcription of genes encoding several enzymes and the activity of some of these enzymes of the phenylpropanoid pathway leading to synthesis of chemical and physical barriers for defense of plants against root pathogens was estimated in susceptible and resistant soybean infected with heterodera glycines race 3 or with meloidogyne incognita race 3. transcription of genes encoding phenylalanine ammonia lyase (pal) and the activity of this enzyme increased in resistant, but not susceptible, soybea ... | 1995 | 19277292 |
| effect of application timing and method on efficacy and phytotoxicity of 1,3-d, chloropicrin and metam-sodium combinations in squash plasticulture. | metam-sodium, 1,3-dichloropropene (1,3-d) and chloropicrin are widely used soil fumigants. combined application of metam-sodium and 1,3-d + chloropicrin is intended to improve efficacy and broaden spectrum of control, but little is known about the effect on crop safety. this study aimed to evaluate the effects of application timing of fumigant combinations on soilborne pest and disease control (nematodes, soil fungi and weeds) and growth of squash. two separate tests with chisel-injected and dri ... | 2008 | 18181144 |
| mitochondrial dna sequence divergence among meloidogyne incognita, romanomermis culicivorax, ascaris suum, and caenorhabditis elegans. | mitochondrial dna sequences were obtained from the nadh dehydrogenase subunit 3 (nd3), large rrna, and cytochrome b genes from meloidogyne incognita and romanomermis culicivorax. both species show considerable genetic distance within these same genes when compared with caenorhabditis elegans or ascaris suum, two species previously analyzed. caenorhabditis, ascaris, and meloidogyne were selected as representatives of three subclasses in the nematode class secernentea: rhabditia, spiruria, and dip ... | 1993 | 19279810 |
| 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 |
| reduction of phytoparasitic nematodes on tomato by soil solarization and genotype. | the effects of soil solarization and tomato (lycopersicon esculentum) genotype on populations of plant-parasitic nematodes and bacterial wilt were examined in north florida. maximum soil temperatures achieved under solarization treatments using a photoselective polyethylene mulch were 49.5, 46, and 40.5 c at depths of 5, 15, and 25 cm, respectively. soil solarization reduced (p < 0.05) populations of paratrichodorus minor, rotylenchulus reniformis, and criconemella spp. 85 days after transplanti ... | 1993 | 19279843 |
| response of trifolium repens clones to infection by meloidogyne incognita and peanut stunt virus. | the responses of selected clones of white clover (trifolium repens) to simultaneous infection by the southern root-knot nematode (meloidogyne incognita) and peanut stunt virus (psv) were determined. two white clover clones, which were resistant (nc-r) or sensitive (nc-s) to ozone injury, were evaluated. plant growth and m. incognita reproduction were measured. root, stolon, and top growth were reduced by psv infection, which affected nc-r more than nc-s. both clones were tolerant of m. incognita ... | 1993 | 19279855 |
| meloidogyne incognita and rotylenchulus reniformis and associated soil textures from some cotton production areas of texas. | the incidence of meloidogyne incognita and rotylenchulus reniformis on cotton was determined in 1989-92 from 1,089 soil samples collected from 31 counties that account for nearly 60% of the 2.2 million hectares planted to cotton in texas. meloidogyne incognita was commonly found in the southern high plains and brazos river valley regions of texas (57% and 34%, respectively, of samples) but was found in less than 8% of samples from the central blacklands, coastal bend, low plains, or the upper gu ... | 1993 | 19279860 |
| effects and dynamics of a nematode community on maize. | relationships between nematode density and yield and between final and preplant population levels were examined in small maize plots on sandy soils in north-central florida. plant-parasitic nematodes present in the community included belonolaimus longicaudatus, criconemella sphaerocephala, meloidogyne incognita, paratrichodorus minor, pratylenchus brachyurus, and a xiphinema sp. plant growth--including stand count, grain yield, stalk weight, and size of young plants--often was inversely correlat ... | 1989 | 19287639 |
| movement of five nematode species through sand subjected to natural temperature gradient fluctuations. | temperature gradient fluctuations that occur naturally as a result of heating and cooling of the soil surface were reproduced within 15-cm-d, 15-cm-long acrylic tubes filled with moist sand. sunny and rainy periods during the late summer in eastern texas were simulated. five ecologically different nematode species were adapted to fluctuating temperatures for 20-36 hours at a simulated depth of 12.5 cm before being injected simultaneously into the centers of tubes at that depth. when heat waves w ... | 1994 | 19279868 |
| monoclonal antibodies to the esophageal glands and stylet secretions of heterodera glycines. | three monodonal antibodies (mabs) that bound to secretory granules within the subventral esophageal glands of second-stage juveniles (j2) of the soybean cyst nematode (scn), heterodera glycines, were developed from intrasplenic immunizations of a mouse with homogenates of scn j2. two mabs to the secretory granules within subventral glands and one mab to granules within the dorsal esophageal gland of scn j2 were developed by intrasplenic immunizations with j2 stylet secretions. stylet secretions, ... | 1994 | 19279890 |
| host response of ornamental palms to rotylenchulus reniformis. | the responses of 20 species of ornamental palms and one cycad (cycas revoluta) to two populations of the reniform nematode, rotylenchulus reniformis, from southern florida were studied in two greenhouse experiments conducted in 1989-1991 and 1991-92. ornamental palms in pots were exposed to initial population densities of 400 and 1,500 r. reniformis/l00 cm(3) soil for 16 and 15 months, respectively. nematode reproduction occurred on acoelorrhaphe wrightii and washingtonia robusta, but not on the ... | 1994 | 19279956 |
| evaluation of nicotiana otophora as a source of resistance to meloidogyne incognita race 4 for tobacco. | no currently available tobacco cultivar possesses resistance to meloidogyne incognita race 4, nor has any source of resistance been reported within nicotiana tabacum. the purpose of this study was to evaluate n. otophora acc. la quinta as a source of resistance to this pathogen. plants of tobacco cvs. nc 95 and nc 2326, n. otophora la quinta and n. repanda were inoculated with second-stage juveniles of m. incognita race 4. gall indices and egg-mass ratings were assessed at 4 and 8 weeks after in ... | 1992 | 19282991 |
| comparison of reproduction by meloidogyne graminicola and m. incognita on trifolium species. | the reproductive potential of meloidogyne graminicola was compared with that of m. incognita on trifolium species in greenhouse studies. twenty-five trifolium plant introductions, cultivars, or populations representing 23 species were evaluated for nematode reproduction and root galling 45 days after inoculation with 3,000 eggs of m. graminicola or m. incognita. root galling and egg production by the two root-knot nematode species was similar on most of the trifolium species. in a separate study ... | 1992 | 19282992 |
| spring or fall fumigation for control of meloidogyne spp. on tobacco. | tests were conducted in 1987-88 to compare the efficacy of spring or fall fumigant nematicide applications for control ofmeloidogyne arenaria and m. incognita on tobacco. chloropicrin, 1,3-d, methyl isothiocyanate, and a methyl isothiocyanate-l,3-d mixture were applied as row treatments. fenamiphos, fenamiphos + fensulfothion, or ethoprop were applied in the spring as nonfumigant nematicide standards. fumigant nematicides increased yields and reduced galling (p = 0.01) in all four tests. spring ... | 1990 | 19287773 |
| reproduction of meloidogyne incognita on open-pollinated maize varieties. | forty-three open-pollinated maize varieties were tested for resistance to the southern root-knot nematode, meloidogyne incognita race 4, in greenhouse tests. an experiment repeated on five different planting dates assessed nematode reproduction 60 days after inoculation with 3,000 eggs per plant. tebeau and old raccoon showed consistently high levels of resistance in all plantings, with the lowest reproduction factor (rf) values (0.2 and 0.4) and low numbers of eggs per gram of fresh root (222 a ... | 1990 | 19287774 |
| interaction of three plant-parasitic nematodes on corn and soybean. | interaction of belonolaimus longicaudatus, meloidogyne incognita, and pratylenchus brachyurus on corn and b. longicaudatus, m. incognita, and heterodera glycines on soybean was investigated in micropiots during two seasons for corn and one season for soybean. changes in population densities and effects on plant growth of each nematode on corn or soybean alone and in mixed culture were compared. no interactions occurred on corn in 1987. in 1988, midseason population densities of b. longicaudatus ... | 1990 | 19287797 |
| effect of temperature on attachment, development, and interactions of pasteuria penetrans on meloidogyne incognita. | the effect of temperature (10, 20, 25, 30, and 35 c) on attachment and development of pasteuria penetrans on meloidogyne arenaria race 1 was elevated in growth chambers. the greatest attachment rate of endospores of p. penetrans occurred on second-stage juveniles at 30 c. the bacterium developed more quickly within its host at 30 and 35 c than at 25 c or below. the development of the bacterium within the nematode female was divided into nine recognizable life stages, which ranged from early vege ... | 1992 | 19283029 |
| biological control of meloidogyne incognita by paecilomyces lilacinus and pasteuria penetrans. | the root-knot nematode meloidogyne incognita was controlled more effectively and yields of host plants were greater when paecilomyces lilacinus and pasteuria penetrans were applied together in field microplots than when either was applied alone. yields of winter vetch from microplots inoculated with the nematode and with both organisms were not statistically different from yields from uninoculated control plots. | 1987 | 19290133 |
| reproduction of four races of meloidogyne incognita on hibiscus cannabinus. | the feasibility of cultivation of kenaf (hibiscus cannabinus) in the united states is receiving a multifaceted evaluation. among the factors being evaluated is kenafs susceptibility to nematodes. in this investigation, four races of meloidogyne incognita reproduced extensively on each of the several kenaf genotypes examined in greenhouse tests. some genotypes of kenaf, however, demonstrated limited resistance to certain races of m. incognita. | 1992 | 19283051 |
| survey of nematodes on coffee in hawaii. | surveys of coffee fields in hawaii during 1989-1991 indicated the presence of 10 nematode species in 8 genera. after coffee was planted in fields previously in sugarcane, populations of criconemella sp. and pratylenchus zeae gradually decreased, while rotylenchulus reniformis and, in one field, meloidogyne incognita, increased in numbers. coffee is a poor host of r. reniformis, but weeds in coffee plantations may support this nematode. at present, nematodes pose no serious threat to hawaii's exp ... | 1992 | 19283060 |
| survey of plant-parasitic nematodes in missouri cotton fields. | during september 1990, 30 cotton fields in each of three missouri counties were surveyed for plant-parasitic nematodes. soil samples for nematode analysis consisted of a composite of 20 cores collected in a zig-zag pattern within a 1-ha block in each field. cores were taken from within weed-free cotton rows. nine genera of plant-parasitic nematodes were found (rotylenchulus, helicotylenchus, hoplolaimus, meloidogyne, paratylenchus, pratylenchus, tylenchorhynchus, heterodera, and trichodorus), an ... | 1992 | 19283062 |
| relationships between soil and levels of meloidogyne incognita and tobacco yield and quality. | a 2-year study with six soils and four levels of meloidogyne incognita in microplots was designed to determine the effects of these parameters on nematode activity and tobacco yield and quality. key components under study were affected by soil, nematode level, and season (year-cultivar). in 1980, low initial nematode numbers (1,250) enhanced tobacco yield in cecil clay loam, but caused slight to moderate yield losses in the other soils. yield losses to m. incognita were generally greatest in san ... | 1991 | 19283097 |
| biological control of soil pests by mixed application of entomopathogenic and fungivorous nematodes. | in greenhouse experiments, massive application of the fungivorous nematode, aphelenchus avenae, in summer at 26-33 c (1 x l0 nematodes/500 cm(3) autoclaved soil) or in autumn at 18-23 c (5 x 10 nematodes/500 cm(3) autoclaved soil) suppressed pre-emergence damping-off of cucumber seedlings due to rhizoctonia solani ag-4 by 67% or 87%, respectively. application of 2 x l0 a. avenae to sterilized soil infested with r. solani caused leafminer-like symptom on the cotyledons, which did not occur in mix ... | 1991 | 19283109 |
| stage-specific differences in lectin binding to the surface of anguina tritici and meloidogyne incognita. | the occurrence and distribution of several lectin binding sites on the outer surfaces of eggs, preparasitic second-stage juveniles (j2), parasitic second-stage juveniles (pj2), females, and males of two tylenchid nematodes, anguina tritici and meloidogyne incognita race 3, were compared. in both species, a greater variety of lectins bound to the eggs than to other life stages; lectin binding to eggs was also more intense than it was to other life stages. species-specific differences also occurre ... | 1991 | 19283123 |
| characteristics and efficacy of a sterile hyphomycete (arf18), a new biocontrol agent for heterodera glycines and other nematodes. | a filamentous, nonsporulating fungus, designated arkansas fungus 18 (arf18), was isolated from 9 of 95 populations of heterodera glycines, the soybean cyst nematode, in arkansas. in petri dishes, arf18 parasitized 89% of h. glycines eggs in cysts. the fungus also infected eggs of meloidogyne incognita and eggs in cysts of cactodera betulae, h. graminophila, h. lespedezae, h. leuceilyma, h. schachtii, and h. trifolii. in pot tests, reproduction of scn was 70% less in untreated field soil that was ... | 1991 | 19283127 |
| yield-loss models for tobacco infected with meloidogyne incognita as affected by soil moisture. | yield-loss models were developed for tobacco infected with meloidogyne incognita grown in microplots under various irrigation regimes. the rate of relative yield loss per initial nematode density (pi), where relative yield is a proportion of the value of the harvested leaves in uninfected plants with the same irrigation treatment, was greater under conditions of water stress or with high irrigation than at an intermediate level of soil moisture. the maximum rate of plant growth per degree-day (b ... | 1991 | 19283140 |
| resistance in soybean cultivars from maturity groups v-viii to soybean cyst and root-knot nematodes. | one hundred thirty-nine cultivars of soybean (glycine max) in maturity groups v, vi, vii, and viii were evaluated in a greenhouse for resistance to heterodera glycines races 3 and 14 and meloidogyne incognita, m. arenaria, and m. javanica. of the cultivars tested, 37% had resistance to h. glycines race 3 alone, 12% had resistance to both races 3 and 14, and 69% exhibited a moderate or high level of resistance to one or more of the meloidogyne spp. however, 24% were susceptible to each race of h. ... | 1991 | 19283166 |
| 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 |
| suppression of meloidogyne incognita and m. javanica by pasteuria penetrans in field soil. | the role of pasteuria penetrans in suppressing numbers of root-knot nematodes was investigated in a 7-year monocuhure of tobacco in a field naturally infested with a mixed population of meloidogyne incognita race 1 and m. javanica. the suppressiveness of the soil was tested using four treatments: autoclaving (ac), microwaving (mw), air drying (dr), and untreated. the treated soil bioassays consisted of tobacco cv. northrup king 326 (resistant to m. incognita but susceptible to m. javanica) and c ... | 1996 | 19277344 |
| growth of isolates of paecilomyces lilacinus and their efficacy in biocontrol of meloidogyne incognita on tomato. | the potential of 13 paecilomyces lilacinus isolates from various geographic regions as biocontrol agents against meloidogyne incognita, the effects of temperature on their growth, and the characterization of the impact of soil temperature on their efficacy for controlling this nematode were investigated. maximum fungal growth, as determined by dry weight of the mycelium, occurred from 24 to 30 c; least growth was at 12 and 36 c. the best control of m. incognita was provided by an isolate from pe ... | 1989 | 19287594 |
| influence of four nematodes on root and shoot growth parameters in grape. | two grape cultivars, susceptible french colombard and tolerant rubired, and four nematodes, meloidogyne incognita, pratylenchus vulnus, tylenchulus semipenetrans, and xiphinema index, were used to quantify the equilibrium between root (r) and shoot (s) growth. root and shoot growth of french colombard was retarded by m. incognita, p. vulnus, and x. index but not by t. semipenetrans. although the root growth of rubired was limited by all the nematodes, the shoot growth was limited only by x. inde ... | 1989 | 19287609 |
| accelerated movement of nematodes from soil in baermann funnels with temperature gradients. | baermann funnels were modified to eliminate or reverse the small temperature gradient (1-2 c/cm) across the soil layer that normally results from water evaporation. effects of modifications on extraction efficiency were examined at various ambient temperatures and after overnight adaptation of three nematode species at 20 and 30 c. extraction of meloidogyne incognita from sandy loam, tylenchulus semipenetrans from sandy clay loam, and rotylenchulus reniformis from silt was greatly accelerated si ... | 1989 | 19287622 |
| monoclonal antibodies to secretory granules in esophageal glands of meloidogyne species. | monoclonal antibodies to secretory granules in the dorsal or subventral esophageal glands were generated by injecting balb/c mice with immunogens from preparasitic second-stage juveniles (j2) of meloidogyne incognita. antibodies specific for secretory granules in the j2 subventral esophageal glands or the dorsal gland were identified by indirect immunofluorescence microscopy. only antibodies that reacted with granules in the j2 dorsal gland reacted with the esophageal gland lobe ofm. incognita a ... | 1989 | 19287625 |
| tillage and multiple cropping systems and population dynamics of phytoparasitic nematodes. | the effect of two cropping and tillage systems on the population dynamics of four nematode species was evaluated on a loamy sand. hairy vetch succeeded by corn or grain sorghum was seeded in split plots randomized within whole plots of no-tillage versus conventional tillage over four growing seasons (1980-83). the vetch-corn cropping system increased the density of meloidogyne incognita 2.9 x more than the vetch-grain sorghum cropping system. in contrast, the vetch-grain sorghum cropping system ... | 1988 | 19290311 |
| effects and dynamics of a nematode community on soybean. | the relationships between densities of all members of a plant-parasitic nematode community and yield of 'davis' soybean and between final and preplant population levels were examined in small plots on sandy soils in north-central florida. plant-parasitic nematodes present in the community included belonolaimus longicaudatus, criconemella sphaerocephala, meloidogyne incognita, paratrichodorus minor, pratylenchus brachyurus, and xiphinema sp. plant growth, including stand count, soybean yield (kg/ ... | 1989 | 19287643 |
| potential of crops uncommon to alabama for management of root-knot and soybean cyst nematodes. | vigna unguiculata, cassia fasiculata, and sesamum indicum did not support meloidogyne arenaria, m. incognita, or heterodera glycines race 4 in greenhouse studies with soils from peanut and soybean fields. fagopyron eseulentum, cyamopsis tetragonoloba, and cucurbita pepo were hosts to the two meloidogyne spp. but were nonhosts to h. glycines. meloidogyne arenaria and m. incognita galled but reproduced poorly in the roots of three types of amaranthus cruentus, and low densities of these two meloid ... | 1988 | 19290317 |
| managing root-knot on tobacco in the southeastern united states. | root-knot nematodes suppress yields of flue-cured tobacco an estimated 0.1 to 4.8% annually in the southeastern united states, even though nematode management practices have been widely adopted. although meloidogyne incognita races 1 and 3 have predominated, m. arenaria, m. javanica, and m. incognita races 2 and 4 are increasingly important. seventy-five percent of the flue-cured tobacco hectarage in north carolina and virginia is rotated on 2-year or 3-year intervals. over half of the hectarage ... | 1989 | 19287655 |
| vertical distribution of plant-parasitic nematodes in sandy soil under soybean. | vertical distribution of five plant-parasitic nematodes was examined in two north florida soybean fields in 1987 and 1988. soil samples were collected from 0-15 cm, 15-30 cm, and 30-45 cm deep at each site. soil at the three depths consisted of approximately 96% sand. more than 50% of belonolaimus longicaudatus population densities occurred in the upper 15-cm soil layer at planting, but the species became more evenly distributed through the other depths as the season progressed. criconemella sph ... | 1990 | 19287693 |
| meloidogyne incognita survival in soil infested with paecilomyces lilacinus and verticillium chlamydosporium. | meloidogyne incognita-infected tomato seedlings were transplanted into sterilized soil or unsterilized soil collected from 20 california tomato fields to measure suppression caused by paecilomyces lilacinus, verticillium chlamydosporium, and other naturally occurring antagonists. unsterilized soils q, a, and h contained 35, 39, and 55% fewer m. incognita second-stage juveniles (j2) than did sterilized soil 1 month after infected tomato seedlings were transplanted to these soils and placed in a g ... | 1990 | 19287707 |
| overestimation of yield loss of tobacco caused by the aggregated spatial pattern of meloidogyne incognita. | overestimation of yield loss caused by meloidogyne incognita on tobacco was calculated as a function of the statistical frequency distribution of sample counts. sampling frequency distributions were described by a negative binomial model, with parameter k, and the resulting probability generating function was used to calculate discrete damage probabilities. negative binomial damage predictions were compared to mean-density estimates of damage. predictions based on mean density alone overestimate ... | 1985 | 19294089 |
| association of verticillium chlamydosporium and paecilomyces lilacinus with root-knot nematode infested soil. | population densities of meloidogyne incognita and the nematophagous fungi, paecilomyces lilacinus and verticillium chlamydosporium, were determined in 20 northern california tomato fields over two growing seasons. paecilomyces lilacinus was isolated from three fields, v. chlamydosporium was isolated from one field, and both fungi were isolated from 12 fields. verticillium chlamydosporium numbers were positively correlated with numbers of m. incognita and p. lilacinus. paecilomyces lilacinus numb ... | 1990 | 19287711 |
| nicotine content of tobacco roots and toxicity to meloidogyne incognita. | the motility of meloidogyne incognita second-stage juveniles (j2) and their ability to induce root galls in tomato were progressively decreased upon exposure to nicotine at concentrations of 1-100 mug/ml. ec values ranged from 14.5 to 22.3 mug/ml, but j2 motility and root-gall induction were not eliminated at 100 mug/ml nicotine. nicotine in both resistant nc 89 and susceptible nc 2326 tobacco roots was increased significantly 4 days after exposure to m. incognita. the increase was greater in re ... | 1987 | 19290102 |
| interaction between meloidogyne incognita and hoplolaimus columbus on davis soybean. | greenhouse and laboratory experiments were performed to determine if an interaction exists between meloidogyne incognita and hoplolaimus columbus on davis soybean. greenhouse tests were performed with three population levels of m. incognita and h. columbus (0, 1,500, 6,000/1.5-liter pot) separately and in all combinations. dry root weight (drt) declined nonlinearly and dry shoot weight (dst) declined linearly with respect to increasing initial populations of m. incognita and h. columbus. when th ... | 1987 | 19290154 |
| selective migration and root penetration by meloidogyne incognita and hoplolaimus columbus on soybean roots in vitro. | | 1987 | 19290161 |
| interactions between meloidogyne incognita and pratylenchus brachyurus on soybean. | interactions among meloidogyne incognita, pratylenchus brachyurus, and soybean genotype on plant growth and nematode reproduction were studied in a greenhouse. coker 317 (susceptible to both nematodes) and gordon (resistant to m. incognita, susceptible to p. brachyurus) were inoculated with increasing initial population densities (pi) of both nematodes individually and combined. m. incognita and p. brachyurus individually usually suppressed shoot growth of both cultivars, but only root growth on ... | 1988 | 19290187 |
| histology of the interactions of paecilomyces lilacinus with meloidogyne incognita on tomato. | excised tomato roots were examined histologically for interactions of the fungus paecilomyces lilacinus and meloidogyne incognita race 1. root galling and giant-cell formation were absent in tomato roots inoculated with nematode eggs infected with p. lilacinus. few to no galls and no giant-cell formation were found in roots dipped in a spore suspension of p. lilacinus and inoculated with m. incognita. numerous large galls and giant cells were present in roots inoculated only with m. incognita. p ... | 1988 | 19290224 |
| application of isoelectric focusing to the taxonomic identification of meloidogyne spp. | meloidogyne incognita, m. arenaria, m. hapla, and m. javanica were distinguishable from each other by isoelectric focusing (ief) of nematode egg proteins. proteins extracted from larvae and adults of hoplolaimus columbus and from eggs of heterodera glycines had distinctive profiles, also. protein profiles from eggs, preparasitic larvae and egg-laying adults of m. incognita showed differences. it was necessary to compare samples run at the same time to ensure reliability. | 1984 | 19295881 |