| qtl mapping for resistance to root-knot nematodes in the m-120 rnr upland cotton line (gossypium hirsutum l.) of the auburn 623 rnr source. | root-knot nematodes meloidogyne incognita (kofoid and white) can cause severe yield loss in cotton (gossypium hirsutum l.). the objectives of this study were to determine the inheritance and genomic location of genes conferring root-knot nematode resistance in m-120 rnr, a highly resistant g. hirsutum line with the auburn 623 rnr source of resistance. utilizing two interspecific f(2) populations developed from the same m-120 rnr by gossypium barbadense (cv. pima s-6) cross, genome-wide scanning ... | 2006 | 16960714 |
| phenotypic expression of rkn1-mediated meloidogyne incognita resistance in gossypium hirsutum populations. | the root-knot nematode meloidogyne incognita is a damaging pest of cotton (gossypium hirsutum) worldwide. a major gene (rkn1) conferring resistance to m. incognita was previously identified on linkage group a03 in g. hirsutum cv. acala nemx. to determine the patterns of segregation and phenotypic expression of rkn1, f(1), f(2), f(2:3), bc(1)f(1) and f(2:7) recombinant inbred lines (ril) from intraspecific crosses between acala nemx and a closely related susceptible cultivar acala sj-2 were inocu ... | 2006 | 19259455 |
| a symbiont-independent endo-1,4-beta-xylanase from the plant-parasitic nematode meloidogyne incognita. | substituted xylan polymers constitute a major part of the hemicellulose fraction of plant cell walls, especially in monocotyledons. endo-1,4-beta-xylanases (ec 3.2.1.8) are capable of hydrolyzing substituted xylan polymers into fragments of random size. many herbivorous animals have evolved intimate relationships with endosymbionts to exploit their enzyme complexes for the degradation of xylan. here, we report the first finding of a functional endo-1,4-beta-xylanase gene from an animal. the gene ... | 2006 | 16673939 |
| root-knot nematode management in double-cropped plasticulture vegetables. | combination treatments of chisel-injected fumigants (methyl bromide, 1,3-d, metam sodium, and chloropicrin) on a first crop, followed by drip-applied fumigants (metam sodium and 1,3-d +/- chloropicrin) on a second crop, with and without oxamyl drip applications were evaluated for control of meloidogyne incognita in three different tests (2002 to 2004) in tifton, ga. first crops were eggplant or tomato, and second crops were cantaloupe, squash, or jalapeno pepper. double-cropped vegetables suffer ... | 2006 | 19259431 |
| screening of field pea (pisum sativum) selections for their reactions to root-knot nematode (meloidogyne incognita). | pot studies were carried out to evaluate the reactions of 23 selections of field pea (pisum sativum) against meloidogyne incognita (2000 freshly hatched juveniles (j2)/pot). experiment was conducted under greenhouse conditions ((24.7+/-3) degrees c and (62+/-7)% rh) and terminated 45 d after inoculation. the roots of all the selections were assessed to determine root-knot indices (rki) on a 0-4 scale. out of 23 selections hfp-990713, pant p-25, and hfp-0129 were resistant; pant p-2005, ndp-2 and ... | 2006 | 16502508 |
| in planta secretion of a calreticulin by migratory and sedentary stages of root-knot nematode. | esophageal secretions from endoparasitic sedentary nematodes are thought to play key roles throughout plant parasitism, in particular during the invasion of the root tissue and the initiation and maintenance of the nematode feeding site (nfs) essential for nematode development. the secretion in planta of esophageal cell-wall-degrading enzymes by migratory juveniles has been shown, suggesting a role for these enzymes in the invasion phase. nevertheless, the secretion of an esophageal gland protei ... | 2005 | 16478047 |
| identification and mapping of microsatellite markers linked to a root-knot nematode resistance gene (rkn1) in acala nemx cotton (gossypium hirsutum l.). | host-plant resistance is the most economic and effective strategy for root-knot nematode (rkn) meloidogyne incognita control in cotton (gossypium hirsutum l.). molecular markers linked to resistance are important for incorporating resistance genes into elite cultivars. to screen for microsatellite markers (ssr) closely linked to rkn resistance in g. hirsutum cv. acala nemx, f1, f2, bc1f1, and f2:7 recombinant inbred lines (rils) from intraspecific crosses and an f2 from an interspecific cross wi ... | 2006 | 16362274 |
| a method for field infestation with meloidogyne incognita. | a field inoculation method was developed to produce meloidogyne spp. infestation sites with minimal quantities of nematode inoculum and with a reduced labor requirement compared to previous techniques. in a preseason-methyl bromidefumigated site, nematode egg suspensions were delivered at concentrations of 0 or 10(x) eggs/m of row where x = 2.12, 2.82, 3.52, or 4.22 through a drip line attached to the seed firmer of a commercial 2-row planter into the open seed furrow while planting cowpea. thes ... | 2005 | 19262898 |
| fitness of virulent meloidogyne incognita isolates on susceptible and resistant cowpea. | a study of life-history traits was made to determine factors associated with the fitness of meloidogyne incognita isolates virulent to resistance gene rk in cowpea. egg hatch, root penetration, egg mass production, and fecundity (eggs per egg mass) of avirulent and virulent phenotypes were compared among m. incognita isolates, isofemale lines, and single descent lines over multiple generations on resistant and susceptible cowpea. variation (p </= 0.05) in both hatch and root penetration rates wa ... | 2005 | 19262891 |
| isofemale line analysis of meloidogyne incognita virulence to cowpea resistance gene rk. | isofemale lines (ifl) from single egg masses were studied for genetic variation in meloidogyne incognita isolates avirulent and virulent to the resistance gene rk in cowpea (vigna unguiculata). in parental isolates cultured on susceptible and resistant cowpea, the virulent isolate contained 100% and the avirulent isolate 7% virulent lineages. virulence was selected from the avirulent isolate within eight generations on resistant cowpea (lineage selection). in addition, virulence was selected fro ... | 2005 | 19262890 |
| use of cucumis metuliferus as a rootstock for melon to manage meloidogyne incognita. | root-knot nematode-susceptible melons (cantaloupe) were grown in pots with varying levels of meloidogyne incognita and were compared to susceptible melons that were grafted onto cucumis metuliferus or cucurbita moschata rootstocks. in addition, the effect of using melons as transplants in nematode-infested soil was compared to direct seeding of melons in nematode-infested soil. there were no differences in shoot or root weight, or severity of root galling between transplanted and direct-seeded n ... | 2005 | 19262873 |
| application of rna interference to root-knot nematode genes encoding esophageal gland proteins. | plant parasitic nematodes have been, so far, refractory to transformation or mutagenesis. the functional analysis of nematode genes relies on the development of reverse genetic tools adapted to these obligate parasites. here, we describe the application of rna interference (rnai) to the root-knot nematode meloidogyne incognita for the knock-down of two genes expressed in the subventral esophageal glands of the nematode and potentially involved in parasitism, the calreticulin (mi-crt) and the pol ... | 2005 | 16042006 |
| nematicidal natural products from the aerial parts of lantana camara linn. | lantanilic acid, camaric acid and oleanolic acid possessing nematicidal activity were isolated from the methanolic extract of the aerial parts of lantana camara linn. through bio-assay guided fractionation. these compounds exhibited 98%, 95% and 70% mortality respectively against root-knot nematode meloidogyne incognita at 0.5% concentration. conventional nematicide furadan showed 100% mortality at this concentration. | 2005 | 16010828 |
| isolation and characterization of a cdna encoding a serine proteinase from the root-knot nematode meloidogyne incognita. | this report describes the first serine proteinase gene isolated from the sedentary nematode meloidogyne incognita. using degenerate primers, a 1372bp cdna encoding a chymotrypsin-like serine proteinase (mi-ser1) was amplified from total rna of adult females by rt-pcr and 5' and 3' rapid amplification of cdna ends. the deduced amino acid sequence of mi-ser1 encoded a putative signal peptide and a prodomain of 22 and 33 amino acids, respectively, and a mature proteinase of 341 amino acids with a p ... | 2005 | 15888294 |
| developmental expression and molecular analysis of two meloidogyne incognita pectate lyase genes. | proteinaceous secretions from the oesophageal glands of plant-parasitic nematodes have crucial roles in nematode parasitism of plants. two cdnas (designated mi-pel-1 and mi-pel-2) encoding pectate lyases were isolated from the root-knot nematode, meloidogyne incognita, oesophageal gland-cell subtractive cdna libraries, and the corresponding genomic dnas were subsequently cloned. southern blot analyses revealed that homologues to these pectate lyase genes were broadly distributed in meloidogyne s ... | 2005 | 15862581 |
| effect of tea dust residues to control root-knot nematode of tomato. | in this research, control of tomato root- knot nematode (meloidogyne incognita) was conducted using tea dust residues at different rates. first, the species and race of nematode were identified by employing diagnostic keys. then, with 5 replications in complete randomized design. tea dust residues were used at 9 treatments (0, 5, 10, 15, 20, 25, 30, 35 and 40 g/kg of soil). statistical analysis on mean treatments rates showed that treatment with 25 g/kg soil economically was effective in growth ... | 2004 | 15759440 |
| resistance gene analogue markers are mapped to homeologous chromosomes in cultivated tetraploid cotton. | degenerate primers designed from conserved motifs of known plant resistance gene products were used to amplify genomic dna sequences from the root-knot nematode (meloidogyne incognita) resistance genetic source, upland cotton (gossypium hirsutum) cultivar auburn 634 rnr. a total of 165 clones were isolated, and sequence analysis revealed 57 of the clones to be novel nucleotide sequences, many containing the resistance (r)-protein nucleotide-binding site motif. a cluster analysis was performed wi ... | 2005 | 15726317 |
| an sxp/ral-2 protein produced by the subventral pharyngeal glands in the plant parasitic root-knot nematode meloidogyne incognita. | meloidogyne incognita is a major parasite of numerous plant families, including many crop species. upon infection of the plant root, it induces several multinucleate giant cells by the injection of pharyngeal gland secretions into the root cells. in order to obtain a better understanding of the nematode-plant interaction, characterization of the pharyngeal gland secretions is a necessity. by differential display, a nematode gene was identified that encodes a new member of the sxp/ral-2 protein f ... | 2005 | 15565464 |
| effects of glucosinolates and their enzymatic hydrolysis products via myrosinase on the root-knot nematode meloidogyne incognita (kofoid et white) chitw. | the root-knot nematode meloidogyne incognita (kofoid et white) chitw. is responsible for large yield losses in several horticultural crops. fumigation with chemicals has been efficient in fighting this soil pest, but it clearly shows a negative environmental impact. thus, it is necessary to find an environmentally friendly alternative to control this nematode and meet the requirements imposed by world regulation to ban some chemical fumigants in the world after 2005. the glucosinolate-myrosinase ... | 2004 | 15506804 |
| biochemical changes in glomus fasciculatum colonized roots of lycopersicon esculentum in presence of meloidogyne incognita. | glasshouse experiments were conducted to elicit biochemical substantiation for the observed difference in resistance to nematode infection in roots colonized by mycorrhiza, and susceptibility of the fresh flush of roots of the same plant that escaped mycorrhizal colonization. tomato roots were assayed for their biochemical profiles with respect to total proteins, total phenols, indole acetic acid, activities of polyphenol oxidase, phenylalanine ammonia lyase and indole acetic acid oxidase. the r ... | 2004 | 15339037 |
| effect of crotalaria juncea amendment on squash infected with meloidogyne incognita. | two greenhouse experiments were conducted to examine the effect of crotalaria juncea amendment on meloidogyne incognita population levels and growth of yellow squash (cucurbita pepo). in the first experiment, four soils with a long history of receiving yard waste compost (ywc+), no-yard-waste compost (ywc-), conventional tillage, or no-tillage treatments were used; in the second experiment, only one recently cultivated soil was used. half of the amount of each soil received air-dried residues of ... | 2004 | 19262819 |
| isolation and characterization of pra1, a trypsin-like protease from the biocontrol agent trichoderma harzianum cect 2413 displaying nematicidal activity. | mycoparasitic trichoderma strains secrete a complex set of hydrolytic enzymes under conditions related to antagonism. several proteins with proteolytic activity were detected in culture filtrates from t. harzianum cect 2413 grown in fungal cell walls or chitin and the protein responsible for the main activity (pra1) was purified to homogeneity. the enzyme was monomeric, its estimated molecular mass was 28 kda (sds-page), and its isoelectric point 4.7-4.9. the substrate specificity and inhibition ... | 2004 | 15221228 |
| pepper rootstock graft compatibility and response to meloidogyne javanica and m. incognita. | resistance of pepper species (capsicum annuum, c. baccatum, c. chinense, c. chacoense, and c. frutescens), cultivars and accessions to the root-knot nematodes meloidogyne incognita race 2 and m. javanica, and their graft compatibility with commercial pepper varieties as rootstocks were evaluated in growth chamber and greenhouse experiments. most of the plants tested were highly resistant to m. javanica but susceptible to m. incognita. capsicum annuum ar-96023 and c. frutescens accessions as root ... | 2004 | 19262798 |
| cyperus tubers protect meloidogyne incognita from 1,3-dichloropropene. | meloidogyne incognita-infected and noninfected tubers of yellow nutsedge (cyperus esculentus) and purple nutsedge (cyperus rotundus) were treated with 56 l/ha 1,3-dichloropropene (1,3-d) in microplots and subsequently examined for tuber and nematode viability in the greenhouse using a chile pepper (capsicum annuum) bioassay system. the study was conducted three times. nutsedge tuber viability and m. incognita harbored in both yellow and purple nutsedge tubers were unaffected by 1,3-d treatment. ... | 2004 | 19262797 |
| the use of olive mill wastes for the control of root-knot nematodes. | the suppressive effect of olive mill wastes was tested in a field experiment in sandy soil, infested by meloidogyne incognita, in the province of lecce, southern italy. the field was subdivided in 12 m2 plots distributed at random in four blocks. treatment consisted of different dosages (10, 20 and 40 t/ha) of two composts prepared with either exhausted or fresh olive pomace or raw extraction sewage at rate of 40 or 80 m3/ha. there were four untreated control plots and four plots on which the gr ... | 2003 | 15149102 |
| use of solid-phase subtractive hybridization for the identification of parasitism gene candidates from the root-knot nematode meloidogyne incognita. | summary a solid-phase subtractive strategy was used to clone parasitism gene candidates (pgcs) expressed in the oesophageal gland cells of meloidogyne incognita. nematode intestinal first-strand cdna was synthesized directly on magnetic beads and used to enrich for gland-specific sequences by high stringency hybridization to gland-cell mrna. a gland-specific cdna library was created from the nonhybridizing gland-cell mrna by long-distance reverse transcription polymerase chain reaction. subtract ... | 2004 | 20565611 |
| [interaction between structure of plant steroids and their effect on phytonematodes]. | the effects of certain plant steroids of the groups of furostanol glycosides, glycoalkaloids, and alpha-ecdysone on growth and development of phytoparasitic nematodes were studied. it was shown using an experimental system including tomato, lycopersicon esculentum mill., and root-knot nematode, meloidogyne incognita kofoid et white, that steroid molecule had significant nematicidic activity if it contained a carbohydrate moiety and an additional heterocycle in the steroid core. the maximum nemat ... | 2006 | 15029710 |
| reproduction of mi-virulent meloidogyne incognita isolates on lycopersicon spp. | selection of detectable numbers of mi-virulent root-knot nematodes has necessitated a greater understanding of nematode responses to new sources of resistance. during the course of this research, we compared the reproduction of four geographically distinct mi-virulent root-knot nematode isolates on three resistant accessions of lycopersicon peruvianum. each accession carried a different resistant gene, mi-3, mi-7, or mi-8. all nematode isolates were verified as meloidogyne incognita using diagno ... | 2004 | 19262789 |
| evaluation of asteraceae plants for control of meloidogyne incognita. | of the 56 species and 43 genera of asteraceae tested, 9 were highly resistant or immune to meloidogyne incognita and did not form root galls. twenty-six species and six cultivars had 25% or fewer roots galled and were considered moderately resistant to m. incognita. pre-planting cosmos bipinnatus (f190), gaillardia pulchella, tagetes erecta, tithonia diversifolia, or zinnia elegans (f645) reduced root galling and m. incognita j2 in and around ipomoea reptans. amendment of soils with roots, stems ... | 2004 | 19262785 |
| [photosynthetic pigments of tomato under conditions of biotic stress and effects of furostanol glycosides]. | adaptogenic effect of furostanol glycosides (fg) on biosynthesis of photosynthetic pigments in tomato plants (lycopersicon esculentum mill.) were studied under conditions of biotic stress caused by root-knot nematode (meloidogyne incognita kofoid et white). treatment of plants with 5 x 10(-4) m fg was accompanied by an increase in the rate of biosynthesis of pigments (particularly, chlorophyll b and carotenoids), which was observed against the background of a decrease in the relative contributio ... | 2013 | 14714485 |
| a set of genes differentially expressed between avirulent and virulent meloidogyne incognita near-isogenic lines encode secreted proteins. | a cdna-amplification fragment length polymorphism (aflp)-based strategy has been used to identify genes differentially expressed between two pairs of near-isogenic lines (nil) of the root-knot nematode meloidogyne incognita either avirulent or virulent against the tomato mi resistance gene. gene expression profiles from infective second-stage juveniles (j2) were compared, and 22 of the 24,025 transcript-derived fragments (tdf) generated proved to be differential, i.e., present in both avirulent ... | 2003 | 14651341 |
| induction of tolerance to root-knot nematode by oxycom. | oxycom applications increased plant growth and population levels of meloidogyne incognita on susceptible tomato. a single oxycom drench at 2,500 ppm applied 7 days prior to inoculation with m. incognita provided remediation of plant growth measured 63 days later. this occurred without reducing nematode population levels. follow-up drenches at 2,500 ppm at 10-day intervals stunted shoots and roots (p = 0.05). the same application rates at 20-day intervals did not reduce plant growth. plants recei ... | 2003 | 19262766 |
| pr proteins in plants infested with the root-knot nematode meloidogyne incognita (kofoid et white, 1919) chitwood 1949. | | 2016 | 12918384 |
| a profile of putative parasitism genes expressed in the esophageal gland cells of the root-knot nematode meloidogyne incognita. | identifying parasitism genes encoding proteins secreted from a nematode's esophageal gland cells and injected through its stylet into plant tissue is the key to understanding the molecular basis of nematode parasitism of plants. meloidogyne incognita parasitism genes were cloned by microaspirating the cytoplasm from the esophageal gland cells of different parasitic stages to provide mrna to create a gland cell-specific cdna library by long-distance reverse-transcriptase polymerase chain reaction ... | 2003 | 12744507 |
| management of root-knot nematode in tomato lycopersicon esculentum, mill, with biogas slurry. | the effect of biogas slurry application on the severity of root-knot nematode, meloidogyne incognita, attack on tomato cv. co-1, was tested in the green house with two levels of biogas slurry: 5% and 10% (w/w) added to soil. both the number (3 fruits/plant) and fruit yield (35.2 g/plant) of tomato increased significantly with 10% (w/w) biogas slurry. the plants amended with biogas slurry put up more vegetative growth and tended to flower and fruit much earlier than did those of the control. the ... | 2003 | 12699936 |
| relationship of aerial broad band reflectance to meloidogyne incognita density in cotton. | aerial images were obtained on 22 july 1999 and 4 august 2000 from five cotton sites infested with meloidogyne incognita. images contained three broad bands representing the green (500-600 nm), red (600-700 nm), and near-infrared (700-900 nm) spectrum. soil samples were collected and assayed for nematodes in the fall at these sites. sampling locations were identified from images, by locating the coordinates of a wide range of light intensity (measured as a digital number) for each single band, a ... | 2003 | 19265974 |
| arabidopsis thaliana mutants with an altered susceptibility to the root-knot nematode meloidogyne incognita. | sedentary endoparasitic nematodes of plants are obligate parasites of roots in which they complete their sophisticated life cycle. to study the plant/root-knot nematode interaction, a screening was performed for mutants of arabidopsis thaliana that were less susceptible to nematode infection. ethyl methanesulfonate-mutagenized a. thaliana m2 seeds (13,000) were germinated and the seedlings were screened in vitro for nematode susceptibility. another 5,000 plants were screened in a sand mixture un ... | 2002 | 12491969 |
| non-traditional legumes as potential soil amendments for nematode control. | dried ground plant tissues from 20 leguminous species were mixed with meloidogyne incognita-infested soil at 1, 2 or 2.5, and 5% (w/w) and incubated for 1 week at room temperature (21 to 27 degrees c). tomato ('rutgers') seedlings were transplanted into infested soil to determine nematode viability. most tissues reduced gall numbers below the non-amended controls. the tissue amendments that were most effective include: canavalia ensiformis, crotalaria retusa, indigofera hirsuta, i. nummularifoli ... | 2002 | 19265956 |
| red food coloring stain: new, safer procedures for staining nematodes in roots and egg masses on root surfaces. | acid fuchsin and phloxine b are commonly used to stain plant-parasitic nematodes in roots and egg masses on root surfaces, respectively. both stains can be harmful to both the user and the environment and require costly waste disposal procedures. we developed safer methods to replace both stains using mccormick schilling red food color. eggs, juveniles, and adults of meloidogyne incognita stained in roots with red food color were equally as visible as those stained with acid fuchsin. egg masses ... | 2002 | 19265929 |
| effects of site-specific application of aldicarb on cotton in a meloidogyne incognita-infested field. | cotton farmers in missouri commonly apply a single rate of aldicarb throughout the field at planting to protect their crop from meloidogyne incognita, even though these nematodes are spatially aggregated. our purpose was to determine the effect of site-specific application of aldicarb on cotton production in a field infested with these nematodes in 1997 and 1998. cotton yields were collected from sites not treated with aldicarb (control), sites receiving aldicarb at the standard recommended rate ... | 2002 | 19265917 |
| [investigation on root-knot diseases of medicinal plants in yunnan]. | during 1994-1997, the damage levels about root-knot diseases on 52 medicinal plants were investigated and analyzed. 185 samples were collected from more than 20 counties or cities in yunnan province. the results showed that 76 specimens were infected by root-knot nematode, which are meloidogyne incognita (kofoid and white 1919, chitwood 1949), m. javanice (trenb 1855, chitwood 1949), m. arenaria (neal 1889, chitwood 1949) and m. halpa (chitwood 1949). they infected 21 medicinal plants. the paper ... | 2001 | 11917839 |
| efficacy of 1,3-dichloropropene in soil amended with compost and unamended soil. | 1,3-dichloropropene (1,3-d) is a likely alternative soil fumigant for methyl bromide. the objective was to determine root-knot nematode, meloidogyne incognita, survival in microplots after exposure to 1,3-d for various periods of time in soil that have previously been amended with compost. the treatments were 1,3-d applied broadcast at 112 liters/ha and untreated controls in both compost-amended and unamended soil. soil samples were collected from each microplot at 6, 24, 48, 72, and 96 hours af ... | 2001 | 19265889 |
| pesticidal properties of parthenin (from parthenium hysterophorus) and related compounds. | eleven sesquiterpene lactone derivatives of parthenin (1), obtained from wild feverfew, parthenium hysterophorus, were prepared by chemical and photochemical transformations. the compounds tested were a pyrazoline adduct (2) of parthenin, its cyclopropyl (3) and propenyl (4) derivatives, anhydroparthenin (5), a dihydro-deoxygenated product (6), a formate (7) and its corresponding alcohol (8) and acetate (9), a rearranged product (10), lactone (11) and hemiacetal (12). all these derivatives, alon ... | 2001 | 11455638 |
| genes induced during early response to meloidogyne incognita in roots of resistant and susceptible alfalfa cultivars. | a cdna library made to rna from roots of meloidogyne incognita (root-knot nematode) susceptible alfalfa cv. lahontan seedlings 72 h after root-knot nematode inoculation was differentially screened with cdna made from uninoculated control and m. incognita infested (72 h) root rna. of the six cdnas isolated, the deduced amino acid sequences of four showed significant homology to sequences present in the databank, while two were pioneer sequences. the four cdnas with matches to known sequences incl ... | 2001 | 11448760 |
| [modulation of plant resistance to diseases by water-soluble chitosan]. | low-molecular-weight water-soluble chitosan with a molecular weight of 5 kda obtained after enzymatic hydrolysis of native crab chitosan was shown to display an elicitor activity by inducing the local and systemic resistance of solanumi tuberosum potato and lycopesicon esculentum tomato to phytophthora infestans and nematodes, respectively. chitosan induced the accumulation of phytoalexins in tissues of host plants, decreased the total content and changed the composition of free sterols producin ... | 2013 | 11234398 |
| molecular cloning of a cdna encoding an amphid-secreted putative avirulence protein from the root-knot nematode meloidogyne incognita. | amplified fragment length polymorphism fingerprinting of three pairs of meloidogyne incognita near-isogenic lines (nils) was used to identify markers differential between nematode genotypes avirulent or virulent against the tomato mi resistance gene. one of these sequences, present only in the avirulent lines, was used as a probe to screen a cdna library from second-stage juveniles (j2s) and allowed cloning of a cdna encoding a secretory protein. the putative full-length cdna, named map-1, encod ... | 2001 | 11194874 |
| effects of meloidogyne incognita on growth and storage-root formation of cassava (manihot esculenta). | two-node cuttings of cassava cultivar ss4 were inoculated with 1,000 infective juveniles of meloidogyne incognita at 1, 14, 40, 70, 88, and 127 days after planting (dap). plant growth and root damage were assessed at 150 dap. meloidogyne incognita significantly reduced the number of storageroots formed in plants inoculated at 14, 40, 70, and 88 dap and the total weight of storage-roots in plants inoculated at 1, 14, 40, 70, and 88 dap, compared to uninoculated plants. individual storage-root wei ... | 2000 | 19270997 |
| heat stability of resistance to meloidogyne incognita in scotch bonnet peppers ( capsicum chinense jacq.). | stability of resistance to meloidogyne incognita (kofoid &white) chitwood was determined in pepper (capsicum chinense jacq. and c. annuum l.) at 24, 28, and 32 degrees c. reactions of the c. annuum cultivars charleston belle and keystone resistant giant and the c. chinense cultigens pa-426 and pa-350 to m. incognita were compared. charleston belle is homozygous for the n gene that confers resistance to m. incognita in c. annuum, and keystone resistant giant is the susceptible recurrent parent of ... | 2000 | 19270989 |
| using microwave irradiation to improve preservation of female nematodes and gall tissues for tem observations. | microwave irradiation of glutaraldehyde-immersed samples was evaluated for the chemical fixation of 3-week-old galls that resulted from the infection of tomato roots (lycopersicon esculentum) by a root-knot nematode, meloidogyne incognita. observation by transmission electron microscopy indicated that the best results were obtained when vials containing the intact galls were immersed in buffered glutaraldehyde and irradiated for 10 seconds then allowed to cool for 30 seconds; this procedure was ... | 2000 | 19270984 |
| variability in time and space of meloidogyne incognita fall population density in cotton fields. | three cotton fields infested with meloidogyne incognita were intensively sampled in the fall for 3 years (1996 to 1998) to determine if intensive sampling for m. incognita, for which spatial location is important, was necessary every year in a continuous cotton system. two composite soil samples (20 cores each), taken over an area covering one-third of the field length and two rows wide, were averaged to represent that area (row-location combination). each field (except one) had 24 areas assayed ... | 2000 | 19270975 |
| nematicidal constituents of the aerial parts of lantana camara. | two new constituents, lantanoside (1) and lantanone (2), and the known compounds linaroside (3) and camarinic acid (4) were isolated from the aerial parts of lantana camara. compounds 1, 3, and 4 were tested for nematicidal activity against root-knot nematode meloidogyne incognita and showed 90, 85, and 100% mortality, respectively, at 1.0% concentration. the results were comparable to those obtained with the conventional nematicide furadan (100% mortality at 1.0% concentration). structures of t ... | 2000 | 10869197 |
| effect of mulch surface color on root-knot of tomato grown in simulated planting beds. | the effect of different-colored polyethylene mulches on quantity and spectra of reflected light, plant morphology, and root-knot disease was studied in tomato (lycopersicon esculentum) grown in simulated planting beds. tomato plants were inoculated with meloidogyne incognita at initial populations (pi) of 0, 1,000, 10,000, or 50,000 eggs/plant, and grown in a greenhouse for 50 days over white, red, or black mulch. soil temperature was kept constant among the mulch treatments by placing an insula ... | 2000 | 19270954 |
| comparison of variable and single-rate applications of aldicarb on cotton yield in fields infested with meloidogyne incognita. | variable-rate applications of the nematicide aldicarb were compared to producer standard rates in eight field tests over 3 years. test areas (308 to 1,015 m long) were divided into eight or five blocks. each block contained two plots with a variable-rate treatment (vrt) of aldicarb and a producer standard treatment (pst) of aldicarb. each vrt plot was divided into three subunits and intensively sampled for meloidogyne incognita in either the fall or spring before planting. rates of aldicarb were ... | 1999 | 19270939 |
| evaluation of dry ice as a potential cryonematicide for meloidogyne incognita in soil. | solid co (dry ice) was added to pots containing soil that was infested either with eggs of the root-knot nematode, meloidogyne incognita, or with tomato (lycopersicon esculentum 'rutgers') root fragments that were infected with various stages of the nematode. two hours after dry ice was added, thermocouples in the soil recorded temperatures ranging from -15 degrees c to -59 degrees c. one day after treatment with the dry ice, the temperature of the soil was allowed to equilibrate with that of th ... | 1999 | 19270918 |
| isolation of a cdna encoding a beta-1,4-endoglucanase in the root-knot nematode meloidogyne incognita and expression analysis during plant parasitism. | a beta-1,4-endoglucanase encoding cdna (egases, e.c. 3.2.1.4), named mi-eng-1, was cloned from meloidogyne incognita second-stage juveniles (j2). the deduced amino acid sequence contains a catalytic domain and a cellulose-binding domain separated by a linker. in m. incognita, the gene is transcribed in the migratory j2, in males, and in the sedentary adult females. in pre-parasitic j2, endoglucanase transcripts are located in the cytoplasm of the subventral esophageal glands. the presence of bet ... | 1999 | 10478479 |
| carbon partitioning in soybean infected with meloidogyne incognita and m. javanica. | seven-day-old seedlings of two cultivars (cristalina and ufv itm1) of glycine max were inoculated with 0, 3,000, 9,000, or 27,000 eggs of meloidogyne incognita race 3 or m. javanica and maintained in a greenhouse. thirty days later, plants were exposed to (1)co for 4 hours. twenty hours after (1)co exposure, the root fresh weight, leaf dry weight, nematode eggs per gram of root, total and specific radioactivity of carbohydrates in roots, and root carbohydrate content were evaluated. meloidogyne ... | 1999 | 19270907 |
| reproduction and development of meloidogyne incognita and m. javanica on guardian peach rootstock. | guardian peach rootstock was evaluated for susceptibility to meloidogyne incognita race 3 (georgia-peach isolate) and m. javanica in the greenhouse. both commercial guardian seed sources produced plants that were poor hosts of m. incognita and m. javanica. reproduction as measured by number of egg masses and eggs per plant, eggs per egg mass, and eggs per gram of root were a better measure of host resistance than number of root galls per plant. penetration, development, and reproduction of m. in ... | 1999 | 19270905 |
| effects of a resistant corn hybrid and fenamiphos on meloidogyne incognita in a corn-squash rotation. | the efficacy of a double-cross corn (zea mays) hybrid (old raccoon selection x t216) x (tebeau selection x mp 307) resistant to meloidogyne incognita as a rotational crop, and fenamiphos treatment for management of root-knot nematode (m. incognita race 1) in squash (cucurbita pepo var. melopepo) was evaluated in field tests during 1996 and 1997. numbers of m. incognita in the soil and root-gall indices were lower on the resistant hybrid than on a commercial cultivar dekalb dk-683. treatment mean ... | 1999 | 19270888 |
| rhizosphere colonization and control of meloidogyne spp. by nematode-trapping fungi. | the ability of nematode-trapping fungi to colonize the rhizosphere of crop plants has been suggested to be an important factor in biological control of root-infecting nematodes. in this study, rhizosphere colonization was evaluated for 38 isolates of nematode-trapping fungi representing 11 species. in an initial screen, arthrobotrys dactyloides, a. superba, and monacrosporium ellipsosporum were most frequently detected in the tomato rhizosphere. in subsequent pot experiments these fungi and the ... | 1999 | 19270886 |
| molecular cloning of an acetylcholinesterase gene from the plant parasitic nematodes, meloidogyne incognita and meloidogyne javanica. | a gene encoding a protein with strong homology with caenorhabditis elegans and c. briggsae acetylcholinesterase ace-1 was cloned from meloidogyne incognita and m. javanica pre-parasitic juveniles. both cdnas have an orf of 1968 bp for a deduced translation product of 656 amino acid residues. the key residues essential to acetylcholinesterase (ache) structure and function are conserved in both sequences. m. incognita and m. javanica ache share a homology of 98.8% at the amino acid level and 97% a ... | 1999 | 10340488 |
| the tomato mi-1 gene confers resistance to both root-knot nematodes and potato aphids. | mi-1, a lycopersicon peruvianum gene conferring resistance to the agricultural pests, root-knot nematodes, and introgressed into tomato, has been cloned using a selective restriction fragment amplification based strategy. complementation analysis of a susceptible tomato line with a 100 kb cosmid array yielded a single cosmid clone capable of conferring resistance both to the root-knot nematode meloidogyne incognita and to an unrelated pathogen, the potato aphid macrosiphum euphorbiae. this resis ... | 1998 | 9853621 |
| rpe, a plant gene involved in early developmental steps of nematode feeding cells. | sedentary plant-parasitic nematodes are able to induce the redifferentiation of root cells into multinucleate nematode feeding sites (nfss). we have isolated by promoter trapping an arabidopsis thaliana gene that is essential for the early steps of nfs formation induced by the root-knot nematode meloidogyne incognita. its pattern of expression is similar to that of key regulators of the cell cycle, but it is not observed with the cyst nematode. later in nfs development, this gene is induced by b ... | 1998 | 9843485 |
| reducing meloidogyne incognita injury to cucumber in a tomato-cucumber double-cropping system. | the effects of a root-knot nematode-resistant tomato cultivar and application of the nematicide ethoprop on root-knot nematode injury to cucumber were compared in a tomato-cucumber double-cropping system. a root-knot nematode-resistant tomato cultivar, celebrity, and a susceptible cultivar, heatwave, were grown in rotation with cucumber in 1995 and 1996. celebrity suppressed populations of meloidogyne incognita in the soil and resulted in a low root-gall rating on the subsequent cucumber crop. n ... | 1998 | 19274214 |
| potential of foliar, dip, and injection applications of avermectins for control of plant-parasitic nematodes. | studies were conducted to determine the potential of two avermectin compounds, abamectin and emamectin benzoate, for controlling plant-parasitic nematodes when applied by three methods: foliar spray, root dip, and pseudostem injection. experiments were conducted against meloidogyne incognita on tomato, m. javanica on banana, and radopholus similis on banana. foliar applications of both avermectins to banana and tomato were not effective for controlling any of the nematodes evaluated. root dips o ... | 1998 | 19274200 |
| degradation of fenamiphos in agricultural production soil. | nematicides are used to control a wide variety of nematodes on many crops; unfortunately, oftentimes the control they provide is erratic. this erratic behavior is not always predictable and has been associated with chemical, physical, and biological degradation of nematicides. their accelerated degradation is an agricultural problem that has been observed in crop monocultures and in other crop production systems where a biodegradable compound is repeatedly applied to the same soil. the problem c ... | 1998 | 19274197 |
| impact of meloidogyne incognita on the incidence of peach tree short life in the presence of criconemella xenoplax. | the relationship between cricenemella xenoplax alone and in combination with meloidogyne incognitaon the incidence of peach tree short life disease was studied in field microplots during 1989-96. the presence of m. incognita suppressed the population density of c. xenoplax on lovell peach. tree trunk diameter was significantly reduced in the presence of both nematode species prior to 1993. soil ph was lowest in the co-infection treatment as compared with the uninoculated control on three of the ... | 1997 | 19274276 |
| colored mulches affect yield of fresh-market tomato infected with meloidogyne incognita. | the effects of different-colored polyethylene mulches on the quantity and spectra of reflected light, earliness of fruit set, fruit yield and quality, and root-knot disease were studied in field-grown, staked tomato (lycopersicon esculentum). white mulch reflected more photosynthetic light and a lower far-red-to-red ratio than red mulch, whereas black mulch reflected less than 5 percent of any color. soil temperatures and fruit yields were recorded for tomato plants inoculated with meloidogyne i ... | 1997 | 19274191 |
| evaluation of nemx, a new cultivar of cotton with high resistance to meloidogyne incognita. | the level of resistance to root-knot nematode, meloidogyne incognita, in nemx, a new cultivar of the acala-type upland cotton, was evaluated in relation to four resistant breeding lines (n6072, n8577, n901, and n903) and four susceptible cultivars (maxxa, sj2, royale, and prema). in growth pouch tests, an average of only 4 nematode egg masses was produced on roots of nemx or the resistant lines, compared to a significantly higher average of 21 on the susceptible cultivars. in pot tests, the nema ... | 1997 | 19274190 |
| activity and differential induction of chitinase isozymes in soybean cultivars resistant or susceptible to root-knot nematodes. | host physiological events in relation to infestation by parasitic nematodes are not well documented. soybean plant responses to meloidogyne incognita infestation were compared to resistant (bryan) and susceptible (brim) cultivars at 0, 1, 3, 10, 20, and 34 days after infestation (dai). the resistant cultivar had higher chitinase activity than the susceptible cultivar at every sample time beginning at 3 dai. results from isoelectric focusing gel electrophoresis analyses indicated that three acidi ... | 1997 | 19274189 |
| meloidogyne incognita inoculum source affects host suitability and growth of yellow nutsedge and chile pepper. | meloidogyne incognita (mi) reproduction and host plant responses in chile pepper (capsicum annuum) and yellow nutsedge (cyperus esculentus = yns) to three sources of inoculum obtained by rearing a single mi population on chile, yns, and tomato were evaluated in two factorial greenhouse experiments. the interactive effects of mi inoculum source and crop-weed competition were determined. in the absence of yns competition, chile growth was reduced less by mi inoculum from chile than by inoculum fro ... | 1997 | 19274174 |
| mentha x piperita, mentha spicata and effects of their essential oils on meloidogyne in soil. | six peppermint (mentha x piperita) and six spearmint (m. spicata) pi accessions were inoculated with meloidogyne incognita race 3 and m. arenaria race 2, under greenhouse conditions. no galls formed on roots of any of the plants inoculated with 1,800 eggs/pot. fewer than two galls per root system formed on three pi accessions of peppermint inoculated with m. incognita at 5,400 eggs/pot. only one peppermint accession developed galls when inoculated with m. arenaria, whereas none of the spearmint ... | 1996 | 19277186 |
| early root response to meloidogyne incognita in resistant and susceptible alfalfa cultivars. | the early events of meloidogyne incognita behavior and associated host responses following root penetration were studied in resistant (cv. moapa 69) and susceptible (cv. lahontan) alfalfa. ten-day-old seedlings of alfalfa cultivars were inoculated with second-stage juveniles (j2) and harvested 12, 24, 48, and 72 hours and 7, 14, and 21 days later. both cultivars supported similar root penetration and initial j2 migration. by 72 hours after inoculation the majority of j2 were amassed inside the v ... | 1996 | 19277165 |
| differentiation of meloidogyne incognita and m. arenaria novel resistance phenotypes in lycopersicon peruvianum and derived bridge-lines. | lycopersicon peruvianum pi 270435 clone 2r2 and pi 126443 clone 1mh were crossed reciprocally with three l. esculentum-l. peruvianum bridge-lines. the incongruity barrier between the two plant species was overcome; f1 progeny were obtained from crosses between four parental combinations without embryo-rescue culture. hybridity was confirmed by leaf and flower morphology and by the production of nematode-resistant f1 progeny on homozygous susceptible parents. clones of the five f1 bridgeline hybr ... | 1996 | 24162431 |
| effect of simulated rainfall on efficacy and leaching of two formulations of fenamiphos. | recoverable fenamiphos in the soil and residue in squash following different simulated rainfall treatments after nematicide application were determined in a 2-year study. efficacy of fenamiphos also was evaluated. fenamiphos treatments (3 sc and 15 g) were broadcast (6.7 kg a.i./ha) over plots and incorporated into the top 15 cm of soil immediately before planting 'dixie hybrid' squash. simulated rainfall treatments of 0, 2.5, and 5.0 cm water were applied 1 day after fenamiphos application. soi ... | 1996 | 19277156 |
| comparison of two sympatric pasteuria populations isolated from a tropical vertisol soil. | an isolate of pasteuria (designated ppmj) recovered from the root-knot nematode meloidogyne javanica, was characterized using host preference, spore morphometrics, and serology, and compared with another sympatric pasteuria isolate (designated pphc) collected from the cyst nematode, heterodera cajani. ppmj spores were larger (x 1.5) than the pphc spores and had a mean diameter of 3.4 μm after fixation for electron microscopy. the central body of ppmj spores was about twice as big as the central ... | 1996 | 24415311 |
| repulsion of meloidogyne incognita by alginate pellets containing hyphae of monacrosporium cionopagum, m. ellipsosporum, or hirsutella rhossiliensis. | the responses of second-stage juveniles (j2) of meloidogyne incognita race 3 to calcium alginate pellets containing hyphae of the nematophagous fungi monacrosporiura cionopagum, m. ellipsosporum, and hirsutella rhossiliensis were examined using cylinders (38-mm-diam., 40 or 72 mm long) of sand (94% <250-mum particle size). sand was wetted with a synthetic soil solution (10% moisture, 0.06 bar water potential). a layer of 10 or 20 pellets was placed 4 or 20 mm from one end of the cylinder. after ... | 1996 | 19277129 |
| a molecular study of root-knot nematode-induced feeding sites. | in a compatible interaction, root-knot nematodes (meloidogyne) induce a sophisticated feeding site shortly after they have penetrated the plant root. the feeding site contains metabolically highly active giant cells. to gain insight into the molecular aspects that are typical for giant cells, a cdna library from tomato roots infected with meloidogyne incognita was differentially screened to find induced genes. among the genes identified, two extensin genes (lemmi8 and lemmi11) and a lea-like gen ... | 1996 | 8580972 |
| effects of irrigation, nitrogen, and a nematicide on pearl millet. | pearl millet is used mainly as a temporary forage crop in the southern united states. a new pearl millet hybrid has potential as a major grain crop in the united states. the effects of nematodes, irrigation, a nematicide, and nitrogen rates on a new pearl millet grain hybrid, hgm-100, and nematode population changes were determined in a 2-year study. root-knot nematodes (meloidogyne incognita race 1) entered the roots of pearl millet and caused minimal galling, but produced large numbers of eggs ... | 1995 | 19277324 |
| effects and carry-over benefits of nematicides in soil planted to a sweet corn-squash-vetch cropping system. | the effects of irrigation on the efficacy of nematicides on meloidogyne incognita race 1 population densities, yield of sweet corn, and the carry-over of nematicidal effect in the squash crop were determined in a sweet corn-squash-vetch cropping system for 3 years. fenamiphos 15g and aldicarb 15g were applied at 6.7 kg a.i./ha and incorporated 15 cm deep with a tractor-mounted rototiller. ethylene dibromide (edb) was injected at 18 kg a.i./ha on each side of the sweet corn rows (total 36 kg a.i. ... | 1995 | 19277323 |
| effect of simulated rainfall on leaching and efficacy of fenamiphos. | there is increasing concern in the united states about the pesticide movement in soil, groundwater contamination, and pesticide residue in food. the objective of this study was to determine the efficacy, degradation, and movement of fenamiphos (nemacur 15g) in the soil and residues in squash fruit as influenced by four simulated rainfall treatments (2.5 or 5.0 cm each applied 1 or 3 days after nematicide application) under field conditions. in 1990, concentrations of fenamiphos were greater in t ... | 1995 | 19277322 |
| influence of meloidogyne incognita on the water relations of cotton grown in microplots. | the effects of meloidogyne incognita on the growth and water relations of cotton were evaluated in a 2-year field study. microplots containing methyl bromide-fumigated fine sandy loam soil were infested with the nematode and planted to cotton (gossypium hirsutum l.). treatments included addition of nematodes alone, addition of nematodes plus the insecticide-nematicide aldicarb (1.7 kg/ha), and an untreated control. meloidogyne incognita population densities reached high levels in both treatments ... | 1995 | 19277313 |
| effect of ammonium ions on egg hatching and second-stage juveniles of meloidogyne incognita in axenic tomato root culture. | eggs, either dispersed or in masses, and second-stage juveniles (j2) of meloidogyne incognita were exposed to different concentrations of ammonium ions in a nutrient agar medium upon which excised tomato roots were growing. egg hatch and j2 penetration of the roots was slowed or inhibited at high (54 and 324 mg/liter) but not at low (1.5 and 9 mg/liter) concentrations of ammonium nitrate. the effect of ammonium on j2 appeared to be temporary and reversible. high potassium nitrate concentration ( ... | 1995 | 19277298 |
| root cortical cell spherical bodies associated with an induced resistance reaction in monoxenic cultures of meloidogyne incognita. | the root-knot nematode meloidogyne incognita was monoxenically cultured on excised roots of soybean cv. pickett and tomato cv. rutgers in agar media containing either 0 to 1,600 mug/ml ammonium nitrate or 0 to 100 mug/ml urea. observations with scanning and transmission electron microscopy indicated that an elevated concentration of ammonium nitrate or urea inhibited giant cell formation and suppressed nematode development in the infected soybean roots. in the tomato roots, concentrations of amm ... | 1995 | 19277295 |
| survey of meloidogyne spp. in tomato production fields of baix llobregat county, spain. | a survey was conducted to determine the frequency and abundance of meloidogyne spp. in tomato production sites located in baix llobregat county, barcelona, spain. forty-five sites were sampled before planting and at harvest from february to october, 1991. meloidogyne spp. occurred in 49% of the sites sampled. preplant population densities ranged from 10 to 220 (x = 110)juveniles/ 250 cm(3) soil, and final population densities ranged from 20 to 1,530 (x = 410)juveniles/250 cm(3) soil. final popul ... | 1994 | 19279955 |
| efficacy of fenamiphos formulations applied through irrigation for control of meloidogyne incognita on squash. | management ofmeloidogyne incognita by chemigation with fenamiphos was studied in an infested field planted to m. incognita-suscepfible yellow summer squash cv. dixie hybrid. fenamiphos (vl 73.1% a.i. manufacturing concentrate in propylene glycol) was mixed with unitol dsr-90 or used as fenamiphos 3 sc (spray concentrate). both formulations, applied with 63.5 kl irrigation water per hectare, decreased numbers of m. incognita second-stage juveniles in the soil and root-gall indices, and increased ... | 1994 | 19279950 |
| efficacy and compatibility for fenamiphos and eptc applied in irrigation water for nematode and weed control in snapbean production. | a nematicide (fenamiphos) and a herbicide (eptc) were injected into a sprinkler irrigation system separately and as tank mixtures and applied in 25.4 kl water/ha for nematode and weed control on snapbean. there were no differences (p = 0.05) between methods of injection of fenamiphos + eptc on efficacy or crop response. the root-gall indices of cultivars eagle and gv 50 were lower in fenamiphos-treated plots than those treated with eptc alone and untreated plots. the yield and crop value were gr ... | 1994 | 19279949 |
| influence of 1,3-dichloropropene, fenamiphos, and carbofuran on meloidogyne incognita populations and yield of chile peppers. | field trials were conducted during 1986, 1988, 1989, and 1991 to compare the effects of 1,3-dichloropropene, fenamiphos, and carbofuran on yield and quality of chile peppers (capsicum annuum) in soil infested with meloidogyne incognita. when compared with untreated plots, numbers of m. incognita juveniles recovered from soil 60 and(or) 90 days after chile pepper emergence were reduced (p = 0.05) following 1,3-d treatment every year except 1986. nematode numbers were also reduced (p = 0.05) by fe ... | 1994 | 19279948 |
| reaction of ten cultivars of watermelon (citrullus lanatus) to a puerto rican population of meloidogyne incognita. | ten cultivars of watermelon were evaluated for their response to a puerto rican population of meloidogyne incognita under greenhouse conditions in a 2-year study (1989 and 1990). ten-day-old seedlings were planted in steam-sterilized soil in 15-cm-d plastic pots. the nematode inoculum consisted of 10,000 eggs and (or) second-stage juveniles (j2)/plant. the cultivars were sugar baby, charleston gray, seedless, prince charles, charleston 76, jubilee, florida giant, royal charleston, royal sweet, a ... | 1994 | 19279940 |
| optimal levels of meloidogyne incognita inoculum for infection of tomato and peach in vitro. | penetration of second-stage juveniles (j2) of meloidogyne incognita into tomato root explants and in vitro propagated peach plantlet roots were compared. five inoculum levels were used: 25, 50, 75, 100, and 200 j2 for tomato; and 50, 100, 200, 500, and 1,000j2 for peach. the greatest root penetration into tomato was 30% at the 75 j2 level, but the maximum penetration into peach roots was only 8% at the 200 j2 level. the difference (p = 0.05) in penetration of m. incognita at all inoculum levels ... | 1994 | 19279926 |
| partial characterization of cytosolic superoxide dismutase activity in the interaction of meloidogyne incognita with two cultivars of glycine max. | the closely related soybean (glycine max) cultivars centennial and pickett 71 were confirmed to be resistant and susceptible, respectively, to the root-knot nematode meloidogryne incognita. increases in superoxide dismutase (sod) activity were detected in roots of both soybean cultivars 48 hours following inoculation. superoxide dismutase activity increased in roots of the susceptible cultivar overall, but declined after 96 hours in roots of the resistant cultivar. the isoelectric points of sod ... | 1994 | 19279911 |
| low-temperature scanning electron microscope observations of the meloidogyne incognita egg mass: the gelatinous matrix and embryo development. | the root-knot nematode meloidogyne incognita was cultured monoxenically on excised tomato roots. galls and egg masses were observed daily using a light microscope. two phases were distinguished in the gelatinous matrix of the egg mass: a translucent, amorphous material on the surface of the egg mass and a denser, layered phase in which nematode eggs were deposited. egg masses were also cryofixed, fractured, and observed as frozen, hydrated specimens on a cold stage in a scanning electron microsc ... | 1994 | 19279909 |
| reproduction of virulent isolates of meloidogyne incognita on susceptible and mi-resistant tomato. | the reproductive potential of natural and laboratory-selected meloidogyne incognita isolates virulent against the tomato mi resistance gene, all derived from a single egg-mass, were compared when the nematodes were inoculated on susceptible and resistant tomato. fewer second-stage juveniles (p = 0.01) of the two virulent populations selected under laboratory conditions matured to females on the resistant tomato compared to the susceptible cultivar. in contrast, no differences were found between ... | 1994 | 19279899 |
| dna sequence and expression analysis of root-knot nematode-elicited giant cell transcripts. | fifty-eight cdna clones isolated from a library of transcripts exhibiting up regulation in tomato root giant cells induced by infection with the parasitic nematode meloidogyne incognita were characterized. a survey of plant tissues identified 31 transcripts present in tissues other than root, including actively dividing and expanding tissues and mature leaf tissues. the identities of approximately 20% of the giant cell transcripts were inferred from dna sequence data; they include sequences enco ... | 2011 | 8012051 |
| colonization of greenhouse nematode cultures by nematophagous mites and fungi. | unproductive > 7-year-old greenhouse cultures of citrus nematode (tylenchulus semipenetrans) had a well-developed soil invertebrate fauna that included nematophagous mite species characteristic of florida citrus groves. nematophagous mite densities in box cultures were 285 +/- 42 mites/liter, 2.5 to 25 times higher than densities in citrus nematode-infested groves. vigorous root-knot nematode (meloidogyne incognita) cultures grown in steam-pasteurized soil had few nematophagous mites until more ... | 1993 | 19279841 |
| effects of 1,3-dicliloropropene for meloidogyne incognita management on cotton produced under furrow irrigation. | field trials were conducted during 1990 to evaluate the effects of preplant soil fumigation with 1,3-dichloropropene (1,3-d) on yield and fiber quality of furrow-irrigated cotton cultivars subjected to high population densities of meloidogyne incognita. we measured the responses of eight upland cotton cultivars with different levels of root-knot nematode resistance and compared the responses of upland and pima cottons. reductions in lint weight ranged from 10 to 52% among cultivars grown in soil ... | 1993 | 19279835 |
| spatial and temporal interactions of meloidogyne incognita and soybean. | the spatial and temporal dynamics of meloidogyne incognita, relative to soybean shoot and root growth in field microplots, were determined at 11 sampling dates during a growing season. the population dynamics of m. incognita on soybean were dependent on initial population (pi), soil moisture, and root spatial distribution. final egg and juvenile population densities were greatest in plots with higher pi. the population densities of juveniles and eggs were highest from mid- to late-season and wer ... | 1993 | 19279833 |
| dynamics of concomitant populations of meloidogyne incognita and criconemella xenoplax on peach. | the interaction between meloidogyne incognita and criconemella xenoplax on nematode reproduction and growth of lovell peach was studied in field microlots and the greenhouse. meloidogyne incognita suppressed reproduction of c. xenoplax in both field and greenhouse experiments. tree growth, as measured by trunk diameter, was reduced (p </= 0.05) in the presence of m. incognita as compared with c. xenoplax of the uninoculated control trees 26 months following inoculation. a similar response regard ... | 1993 | 19279823 |
| response of peach scion cultivars and rootstocks to meloidogyne incognitain vitro and in microplots. | the response of the peach scion cultivars, jerseyqueen, redhaven, compact redhaven, and rio oso gem and rootstocks 'lovely and 'nemaguard' to inoculation with meloidogyne incognita was compared in vitro and in microplots. one or more parameters monitored in vitro correlated with at least one parameter monitored in microplots, 4 years after tree planting (1989). a range of responses was observed from highlysusceptible in lovell to resistant in nemaguard. in vitro and microplot data suggest high a ... | 1993 | 19279797 |
| dynamics of the nuclear complement of giant cells induced by meloidogyne incognita. | the total numbers of nuclei in giant cells induced by meloidogyne incognita in pea, lettuce, tomato, and broad bean were determined. mature giant cells from pea had the most nuclei per giant cell with a mean of 59 +/- 23, lettuce had the fewest with 26 +/- 16, and tomato and broad bean were intermediate. the rate of increase in numbers of nuclei for all plant species was greatest during the first 7 days after inoculation. no mitotic activity was observed in giant cells associated with adult nema ... | 1993 | 19279788 |
| energetics of meloidogyne incognita on resistant and susceptible alyceclover genotypes. | to determine the energy cost of a population of meloidogyne incognita on the roots of alyceclover, nematode biomass was estimated and equations in the literature were used to calculate energy budgets. amounts of energy consumed, respired, or used in production of nematode biomass were calculated. results suggested that severe infestations of root-knot nematodes can remove significant quantities of energy from their hosts. over a 36-day period, a population of 2.6 females of m. incognita per root ... | 1993 | 19279766 |